📌 Vendored imported go modules

vendor/github.com/BurntSushi/toml/.gitignore

@@ -0,0 +1,5 @@
+TAGS
+tags
+.*.swp
+tomlcheck/tomlcheck
+toml.test

vendor/github.com/BurntSushi/toml/.travis.yml

@@ -0,0 +1,15 @@
+language: go
+go:
+  - 1.1
+  - 1.2
+  - 1.3
+  - 1.4
+  - 1.5
+  - 1.6
+  - tip
+install:
+  - go install ./...
+  - go get github.com/BurntSushi/toml-test
+script:
+  - export PATH="$PATH:$HOME/gopath/bin"
+  - make test

vendor/github.com/BurntSushi/toml/COMPATIBLE

@@ -0,0 +1,3 @@
+Compatible with TOML version
+[v0.4.0](https://github.com/toml-lang/toml/blob/v0.4.0/versions/en/toml-v0.4.0.md)
+

vendor/github.com/BurntSushi/toml/COPYING

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2013 TOML authors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/BurntSushi/toml/Makefile

@@ -0,0 +1,19 @@
+install:
+	go install ./...
+
+test: install
+	go test -v
+	toml-test toml-test-decoder
+	toml-test -encoder toml-test-encoder
+
+fmt:
+	gofmt -w *.go */*.go
+	colcheck *.go */*.go
+
+tags:
+	find ./ -name '*.go' -print0 | xargs -0 gotags > TAGS
+
+push:
+	git push origin master
+	git push github master
+

vendor/github.com/BurntSushi/toml/README.md

@@ -0,0 +1,218 @@
+## TOML parser and encoder for Go with reflection
+
+TOML stands for Tom's Obvious, Minimal Language. This Go package provides a
+reflection interface similar to Go's standard library `json` and `xml`
+packages. This package also supports the `encoding.TextUnmarshaler` and
+`encoding.TextMarshaler` interfaces so that you can define custom data
+representations. (There is an example of this below.)
+
+Spec: https://github.com/toml-lang/toml
+
+Compatible with TOML version
+[v0.4.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.4.0.md)
+
+Documentation: https://godoc.org/github.com/BurntSushi/toml
+
+Installation:
+
+```bash
+go get github.com/BurntSushi/toml
+```
+
+Try the toml validator:
+
+```bash
+go get github.com/BurntSushi/toml/cmd/tomlv
+tomlv some-toml-file.toml
+```
+
+[![Build Status](https://travis-ci.org/BurntSushi/toml.svg?branch=master)](https://travis-ci.org/BurntSushi/toml) [![GoDoc](https://godoc.org/github.com/BurntSushi/toml?status.svg)](https://godoc.org/github.com/BurntSushi/toml)
+
+### Testing
+
+This package passes all tests in
+[toml-test](https://github.com/BurntSushi/toml-test) for both the decoder
+and the encoder.
+
+### Examples
+
+This package works similarly to how the Go standard library handles `XML`
+and `JSON`. Namely, data is loaded into Go values via reflection.
+
+For the simplest example, consider some TOML file as just a list of keys
+and values:
+
+```toml
+Age = 25
+Cats = [ "Cauchy", "Plato" ]
+Pi = 3.14
+Perfection = [ 6, 28, 496, 8128 ]
+DOB = 1987-07-05T05:45:00Z
+```
+
+Which could be defined in Go as:
+
+```go
+type Config struct {
+  Age int
+  Cats []string
+  Pi float64
+  Perfection []int
+  DOB time.Time // requires `import time`
+}
+```
+
+And then decoded with:
+
+```go
+var conf Config
+if _, err := toml.Decode(tomlData, &conf); err != nil {
+  // handle error
+}
+```
+
+You can also use struct tags if your struct field name doesn't map to a TOML
+key value directly:
+
+```toml
+some_key_NAME = "wat"
+```
+
+```go
+type TOML struct {
+  ObscureKey string `toml:"some_key_NAME"`
+}
+```
+
+### Using the `encoding.TextUnmarshaler` interface
+
+Here's an example that automatically parses duration strings into
+`time.Duration` values:
+
+```toml
+[[song]]
+name = "Thunder Road"
+duration = "4m49s"
+
+[[song]]
+name = "Stairway to Heaven"
+duration = "8m03s"
+```
+
+Which can be decoded with:
+
+```go
+type song struct {
+  Name     string
+  Duration duration
+}
+type songs struct {
+  Song []song
+}
+var favorites songs
+if _, err := toml.Decode(blob, &favorites); err != nil {
+  log.Fatal(err)
+}
+
+for _, s := range favorites.Song {
+  fmt.Printf("%s (%s)\n", s.Name, s.Duration)
+}
+```
+
+And you'll also need a `duration` type that satisfies the
+`encoding.TextUnmarshaler` interface:
+
+```go
+type duration struct {
+	time.Duration
+}
+
+func (d *duration) UnmarshalText(text []byte) error {
+	var err error
+	d.Duration, err = time.ParseDuration(string(text))
+	return err
+}
+```
+
+### More complex usage
+
+Here's an example of how to load the example from the official spec page:
+
+```toml
+# This is a TOML document. Boom.
+
+title = "TOML Example"
+
+[owner]
+name = "Tom Preston-Werner"
+organization = "GitHub"
+bio = "GitHub Cofounder & CEO\nLikes tater tots and beer."
+dob = 1979-05-27T07:32:00Z # First class dates? Why not?
+
+[database]
+server = "192.168.1.1"
+ports = [ 8001, 8001, 8002 ]
+connection_max = 5000
+enabled = true
+
+[servers]
+
+  # You can indent as you please. Tabs or spaces. TOML don't care.
+  [servers.alpha]
+  ip = "10.0.0.1"
+  dc = "eqdc10"
+
+  [servers.beta]
+  ip = "10.0.0.2"
+  dc = "eqdc10"
+
+[clients]
+data = [ ["gamma", "delta"], [1, 2] ] # just an update to make sure parsers support it
+
+# Line breaks are OK when inside arrays
+hosts = [
+  "alpha",
+  "omega"
+]
+```
+
+And the corresponding Go types are:
+
+```go
+type tomlConfig struct {
+	Title string
+	Owner ownerInfo
+	DB database `toml:"database"`
+	Servers map[string]server
+	Clients clients
+}
+
+type ownerInfo struct {
+	Name string
+	Org string `toml:"organization"`
+	Bio string
+	DOB time.Time
+}
+
+type database struct {
+	Server string
+	Ports []int
+	ConnMax int `toml:"connection_max"`
+	Enabled bool
+}
+
+type server struct {
+	IP string
+	DC string
+}
+
+type clients struct {
+	Data [][]interface{}
+	Hosts []string
+}
+```
+
+Note that a case insensitive match will be tried if an exact match can't be
+found.
+
+A working example of the above can be found in `_examples/example.{go,toml}`.

vendor/github.com/BurntSushi/toml/decode.go

@@ -0,0 +1,509 @@
+package toml
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math"
+	"reflect"
+	"strings"
+	"time"
+)
+
+func e(format string, args ...interface{}) error {
+	return fmt.Errorf("toml: "+format, args...)
+}
+
+// Unmarshaler is the interface implemented by objects that can unmarshal a
+// TOML description of themselves.
+type Unmarshaler interface {
+	UnmarshalTOML(interface{}) error
+}
+
+// Unmarshal decodes the contents of `p` in TOML format into a pointer `v`.
+func Unmarshal(p []byte, v interface{}) error {
+	_, err := Decode(string(p), v)
+	return err
+}
+
+// Primitive is a TOML value that hasn't been decoded into a Go value.
+// When using the various `Decode*` functions, the type `Primitive` may
+// be given to any value, and its decoding will be delayed.
+//
+// A `Primitive` value can be decoded using the `PrimitiveDecode` function.
+//
+// The underlying representation of a `Primitive` value is subject to change.
+// Do not rely on it.
+//
+// N.B. Primitive values are still parsed, so using them will only avoid
+// the overhead of reflection. They can be useful when you don't know the
+// exact type of TOML data until run time.
+type Primitive struct {
+	undecoded interface{}
+	context   Key
+}
+
+// DEPRECATED!
+//
+// Use MetaData.PrimitiveDecode instead.
+func PrimitiveDecode(primValue Primitive, v interface{}) error {
+	md := MetaData{decoded: make(map[string]bool)}
+	return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// PrimitiveDecode is just like the other `Decode*` functions, except it
+// decodes a TOML value that has already been parsed. Valid primitive values
+// can *only* be obtained from values filled by the decoder functions,
+// including this method. (i.e., `v` may contain more `Primitive`
+// values.)
+//
+// Meta data for primitive values is included in the meta data returned by
+// the `Decode*` functions with one exception: keys returned by the Undecoded
+// method will only reflect keys that were decoded. Namely, any keys hidden
+// behind a Primitive will be considered undecoded. Executing this method will
+// update the undecoded keys in the meta data. (See the example.)
+func (md *MetaData) PrimitiveDecode(primValue Primitive, v interface{}) error {
+	md.context = primValue.context
+	defer func() { md.context = nil }()
+	return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// Decode will decode the contents of `data` in TOML format into a pointer
+// `v`.
+//
+// TOML hashes correspond to Go structs or maps. (Dealer's choice. They can be
+// used interchangeably.)
+//
+// TOML arrays of tables correspond to either a slice of structs or a slice
+// of maps.
+//
+// TOML datetimes correspond to Go `time.Time` values.
+//
+// All other TOML types (float, string, int, bool and array) correspond
+// to the obvious Go types.
+//
+// An exception to the above rules is if a type implements the
+// encoding.TextUnmarshaler interface. In this case, any primitive TOML value
+// (floats, strings, integers, booleans and datetimes) will be converted to
+// a byte string and given to the value's UnmarshalText method. See the
+// Unmarshaler example for a demonstration with time duration strings.
+//
+// Key mapping
+//
+// TOML keys can map to either keys in a Go map or field names in a Go
+// struct. The special `toml` struct tag may be used to map TOML keys to
+// struct fields that don't match the key name exactly. (See the example.)
+// A case insensitive match to struct names will be tried if an exact match
+// can't be found.
+//
+// The mapping between TOML values and Go values is loose. That is, there
+// may exist TOML values that cannot be placed into your representation, and
+// there may be parts of your representation that do not correspond to
+// TOML values. This loose mapping can be made stricter by using the IsDefined
+// and/or Undecoded methods on the MetaData returned.
+//
+// This decoder will not handle cyclic types. If a cyclic type is passed,
+// `Decode` will not terminate.
+func Decode(data string, v interface{}) (MetaData, error) {
+	rv := reflect.ValueOf(v)
+	if rv.Kind() != reflect.Ptr {
+		return MetaData{}, e("Decode of non-pointer %s", reflect.TypeOf(v))
+	}
+	if rv.IsNil() {
+		return MetaData{}, e("Decode of nil %s", reflect.TypeOf(v))
+	}
+	p, err := parse(data)
+	if err != nil {
+		return MetaData{}, err
+	}
+	md := MetaData{
+		p.mapping, p.types, p.ordered,
+		make(map[string]bool, len(p.ordered)), nil,
+	}
+	return md, md.unify(p.mapping, indirect(rv))
+}
+
+// DecodeFile is just like Decode, except it will automatically read the
+// contents of the file at `fpath` and decode it for you.
+func DecodeFile(fpath string, v interface{}) (MetaData, error) {
+	bs, err := ioutil.ReadFile(fpath)
+	if err != nil {
+		return MetaData{}, err
+	}
+	return Decode(string(bs), v)
+}
+
+// DecodeReader is just like Decode, except it will consume all bytes
+// from the reader and decode it for you.
+func DecodeReader(r io.Reader, v interface{}) (MetaData, error) {
+	bs, err := ioutil.ReadAll(r)
+	if err != nil {
+		return MetaData{}, err
+	}
+	return Decode(string(bs), v)
+}
+
+// unify performs a sort of type unification based on the structure of `rv`,
+// which is the client representation.
+//
+// Any type mismatch produces an error. Finding a type that we don't know
+// how to handle produces an unsupported type error.
+func (md *MetaData) unify(data interface{}, rv reflect.Value) error {
+
+	// Special case. Look for a `Primitive` value.
+	if rv.Type() == reflect.TypeOf((*Primitive)(nil)).Elem() {
+		// Save the undecoded data and the key context into the primitive
+		// value.
+		context := make(Key, len(md.context))
+		copy(context, md.context)
+		rv.Set(reflect.ValueOf(Primitive{
+			undecoded: data,
+			context:   context,
+		}))
+		return nil
+	}
+
+	// Special case. Unmarshaler Interface support.
+	if rv.CanAddr() {
+		if v, ok := rv.Addr().Interface().(Unmarshaler); ok {
+			return v.UnmarshalTOML(data)
+		}
+	}
+
+	// Special case. Handle time.Time values specifically.
+	// TODO: Remove this code when we decide to drop support for Go 1.1.
+	// This isn't necessary in Go 1.2 because time.Time satisfies the encoding
+	// interfaces.
+	if rv.Type().AssignableTo(rvalue(time.Time{}).Type()) {
+		return md.unifyDatetime(data, rv)
+	}
+
+	// Special case. Look for a value satisfying the TextUnmarshaler interface.
+	if v, ok := rv.Interface().(TextUnmarshaler); ok {
+		return md.unifyText(data, v)
+	}
+	// BUG(burntsushi)
+	// The behavior here is incorrect whenever a Go type satisfies the
+	// encoding.TextUnmarshaler interface but also corresponds to a TOML
+	// hash or array. In particular, the unmarshaler should only be applied
+	// to primitive TOML values. But at this point, it will be applied to
+	// all kinds of values and produce an incorrect error whenever those values
+	// are hashes or arrays (including arrays of tables).
+
+	k := rv.Kind()
+
+	// laziness
+	if k >= reflect.Int && k <= reflect.Uint64 {
+		return md.unifyInt(data, rv)
+	}
+	switch k {
+	case reflect.Ptr:
+		elem := reflect.New(rv.Type().Elem())
+		err := md.unify(data, reflect.Indirect(elem))
+		if err != nil {
+			return err
+		}
+		rv.Set(elem)
+		return nil
+	case reflect.Struct:
+		return md.unifyStruct(data, rv)
+	case reflect.Map:
+		return md.unifyMap(data, rv)
+	case reflect.Array:
+		return md.unifyArray(data, rv)
+	case reflect.Slice:
+		return md.unifySlice(data, rv)
+	case reflect.String:
+		return md.unifyString(data, rv)
+	case reflect.Bool:
+		return md.unifyBool(data, rv)
+	case reflect.Interface:
+		// we only support empty interfaces.
+		if rv.NumMethod() > 0 {
+			return e("unsupported type %s", rv.Type())
+		}
+		return md.unifyAnything(data, rv)
+	case reflect.Float32:
+		fallthrough
+	case reflect.Float64:
+		return md.unifyFloat64(data, rv)
+	}
+	return e("unsupported type %s", rv.Kind())
+}
+
+func (md *MetaData) unifyStruct(mapping interface{}, rv reflect.Value) error {
+	tmap, ok := mapping.(map[string]interface{})
+	if !ok {
+		if mapping == nil {
+			return nil
+		}
+		return e("type mismatch for %s: expected table but found %T",
+			rv.Type().String(), mapping)
+	}
+
+	for key, datum := range tmap {
+		var f *field
+		fields := cachedTypeFields(rv.Type())
+		for i := range fields {
+			ff := &fields[i]
+			if ff.name == key {
+				f = ff
+				break
+			}
+			if f == nil && strings.EqualFold(ff.name, key) {
+				f = ff
+			}
+		}
+		if f != nil {
+			subv := rv
+			for _, i := range f.index {
+				subv = indirect(subv.Field(i))
+			}
+			if isUnifiable(subv) {
+				md.decoded[md.context.add(key).String()] = true
+				md.context = append(md.context, key)
+				if err := md.unify(datum, subv); err != nil {
+					return err
+				}
+				md.context = md.context[0 : len(md.context)-1]
+			} else if f.name != "" {
+				// Bad user! No soup for you!
+				return e("cannot write unexported field %s.%s",
+					rv.Type().String(), f.name)
+			}
+		}
+	}
+	return nil
+}
+
+func (md *MetaData) unifyMap(mapping interface{}, rv reflect.Value) error {
+	tmap, ok := mapping.(map[string]interface{})
+	if !ok {
+		if tmap == nil {
+			return nil
+		}
+		return badtype("map", mapping)
+	}
+	if rv.IsNil() {
+		rv.Set(reflect.MakeMap(rv.Type()))
+	}
+	for k, v := range tmap {
+		md.decoded[md.context.add(k).String()] = true
+		md.context = append(md.context, k)
+
+		rvkey := indirect(reflect.New(rv.Type().Key()))
+		rvval := reflect.Indirect(reflect.New(rv.Type().Elem()))
+		if err := md.unify(v, rvval); err != nil {
+			return err
+		}
+		md.context = md.context[0 : len(md.context)-1]
+
+		rvkey.SetString(k)
+		rv.SetMapIndex(rvkey, rvval)
+	}
+	return nil
+}
+
+func (md *MetaData) unifyArray(data interface{}, rv reflect.Value) error {
+	datav := reflect.ValueOf(data)
+	if datav.Kind() != reflect.Slice {
+		if !datav.IsValid() {
+			return nil
+		}
+		return badtype("slice", data)
+	}
+	sliceLen := datav.Len()
+	if sliceLen != rv.Len() {
+		return e("expected array length %d; got TOML array of length %d",
+			rv.Len(), sliceLen)
+	}
+	return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySlice(data interface{}, rv reflect.Value) error {
+	datav := reflect.ValueOf(data)
+	if datav.Kind() != reflect.Slice {
+		if !datav.IsValid() {
+			return nil
+		}
+		return badtype("slice", data)
+	}
+	n := datav.Len()
+	if rv.IsNil() || rv.Cap() < n {
+		rv.Set(reflect.MakeSlice(rv.Type(), n, n))
+	}
+	rv.SetLen(n)
+	return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySliceArray(data, rv reflect.Value) error {
+	sliceLen := data.Len()
+	for i := 0; i < sliceLen; i++ {
+		v := data.Index(i).Interface()
+		sliceval := indirect(rv.Index(i))
+		if err := md.unify(v, sliceval); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (md *MetaData) unifyDatetime(data interface{}, rv reflect.Value) error {
+	if _, ok := data.(time.Time); ok {
+		rv.Set(reflect.ValueOf(data))
+		return nil
+	}
+	return badtype("time.Time", data)
+}
+
+func (md *MetaData) unifyString(data interface{}, rv reflect.Value) error {
+	if s, ok := data.(string); ok {
+		rv.SetString(s)
+		return nil
+	}
+	return badtype("string", data)
+}
+
+func (md *MetaData) unifyFloat64(data interface{}, rv reflect.Value) error {
+	if num, ok := data.(float64); ok {
+		switch rv.Kind() {
+		case reflect.Float32:
+			fallthrough
+		case reflect.Float64:
+			rv.SetFloat(num)
+		default:
+			panic("bug")
+		}
+		return nil
+	}
+	return badtype("float", data)
+}
+
+func (md *MetaData) unifyInt(data interface{}, rv reflect.Value) error {
+	if num, ok := data.(int64); ok {
+		if rv.Kind() >= reflect.Int && rv.Kind() <= reflect.Int64 {
+			switch rv.Kind() {
+			case reflect.Int, reflect.Int64:
+				// No bounds checking necessary.
+			case reflect.Int8:
+				if num < math.MinInt8 || num > math.MaxInt8 {
+					return e("value %d is out of range for int8", num)
+				}
+			case reflect.Int16:
+				if num < math.MinInt16 || num > math.MaxInt16 {
+					return e("value %d is out of range for int16", num)
+				}
+			case reflect.Int32:
+				if num < math.MinInt32 || num > math.MaxInt32 {
+					return e("value %d is out of range for int32", num)
+				}
+			}
+			rv.SetInt(num)
+		} else if rv.Kind() >= reflect.Uint && rv.Kind() <= reflect.Uint64 {
+			unum := uint64(num)
+			switch rv.Kind() {
+			case reflect.Uint, reflect.Uint64:
+				// No bounds checking necessary.
+			case reflect.Uint8:
+				if num < 0 || unum > math.MaxUint8 {
+					return e("value %d is out of range for uint8", num)
+				}
+			case reflect.Uint16:
+				if num < 0 || unum > math.MaxUint16 {
+					return e("value %d is out of range for uint16", num)
+				}
+			case reflect.Uint32:
+				if num < 0 || unum > math.MaxUint32 {
+					return e("value %d is out of range for uint32", num)
+				}
+			}
+			rv.SetUint(unum)
+		} else {
+			panic("unreachable")
+		}
+		return nil
+	}
+	return badtype("integer", data)
+}
+
+func (md *MetaData) unifyBool(data interface{}, rv reflect.Value) error {
+	if b, ok := data.(bool); ok {
+		rv.SetBool(b)
+		return nil
+	}
+	return badtype("boolean", data)
+}
+
+func (md *MetaData) unifyAnything(data interface{}, rv reflect.Value) error {
+	rv.Set(reflect.ValueOf(data))
+	return nil
+}
+
+func (md *MetaData) unifyText(data interface{}, v TextUnmarshaler) error {
+	var s string
+	switch sdata := data.(type) {
+	case TextMarshaler:
+		text, err := sdata.MarshalText()
+		if err != nil {
+			return err
+		}
+		s = string(text)
+	case fmt.Stringer:
+		s = sdata.String()
+	case string:
+		s = sdata
+	case bool:
+		s = fmt.Sprintf("%v", sdata)
+	case int64:
+		s = fmt.Sprintf("%d", sdata)
+	case float64:
+		s = fmt.Sprintf("%f", sdata)
+	default:
+		return badtype("primitive (string-like)", data)
+	}
+	if err := v.UnmarshalText([]byte(s)); err != nil {
+		return err
+	}
+	return nil
+}
+
+// rvalue returns a reflect.Value of `v`. All pointers are resolved.
+func rvalue(v interface{}) reflect.Value {
+	return indirect(reflect.ValueOf(v))
+}
+
+// indirect returns the value pointed to by a pointer.
+// Pointers are followed until the value is not a pointer.
+// New values are allocated for each nil pointer.
+//
+// An exception to this rule is if the value satisfies an interface of
+// interest to us (like encoding.TextUnmarshaler).
+func indirect(v reflect.Value) reflect.Value {
+	if v.Kind() != reflect.Ptr {
+		if v.CanSet() {
+			pv := v.Addr()
+			if _, ok := pv.Interface().(TextUnmarshaler); ok {
+				return pv
+			}
+		}
+		return v
+	}
+	if v.IsNil() {
+		v.Set(reflect.New(v.Type().Elem()))
+	}
+	return indirect(reflect.Indirect(v))
+}
+
+func isUnifiable(rv reflect.Value) bool {
+	if rv.CanSet() {
+		return true
+	}
+	if _, ok := rv.Interface().(TextUnmarshaler); ok {
+		return true
+	}
+	return false
+}
+
+func badtype(expected string, data interface{}) error {
+	return e("cannot load TOML value of type %T into a Go %s", data, expected)
+}

vendor/github.com/BurntSushi/toml/decode_meta.go

@@ -0,0 +1,121 @@
+package toml
+
+import "strings"
+
+// MetaData allows access to meta information about TOML data that may not
+// be inferrable via reflection. In particular, whether a key has been defined
+// and the TOML type of a key.
+type MetaData struct {
+	mapping map[string]interface{}
+	types   map[string]tomlType
+	keys    []Key
+	decoded map[string]bool
+	context Key // Used only during decoding.
+}
+
+// IsDefined returns true if the key given exists in the TOML data. The key
+// should be specified hierarchially. e.g.,
+//
+//	// access the TOML key 'a.b.c'
+//	IsDefined("a", "b", "c")
+//
+// IsDefined will return false if an empty key given. Keys are case sensitive.
+func (md *MetaData) IsDefined(key ...string) bool {
+	if len(key) == 0 {
+		return false
+	}
+
+	var hash map[string]interface{}
+	var ok bool
+	var hashOrVal interface{} = md.mapping
+	for _, k := range key {
+		if hash, ok = hashOrVal.(map[string]interface{}); !ok {
+			return false
+		}
+		if hashOrVal, ok = hash[k]; !ok {
+			return false
+		}
+	}
+	return true
+}
+
+// Type returns a string representation of the type of the key specified.
+//
+// Type will return the empty string if given an empty key or a key that
+// does not exist. Keys are case sensitive.
+func (md *MetaData) Type(key ...string) string {
+	fullkey := strings.Join(key, ".")
+	if typ, ok := md.types[fullkey]; ok {
+		return typ.typeString()
+	}
+	return ""
+}
+
+// Key is the type of any TOML key, including key groups. Use (MetaData).Keys
+// to get values of this type.
+type Key []string
+
+func (k Key) String() string {
+	return strings.Join(k, ".")
+}
+
+func (k Key) maybeQuotedAll() string {
+	var ss []string
+	for i := range k {
+		ss = append(ss, k.maybeQuoted(i))
+	}
+	return strings.Join(ss, ".")
+}
+
+func (k Key) maybeQuoted(i int) string {
+	quote := false
+	for _, c := range k[i] {
+		if !isBareKeyChar(c) {
+			quote = true
+			break
+		}
+	}
+	if quote {
+		return "\"" + strings.Replace(k[i], "\"", "\\\"", -1) + "\""
+	}
+	return k[i]
+}
+
+func (k Key) add(piece string) Key {
+	newKey := make(Key, len(k)+1)
+	copy(newKey, k)
+	newKey[len(k)] = piece
+	return newKey
+}
+
+// Keys returns a slice of every key in the TOML data, including key groups.
+// Each key is itself a slice, where the first element is the top of the
+// hierarchy and the last is the most specific.
+//
+// The list will have the same order as the keys appeared in the TOML data.
+//
+// All keys returned are non-empty.
+func (md *MetaData) Keys() []Key {
+	return md.keys
+}
+
+// Undecoded returns all keys that have not been decoded in the order in which
+// they appear in the original TOML document.
+//
+// This includes keys that haven't been decoded because of a Primitive value.
+// Once the Primitive value is decoded, the keys will be considered decoded.
+//
+// Also note that decoding into an empty interface will result in no decoding,
+// and so no keys will be considered decoded.
+//
+// In this sense, the Undecoded keys correspond to keys in the TOML document
+// that do not have a concrete type in your representation.
+func (md *MetaData) Undecoded() []Key {
+	undecoded := make([]Key, 0, len(md.keys))
+	for _, key := range md.keys {
+		if !md.decoded[key.String()] {
+			undecoded = append(undecoded, key)
+		}
+	}
+	return undecoded
+}

vendor/github.com/BurntSushi/toml/doc.go

@@ -0,0 +1,27 @@
+/*
+Package toml provides facilities for decoding and encoding TOML configuration
+files via reflection. There is also support for delaying decoding with
+the Primitive type, and querying the set of keys in a TOML document with the
+MetaData type.
+
+The specification implemented: https://github.com/toml-lang/toml
+
+The sub-command github.com/BurntSushi/toml/cmd/tomlv can be used to verify
+whether a file is a valid TOML document. It can also be used to print the
+type of each key in a TOML document.
+
+Testing
+
+There are two important types of tests used for this package. The first is
+contained inside '*_test.go' files and uses the standard Go unit testing
+framework. These tests are primarily devoted to holistically testing the
+decoder and encoder.
+
+The second type of testing is used to verify the implementation's adherence
+to the TOML specification. These tests have been factored into their own
+project: https://github.com/BurntSushi/toml-test
+
+The reason the tests are in a separate project is so that they can be used by
+any implementation of TOML. Namely, it is language agnostic.
+*/
+package toml

vendor/github.com/BurntSushi/toml/encode.go

@@ -0,0 +1,568 @@
+package toml
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type tomlEncodeError struct{ error }
+
+var (
+	errArrayMixedElementTypes = errors.New(
+		"toml: cannot encode array with mixed element types")
+	errArrayNilElement = errors.New(
+		"toml: cannot encode array with nil element")
+	errNonString = errors.New(
+		"toml: cannot encode a map with non-string key type")
+	errAnonNonStruct = errors.New(
+		"toml: cannot encode an anonymous field that is not a struct")
+	errArrayNoTable = errors.New(
+		"toml: TOML array element cannot contain a table")
+	errNoKey = errors.New(
+		"toml: top-level values must be Go maps or structs")
+	errAnything = errors.New("") // used in testing
+)
+
+var quotedReplacer = strings.NewReplacer(
+	"\t", "\\t",
+	"\n", "\\n",
+	"\r", "\\r",
+	"\"", "\\\"",
+	"\\", "\\\\",
+)
+
+// Encoder controls the encoding of Go values to a TOML document to some
+// io.Writer.
+//
+// The indentation level can be controlled with the Indent field.
+type Encoder struct {
+	// A single indentation level. By default it is two spaces.
+	Indent string
+
+	// hasWritten is whether we have written any output to w yet.
+	hasWritten bool
+	w          *bufio.Writer
+}
+
+// NewEncoder returns a TOML encoder that encodes Go values to the io.Writer
+// given. By default, a single indentation level is 2 spaces.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		w:      bufio.NewWriter(w),
+		Indent: "  ",
+	}
+}
+
+// Encode writes a TOML representation of the Go value to the underlying
+// io.Writer. If the value given cannot be encoded to a valid TOML document,
+// then an error is returned.
+//
+// The mapping between Go values and TOML values should be precisely the same
+// as for the Decode* functions. Similarly, the TextMarshaler interface is
+// supported by encoding the resulting bytes as strings. (If you want to write
+// arbitrary binary data then you will need to use something like base64 since
+// TOML does not have any binary types.)
+//
+// When encoding TOML hashes (i.e., Go maps or structs), keys without any
+// sub-hashes are encoded first.
+//
+// If a Go map is encoded, then its keys are sorted alphabetically for
+// deterministic output. More control over this behavior may be provided if
+// there is demand for it.
+//
+// Encoding Go values without a corresponding TOML representation---like map
+// types with non-string keys---will cause an error to be returned. Similarly
+// for mixed arrays/slices, arrays/slices with nil elements, embedded
+// non-struct types and nested slices containing maps or structs.
+// (e.g., [][]map[string]string is not allowed but []map[string]string is OK
+// and so is []map[string][]string.)
+func (enc *Encoder) Encode(v interface{}) error {
+	rv := eindirect(reflect.ValueOf(v))
+	if err := enc.safeEncode(Key([]string{}), rv); err != nil {
+		return err
+	}
+	return enc.w.Flush()
+}
+
+func (enc *Encoder) safeEncode(key Key, rv reflect.Value) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			if terr, ok := r.(tomlEncodeError); ok {
+				err = terr.error
+				return
+			}
+			panic(r)
+		}
+	}()
+	enc.encode(key, rv)
+	return nil
+}
+
+func (enc *Encoder) encode(key Key, rv reflect.Value) {
+	// Special case. Time needs to be in ISO8601 format.
+	// Special case. If we can marshal the type to text, then we used that.
+	// Basically, this prevents the encoder for handling these types as
+	// generic structs (or whatever the underlying type of a TextMarshaler is).
+	switch rv.Interface().(type) {
+	case time.Time, TextMarshaler:
+		enc.keyEqElement(key, rv)
+		return
+	}
+
+	k := rv.Kind()
+	switch k {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32,
+		reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32,
+		reflect.Uint64,
+		reflect.Float32, reflect.Float64, reflect.String, reflect.Bool:
+		enc.keyEqElement(key, rv)
+	case reflect.Array, reflect.Slice:
+		if typeEqual(tomlArrayHash, tomlTypeOfGo(rv)) {
+			enc.eArrayOfTables(key, rv)
+		} else {
+			enc.keyEqElement(key, rv)
+		}
+	case reflect.Interface:
+		if rv.IsNil() {
+			return
+		}
+		enc.encode(key, rv.Elem())
+	case reflect.Map:
+		if rv.IsNil() {
+			return
+		}
+		enc.eTable(key, rv)
+	case reflect.Ptr:
+		if rv.IsNil() {
+			return
+		}
+		enc.encode(key, rv.Elem())
+	case reflect.Struct:
+		enc.eTable(key, rv)
+	default:
+		panic(e("unsupported type for key '%s': %s", key, k))
+	}
+}
+
+// eElement encodes any value that can be an array element (primitives and
+// arrays).
+func (enc *Encoder) eElement(rv reflect.Value) {
+	switch v := rv.Interface().(type) {
+	case time.Time:
+		// Special case time.Time as a primitive. Has to come before
+		// TextMarshaler below because time.Time implements
+		// encoding.TextMarshaler, but we need to always use UTC.
+		enc.wf(v.UTC().Format("2006-01-02T15:04:05Z"))
+		return
+	case TextMarshaler:
+		// Special case. Use text marshaler if it's available for this value.
+		if s, err := v.MarshalText(); err != nil {
+			encPanic(err)
+		} else {
+			enc.writeQuoted(string(s))
+		}
+		return
+	}
+	switch rv.Kind() {
+	case reflect.Bool:
+		enc.wf(strconv.FormatBool(rv.Bool()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32,
+		reflect.Int64:
+		enc.wf(strconv.FormatInt(rv.Int(), 10))
+	case reflect.Uint, reflect.Uint8, reflect.Uint16,
+		reflect.Uint32, reflect.Uint64:
+		enc.wf(strconv.FormatUint(rv.Uint(), 10))
+	case reflect.Float32:
+		enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 32)))
+	case reflect.Float64:
+		enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 64)))
+	case reflect.Array, reflect.Slice:
+		enc.eArrayOrSliceElement(rv)
+	case reflect.Interface:
+		enc.eElement(rv.Elem())
+	case reflect.String:
+		enc.writeQuoted(rv.String())
+	default:
+		panic(e("unexpected primitive type: %s", rv.Kind()))
+	}
+}
+
+// By the TOML spec, all floats must have a decimal with at least one
+// number on either side.
+func floatAddDecimal(fstr string) string {
+	if !strings.Contains(fstr, ".") {
+		return fstr + ".0"
+	}
+	return fstr
+}
+
+func (enc *Encoder) writeQuoted(s string) {
+	enc.wf("\"%s\"", quotedReplacer.Replace(s))
+}
+
+func (enc *Encoder) eArrayOrSliceElement(rv reflect.Value) {
+	length := rv.Len()
+	enc.wf("[")
+	for i := 0; i < length; i++ {
+		elem := rv.Index(i)
+		enc.eElement(elem)
+		if i != length-1 {
+			enc.wf(", ")
+		}
+	}
+	enc.wf("]")
+}
+
+func (enc *Encoder) eArrayOfTables(key Key, rv reflect.Value) {
+	if len(key) == 0 {
+		encPanic(errNoKey)
+	}
+	for i := 0; i < rv.Len(); i++ {
+		trv := rv.Index(i)
+		if isNil(trv) {
+			continue
+		}
+		panicIfInvalidKey(key)
+		enc.newline()
+		enc.wf("%s[[%s]]", enc.indentStr(key), key.maybeQuotedAll())
+		enc.newline()
+		enc.eMapOrStruct(key, trv)
+	}
+}
+
+func (enc *Encoder) eTable(key Key, rv reflect.Value) {
+	panicIfInvalidKey(key)
+	if len(key) == 1 {
+		// Output an extra newline between top-level tables.
+		// (The newline isn't written if nothing else has been written though.)
+		enc.newline()
+	}
+	if len(key) > 0 {
+		enc.wf("%s[%s]", enc.indentStr(key), key.maybeQuotedAll())
+		enc.newline()
+	}
+	enc.eMapOrStruct(key, rv)
+}
+
+func (enc *Encoder) eMapOrStruct(key Key, rv reflect.Value) {
+	switch rv := eindirect(rv); rv.Kind() {
+	case reflect.Map:
+		enc.eMap(key, rv)
+	case reflect.Struct:
+		enc.eStruct(key, rv)
+	default:
+		panic("eTable: unhandled reflect.Value Kind: " + rv.Kind().String())
+	}
+}
+
+func (enc *Encoder) eMap(key Key, rv reflect.Value) {
+	rt := rv.Type()
+	if rt.Key().Kind() != reflect.String {
+		encPanic(errNonString)
+	}
+
+	// Sort keys so that we have deterministic output. And write keys directly
+	// underneath this key first, before writing sub-structs or sub-maps.
+	var mapKeysDirect, mapKeysSub []string
+	for _, mapKey := range rv.MapKeys() {
+		k := mapKey.String()
+		if typeIsHash(tomlTypeOfGo(rv.MapIndex(mapKey))) {
+			mapKeysSub = append(mapKeysSub, k)
+		} else {
+			mapKeysDirect = append(mapKeysDirect, k)
+		}
+	}
+
+	var writeMapKeys = func(mapKeys []string) {
+		sort.Strings(mapKeys)
+		for _, mapKey := range mapKeys {
+			mrv := rv.MapIndex(reflect.ValueOf(mapKey))
+			if isNil(mrv) {
+				// Don't write anything for nil fields.
+				continue
+			}
+			enc.encode(key.add(mapKey), mrv)
+		}
+	}
+	writeMapKeys(mapKeysDirect)
+	writeMapKeys(mapKeysSub)
+}
+
+func (enc *Encoder) eStruct(key Key, rv reflect.Value) {
+	// Write keys for fields directly under this key first, because if we write
+	// a field that creates a new table, then all keys under it will be in that
+	// table (not the one we're writing here).
+	rt := rv.Type()
+	var fieldsDirect, fieldsSub [][]int
+	var addFields func(rt reflect.Type, rv reflect.Value, start []int)
+	addFields = func(rt reflect.Type, rv reflect.Value, start []int) {
+		for i := 0; i < rt.NumField(); i++ {
+			f := rt.Field(i)
+			// skip unexported fields
+			if f.PkgPath != "" && !f.Anonymous {
+				continue
+			}
+			frv := rv.Field(i)
+			if f.Anonymous {
+				t := f.Type
+				switch t.Kind() {
+				case reflect.Struct:
+					// Treat anonymous struct fields with
+					// tag names as though they are not
+					// anonymous, like encoding/json does.
+					if getOptions(f.Tag).name == "" {
+						addFields(t, frv, f.Index)
+						continue
+					}
+				case reflect.Ptr:
+					if t.Elem().Kind() == reflect.Struct &&
+						getOptions(f.Tag).name == "" {
+						if !frv.IsNil() {
+							addFields(t.Elem(), frv.Elem(), f.Index)
+						}
+						continue
+					}
+					// Fall through to the normal field encoding logic below
+					// for non-struct anonymous fields.
+				}
+			}
+
+			if typeIsHash(tomlTypeOfGo(frv)) {
+				fieldsSub = append(fieldsSub, append(start, f.Index...))
+			} else {
+				fieldsDirect = append(fieldsDirect, append(start, f.Index...))
+			}
+		}
+	}
+	addFields(rt, rv, nil)
+
+	var writeFields = func(fields [][]int) {
+		for _, fieldIndex := range fields {
+			sft := rt.FieldByIndex(fieldIndex)
+			sf := rv.FieldByIndex(fieldIndex)
+			if isNil(sf) {
+				// Don't write anything for nil fields.
+				continue
+			}
+
+			opts := getOptions(sft.Tag)
+			if opts.skip {
+				continue
+			}
+			keyName := sft.Name
+			if opts.name != "" {
+				keyName = opts.name
+			}
+			if opts.omitempty && isEmpty(sf) {
+				continue
+			}
+			if opts.omitzero && isZero(sf) {
+				continue
+			}
+
+			enc.encode(key.add(keyName), sf)
+		}
+	}
+	writeFields(fieldsDirect)
+	writeFields(fieldsSub)
+}
+
+// tomlTypeName returns the TOML type name of the Go value's type. It is
+// used to determine whether the types of array elements are mixed (which is
+// forbidden). If the Go value is nil, then it is illegal for it to be an array
+// element, and valueIsNil is returned as true.
+
+// Returns the TOML type of a Go value. The type may be `nil`, which means
+// no concrete TOML type could be found.
+func tomlTypeOfGo(rv reflect.Value) tomlType {
+	if isNil(rv) || !rv.IsValid() {
+		return nil
+	}
+	switch rv.Kind() {
+	case reflect.Bool:
+		return tomlBool
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32,
+		reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32,
+		reflect.Uint64:
+		return tomlInteger
+	case reflect.Float32, reflect.Float64:
+		return tomlFloat
+	case reflect.Array, reflect.Slice:
+		if typeEqual(tomlHash, tomlArrayType(rv)) {
+			return tomlArrayHash
+		}
+		return tomlArray
+	case reflect.Ptr, reflect.Interface:
+		return tomlTypeOfGo(rv.Elem())
+	case reflect.String:
+		return tomlString
+	case reflect.Map:
+		return tomlHash
+	case reflect.Struct:
+		switch rv.Interface().(type) {
+		case time.Time:
+			return tomlDatetime
+		case TextMarshaler:
+			return tomlString
+		default:
+			return tomlHash
+		}
+	default:
+		panic("unexpected reflect.Kind: " + rv.Kind().String())
+	}
+}
+
+// tomlArrayType returns the element type of a TOML array. The type returned
+// may be nil if it cannot be determined (e.g., a nil slice or a zero length
+// slize). This function may also panic if it finds a type that cannot be
+// expressed in TOML (such as nil elements, heterogeneous arrays or directly
+// nested arrays of tables).
+func tomlArrayType(rv reflect.Value) tomlType {
+	if isNil(rv) || !rv.IsValid() || rv.Len() == 0 {
+		return nil
+	}
+	firstType := tomlTypeOfGo(rv.Index(0))
+	if firstType == nil {
+		encPanic(errArrayNilElement)
+	}
+
+	rvlen := rv.Len()
+	for i := 1; i < rvlen; i++ {
+		elem := rv.Index(i)
+		switch elemType := tomlTypeOfGo(elem); {
+		case elemType == nil:
+			encPanic(errArrayNilElement)
+		case !typeEqual(firstType, elemType):
+			encPanic(errArrayMixedElementTypes)
+		}
+	}
+	// If we have a nested array, then we must make sure that the nested
+	// array contains ONLY primitives.
+	// This checks arbitrarily nested arrays.
+	if typeEqual(firstType, tomlArray) || typeEqual(firstType, tomlArrayHash) {
+		nest := tomlArrayType(eindirect(rv.Index(0)))
+		if typeEqual(nest, tomlHash) || typeEqual(nest, tomlArrayHash) {
+			encPanic(errArrayNoTable)
+		}
+	}
+	return firstType
+}
+
+type tagOptions struct {
+	skip      bool // "-"
+	name      string
+	omitempty bool
+	omitzero  bool
+}
+
+func getOptions(tag reflect.StructTag) tagOptions {
+	t := tag.Get("toml")
+	if t == "-" {
+		return tagOptions{skip: true}
+	}
+	var opts tagOptions
+	parts := strings.Split(t, ",")
+	opts.name = parts[0]
+	for _, s := range parts[1:] {
+		switch s {
+		case "omitempty":
+			opts.omitempty = true
+		case "omitzero":
+			opts.omitzero = true
+		}
+	}
+	return opts
+}
+
+func isZero(rv reflect.Value) bool {
+	switch rv.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return rv.Int() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return rv.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return rv.Float() == 0.0
+	}
+	return false
+}
+
+func isEmpty(rv reflect.Value) bool {
+	switch rv.Kind() {
+	case reflect.Array, reflect.Slice, reflect.Map, reflect.String:
+		return rv.Len() == 0
+	case reflect.Bool:
+		return !rv.Bool()
+	}
+	return false
+}
+
+func (enc *Encoder) newline() {
+	if enc.hasWritten {
+		enc.wf("\n")
+	}
+}
+
+func (enc *Encoder) keyEqElement(key Key, val reflect.Value) {
+	if len(key) == 0 {
+		encPanic(errNoKey)
+	}
+	panicIfInvalidKey(key)
+	enc.wf("%s%s = ", enc.indentStr(key), key.maybeQuoted(len(key)-1))
+	enc.eElement(val)
+	enc.newline()
+}
+
+func (enc *Encoder) wf(format string, v ...interface{}) {
+	if _, err := fmt.Fprintf(enc.w, format, v...); err != nil {
+		encPanic(err)
+	}
+	enc.hasWritten = true
+}
+
+func (enc *Encoder) indentStr(key Key) string {
+	return strings.Repeat(enc.Indent, len(key)-1)
+}
+
+func encPanic(err error) {
+	panic(tomlEncodeError{err})
+}
+
+func eindirect(v reflect.Value) reflect.Value {
+	switch v.Kind() {
+	case reflect.Ptr, reflect.Interface:
+		return eindirect(v.Elem())
+	default:
+		return v
+	}
+}
+
+func isNil(rv reflect.Value) bool {
+	switch rv.Kind() {
+	case reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return rv.IsNil()
+	default:
+		return false
+	}
+}
+
+func panicIfInvalidKey(key Key) {
+	for _, k := range key {
+		if len(k) == 0 {
+			encPanic(e("Key '%s' is not a valid table name. Key names "+
+				"cannot be empty.", key.maybeQuotedAll()))
+		}
+	}
+}
+
+func isValidKeyName(s string) bool {
+	return len(s) != 0
+}

vendor/github.com/BurntSushi/toml/encoding_types.go

@@ -0,0 +1,19 @@
+// +build go1.2
+
+package toml
+
+// In order to support Go 1.1, we define our own TextMarshaler and
+// TextUnmarshaler types. For Go 1.2+, we just alias them with the
+// standard library interfaces.
+
+import (
+	"encoding"
+)
+
+// TextMarshaler is a synonym for encoding.TextMarshaler. It is defined here
+// so that Go 1.1 can be supported.
+type TextMarshaler encoding.TextMarshaler
+
+// TextUnmarshaler is a synonym for encoding.TextUnmarshaler. It is defined
+// here so that Go 1.1 can be supported.
+type TextUnmarshaler encoding.TextUnmarshaler

vendor/github.com/BurntSushi/toml/encoding_types_1.1.go

@@ -0,0 +1,18 @@
+// +build !go1.2
+
+package toml
+
+// These interfaces were introduced in Go 1.2, so we add them manually when
+// compiling for Go 1.1.
+
+// TextMarshaler is a synonym for encoding.TextMarshaler. It is defined here
+// so that Go 1.1 can be supported.
+type TextMarshaler interface {
+	MarshalText() (text []byte, err error)
+}
+
+// TextUnmarshaler is a synonym for encoding.TextUnmarshaler. It is defined
+// here so that Go 1.1 can be supported.
+type TextUnmarshaler interface {
+	UnmarshalText(text []byte) error
+}

vendor/github.com/BurntSushi/toml/lex.go

@@ -0,0 +1,953 @@
+package toml
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+type itemType int
+
+const (
+	itemError itemType = iota
+	itemNIL            // used in the parser to indicate no type
+	itemEOF
+	itemText
+	itemString
+	itemRawString
+	itemMultilineString
+	itemRawMultilineString
+	itemBool
+	itemInteger
+	itemFloat
+	itemDatetime
+	itemArray // the start of an array
+	itemArrayEnd
+	itemTableStart
+	itemTableEnd
+	itemArrayTableStart
+	itemArrayTableEnd
+	itemKeyStart
+	itemCommentStart
+	itemInlineTableStart
+	itemInlineTableEnd
+)
+
+const (
+	eof              = 0
+	comma            = ','
+	tableStart       = '['
+	tableEnd         = ']'
+	arrayTableStart  = '['
+	arrayTableEnd    = ']'
+	tableSep         = '.'
+	keySep           = '='
+	arrayStart       = '['
+	arrayEnd         = ']'
+	commentStart     = '#'
+	stringStart      = '"'
+	stringEnd        = '"'
+	rawStringStart   = '\''
+	rawStringEnd     = '\''
+	inlineTableStart = '{'
+	inlineTableEnd   = '}'
+)
+
+type stateFn func(lx *lexer) stateFn
+
+type lexer struct {
+	input string
+	start int
+	pos   int
+	line  int
+	state stateFn
+	items chan item
+
+	// Allow for backing up up to three runes.
+	// This is necessary because TOML contains 3-rune tokens (""" and ''').
+	prevWidths [3]int
+	nprev      int // how many of prevWidths are in use
+	// If we emit an eof, we can still back up, but it is not OK to call
+	// next again.
+	atEOF bool
+
+	// A stack of state functions used to maintain context.
+	// The idea is to reuse parts of the state machine in various places.
+	// For example, values can appear at the top level or within arbitrarily
+	// nested arrays. The last state on the stack is used after a value has
+	// been lexed. Similarly for comments.
+	stack []stateFn
+}
+
+type item struct {
+	typ  itemType
+	val  string
+	line int
+}
+
+func (lx *lexer) nextItem() item {
+	for {
+		select {
+		case item := <-lx.items:
+			return item
+		default:
+			lx.state = lx.state(lx)
+		}
+	}
+}
+
+func lex(input string) *lexer {
+	lx := &lexer{
+		input: input,
+		state: lexTop,
+		line:  1,
+		items: make(chan item, 10),
+		stack: make([]stateFn, 0, 10),
+	}
+	return lx
+}
+
+func (lx *lexer) push(state stateFn) {
+	lx.stack = append(lx.stack, state)
+}
+
+func (lx *lexer) pop() stateFn {
+	if len(lx.stack) == 0 {
+		return lx.errorf("BUG in lexer: no states to pop")
+	}
+	last := lx.stack[len(lx.stack)-1]
+	lx.stack = lx.stack[0 : len(lx.stack)-1]
+	return last
+}
+
+func (lx *lexer) current() string {
+	return lx.input[lx.start:lx.pos]
+}
+
+func (lx *lexer) emit(typ itemType) {
+	lx.items <- item{typ, lx.current(), lx.line}
+	lx.start = lx.pos
+}
+
+func (lx *lexer) emitTrim(typ itemType) {
+	lx.items <- item{typ, strings.TrimSpace(lx.current()), lx.line}
+	lx.start = lx.pos
+}
+
+func (lx *lexer) next() (r rune) {
+	if lx.atEOF {
+		panic("next called after EOF")
+	}
+	if lx.pos >= len(lx.input) {
+		lx.atEOF = true
+		return eof
+	}
+
+	if lx.input[lx.pos] == '\n' {
+		lx.line++
+	}
+	lx.prevWidths[2] = lx.prevWidths[1]
+	lx.prevWidths[1] = lx.prevWidths[0]
+	if lx.nprev < 3 {
+		lx.nprev++
+	}
+	r, w := utf8.DecodeRuneInString(lx.input[lx.pos:])
+	lx.prevWidths[0] = w
+	lx.pos += w
+	return r
+}
+
+// ignore skips over the pending input before this point.
+func (lx *lexer) ignore() {
+	lx.start = lx.pos
+}
+
+// backup steps back one rune. Can be called only twice between calls to next.
+func (lx *lexer) backup() {
+	if lx.atEOF {
+		lx.atEOF = false
+		return
+	}
+	if lx.nprev < 1 {
+		panic("backed up too far")
+	}
+	w := lx.prevWidths[0]
+	lx.prevWidths[0] = lx.prevWidths[1]
+	lx.prevWidths[1] = lx.prevWidths[2]
+	lx.nprev--
+	lx.pos -= w
+	if lx.pos < len(lx.input) && lx.input[lx.pos] == '\n' {
+		lx.line--
+	}
+}
+
+// accept consumes the next rune if it's equal to `valid`.
+func (lx *lexer) accept(valid rune) bool {
+	if lx.next() == valid {
+		return true
+	}
+	lx.backup()
+	return false
+}
+
+// peek returns but does not consume the next rune in the input.
+func (lx *lexer) peek() rune {
+	r := lx.next()
+	lx.backup()
+	return r
+}
+
+// skip ignores all input that matches the given predicate.
+func (lx *lexer) skip(pred func(rune) bool) {
+	for {
+		r := lx.next()
+		if pred(r) {
+			continue
+		}
+		lx.backup()
+		lx.ignore()
+		return
+	}
+}
+
+// errorf stops all lexing by emitting an error and returning `nil`.
+// Note that any value that is a character is escaped if it's a special
+// character (newlines, tabs, etc.).
+func (lx *lexer) errorf(format string, values ...interface{}) stateFn {
+	lx.items <- item{
+		itemError,
+		fmt.Sprintf(format, values...),
+		lx.line,
+	}
+	return nil
+}
+
+// lexTop consumes elements at the top level of TOML data.
+func lexTop(lx *lexer) stateFn {
+	r := lx.next()
+	if isWhitespace(r) || isNL(r) {
+		return lexSkip(lx, lexTop)
+	}
+	switch r {
+	case commentStart:
+		lx.push(lexTop)
+		return lexCommentStart
+	case tableStart:
+		return lexTableStart
+	case eof:
+		if lx.pos > lx.start {
+			return lx.errorf("unexpected EOF")
+		}
+		lx.emit(itemEOF)
+		return nil
+	}
+
+	// At this point, the only valid item can be a key, so we back up
+	// and let the key lexer do the rest.
+	lx.backup()
+	lx.push(lexTopEnd)
+	return lexKeyStart
+}
+
+// lexTopEnd is entered whenever a top-level item has been consumed. (A value
+// or a table.) It must see only whitespace, and will turn back to lexTop
+// upon a newline. If it sees EOF, it will quit the lexer successfully.
+func lexTopEnd(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case r == commentStart:
+		// a comment will read to a newline for us.
+		lx.push(lexTop)
+		return lexCommentStart
+	case isWhitespace(r):
+		return lexTopEnd
+	case isNL(r):
+		lx.ignore()
+		return lexTop
+	case r == eof:
+		lx.emit(itemEOF)
+		return nil
+	}
+	return lx.errorf("expected a top-level item to end with a newline, "+
+		"comment, or EOF, but got %q instead", r)
+}
+
+// lexTable lexes the beginning of a table. Namely, it makes sure that
+// it starts with a character other than '.' and ']'.
+// It assumes that '[' has already been consumed.
+// It also handles the case that this is an item in an array of tables.
+// e.g., '[[name]]'.
+func lexTableStart(lx *lexer) stateFn {
+	if lx.peek() == arrayTableStart {
+		lx.next()
+		lx.emit(itemArrayTableStart)
+		lx.push(lexArrayTableEnd)
+	} else {
+		lx.emit(itemTableStart)
+		lx.push(lexTableEnd)
+	}
+	return lexTableNameStart
+}
+
+func lexTableEnd(lx *lexer) stateFn {
+	lx.emit(itemTableEnd)
+	return lexTopEnd
+}
+
+func lexArrayTableEnd(lx *lexer) stateFn {
+	if r := lx.next(); r != arrayTableEnd {
+		return lx.errorf("expected end of table array name delimiter %q, "+
+			"but got %q instead", arrayTableEnd, r)
+	}
+	lx.emit(itemArrayTableEnd)
+	return lexTopEnd
+}
+
+func lexTableNameStart(lx *lexer) stateFn {
+	lx.skip(isWhitespace)
+	switch r := lx.peek(); {
+	case r == tableEnd || r == eof:
+		return lx.errorf("unexpected end of table name " +
+			"(table names cannot be empty)")
+	case r == tableSep:
+		return lx.errorf("unexpected table separator " +
+			"(table names cannot be empty)")
+	case r == stringStart || r == rawStringStart:
+		lx.ignore()
+		lx.push(lexTableNameEnd)
+		return lexValue // reuse string lexing
+	default:
+		return lexBareTableName
+	}
+}
+
+// lexBareTableName lexes the name of a table. It assumes that at least one
+// valid character for the table has already been read.
+func lexBareTableName(lx *lexer) stateFn {
+	r := lx.next()
+	if isBareKeyChar(r) {
+		return lexBareTableName
+	}
+	lx.backup()
+	lx.emit(itemText)
+	return lexTableNameEnd
+}
+
+// lexTableNameEnd reads the end of a piece of a table name, optionally
+// consuming whitespace.
+func lexTableNameEnd(lx *lexer) stateFn {
+	lx.skip(isWhitespace)
+	switch r := lx.next(); {
+	case isWhitespace(r):
+		return lexTableNameEnd
+	case r == tableSep:
+		lx.ignore()
+		return lexTableNameStart
+	case r == tableEnd:
+		return lx.pop()
+	default:
+		return lx.errorf("expected '.' or ']' to end table name, "+
+			"but got %q instead", r)
+	}
+}
+
+// lexKeyStart consumes a key name up until the first non-whitespace character.
+// lexKeyStart will ignore whitespace.
+func lexKeyStart(lx *lexer) stateFn {
+	r := lx.peek()
+	switch {
+	case r == keySep:
+		return lx.errorf("unexpected key separator %q", keySep)
+	case isWhitespace(r) || isNL(r):
+		lx.next()
+		return lexSkip(lx, lexKeyStart)
+	case r == stringStart || r == rawStringStart:
+		lx.ignore()
+		lx.emit(itemKeyStart)
+		lx.push(lexKeyEnd)
+		return lexValue // reuse string lexing
+	default:
+		lx.ignore()
+		lx.emit(itemKeyStart)
+		return lexBareKey
+	}
+}
+
+// lexBareKey consumes the text of a bare key. Assumes that the first character
+// (which is not whitespace) has not yet been consumed.
+func lexBareKey(lx *lexer) stateFn {
+	switch r := lx.next(); {
+	case isBareKeyChar(r):
+		return lexBareKey
+	case isWhitespace(r):
+		lx.backup()
+		lx.emit(itemText)
+		return lexKeyEnd
+	case r == keySep:
+		lx.backup()
+		lx.emit(itemText)
+		return lexKeyEnd
+	default:
+		return lx.errorf("bare keys cannot contain %q", r)
+	}
+}
+
+// lexKeyEnd consumes the end of a key and trims whitespace (up to the key
+// separator).
+func lexKeyEnd(lx *lexer) stateFn {
+	switch r := lx.next(); {
+	case r == keySep:
+		return lexSkip(lx, lexValue)
+	case isWhitespace(r):
+		return lexSkip(lx, lexKeyEnd)
+	default:
+		return lx.errorf("expected key separator %q, but got %q instead",
+			keySep, r)
+	}
+}
+
+// lexValue starts the consumption of a value anywhere a value is expected.
+// lexValue will ignore whitespace.
+// After a value is lexed, the last state on the next is popped and returned.
+func lexValue(lx *lexer) stateFn {
+	// We allow whitespace to precede a value, but NOT newlines.
+	// In array syntax, the array states are responsible for ignoring newlines.
+	r := lx.next()
+	switch {
+	case isWhitespace(r):
+		return lexSkip(lx, lexValue)
+	case isDigit(r):
+		lx.backup() // avoid an extra state and use the same as above
+		return lexNumberOrDateStart
+	}
+	switch r {
+	case arrayStart:
+		lx.ignore()
+		lx.emit(itemArray)
+		return lexArrayValue
+	case inlineTableStart:
+		lx.ignore()
+		lx.emit(itemInlineTableStart)
+		return lexInlineTableValue
+	case stringStart:
+		if lx.accept(stringStart) {
+			if lx.accept(stringStart) {
+				lx.ignore() // Ignore """
+				return lexMultilineString
+			}
+			lx.backup()
+		}
+		lx.ignore() // ignore the '"'
+		return lexString
+	case rawStringStart:
+		if lx.accept(rawStringStart) {
+			if lx.accept(rawStringStart) {
+				lx.ignore() // Ignore """
+				return lexMultilineRawString
+			}
+			lx.backup()
+		}
+		lx.ignore() // ignore the "'"
+		return lexRawString
+	case '+', '-':
+		return lexNumberStart
+	case '.': // special error case, be kind to users
+		return lx.errorf("floats must start with a digit, not '.'")
+	}
+	if unicode.IsLetter(r) {
+		// Be permissive here; lexBool will give a nice error if the
+		// user wrote something like
+		//   x = foo
+		// (i.e. not 'true' or 'false' but is something else word-like.)
+		lx.backup()
+		return lexBool
+	}
+	return lx.errorf("expected value but found %q instead", r)
+}
+
+// lexArrayValue consumes one value in an array. It assumes that '[' or ','
+// have already been consumed. All whitespace and newlines are ignored.
+func lexArrayValue(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case isWhitespace(r) || isNL(r):
+		return lexSkip(lx, lexArrayValue)
+	case r == commentStart:
+		lx.push(lexArrayValue)
+		return lexCommentStart
+	case r == comma:
+		return lx.errorf("unexpected comma")
+	case r == arrayEnd:
+		// NOTE(caleb): The spec isn't clear about whether you can have
+		// a trailing comma or not, so we'll allow it.
+		return lexArrayEnd
+	}
+
+	lx.backup()
+	lx.push(lexArrayValueEnd)
+	return lexValue
+}
+
+// lexArrayValueEnd consumes everything between the end of an array value and
+// the next value (or the end of the array): it ignores whitespace and newlines
+// and expects either a ',' or a ']'.
+func lexArrayValueEnd(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case isWhitespace(r) || isNL(r):
+		return lexSkip(lx, lexArrayValueEnd)
+	case r == commentStart:
+		lx.push(lexArrayValueEnd)
+		return lexCommentStart
+	case r == comma:
+		lx.ignore()
+		return lexArrayValue // move on to the next value
+	case r == arrayEnd:
+		return lexArrayEnd
+	}
+	return lx.errorf(
+		"expected a comma or array terminator %q, but got %q instead",
+		arrayEnd, r,
+	)
+}
+
+// lexArrayEnd finishes the lexing of an array.
+// It assumes that a ']' has just been consumed.
+func lexArrayEnd(lx *lexer) stateFn {
+	lx.ignore()
+	lx.emit(itemArrayEnd)
+	return lx.pop()
+}
+
+// lexInlineTableValue consumes one key/value pair in an inline table.
+// It assumes that '{' or ',' have already been consumed. Whitespace is ignored.
+func lexInlineTableValue(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case isWhitespace(r):
+		return lexSkip(lx, lexInlineTableValue)
+	case isNL(r):
+		return lx.errorf("newlines not allowed within inline tables")
+	case r == commentStart:
+		lx.push(lexInlineTableValue)
+		return lexCommentStart
+	case r == comma:
+		return lx.errorf("unexpected comma")
+	case r == inlineTableEnd:
+		return lexInlineTableEnd
+	}
+	lx.backup()
+	lx.push(lexInlineTableValueEnd)
+	return lexKeyStart
+}
+
+// lexInlineTableValueEnd consumes everything between the end of an inline table
+// key/value pair and the next pair (or the end of the table):
+// it ignores whitespace and expects either a ',' or a '}'.
+func lexInlineTableValueEnd(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case isWhitespace(r):
+		return lexSkip(lx, lexInlineTableValueEnd)
+	case isNL(r):
+		return lx.errorf("newlines not allowed within inline tables")
+	case r == commentStart:
+		lx.push(lexInlineTableValueEnd)
+		return lexCommentStart
+	case r == comma:
+		lx.ignore()
+		return lexInlineTableValue
+	case r == inlineTableEnd:
+		return lexInlineTableEnd
+	}
+	return lx.errorf("expected a comma or an inline table terminator %q, "+
+		"but got %q instead", inlineTableEnd, r)
+}
+
+// lexInlineTableEnd finishes the lexing of an inline table.
+// It assumes that a '}' has just been consumed.
+func lexInlineTableEnd(lx *lexer) stateFn {
+	lx.ignore()
+	lx.emit(itemInlineTableEnd)
+	return lx.pop()
+}
+
+// lexString consumes the inner contents of a string. It assumes that the
+// beginning '"' has already been consumed and ignored.
+func lexString(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case r == eof:
+		return lx.errorf("unexpected EOF")
+	case isNL(r):
+		return lx.errorf("strings cannot contain newlines")
+	case r == '\\':
+		lx.push(lexString)
+		return lexStringEscape
+	case r == stringEnd:
+		lx.backup()
+		lx.emit(itemString)
+		lx.next()
+		lx.ignore()
+		return lx.pop()
+	}
+	return lexString
+}
+
+// lexMultilineString consumes the inner contents of a string. It assumes that
+// the beginning '"""' has already been consumed and ignored.
+func lexMultilineString(lx *lexer) stateFn {
+	switch lx.next() {
+	case eof:
+		return lx.errorf("unexpected EOF")
+	case '\\':
+		return lexMultilineStringEscape
+	case stringEnd:
+		if lx.accept(stringEnd) {
+			if lx.accept(stringEnd) {
+				lx.backup()
+				lx.backup()
+				lx.backup()
+				lx.emit(itemMultilineString)
+				lx.next()
+				lx.next()
+				lx.next()
+				lx.ignore()
+				return lx.pop()
+			}
+			lx.backup()
+		}
+	}
+	return lexMultilineString
+}
+
+// lexRawString consumes a raw string. Nothing can be escaped in such a string.
+// It assumes that the beginning "'" has already been consumed and ignored.
+func lexRawString(lx *lexer) stateFn {
+	r := lx.next()
+	switch {
+	case r == eof:
+		return lx.errorf("unexpected EOF")
+	case isNL(r):
+		return lx.errorf("strings cannot contain newlines")
+	case r == rawStringEnd:
+		lx.backup()
+		lx.emit(itemRawString)
+		lx.next()
+		lx.ignore()
+		return lx.pop()
+	}
+	return lexRawString
+}
+
+// lexMultilineRawString consumes a raw string. Nothing can be escaped in such
+// a string. It assumes that the beginning "'''" has already been consumed and
+// ignored.
+func lexMultilineRawString(lx *lexer) stateFn {
+	switch lx.next() {
+	case eof:
+		return lx.errorf("unexpected EOF")
+	case rawStringEnd:
+		if lx.accept(rawStringEnd) {
+			if lx.accept(rawStringEnd) {
+				lx.backup()
+				lx.backup()
+				lx.backup()
+				lx.emit(itemRawMultilineString)
+				lx.next()
+				lx.next()
+				lx.next()
+				lx.ignore()
+				return lx.pop()
+			}
+			lx.backup()
+		}
+	}
+	return lexMultilineRawString
+}
+
+// lexMultilineStringEscape consumes an escaped character. It assumes that the
+// preceding '\\' has already been consumed.
+func lexMultilineStringEscape(lx *lexer) stateFn {
+	// Handle the special case first:
+	if isNL(lx.next()) {
+		return lexMultilineString
+	}
+	lx.backup()
+	lx.push(lexMultilineString)
+	return lexStringEscape(lx)
+}
+
+func lexStringEscape(lx *lexer) stateFn {
+	r := lx.next()
+	switch r {
+	case 'b':
+		fallthrough
+	case 't':
+		fallthrough
+	case 'n':
+		fallthrough
+	case 'f':
+		fallthrough
+	case 'r':
+		fallthrough
+	case '"':
+		fallthrough
+	case '\\':
+		return lx.pop()
+	case 'u':
+		return lexShortUnicodeEscape
+	case 'U':
+		return lexLongUnicodeEscape
+	}
+	return lx.errorf("invalid escape character %q; only the following "+
+		"escape characters are allowed: "+
+		`\b, \t, \n, \f, \r, \", \\, \uXXXX, and \UXXXXXXXX`, r)
+}
+
+func lexShortUnicodeEscape(lx *lexer) stateFn {
+	var r rune
+	for i := 0; i < 4; i++ {
+		r = lx.next()
+		if !isHexadecimal(r) {
+			return lx.errorf(`expected four hexadecimal digits after '\u', `+
+				"but got %q instead", lx.current())
+		}
+	}
+	return lx.pop()
+}
+
+func lexLongUnicodeEscape(lx *lexer) stateFn {
+	var r rune
+	for i := 0; i < 8; i++ {
+		r = lx.next()
+		if !isHexadecimal(r) {
+			return lx.errorf(`expected eight hexadecimal digits after '\U', `+
+				"but got %q instead", lx.current())
+		}
+	}
+	return lx.pop()
+}
+
+// lexNumberOrDateStart consumes either an integer, a float, or datetime.
+func lexNumberOrDateStart(lx *lexer) stateFn {
+	r := lx.next()
+	if isDigit(r) {
+		return lexNumberOrDate
+	}
+	switch r {
+	case '_':
+		return lexNumber
+	case 'e', 'E':
+		return lexFloat
+	case '.':
+		return lx.errorf("floats must start with a digit, not '.'")
+	}
+	return lx.errorf("expected a digit but got %q", r)
+}
+
+// lexNumberOrDate consumes either an integer, float or datetime.
+func lexNumberOrDate(lx *lexer) stateFn {
+	r := lx.next()
+	if isDigit(r) {
+		return lexNumberOrDate
+	}
+	switch r {
+	case '-':
+		return lexDatetime
+	case '_':
+		return lexNumber
+	case '.', 'e', 'E':
+		return lexFloat
+	}
+
+	lx.backup()
+	lx.emit(itemInteger)
+	return lx.pop()
+}
+
+// lexDatetime consumes a Datetime, to a first approximation.
+// The parser validates that it matches one of the accepted formats.
+func lexDatetime(lx *lexer) stateFn {
+	r := lx.next()
+	if isDigit(r) {
+		return lexDatetime
+	}
+	switch r {
+	case '-', 'T', ':', '.', 'Z', '+':
+		return lexDatetime
+	}
+
+	lx.backup()
+	lx.emit(itemDatetime)
+	return lx.pop()
+}
+
+// lexNumberStart consumes either an integer or a float. It assumes that a sign
+// has already been read, but that *no* digits have been consumed.
+// lexNumberStart will move to the appropriate integer or float states.
+func lexNumberStart(lx *lexer) stateFn {
+	// We MUST see a digit. Even floats have to start with a digit.
+	r := lx.next()
+	if !isDigit(r) {
+		if r == '.' {
+			return lx.errorf("floats must start with a digit, not '.'")
+		}
+		return lx.errorf("expected a digit but got %q", r)
+	}
+	return lexNumber
+}
+
+// lexNumber consumes an integer or a float after seeing the first digit.
+func lexNumber(lx *lexer) stateFn {
+	r := lx.next()
+	if isDigit(r) {
+		return lexNumber
+	}
+	switch r {
+	case '_':
+		return lexNumber
+	case '.', 'e', 'E':
+		return lexFloat
+	}
+
+	lx.backup()
+	lx.emit(itemInteger)
+	return lx.pop()
+}
+
+// lexFloat consumes the elements of a float. It allows any sequence of
+// float-like characters, so floats emitted by the lexer are only a first
+// approximation and must be validated by the parser.
+func lexFloat(lx *lexer) stateFn {
+	r := lx.next()
+	if isDigit(r) {
+		return lexFloat
+	}
+	switch r {
+	case '_', '.', '-', '+', 'e', 'E':
+		return lexFloat
+	}
+
+	lx.backup()
+	lx.emit(itemFloat)
+	return lx.pop()
+}
+
+// lexBool consumes a bool string: 'true' or 'false.
+func lexBool(lx *lexer) stateFn {
+	var rs []rune
+	for {
+		r := lx.next()
+		if !unicode.IsLetter(r) {
+			lx.backup()
+			break
+		}
+		rs = append(rs, r)
+	}
+	s := string(rs)
+	switch s {
+	case "true", "false":
+		lx.emit(itemBool)
+		return lx.pop()
+	}
+	return lx.errorf("expected value but found %q instead", s)
+}
+
+// lexCommentStart begins the lexing of a comment. It will emit
+// itemCommentStart and consume no characters, passing control to lexComment.
+func lexCommentStart(lx *lexer) stateFn {
+	lx.ignore()
+	lx.emit(itemCommentStart)
+	return lexComment
+}
+
+// lexComment lexes an entire comment. It assumes that '#' has been consumed.
+// It will consume *up to* the first newline character, and pass control
+// back to the last state on the stack.
+func lexComment(lx *lexer) stateFn {
+	r := lx.peek()
+	if isNL(r) || r == eof {
+		lx.emit(itemText)
+		return lx.pop()
+	}
+	lx.next()
+	return lexComment
+}
+
+// lexSkip ignores all slurped input and moves on to the next state.
+func lexSkip(lx *lexer, nextState stateFn) stateFn {
+	return func(lx *lexer) stateFn {
+		lx.ignore()
+		return nextState
+	}
+}
+
+// isWhitespace returns true if `r` is a whitespace character according
+// to the spec.
+func isWhitespace(r rune) bool {
+	return r == '\t' || r == ' '
+}
+
+func isNL(r rune) bool {
+	return r == '\n' || r == '\r'
+}
+
+func isDigit(r rune) bool {
+	return r >= '0' && r <= '9'
+}
+
+func isHexadecimal(r rune) bool {
+	return (r >= '0' && r <= '9') ||
+		(r >= 'a' && r <= 'f') ||
+		(r >= 'A' && r <= 'F')
+}
+
+func isBareKeyChar(r rune) bool {
+	return (r >= 'A' && r <= 'Z') ||
+		(r >= 'a' && r <= 'z') ||
+		(r >= '0' && r <= '9') ||
+		r == '_' ||
+		r == '-'
+}
+
+func (itype itemType) String() string {
+	switch itype {
+	case itemError:
+		return "Error"
+	case itemNIL:
+		return "NIL"
+	case itemEOF:
+		return "EOF"
+	case itemText:
+		return "Text"
+	case itemString, itemRawString, itemMultilineString, itemRawMultilineString:
+		return "String"
+	case itemBool:
+		return "Bool"
+	case itemInteger:
+		return "Integer"
+	case itemFloat:
+		return "Float"
+	case itemDatetime:
+		return "DateTime"
+	case itemTableStart:
+		return "TableStart"
+	case itemTableEnd:
+		return "TableEnd"
+	case itemKeyStart:
+		return "KeyStart"
+	case itemArray:
+		return "Array"
+	case itemArrayEnd:
+		return "ArrayEnd"
+	case itemCommentStart:
+		return "CommentStart"
+	}
+	panic(fmt.Sprintf("BUG: Unknown type '%d'.", int(itype)))
+}
+
+func (item item) String() string {
+	return fmt.Sprintf("(%s, %s)", item.typ.String(), item.val)
+}

vendor/github.com/BurntSushi/toml/parse.go

@@ -0,0 +1,592 @@
+package toml
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+	"unicode"
+	"unicode/utf8"
+)
+
+type parser struct {
+	mapping map[string]interface{}
+	types   map[string]tomlType
+	lx      *lexer
+
+	// A list of keys in the order that they appear in the TOML data.
+	ordered []Key
+
+	// the full key for the current hash in scope
+	context Key
+
+	// the base key name for everything except hashes
+	currentKey string
+
+	// rough approximation of line number
+	approxLine int
+
+	// A map of 'key.group.names' to whether they were created implicitly.
+	implicits map[string]bool
+}
+
+type parseError string
+
+func (pe parseError) Error() string {
+	return string(pe)
+}
+
+func parse(data string) (p *parser, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			var ok bool
+			if err, ok = r.(parseError); ok {
+				return
+			}
+			panic(r)
+		}
+	}()
+
+	p = &parser{
+		mapping:   make(map[string]interface{}),
+		types:     make(map[string]tomlType),
+		lx:        lex(data),
+		ordered:   make([]Key, 0),
+		implicits: make(map[string]bool),
+	}
+	for {
+		item := p.next()
+		if item.typ == itemEOF {
+			break
+		}
+		p.topLevel(item)
+	}
+
+	return p, nil
+}
+
+func (p *parser) panicf(format string, v ...interface{}) {
+	msg := fmt.Sprintf("Near line %d (last key parsed '%s'): %s",
+		p.approxLine, p.current(), fmt.Sprintf(format, v...))
+	panic(parseError(msg))
+}
+
+func (p *parser) next() item {
+	it := p.lx.nextItem()
+	if it.typ == itemError {
+		p.panicf("%s", it.val)
+	}
+	return it
+}
+
+func (p *parser) bug(format string, v ...interface{}) {
+	panic(fmt.Sprintf("BUG: "+format+"\n\n", v...))
+}
+
+func (p *parser) expect(typ itemType) item {
+	it := p.next()
+	p.assertEqual(typ, it.typ)
+	return it
+}
+
+func (p *parser) assertEqual(expected, got itemType) {
+	if expected != got {
+		p.bug("Expected '%s' but got '%s'.", expected, got)
+	}
+}
+
+func (p *parser) topLevel(item item) {
+	switch item.typ {
+	case itemCommentStart:
+		p.approxLine = item.line
+		p.expect(itemText)
+	case itemTableStart:
+		kg := p.next()
+		p.approxLine = kg.line
+
+		var key Key
+		for ; kg.typ != itemTableEnd && kg.typ != itemEOF; kg = p.next() {
+			key = append(key, p.keyString(kg))
+		}
+		p.assertEqual(itemTableEnd, kg.typ)
+
+		p.establishContext(key, false)
+		p.setType("", tomlHash)
+		p.ordered = append(p.ordered, key)
+	case itemArrayTableStart:
+		kg := p.next()
+		p.approxLine = kg.line
+
+		var key Key
+		for ; kg.typ != itemArrayTableEnd && kg.typ != itemEOF; kg = p.next() {
+			key = append(key, p.keyString(kg))
+		}
+		p.assertEqual(itemArrayTableEnd, kg.typ)
+
+		p.establishContext(key, true)
+		p.setType("", tomlArrayHash)
+		p.ordered = append(p.ordered, key)
+	case itemKeyStart:
+		kname := p.next()
+		p.approxLine = kname.line
+		p.currentKey = p.keyString(kname)
+
+		val, typ := p.value(p.next())
+		p.setValue(p.currentKey, val)
+		p.setType(p.currentKey, typ)
+		p.ordered = append(p.ordered, p.context.add(p.currentKey))
+		p.currentKey = ""
+	default:
+		p.bug("Unexpected type at top level: %s", item.typ)
+	}
+}
+
+// Gets a string for a key (or part of a key in a table name).
+func (p *parser) keyString(it item) string {
+	switch it.typ {
+	case itemText:
+		return it.val
+	case itemString, itemMultilineString,
+		itemRawString, itemRawMultilineString:
+		s, _ := p.value(it)
+		return s.(string)
+	default:
+		p.bug("Unexpected key type: %s", it.typ)
+		panic("unreachable")
+	}
+}
+
+// value translates an expected value from the lexer into a Go value wrapped
+// as an empty interface.
+func (p *parser) value(it item) (interface{}, tomlType) {
+	switch it.typ {
+	case itemString:
+		return p.replaceEscapes(it.val), p.typeOfPrimitive(it)
+	case itemMultilineString:
+		trimmed := stripFirstNewline(stripEscapedWhitespace(it.val))
+		return p.replaceEscapes(trimmed), p.typeOfPrimitive(it)
+	case itemRawString:
+		return it.val, p.typeOfPrimitive(it)
+	case itemRawMultilineString:
+		return stripFirstNewline(it.val), p.typeOfPrimitive(it)
+	case itemBool:
+		switch it.val {
+		case "true":
+			return true, p.typeOfPrimitive(it)
+		case "false":
+			return false, p.typeOfPrimitive(it)
+		}
+		p.bug("Expected boolean value, but got '%s'.", it.val)
+	case itemInteger:
+		if !numUnderscoresOK(it.val) {
+			p.panicf("Invalid integer %q: underscores must be surrounded by digits",
+				it.val)
+		}
+		val := strings.Replace(it.val, "_", "", -1)
+		num, err := strconv.ParseInt(val, 10, 64)
+		if err != nil {
+			// Distinguish integer values. Normally, it'd be a bug if the lexer
+			// provides an invalid integer, but it's possible that the number is
+			// out of range of valid values (which the lexer cannot determine).
+			// So mark the former as a bug but the latter as a legitimate user
+			// error.
+			if e, ok := err.(*strconv.NumError); ok &&
+				e.Err == strconv.ErrRange {
+
+				p.panicf("Integer '%s' is out of the range of 64-bit "+
+					"signed integers.", it.val)
+			} else {
+				p.bug("Expected integer value, but got '%s'.", it.val)
+			}
+		}
+		return num, p.typeOfPrimitive(it)
+	case itemFloat:
+		parts := strings.FieldsFunc(it.val, func(r rune) bool {
+			switch r {
+			case '.', 'e', 'E':
+				return true
+			}
+			return false
+		})
+		for _, part := range parts {
+			if !numUnderscoresOK(part) {
+				p.panicf("Invalid float %q: underscores must be "+
+					"surrounded by digits", it.val)
+			}
+		}
+		if !numPeriodsOK(it.val) {
+			// As a special case, numbers like '123.' or '1.e2',
+			// which are valid as far as Go/strconv are concerned,
+			// must be rejected because TOML says that a fractional
+			// part consists of '.' followed by 1+ digits.
+			p.panicf("Invalid float %q: '.' must be followed "+
+				"by one or more digits", it.val)
+		}
+		val := strings.Replace(it.val, "_", "", -1)
+		num, err := strconv.ParseFloat(val, 64)
+		if err != nil {
+			if e, ok := err.(*strconv.NumError); ok &&
+				e.Err == strconv.ErrRange {
+
+				p.panicf("Float '%s' is out of the range of 64-bit "+
+					"IEEE-754 floating-point numbers.", it.val)
+			} else {
+				p.panicf("Invalid float value: %q", it.val)
+			}
+		}
+		return num, p.typeOfPrimitive(it)
+	case itemDatetime:
+		var t time.Time
+		var ok bool
+		var err error
+		for _, format := range []string{
+			"2006-01-02T15:04:05Z07:00",
+			"2006-01-02T15:04:05",
+			"2006-01-02",
+		} {
+			t, err = time.ParseInLocation(format, it.val, time.Local)
+			if err == nil {
+				ok = true
+				break
+			}
+		}
+		if !ok {
+			p.panicf("Invalid TOML Datetime: %q.", it.val)
+		}
+		return t, p.typeOfPrimitive(it)
+	case itemArray:
+		array := make([]interface{}, 0)
+		types := make([]tomlType, 0)
+
+		for it = p.next(); it.typ != itemArrayEnd; it = p.next() {
+			if it.typ == itemCommentStart {
+				p.expect(itemText)
+				continue
+			}
+
+			val, typ := p.value(it)
+			array = append(array, val)
+			types = append(types, typ)
+		}
+		return array, p.typeOfArray(types)
+	case itemInlineTableStart:
+		var (
+			hash         = make(map[string]interface{})
+			outerContext = p.context
+			outerKey     = p.currentKey
+		)
+
+		p.context = append(p.context, p.currentKey)
+		p.currentKey = ""
+		for it := p.next(); it.typ != itemInlineTableEnd; it = p.next() {
+			if it.typ != itemKeyStart {
+				p.bug("Expected key start but instead found %q, around line %d",
+					it.val, p.approxLine)
+			}
+			if it.typ == itemCommentStart {
+				p.expect(itemText)
+				continue
+			}
+
+			// retrieve key
+			k := p.next()
+			p.approxLine = k.line
+			kname := p.keyString(k)
+
+			// retrieve value
+			p.currentKey = kname
+			val, typ := p.value(p.next())
+			// make sure we keep metadata up to date
+			p.setType(kname, typ)
+			p.ordered = append(p.ordered, p.context.add(p.currentKey))
+			hash[kname] = val
+		}
+		p.context = outerContext
+		p.currentKey = outerKey
+		return hash, tomlHash
+	}
+	p.bug("Unexpected value type: %s", it.typ)
+	panic("unreachable")
+}
+
+// numUnderscoresOK checks whether each underscore in s is surrounded by
+// characters that are not underscores.
+func numUnderscoresOK(s string) bool {
+	accept := false
+	for _, r := range s {
+		if r == '_' {
+			if !accept {
+				return false
+			}
+			accept = false
+			continue
+		}
+		accept = true
+	}
+	return accept
+}
+
+// numPeriodsOK checks whether every period in s is followed by a digit.
+func numPeriodsOK(s string) bool {
+	period := false
+	for _, r := range s {
+		if period && !isDigit(r) {
+			return false
+		}
+		period = r == '.'
+	}
+	return !period
+}
+
+// establishContext sets the current context of the parser,
+// where the context is either a hash or an array of hashes. Which one is
+// set depends on the value of the `array` parameter.
+//
+// Establishing the context also makes sure that the key isn't a duplicate, and
+// will create implicit hashes automatically.
+func (p *parser) establishContext(key Key, array bool) {
+	var ok bool
+
+	// Always start at the top level and drill down for our context.
+	hashContext := p.mapping
+	keyContext := make(Key, 0)
+
+	// We only need implicit hashes for key[0:-1]
+	for _, k := range key[0 : len(key)-1] {
+		_, ok = hashContext[k]
+		keyContext = append(keyContext, k)
+
+		// No key? Make an implicit hash and move on.
+		if !ok {
+			p.addImplicit(keyContext)
+			hashContext[k] = make(map[string]interface{})
+		}
+
+		// If the hash context is actually an array of tables, then set
+		// the hash context to the last element in that array.
+		//
+		// Otherwise, it better be a table, since this MUST be a key group (by
+		// virtue of it not being the last element in a key).
+		switch t := hashContext[k].(type) {
+		case []map[string]interface{}:
+			hashContext = t[len(t)-1]
+		case map[string]interface{}:
+			hashContext = t
+		default:
+			p.panicf("Key '%s' was already created as a hash.", keyContext)
+		}
+	}
+
+	p.context = keyContext
+	if array {
+		// If this is the first element for this array, then allocate a new
+		// list of tables for it.
+		k := key[len(key)-1]
+		if _, ok := hashContext[k]; !ok {
+			hashContext[k] = make([]map[string]interface{}, 0, 5)
+		}
+
+		// Add a new table. But make sure the key hasn't already been used
+		// for something else.
+		if hash, ok := hashContext[k].([]map[string]interface{}); ok {
+			hashContext[k] = append(hash, make(map[string]interface{}))
+		} else {
+			p.panicf("Key '%s' was already created and cannot be used as "+
+				"an array.", keyContext)
+		}
+	} else {
+		p.setValue(key[len(key)-1], make(map[string]interface{}))
+	}
+	p.context = append(p.context, key[len(key)-1])
+}
+
+// setValue sets the given key to the given value in the current context.
+// It will make sure that the key hasn't already been defined, account for
+// implicit key groups.
+func (p *parser) setValue(key string, value interface{}) {
+	var tmpHash interface{}
+	var ok bool
+
+	hash := p.mapping
+	keyContext := make(Key, 0)
+	for _, k := range p.context {
+		keyContext = append(keyContext, k)
+		if tmpHash, ok = hash[k]; !ok {
+			p.bug("Context for key '%s' has not been established.", keyContext)
+		}
+		switch t := tmpHash.(type) {
+		case []map[string]interface{}:
+			// The context is a table of hashes. Pick the most recent table
+			// defined as the current hash.
+			hash = t[len(t)-1]
+		case map[string]interface{}:
+			hash = t
+		default:
+			p.bug("Expected hash to have type 'map[string]interface{}', but "+
+				"it has '%T' instead.", tmpHash)
+		}
+	}
+	keyContext = append(keyContext, key)
+
+	if _, ok := hash[key]; ok {
+		// Typically, if the given key has already been set, then we have
+		// to raise an error since duplicate keys are disallowed. However,
+		// it's possible that a key was previously defined implicitly. In this
+		// case, it is allowed to be redefined concretely. (See the
+		// `tests/valid/implicit-and-explicit-after.toml` test in `toml-test`.)
+		//
+		// But we have to make sure to stop marking it as an implicit. (So that
+		// another redefinition provokes an error.)
+		//
+		// Note that since it has already been defined (as a hash), we don't
+		// want to overwrite it. So our business is done.
+		if p.isImplicit(keyContext) {
+			p.removeImplicit(keyContext)
+			return
+		}
+
+		// Otherwise, we have a concrete key trying to override a previous
+		// key, which is *always* wrong.
+		p.panicf("Key '%s' has already been defined.", keyContext)
+	}
+	hash[key] = value
+}
+
+// setType sets the type of a particular value at a given key.
+// It should be called immediately AFTER setValue.
+//
+// Note that if `key` is empty, then the type given will be applied to the
+// current context (which is either a table or an array of tables).
+func (p *parser) setType(key string, typ tomlType) {
+	keyContext := make(Key, 0, len(p.context)+1)
+	for _, k := range p.context {
+		keyContext = append(keyContext, k)
+	}
+	if len(key) > 0 { // allow type setting for hashes
+		keyContext = append(keyContext, key)
+	}
+	p.types[keyContext.String()] = typ
+}
+
+// addImplicit sets the given Key as having been created implicitly.
+func (p *parser) addImplicit(key Key) {
+	p.implicits[key.String()] = true
+}
+
+// removeImplicit stops tagging the given key as having been implicitly
+// created.
+func (p *parser) removeImplicit(key Key) {
+	p.implicits[key.String()] = false
+}
+
+// isImplicit returns true if the key group pointed to by the key was created
+// implicitly.
+func (p *parser) isImplicit(key Key) bool {
+	return p.implicits[key.String()]
+}
+
+// current returns the full key name of the current context.
+func (p *parser) current() string {
+	if len(p.currentKey) == 0 {
+		return p.context.String()
+	}
+	if len(p.context) == 0 {
+		return p.currentKey
+	}
+	return fmt.Sprintf("%s.%s", p.context, p.currentKey)
+}
+
+func stripFirstNewline(s string) string {
+	if len(s) == 0 || s[0] != '\n' {
+		return s
+	}
+	return s[1:]
+}
+
+func stripEscapedWhitespace(s string) string {
+	esc := strings.Split(s, "\\\n")
+	if len(esc) > 1 {
+		for i := 1; i < len(esc); i++ {
+			esc[i] = strings.TrimLeftFunc(esc[i], unicode.IsSpace)
+		}
+	}
+	return strings.Join(esc, "")
+}
+
+func (p *parser) replaceEscapes(str string) string {
+	var replaced []rune
+	s := []byte(str)
+	r := 0
+	for r < len(s) {
+		if s[r] != '\\' {
+			c, size := utf8.DecodeRune(s[r:])
+			r += size
+			replaced = append(replaced, c)
+			continue
+		}
+		r += 1
+		if r >= len(s) {
+			p.bug("Escape sequence at end of string.")
+			return ""
+		}
+		switch s[r] {
+		default:
+			p.bug("Expected valid escape code after \\, but got %q.", s[r])
+			return ""
+		case 'b':
+			replaced = append(replaced, rune(0x0008))
+			r += 1
+		case 't':
+			replaced = append(replaced, rune(0x0009))
+			r += 1
+		case 'n':
+			replaced = append(replaced, rune(0x000A))
+			r += 1
+		case 'f':
+			replaced = append(replaced, rune(0x000C))
+			r += 1
+		case 'r':
+			replaced = append(replaced, rune(0x000D))
+			r += 1
+		case '"':
+			replaced = append(replaced, rune(0x0022))
+			r += 1
+		case '\\':
+			replaced = append(replaced, rune(0x005C))
+			r += 1
+		case 'u':
+			// At this point, we know we have a Unicode escape of the form
+			// `uXXXX` at [r, r+5). (Because the lexer guarantees this
+			// for us.)
+			escaped := p.asciiEscapeToUnicode(s[r+1 : r+5])
+			replaced = append(replaced, escaped)
+			r += 5
+		case 'U':
+			// At this point, we know we have a Unicode escape of the form
+			// `uXXXX` at [r, r+9). (Because the lexer guarantees this
+			// for us.)
+			escaped := p.asciiEscapeToUnicode(s[r+1 : r+9])
+			replaced = append(replaced, escaped)
+			r += 9
+		}
+	}
+	return string(replaced)
+}
+
+func (p *parser) asciiEscapeToUnicode(bs []byte) rune {
+	s := string(bs)
+	hex, err := strconv.ParseUint(strings.ToLower(s), 16, 32)
+	if err != nil {
+		p.bug("Could not parse '%s' as a hexadecimal number, but the "+
+			"lexer claims it's OK: %s", s, err)
+	}
+	if !utf8.ValidRune(rune(hex)) {
+		p.panicf("Escaped character '\\u%s' is not valid UTF-8.", s)
+	}
+	return rune(hex)
+}
+
+func isStringType(ty itemType) bool {
+	return ty == itemString || ty == itemMultilineString ||
+		ty == itemRawString || ty == itemRawMultilineString
+}

vendor/github.com/BurntSushi/toml/session.vim

@@ -0,0 +1 @@
+au BufWritePost *.go silent!make tags > /dev/null 2>&1

vendor/github.com/BurntSushi/toml/type_check.go

@@ -0,0 +1,91 @@
+package toml
+
+// tomlType represents any Go type that corresponds to a TOML type.
+// While the first draft of the TOML spec has a simplistic type system that
+// probably doesn't need this level of sophistication, we seem to be militating
+// toward adding real composite types.
+type tomlType interface {
+	typeString() string
+}
+
+// typeEqual accepts any two types and returns true if they are equal.
+func typeEqual(t1, t2 tomlType) bool {
+	if t1 == nil || t2 == nil {
+		return false
+	}
+	return t1.typeString() == t2.typeString()
+}
+
+func typeIsHash(t tomlType) bool {
+	return typeEqual(t, tomlHash) || typeEqual(t, tomlArrayHash)
+}
+
+type tomlBaseType string
+
+func (btype tomlBaseType) typeString() string {
+	return string(btype)
+}
+
+func (btype tomlBaseType) String() string {
+	return btype.typeString()
+}
+
+var (
+	tomlInteger   tomlBaseType = "Integer"
+	tomlFloat     tomlBaseType = "Float"
+	tomlDatetime  tomlBaseType = "Datetime"
+	tomlString    tomlBaseType = "String"
+	tomlBool      tomlBaseType = "Bool"
+	tomlArray     tomlBaseType = "Array"
+	tomlHash      tomlBaseType = "Hash"
+	tomlArrayHash tomlBaseType = "ArrayHash"
+)
+
+// typeOfPrimitive returns a tomlType of any primitive value in TOML.
+// Primitive values are: Integer, Float, Datetime, String and Bool.
+//
+// Passing a lexer item other than the following will cause a BUG message
+// to occur: itemString, itemBool, itemInteger, itemFloat, itemDatetime.
+func (p *parser) typeOfPrimitive(lexItem item) tomlType {
+	switch lexItem.typ {
+	case itemInteger:
+		return tomlInteger
+	case itemFloat:
+		return tomlFloat
+	case itemDatetime:
+		return tomlDatetime
+	case itemString:
+		return tomlString
+	case itemMultilineString:
+		return tomlString
+	case itemRawString:
+		return tomlString
+	case itemRawMultilineString:
+		return tomlString
+	case itemBool:
+		return tomlBool
+	}
+	p.bug("Cannot infer primitive type of lex item '%s'.", lexItem)
+	panic("unreachable")
+}
+
+// typeOfArray returns a tomlType for an array given a list of types of its
+// values.
+//
+// In the current spec, if an array is homogeneous, then its type is always
+// "Array". If the array is not homogeneous, an error is generated.
+func (p *parser) typeOfArray(types []tomlType) tomlType {
+	// Empty arrays are cool.
+	if len(types) == 0 {
+		return tomlArray
+	}
+
+	theType := types[0]
+	for _, t := range types[1:] {
+		if !typeEqual(theType, t) {
+			p.panicf("Array contains values of type '%s' and '%s', but "+
+				"arrays must be homogeneous.", theType, t)
+		}
+	}
+	return tomlArray
+}

vendor/github.com/BurntSushi/toml/type_fields.go

@@ -0,0 +1,242 @@
+package toml
+
+// Struct field handling is adapted from code in encoding/json:
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the Go distribution.
+
+import (
+	"reflect"
+	"sort"
+	"sync"
+)
+
+// A field represents a single field found in a struct.
+type field struct {
+	name  string       // the name of the field (`toml` tag included)
+	tag   bool         // whether field has a `toml` tag
+	index []int        // represents the depth of an anonymous field
+	typ   reflect.Type // the type of the field
+}
+
+// byName sorts field by name, breaking ties with depth,
+// then breaking ties with "name came from toml tag", then
+// breaking ties with index sequence.
+type byName []field
+
+func (x byName) Len() int { return len(x) }
+
+func (x byName) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x byName) Less(i, j int) bool {
+	if x[i].name != x[j].name {
+		return x[i].name < x[j].name
+	}
+	if len(x[i].index) != len(x[j].index) {
+		return len(x[i].index) < len(x[j].index)
+	}
+	if x[i].tag != x[j].tag {
+		return x[i].tag
+	}
+	return byIndex(x).Less(i, j)
+}
+
+// byIndex sorts field by index sequence.
+type byIndex []field
+
+func (x byIndex) Len() int { return len(x) }
+
+func (x byIndex) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+func (x byIndex) Less(i, j int) bool {
+	for k, xik := range x[i].index {
+		if k >= len(x[j].index) {
+			return false
+		}
+		if xik != x[j].index[k] {
+			return xik < x[j].index[k]
+		}
+	}
+	return len(x[i].index) < len(x[j].index)
+}
+
+// typeFields returns a list of fields that TOML should recognize for the given
+// type. The algorithm is breadth-first search over the set of structs to
+// include - the top struct and then any reachable anonymous structs.
+func typeFields(t reflect.Type) []field {
+	// Anonymous fields to explore at the current level and the next.
+	current := []field{}
+	next := []field{{typ: t}}
+
+	// Count of queued names for current level and the next.
+	count := map[reflect.Type]int{}
+	nextCount := map[reflect.Type]int{}
+
+	// Types already visited at an earlier level.
+	visited := map[reflect.Type]bool{}
+
+	// Fields found.
+	var fields []field
+
+	for len(next) > 0 {
+		current, next = next, current[:0]
+		count, nextCount = nextCount, map[reflect.Type]int{}
+
+		for _, f := range current {
+			if visited[f.typ] {
+				continue
+			}
+			visited[f.typ] = true
+
+			// Scan f.typ for fields to include.
+			for i := 0; i < f.typ.NumField(); i++ {
+				sf := f.typ.Field(i)
+				if sf.PkgPath != "" && !sf.Anonymous { // unexported
+					continue
+				}
+				opts := getOptions(sf.Tag)
+				if opts.skip {
+					continue
+				}
+				index := make([]int, len(f.index)+1)
+				copy(index, f.index)
+				index[len(f.index)] = i
+
+				ft := sf.Type
+				if ft.Name() == "" && ft.Kind() == reflect.Ptr {
+					// Follow pointer.
+					ft = ft.Elem()
+				}
+
+				// Record found field and index sequence.
+				if opts.name != "" || !sf.Anonymous || ft.Kind() != reflect.Struct {
+					tagged := opts.name != ""
+					name := opts.name
+					if name == "" {
+						name = sf.Name
+					}
+					fields = append(fields, field{name, tagged, index, ft})
+					if count[f.typ] > 1 {
+						// If there were multiple instances, add a second,
+						// so that the annihilation code will see a duplicate.
+						// It only cares about the distinction between 1 or 2,
+						// so don't bother generating any more copies.
+						fields = append(fields, fields[len(fields)-1])
+					}
+					continue
+				}
+
+				// Record new anonymous struct to explore in next round.
+				nextCount[ft]++
+				if nextCount[ft] == 1 {
+					f := field{name: ft.Name(), index: index, typ: ft}
+					next = append(next, f)
+				}
+			}
+		}
+	}
+
+	sort.Sort(byName(fields))
+
+	// Delete all fields that are hidden by the Go rules for embedded fields,
+	// except that fields with TOML tags are promoted.
+
+	// The fields are sorted in primary order of name, secondary order
+	// of field index length. Loop over names; for each name, delete
+	// hidden fields by choosing the one dominant field that survives.
+	out := fields[:0]
+	for advance, i := 0, 0; i < len(fields); i += advance {
+		// One iteration per name.
+		// Find the sequence of fields with the name of this first field.
+		fi := fields[i]
+		name := fi.name
+		for advance = 1; i+advance < len(fields); advance++ {
+			fj := fields[i+advance]
+			if fj.name != name {
+				break
+			}
+		}
+		if advance == 1 { // Only one field with this name
+			out = append(out, fi)
+			continue
+		}
+		dominant, ok := dominantField(fields[i : i+advance])
+		if ok {
+			out = append(out, dominant)
+		}
+	}
+
+	fields = out
+	sort.Sort(byIndex(fields))
+
+	return fields
+}
+
+// dominantField looks through the fields, all of which are known to
+// have the same name, to find the single field that dominates the
+// others using Go's embedding rules, modified by the presence of
+// TOML tags. If there are multiple top-level fields, the boolean
+// will be false: This condition is an error in Go and we skip all
+// the fields.
+func dominantField(fields []field) (field, bool) {
+	// The fields are sorted in increasing index-length order. The winner
+	// must therefore be one with the shortest index length. Drop all
+	// longer entries, which is easy: just truncate the slice.
+	length := len(fields[0].index)
+	tagged := -1 // Index of first tagged field.
+	for i, f := range fields {
+		if len(f.index) > length {
+			fields = fields[:i]
+			break
+		}
+		if f.tag {
+			if tagged >= 0 {
+				// Multiple tagged fields at the same level: conflict.
+				// Return no field.
+				return field{}, false
+			}
+			tagged = i
+		}
+	}
+	if tagged >= 0 {
+		return fields[tagged], true
+	}
+	// All remaining fields have the same length. If there's more than one,
+	// we have a conflict (two fields named "X" at the same level) and we
+	// return no field.
+	if len(fields) > 1 {
+		return field{}, false
+	}
+	return fields[0], true
+}
+
+var fieldCache struct {
+	sync.RWMutex
+	m map[reflect.Type][]field
+}
+
+// cachedTypeFields is like typeFields but uses a cache to avoid repeated work.
+func cachedTypeFields(t reflect.Type) []field {
+	fieldCache.RLock()
+	f := fieldCache.m[t]
+	fieldCache.RUnlock()
+	if f != nil {
+		return f
+	}
+
+	// Compute fields without lock.
+	// Might duplicate effort but won't hold other computations back.
+	f = typeFields(t)
+	if f == nil {
+		f = []field{}
+	}
+
+	fieldCache.Lock()
+	if fieldCache.m == nil {
+		fieldCache.m = map[reflect.Type][]field{}
+	}
+	fieldCache.m[t] = f
+	fieldCache.Unlock()
+	return f
+}

vendor/github.com/adrg/frontmatter/CODE_OF_CONDUCT.md

@@ -0,0 +1,77 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age,
+body size, disability, ethnicity, sex characteristics, gender identity and
+expression, level of experience, education, socio-economic status, nationality,
+personal appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behaviour that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behaviour by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behaviour and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behaviour.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviour that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behaviour may be
+reported by contacting the project team at adrg@epistack.com. All complaints
+will be reviewed and investigated and will result in a response that is deemed
+necessary and appropriate to the circumstances. The project team is obligated to
+maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 1.4, available at
+https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq

vendor/github.com/adrg/frontmatter/CONTRIBUTING.md

@@ -0,0 +1,135 @@
+# Contributing to this project
+
+Contributions in the form of pull requests, issues or just general feedback,
+are always welcome. Please take a moment to review this document in order to
+make the contribution process easy and effective for everyone involved.
+
+Following these guidelines helps to communicate that you respect the time of
+the developers managing and developing this open source project. In return,
+they should reciprocate that respect in addressing your issue or assessing
+patches and features.
+
+## Using the issue tracker
+
+The issue tracker is the preferred channel for [bug reports](#bugs),
+[features requests](#features) and [submitting pull
+requests](#pull-requests), but please respect the following restrictions:
+
+* Please **do not** use the issue tracker for personal support requests (use
+  [Stack Overflow](http://stackoverflow.com) or IRC).
+* Please **do not** derail or troll issues. Keep the discussion on topic and
+  respect the opinions of others.
+
+<a name="bugs"></a>
+## Bug reports
+
+A bug is a _demonstrable problem_ that is caused by the code in the repository.
+Good bug reports are extremely helpful - thank you!
+
+Guidelines for bug reports:
+
+1. **Use the GitHub issue search** &mdash; check if the issue has already been
+   reported.
+2. **Check if the issue has been fixed** &mdash; try to reproduce it using the
+   latest `master` or development branch in the repository.
+3. **Isolate the problem** &mdash; create a reduced test case.
+
+A good bug report shouldn't leave others needing to chase you up for more
+information. Please try to be as detailed as possible in your report. What is
+your environment? What steps will reproduce the issue? What browser(s) and OS
+experience the problem? What would you expect to be the outcome? All these
+details will help people to fix any potential bugs.
+
+Example:
+
+> Short and descriptive example bug report title
+>
+> A summary of the issue and the browser/OS environment in which it occurs. If
+> suitable, include the steps required to reproduce the bug.
+>
+> 1. This is the first step
+> 2. This is the second step
+> 3. Further steps, etc.
+>
+> `<url>` - a link to the reduced test case
+>
+> Any other information you want to share that is relevant to the issue being
+> reported. This might include the lines of code that you have identified as
+> causing the bug, and potential solutions (and your opinions on their
+> merits).
+
+
+<a name="features"></a>
+## Feature requests
+
+Feature requests are welcome. But take a moment to find out whether your idea
+fits with the scope and aims of the project. It's up to *you* to make a strong
+case to convince the project's developers of the merits of this feature. Please
+provide as much detail and context as possible.
+
+
+<a name="pull-requests"></a>
+## Pull requests
+
+Good pull requests - patches, improvements, new features - are a fantastic
+help. They should remain focused in scope and avoid containing unrelated
+commits.
+
+**Please ask first** before embarking on any significant pull request (e.g.
+implementing features, refactoring code, porting to a different language),
+otherwise you risk spending a lot of time working on something that the
+project's developers might not want to merge into the project.
+
+Please adhere to the coding conventions used throughout a project (indentation,
+accurate comments, etc.) and any other requirements (such as test coverage).
+
+Follow this process if you'd like your work considered for inclusion in the
+project:
+
+1. [Fork](http://help.github.com/fork-a-repo/) the project, clone your fork,
+   and configure the remotes:
+
+   ```bash
+   # Clone your fork of the repo into the current directory
+   git clone https://github.com/<your-username>/<repo-name>
+   # Navigate to the newly cloned directory
+   cd <repo-name>
+   # Assign the original repo to a remote called "upstream"
+   git remote add upstream https://github.com/<upstream-owner>/<repo-name>
+   ```
+
+2. If you cloned a while ago, get the latest changes from upstream:
+
+   ```bash
+   git checkout <dev-branch>
+   git pull upstream <dev-branch>
+   ```
+
+3. Create a new topic branch (off the main project development branch) to
+   contain your feature, change, or fix:
+
+   ```bash
+   git checkout -b <topic-branch-name>
+   ```
+
+4. Commit your changes in logical chunks and use descriptive commit messages.
+   Use [interactive rebase](https://help.github.com/articles/interactive-rebase)
+   to tidy up your commits before making them public.
+
+5. Locally merge (or rebase) the upstream development branch into your topic branch:
+
+   ```bash
+   git pull [--rebase] upstream <dev-branch>
+   ```
+
+6. Push your topic branch up to your fork:
+
+   ```bash
+   git push origin <topic-branch-name>
+   ```
+
+7. [Open a Pull Request](https://help.github.com/articles/using-pull-requests/)
+    with a clear title and description.
+
+**IMPORTANT**: By submitting a patch, you agree to allow the project owner to
+license your work under the same license as that used by the project.

vendor/github.com/adrg/frontmatter/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2020 Adrian-George Bostan <adrg@epistack.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/adrg/frontmatter/README.md

@@ -0,0 +1,170 @@
+<h1 align="center">
+  <div>
+    <img src="https://raw.githubusercontent.com/adrg/adrg.github.io/master/assets/projects/frontmatter/logo.png" width="120px" alt="frontmatter logo"/>
+  </div>
+  frontmatter
+</h1>
+
+<h3 align="center">Go library for detecting and decoding various content front matter formats.</h3>
+
+<p align="center">
+    <a href="https://github.com/adrg/frontmatter/actions?query=workflow%3ACI">
+        <img alt="Build status" src="https://github.com/adrg/frontmatter/workflows/CI/badge.svg">
+    </a>
+    <a href="https://codecov.io/gh/adrg/frontmatter">
+        <img alt="Code coverage" src="https://codecov.io/gh/adrg/frontmatter/branch/master/graphs/badge.svg?branch=master">
+    </a>
+    <a href="https://pkg.go.dev/github.com/adrg/frontmatter">
+        <img alt="pkg.go.dev documentation" src="https://pkg.go.dev/badge/github.com/adrg/frontmatter">
+    </a>
+    <a href="https://opensource.org/licenses/MIT" rel="nofollow">
+        <img alt="MIT License" src="https://img.shields.io/github/license/adrg/frontmatter"/>
+    </a>
+    <a href="https://goreportcard.com/report/github.com/adrg/frontmatter">
+        <img alt="Go report card" src="https://goreportcard.com/badge/github.com/adrg/frontmatter?style=flat" />
+    </a>
+    <br />
+    <a href="https://github.com/adrg/frontmatter/graphs/contributors">
+        <img alt="GitHub contributors" src="https://img.shields.io/github/contributors/adrg/frontmatter" />
+    </a>
+    <a href="https://github.com/adrg/frontmatter/issues?q=is%3Aopen+is%3Aissue">
+        <img alt="GitHub open issues" src="https://img.shields.io/github/issues-raw/adrg/frontmatter">
+    </a>
+    <a href="https://github.com/adrg/frontmatter/issues?q=is%3Aissue+is%3Aclosed">
+        <img alt="GitHub closed issues" src="https://img.shields.io/github/issues-closed-raw/adrg/frontmatter" />
+    </a>
+    <a href="https://www.buymeacoffee.com/adrg">
+        <img alt="Buy me a coffee" src="https://img.shields.io/static/v1.svg?label=%20&message=Buy%20me%20a%20coffee&color=FF813F&logo=buy%20me%20a%20coffee&logoColor=white"/>
+    </a>
+    <a alt="Github stars" href="https://github.com/adrg/frontmatter/stargazers">
+        <img alt="GitHub stars" src="https://img.shields.io/github/stars/adrg/frontmatter?style=social">
+    </a>
+
+## Supported formats
+
+The following front matter formats are supported by default. If the default
+formats are not suitable for your use case, you can easily bring your own.
+For more information, see the [usage examples](#usage) below.
+
+![Default front matter formats](https://raw.githubusercontent.com/adrg/adrg.github.io/master/assets/projects/frontmatter/formats.png)
+
+## Installation
+
+```bash
+go get github.com/adrg/frontmatter
+```
+
+## Usage
+
+**Default usage.**
+
+```go
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/adrg/frontmatter"
+)
+
+var input = `
+---
+name: "frontmatter"
+tags: ["go", "yaml", "json", "toml"]
+---
+rest of the content`
+
+func main() {
+	var matter struct {
+		Name string   `yaml:"name"`
+		Tags []string `yaml:"tags"`
+	}
+
+	rest, err := frontmatter.Parse(strings.NewReader(input), &matter)
+	if err != nil {
+		// Treat error.
+	}
+	// NOTE: If a front matter must be present in the input data, use
+	//       frontmatter.MustParse instead.
+
+	fmt.Printf("%+v\n", matter)
+	fmt.Println(string(rest))
+
+	// Output:
+	// {Name:frontmatter Tags:[go yaml json toml]}
+	// rest of the content
+}
+```
+
+**Bring your own formats.**
+
+```go
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/adrg/frontmatter"
+	"gopkg.in/yaml.v2"
+)
+
+var input = `
+...
+name: "frontmatter"
+tags: ["go", "yaml", "json", "toml"]
+...
+rest of the content`
+
+func main() {
+	var matter struct {
+		Name string   `yaml:"name"`
+		Tags []string `yaml:"tags"`
+	}
+
+	formats := []*frontmatter.Format{
+		frontmatter.NewFormat("...", "...", yaml.Unmarshal),
+	}
+
+	rest, err := frontmatter.Parse(strings.NewReader(input), &matter, formats...)
+	if err != nil {
+		// Treat error.
+	}
+	// NOTE: If a front matter must be present in the input data, use
+	//       frontmatter.MustParse instead.
+
+	fmt.Printf("%+v\n", matter)
+	fmt.Println(string(rest))
+
+	// Output:
+	// {Name:frontmatter Tags:[go yaml json toml]}
+	// rest of the content
+}
+```
+
+Full documentation can be found at: https://pkg.go.dev/github.com/adrg/frontmatter.
+
+## Stargazers over time
+
+[![Stargazers over time](https://starchart.cc/adrg/frontmatter.svg)](https://starchart.cc/adrg/frontmatter)
+
+## Contributing
+
+Contributions in the form of pull requests, issues or just general feedback,
+are always welcome.
+See [CONTRIBUTING.MD](CONTRIBUTING.md).
+
+## Buy me a coffee
+
+If you found this project useful and want to support it, consider buying me a coffee.  
+<a href="https://www.buymeacoffee.com/adrg">
+    <img src="https://cdn.buymeacoffee.com/buttons/v2/arial-orange.png" alt="Buy Me A Coffee" height="42px">
+</a>
+
+## License
+
+Copyright (c) 2020 Adrian-George Bostan.
+
+This project is licensed under the [MIT license](https://opensource.org/licenses/MIT).
+See [LICENSE](LICENSE) for more details.

vendor/github.com/adrg/frontmatter/format.go

@@ -0,0 +1,70 @@
+package frontmatter
+
+import (
+	"encoding/json"
+
+	"github.com/BurntSushi/toml"
+	"gopkg.in/yaml.v2"
+)
+
+// UnmarshalFunc decodes the passed in `data` and stores it into
+// the value pointed to by `v`.
+type UnmarshalFunc func(data []byte, v interface{}) error
+
+// Format describes a front matter. It holds all the information
+// necessary in order to detect and decode a front matter format.
+type Format struct {
+	// Start defines the starting delimiter of the front matter.
+	// E.g.: `---` or `---yaml`.
+	Start string
+
+	// End defines the ending delimiter of the front matter.
+	// E.g.: `---`.
+	End string
+
+	// Unmarshal defines the unmarshal function used to decode
+	// the front matter data, after it has been detected.
+	// E.g.: json.Unmarshal (from the `encoding/json` package).
+	Unmarshal UnmarshalFunc
+
+	// UnmarshalDelims specifies whether the front matter
+	// delimiters are included in the data to be unmarshaled.
+	// Should be `false` in most cases.
+	UnmarshalDelims bool
+
+	// RequiresNewLine specifies whether a new (empty) line is
+	// required after the front matter.
+	// Should be `false` in most cases.
+	RequiresNewLine bool
+}
+
+// NewFormat returns a new front matter format.
+func NewFormat(start, end string, unmarshal UnmarshalFunc) *Format {
+	return newFormat(start, end, unmarshal, false, false)
+}
+
+func newFormat(start, end string, unmarshal UnmarshalFunc,
+	unmarshalDelims, requiresNewLine bool) *Format {
+	return &Format{
+		Start:           start,
+		End:             end,
+		Unmarshal:       unmarshal,
+		UnmarshalDelims: unmarshalDelims,
+		RequiresNewLine: requiresNewLine,
+	}
+}
+
+func defaultFormats() []*Format {
+	return []*Format{
+		// YAML.
+		newFormat("---", "---", yaml.Unmarshal, false, false),
+		newFormat("---yaml", "---", yaml.Unmarshal, false, false),
+		// TOML.
+		newFormat("+++", "+++", toml.Unmarshal, false, false),
+		newFormat("---toml", "---", toml.Unmarshal, false, false),
+		// JSON.
+		newFormat(";;;", ";;;", json.Unmarshal, false, false),
+		newFormat("---json", "---", json.Unmarshal, false, false),
+		newFormat("{", "}", json.Unmarshal, true, true),
+	}
+}

vendor/github.com/adrg/frontmatter/frontmatter.go

@@ -0,0 +1,47 @@
+/*
+Package frontmatter implements detection and decoding for various content
+front matter formats.
+
+  The following front matter formats are supported by default.
+
+  - YAML identified by:
+    • opening and closing `---` lines.
+    • opening `---yaml` and closing `---` lines.
+  - TOML identified by:
+    • opening and closing `+++` lines.
+    • opening `---toml` and closing `---` lines.
+  - JSON identified by:
+    • opening and closing `;;;` lines.
+    • opening `---json` and closing `---` lines.
+    • a single JSON object followed by an empty line.
+
+If the default formats are not suitable for your use case, you can easily bring
+your own. See the examples for more information.
+*/
+package frontmatter
+
+import (
+	"errors"
+	"io"
+)
+
+// ErrNotFound is reported by `MustParse` when a front matter is not found.
+var ErrNotFound = errors.New("not found")
+
+// Parse decodes the front matter from the specified reader into the value
+// pointed to by `v`, and returns the rest of the data. If a front matter
+// is not present, the original data is returned and `v` is left unchanged.
+// Front matters are detected and decoded based on the passed in `formats`.
+// If no formats are provided, the default formats are used.
+func Parse(r io.Reader, v interface{}, formats ...*Format) ([]byte, error) {
+	return newParser(r).parse(v, formats, false)
+}
+
+// MustParse decodes the front matter from the specified reader into the
+// value pointed to by `v`, and returns the rest of the data. If a front
+// matter is not present, `ErrNotFound` is reported.
+// Front matters are detected and decoded based on the passed in `formats`.
+// If no formats are provided, the default formats are used.
+func MustParse(r io.Reader, v interface{}, formats ...*Format) ([]byte, error) {
+	return newParser(r).parse(v, formats, true)
+}

vendor/github.com/adrg/frontmatter/parser.go

@@ -0,0 +1,132 @@
+package frontmatter
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+)
+
+type parser struct {
+	reader *bufio.Reader
+	output *bytes.Buffer
+
+	read  int
+	start int
+	end   int
+}
+
+func newParser(r io.Reader) *parser {
+	return &parser{
+		reader: bufio.NewReader(r),
+		output: bytes.NewBuffer(nil),
+	}
+}
+
+func (p *parser) parse(v interface{}, formats []*Format,
+	mustParse bool) ([]byte, error) {
+	// If no formats are provided, use the default ones.
+	if len(formats) == 0 {
+		formats = defaultFormats()
+	}
+
+	// Detect format.
+	f, err := p.detect(formats)
+	if err != nil {
+		return nil, err
+	}
+
+	// Extract front matter.
+	found := f != nil
+	if found {
+		if found, err = p.extract(f, v); err != nil {
+			return nil, err
+		}
+	}
+	if mustParse && !found {
+		return nil, ErrNotFound
+	}
+
+	// Read remaining data.
+	if _, err := p.output.ReadFrom(p.reader); err != nil {
+		return nil, err
+	}
+
+	return p.output.Bytes()[p.end:], nil
+}
+
+func (p *parser) detect(formats []*Format) (*Format, error) {
+	for {
+		read := p.read
+
+		line, atEOF, err := p.readLine()
+		if err != nil || atEOF {
+			return nil, err
+		}
+		if line == "" {
+			continue
+		}
+
+		for _, f := range formats {
+			if f.Start == line {
+				if !f.UnmarshalDelims {
+					read = p.read
+				}
+
+				p.start = read
+				return f, nil
+			}
+		}
+
+		return nil, nil
+	}
+}
+
+func (p *parser) extract(f *Format, v interface{}) (bool, error) {
+	for {
+		read := p.read
+
+		line, atEOF, err := p.readLine()
+		if err != nil {
+			return false, err
+		}
+
+	CheckLine:
+		if line != f.End {
+			if atEOF {
+				return false, err
+			}
+			continue
+		}
+		if f.RequiresNewLine {
+			if line, atEOF, err = p.readLine(); err != nil {
+				return false, err
+			}
+			if line != "" {
+				goto CheckLine
+			}
+		}
+		if f.UnmarshalDelims {
+			read = p.read
+		}
+
+		if err := f.Unmarshal(p.output.Bytes()[p.start:read], v); err != nil {
+			return false, err
+		}
+
+		p.end = p.read
+		return true, nil
+	}
+}
+
+func (p *parser) readLine() (string, bool, error) {
+	line, err := p.reader.ReadBytes('\n')
+
+	atEOF := err == io.EOF
+	if err != nil && !atEOF {
+		return "", false, err
+	}
+
+	p.read += len(line)
+	_, err = p.output.Write(line)
+	return string(bytes.TrimSpace(line)), atEOF, err
+}

vendor/github.com/google/go-cmp/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2017 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/google/go-cmp/cmp/compare.go

@@ -0,0 +1,671 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package cmp determines equality of values.
+//
+// This package is intended to be a more powerful and safer alternative to
+// [reflect.DeepEqual] for comparing whether two values are semantically equal.
+// It is intended to only be used in tests, as performance is not a goal and
+// it may panic if it cannot compare the values. Its propensity towards
+// panicking means that its unsuitable for production environments where a
+// spurious panic may be fatal.
+//
+// The primary features of cmp are:
+//
+//   - When the default behavior of equality does not suit the test's needs,
+//     custom equality functions can override the equality operation.
+//     For example, an equality function may report floats as equal so long as
+//     they are within some tolerance of each other.
+//
+//   - Types with an Equal method (e.g., [time.Time.Equal]) may use that method
+//     to determine equality. This allows package authors to determine
+//     the equality operation for the types that they define.
+//
+//   - If no custom equality functions are used and no Equal method is defined,
+//     equality is determined by recursively comparing the primitive kinds on
+//     both values, much like [reflect.DeepEqual]. Unlike [reflect.DeepEqual],
+//     unexported fields are not compared by default; they result in panics
+//     unless suppressed by using an [Ignore] option
+//     (see [github.com/google/go-cmp/cmp/cmpopts.IgnoreUnexported])
+//     or explicitly compared using the [Exporter] option.
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/diff"
+	"github.com/google/go-cmp/cmp/internal/function"
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+// TODO(≥go1.18): Use any instead of interface{}.
+
+// Equal reports whether x and y are equal by recursively applying the
+// following rules in the given order to x and y and all of their sub-values:
+//
+//   - Let S be the set of all [Ignore], [Transformer], and [Comparer] options that
+//     remain after applying all path filters, value filters, and type filters.
+//     If at least one [Ignore] exists in S, then the comparison is ignored.
+//     If the number of [Transformer] and [Comparer] options in S is non-zero,
+//     then Equal panics because it is ambiguous which option to use.
+//     If S contains a single [Transformer], then use that to transform
+//     the current values and recursively call Equal on the output values.
+//     If S contains a single [Comparer], then use that to compare the current values.
+//     Otherwise, evaluation proceeds to the next rule.
+//
+//   - If the values have an Equal method of the form "(T) Equal(T) bool" or
+//     "(T) Equal(I) bool" where T is assignable to I, then use the result of
+//     x.Equal(y) even if x or y is nil. Otherwise, no such method exists and
+//     evaluation proceeds to the next rule.
+//
+//   - Lastly, try to compare x and y based on their basic kinds.
+//     Simple kinds like booleans, integers, floats, complex numbers, strings,
+//     and channels are compared using the equivalent of the == operator in Go.
+//     Functions are only equal if they are both nil, otherwise they are unequal.
+//
+// Structs are equal if recursively calling Equal on all fields report equal.
+// If a struct contains unexported fields, Equal panics unless an [Ignore] option
+// (e.g., [github.com/google/go-cmp/cmp/cmpopts.IgnoreUnexported]) ignores that field
+// or the [Exporter] option explicitly permits comparing the unexported field.
+//
+// Slices are equal if they are both nil or both non-nil, where recursively
+// calling Equal on all non-ignored slice or array elements report equal.
+// Empty non-nil slices and nil slices are not equal; to equate empty slices,
+// consider using [github.com/google/go-cmp/cmp/cmpopts.EquateEmpty].
+//
+// Maps are equal if they are both nil or both non-nil, where recursively
+// calling Equal on all non-ignored map entries report equal.
+// Map keys are equal according to the == operator.
+// To use custom comparisons for map keys, consider using
+// [github.com/google/go-cmp/cmp/cmpopts.SortMaps].
+// Empty non-nil maps and nil maps are not equal; to equate empty maps,
+// consider using [github.com/google/go-cmp/cmp/cmpopts.EquateEmpty].
+//
+// Pointers and interfaces are equal if they are both nil or both non-nil,
+// where they have the same underlying concrete type and recursively
+// calling Equal on the underlying values reports equal.
+//
+// Before recursing into a pointer, slice element, or map, the current path
+// is checked to detect whether the address has already been visited.
+// If there is a cycle, then the pointed at values are considered equal
+// only if both addresses were previously visited in the same path step.
+func Equal(x, y interface{}, opts ...Option) bool {
+	s := newState(opts)
+	s.compareAny(rootStep(x, y))
+	return s.result.Equal()
+}
+
+// Diff returns a human-readable report of the differences between two values:
+// y - x. It returns an empty string if and only if Equal returns true for the
+// same input values and options.
+//
+// The output is displayed as a literal in pseudo-Go syntax.
+// At the start of each line, a "-" prefix indicates an element removed from x,
+// a "+" prefix to indicates an element added from y, and the lack of a prefix
+// indicates an element common to both x and y. If possible, the output
+// uses fmt.Stringer.String or error.Error methods to produce more humanly
+// readable outputs. In such cases, the string is prefixed with either an
+// 's' or 'e' character, respectively, to indicate that the method was called.
+//
+// Do not depend on this output being stable. If you need the ability to
+// programmatically interpret the difference, consider using a custom Reporter.
+func Diff(x, y interface{}, opts ...Option) string {
+	s := newState(opts)
+
+	// Optimization: If there are no other reporters, we can optimize for the
+	// common case where the result is equal (and thus no reported difference).
+	// This avoids the expensive construction of a difference tree.
+	if len(s.reporters) == 0 {
+		s.compareAny(rootStep(x, y))
+		if s.result.Equal() {
+			return ""
+		}
+		s.result = diff.Result{} // Reset results
+	}
+
+	r := new(defaultReporter)
+	s.reporters = append(s.reporters, reporter{r})
+	s.compareAny(rootStep(x, y))
+	d := r.String()
+	if (d == "") != s.result.Equal() {
+		panic("inconsistent difference and equality results")
+	}
+	return d
+}
+
+// rootStep constructs the first path step. If x and y have differing types,
+// then they are stored within an empty interface type.
+func rootStep(x, y interface{}) PathStep {
+	vx := reflect.ValueOf(x)
+	vy := reflect.ValueOf(y)
+
+	// If the inputs are different types, auto-wrap them in an empty interface
+	// so that they have the same parent type.
+	var t reflect.Type
+	if !vx.IsValid() || !vy.IsValid() || vx.Type() != vy.Type() {
+		t = anyType
+		if vx.IsValid() {
+			vvx := reflect.New(t).Elem()
+			vvx.Set(vx)
+			vx = vvx
+		}
+		if vy.IsValid() {
+			vvy := reflect.New(t).Elem()
+			vvy.Set(vy)
+			vy = vvy
+		}
+	} else {
+		t = vx.Type()
+	}
+
+	return &pathStep{t, vx, vy}
+}
+
+type state struct {
+	// These fields represent the "comparison state".
+	// Calling statelessCompare must not result in observable changes to these.
+	result    diff.Result // The current result of comparison
+	curPath   Path        // The current path in the value tree
+	curPtrs   pointerPath // The current set of visited pointers
+	reporters []reporter  // Optional reporters
+
+	// recChecker checks for infinite cycles applying the same set of
+	// transformers upon the output of itself.
+	recChecker recChecker
+
+	// dynChecker triggers pseudo-random checks for option correctness.
+	// It is safe for statelessCompare to mutate this value.
+	dynChecker dynChecker
+
+	// These fields, once set by processOption, will not change.
+	exporters []exporter // List of exporters for structs with unexported fields
+	opts      Options    // List of all fundamental and filter options
+}
+
+func newState(opts []Option) *state {
+	// Always ensure a validator option exists to validate the inputs.
+	s := &state{opts: Options{validator{}}}
+	s.curPtrs.Init()
+	s.processOption(Options(opts))
+	return s
+}
+
+func (s *state) processOption(opt Option) {
+	switch opt := opt.(type) {
+	case nil:
+	case Options:
+		for _, o := range opt {
+			s.processOption(o)
+		}
+	case coreOption:
+		type filtered interface {
+			isFiltered() bool
+		}
+		if fopt, ok := opt.(filtered); ok && !fopt.isFiltered() {
+			panic(fmt.Sprintf("cannot use an unfiltered option: %v", opt))
+		}
+		s.opts = append(s.opts, opt)
+	case exporter:
+		s.exporters = append(s.exporters, opt)
+	case reporter:
+		s.reporters = append(s.reporters, opt)
+	default:
+		panic(fmt.Sprintf("unknown option %T", opt))
+	}
+}
+
+// statelessCompare compares two values and returns the result.
+// This function is stateless in that it does not alter the current result,
+// or output to any registered reporters.
+func (s *state) statelessCompare(step PathStep) diff.Result {
+	// We do not save and restore curPath and curPtrs because all of the
+	// compareX methods should properly push and pop from them.
+	// It is an implementation bug if the contents of the paths differ from
+	// when calling this function to when returning from it.
+
+	oldResult, oldReporters := s.result, s.reporters
+	s.result = diff.Result{} // Reset result
+	s.reporters = nil        // Remove reporters to avoid spurious printouts
+	s.compareAny(step)
+	res := s.result
+	s.result, s.reporters = oldResult, oldReporters
+	return res
+}
+
+func (s *state) compareAny(step PathStep) {
+	// Update the path stack.
+	s.curPath.push(step)
+	defer s.curPath.pop()
+	for _, r := range s.reporters {
+		r.PushStep(step)
+		defer r.PopStep()
+	}
+	s.recChecker.Check(s.curPath)
+
+	// Cycle-detection for slice elements (see NOTE in compareSlice).
+	t := step.Type()
+	vx, vy := step.Values()
+	if si, ok := step.(SliceIndex); ok && si.isSlice && vx.IsValid() && vy.IsValid() {
+		px, py := vx.Addr(), vy.Addr()
+		if eq, visited := s.curPtrs.Push(px, py); visited {
+			s.report(eq, reportByCycle)
+			return
+		}
+		defer s.curPtrs.Pop(px, py)
+	}
+
+	// Rule 1: Check whether an option applies on this node in the value tree.
+	if s.tryOptions(t, vx, vy) {
+		return
+	}
+
+	// Rule 2: Check whether the type has a valid Equal method.
+	if s.tryMethod(t, vx, vy) {
+		return
+	}
+
+	// Rule 3: Compare based on the underlying kind.
+	switch t.Kind() {
+	case reflect.Bool:
+		s.report(vx.Bool() == vy.Bool(), 0)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		s.report(vx.Int() == vy.Int(), 0)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		s.report(vx.Uint() == vy.Uint(), 0)
+	case reflect.Float32, reflect.Float64:
+		s.report(vx.Float() == vy.Float(), 0)
+	case reflect.Complex64, reflect.Complex128:
+		s.report(vx.Complex() == vy.Complex(), 0)
+	case reflect.String:
+		s.report(vx.String() == vy.String(), 0)
+	case reflect.Chan, reflect.UnsafePointer:
+		s.report(vx.Pointer() == vy.Pointer(), 0)
+	case reflect.Func:
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+	case reflect.Struct:
+		s.compareStruct(t, vx, vy)
+	case reflect.Slice, reflect.Array:
+		s.compareSlice(t, vx, vy)
+	case reflect.Map:
+		s.compareMap(t, vx, vy)
+	case reflect.Ptr:
+		s.comparePtr(t, vx, vy)
+	case reflect.Interface:
+		s.compareInterface(t, vx, vy)
+	default:
+		panic(fmt.Sprintf("%v kind not handled", t.Kind()))
+	}
+}
+
+func (s *state) tryOptions(t reflect.Type, vx, vy reflect.Value) bool {
+	// Evaluate all filters and apply the remaining options.
+	if opt := s.opts.filter(s, t, vx, vy); opt != nil {
+		opt.apply(s, vx, vy)
+		return true
+	}
+	return false
+}
+
+func (s *state) tryMethod(t reflect.Type, vx, vy reflect.Value) bool {
+	// Check if this type even has an Equal method.
+	m, ok := t.MethodByName("Equal")
+	if !ok || !function.IsType(m.Type, function.EqualAssignable) {
+		return false
+	}
+
+	eq := s.callTTBFunc(m.Func, vx, vy)
+	s.report(eq, reportByMethod)
+	return true
+}
+
+func (s *state) callTRFunc(f, v reflect.Value, step Transform) reflect.Value {
+	if !s.dynChecker.Next() {
+		return f.Call([]reflect.Value{v})[0]
+	}
+
+	// Run the function twice and ensure that we get the same results back.
+	// We run in goroutines so that the race detector (if enabled) can detect
+	// unsafe mutations to the input.
+	c := make(chan reflect.Value)
+	go detectRaces(c, f, v)
+	got := <-c
+	want := f.Call([]reflect.Value{v})[0]
+	if step.vx, step.vy = got, want; !s.statelessCompare(step).Equal() {
+		// To avoid false-positives with non-reflexive equality operations,
+		// we sanity check whether a value is equal to itself.
+		if step.vx, step.vy = want, want; !s.statelessCompare(step).Equal() {
+			return want
+		}
+		panic(fmt.Sprintf("non-deterministic function detected: %s", function.NameOf(f)))
+	}
+	return want
+}
+
+func (s *state) callTTBFunc(f, x, y reflect.Value) bool {
+	if !s.dynChecker.Next() {
+		return f.Call([]reflect.Value{x, y})[0].Bool()
+	}
+
+	// Swapping the input arguments is sufficient to check that
+	// f is symmetric and deterministic.
+	// We run in goroutines so that the race detector (if enabled) can detect
+	// unsafe mutations to the input.
+	c := make(chan reflect.Value)
+	go detectRaces(c, f, y, x)
+	got := <-c
+	want := f.Call([]reflect.Value{x, y})[0].Bool()
+	if !got.IsValid() || got.Bool() != want {
+		panic(fmt.Sprintf("non-deterministic or non-symmetric function detected: %s", function.NameOf(f)))
+	}
+	return want
+}
+
+func detectRaces(c chan<- reflect.Value, f reflect.Value, vs ...reflect.Value) {
+	var ret reflect.Value
+	defer func() {
+		recover() // Ignore panics, let the other call to f panic instead
+		c <- ret
+	}()
+	ret = f.Call(vs)[0]
+}
+
+func (s *state) compareStruct(t reflect.Type, vx, vy reflect.Value) {
+	var addr bool
+	var vax, vay reflect.Value // Addressable versions of vx and vy
+
+	var mayForce, mayForceInit bool
+	step := StructField{&structField{}}
+	for i := 0; i < t.NumField(); i++ {
+		step.typ = t.Field(i).Type
+		step.vx = vx.Field(i)
+		step.vy = vy.Field(i)
+		step.name = t.Field(i).Name
+		step.idx = i
+		step.unexported = !isExported(step.name)
+		if step.unexported {
+			if step.name == "_" {
+				continue
+			}
+			// Defer checking of unexported fields until later to give an
+			// Ignore a chance to ignore the field.
+			if !vax.IsValid() || !vay.IsValid() {
+				// For retrieveUnexportedField to work, the parent struct must
+				// be addressable. Create a new copy of the values if
+				// necessary to make them addressable.
+				addr = vx.CanAddr() || vy.CanAddr()
+				vax = makeAddressable(vx)
+				vay = makeAddressable(vy)
+			}
+			if !mayForceInit {
+				for _, xf := range s.exporters {
+					mayForce = mayForce || xf(t)
+				}
+				mayForceInit = true
+			}
+			step.mayForce = mayForce
+			step.paddr = addr
+			step.pvx = vax
+			step.pvy = vay
+			step.field = t.Field(i)
+		}
+		s.compareAny(step)
+	}
+}
+
+func (s *state) compareSlice(t reflect.Type, vx, vy reflect.Value) {
+	isSlice := t.Kind() == reflect.Slice
+	if isSlice && (vx.IsNil() || vy.IsNil()) {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// NOTE: It is incorrect to call curPtrs.Push on the slice header pointer
+	// since slices represents a list of pointers, rather than a single pointer.
+	// The pointer checking logic must be handled on a per-element basis
+	// in compareAny.
+	//
+	// A slice header (see reflect.SliceHeader) in Go is a tuple of a starting
+	// pointer P, a length N, and a capacity C. Supposing each slice element has
+	// a memory size of M, then the slice is equivalent to the list of pointers:
+	//	[P+i*M for i in range(N)]
+	//
+	// For example, v[:0] and v[:1] are slices with the same starting pointer,
+	// but they are clearly different values. Using the slice pointer alone
+	// violates the assumption that equal pointers implies equal values.
+
+	step := SliceIndex{&sliceIndex{pathStep: pathStep{typ: t.Elem()}, isSlice: isSlice}}
+	withIndexes := func(ix, iy int) SliceIndex {
+		if ix >= 0 {
+			step.vx, step.xkey = vx.Index(ix), ix
+		} else {
+			step.vx, step.xkey = reflect.Value{}, -1
+		}
+		if iy >= 0 {
+			step.vy, step.ykey = vy.Index(iy), iy
+		} else {
+			step.vy, step.ykey = reflect.Value{}, -1
+		}
+		return step
+	}
+
+	// Ignore options are able to ignore missing elements in a slice.
+	// However, detecting these reliably requires an optimal differencing
+	// algorithm, for which diff.Difference is not.
+	//
+	// Instead, we first iterate through both slices to detect which elements
+	// would be ignored if standing alone. The index of non-discarded elements
+	// are stored in a separate slice, which diffing is then performed on.
+	var indexesX, indexesY []int
+	var ignoredX, ignoredY []bool
+	for ix := 0; ix < vx.Len(); ix++ {
+		ignored := s.statelessCompare(withIndexes(ix, -1)).NumDiff == 0
+		if !ignored {
+			indexesX = append(indexesX, ix)
+		}
+		ignoredX = append(ignoredX, ignored)
+	}
+	for iy := 0; iy < vy.Len(); iy++ {
+		ignored := s.statelessCompare(withIndexes(-1, iy)).NumDiff == 0
+		if !ignored {
+			indexesY = append(indexesY, iy)
+		}
+		ignoredY = append(ignoredY, ignored)
+	}
+
+	// Compute an edit-script for slices vx and vy (excluding ignored elements).
+	edits := diff.Difference(len(indexesX), len(indexesY), func(ix, iy int) diff.Result {
+		return s.statelessCompare(withIndexes(indexesX[ix], indexesY[iy]))
+	})
+
+	// Replay the ignore-scripts and the edit-script.
+	var ix, iy int
+	for ix < vx.Len() || iy < vy.Len() {
+		var e diff.EditType
+		switch {
+		case ix < len(ignoredX) && ignoredX[ix]:
+			e = diff.UniqueX
+		case iy < len(ignoredY) && ignoredY[iy]:
+			e = diff.UniqueY
+		default:
+			e, edits = edits[0], edits[1:]
+		}
+		switch e {
+		case diff.UniqueX:
+			s.compareAny(withIndexes(ix, -1))
+			ix++
+		case diff.UniqueY:
+			s.compareAny(withIndexes(-1, iy))
+			iy++
+		default:
+			s.compareAny(withIndexes(ix, iy))
+			ix++
+			iy++
+		}
+	}
+}
+
+func (s *state) compareMap(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// Cycle-detection for maps.
+	if eq, visited := s.curPtrs.Push(vx, vy); visited {
+		s.report(eq, reportByCycle)
+		return
+	}
+	defer s.curPtrs.Pop(vx, vy)
+
+	// We combine and sort the two map keys so that we can perform the
+	// comparisons in a deterministic order.
+	step := MapIndex{&mapIndex{pathStep: pathStep{typ: t.Elem()}}}
+	for _, k := range value.SortKeys(append(vx.MapKeys(), vy.MapKeys()...)) {
+		step.vx = vx.MapIndex(k)
+		step.vy = vy.MapIndex(k)
+		step.key = k
+		if !step.vx.IsValid() && !step.vy.IsValid() {
+			// It is possible for both vx and vy to be invalid if the
+			// key contained a NaN value in it.
+			//
+			// Even with the ability to retrieve NaN keys in Go 1.12,
+			// there still isn't a sensible way to compare the values since
+			// a NaN key may map to multiple unordered values.
+			// The most reasonable way to compare NaNs would be to compare the
+			// set of values. However, this is impossible to do efficiently
+			// since set equality is provably an O(n^2) operation given only
+			// an Equal function. If we had a Less function or Hash function,
+			// this could be done in O(n*log(n)) or O(n), respectively.
+			//
+			// Rather than adding complex logic to deal with NaNs, make it
+			// the user's responsibility to compare such obscure maps.
+			const help = "consider providing a Comparer to compare the map"
+			panic(fmt.Sprintf("%#v has map key with NaNs\n%s", s.curPath, help))
+		}
+		s.compareAny(step)
+	}
+}
+
+func (s *state) comparePtr(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+
+	// Cycle-detection for pointers.
+	if eq, visited := s.curPtrs.Push(vx, vy); visited {
+		s.report(eq, reportByCycle)
+		return
+	}
+	defer s.curPtrs.Pop(vx, vy)
+
+	vx, vy = vx.Elem(), vy.Elem()
+	s.compareAny(Indirect{&indirect{pathStep{t.Elem(), vx, vy}}})
+}
+
+func (s *state) compareInterface(t reflect.Type, vx, vy reflect.Value) {
+	if vx.IsNil() || vy.IsNil() {
+		s.report(vx.IsNil() && vy.IsNil(), 0)
+		return
+	}
+	vx, vy = vx.Elem(), vy.Elem()
+	if vx.Type() != vy.Type() {
+		s.report(false, 0)
+		return
+	}
+	s.compareAny(TypeAssertion{&typeAssertion{pathStep{vx.Type(), vx, vy}}})
+}
+
+func (s *state) report(eq bool, rf resultFlags) {
+	if rf&reportByIgnore == 0 {
+		if eq {
+			s.result.NumSame++
+			rf |= reportEqual
+		} else {
+			s.result.NumDiff++
+			rf |= reportUnequal
+		}
+	}
+	for _, r := range s.reporters {
+		r.Report(Result{flags: rf})
+	}
+}
+
+// recChecker tracks the state needed to periodically perform checks that
+// user provided transformers are not stuck in an infinitely recursive cycle.
+type recChecker struct{ next int }
+
+// Check scans the Path for any recursive transformers and panics when any
+// recursive transformers are detected. Note that the presence of a
+// recursive Transformer does not necessarily imply an infinite cycle.
+// As such, this check only activates after some minimal number of path steps.
+func (rc *recChecker) Check(p Path) {
+	const minLen = 1 << 16
+	if rc.next == 0 {
+		rc.next = minLen
+	}
+	if len(p) < rc.next {
+		return
+	}
+	rc.next <<= 1
+
+	// Check whether the same transformer has appeared at least twice.
+	var ss []string
+	m := map[Option]int{}
+	for _, ps := range p {
+		if t, ok := ps.(Transform); ok {
+			t := t.Option()
+			if m[t] == 1 { // Transformer was used exactly once before
+				tf := t.(*transformer).fnc.Type()
+				ss = append(ss, fmt.Sprintf("%v: %v => %v", t, tf.In(0), tf.Out(0)))
+			}
+			m[t]++
+		}
+	}
+	if len(ss) > 0 {
+		const warning = "recursive set of Transformers detected"
+		const help = "consider using cmpopts.AcyclicTransformer"
+		set := strings.Join(ss, "\n\t")
+		panic(fmt.Sprintf("%s:\n\t%s\n%s", warning, set, help))
+	}
+}
+
+// dynChecker tracks the state needed to periodically perform checks that
+// user provided functions are symmetric and deterministic.
+// The zero value is safe for immediate use.
+type dynChecker struct{ curr, next int }
+
+// Next increments the state and reports whether a check should be performed.
+//
+// Checks occur every Nth function call, where N is a triangular number:
+//
+//	0 1 3 6 10 15 21 28 36 45 55 66 78 91 105 120 136 153 171 190 ...
+//
+// See https://en.wikipedia.org/wiki/Triangular_number
+//
+// This sequence ensures that the cost of checks drops significantly as
+// the number of functions calls grows larger.
+func (dc *dynChecker) Next() bool {
+	ok := dc.curr == dc.next
+	if ok {
+		dc.curr = 0
+		dc.next++
+	}
+	dc.curr++
+	return ok
+}
+
+// makeAddressable returns a value that is always addressable.
+// It returns the input verbatim if it is already addressable,
+// otherwise it creates a new value and returns an addressable copy.
+func makeAddressable(v reflect.Value) reflect.Value {
+	if v.CanAddr() {
+		return v
+	}
+	vc := reflect.New(v.Type()).Elem()
+	vc.Set(v)
+	return vc
+}

vendor/github.com/google/go-cmp/cmp/export.go

@@ -0,0 +1,31 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// retrieveUnexportedField uses unsafe to forcibly retrieve any field from
+// a struct such that the value has read-write permissions.
+//
+// The parent struct, v, must be addressable, while f must be a StructField
+// describing the field to retrieve. If addr is false,
+// then the returned value will be shallowed copied to be non-addressable.
+func retrieveUnexportedField(v reflect.Value, f reflect.StructField, addr bool) reflect.Value {
+	ve := reflect.NewAt(f.Type, unsafe.Pointer(uintptr(unsafe.Pointer(v.UnsafeAddr()))+f.Offset)).Elem()
+	if !addr {
+		// A field is addressable if and only if the struct is addressable.
+		// If the original parent value was not addressable, shallow copy the
+		// value to make it non-addressable to avoid leaking an implementation
+		// detail of how forcibly exporting a field works.
+		if ve.Kind() == reflect.Interface && ve.IsNil() {
+			return reflect.Zero(f.Type)
+		}
+		return reflect.ValueOf(ve.Interface()).Convert(f.Type)
+	}
+	return ve
+}

vendor/github.com/google/go-cmp/cmp/internal/diff/debug_disable.go

@@ -0,0 +1,18 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !cmp_debug
+// +build !cmp_debug
+
+package diff
+
+var debug debugger
+
+type debugger struct{}
+
+func (debugger) Begin(_, _ int, f EqualFunc, _, _ *EditScript) EqualFunc {
+	return f
+}
+func (debugger) Update() {}
+func (debugger) Finish() {}

vendor/github.com/google/go-cmp/cmp/internal/diff/debug_enable.go

@@ -0,0 +1,123 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build cmp_debug
+// +build cmp_debug
+
+package diff
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+)
+
+// The algorithm can be seen running in real-time by enabling debugging:
+//	go test -tags=cmp_debug -v
+//
+// Example output:
+//	=== RUN   TestDifference/#34
+//	┌───────────────────────────────┐
+//	│ \ · · · · · · · · · · · · · · │
+//	│ · # · · · · · · · · · · · · · │
+//	│ · \ · · · · · · · · · · · · · │
+//	│ · · \ · · · · · · · · · · · · │
+//	│ · · · X # · · · · · · · · · · │
+//	│ · · · # \ · · · · · · · · · · │
+//	│ · · · · · # # · · · · · · · · │
+//	│ · · · · · # \ · · · · · · · · │
+//	│ · · · · · · · \ · · · · · · · │
+//	│ · · · · · · · · \ · · · · · · │
+//	│ · · · · · · · · · \ · · · · · │
+//	│ · · · · · · · · · · \ · · # · │
+//	│ · · · · · · · · · · · \ # # · │
+//	│ · · · · · · · · · · · # # # · │
+//	│ · · · · · · · · · · # # # # · │
+//	│ · · · · · · · · · # # # # # · │
+//	│ · · · · · · · · · · · · · · \ │
+//	└───────────────────────────────┘
+//	[.Y..M.XY......YXYXY.|]
+//
+// The grid represents the edit-graph where the horizontal axis represents
+// list X and the vertical axis represents list Y. The start of the two lists
+// is the top-left, while the ends are the bottom-right. The '·' represents
+// an unexplored node in the graph. The '\' indicates that the two symbols
+// from list X and Y are equal. The 'X' indicates that two symbols are similar
+// (but not exactly equal) to each other. The '#' indicates that the two symbols
+// are different (and not similar). The algorithm traverses this graph trying to
+// make the paths starting in the top-left and the bottom-right connect.
+//
+// The series of '.', 'X', 'Y', and 'M' characters at the bottom represents
+// the currently established path from the forward and reverse searches,
+// separated by a '|' character.
+
+const (
+	updateDelay  = 100 * time.Millisecond
+	finishDelay  = 500 * time.Millisecond
+	ansiTerminal = true // ANSI escape codes used to move terminal cursor
+)
+
+var debug debugger
+
+type debugger struct {
+	sync.Mutex
+	p1, p2           EditScript
+	fwdPath, revPath *EditScript
+	grid             []byte
+	lines            int
+}
+
+func (dbg *debugger) Begin(nx, ny int, f EqualFunc, p1, p2 *EditScript) EqualFunc {
+	dbg.Lock()
+	dbg.fwdPath, dbg.revPath = p1, p2
+	top := "┌─" + strings.Repeat("──", nx) + "┐\n"
+	row := "│ " + strings.Repeat("· ", nx) + "│\n"
+	btm := "└─" + strings.Repeat("──", nx) + "┘\n"
+	dbg.grid = []byte(top + strings.Repeat(row, ny) + btm)
+	dbg.lines = strings.Count(dbg.String(), "\n")
+	fmt.Print(dbg)
+
+	// Wrap the EqualFunc so that we can intercept each result.
+	return func(ix, iy int) (r Result) {
+		cell := dbg.grid[len(top)+iy*len(row):][len("│ ")+len("· ")*ix:][:len("·")]
+		for i := range cell {
+			cell[i] = 0 // Zero out the multiple bytes of UTF-8 middle-dot
+		}
+		switch r = f(ix, iy); {
+		case r.Equal():
+			cell[0] = '\\'
+		case r.Similar():
+			cell[0] = 'X'
+		default:
+			cell[0] = '#'
+		}
+		return
+	}
+}
+
+func (dbg *debugger) Update() {
+	dbg.print(updateDelay)
+}
+
+func (dbg *debugger) Finish() {
+	dbg.print(finishDelay)
+	dbg.Unlock()
+}
+
+func (dbg *debugger) String() string {
+	dbg.p1, dbg.p2 = *dbg.fwdPath, dbg.p2[:0]
+	for i := len(*dbg.revPath) - 1; i >= 0; i-- {
+		dbg.p2 = append(dbg.p2, (*dbg.revPath)[i])
+	}
+	return fmt.Sprintf("%s[%v|%v]\n\n", dbg.grid, dbg.p1, dbg.p2)
+}
+
+func (dbg *debugger) print(d time.Duration) {
+	if ansiTerminal {
+		fmt.Printf("\x1b[%dA", dbg.lines) // Reset terminal cursor
+	}
+	fmt.Print(dbg)
+	time.Sleep(d)
+}

vendor/github.com/google/go-cmp/cmp/internal/diff/diff.go

@@ -0,0 +1,402 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package diff implements an algorithm for producing edit-scripts.
+// The edit-script is a sequence of operations needed to transform one list
+// of symbols into another (or vice-versa). The edits allowed are insertions,
+// deletions, and modifications. The summation of all edits is called the
+// Levenshtein distance as this problem is well-known in computer science.
+//
+// This package prioritizes performance over accuracy. That is, the run time
+// is more important than obtaining a minimal Levenshtein distance.
+package diff
+
+import (
+	"math/rand"
+	"time"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+)
+
+// EditType represents a single operation within an edit-script.
+type EditType uint8
+
+const (
+	// Identity indicates that a symbol pair is identical in both list X and Y.
+	Identity EditType = iota
+	// UniqueX indicates that a symbol only exists in X and not Y.
+	UniqueX
+	// UniqueY indicates that a symbol only exists in Y and not X.
+	UniqueY
+	// Modified indicates that a symbol pair is a modification of each other.
+	Modified
+)
+
+// EditScript represents the series of differences between two lists.
+type EditScript []EditType
+
+// String returns a human-readable string representing the edit-script where
+// Identity, UniqueX, UniqueY, and Modified are represented by the
+// '.', 'X', 'Y', and 'M' characters, respectively.
+func (es EditScript) String() string {
+	b := make([]byte, len(es))
+	for i, e := range es {
+		switch e {
+		case Identity:
+			b[i] = '.'
+		case UniqueX:
+			b[i] = 'X'
+		case UniqueY:
+			b[i] = 'Y'
+		case Modified:
+			b[i] = 'M'
+		default:
+			panic("invalid edit-type")
+		}
+	}
+	return string(b)
+}
+
+// stats returns a histogram of the number of each type of edit operation.
+func (es EditScript) stats() (s struct{ NI, NX, NY, NM int }) {
+	for _, e := range es {
+		switch e {
+		case Identity:
+			s.NI++
+		case UniqueX:
+			s.NX++
+		case UniqueY:
+			s.NY++
+		case Modified:
+			s.NM++
+		default:
+			panic("invalid edit-type")
+		}
+	}
+	return
+}
+
+// Dist is the Levenshtein distance and is guaranteed to be 0 if and only if
+// lists X and Y are equal.
+func (es EditScript) Dist() int { return len(es) - es.stats().NI }
+
+// LenX is the length of the X list.
+func (es EditScript) LenX() int { return len(es) - es.stats().NY }
+
+// LenY is the length of the Y list.
+func (es EditScript) LenY() int { return len(es) - es.stats().NX }
+
+// EqualFunc reports whether the symbols at indexes ix and iy are equal.
+// When called by Difference, the index is guaranteed to be within nx and ny.
+type EqualFunc func(ix int, iy int) Result
+
+// Result is the result of comparison.
+// NumSame is the number of sub-elements that are equal.
+// NumDiff is the number of sub-elements that are not equal.
+type Result struct{ NumSame, NumDiff int }
+
+// BoolResult returns a Result that is either Equal or not Equal.
+func BoolResult(b bool) Result {
+	if b {
+		return Result{NumSame: 1} // Equal, Similar
+	} else {
+		return Result{NumDiff: 2} // Not Equal, not Similar
+	}
+}
+
+// Equal indicates whether the symbols are equal. Two symbols are equal
+// if and only if NumDiff == 0. If Equal, then they are also Similar.
+func (r Result) Equal() bool { return r.NumDiff == 0 }
+
+// Similar indicates whether two symbols are similar and may be represented
+// by using the Modified type. As a special case, we consider binary comparisons
+// (i.e., those that return Result{1, 0} or Result{0, 1}) to be similar.
+//
+// The exact ratio of NumSame to NumDiff to determine similarity may change.
+func (r Result) Similar() bool {
+	// Use NumSame+1 to offset NumSame so that binary comparisons are similar.
+	return r.NumSame+1 >= r.NumDiff
+}
+
+var randBool = rand.New(rand.NewSource(time.Now().Unix())).Intn(2) == 0
+
+// Difference reports whether two lists of lengths nx and ny are equal
+// given the definition of equality provided as f.
+//
+// This function returns an edit-script, which is a sequence of operations
+// needed to convert one list into the other. The following invariants for
+// the edit-script are maintained:
+//   - eq == (es.Dist()==0)
+//   - nx == es.LenX()
+//   - ny == es.LenY()
+//
+// This algorithm is not guaranteed to be an optimal solution (i.e., one that
+// produces an edit-script with a minimal Levenshtein distance). This algorithm
+// favors performance over optimality. The exact output is not guaranteed to
+// be stable and may change over time.
+func Difference(nx, ny int, f EqualFunc) (es EditScript) {
+	// This algorithm is based on traversing what is known as an "edit-graph".
+	// See Figure 1 from "An O(ND) Difference Algorithm and Its Variations"
+	// by Eugene W. Myers. Since D can be as large as N itself, this is
+	// effectively O(N^2). Unlike the algorithm from that paper, we are not
+	// interested in the optimal path, but at least some "decent" path.
+	//
+	// For example, let X and Y be lists of symbols:
+	//	X = [A B C A B B A]
+	//	Y = [C B A B A C]
+	//
+	// The edit-graph can be drawn as the following:
+	//	   A B C A B B A
+	//	  ┌─────────────┐
+	//	C │_|_|\|_|_|_|_│ 0
+	//	B │_|\|_|_|\|\|_│ 1
+	//	A │\|_|_|\|_|_|\│ 2
+	//	B │_|\|_|_|\|\|_│ 3
+	//	A │\|_|_|\|_|_|\│ 4
+	//	C │ | |\| | | | │ 5
+	//	  └─────────────┘ 6
+	//	   0 1 2 3 4 5 6 7
+	//
+	// List X is written along the horizontal axis, while list Y is written
+	// along the vertical axis. At any point on this grid, if the symbol in
+	// list X matches the corresponding symbol in list Y, then a '\' is drawn.
+	// The goal of any minimal edit-script algorithm is to find a path from the
+	// top-left corner to the bottom-right corner, while traveling through the
+	// fewest horizontal or vertical edges.
+	// A horizontal edge is equivalent to inserting a symbol from list X.
+	// A vertical edge is equivalent to inserting a symbol from list Y.
+	// A diagonal edge is equivalent to a matching symbol between both X and Y.
+
+	// Invariants:
+	//   - 0 ≤ fwdPath.X ≤ (fwdFrontier.X, revFrontier.X) ≤ revPath.X ≤ nx
+	//   - 0 ≤ fwdPath.Y ≤ (fwdFrontier.Y, revFrontier.Y) ≤ revPath.Y ≤ ny
+	//
+	// In general:
+	//   - fwdFrontier.X < revFrontier.X
+	//   - fwdFrontier.Y < revFrontier.Y
+	//
+	// Unless, it is time for the algorithm to terminate.
+	fwdPath := path{+1, point{0, 0}, make(EditScript, 0, (nx+ny)/2)}
+	revPath := path{-1, point{nx, ny}, make(EditScript, 0)}
+	fwdFrontier := fwdPath.point // Forward search frontier
+	revFrontier := revPath.point // Reverse search frontier
+
+	// Search budget bounds the cost of searching for better paths.
+	// The longest sequence of non-matching symbols that can be tolerated is
+	// approximately the square-root of the search budget.
+	searchBudget := 4 * (nx + ny) // O(n)
+
+	// Running the tests with the "cmp_debug" build tag prints a visualization
+	// of the algorithm running in real-time. This is educational for
+	// understanding how the algorithm works. See debug_enable.go.
+	f = debug.Begin(nx, ny, f, &fwdPath.es, &revPath.es)
+
+	// The algorithm below is a greedy, meet-in-the-middle algorithm for
+	// computing sub-optimal edit-scripts between two lists.
+	//
+	// The algorithm is approximately as follows:
+	//   - Searching for differences switches back-and-forth between
+	//     a search that starts at the beginning (the top-left corner), and
+	//     a search that starts at the end (the bottom-right corner).
+	//     The goal of the search is connect with the search
+	//     from the opposite corner.
+	//   - As we search, we build a path in a greedy manner,
+	//     where the first match seen is added to the path (this is sub-optimal,
+	//     but provides a decent result in practice). When matches are found,
+	//     we try the next pair of symbols in the lists and follow all matches
+	//     as far as possible.
+	//   - When searching for matches, we search along a diagonal going through
+	//     through the "frontier" point. If no matches are found,
+	//     we advance the frontier towards the opposite corner.
+	//   - This algorithm terminates when either the X coordinates or the
+	//     Y coordinates of the forward and reverse frontier points ever intersect.
+
+	// This algorithm is correct even if searching only in the forward direction
+	// or in the reverse direction. We do both because it is commonly observed
+	// that two lists commonly differ because elements were added to the front
+	// or end of the other list.
+	//
+	// Non-deterministically start with either the forward or reverse direction
+	// to introduce some deliberate instability so that we have the flexibility
+	// to change this algorithm in the future.
+	if flags.Deterministic || randBool {
+		goto forwardSearch
+	} else {
+		goto reverseSearch
+	}
+
+forwardSearch:
+	{
+		// Forward search from the beginning.
+		if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+			goto finishSearch
+		}
+		for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+			// Search in a diagonal pattern for a match.
+			z := zigzag(i)
+			p := point{fwdFrontier.X + z, fwdFrontier.Y - z}
+			switch {
+			case p.X >= revPath.X || p.Y < fwdPath.Y:
+				stop1 = true // Hit top-right corner
+			case p.Y >= revPath.Y || p.X < fwdPath.X:
+				stop2 = true // Hit bottom-left corner
+			case f(p.X, p.Y).Equal():
+				// Match found, so connect the path to this point.
+				fwdPath.connect(p, f)
+				fwdPath.append(Identity)
+				// Follow sequence of matches as far as possible.
+				for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+					if !f(fwdPath.X, fwdPath.Y).Equal() {
+						break
+					}
+					fwdPath.append(Identity)
+				}
+				fwdFrontier = fwdPath.point
+				stop1, stop2 = true, true
+			default:
+				searchBudget-- // Match not found
+			}
+			debug.Update()
+		}
+		// Advance the frontier towards reverse point.
+		if revPath.X-fwdFrontier.X >= revPath.Y-fwdFrontier.Y {
+			fwdFrontier.X++
+		} else {
+			fwdFrontier.Y++
+		}
+		goto reverseSearch
+	}
+
+reverseSearch:
+	{
+		// Reverse search from the end.
+		if fwdFrontier.X >= revFrontier.X || fwdFrontier.Y >= revFrontier.Y || searchBudget == 0 {
+			goto finishSearch
+		}
+		for stop1, stop2, i := false, false, 0; !(stop1 && stop2) && searchBudget > 0; i++ {
+			// Search in a diagonal pattern for a match.
+			z := zigzag(i)
+			p := point{revFrontier.X - z, revFrontier.Y + z}
+			switch {
+			case fwdPath.X >= p.X || revPath.Y < p.Y:
+				stop1 = true // Hit bottom-left corner
+			case fwdPath.Y >= p.Y || revPath.X < p.X:
+				stop2 = true // Hit top-right corner
+			case f(p.X-1, p.Y-1).Equal():
+				// Match found, so connect the path to this point.
+				revPath.connect(p, f)
+				revPath.append(Identity)
+				// Follow sequence of matches as far as possible.
+				for fwdPath.X < revPath.X && fwdPath.Y < revPath.Y {
+					if !f(revPath.X-1, revPath.Y-1).Equal() {
+						break
+					}
+					revPath.append(Identity)
+				}
+				revFrontier = revPath.point
+				stop1, stop2 = true, true
+			default:
+				searchBudget-- // Match not found
+			}
+			debug.Update()
+		}
+		// Advance the frontier towards forward point.
+		if revFrontier.X-fwdPath.X >= revFrontier.Y-fwdPath.Y {
+			revFrontier.X--
+		} else {
+			revFrontier.Y--
+		}
+		goto forwardSearch
+	}
+
+finishSearch:
+	// Join the forward and reverse paths and then append the reverse path.
+	fwdPath.connect(revPath.point, f)
+	for i := len(revPath.es) - 1; i >= 0; i-- {
+		t := revPath.es[i]
+		revPath.es = revPath.es[:i]
+		fwdPath.append(t)
+	}
+	debug.Finish()
+	return fwdPath.es
+}
+
+type path struct {
+	dir   int // +1 if forward, -1 if reverse
+	point     // Leading point of the EditScript path
+	es    EditScript
+}
+
+// connect appends any necessary Identity, Modified, UniqueX, or UniqueY types
+// to the edit-script to connect p.point to dst.
+func (p *path) connect(dst point, f EqualFunc) {
+	if p.dir > 0 {
+		// Connect in forward direction.
+		for dst.X > p.X && dst.Y > p.Y {
+			switch r := f(p.X, p.Y); {
+			case r.Equal():
+				p.append(Identity)
+			case r.Similar():
+				p.append(Modified)
+			case dst.X-p.X >= dst.Y-p.Y:
+				p.append(UniqueX)
+			default:
+				p.append(UniqueY)
+			}
+		}
+		for dst.X > p.X {
+			p.append(UniqueX)
+		}
+		for dst.Y > p.Y {
+			p.append(UniqueY)
+		}
+	} else {
+		// Connect in reverse direction.
+		for p.X > dst.X && p.Y > dst.Y {
+			switch r := f(p.X-1, p.Y-1); {
+			case r.Equal():
+				p.append(Identity)
+			case r.Similar():
+				p.append(Modified)
+			case p.Y-dst.Y >= p.X-dst.X:
+				p.append(UniqueY)
+			default:
+				p.append(UniqueX)
+			}
+		}
+		for p.X > dst.X {
+			p.append(UniqueX)
+		}
+		for p.Y > dst.Y {
+			p.append(UniqueY)
+		}
+	}
+}
+
+func (p *path) append(t EditType) {
+	p.es = append(p.es, t)
+	switch t {
+	case Identity, Modified:
+		p.add(p.dir, p.dir)
+	case UniqueX:
+		p.add(p.dir, 0)
+	case UniqueY:
+		p.add(0, p.dir)
+	}
+	debug.Update()
+}
+
+type point struct{ X, Y int }
+
+func (p *point) add(dx, dy int) { p.X += dx; p.Y += dy }
+
+// zigzag maps a consecutive sequence of integers to a zig-zag sequence.
+//
+//	[0 1 2 3 4 5 ...] => [0 -1 +1 -2 +2 ...]
+func zigzag(x int) int {
+	if x&1 != 0 {
+		x = ^x
+	}
+	return x >> 1
+}

vendor/github.com/google/go-cmp/cmp/internal/flags/flags.go

@@ -0,0 +1,9 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+// Deterministic controls whether the output of Diff should be deterministic.
+// This is only used for testing.
+var Deterministic bool

vendor/github.com/google/go-cmp/cmp/internal/function/func.go

@@ -0,0 +1,99 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package function provides functionality for identifying function types.
+package function
+
+import (
+	"reflect"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+type funcType int
+
+const (
+	_ funcType = iota
+
+	tbFunc  // func(T) bool
+	ttbFunc // func(T, T) bool
+	trbFunc // func(T, R) bool
+	tibFunc // func(T, I) bool
+	trFunc  // func(T) R
+
+	Equal             = ttbFunc // func(T, T) bool
+	EqualAssignable   = tibFunc // func(T, I) bool; encapsulates func(T, T) bool
+	Transformer       = trFunc  // func(T) R
+	ValueFilter       = ttbFunc // func(T, T) bool
+	Less              = ttbFunc // func(T, T) bool
+	ValuePredicate    = tbFunc  // func(T) bool
+	KeyValuePredicate = trbFunc // func(T, R) bool
+)
+
+var boolType = reflect.TypeOf(true)
+
+// IsType reports whether the reflect.Type is of the specified function type.
+func IsType(t reflect.Type, ft funcType) bool {
+	if t == nil || t.Kind() != reflect.Func || t.IsVariadic() {
+		return false
+	}
+	ni, no := t.NumIn(), t.NumOut()
+	switch ft {
+	case tbFunc: // func(T) bool
+		if ni == 1 && no == 1 && t.Out(0) == boolType {
+			return true
+		}
+	case ttbFunc: // func(T, T) bool
+		if ni == 2 && no == 1 && t.In(0) == t.In(1) && t.Out(0) == boolType {
+			return true
+		}
+	case trbFunc: // func(T, R) bool
+		if ni == 2 && no == 1 && t.Out(0) == boolType {
+			return true
+		}
+	case tibFunc: // func(T, I) bool
+		if ni == 2 && no == 1 && t.In(0).AssignableTo(t.In(1)) && t.Out(0) == boolType {
+			return true
+		}
+	case trFunc: // func(T) R
+		if ni == 1 && no == 1 {
+			return true
+		}
+	}
+	return false
+}
+
+var lastIdentRx = regexp.MustCompile(`[_\p{L}][_\p{L}\p{N}]*$`)
+
+// NameOf returns the name of the function value.
+func NameOf(v reflect.Value) string {
+	fnc := runtime.FuncForPC(v.Pointer())
+	if fnc == nil {
+		return "<unknown>"
+	}
+	fullName := fnc.Name() // e.g., "long/path/name/mypkg.(*MyType).(long/path/name/mypkg.myMethod)-fm"
+
+	// Method closures have a "-fm" suffix.
+	fullName = strings.TrimSuffix(fullName, "-fm")
+
+	var name string
+	for len(fullName) > 0 {
+		inParen := strings.HasSuffix(fullName, ")")
+		fullName = strings.TrimSuffix(fullName, ")")
+
+		s := lastIdentRx.FindString(fullName)
+		if s == "" {
+			break
+		}
+		name = s + "." + name
+		fullName = strings.TrimSuffix(fullName, s)
+
+		if i := strings.LastIndexByte(fullName, '('); inParen && i >= 0 {
+			fullName = fullName[:i]
+		}
+		fullName = strings.TrimSuffix(fullName, ".")
+	}
+	return strings.TrimSuffix(name, ".")
+}

vendor/github.com/google/go-cmp/cmp/internal/value/name.go

@@ -0,0 +1,164 @@
+// Copyright 2020, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"reflect"
+	"strconv"
+)
+
+var anyType = reflect.TypeOf((*interface{})(nil)).Elem()
+
+// TypeString is nearly identical to reflect.Type.String,
+// but has an additional option to specify that full type names be used.
+func TypeString(t reflect.Type, qualified bool) string {
+	return string(appendTypeName(nil, t, qualified, false))
+}
+
+func appendTypeName(b []byte, t reflect.Type, qualified, elideFunc bool) []byte {
+	// BUG: Go reflection provides no way to disambiguate two named types
+	// of the same name and within the same package,
+	// but declared within the namespace of different functions.
+
+	// Use the "any" alias instead of "interface{}" for better readability.
+	if t == anyType {
+		return append(b, "any"...)
+	}
+
+	// Named type.
+	if t.Name() != "" {
+		if qualified && t.PkgPath() != "" {
+			b = append(b, '"')
+			b = append(b, t.PkgPath()...)
+			b = append(b, '"')
+			b = append(b, '.')
+			b = append(b, t.Name()...)
+		} else {
+			b = append(b, t.String()...)
+		}
+		return b
+	}
+
+	// Unnamed type.
+	switch k := t.Kind(); k {
+	case reflect.Bool, reflect.String, reflect.UnsafePointer,
+		reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+		reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+		b = append(b, k.String()...)
+	case reflect.Chan:
+		if t.ChanDir() == reflect.RecvDir {
+			b = append(b, "<-"...)
+		}
+		b = append(b, "chan"...)
+		if t.ChanDir() == reflect.SendDir {
+			b = append(b, "<-"...)
+		}
+		b = append(b, ' ')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Func:
+		if !elideFunc {
+			b = append(b, "func"...)
+		}
+		b = append(b, '(')
+		for i := 0; i < t.NumIn(); i++ {
+			if i > 0 {
+				b = append(b, ", "...)
+			}
+			if i == t.NumIn()-1 && t.IsVariadic() {
+				b = append(b, "..."...)
+				b = appendTypeName(b, t.In(i).Elem(), qualified, false)
+			} else {
+				b = appendTypeName(b, t.In(i), qualified, false)
+			}
+		}
+		b = append(b, ')')
+		switch t.NumOut() {
+		case 0:
+			// Do nothing
+		case 1:
+			b = append(b, ' ')
+			b = appendTypeName(b, t.Out(0), qualified, false)
+		default:
+			b = append(b, " ("...)
+			for i := 0; i < t.NumOut(); i++ {
+				if i > 0 {
+					b = append(b, ", "...)
+				}
+				b = appendTypeName(b, t.Out(i), qualified, false)
+			}
+			b = append(b, ')')
+		}
+	case reflect.Struct:
+		b = append(b, "struct{ "...)
+		for i := 0; i < t.NumField(); i++ {
+			if i > 0 {
+				b = append(b, "; "...)
+			}
+			sf := t.Field(i)
+			if !sf.Anonymous {
+				if qualified && sf.PkgPath != "" {
+					b = append(b, '"')
+					b = append(b, sf.PkgPath...)
+					b = append(b, '"')
+					b = append(b, '.')
+				}
+				b = append(b, sf.Name...)
+				b = append(b, ' ')
+			}
+			b = appendTypeName(b, sf.Type, qualified, false)
+			if sf.Tag != "" {
+				b = append(b, ' ')
+				b = strconv.AppendQuote(b, string(sf.Tag))
+			}
+		}
+		if b[len(b)-1] == ' ' {
+			b = b[:len(b)-1]
+		} else {
+			b = append(b, ' ')
+		}
+		b = append(b, '}')
+	case reflect.Slice, reflect.Array:
+		b = append(b, '[')
+		if k == reflect.Array {
+			b = strconv.AppendUint(b, uint64(t.Len()), 10)
+		}
+		b = append(b, ']')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Map:
+		b = append(b, "map["...)
+		b = appendTypeName(b, t.Key(), qualified, false)
+		b = append(b, ']')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Ptr:
+		b = append(b, '*')
+		b = appendTypeName(b, t.Elem(), qualified, false)
+	case reflect.Interface:
+		b = append(b, "interface{ "...)
+		for i := 0; i < t.NumMethod(); i++ {
+			if i > 0 {
+				b = append(b, "; "...)
+			}
+			m := t.Method(i)
+			if qualified && m.PkgPath != "" {
+				b = append(b, '"')
+				b = append(b, m.PkgPath...)
+				b = append(b, '"')
+				b = append(b, '.')
+			}
+			b = append(b, m.Name...)
+			b = appendTypeName(b, m.Type, qualified, true)
+		}
+		if b[len(b)-1] == ' ' {
+			b = b[:len(b)-1]
+		} else {
+			b = append(b, ' ')
+		}
+		b = append(b, '}')
+	default:
+		panic("invalid kind: " + k.String())
+	}
+	return b
+}

vendor/github.com/google/go-cmp/cmp/internal/value/pointer.go

@@ -0,0 +1,34 @@
+// Copyright 2018, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// Pointer is an opaque typed pointer and is guaranteed to be comparable.
+type Pointer struct {
+	p unsafe.Pointer
+	t reflect.Type
+}
+
+// PointerOf returns a Pointer from v, which must be a
+// reflect.Ptr, reflect.Slice, or reflect.Map.
+func PointerOf(v reflect.Value) Pointer {
+	// The proper representation of a pointer is unsafe.Pointer,
+	// which is necessary if the GC ever uses a moving collector.
+	return Pointer{unsafe.Pointer(v.Pointer()), v.Type()}
+}
+
+// IsNil reports whether the pointer is nil.
+func (p Pointer) IsNil() bool {
+	return p.p == nil
+}
+
+// Uintptr returns the pointer as a uintptr.
+func (p Pointer) Uintptr() uintptr {
+	return uintptr(p.p)
+}

vendor/github.com/google/go-cmp/cmp/internal/value/sort.go

@@ -0,0 +1,106 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package value
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"sort"
+)
+
+// SortKeys sorts a list of map keys, deduplicating keys if necessary.
+// The type of each value must be comparable.
+func SortKeys(vs []reflect.Value) []reflect.Value {
+	if len(vs) == 0 {
+		return vs
+	}
+
+	// Sort the map keys.
+	sort.SliceStable(vs, func(i, j int) bool { return isLess(vs[i], vs[j]) })
+
+	// Deduplicate keys (fails for NaNs).
+	vs2 := vs[:1]
+	for _, v := range vs[1:] {
+		if isLess(vs2[len(vs2)-1], v) {
+			vs2 = append(vs2, v)
+		}
+	}
+	return vs2
+}
+
+// isLess is a generic function for sorting arbitrary map keys.
+// The inputs must be of the same type and must be comparable.
+func isLess(x, y reflect.Value) bool {
+	switch x.Type().Kind() {
+	case reflect.Bool:
+		return !x.Bool() && y.Bool()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return x.Int() < y.Int()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return x.Uint() < y.Uint()
+	case reflect.Float32, reflect.Float64:
+		// NOTE: This does not sort -0 as less than +0
+		// since Go maps treat -0 and +0 as equal keys.
+		fx, fy := x.Float(), y.Float()
+		return fx < fy || math.IsNaN(fx) && !math.IsNaN(fy)
+	case reflect.Complex64, reflect.Complex128:
+		cx, cy := x.Complex(), y.Complex()
+		rx, ix, ry, iy := real(cx), imag(cx), real(cy), imag(cy)
+		if rx == ry || (math.IsNaN(rx) && math.IsNaN(ry)) {
+			return ix < iy || math.IsNaN(ix) && !math.IsNaN(iy)
+		}
+		return rx < ry || math.IsNaN(rx) && !math.IsNaN(ry)
+	case reflect.Ptr, reflect.UnsafePointer, reflect.Chan:
+		return x.Pointer() < y.Pointer()
+	case reflect.String:
+		return x.String() < y.String()
+	case reflect.Array:
+		for i := 0; i < x.Len(); i++ {
+			if isLess(x.Index(i), y.Index(i)) {
+				return true
+			}
+			if isLess(y.Index(i), x.Index(i)) {
+				return false
+			}
+		}
+		return false
+	case reflect.Struct:
+		for i := 0; i < x.NumField(); i++ {
+			if isLess(x.Field(i), y.Field(i)) {
+				return true
+			}
+			if isLess(y.Field(i), x.Field(i)) {
+				return false
+			}
+		}
+		return false
+	case reflect.Interface:
+		vx, vy := x.Elem(), y.Elem()
+		if !vx.IsValid() || !vy.IsValid() {
+			return !vx.IsValid() && vy.IsValid()
+		}
+		tx, ty := vx.Type(), vy.Type()
+		if tx == ty {
+			return isLess(x.Elem(), y.Elem())
+		}
+		if tx.Kind() != ty.Kind() {
+			return vx.Kind() < vy.Kind()
+		}
+		if tx.String() != ty.String() {
+			return tx.String() < ty.String()
+		}
+		if tx.PkgPath() != ty.PkgPath() {
+			return tx.PkgPath() < ty.PkgPath()
+		}
+		// This can happen in rare situations, so we fallback to just comparing
+		// the unique pointer for a reflect.Type. This guarantees deterministic
+		// ordering within a program, but it is obviously not stable.
+		return reflect.ValueOf(vx.Type()).Pointer() < reflect.ValueOf(vy.Type()).Pointer()
+	default:
+		// Must be Func, Map, or Slice; which are not comparable.
+		panic(fmt.Sprintf("%T is not comparable", x.Type()))
+	}
+}

vendor/github.com/google/go-cmp/cmp/options.go

@@ -0,0 +1,554 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"regexp"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/function"
+)
+
+// Option configures for specific behavior of [Equal] and [Diff]. In particular,
+// the fundamental Option functions ([Ignore], [Transformer], and [Comparer]),
+// configure how equality is determined.
+//
+// The fundamental options may be composed with filters ([FilterPath] and
+// [FilterValues]) to control the scope over which they are applied.
+//
+// The [github.com/google/go-cmp/cmp/cmpopts] package provides helper functions
+// for creating options that may be used with [Equal] and [Diff].
+type Option interface {
+	// filter applies all filters and returns the option that remains.
+	// Each option may only read s.curPath and call s.callTTBFunc.
+	//
+	// An Options is returned only if multiple comparers or transformers
+	// can apply simultaneously and will only contain values of those types
+	// or sub-Options containing values of those types.
+	filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption
+}
+
+// applicableOption represents the following types:
+//
+//	Fundamental: ignore | validator | *comparer | *transformer
+//	Grouping:    Options
+type applicableOption interface {
+	Option
+
+	// apply executes the option, which may mutate s or panic.
+	apply(s *state, vx, vy reflect.Value)
+}
+
+// coreOption represents the following types:
+//
+//	Fundamental: ignore | validator | *comparer | *transformer
+//	Filters:     *pathFilter | *valuesFilter
+type coreOption interface {
+	Option
+	isCore()
+}
+
+type core struct{}
+
+func (core) isCore() {}
+
+// Options is a list of [Option] values that also satisfies the [Option] interface.
+// Helper comparison packages may return an Options value when packing multiple
+// [Option] values into a single [Option]. When this package processes an Options,
+// it will be implicitly expanded into a flat list.
+//
+// Applying a filter on an Options is equivalent to applying that same filter
+// on all individual options held within.
+type Options []Option
+
+func (opts Options) filter(s *state, t reflect.Type, vx, vy reflect.Value) (out applicableOption) {
+	for _, opt := range opts {
+		switch opt := opt.filter(s, t, vx, vy); opt.(type) {
+		case ignore:
+			return ignore{} // Only ignore can short-circuit evaluation
+		case validator:
+			out = validator{} // Takes precedence over comparer or transformer
+		case *comparer, *transformer, Options:
+			switch out.(type) {
+			case nil:
+				out = opt
+			case validator:
+				// Keep validator
+			case *comparer, *transformer, Options:
+				out = Options{out, opt} // Conflicting comparers or transformers
+			}
+		}
+	}
+	return out
+}
+
+func (opts Options) apply(s *state, _, _ reflect.Value) {
+	const warning = "ambiguous set of applicable options"
+	const help = "consider using filters to ensure at most one Comparer or Transformer may apply"
+	var ss []string
+	for _, opt := range flattenOptions(nil, opts) {
+		ss = append(ss, fmt.Sprint(opt))
+	}
+	set := strings.Join(ss, "\n\t")
+	panic(fmt.Sprintf("%s at %#v:\n\t%s\n%s", warning, s.curPath, set, help))
+}
+
+func (opts Options) String() string {
+	var ss []string
+	for _, opt := range opts {
+		ss = append(ss, fmt.Sprint(opt))
+	}
+	return fmt.Sprintf("Options{%s}", strings.Join(ss, ", "))
+}
+
+// FilterPath returns a new [Option] where opt is only evaluated if filter f
+// returns true for the current [Path] in the value tree.
+//
+// This filter is called even if a slice element or map entry is missing and
+// provides an opportunity to ignore such cases. The filter function must be
+// symmetric such that the filter result is identical regardless of whether the
+// missing value is from x or y.
+//
+// The option passed in may be an [Ignore], [Transformer], [Comparer], [Options], or
+// a previously filtered [Option].
+func FilterPath(f func(Path) bool, opt Option) Option {
+	if f == nil {
+		panic("invalid path filter function")
+	}
+	if opt := normalizeOption(opt); opt != nil {
+		return &pathFilter{fnc: f, opt: opt}
+	}
+	return nil
+}
+
+type pathFilter struct {
+	core
+	fnc func(Path) bool
+	opt Option
+}
+
+func (f pathFilter) filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption {
+	if f.fnc(s.curPath) {
+		return f.opt.filter(s, t, vx, vy)
+	}
+	return nil
+}
+
+func (f pathFilter) String() string {
+	return fmt.Sprintf("FilterPath(%s, %v)", function.NameOf(reflect.ValueOf(f.fnc)), f.opt)
+}
+
+// FilterValues returns a new [Option] where opt is only evaluated if filter f,
+// which is a function of the form "func(T, T) bool", returns true for the
+// current pair of values being compared. If either value is invalid or
+// the type of the values is not assignable to T, then this filter implicitly
+// returns false.
+//
+// The filter function must be
+// symmetric (i.e., agnostic to the order of the inputs) and
+// deterministic (i.e., produces the same result when given the same inputs).
+// If T is an interface, it is possible that f is called with two values with
+// different concrete types that both implement T.
+//
+// The option passed in may be an [Ignore], [Transformer], [Comparer], [Options], or
+// a previously filtered [Option].
+func FilterValues(f interface{}, opt Option) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.ValueFilter) || v.IsNil() {
+		panic(fmt.Sprintf("invalid values filter function: %T", f))
+	}
+	if opt := normalizeOption(opt); opt != nil {
+		vf := &valuesFilter{fnc: v, opt: opt}
+		if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+			vf.typ = ti
+		}
+		return vf
+	}
+	return nil
+}
+
+type valuesFilter struct {
+	core
+	typ reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+	opt Option
+}
+
+func (f valuesFilter) filter(s *state, t reflect.Type, vx, vy reflect.Value) applicableOption {
+	if !vx.IsValid() || !vx.CanInterface() || !vy.IsValid() || !vy.CanInterface() {
+		return nil
+	}
+	if (f.typ == nil || t.AssignableTo(f.typ)) && s.callTTBFunc(f.fnc, vx, vy) {
+		return f.opt.filter(s, t, vx, vy)
+	}
+	return nil
+}
+
+func (f valuesFilter) String() string {
+	return fmt.Sprintf("FilterValues(%s, %v)", function.NameOf(f.fnc), f.opt)
+}
+
+// Ignore is an [Option] that causes all comparisons to be ignored.
+// This value is intended to be combined with [FilterPath] or [FilterValues].
+// It is an error to pass an unfiltered Ignore option to [Equal].
+func Ignore() Option { return ignore{} }
+
+type ignore struct{ core }
+
+func (ignore) isFiltered() bool                                                     { return false }
+func (ignore) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption { return ignore{} }
+func (ignore) apply(s *state, _, _ reflect.Value)                                   { s.report(true, reportByIgnore) }
+func (ignore) String() string                                                       { return "Ignore()" }
+
+// validator is a sentinel Option type to indicate that some options could not
+// be evaluated due to unexported fields, missing slice elements, or
+// missing map entries. Both values are validator only for unexported fields.
+type validator struct{ core }
+
+func (validator) filter(_ *state, _ reflect.Type, vx, vy reflect.Value) applicableOption {
+	if !vx.IsValid() || !vy.IsValid() {
+		return validator{}
+	}
+	if !vx.CanInterface() || !vy.CanInterface() {
+		return validator{}
+	}
+	return nil
+}
+func (validator) apply(s *state, vx, vy reflect.Value) {
+	// Implies missing slice element or map entry.
+	if !vx.IsValid() || !vy.IsValid() {
+		s.report(vx.IsValid() == vy.IsValid(), 0)
+		return
+	}
+
+	// Unable to Interface implies unexported field without visibility access.
+	if !vx.CanInterface() || !vy.CanInterface() {
+		help := "consider using a custom Comparer; if you control the implementation of type, you can also consider using an Exporter, AllowUnexported, or cmpopts.IgnoreUnexported"
+		var name string
+		if t := s.curPath.Index(-2).Type(); t.Name() != "" {
+			// Named type with unexported fields.
+			name = fmt.Sprintf("%q.%v", t.PkgPath(), t.Name()) // e.g., "path/to/package".MyType
+			if _, ok := reflect.New(t).Interface().(error); ok {
+				help = "consider using cmpopts.EquateErrors to compare error values"
+			} else if t.Comparable() {
+				help = "consider using cmpopts.EquateComparable to compare comparable Go types"
+			}
+		} else {
+			// Unnamed type with unexported fields. Derive PkgPath from field.
+			var pkgPath string
+			for i := 0; i < t.NumField() && pkgPath == ""; i++ {
+				pkgPath = t.Field(i).PkgPath
+			}
+			name = fmt.Sprintf("%q.(%v)", pkgPath, t.String()) // e.g., "path/to/package".(struct { a int })
+		}
+		panic(fmt.Sprintf("cannot handle unexported field at %#v:\n\t%v\n%s", s.curPath, name, help))
+	}
+
+	panic("not reachable")
+}
+
+// identRx represents a valid identifier according to the Go specification.
+const identRx = `[_\p{L}][_\p{L}\p{N}]*`
+
+var identsRx = regexp.MustCompile(`^` + identRx + `(\.` + identRx + `)*$`)
+
+// Transformer returns an [Option] that applies a transformation function that
+// converts values of a certain type into that of another.
+//
+// The transformer f must be a function "func(T) R" that converts values of
+// type T to those of type R and is implicitly filtered to input values
+// assignable to T. The transformer must not mutate T in any way.
+//
+// To help prevent some cases of infinite recursive cycles applying the
+// same transform to the output of itself (e.g., in the case where the
+// input and output types are the same), an implicit filter is added such that
+// a transformer is applicable only if that exact transformer is not already
+// in the tail of the [Path] since the last non-[Transform] step.
+// For situations where the implicit filter is still insufficient,
+// consider using [github.com/google/go-cmp/cmp/cmpopts.AcyclicTransformer],
+// which adds a filter to prevent the transformer from
+// being recursively applied upon itself.
+//
+// The name is a user provided label that is used as the [Transform.Name] in the
+// transformation [PathStep] (and eventually shown in the [Diff] output).
+// The name must be a valid identifier or qualified identifier in Go syntax.
+// If empty, an arbitrary name is used.
+func Transformer(name string, f interface{}) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.Transformer) || v.IsNil() {
+		panic(fmt.Sprintf("invalid transformer function: %T", f))
+	}
+	if name == "" {
+		name = function.NameOf(v)
+		if !identsRx.MatchString(name) {
+			name = "λ" // Lambda-symbol as placeholder name
+		}
+	} else if !identsRx.MatchString(name) {
+		panic(fmt.Sprintf("invalid name: %q", name))
+	}
+	tr := &transformer{name: name, fnc: reflect.ValueOf(f)}
+	if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+		tr.typ = ti
+	}
+	return tr
+}
+
+type transformer struct {
+	core
+	name string
+	typ  reflect.Type  // T
+	fnc  reflect.Value // func(T) R
+}
+
+func (tr *transformer) isFiltered() bool { return tr.typ != nil }
+
+func (tr *transformer) filter(s *state, t reflect.Type, _, _ reflect.Value) applicableOption {
+	for i := len(s.curPath) - 1; i >= 0; i-- {
+		if t, ok := s.curPath[i].(Transform); !ok {
+			break // Hit most recent non-Transform step
+		} else if tr == t.trans {
+			return nil // Cannot directly use same Transform
+		}
+	}
+	if tr.typ == nil || t.AssignableTo(tr.typ) {
+		return tr
+	}
+	return nil
+}
+
+func (tr *transformer) apply(s *state, vx, vy reflect.Value) {
+	step := Transform{&transform{pathStep{typ: tr.fnc.Type().Out(0)}, tr}}
+	vvx := s.callTRFunc(tr.fnc, vx, step)
+	vvy := s.callTRFunc(tr.fnc, vy, step)
+	step.vx, step.vy = vvx, vvy
+	s.compareAny(step)
+}
+
+func (tr transformer) String() string {
+	return fmt.Sprintf("Transformer(%s, %s)", tr.name, function.NameOf(tr.fnc))
+}
+
+// Comparer returns an [Option] that determines whether two values are equal
+// to each other.
+//
+// The comparer f must be a function "func(T, T) bool" and is implicitly
+// filtered to input values assignable to T. If T is an interface, it is
+// possible that f is called with two values of different concrete types that
+// both implement T.
+//
+// The equality function must be:
+//   - Symmetric: equal(x, y) == equal(y, x)
+//   - Deterministic: equal(x, y) == equal(x, y)
+//   - Pure: equal(x, y) does not modify x or y
+func Comparer(f interface{}) Option {
+	v := reflect.ValueOf(f)
+	if !function.IsType(v.Type(), function.Equal) || v.IsNil() {
+		panic(fmt.Sprintf("invalid comparer function: %T", f))
+	}
+	cm := &comparer{fnc: v}
+	if ti := v.Type().In(0); ti.Kind() != reflect.Interface || ti.NumMethod() > 0 {
+		cm.typ = ti
+	}
+	return cm
+}
+
+type comparer struct {
+	core
+	typ reflect.Type  // T
+	fnc reflect.Value // func(T, T) bool
+}
+
+func (cm *comparer) isFiltered() bool { return cm.typ != nil }
+
+func (cm *comparer) filter(_ *state, t reflect.Type, _, _ reflect.Value) applicableOption {
+	if cm.typ == nil || t.AssignableTo(cm.typ) {
+		return cm
+	}
+	return nil
+}
+
+func (cm *comparer) apply(s *state, vx, vy reflect.Value) {
+	eq := s.callTTBFunc(cm.fnc, vx, vy)
+	s.report(eq, reportByFunc)
+}
+
+func (cm comparer) String() string {
+	return fmt.Sprintf("Comparer(%s)", function.NameOf(cm.fnc))
+}
+
+// Exporter returns an [Option] that specifies whether [Equal] is allowed to
+// introspect into the unexported fields of certain struct types.
+//
+// Users of this option must understand that comparing on unexported fields
+// from external packages is not safe since changes in the internal
+// implementation of some external package may cause the result of [Equal]
+// to unexpectedly change. However, it may be valid to use this option on types
+// defined in an internal package where the semantic meaning of an unexported
+// field is in the control of the user.
+//
+// In many cases, a custom [Comparer] should be used instead that defines
+// equality as a function of the public API of a type rather than the underlying
+// unexported implementation.
+//
+// For example, the [reflect.Type] documentation defines equality to be determined
+// by the == operator on the interface (essentially performing a shallow pointer
+// comparison) and most attempts to compare *[regexp.Regexp] types are interested
+// in only checking that the regular expression strings are equal.
+// Both of these are accomplished using [Comparer] options:
+//
+//	Comparer(func(x, y reflect.Type) bool { return x == y })
+//	Comparer(func(x, y *regexp.Regexp) bool { return x.String() == y.String() })
+//
+// In other cases, the [github.com/google/go-cmp/cmp/cmpopts.IgnoreUnexported]
+// option can be used to ignore all unexported fields on specified struct types.
+func Exporter(f func(reflect.Type) bool) Option {
+	return exporter(f)
+}
+
+type exporter func(reflect.Type) bool
+
+func (exporter) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption {
+	panic("not implemented")
+}
+
+// AllowUnexported returns an [Option] that allows [Equal] to forcibly introspect
+// unexported fields of the specified struct types.
+//
+// See [Exporter] for the proper use of this option.
+func AllowUnexported(types ...interface{}) Option {
+	m := make(map[reflect.Type]bool)
+	for _, typ := range types {
+		t := reflect.TypeOf(typ)
+		if t.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("invalid struct type: %T", typ))
+		}
+		m[t] = true
+	}
+	return exporter(func(t reflect.Type) bool { return m[t] })
+}
+
+// Result represents the comparison result for a single node and
+// is provided by cmp when calling Report (see [Reporter]).
+type Result struct {
+	_     [0]func() // Make Result incomparable
+	flags resultFlags
+}
+
+// Equal reports whether the node was determined to be equal or not.
+// As a special case, ignored nodes are considered equal.
+func (r Result) Equal() bool {
+	return r.flags&(reportEqual|reportByIgnore) != 0
+}
+
+// ByIgnore reports whether the node is equal because it was ignored.
+// This never reports true if [Result.Equal] reports false.
+func (r Result) ByIgnore() bool {
+	return r.flags&reportByIgnore != 0
+}
+
+// ByMethod reports whether the Equal method determined equality.
+func (r Result) ByMethod() bool {
+	return r.flags&reportByMethod != 0
+}
+
+// ByFunc reports whether a [Comparer] function determined equality.
+func (r Result) ByFunc() bool {
+	return r.flags&reportByFunc != 0
+}
+
+// ByCycle reports whether a reference cycle was detected.
+func (r Result) ByCycle() bool {
+	return r.flags&reportByCycle != 0
+}
+
+type resultFlags uint
+
+const (
+	_ resultFlags = (1 << iota) / 2
+
+	reportEqual
+	reportUnequal
+	reportByIgnore
+	reportByMethod
+	reportByFunc
+	reportByCycle
+)
+
+// Reporter is an [Option] that can be passed to [Equal]. When [Equal] traverses
+// the value trees, it calls PushStep as it descends into each node in the
+// tree and PopStep as it ascend out of the node. The leaves of the tree are
+// either compared (determined to be equal or not equal) or ignored and reported
+// as such by calling the Report method.
+func Reporter(r interface {
+	// PushStep is called when a tree-traversal operation is performed.
+	// The PathStep itself is only valid until the step is popped.
+	// The PathStep.Values are valid for the duration of the entire traversal
+	// and must not be mutated.
+	//
+	// Equal always calls PushStep at the start to provide an operation-less
+	// PathStep used to report the root values.
+	//
+	// Within a slice, the exact set of inserted, removed, or modified elements
+	// is unspecified and may change in future implementations.
+	// The entries of a map are iterated through in an unspecified order.
+	PushStep(PathStep)
+
+	// Report is called exactly once on leaf nodes to report whether the
+	// comparison identified the node as equal, unequal, or ignored.
+	// A leaf node is one that is immediately preceded by and followed by
+	// a pair of PushStep and PopStep calls.
+	Report(Result)
+
+	// PopStep ascends back up the value tree.
+	// There is always a matching pop call for every push call.
+	PopStep()
+}) Option {
+	return reporter{r}
+}
+
+type reporter struct{ reporterIface }
+type reporterIface interface {
+	PushStep(PathStep)
+	Report(Result)
+	PopStep()
+}
+
+func (reporter) filter(_ *state, _ reflect.Type, _, _ reflect.Value) applicableOption {
+	panic("not implemented")
+}
+
+// normalizeOption normalizes the input options such that all Options groups
+// are flattened and groups with a single element are reduced to that element.
+// Only coreOptions and Options containing coreOptions are allowed.
+func normalizeOption(src Option) Option {
+	switch opts := flattenOptions(nil, Options{src}); len(opts) {
+	case 0:
+		return nil
+	case 1:
+		return opts[0]
+	default:
+		return opts
+	}
+}
+
+// flattenOptions copies all options in src to dst as a flat list.
+// Only coreOptions and Options containing coreOptions are allowed.
+func flattenOptions(dst, src Options) Options {
+	for _, opt := range src {
+		switch opt := opt.(type) {
+		case nil:
+			continue
+		case Options:
+			dst = flattenOptions(dst, opt)
+		case coreOption:
+			dst = append(dst, opt)
+		default:
+			panic(fmt.Sprintf("invalid option type: %T", opt))
+		}
+	}
+	return dst
+}

vendor/github.com/google/go-cmp/cmp/path.go

@@ -0,0 +1,390 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+// Path is a list of [PathStep] describing the sequence of operations to get
+// from some root type to the current position in the value tree.
+// The first Path element is always an operation-less [PathStep] that exists
+// simply to identify the initial type.
+//
+// When traversing structs with embedded structs, the embedded struct will
+// always be accessed as a field before traversing the fields of the
+// embedded struct themselves. That is, an exported field from the
+// embedded struct will never be accessed directly from the parent struct.
+type Path []PathStep
+
+// PathStep is a union-type for specific operations to traverse
+// a value's tree structure. Users of this package never need to implement
+// these types as values of this type will be returned by this package.
+//
+// Implementations of this interface:
+//   - [StructField]
+//   - [SliceIndex]
+//   - [MapIndex]
+//   - [Indirect]
+//   - [TypeAssertion]
+//   - [Transform]
+type PathStep interface {
+	String() string
+
+	// Type is the resulting type after performing the path step.
+	Type() reflect.Type
+
+	// Values is the resulting values after performing the path step.
+	// The type of each valid value is guaranteed to be identical to Type.
+	//
+	// In some cases, one or both may be invalid or have restrictions:
+	//   - For StructField, both are not interface-able if the current field
+	//     is unexported and the struct type is not explicitly permitted by
+	//     an Exporter to traverse unexported fields.
+	//   - For SliceIndex, one may be invalid if an element is missing from
+	//     either the x or y slice.
+	//   - For MapIndex, one may be invalid if an entry is missing from
+	//     either the x or y map.
+	//
+	// The provided values must not be mutated.
+	Values() (vx, vy reflect.Value)
+}
+
+var (
+	_ PathStep = StructField{}
+	_ PathStep = SliceIndex{}
+	_ PathStep = MapIndex{}
+	_ PathStep = Indirect{}
+	_ PathStep = TypeAssertion{}
+	_ PathStep = Transform{}
+)
+
+func (pa *Path) push(s PathStep) {
+	*pa = append(*pa, s)
+}
+
+func (pa *Path) pop() {
+	*pa = (*pa)[:len(*pa)-1]
+}
+
+// Last returns the last [PathStep] in the Path.
+// If the path is empty, this returns a non-nil [PathStep]
+// that reports a nil [PathStep.Type].
+func (pa Path) Last() PathStep {
+	return pa.Index(-1)
+}
+
+// Index returns the ith step in the Path and supports negative indexing.
+// A negative index starts counting from the tail of the Path such that -1
+// refers to the last step, -2 refers to the second-to-last step, and so on.
+// If index is invalid, this returns a non-nil [PathStep]
+// that reports a nil [PathStep.Type].
+func (pa Path) Index(i int) PathStep {
+	if i < 0 {
+		i = len(pa) + i
+	}
+	if i < 0 || i >= len(pa) {
+		return pathStep{}
+	}
+	return pa[i]
+}
+
+// String returns the simplified path to a node.
+// The simplified path only contains struct field accesses.
+//
+// For example:
+//
+//	MyMap.MySlices.MyField
+func (pa Path) String() string {
+	var ss []string
+	for _, s := range pa {
+		if _, ok := s.(StructField); ok {
+			ss = append(ss, s.String())
+		}
+	}
+	return strings.TrimPrefix(strings.Join(ss, ""), ".")
+}
+
+// GoString returns the path to a specific node using Go syntax.
+//
+// For example:
+//
+//	(*root.MyMap["key"].(*mypkg.MyStruct).MySlices)[2][3].MyField
+func (pa Path) GoString() string {
+	var ssPre, ssPost []string
+	var numIndirect int
+	for i, s := range pa {
+		var nextStep PathStep
+		if i+1 < len(pa) {
+			nextStep = pa[i+1]
+		}
+		switch s := s.(type) {
+		case Indirect:
+			numIndirect++
+			pPre, pPost := "(", ")"
+			switch nextStep.(type) {
+			case Indirect:
+				continue // Next step is indirection, so let them batch up
+			case StructField:
+				numIndirect-- // Automatic indirection on struct fields
+			case nil:
+				pPre, pPost = "", "" // Last step; no need for parenthesis
+			}
+			if numIndirect > 0 {
+				ssPre = append(ssPre, pPre+strings.Repeat("*", numIndirect))
+				ssPost = append(ssPost, pPost)
+			}
+			numIndirect = 0
+			continue
+		case Transform:
+			ssPre = append(ssPre, s.trans.name+"(")
+			ssPost = append(ssPost, ")")
+			continue
+		}
+		ssPost = append(ssPost, s.String())
+	}
+	for i, j := 0, len(ssPre)-1; i < j; i, j = i+1, j-1 {
+		ssPre[i], ssPre[j] = ssPre[j], ssPre[i]
+	}
+	return strings.Join(ssPre, "") + strings.Join(ssPost, "")
+}
+
+type pathStep struct {
+	typ    reflect.Type
+	vx, vy reflect.Value
+}
+
+func (ps pathStep) Type() reflect.Type             { return ps.typ }
+func (ps pathStep) Values() (vx, vy reflect.Value) { return ps.vx, ps.vy }
+func (ps pathStep) String() string {
+	if ps.typ == nil {
+		return "<nil>"
+	}
+	s := value.TypeString(ps.typ, false)
+	if s == "" || strings.ContainsAny(s, "{}\n") {
+		return "root" // Type too simple or complex to print
+	}
+	return fmt.Sprintf("{%s}", s)
+}
+
+// StructField is a [PathStep] that represents a struct field access
+// on a field called [StructField.Name].
+type StructField struct{ *structField }
+type structField struct {
+	pathStep
+	name string
+	idx  int
+
+	// These fields are used for forcibly accessing an unexported field.
+	// pvx, pvy, and field are only valid if unexported is true.
+	unexported bool
+	mayForce   bool                // Forcibly allow visibility
+	paddr      bool                // Was parent addressable?
+	pvx, pvy   reflect.Value       // Parent values (always addressable)
+	field      reflect.StructField // Field information
+}
+
+func (sf StructField) Type() reflect.Type { return sf.typ }
+func (sf StructField) Values() (vx, vy reflect.Value) {
+	if !sf.unexported {
+		return sf.vx, sf.vy // CanInterface reports true
+	}
+
+	// Forcibly obtain read-write access to an unexported struct field.
+	if sf.mayForce {
+		vx = retrieveUnexportedField(sf.pvx, sf.field, sf.paddr)
+		vy = retrieveUnexportedField(sf.pvy, sf.field, sf.paddr)
+		return vx, vy // CanInterface reports true
+	}
+	return sf.vx, sf.vy // CanInterface reports false
+}
+func (sf StructField) String() string { return fmt.Sprintf(".%s", sf.name) }
+
+// Name is the field name.
+func (sf StructField) Name() string { return sf.name }
+
+// Index is the index of the field in the parent struct type.
+// See [reflect.Type.Field].
+func (sf StructField) Index() int { return sf.idx }
+
+// SliceIndex is a [PathStep] that represents an index operation on
+// a slice or array at some index [SliceIndex.Key].
+type SliceIndex struct{ *sliceIndex }
+type sliceIndex struct {
+	pathStep
+	xkey, ykey int
+	isSlice    bool // False for reflect.Array
+}
+
+func (si SliceIndex) Type() reflect.Type             { return si.typ }
+func (si SliceIndex) Values() (vx, vy reflect.Value) { return si.vx, si.vy }
+func (si SliceIndex) String() string {
+	switch {
+	case si.xkey == si.ykey:
+		return fmt.Sprintf("[%d]", si.xkey)
+	case si.ykey == -1:
+		// [5->?] means "I don't know where X[5] went"
+		return fmt.Sprintf("[%d->?]", si.xkey)
+	case si.xkey == -1:
+		// [?->3] means "I don't know where Y[3] came from"
+		return fmt.Sprintf("[?->%d]", si.ykey)
+	default:
+		// [5->3] means "X[5] moved to Y[3]"
+		return fmt.Sprintf("[%d->%d]", si.xkey, si.ykey)
+	}
+}
+
+// Key is the index key; it may return -1 if in a split state
+func (si SliceIndex) Key() int {
+	if si.xkey != si.ykey {
+		return -1
+	}
+	return si.xkey
+}
+
+// SplitKeys are the indexes for indexing into slices in the
+// x and y values, respectively. These indexes may differ due to the
+// insertion or removal of an element in one of the slices, causing
+// all of the indexes to be shifted. If an index is -1, then that
+// indicates that the element does not exist in the associated slice.
+//
+// [SliceIndex.Key] is guaranteed to return -1 if and only if the indexes
+// returned by SplitKeys are not the same. SplitKeys will never return -1 for
+// both indexes.
+func (si SliceIndex) SplitKeys() (ix, iy int) { return si.xkey, si.ykey }
+
+// MapIndex is a [PathStep] that represents an index operation on a map at some index Key.
+type MapIndex struct{ *mapIndex }
+type mapIndex struct {
+	pathStep
+	key reflect.Value
+}
+
+func (mi MapIndex) Type() reflect.Type             { return mi.typ }
+func (mi MapIndex) Values() (vx, vy reflect.Value) { return mi.vx, mi.vy }
+func (mi MapIndex) String() string                 { return fmt.Sprintf("[%#v]", mi.key) }
+
+// Key is the value of the map key.
+func (mi MapIndex) Key() reflect.Value { return mi.key }
+
+// Indirect is a [PathStep] that represents pointer indirection on the parent type.
+type Indirect struct{ *indirect }
+type indirect struct {
+	pathStep
+}
+
+func (in Indirect) Type() reflect.Type             { return in.typ }
+func (in Indirect) Values() (vx, vy reflect.Value) { return in.vx, in.vy }
+func (in Indirect) String() string                 { return "*" }
+
+// TypeAssertion is a [PathStep] that represents a type assertion on an interface.
+type TypeAssertion struct{ *typeAssertion }
+type typeAssertion struct {
+	pathStep
+}
+
+func (ta TypeAssertion) Type() reflect.Type             { return ta.typ }
+func (ta TypeAssertion) Values() (vx, vy reflect.Value) { return ta.vx, ta.vy }
+func (ta TypeAssertion) String() string                 { return fmt.Sprintf(".(%v)", value.TypeString(ta.typ, false)) }
+
+// Transform is a [PathStep] that represents a transformation
+// from the parent type to the current type.
+type Transform struct{ *transform }
+type transform struct {
+	pathStep
+	trans *transformer
+}
+
+func (tf Transform) Type() reflect.Type             { return tf.typ }
+func (tf Transform) Values() (vx, vy reflect.Value) { return tf.vx, tf.vy }
+func (tf Transform) String() string                 { return fmt.Sprintf("%s()", tf.trans.name) }
+
+// Name is the name of the [Transformer].
+func (tf Transform) Name() string { return tf.trans.name }
+
+// Func is the function pointer to the transformer function.
+func (tf Transform) Func() reflect.Value { return tf.trans.fnc }
+
+// Option returns the originally constructed [Transformer] option.
+// The == operator can be used to detect the exact option used.
+func (tf Transform) Option() Option { return tf.trans }
+
+// pointerPath represents a dual-stack of pointers encountered when
+// recursively traversing the x and y values. This data structure supports
+// detection of cycles and determining whether the cycles are equal.
+// In Go, cycles can occur via pointers, slices, and maps.
+//
+// The pointerPath uses a map to represent a stack; where descension into a
+// pointer pushes the address onto the stack, and ascension from a pointer
+// pops the address from the stack. Thus, when traversing into a pointer from
+// reflect.Ptr, reflect.Slice element, or reflect.Map, we can detect cycles
+// by checking whether the pointer has already been visited. The cycle detection
+// uses a separate stack for the x and y values.
+//
+// If a cycle is detected we need to determine whether the two pointers
+// should be considered equal. The definition of equality chosen by Equal
+// requires two graphs to have the same structure. To determine this, both the
+// x and y values must have a cycle where the previous pointers were also
+// encountered together as a pair.
+//
+// Semantically, this is equivalent to augmenting Indirect, SliceIndex, and
+// MapIndex with pointer information for the x and y values.
+// Suppose px and py are two pointers to compare, we then search the
+// Path for whether px was ever encountered in the Path history of x, and
+// similarly so with py. If either side has a cycle, the comparison is only
+// equal if both px and py have a cycle resulting from the same PathStep.
+//
+// Using a map as a stack is more performant as we can perform cycle detection
+// in O(1) instead of O(N) where N is len(Path).
+type pointerPath struct {
+	// mx is keyed by x pointers, where the value is the associated y pointer.
+	mx map[value.Pointer]value.Pointer
+	// my is keyed by y pointers, where the value is the associated x pointer.
+	my map[value.Pointer]value.Pointer
+}
+
+func (p *pointerPath) Init() {
+	p.mx = make(map[value.Pointer]value.Pointer)
+	p.my = make(map[value.Pointer]value.Pointer)
+}
+
+// Push indicates intent to descend into pointers vx and vy where
+// visited reports whether either has been seen before. If visited before,
+// equal reports whether both pointers were encountered together.
+// Pop must be called if and only if the pointers were never visited.
+//
+// The pointers vx and vy must be a reflect.Ptr, reflect.Slice, or reflect.Map
+// and be non-nil.
+func (p pointerPath) Push(vx, vy reflect.Value) (equal, visited bool) {
+	px := value.PointerOf(vx)
+	py := value.PointerOf(vy)
+	_, ok1 := p.mx[px]
+	_, ok2 := p.my[py]
+	if ok1 || ok2 {
+		equal = p.mx[px] == py && p.my[py] == px // Pointers paired together
+		return equal, true
+	}
+	p.mx[px] = py
+	p.my[py] = px
+	return false, false
+}
+
+// Pop ascends from pointers vx and vy.
+func (p pointerPath) Pop(vx, vy reflect.Value) {
+	delete(p.mx, value.PointerOf(vx))
+	delete(p.my, value.PointerOf(vy))
+}
+
+// isExported reports whether the identifier is exported.
+func isExported(id string) bool {
+	r, _ := utf8.DecodeRuneInString(id)
+	return unicode.IsUpper(r)
+}

vendor/github.com/google/go-cmp/cmp/report.go

@@ -0,0 +1,54 @@
+// Copyright 2017, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+// defaultReporter implements the reporter interface.
+//
+// As Equal serially calls the PushStep, Report, and PopStep methods, the
+// defaultReporter constructs a tree-based representation of the compared value
+// and the result of each comparison (see valueNode).
+//
+// When the String method is called, the FormatDiff method transforms the
+// valueNode tree into a textNode tree, which is a tree-based representation
+// of the textual output (see textNode).
+//
+// Lastly, the textNode.String method produces the final report as a string.
+type defaultReporter struct {
+	root *valueNode
+	curr *valueNode
+}
+
+func (r *defaultReporter) PushStep(ps PathStep) {
+	r.curr = r.curr.PushStep(ps)
+	if r.root == nil {
+		r.root = r.curr
+	}
+}
+func (r *defaultReporter) Report(rs Result) {
+	r.curr.Report(rs)
+}
+func (r *defaultReporter) PopStep() {
+	r.curr = r.curr.PopStep()
+}
+
+// String provides a full report of the differences detected as a structured
+// literal in pseudo-Go syntax. String may only be called after the entire tree
+// has been traversed.
+func (r *defaultReporter) String() string {
+	assert(r.root != nil && r.curr == nil)
+	if r.root.NumDiff == 0 {
+		return ""
+	}
+	ptrs := new(pointerReferences)
+	text := formatOptions{}.FormatDiff(r.root, ptrs)
+	resolveReferences(text)
+	return text.String()
+}
+
+func assert(ok bool) {
+	if !ok {
+		panic("assertion failure")
+	}
+}

vendor/github.com/google/go-cmp/cmp/report_compare.go

@@ -0,0 +1,433 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+)
+
+// numContextRecords is the number of surrounding equal records to print.
+const numContextRecords = 2
+
+type diffMode byte
+
+const (
+	diffUnknown   diffMode = 0
+	diffIdentical diffMode = ' '
+	diffRemoved   diffMode = '-'
+	diffInserted  diffMode = '+'
+)
+
+type typeMode int
+
+const (
+	// emitType always prints the type.
+	emitType typeMode = iota
+	// elideType never prints the type.
+	elideType
+	// autoType prints the type only for composite kinds
+	// (i.e., structs, slices, arrays, and maps).
+	autoType
+)
+
+type formatOptions struct {
+	// DiffMode controls the output mode of FormatDiff.
+	//
+	// If diffUnknown,   then produce a diff of the x and y values.
+	// If diffIdentical, then emit values as if they were equal.
+	// If diffRemoved,   then only emit x values (ignoring y values).
+	// If diffInserted,  then only emit y values (ignoring x values).
+	DiffMode diffMode
+
+	// TypeMode controls whether to print the type for the current node.
+	//
+	// As a general rule of thumb, we always print the type of the next node
+	// after an interface, and always elide the type of the next node after
+	// a slice or map node.
+	TypeMode typeMode
+
+	// formatValueOptions are options specific to printing reflect.Values.
+	formatValueOptions
+}
+
+func (opts formatOptions) WithDiffMode(d diffMode) formatOptions {
+	opts.DiffMode = d
+	return opts
+}
+func (opts formatOptions) WithTypeMode(t typeMode) formatOptions {
+	opts.TypeMode = t
+	return opts
+}
+func (opts formatOptions) WithVerbosity(level int) formatOptions {
+	opts.VerbosityLevel = level
+	opts.LimitVerbosity = true
+	return opts
+}
+func (opts formatOptions) verbosity() uint {
+	switch {
+	case opts.VerbosityLevel < 0:
+		return 0
+	case opts.VerbosityLevel > 16:
+		return 16 // some reasonable maximum to avoid shift overflow
+	default:
+		return uint(opts.VerbosityLevel)
+	}
+}
+
+const maxVerbosityPreset = 6
+
+// verbosityPreset modifies the verbosity settings given an index
+// between 0 and maxVerbosityPreset, inclusive.
+func verbosityPreset(opts formatOptions, i int) formatOptions {
+	opts.VerbosityLevel = int(opts.verbosity()) + 2*i
+	if i > 0 {
+		opts.AvoidStringer = true
+	}
+	if i >= maxVerbosityPreset {
+		opts.PrintAddresses = true
+		opts.QualifiedNames = true
+	}
+	return opts
+}
+
+// FormatDiff converts a valueNode tree into a textNode tree, where the later
+// is a textual representation of the differences detected in the former.
+func (opts formatOptions) FormatDiff(v *valueNode, ptrs *pointerReferences) (out textNode) {
+	if opts.DiffMode == diffIdentical {
+		opts = opts.WithVerbosity(1)
+	} else if opts.verbosity() < 3 {
+		opts = opts.WithVerbosity(3)
+	}
+
+	// Check whether we have specialized formatting for this node.
+	// This is not necessary, but helpful for producing more readable outputs.
+	if opts.CanFormatDiffSlice(v) {
+		return opts.FormatDiffSlice(v)
+	}
+
+	var parentKind reflect.Kind
+	if v.parent != nil && v.parent.TransformerName == "" {
+		parentKind = v.parent.Type.Kind()
+	}
+
+	// For leaf nodes, format the value based on the reflect.Values alone.
+	// As a special case, treat equal []byte as a leaf nodes.
+	isBytes := v.Type.Kind() == reflect.Slice && v.Type.Elem() == byteType
+	isEqualBytes := isBytes && v.NumDiff+v.NumIgnored+v.NumTransformed == 0
+	if v.MaxDepth == 0 || isEqualBytes {
+		switch opts.DiffMode {
+		case diffUnknown, diffIdentical:
+			// Format Equal.
+			if v.NumDiff == 0 {
+				outx := opts.FormatValue(v.ValueX, parentKind, ptrs)
+				outy := opts.FormatValue(v.ValueY, parentKind, ptrs)
+				if v.NumIgnored > 0 && v.NumSame == 0 {
+					return textEllipsis
+				} else if outx.Len() < outy.Len() {
+					return outx
+				} else {
+					return outy
+				}
+			}
+
+			// Format unequal.
+			assert(opts.DiffMode == diffUnknown)
+			var list textList
+			outx := opts.WithTypeMode(elideType).FormatValue(v.ValueX, parentKind, ptrs)
+			outy := opts.WithTypeMode(elideType).FormatValue(v.ValueY, parentKind, ptrs)
+			for i := 0; i <= maxVerbosityPreset && outx != nil && outy != nil && outx.Equal(outy); i++ {
+				opts2 := verbosityPreset(opts, i).WithTypeMode(elideType)
+				outx = opts2.FormatValue(v.ValueX, parentKind, ptrs)
+				outy = opts2.FormatValue(v.ValueY, parentKind, ptrs)
+			}
+			if outx != nil {
+				list = append(list, textRecord{Diff: '-', Value: outx})
+			}
+			if outy != nil {
+				list = append(list, textRecord{Diff: '+', Value: outy})
+			}
+			return opts.WithTypeMode(emitType).FormatType(v.Type, list)
+		case diffRemoved:
+			return opts.FormatValue(v.ValueX, parentKind, ptrs)
+		case diffInserted:
+			return opts.FormatValue(v.ValueY, parentKind, ptrs)
+		default:
+			panic("invalid diff mode")
+		}
+	}
+
+	// Register slice element to support cycle detection.
+	if parentKind == reflect.Slice {
+		ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, true)
+		defer ptrs.Pop()
+		defer func() { out = wrapTrunkReferences(ptrRefs, out) }()
+	}
+
+	// Descend into the child value node.
+	if v.TransformerName != "" {
+		out := opts.WithTypeMode(emitType).FormatDiff(v.Value, ptrs)
+		out = &textWrap{Prefix: "Inverse(" + v.TransformerName + ", ", Value: out, Suffix: ")"}
+		return opts.FormatType(v.Type, out)
+	} else {
+		switch k := v.Type.Kind(); k {
+		case reflect.Struct, reflect.Array, reflect.Slice:
+			out = opts.formatDiffList(v.Records, k, ptrs)
+			out = opts.FormatType(v.Type, out)
+		case reflect.Map:
+			// Register map to support cycle detection.
+			ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, false)
+			defer ptrs.Pop()
+
+			out = opts.formatDiffList(v.Records, k, ptrs)
+			out = wrapTrunkReferences(ptrRefs, out)
+			out = opts.FormatType(v.Type, out)
+		case reflect.Ptr:
+			// Register pointer to support cycle detection.
+			ptrRefs := ptrs.PushPair(v.ValueX, v.ValueY, opts.DiffMode, false)
+			defer ptrs.Pop()
+
+			out = opts.FormatDiff(v.Value, ptrs)
+			out = wrapTrunkReferences(ptrRefs, out)
+			out = &textWrap{Prefix: "&", Value: out}
+		case reflect.Interface:
+			out = opts.WithTypeMode(emitType).FormatDiff(v.Value, ptrs)
+		default:
+			panic(fmt.Sprintf("%v cannot have children", k))
+		}
+		return out
+	}
+}
+
+func (opts formatOptions) formatDiffList(recs []reportRecord, k reflect.Kind, ptrs *pointerReferences) textNode {
+	// Derive record name based on the data structure kind.
+	var name string
+	var formatKey func(reflect.Value) string
+	switch k {
+	case reflect.Struct:
+		name = "field"
+		opts = opts.WithTypeMode(autoType)
+		formatKey = func(v reflect.Value) string { return v.String() }
+	case reflect.Slice, reflect.Array:
+		name = "element"
+		opts = opts.WithTypeMode(elideType)
+		formatKey = func(reflect.Value) string { return "" }
+	case reflect.Map:
+		name = "entry"
+		opts = opts.WithTypeMode(elideType)
+		formatKey = func(v reflect.Value) string { return formatMapKey(v, false, ptrs) }
+	}
+
+	maxLen := -1
+	if opts.LimitVerbosity {
+		if opts.DiffMode == diffIdentical {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+		} else {
+			maxLen = (1 << opts.verbosity()) << 1 // 2, 4, 8, 16, 32, 64, etc...
+		}
+		opts.VerbosityLevel--
+	}
+
+	// Handle unification.
+	switch opts.DiffMode {
+	case diffIdentical, diffRemoved, diffInserted:
+		var list textList
+		var deferredEllipsis bool // Add final "..." to indicate records were dropped
+		for _, r := range recs {
+			if len(list) == maxLen {
+				deferredEllipsis = true
+				break
+			}
+
+			// Elide struct fields that are zero value.
+			if k == reflect.Struct {
+				var isZero bool
+				switch opts.DiffMode {
+				case diffIdentical:
+					isZero = r.Value.ValueX.IsZero() || r.Value.ValueY.IsZero()
+				case diffRemoved:
+					isZero = r.Value.ValueX.IsZero()
+				case diffInserted:
+					isZero = r.Value.ValueY.IsZero()
+				}
+				if isZero {
+					continue
+				}
+			}
+			// Elide ignored nodes.
+			if r.Value.NumIgnored > 0 && r.Value.NumSame+r.Value.NumDiff == 0 {
+				deferredEllipsis = !(k == reflect.Slice || k == reflect.Array)
+				if !deferredEllipsis {
+					list.AppendEllipsis(diffStats{})
+				}
+				continue
+			}
+			if out := opts.FormatDiff(r.Value, ptrs); out != nil {
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+			}
+		}
+		if deferredEllipsis {
+			list.AppendEllipsis(diffStats{})
+		}
+		return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	case diffUnknown:
+	default:
+		panic("invalid diff mode")
+	}
+
+	// Handle differencing.
+	var numDiffs int
+	var list textList
+	var keys []reflect.Value // invariant: len(list) == len(keys)
+	groups := coalesceAdjacentRecords(name, recs)
+	maxGroup := diffStats{Name: name}
+	for i, ds := range groups {
+		if maxLen >= 0 && numDiffs >= maxLen {
+			maxGroup = maxGroup.Append(ds)
+			continue
+		}
+
+		// Handle equal records.
+		if ds.NumDiff() == 0 {
+			// Compute the number of leading and trailing records to print.
+			var numLo, numHi int
+			numEqual := ds.NumIgnored + ds.NumIdentical
+			for numLo < numContextRecords && numLo+numHi < numEqual && i != 0 {
+				if r := recs[numLo].Value; r.NumIgnored > 0 && r.NumSame+r.NumDiff == 0 {
+					break
+				}
+				numLo++
+			}
+			for numHi < numContextRecords && numLo+numHi < numEqual && i != len(groups)-1 {
+				if r := recs[numEqual-numHi-1].Value; r.NumIgnored > 0 && r.NumSame+r.NumDiff == 0 {
+					break
+				}
+				numHi++
+			}
+			if numEqual-(numLo+numHi) == 1 && ds.NumIgnored == 0 {
+				numHi++ // Avoid pointless coalescing of a single equal record
+			}
+
+			// Format the equal values.
+			for _, r := range recs[:numLo] {
+				out := opts.WithDiffMode(diffIdentical).FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+			if numEqual > numLo+numHi {
+				ds.NumIdentical -= numLo + numHi
+				list.AppendEllipsis(ds)
+				for len(keys) < len(list) {
+					keys = append(keys, reflect.Value{})
+				}
+			}
+			for _, r := range recs[numEqual-numHi : numEqual] {
+				out := opts.WithDiffMode(diffIdentical).FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+			recs = recs[numEqual:]
+			continue
+		}
+
+		// Handle unequal records.
+		for _, r := range recs[:ds.NumDiff()] {
+			switch {
+			case opts.CanFormatDiffSlice(r.Value):
+				out := opts.FormatDiffSlice(r.Value)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			case r.Value.NumChildren == r.Value.MaxDepth:
+				outx := opts.WithDiffMode(diffRemoved).FormatDiff(r.Value, ptrs)
+				outy := opts.WithDiffMode(diffInserted).FormatDiff(r.Value, ptrs)
+				for i := 0; i <= maxVerbosityPreset && outx != nil && outy != nil && outx.Equal(outy); i++ {
+					opts2 := verbosityPreset(opts, i)
+					outx = opts2.WithDiffMode(diffRemoved).FormatDiff(r.Value, ptrs)
+					outy = opts2.WithDiffMode(diffInserted).FormatDiff(r.Value, ptrs)
+				}
+				if outx != nil {
+					list = append(list, textRecord{Diff: diffRemoved, Key: formatKey(r.Key), Value: outx})
+					keys = append(keys, r.Key)
+				}
+				if outy != nil {
+					list = append(list, textRecord{Diff: diffInserted, Key: formatKey(r.Key), Value: outy})
+					keys = append(keys, r.Key)
+				}
+			default:
+				out := opts.FormatDiff(r.Value, ptrs)
+				list = append(list, textRecord{Key: formatKey(r.Key), Value: out})
+				keys = append(keys, r.Key)
+			}
+		}
+		recs = recs[ds.NumDiff():]
+		numDiffs += ds.NumDiff()
+	}
+	if maxGroup.IsZero() {
+		assert(len(recs) == 0)
+	} else {
+		list.AppendEllipsis(maxGroup)
+		for len(keys) < len(list) {
+			keys = append(keys, reflect.Value{})
+		}
+	}
+	assert(len(list) == len(keys))
+
+	// For maps, the default formatting logic uses fmt.Stringer which may
+	// produce ambiguous output. Avoid calling String to disambiguate.
+	if k == reflect.Map {
+		var ambiguous bool
+		seenKeys := map[string]reflect.Value{}
+		for i, currKey := range keys {
+			if currKey.IsValid() {
+				strKey := list[i].Key
+				prevKey, seen := seenKeys[strKey]
+				if seen && prevKey.CanInterface() && currKey.CanInterface() {
+					ambiguous = prevKey.Interface() != currKey.Interface()
+					if ambiguous {
+						break
+					}
+				}
+				seenKeys[strKey] = currKey
+			}
+		}
+		if ambiguous {
+			for i, k := range keys {
+				if k.IsValid() {
+					list[i].Key = formatMapKey(k, true, ptrs)
+				}
+			}
+		}
+	}
+
+	return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+}
+
+// coalesceAdjacentRecords coalesces the list of records into groups of
+// adjacent equal, or unequal counts.
+func coalesceAdjacentRecords(name string, recs []reportRecord) (groups []diffStats) {
+	var prevCase int // Arbitrary index into which case last occurred
+	lastStats := func(i int) *diffStats {
+		if prevCase != i {
+			groups = append(groups, diffStats{Name: name})
+			prevCase = i
+		}
+		return &groups[len(groups)-1]
+	}
+	for _, r := range recs {
+		switch rv := r.Value; {
+		case rv.NumIgnored > 0 && rv.NumSame+rv.NumDiff == 0:
+			lastStats(1).NumIgnored++
+		case rv.NumDiff == 0:
+			lastStats(1).NumIdentical++
+		case rv.NumDiff > 0 && !rv.ValueY.IsValid():
+			lastStats(2).NumRemoved++
+		case rv.NumDiff > 0 && !rv.ValueX.IsValid():
+			lastStats(2).NumInserted++
+		default:
+			lastStats(2).NumModified++
+		}
+	}
+	return groups
+}

vendor/github.com/google/go-cmp/cmp/report_references.go

@@ -0,0 +1,264 @@
+// Copyright 2020, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+const (
+	pointerDelimPrefix = "⟪"
+	pointerDelimSuffix = "⟫"
+)
+
+// formatPointer prints the address of the pointer.
+func formatPointer(p value.Pointer, withDelims bool) string {
+	v := p.Uintptr()
+	if flags.Deterministic {
+		v = 0xdeadf00f // Only used for stable testing purposes
+	}
+	if withDelims {
+		return pointerDelimPrefix + formatHex(uint64(v)) + pointerDelimSuffix
+	}
+	return formatHex(uint64(v))
+}
+
+// pointerReferences is a stack of pointers visited so far.
+type pointerReferences [][2]value.Pointer
+
+func (ps *pointerReferences) PushPair(vx, vy reflect.Value, d diffMode, deref bool) (pp [2]value.Pointer) {
+	if deref && vx.IsValid() {
+		vx = vx.Addr()
+	}
+	if deref && vy.IsValid() {
+		vy = vy.Addr()
+	}
+	switch d {
+	case diffUnknown, diffIdentical:
+		pp = [2]value.Pointer{value.PointerOf(vx), value.PointerOf(vy)}
+	case diffRemoved:
+		pp = [2]value.Pointer{value.PointerOf(vx), value.Pointer{}}
+	case diffInserted:
+		pp = [2]value.Pointer{value.Pointer{}, value.PointerOf(vy)}
+	}
+	*ps = append(*ps, pp)
+	return pp
+}
+
+func (ps *pointerReferences) Push(v reflect.Value) (p value.Pointer, seen bool) {
+	p = value.PointerOf(v)
+	for _, pp := range *ps {
+		if p == pp[0] || p == pp[1] {
+			return p, true
+		}
+	}
+	*ps = append(*ps, [2]value.Pointer{p, p})
+	return p, false
+}
+
+func (ps *pointerReferences) Pop() {
+	*ps = (*ps)[:len(*ps)-1]
+}
+
+// trunkReferences is metadata for a textNode indicating that the sub-tree
+// represents the value for either pointer in a pair of references.
+type trunkReferences struct{ pp [2]value.Pointer }
+
+// trunkReference is metadata for a textNode indicating that the sub-tree
+// represents the value for the given pointer reference.
+type trunkReference struct{ p value.Pointer }
+
+// leafReference is metadata for a textNode indicating that the value is
+// truncated as it refers to another part of the tree (i.e., a trunk).
+type leafReference struct{ p value.Pointer }
+
+func wrapTrunkReferences(pp [2]value.Pointer, s textNode) textNode {
+	switch {
+	case pp[0].IsNil():
+		return &textWrap{Value: s, Metadata: trunkReference{pp[1]}}
+	case pp[1].IsNil():
+		return &textWrap{Value: s, Metadata: trunkReference{pp[0]}}
+	case pp[0] == pp[1]:
+		return &textWrap{Value: s, Metadata: trunkReference{pp[0]}}
+	default:
+		return &textWrap{Value: s, Metadata: trunkReferences{pp}}
+	}
+}
+func wrapTrunkReference(p value.Pointer, printAddress bool, s textNode) textNode {
+	var prefix string
+	if printAddress {
+		prefix = formatPointer(p, true)
+	}
+	return &textWrap{Prefix: prefix, Value: s, Metadata: trunkReference{p}}
+}
+func makeLeafReference(p value.Pointer, printAddress bool) textNode {
+	out := &textWrap{Prefix: "(", Value: textEllipsis, Suffix: ")"}
+	var prefix string
+	if printAddress {
+		prefix = formatPointer(p, true)
+	}
+	return &textWrap{Prefix: prefix, Value: out, Metadata: leafReference{p}}
+}
+
+// resolveReferences walks the textNode tree searching for any leaf reference
+// metadata and resolves each against the corresponding trunk references.
+// Since pointer addresses in memory are not particularly readable to the user,
+// it replaces each pointer value with an arbitrary and unique reference ID.
+func resolveReferences(s textNode) {
+	var walkNodes func(textNode, func(textNode))
+	walkNodes = func(s textNode, f func(textNode)) {
+		f(s)
+		switch s := s.(type) {
+		case *textWrap:
+			walkNodes(s.Value, f)
+		case textList:
+			for _, r := range s {
+				walkNodes(r.Value, f)
+			}
+		}
+	}
+
+	// Collect all trunks and leaves with reference metadata.
+	var trunks, leaves []*textWrap
+	walkNodes(s, func(s textNode) {
+		if s, ok := s.(*textWrap); ok {
+			switch s.Metadata.(type) {
+			case leafReference:
+				leaves = append(leaves, s)
+			case trunkReference, trunkReferences:
+				trunks = append(trunks, s)
+			}
+		}
+	})
+
+	// No leaf references to resolve.
+	if len(leaves) == 0 {
+		return
+	}
+
+	// Collect the set of all leaf references to resolve.
+	leafPtrs := make(map[value.Pointer]bool)
+	for _, leaf := range leaves {
+		leafPtrs[leaf.Metadata.(leafReference).p] = true
+	}
+
+	// Collect the set of trunk pointers that are always paired together.
+	// This allows us to assign a single ID to both pointers for brevity.
+	// If a pointer in a pair ever occurs by itself or as a different pair,
+	// then the pair is broken.
+	pairedTrunkPtrs := make(map[value.Pointer]value.Pointer)
+	unpair := func(p value.Pointer) {
+		if !pairedTrunkPtrs[p].IsNil() {
+			pairedTrunkPtrs[pairedTrunkPtrs[p]] = value.Pointer{} // invalidate other half
+		}
+		pairedTrunkPtrs[p] = value.Pointer{} // invalidate this half
+	}
+	for _, trunk := range trunks {
+		switch p := trunk.Metadata.(type) {
+		case trunkReference:
+			unpair(p.p) // standalone pointer cannot be part of a pair
+		case trunkReferences:
+			p0, ok0 := pairedTrunkPtrs[p.pp[0]]
+			p1, ok1 := pairedTrunkPtrs[p.pp[1]]
+			switch {
+			case !ok0 && !ok1:
+				// Register the newly seen pair.
+				pairedTrunkPtrs[p.pp[0]] = p.pp[1]
+				pairedTrunkPtrs[p.pp[1]] = p.pp[0]
+			case ok0 && ok1 && p0 == p.pp[1] && p1 == p.pp[0]:
+				// Exact pair already seen; do nothing.
+			default:
+				// Pair conflicts with some other pair; break all pairs.
+				unpair(p.pp[0])
+				unpair(p.pp[1])
+			}
+		}
+	}
+
+	// Correlate each pointer referenced by leaves to a unique identifier,
+	// and print the IDs for each trunk that matches those pointers.
+	var nextID uint
+	ptrIDs := make(map[value.Pointer]uint)
+	newID := func() uint {
+		id := nextID
+		nextID++
+		return id
+	}
+	for _, trunk := range trunks {
+		switch p := trunk.Metadata.(type) {
+		case trunkReference:
+			if print := leafPtrs[p.p]; print {
+				id, ok := ptrIDs[p.p]
+				if !ok {
+					id = newID()
+					ptrIDs[p.p] = id
+				}
+				trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id))
+			}
+		case trunkReferences:
+			print0 := leafPtrs[p.pp[0]]
+			print1 := leafPtrs[p.pp[1]]
+			if print0 || print1 {
+				id0, ok0 := ptrIDs[p.pp[0]]
+				id1, ok1 := ptrIDs[p.pp[1]]
+				isPair := pairedTrunkPtrs[p.pp[0]] == p.pp[1] && pairedTrunkPtrs[p.pp[1]] == p.pp[0]
+				if isPair {
+					var id uint
+					assert(ok0 == ok1) // must be seen together or not at all
+					if ok0 {
+						assert(id0 == id1) // must have the same ID
+						id = id0
+					} else {
+						id = newID()
+						ptrIDs[p.pp[0]] = id
+						ptrIDs[p.pp[1]] = id
+					}
+					trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id))
+				} else {
+					if print0 && !ok0 {
+						id0 = newID()
+						ptrIDs[p.pp[0]] = id0
+					}
+					if print1 && !ok1 {
+						id1 = newID()
+						ptrIDs[p.pp[1]] = id1
+					}
+					switch {
+					case print0 && print1:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id0)+","+formatReference(id1))
+					case print0:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id0))
+					case print1:
+						trunk.Prefix = updateReferencePrefix(trunk.Prefix, formatReference(id1))
+					}
+				}
+			}
+		}
+	}
+
+	// Update all leaf references with the unique identifier.
+	for _, leaf := range leaves {
+		if id, ok := ptrIDs[leaf.Metadata.(leafReference).p]; ok {
+			leaf.Prefix = updateReferencePrefix(leaf.Prefix, formatReference(id))
+		}
+	}
+}
+
+func formatReference(id uint) string {
+	return fmt.Sprintf("ref#%d", id)
+}
+
+func updateReferencePrefix(prefix, ref string) string {
+	if prefix == "" {
+		return pointerDelimPrefix + ref + pointerDelimSuffix
+	}
+	suffix := strings.TrimPrefix(prefix, pointerDelimPrefix)
+	return pointerDelimPrefix + ref + ": " + suffix
+}

vendor/github.com/google/go-cmp/cmp/report_reflect.go

@@ -0,0 +1,414 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/value"
+)
+
+var (
+	anyType    = reflect.TypeOf((*interface{})(nil)).Elem()
+	stringType = reflect.TypeOf((*string)(nil)).Elem()
+	bytesType  = reflect.TypeOf((*[]byte)(nil)).Elem()
+	byteType   = reflect.TypeOf((*byte)(nil)).Elem()
+)
+
+type formatValueOptions struct {
+	// AvoidStringer controls whether to avoid calling custom stringer
+	// methods like error.Error or fmt.Stringer.String.
+	AvoidStringer bool
+
+	// PrintAddresses controls whether to print the address of all pointers,
+	// slice elements, and maps.
+	PrintAddresses bool
+
+	// QualifiedNames controls whether FormatType uses the fully qualified name
+	// (including the full package path as opposed to just the package name).
+	QualifiedNames bool
+
+	// VerbosityLevel controls the amount of output to produce.
+	// A higher value produces more output. A value of zero or lower produces
+	// no output (represented using an ellipsis).
+	// If LimitVerbosity is false, then the level is treated as infinite.
+	VerbosityLevel int
+
+	// LimitVerbosity specifies that formatting should respect VerbosityLevel.
+	LimitVerbosity bool
+}
+
+// FormatType prints the type as if it were wrapping s.
+// This may return s as-is depending on the current type and TypeMode mode.
+func (opts formatOptions) FormatType(t reflect.Type, s textNode) textNode {
+	// Check whether to emit the type or not.
+	switch opts.TypeMode {
+	case autoType:
+		switch t.Kind() {
+		case reflect.Struct, reflect.Slice, reflect.Array, reflect.Map:
+			if s.Equal(textNil) {
+				return s
+			}
+		default:
+			return s
+		}
+		if opts.DiffMode == diffIdentical {
+			return s // elide type for identical nodes
+		}
+	case elideType:
+		return s
+	}
+
+	// Determine the type label, applying special handling for unnamed types.
+	typeName := value.TypeString(t, opts.QualifiedNames)
+	if t.Name() == "" {
+		// According to Go grammar, certain type literals contain symbols that
+		// do not strongly bind to the next lexicographical token (e.g., *T).
+		switch t.Kind() {
+		case reflect.Chan, reflect.Func, reflect.Ptr:
+			typeName = "(" + typeName + ")"
+		}
+	}
+	return &textWrap{Prefix: typeName, Value: wrapParens(s)}
+}
+
+// wrapParens wraps s with a set of parenthesis, but avoids it if the
+// wrapped node itself is already surrounded by a pair of parenthesis or braces.
+// It handles unwrapping one level of pointer-reference nodes.
+func wrapParens(s textNode) textNode {
+	var refNode *textWrap
+	if s2, ok := s.(*textWrap); ok {
+		// Unwrap a single pointer reference node.
+		switch s2.Metadata.(type) {
+		case leafReference, trunkReference, trunkReferences:
+			refNode = s2
+			if s3, ok := refNode.Value.(*textWrap); ok {
+				s2 = s3
+			}
+		}
+
+		// Already has delimiters that make parenthesis unnecessary.
+		hasParens := strings.HasPrefix(s2.Prefix, "(") && strings.HasSuffix(s2.Suffix, ")")
+		hasBraces := strings.HasPrefix(s2.Prefix, "{") && strings.HasSuffix(s2.Suffix, "}")
+		if hasParens || hasBraces {
+			return s
+		}
+	}
+	if refNode != nil {
+		refNode.Value = &textWrap{Prefix: "(", Value: refNode.Value, Suffix: ")"}
+		return s
+	}
+	return &textWrap{Prefix: "(", Value: s, Suffix: ")"}
+}
+
+// FormatValue prints the reflect.Value, taking extra care to avoid descending
+// into pointers already in ptrs. As pointers are visited, ptrs is also updated.
+func (opts formatOptions) FormatValue(v reflect.Value, parentKind reflect.Kind, ptrs *pointerReferences) (out textNode) {
+	if !v.IsValid() {
+		return nil
+	}
+	t := v.Type()
+
+	// Check slice element for cycles.
+	if parentKind == reflect.Slice {
+		ptrRef, visited := ptrs.Push(v.Addr())
+		if visited {
+			return makeLeafReference(ptrRef, false)
+		}
+		defer ptrs.Pop()
+		defer func() { out = wrapTrunkReference(ptrRef, false, out) }()
+	}
+
+	// Check whether there is an Error or String method to call.
+	if !opts.AvoidStringer && v.CanInterface() {
+		// Avoid calling Error or String methods on nil receivers since many
+		// implementations crash when doing so.
+		if (t.Kind() != reflect.Ptr && t.Kind() != reflect.Interface) || !v.IsNil() {
+			var prefix, strVal string
+			func() {
+				// Swallow and ignore any panics from String or Error.
+				defer func() { recover() }()
+				switch v := v.Interface().(type) {
+				case error:
+					strVal = v.Error()
+					prefix = "e"
+				case fmt.Stringer:
+					strVal = v.String()
+					prefix = "s"
+				}
+			}()
+			if prefix != "" {
+				return opts.formatString(prefix, strVal)
+			}
+		}
+	}
+
+	// Check whether to explicitly wrap the result with the type.
+	var skipType bool
+	defer func() {
+		if !skipType {
+			out = opts.FormatType(t, out)
+		}
+	}()
+
+	switch t.Kind() {
+	case reflect.Bool:
+		return textLine(fmt.Sprint(v.Bool()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return textLine(fmt.Sprint(v.Int()))
+	case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return textLine(fmt.Sprint(v.Uint()))
+	case reflect.Uint8:
+		if parentKind == reflect.Slice || parentKind == reflect.Array {
+			return textLine(formatHex(v.Uint()))
+		}
+		return textLine(fmt.Sprint(v.Uint()))
+	case reflect.Uintptr:
+		return textLine(formatHex(v.Uint()))
+	case reflect.Float32, reflect.Float64:
+		return textLine(fmt.Sprint(v.Float()))
+	case reflect.Complex64, reflect.Complex128:
+		return textLine(fmt.Sprint(v.Complex()))
+	case reflect.String:
+		return opts.formatString("", v.String())
+	case reflect.UnsafePointer, reflect.Chan, reflect.Func:
+		return textLine(formatPointer(value.PointerOf(v), true))
+	case reflect.Struct:
+		var list textList
+		v := makeAddressable(v) // needed for retrieveUnexportedField
+		maxLen := v.NumField()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		for i := 0; i < v.NumField(); i++ {
+			vv := v.Field(i)
+			if vv.IsZero() {
+				continue // Elide fields with zero values
+			}
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			sf := t.Field(i)
+			if !isExported(sf.Name) {
+				vv = retrieveUnexportedField(v, sf, true)
+			}
+			s := opts.WithTypeMode(autoType).FormatValue(vv, t.Kind(), ptrs)
+			list = append(list, textRecord{Key: sf.Name, Value: s})
+		}
+		return &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	case reflect.Slice:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check whether this is a []byte of text data.
+		if t.Elem() == byteType {
+			b := v.Bytes()
+			isPrintSpace := func(r rune) bool { return unicode.IsPrint(r) || unicode.IsSpace(r) }
+			if len(b) > 0 && utf8.Valid(b) && len(bytes.TrimFunc(b, isPrintSpace)) == 0 {
+				out = opts.formatString("", string(b))
+				skipType = true
+				return opts.FormatType(t, out)
+			}
+		}
+
+		fallthrough
+	case reflect.Array:
+		maxLen := v.Len()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		var list textList
+		for i := 0; i < v.Len(); i++ {
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			s := opts.WithTypeMode(elideType).FormatValue(v.Index(i), t.Kind(), ptrs)
+			list = append(list, textRecord{Value: s})
+		}
+
+		out = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+		if t.Kind() == reflect.Slice && opts.PrintAddresses {
+			header := fmt.Sprintf("ptr:%v, len:%d, cap:%d", formatPointer(value.PointerOf(v), false), v.Len(), v.Cap())
+			out = &textWrap{Prefix: pointerDelimPrefix + header + pointerDelimSuffix, Value: out}
+		}
+		return out
+	case reflect.Map:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check pointer for cycles.
+		ptrRef, visited := ptrs.Push(v)
+		if visited {
+			return makeLeafReference(ptrRef, opts.PrintAddresses)
+		}
+		defer ptrs.Pop()
+
+		maxLen := v.Len()
+		if opts.LimitVerbosity {
+			maxLen = ((1 << opts.verbosity()) >> 1) << 2 // 0, 4, 8, 16, 32, etc...
+			opts.VerbosityLevel--
+		}
+		var list textList
+		for _, k := range value.SortKeys(v.MapKeys()) {
+			if len(list) == maxLen {
+				list.AppendEllipsis(diffStats{})
+				break
+			}
+			sk := formatMapKey(k, false, ptrs)
+			sv := opts.WithTypeMode(elideType).FormatValue(v.MapIndex(k), t.Kind(), ptrs)
+			list = append(list, textRecord{Key: sk, Value: sv})
+		}
+
+		out = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+		out = wrapTrunkReference(ptrRef, opts.PrintAddresses, out)
+		return out
+	case reflect.Ptr:
+		if v.IsNil() {
+			return textNil
+		}
+
+		// Check pointer for cycles.
+		ptrRef, visited := ptrs.Push(v)
+		if visited {
+			out = makeLeafReference(ptrRef, opts.PrintAddresses)
+			return &textWrap{Prefix: "&", Value: out}
+		}
+		defer ptrs.Pop()
+
+		// Skip the name only if this is an unnamed pointer type.
+		// Otherwise taking the address of a value does not reproduce
+		// the named pointer type.
+		if v.Type().Name() == "" {
+			skipType = true // Let the underlying value print the type instead
+		}
+		out = opts.FormatValue(v.Elem(), t.Kind(), ptrs)
+		out = wrapTrunkReference(ptrRef, opts.PrintAddresses, out)
+		out = &textWrap{Prefix: "&", Value: out}
+		return out
+	case reflect.Interface:
+		if v.IsNil() {
+			return textNil
+		}
+		// Interfaces accept different concrete types,
+		// so configure the underlying value to explicitly print the type.
+		return opts.WithTypeMode(emitType).FormatValue(v.Elem(), t.Kind(), ptrs)
+	default:
+		panic(fmt.Sprintf("%v kind not handled", v.Kind()))
+	}
+}
+
+func (opts formatOptions) formatString(prefix, s string) textNode {
+	maxLen := len(s)
+	maxLines := strings.Count(s, "\n") + 1
+	if opts.LimitVerbosity {
+		maxLen = (1 << opts.verbosity()) << 5   // 32, 64, 128, 256, etc...
+		maxLines = (1 << opts.verbosity()) << 2 //  4, 8, 16, 32, 64, etc...
+	}
+
+	// For multiline strings, use the triple-quote syntax,
+	// but only use it when printing removed or inserted nodes since
+	// we only want the extra verbosity for those cases.
+	lines := strings.Split(strings.TrimSuffix(s, "\n"), "\n")
+	isTripleQuoted := len(lines) >= 4 && (opts.DiffMode == '-' || opts.DiffMode == '+')
+	for i := 0; i < len(lines) && isTripleQuoted; i++ {
+		lines[i] = strings.TrimPrefix(strings.TrimSuffix(lines[i], "\r"), "\r") // trim leading/trailing carriage returns for legacy Windows endline support
+		isPrintable := func(r rune) bool {
+			return unicode.IsPrint(r) || r == '\t' // specially treat tab as printable
+		}
+		line := lines[i]
+		isTripleQuoted = !strings.HasPrefix(strings.TrimPrefix(line, prefix), `"""`) && !strings.HasPrefix(line, "...") && strings.TrimFunc(line, isPrintable) == "" && len(line) <= maxLen
+	}
+	if isTripleQuoted {
+		var list textList
+		list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(prefix + `"""`), ElideComma: true})
+		for i, line := range lines {
+			if numElided := len(lines) - i; i == maxLines-1 && numElided > 1 {
+				comment := commentString(fmt.Sprintf("%d elided lines", numElided))
+				list = append(list, textRecord{Diff: opts.DiffMode, Value: textEllipsis, ElideComma: true, Comment: comment})
+				break
+			}
+			list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(line), ElideComma: true})
+		}
+		list = append(list, textRecord{Diff: opts.DiffMode, Value: textLine(prefix + `"""`), ElideComma: true})
+		return &textWrap{Prefix: "(", Value: list, Suffix: ")"}
+	}
+
+	// Format the string as a single-line quoted string.
+	if len(s) > maxLen+len(textEllipsis) {
+		return textLine(prefix + formatString(s[:maxLen]) + string(textEllipsis))
+	}
+	return textLine(prefix + formatString(s))
+}
+
+// formatMapKey formats v as if it were a map key.
+// The result is guaranteed to be a single line.
+func formatMapKey(v reflect.Value, disambiguate bool, ptrs *pointerReferences) string {
+	var opts formatOptions
+	opts.DiffMode = diffIdentical
+	opts.TypeMode = elideType
+	opts.PrintAddresses = disambiguate
+	opts.AvoidStringer = disambiguate
+	opts.QualifiedNames = disambiguate
+	opts.VerbosityLevel = maxVerbosityPreset
+	opts.LimitVerbosity = true
+	s := opts.FormatValue(v, reflect.Map, ptrs).String()
+	return strings.TrimSpace(s)
+}
+
+// formatString prints s as a double-quoted or backtick-quoted string.
+func formatString(s string) string {
+	// Use quoted string if it the same length as a raw string literal.
+	// Otherwise, attempt to use the raw string form.
+	qs := strconv.Quote(s)
+	if len(qs) == 1+len(s)+1 {
+		return qs
+	}
+
+	// Disallow newlines to ensure output is a single line.
+	// Only allow printable runes for readability purposes.
+	rawInvalid := func(r rune) bool {
+		return r == '`' || r == '\n' || !(unicode.IsPrint(r) || r == '\t')
+	}
+	if utf8.ValidString(s) && strings.IndexFunc(s, rawInvalid) < 0 {
+		return "`" + s + "`"
+	}
+	return qs
+}
+
+// formatHex prints u as a hexadecimal integer in Go notation.
+func formatHex(u uint64) string {
+	var f string
+	switch {
+	case u <= 0xff:
+		f = "0x%02x"
+	case u <= 0xffff:
+		f = "0x%04x"
+	case u <= 0xffffff:
+		f = "0x%06x"
+	case u <= 0xffffffff:
+		f = "0x%08x"
+	case u <= 0xffffffffff:
+		f = "0x%010x"
+	case u <= 0xffffffffffff:
+		f = "0x%012x"
+	case u <= 0xffffffffffffff:
+		f = "0x%014x"
+	case u <= 0xffffffffffffffff:
+		f = "0x%016x"
+	}
+	return fmt.Sprintf(f, u)
+}

vendor/github.com/google/go-cmp/cmp/report_slices.go

@@ -0,0 +1,614 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/diff"
+)
+
+// CanFormatDiffSlice reports whether we support custom formatting for nodes
+// that are slices of primitive kinds or strings.
+func (opts formatOptions) CanFormatDiffSlice(v *valueNode) bool {
+	switch {
+	case opts.DiffMode != diffUnknown:
+		return false // Must be formatting in diff mode
+	case v.NumDiff == 0:
+		return false // No differences detected
+	case !v.ValueX.IsValid() || !v.ValueY.IsValid():
+		return false // Both values must be valid
+	case v.NumIgnored > 0:
+		return false // Some ignore option was used
+	case v.NumTransformed > 0:
+		return false // Some transform option was used
+	case v.NumCompared > 1:
+		return false // More than one comparison was used
+	case v.NumCompared == 1 && v.Type.Name() != "":
+		// The need for cmp to check applicability of options on every element
+		// in a slice is a significant performance detriment for large []byte.
+		// The workaround is to specify Comparer(bytes.Equal),
+		// which enables cmp to compare []byte more efficiently.
+		// If they differ, we still want to provide batched diffing.
+		// The logic disallows named types since they tend to have their own
+		// String method, with nicer formatting than what this provides.
+		return false
+	}
+
+	// Check whether this is an interface with the same concrete types.
+	t := v.Type
+	vx, vy := v.ValueX, v.ValueY
+	if t.Kind() == reflect.Interface && !vx.IsNil() && !vy.IsNil() && vx.Elem().Type() == vy.Elem().Type() {
+		vx, vy = vx.Elem(), vy.Elem()
+		t = vx.Type()
+	}
+
+	// Check whether we provide specialized diffing for this type.
+	switch t.Kind() {
+	case reflect.String:
+	case reflect.Array, reflect.Slice:
+		// Only slices of primitive types have specialized handling.
+		switch t.Elem().Kind() {
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+			reflect.Bool, reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+		default:
+			return false
+		}
+
+		// Both slice values have to be non-empty.
+		if t.Kind() == reflect.Slice && (vx.Len() == 0 || vy.Len() == 0) {
+			return false
+		}
+
+		// If a sufficient number of elements already differ,
+		// use specialized formatting even if length requirement is not met.
+		if v.NumDiff > v.NumSame {
+			return true
+		}
+	default:
+		return false
+	}
+
+	// Use specialized string diffing for longer slices or strings.
+	const minLength = 32
+	return vx.Len() >= minLength && vy.Len() >= minLength
+}
+
+// FormatDiffSlice prints a diff for the slices (or strings) represented by v.
+// This provides custom-tailored logic to make printing of differences in
+// textual strings and slices of primitive kinds more readable.
+func (opts formatOptions) FormatDiffSlice(v *valueNode) textNode {
+	assert(opts.DiffMode == diffUnknown)
+	t, vx, vy := v.Type, v.ValueX, v.ValueY
+	if t.Kind() == reflect.Interface {
+		vx, vy = vx.Elem(), vy.Elem()
+		t = vx.Type()
+		opts = opts.WithTypeMode(emitType)
+	}
+
+	// Auto-detect the type of the data.
+	var sx, sy string
+	var ssx, ssy []string
+	var isString, isMostlyText, isPureLinedText, isBinary bool
+	switch {
+	case t.Kind() == reflect.String:
+		sx, sy = vx.String(), vy.String()
+		isString = true
+	case t.Kind() == reflect.Slice && t.Elem() == byteType:
+		sx, sy = string(vx.Bytes()), string(vy.Bytes())
+		isString = true
+	case t.Kind() == reflect.Array:
+		// Arrays need to be addressable for slice operations to work.
+		vx2, vy2 := reflect.New(t).Elem(), reflect.New(t).Elem()
+		vx2.Set(vx)
+		vy2.Set(vy)
+		vx, vy = vx2, vy2
+	}
+	if isString {
+		var numTotalRunes, numValidRunes, numLines, lastLineIdx, maxLineLen int
+		for i, r := range sx + sy {
+			numTotalRunes++
+			if (unicode.IsPrint(r) || unicode.IsSpace(r)) && r != utf8.RuneError {
+				numValidRunes++
+			}
+			if r == '\n' {
+				if maxLineLen < i-lastLineIdx {
+					maxLineLen = i - lastLineIdx
+				}
+				lastLineIdx = i + 1
+				numLines++
+			}
+		}
+		isPureText := numValidRunes == numTotalRunes
+		isMostlyText = float64(numValidRunes) > math.Floor(0.90*float64(numTotalRunes))
+		isPureLinedText = isPureText && numLines >= 4 && maxLineLen <= 1024
+		isBinary = !isMostlyText
+
+		// Avoid diffing by lines if it produces a significantly more complex
+		// edit script than diffing by bytes.
+		if isPureLinedText {
+			ssx = strings.Split(sx, "\n")
+			ssy = strings.Split(sy, "\n")
+			esLines := diff.Difference(len(ssx), len(ssy), func(ix, iy int) diff.Result {
+				return diff.BoolResult(ssx[ix] == ssy[iy])
+			})
+			esBytes := diff.Difference(len(sx), len(sy), func(ix, iy int) diff.Result {
+				return diff.BoolResult(sx[ix] == sy[iy])
+			})
+			efficiencyLines := float64(esLines.Dist()) / float64(len(esLines))
+			efficiencyBytes := float64(esBytes.Dist()) / float64(len(esBytes))
+			quotedLength := len(strconv.Quote(sx + sy))
+			unquotedLength := len(sx) + len(sy)
+			escapeExpansionRatio := float64(quotedLength) / float64(unquotedLength)
+			isPureLinedText = efficiencyLines < 4*efficiencyBytes || escapeExpansionRatio > 1.1
+		}
+	}
+
+	// Format the string into printable records.
+	var list textList
+	var delim string
+	switch {
+	// If the text appears to be multi-lined text,
+	// then perform differencing across individual lines.
+	case isPureLinedText:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(ssx), reflect.ValueOf(ssy), 1, "line",
+			func(v reflect.Value, d diffMode) textRecord {
+				s := formatString(v.Index(0).String())
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+		delim = "\n"
+
+		// If possible, use a custom triple-quote (""") syntax for printing
+		// differences in a string literal. This format is more readable,
+		// but has edge-cases where differences are visually indistinguishable.
+		// This format is avoided under the following conditions:
+		//   - A line starts with `"""`
+		//   - A line starts with "..."
+		//   - A line contains non-printable characters
+		//   - Adjacent different lines differ only by whitespace
+		//
+		// For example:
+		//
+		//		"""
+		//		... // 3 identical lines
+		//		foo
+		//		bar
+		//	-	baz
+		//	+	BAZ
+		//		"""
+		isTripleQuoted := true
+		prevRemoveLines := map[string]bool{}
+		prevInsertLines := map[string]bool{}
+		var list2 textList
+		list2 = append(list2, textRecord{Value: textLine(`"""`), ElideComma: true})
+		for _, r := range list {
+			if !r.Value.Equal(textEllipsis) {
+				line, _ := strconv.Unquote(string(r.Value.(textLine)))
+				line = strings.TrimPrefix(strings.TrimSuffix(line, "\r"), "\r") // trim leading/trailing carriage returns for legacy Windows endline support
+				normLine := strings.Map(func(r rune) rune {
+					if unicode.IsSpace(r) {
+						return -1 // drop whitespace to avoid visually indistinguishable output
+					}
+					return r
+				}, line)
+				isPrintable := func(r rune) bool {
+					return unicode.IsPrint(r) || r == '\t' // specially treat tab as printable
+				}
+				isTripleQuoted = !strings.HasPrefix(line, `"""`) && !strings.HasPrefix(line, "...") && strings.TrimFunc(line, isPrintable) == ""
+				switch r.Diff {
+				case diffRemoved:
+					isTripleQuoted = isTripleQuoted && !prevInsertLines[normLine]
+					prevRemoveLines[normLine] = true
+				case diffInserted:
+					isTripleQuoted = isTripleQuoted && !prevRemoveLines[normLine]
+					prevInsertLines[normLine] = true
+				}
+				if !isTripleQuoted {
+					break
+				}
+				r.Value = textLine(line)
+				r.ElideComma = true
+			}
+			if !(r.Diff == diffRemoved || r.Diff == diffInserted) { // start a new non-adjacent difference group
+				prevRemoveLines = map[string]bool{}
+				prevInsertLines = map[string]bool{}
+			}
+			list2 = append(list2, r)
+		}
+		if r := list2[len(list2)-1]; r.Diff == diffIdentical && len(r.Value.(textLine)) == 0 {
+			list2 = list2[:len(list2)-1] // elide single empty line at the end
+		}
+		list2 = append(list2, textRecord{Value: textLine(`"""`), ElideComma: true})
+		if isTripleQuoted {
+			var out textNode = &textWrap{Prefix: "(", Value: list2, Suffix: ")"}
+			switch t.Kind() {
+			case reflect.String:
+				if t != stringType {
+					out = opts.FormatType(t, out)
+				}
+			case reflect.Slice:
+				// Always emit type for slices since the triple-quote syntax
+				// looks like a string (not a slice).
+				opts = opts.WithTypeMode(emitType)
+				out = opts.FormatType(t, out)
+			}
+			return out
+		}
+
+	// If the text appears to be single-lined text,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The output is printed as quoted strings.
+	case isMostlyText:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(sx), reflect.ValueOf(sy), 64, "byte",
+			func(v reflect.Value, d diffMode) textRecord {
+				s := formatString(v.String())
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+
+	// If the text appears to be binary data,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The output is inspired by hexdump.
+	case isBinary:
+		list = opts.formatDiffSlice(
+			reflect.ValueOf(sx), reflect.ValueOf(sy), 16, "byte",
+			func(v reflect.Value, d diffMode) textRecord {
+				var ss []string
+				for i := 0; i < v.Len(); i++ {
+					ss = append(ss, formatHex(v.Index(i).Uint()))
+				}
+				s := strings.Join(ss, ", ")
+				comment := commentString(fmt.Sprintf("%c|%v|", d, formatASCII(v.String())))
+				return textRecord{Diff: d, Value: textLine(s), Comment: comment}
+			},
+		)
+
+	// For all other slices of primitive types,
+	// then perform differencing in approximately fixed-sized chunks.
+	// The size of each chunk depends on the width of the element kind.
+	default:
+		var chunkSize int
+		if t.Elem().Kind() == reflect.Bool {
+			chunkSize = 16
+		} else {
+			switch t.Elem().Bits() {
+			case 8:
+				chunkSize = 16
+			case 16:
+				chunkSize = 12
+			case 32:
+				chunkSize = 8
+			default:
+				chunkSize = 8
+			}
+		}
+		list = opts.formatDiffSlice(
+			vx, vy, chunkSize, t.Elem().Kind().String(),
+			func(v reflect.Value, d diffMode) textRecord {
+				var ss []string
+				for i := 0; i < v.Len(); i++ {
+					switch t.Elem().Kind() {
+					case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+						ss = append(ss, fmt.Sprint(v.Index(i).Int()))
+					case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+						ss = append(ss, fmt.Sprint(v.Index(i).Uint()))
+					case reflect.Uint8, reflect.Uintptr:
+						ss = append(ss, formatHex(v.Index(i).Uint()))
+					case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128:
+						ss = append(ss, fmt.Sprint(v.Index(i).Interface()))
+					}
+				}
+				s := strings.Join(ss, ", ")
+				return textRecord{Diff: d, Value: textLine(s)}
+			},
+		)
+	}
+
+	// Wrap the output with appropriate type information.
+	var out textNode = &textWrap{Prefix: "{", Value: list, Suffix: "}"}
+	if !isMostlyText {
+		// The "{...}" byte-sequence literal is not valid Go syntax for strings.
+		// Emit the type for extra clarity (e.g. "string{...}").
+		if t.Kind() == reflect.String {
+			opts = opts.WithTypeMode(emitType)
+		}
+		return opts.FormatType(t, out)
+	}
+	switch t.Kind() {
+	case reflect.String:
+		out = &textWrap{Prefix: "strings.Join(", Value: out, Suffix: fmt.Sprintf(", %q)", delim)}
+		if t != stringType {
+			out = opts.FormatType(t, out)
+		}
+	case reflect.Slice:
+		out = &textWrap{Prefix: "bytes.Join(", Value: out, Suffix: fmt.Sprintf(", %q)", delim)}
+		if t != bytesType {
+			out = opts.FormatType(t, out)
+		}
+	}
+	return out
+}
+
+// formatASCII formats s as an ASCII string.
+// This is useful for printing binary strings in a semi-legible way.
+func formatASCII(s string) string {
+	b := bytes.Repeat([]byte{'.'}, len(s))
+	for i := 0; i < len(s); i++ {
+		if ' ' <= s[i] && s[i] <= '~' {
+			b[i] = s[i]
+		}
+	}
+	return string(b)
+}
+
+func (opts formatOptions) formatDiffSlice(
+	vx, vy reflect.Value, chunkSize int, name string,
+	makeRec func(reflect.Value, diffMode) textRecord,
+) (list textList) {
+	eq := func(ix, iy int) bool {
+		return vx.Index(ix).Interface() == vy.Index(iy).Interface()
+	}
+	es := diff.Difference(vx.Len(), vy.Len(), func(ix, iy int) diff.Result {
+		return diff.BoolResult(eq(ix, iy))
+	})
+
+	appendChunks := func(v reflect.Value, d diffMode) int {
+		n0 := v.Len()
+		for v.Len() > 0 {
+			n := chunkSize
+			if n > v.Len() {
+				n = v.Len()
+			}
+			list = append(list, makeRec(v.Slice(0, n), d))
+			v = v.Slice(n, v.Len())
+		}
+		return n0 - v.Len()
+	}
+
+	var numDiffs int
+	maxLen := -1
+	if opts.LimitVerbosity {
+		maxLen = (1 << opts.verbosity()) << 2 // 4, 8, 16, 32, 64, etc...
+		opts.VerbosityLevel--
+	}
+
+	groups := coalesceAdjacentEdits(name, es)
+	groups = coalesceInterveningIdentical(groups, chunkSize/4)
+	groups = cleanupSurroundingIdentical(groups, eq)
+	maxGroup := diffStats{Name: name}
+	for i, ds := range groups {
+		if maxLen >= 0 && numDiffs >= maxLen {
+			maxGroup = maxGroup.Append(ds)
+			continue
+		}
+
+		// Print equal.
+		if ds.NumDiff() == 0 {
+			// Compute the number of leading and trailing equal bytes to print.
+			var numLo, numHi int
+			numEqual := ds.NumIgnored + ds.NumIdentical
+			for numLo < chunkSize*numContextRecords && numLo+numHi < numEqual && i != 0 {
+				numLo++
+			}
+			for numHi < chunkSize*numContextRecords && numLo+numHi < numEqual && i != len(groups)-1 {
+				numHi++
+			}
+			if numEqual-(numLo+numHi) <= chunkSize && ds.NumIgnored == 0 {
+				numHi = numEqual - numLo // Avoid pointless coalescing of single equal row
+			}
+
+			// Print the equal bytes.
+			appendChunks(vx.Slice(0, numLo), diffIdentical)
+			if numEqual > numLo+numHi {
+				ds.NumIdentical -= numLo + numHi
+				list.AppendEllipsis(ds)
+			}
+			appendChunks(vx.Slice(numEqual-numHi, numEqual), diffIdentical)
+			vx = vx.Slice(numEqual, vx.Len())
+			vy = vy.Slice(numEqual, vy.Len())
+			continue
+		}
+
+		// Print unequal.
+		len0 := len(list)
+		nx := appendChunks(vx.Slice(0, ds.NumIdentical+ds.NumRemoved+ds.NumModified), diffRemoved)
+		vx = vx.Slice(nx, vx.Len())
+		ny := appendChunks(vy.Slice(0, ds.NumIdentical+ds.NumInserted+ds.NumModified), diffInserted)
+		vy = vy.Slice(ny, vy.Len())
+		numDiffs += len(list) - len0
+	}
+	if maxGroup.IsZero() {
+		assert(vx.Len() == 0 && vy.Len() == 0)
+	} else {
+		list.AppendEllipsis(maxGroup)
+	}
+	return list
+}
+
+// coalesceAdjacentEdits coalesces the list of edits into groups of adjacent
+// equal or unequal counts.
+//
+// Example:
+//
+//	Input:  "..XXY...Y"
+//	Output: [
+//		{NumIdentical: 2},
+//		{NumRemoved: 2, NumInserted 1},
+//		{NumIdentical: 3},
+//		{NumInserted: 1},
+//	]
+func coalesceAdjacentEdits(name string, es diff.EditScript) (groups []diffStats) {
+	var prevMode byte
+	lastStats := func(mode byte) *diffStats {
+		if prevMode != mode {
+			groups = append(groups, diffStats{Name: name})
+			prevMode = mode
+		}
+		return &groups[len(groups)-1]
+	}
+	for _, e := range es {
+		switch e {
+		case diff.Identity:
+			lastStats('=').NumIdentical++
+		case diff.UniqueX:
+			lastStats('!').NumRemoved++
+		case diff.UniqueY:
+			lastStats('!').NumInserted++
+		case diff.Modified:
+			lastStats('!').NumModified++
+		}
+	}
+	return groups
+}
+
+// coalesceInterveningIdentical coalesces sufficiently short (<= windowSize)
+// equal groups into adjacent unequal groups that currently result in a
+// dual inserted/removed printout. This acts as a high-pass filter to smooth
+// out high-frequency changes within the windowSize.
+//
+// Example:
+//
+//	WindowSize: 16,
+//	Input: [
+//		{NumIdentical: 61},              // group 0
+//		{NumRemoved: 3, NumInserted: 1}, // group 1
+//		{NumIdentical: 6},               // ├── coalesce
+//		{NumInserted: 2},                // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 9},                 // └── coalesce
+//		{NumIdentical: 64},              // group 2
+//		{NumRemoved: 3, NumInserted: 1}, // group 3
+//		{NumIdentical: 6},               // ├── coalesce
+//		{NumInserted: 2},                // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 7},                 // ├── coalesce
+//		{NumIdentical: 1},               // ├── coalesce
+//		{NumRemoved: 2},                 // └── coalesce
+//		{NumIdentical: 63},              // group 4
+//	]
+//	Output: [
+//		{NumIdentical: 61},
+//		{NumIdentical: 7, NumRemoved: 12, NumInserted: 3},
+//		{NumIdentical: 64},
+//		{NumIdentical: 8, NumRemoved: 12, NumInserted: 3},
+//		{NumIdentical: 63},
+//	]
+func coalesceInterveningIdentical(groups []diffStats, windowSize int) []diffStats {
+	groups, groupsOrig := groups[:0], groups
+	for i, ds := range groupsOrig {
+		if len(groups) >= 2 && ds.NumDiff() > 0 {
+			prev := &groups[len(groups)-2] // Unequal group
+			curr := &groups[len(groups)-1] // Equal group
+			next := &groupsOrig[i]         // Unequal group
+			hadX, hadY := prev.NumRemoved > 0, prev.NumInserted > 0
+			hasX, hasY := next.NumRemoved > 0, next.NumInserted > 0
+			if ((hadX || hasX) && (hadY || hasY)) && curr.NumIdentical <= windowSize {
+				*prev = prev.Append(*curr).Append(*next)
+				groups = groups[:len(groups)-1] // Truncate off equal group
+				continue
+			}
+		}
+		groups = append(groups, ds)
+	}
+	return groups
+}
+
+// cleanupSurroundingIdentical scans through all unequal groups, and
+// moves any leading sequence of equal elements to the preceding equal group and
+// moves and trailing sequence of equal elements to the succeeding equal group.
+//
+// This is necessary since coalesceInterveningIdentical may coalesce edit groups
+// together such that leading/trailing spans of equal elements becomes possible.
+// Note that this can occur even with an optimal diffing algorithm.
+//
+// Example:
+//
+//	Input: [
+//		{NumIdentical: 61},
+//		{NumIdentical: 1 , NumRemoved: 11, NumInserted: 2}, // assume 3 leading identical elements
+//		{NumIdentical: 67},
+//		{NumIdentical: 7, NumRemoved: 12, NumInserted: 3},  // assume 10 trailing identical elements
+//		{NumIdentical: 54},
+//	]
+//	Output: [
+//		{NumIdentical: 64}, // incremented by 3
+//		{NumRemoved: 9},
+//		{NumIdentical: 67},
+//		{NumRemoved: 9},
+//		{NumIdentical: 64}, // incremented by 10
+//	]
+func cleanupSurroundingIdentical(groups []diffStats, eq func(i, j int) bool) []diffStats {
+	var ix, iy int // indexes into sequence x and y
+	for i, ds := range groups {
+		// Handle equal group.
+		if ds.NumDiff() == 0 {
+			ix += ds.NumIdentical
+			iy += ds.NumIdentical
+			continue
+		}
+
+		// Handle unequal group.
+		nx := ds.NumIdentical + ds.NumRemoved + ds.NumModified
+		ny := ds.NumIdentical + ds.NumInserted + ds.NumModified
+		var numLeadingIdentical, numTrailingIdentical int
+		for j := 0; j < nx && j < ny && eq(ix+j, iy+j); j++ {
+			numLeadingIdentical++
+		}
+		for j := 0; j < nx && j < ny && eq(ix+nx-1-j, iy+ny-1-j); j++ {
+			numTrailingIdentical++
+		}
+		if numIdentical := numLeadingIdentical + numTrailingIdentical; numIdentical > 0 {
+			if numLeadingIdentical > 0 {
+				// Remove leading identical span from this group and
+				// insert it into the preceding group.
+				if i-1 >= 0 {
+					groups[i-1].NumIdentical += numLeadingIdentical
+				} else {
+					// No preceding group exists, so prepend a new group,
+					// but do so after we finish iterating over all groups.
+					defer func() {
+						groups = append([]diffStats{{Name: groups[0].Name, NumIdentical: numLeadingIdentical}}, groups...)
+					}()
+				}
+				// Increment indexes since the preceding group would have handled this.
+				ix += numLeadingIdentical
+				iy += numLeadingIdentical
+			}
+			if numTrailingIdentical > 0 {
+				// Remove trailing identical span from this group and
+				// insert it into the succeeding group.
+				if i+1 < len(groups) {
+					groups[i+1].NumIdentical += numTrailingIdentical
+				} else {
+					// No succeeding group exists, so append a new group,
+					// but do so after we finish iterating over all groups.
+					defer func() {
+						groups = append(groups, diffStats{Name: groups[len(groups)-1].Name, NumIdentical: numTrailingIdentical})
+					}()
+				}
+				// Do not increment indexes since the succeeding group will handle this.
+			}
+
+			// Update this group since some identical elements were removed.
+			nx -= numIdentical
+			ny -= numIdentical
+			groups[i] = diffStats{Name: ds.Name, NumRemoved: nx, NumInserted: ny}
+		}
+		ix += nx
+		iy += ny
+	}
+	return groups
+}

vendor/github.com/google/go-cmp/cmp/report_text.go

@@ -0,0 +1,432 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import (
+	"bytes"
+	"fmt"
+	"math/rand"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"github.com/google/go-cmp/cmp/internal/flags"
+)
+
+var randBool = rand.New(rand.NewSource(time.Now().Unix())).Intn(2) == 0
+
+const maxColumnLength = 80
+
+type indentMode int
+
+func (n indentMode) appendIndent(b []byte, d diffMode) []byte {
+	// The output of Diff is documented as being unstable to provide future
+	// flexibility in changing the output for more humanly readable reports.
+	// This logic intentionally introduces instability to the exact output
+	// so that users can detect accidental reliance on stability early on,
+	// rather than much later when an actual change to the format occurs.
+	if flags.Deterministic || randBool {
+		// Use regular spaces (U+0020).
+		switch d {
+		case diffUnknown, diffIdentical:
+			b = append(b, "  "...)
+		case diffRemoved:
+			b = append(b, "- "...)
+		case diffInserted:
+			b = append(b, "+ "...)
+		}
+	} else {
+		// Use non-breaking spaces (U+00a0).
+		switch d {
+		case diffUnknown, diffIdentical:
+			b = append(b, "  "...)
+		case diffRemoved:
+			b = append(b, "- "...)
+		case diffInserted:
+			b = append(b, "+ "...)
+		}
+	}
+	return repeatCount(n).appendChar(b, '\t')
+}
+
+type repeatCount int
+
+func (n repeatCount) appendChar(b []byte, c byte) []byte {
+	for ; n > 0; n-- {
+		b = append(b, c)
+	}
+	return b
+}
+
+// textNode is a simplified tree-based representation of structured text.
+// Possible node types are textWrap, textList, or textLine.
+type textNode interface {
+	// Len reports the length in bytes of a single-line version of the tree.
+	// Nested textRecord.Diff and textRecord.Comment fields are ignored.
+	Len() int
+	// Equal reports whether the two trees are structurally identical.
+	// Nested textRecord.Diff and textRecord.Comment fields are compared.
+	Equal(textNode) bool
+	// String returns the string representation of the text tree.
+	// It is not guaranteed that len(x.String()) == x.Len(),
+	// nor that x.String() == y.String() implies that x.Equal(y).
+	String() string
+
+	// formatCompactTo formats the contents of the tree as a single-line string
+	// to the provided buffer. Any nested textRecord.Diff and textRecord.Comment
+	// fields are ignored.
+	//
+	// However, not all nodes in the tree should be collapsed as a single-line.
+	// If a node can be collapsed as a single-line, it is replaced by a textLine
+	// node. Since the top-level node cannot replace itself, this also returns
+	// the current node itself.
+	//
+	// This does not mutate the receiver.
+	formatCompactTo([]byte, diffMode) ([]byte, textNode)
+	// formatExpandedTo formats the contents of the tree as a multi-line string
+	// to the provided buffer. In order for column alignment to operate well,
+	// formatCompactTo must be called before calling formatExpandedTo.
+	formatExpandedTo([]byte, diffMode, indentMode) []byte
+}
+
+// textWrap is a wrapper that concatenates a prefix and/or a suffix
+// to the underlying node.
+type textWrap struct {
+	Prefix   string      // e.g., "bytes.Buffer{"
+	Value    textNode    // textWrap | textList | textLine
+	Suffix   string      // e.g., "}"
+	Metadata interface{} // arbitrary metadata; has no effect on formatting
+}
+
+func (s *textWrap) Len() int {
+	return len(s.Prefix) + s.Value.Len() + len(s.Suffix)
+}
+func (s1 *textWrap) Equal(s2 textNode) bool {
+	if s2, ok := s2.(*textWrap); ok {
+		return s1.Prefix == s2.Prefix && s1.Value.Equal(s2.Value) && s1.Suffix == s2.Suffix
+	}
+	return false
+}
+func (s *textWrap) String() string {
+	var d diffMode
+	var n indentMode
+	_, s2 := s.formatCompactTo(nil, d)
+	b := n.appendIndent(nil, d)      // Leading indent
+	b = s2.formatExpandedTo(b, d, n) // Main body
+	b = append(b, '\n')              // Trailing newline
+	return string(b)
+}
+func (s *textWrap) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	n0 := len(b) // Original buffer length
+	b = append(b, s.Prefix...)
+	b, s.Value = s.Value.formatCompactTo(b, d)
+	b = append(b, s.Suffix...)
+	if _, ok := s.Value.(textLine); ok {
+		return b, textLine(b[n0:])
+	}
+	return b, s
+}
+func (s *textWrap) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte {
+	b = append(b, s.Prefix...)
+	b = s.Value.formatExpandedTo(b, d, n)
+	b = append(b, s.Suffix...)
+	return b
+}
+
+// textList is a comma-separated list of textWrap or textLine nodes.
+// The list may be formatted as multi-lines or single-line at the discretion
+// of the textList.formatCompactTo method.
+type textList []textRecord
+type textRecord struct {
+	Diff       diffMode     // e.g., 0 or '-' or '+'
+	Key        string       // e.g., "MyField"
+	Value      textNode     // textWrap | textLine
+	ElideComma bool         // avoid trailing comma
+	Comment    fmt.Stringer // e.g., "6 identical fields"
+}
+
+// AppendEllipsis appends a new ellipsis node to the list if none already
+// exists at the end. If cs is non-zero it coalesces the statistics with the
+// previous diffStats.
+func (s *textList) AppendEllipsis(ds diffStats) {
+	hasStats := !ds.IsZero()
+	if len(*s) == 0 || !(*s)[len(*s)-1].Value.Equal(textEllipsis) {
+		if hasStats {
+			*s = append(*s, textRecord{Value: textEllipsis, ElideComma: true, Comment: ds})
+		} else {
+			*s = append(*s, textRecord{Value: textEllipsis, ElideComma: true})
+		}
+		return
+	}
+	if hasStats {
+		(*s)[len(*s)-1].Comment = (*s)[len(*s)-1].Comment.(diffStats).Append(ds)
+	}
+}
+
+func (s textList) Len() (n int) {
+	for i, r := range s {
+		n += len(r.Key)
+		if r.Key != "" {
+			n += len(": ")
+		}
+		n += r.Value.Len()
+		if i < len(s)-1 {
+			n += len(", ")
+		}
+	}
+	return n
+}
+
+func (s1 textList) Equal(s2 textNode) bool {
+	if s2, ok := s2.(textList); ok {
+		if len(s1) != len(s2) {
+			return false
+		}
+		for i := range s1 {
+			r1, r2 := s1[i], s2[i]
+			if !(r1.Diff == r2.Diff && r1.Key == r2.Key && r1.Value.Equal(r2.Value) && r1.Comment == r2.Comment) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
+func (s textList) String() string {
+	return (&textWrap{Prefix: "{", Value: s, Suffix: "}"}).String()
+}
+
+func (s textList) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	s = append(textList(nil), s...) // Avoid mutating original
+
+	// Determine whether we can collapse this list as a single line.
+	n0 := len(b) // Original buffer length
+	var multiLine bool
+	for i, r := range s {
+		if r.Diff == diffInserted || r.Diff == diffRemoved {
+			multiLine = true
+		}
+		b = append(b, r.Key...)
+		if r.Key != "" {
+			b = append(b, ": "...)
+		}
+		b, s[i].Value = r.Value.formatCompactTo(b, d|r.Diff)
+		if _, ok := s[i].Value.(textLine); !ok {
+			multiLine = true
+		}
+		if r.Comment != nil {
+			multiLine = true
+		}
+		if i < len(s)-1 {
+			b = append(b, ", "...)
+		}
+	}
+	// Force multi-lined output when printing a removed/inserted node that
+	// is sufficiently long.
+	if (d == diffInserted || d == diffRemoved) && len(b[n0:]) > maxColumnLength {
+		multiLine = true
+	}
+	if !multiLine {
+		return b, textLine(b[n0:])
+	}
+	return b, s
+}
+
+func (s textList) formatExpandedTo(b []byte, d diffMode, n indentMode) []byte {
+	alignKeyLens := s.alignLens(
+		func(r textRecord) bool {
+			_, isLine := r.Value.(textLine)
+			return r.Key == "" || !isLine
+		},
+		func(r textRecord) int { return utf8.RuneCountInString(r.Key) },
+	)
+	alignValueLens := s.alignLens(
+		func(r textRecord) bool {
+			_, isLine := r.Value.(textLine)
+			return !isLine || r.Value.Equal(textEllipsis) || r.Comment == nil
+		},
+		func(r textRecord) int { return utf8.RuneCount(r.Value.(textLine)) },
+	)
+
+	// Format lists of simple lists in a batched form.
+	// If the list is sequence of only textLine values,
+	// then batch multiple values on a single line.
+	var isSimple bool
+	for _, r := range s {
+		_, isLine := r.Value.(textLine)
+		isSimple = r.Diff == 0 && r.Key == "" && isLine && r.Comment == nil
+		if !isSimple {
+			break
+		}
+	}
+	if isSimple {
+		n++
+		var batch []byte
+		emitBatch := func() {
+			if len(batch) > 0 {
+				b = n.appendIndent(append(b, '\n'), d)
+				b = append(b, bytes.TrimRight(batch, " ")...)
+				batch = batch[:0]
+			}
+		}
+		for _, r := range s {
+			line := r.Value.(textLine)
+			if len(batch)+len(line)+len(", ") > maxColumnLength {
+				emitBatch()
+			}
+			batch = append(batch, line...)
+			batch = append(batch, ", "...)
+		}
+		emitBatch()
+		n--
+		return n.appendIndent(append(b, '\n'), d)
+	}
+
+	// Format the list as a multi-lined output.
+	n++
+	for i, r := range s {
+		b = n.appendIndent(append(b, '\n'), d|r.Diff)
+		if r.Key != "" {
+			b = append(b, r.Key+": "...)
+		}
+		b = alignKeyLens[i].appendChar(b, ' ')
+
+		b = r.Value.formatExpandedTo(b, d|r.Diff, n)
+		if !r.ElideComma {
+			b = append(b, ',')
+		}
+		b = alignValueLens[i].appendChar(b, ' ')
+
+		if r.Comment != nil {
+			b = append(b, " // "+r.Comment.String()...)
+		}
+	}
+	n--
+
+	return n.appendIndent(append(b, '\n'), d)
+}
+
+func (s textList) alignLens(
+	skipFunc func(textRecord) bool,
+	lenFunc func(textRecord) int,
+) []repeatCount {
+	var startIdx, endIdx, maxLen int
+	lens := make([]repeatCount, len(s))
+	for i, r := range s {
+		if skipFunc(r) {
+			for j := startIdx; j < endIdx && j < len(s); j++ {
+				lens[j] = repeatCount(maxLen - lenFunc(s[j]))
+			}
+			startIdx, endIdx, maxLen = i+1, i+1, 0
+		} else {
+			if maxLen < lenFunc(r) {
+				maxLen = lenFunc(r)
+			}
+			endIdx = i + 1
+		}
+	}
+	for j := startIdx; j < endIdx && j < len(s); j++ {
+		lens[j] = repeatCount(maxLen - lenFunc(s[j]))
+	}
+	return lens
+}
+
+// textLine is a single-line segment of text and is always a leaf node
+// in the textNode tree.
+type textLine []byte
+
+var (
+	textNil      = textLine("nil")
+	textEllipsis = textLine("...")
+)
+
+func (s textLine) Len() int {
+	return len(s)
+}
+func (s1 textLine) Equal(s2 textNode) bool {
+	if s2, ok := s2.(textLine); ok {
+		return bytes.Equal([]byte(s1), []byte(s2))
+	}
+	return false
+}
+func (s textLine) String() string {
+	return string(s)
+}
+func (s textLine) formatCompactTo(b []byte, d diffMode) ([]byte, textNode) {
+	return append(b, s...), s
+}
+func (s textLine) formatExpandedTo(b []byte, _ diffMode, _ indentMode) []byte {
+	return append(b, s...)
+}
+
+type diffStats struct {
+	Name         string
+	NumIgnored   int
+	NumIdentical int
+	NumRemoved   int
+	NumInserted  int
+	NumModified  int
+}
+
+func (s diffStats) IsZero() bool {
+	s.Name = ""
+	return s == diffStats{}
+}
+
+func (s diffStats) NumDiff() int {
+	return s.NumRemoved + s.NumInserted + s.NumModified
+}
+
+func (s diffStats) Append(ds diffStats) diffStats {
+	assert(s.Name == ds.Name)
+	s.NumIgnored += ds.NumIgnored
+	s.NumIdentical += ds.NumIdentical
+	s.NumRemoved += ds.NumRemoved
+	s.NumInserted += ds.NumInserted
+	s.NumModified += ds.NumModified
+	return s
+}
+
+// String prints a humanly-readable summary of coalesced records.
+//
+// Example:
+//
+//	diffStats{Name: "Field", NumIgnored: 5}.String() => "5 ignored fields"
+func (s diffStats) String() string {
+	var ss []string
+	var sum int
+	labels := [...]string{"ignored", "identical", "removed", "inserted", "modified"}
+	counts := [...]int{s.NumIgnored, s.NumIdentical, s.NumRemoved, s.NumInserted, s.NumModified}
+	for i, n := range counts {
+		if n > 0 {
+			ss = append(ss, fmt.Sprintf("%d %v", n, labels[i]))
+		}
+		sum += n
+	}
+
+	// Pluralize the name (adjusting for some obscure English grammar rules).
+	name := s.Name
+	if sum > 1 {
+		name += "s"
+		if strings.HasSuffix(name, "ys") {
+			name = name[:len(name)-2] + "ies" // e.g., "entrys" => "entries"
+		}
+	}
+
+	// Format the list according to English grammar (with Oxford comma).
+	switch n := len(ss); n {
+	case 0:
+		return ""
+	case 1, 2:
+		return strings.Join(ss, " and ") + " " + name
+	default:
+		return strings.Join(ss[:n-1], ", ") + ", and " + ss[n-1] + " " + name
+	}
+}
+
+type commentString string
+
+func (s commentString) String() string { return string(s) }

vendor/github.com/google/go-cmp/cmp/report_value.go

@@ -0,0 +1,121 @@
+// Copyright 2019, The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cmp
+
+import "reflect"
+
+// valueNode represents a single node within a report, which is a
+// structured representation of the value tree, containing information
+// regarding which nodes are equal or not.
+type valueNode struct {
+	parent *valueNode
+
+	Type   reflect.Type
+	ValueX reflect.Value
+	ValueY reflect.Value
+
+	// NumSame is the number of leaf nodes that are equal.
+	// All descendants are equal only if NumDiff is 0.
+	NumSame int
+	// NumDiff is the number of leaf nodes that are not equal.
+	NumDiff int
+	// NumIgnored is the number of leaf nodes that are ignored.
+	NumIgnored int
+	// NumCompared is the number of leaf nodes that were compared
+	// using an Equal method or Comparer function.
+	NumCompared int
+	// NumTransformed is the number of non-leaf nodes that were transformed.
+	NumTransformed int
+	// NumChildren is the number of transitive descendants of this node.
+	// This counts from zero; thus, leaf nodes have no descendants.
+	NumChildren int
+	// MaxDepth is the maximum depth of the tree. This counts from zero;
+	// thus, leaf nodes have a depth of zero.
+	MaxDepth int
+
+	// Records is a list of struct fields, slice elements, or map entries.
+	Records []reportRecord // If populated, implies Value is not populated
+
+	// Value is the result of a transformation, pointer indirect, of
+	// type assertion.
+	Value *valueNode // If populated, implies Records is not populated
+
+	// TransformerName is the name of the transformer.
+	TransformerName string // If non-empty, implies Value is populated
+}
+type reportRecord struct {
+	Key   reflect.Value // Invalid for slice element
+	Value *valueNode
+}
+
+func (parent *valueNode) PushStep(ps PathStep) (child *valueNode) {
+	vx, vy := ps.Values()
+	child = &valueNode{parent: parent, Type: ps.Type(), ValueX: vx, ValueY: vy}
+	switch s := ps.(type) {
+	case StructField:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Key: reflect.ValueOf(s.Name()), Value: child})
+	case SliceIndex:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Value: child})
+	case MapIndex:
+		assert(parent.Value == nil)
+		parent.Records = append(parent.Records, reportRecord{Key: s.Key(), Value: child})
+	case Indirect:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+	case TypeAssertion:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+	case Transform:
+		assert(parent.Value == nil && parent.Records == nil)
+		parent.Value = child
+		parent.TransformerName = s.Name()
+		parent.NumTransformed++
+	default:
+		assert(parent == nil) // Must be the root step
+	}
+	return child
+}
+
+func (r *valueNode) Report(rs Result) {
+	assert(r.MaxDepth == 0) // May only be called on leaf nodes
+
+	if rs.ByIgnore() {
+		r.NumIgnored++
+	} else {
+		if rs.Equal() {
+			r.NumSame++
+		} else {
+			r.NumDiff++
+		}
+	}
+	assert(r.NumSame+r.NumDiff+r.NumIgnored == 1)
+
+	if rs.ByMethod() {
+		r.NumCompared++
+	}
+	if rs.ByFunc() {
+		r.NumCompared++
+	}
+	assert(r.NumCompared <= 1)
+}
+
+func (child *valueNode) PopStep() (parent *valueNode) {
+	if child.parent == nil {
+		return nil
+	}
+	parent = child.parent
+	parent.NumSame += child.NumSame
+	parent.NumDiff += child.NumDiff
+	parent.NumIgnored += child.NumIgnored
+	parent.NumCompared += child.NumCompared
+	parent.NumTransformed += child.NumTransformed
+	parent.NumChildren += child.NumChildren + 1
+	if parent.MaxDepth < child.MaxDepth+1 {
+		parent.MaxDepth = child.MaxDepth + 1
+	}
+	return parent
+}

vendor/gopkg.in/yaml.v2/.travis.yml

@@ -0,0 +1,16 @@
+language: go
+
+go:
+    - "1.4.x"
+    - "1.5.x"
+    - "1.6.x"
+    - "1.7.x"
+    - "1.8.x"
+    - "1.9.x"
+    - "1.10.x"
+    - "1.11.x"
+    - "1.12.x"
+    - "1.13.x"
+    - "tip"
+
+go_import_path: gopkg.in/yaml.v2

vendor/gopkg.in/yaml.v2/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "{}"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright {yyyy} {name of copyright owner}
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/gopkg.in/yaml.v2/LICENSE.libyaml

@@ -0,0 +1,31 @@
+The following files were ported to Go from C files of libyaml, and thus
+are still covered by their original copyright and license:
+
+    apic.go
+    emitterc.go
+    parserc.go
+    readerc.go
+    scannerc.go
+    writerc.go
+    yamlh.go
+    yamlprivateh.go
+
+Copyright (c) 2006 Kirill Simonov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/gopkg.in/yaml.v2/NOTICE

@@ -0,0 +1,13 @@
+Copyright 2011-2016 Canonical Ltd.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/gopkg.in/yaml.v2/README.md

@@ -0,0 +1,133 @@
+# YAML support for the Go language
+
+Introduction
+------------
+
+The yaml package enables Go programs to comfortably encode and decode YAML
+values. It was developed within [Canonical](https://www.canonical.com) as
+part of the [juju](https://juju.ubuntu.com) project, and is based on a
+pure Go port of the well-known [libyaml](http://pyyaml.org/wiki/LibYAML)
+C library to parse and generate YAML data quickly and reliably.
+
+Compatibility
+-------------
+
+The yaml package supports most of YAML 1.1 and 1.2, including support for
+anchors, tags, map merging, etc. Multi-document unmarshalling is not yet
+implemented, and base-60 floats from YAML 1.1 are purposefully not
+supported since they're a poor design and are gone in YAML 1.2.
+
+Installation and usage
+----------------------
+
+The import path for the package is *gopkg.in/yaml.v2*.
+
+To install it, run:
+
+    go get gopkg.in/yaml.v2
+
+API documentation
+-----------------
+
+If opened in a browser, the import path itself leads to the API documentation:
+
+  * [https://gopkg.in/yaml.v2](https://gopkg.in/yaml.v2)
+
+API stability
+-------------
+
+The package API for yaml v2 will remain stable as described in [gopkg.in](https://gopkg.in).
+
+
+License
+-------
+
+The yaml package is licensed under the Apache License 2.0. Please see the LICENSE file for details.
+
+
+Example
+-------
+
+```Go
+package main
+
+import (
+        "fmt"
+        "log"
+
+        "gopkg.in/yaml.v2"
+)
+
+var data = `
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+`
+
+// Note: struct fields must be public in order for unmarshal to
+// correctly populate the data.
+type T struct {
+        A string
+        B struct {
+                RenamedC int   `yaml:"c"`
+                D        []int `yaml:",flow"`
+        }
+}
+
+func main() {
+        t := T{}
+    
+        err := yaml.Unmarshal([]byte(data), &t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t:\n%v\n\n", t)
+    
+        d, err := yaml.Marshal(&t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t dump:\n%s\n\n", string(d))
+    
+        m := make(map[interface{}]interface{})
+    
+        err = yaml.Unmarshal([]byte(data), &m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m:\n%v\n\n", m)
+    
+        d, err = yaml.Marshal(&m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m dump:\n%s\n\n", string(d))
+}
+```
+
+This example will generate the following output:
+
+```
+--- t:
+{Easy! {2 [3 4]}}
+
+--- t dump:
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+
+
+--- m:
+map[a:Easy! b:map[c:2 d:[3 4]]]
+
+--- m dump:
+a: Easy!
+b:
+  c: 2
+  d:
+  - 3
+  - 4
+```
+

vendor/gopkg.in/yaml.v2/apic.go

@@ -0,0 +1,740 @@
+package yaml
+
+import (
+	"io"
+)
+
+func yaml_insert_token(parser *yaml_parser_t, pos int, token *yaml_token_t) {
+	//fmt.Println("yaml_insert_token", "pos:", pos, "typ:", token.typ, "head:", parser.tokens_head, "len:", len(parser.tokens))
+
+	// Check if we can move the queue at the beginning of the buffer.
+	if parser.tokens_head > 0 && len(parser.tokens) == cap(parser.tokens) {
+		if parser.tokens_head != len(parser.tokens) {
+			copy(parser.tokens, parser.tokens[parser.tokens_head:])
+		}
+		parser.tokens = parser.tokens[:len(parser.tokens)-parser.tokens_head]
+		parser.tokens_head = 0
+	}
+	parser.tokens = append(parser.tokens, *token)
+	if pos < 0 {
+		return
+	}
+	copy(parser.tokens[parser.tokens_head+pos+1:], parser.tokens[parser.tokens_head+pos:])
+	parser.tokens[parser.tokens_head+pos] = *token
+}
+
+// Create a new parser object.
+func yaml_parser_initialize(parser *yaml_parser_t) bool {
+	*parser = yaml_parser_t{
+		raw_buffer: make([]byte, 0, input_raw_buffer_size),
+		buffer:     make([]byte, 0, input_buffer_size),
+	}
+	return true
+}
+
+// Destroy a parser object.
+func yaml_parser_delete(parser *yaml_parser_t) {
+	*parser = yaml_parser_t{}
+}
+
+// String read handler.
+func yaml_string_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	if parser.input_pos == len(parser.input) {
+		return 0, io.EOF
+	}
+	n = copy(buffer, parser.input[parser.input_pos:])
+	parser.input_pos += n
+	return n, nil
+}
+
+// Reader read handler.
+func yaml_reader_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	return parser.input_reader.Read(buffer)
+}
+
+// Set a string input.
+func yaml_parser_set_input_string(parser *yaml_parser_t, input []byte) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_string_read_handler
+	parser.input = input
+	parser.input_pos = 0
+}
+
+// Set a file input.
+func yaml_parser_set_input_reader(parser *yaml_parser_t, r io.Reader) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_reader_read_handler
+	parser.input_reader = r
+}
+
+// Set the source encoding.
+func yaml_parser_set_encoding(parser *yaml_parser_t, encoding yaml_encoding_t) {
+	if parser.encoding != yaml_ANY_ENCODING {
+		panic("must set the encoding only once")
+	}
+	parser.encoding = encoding
+}
+
+// Create a new emitter object.
+func yaml_emitter_initialize(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{
+		buffer:     make([]byte, output_buffer_size),
+		raw_buffer: make([]byte, 0, output_raw_buffer_size),
+		states:     make([]yaml_emitter_state_t, 0, initial_stack_size),
+		events:     make([]yaml_event_t, 0, initial_queue_size),
+		best_width: -1,
+	}
+}
+
+// Destroy an emitter object.
+func yaml_emitter_delete(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{}
+}
+
+// String write handler.
+func yaml_string_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	*emitter.output_buffer = append(*emitter.output_buffer, buffer...)
+	return nil
+}
+
+// yaml_writer_write_handler uses emitter.output_writer to write the
+// emitted text.
+func yaml_writer_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	_, err := emitter.output_writer.Write(buffer)
+	return err
+}
+
+// Set a string output.
+func yaml_emitter_set_output_string(emitter *yaml_emitter_t, output_buffer *[]byte) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_string_write_handler
+	emitter.output_buffer = output_buffer
+}
+
+// Set a file output.
+func yaml_emitter_set_output_writer(emitter *yaml_emitter_t, w io.Writer) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_writer_write_handler
+	emitter.output_writer = w
+}
+
+// Set the output encoding.
+func yaml_emitter_set_encoding(emitter *yaml_emitter_t, encoding yaml_encoding_t) {
+	if emitter.encoding != yaml_ANY_ENCODING {
+		panic("must set the output encoding only once")
+	}
+	emitter.encoding = encoding
+}
+
+// Set the canonical output style.
+func yaml_emitter_set_canonical(emitter *yaml_emitter_t, canonical bool) {
+	emitter.canonical = canonical
+}
+
+//// Set the indentation increment.
+func yaml_emitter_set_indent(emitter *yaml_emitter_t, indent int) {
+	if indent < 2 || indent > 9 {
+		indent = 2
+	}
+	emitter.best_indent = indent
+}
+
+// Set the preferred line width.
+func yaml_emitter_set_width(emitter *yaml_emitter_t, width int) {
+	if width < 0 {
+		width = -1
+	}
+	emitter.best_width = width
+}
+
+// Set if unescaped non-ASCII characters are allowed.
+func yaml_emitter_set_unicode(emitter *yaml_emitter_t, unicode bool) {
+	emitter.unicode = unicode
+}
+
+// Set the preferred line break character.
+func yaml_emitter_set_break(emitter *yaml_emitter_t, line_break yaml_break_t) {
+	emitter.line_break = line_break
+}
+
+///*
+// * Destroy a token object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_token_delete(yaml_token_t *token)
+//{
+//    assert(token);  // Non-NULL token object expected.
+//
+//    switch (token.type)
+//    {
+//        case YAML_TAG_DIRECTIVE_TOKEN:
+//            yaml_free(token.data.tag_directive.handle);
+//            yaml_free(token.data.tag_directive.prefix);
+//            break;
+//
+//        case YAML_ALIAS_TOKEN:
+//            yaml_free(token.data.alias.value);
+//            break;
+//
+//        case YAML_ANCHOR_TOKEN:
+//            yaml_free(token.data.anchor.value);
+//            break;
+//
+//        case YAML_TAG_TOKEN:
+//            yaml_free(token.data.tag.handle);
+//            yaml_free(token.data.tag.suffix);
+//            break;
+//
+//        case YAML_SCALAR_TOKEN:
+//            yaml_free(token.data.scalar.value);
+//            break;
+//
+//        default:
+//            break;
+//    }
+//
+//    memset(token, 0, sizeof(yaml_token_t));
+//}
+//
+///*
+// * Check if a string is a valid UTF-8 sequence.
+// *
+// * Check 'reader.c' for more details on UTF-8 encoding.
+// */
+//
+//static int
+//yaml_check_utf8(yaml_char_t *start, size_t length)
+//{
+//    yaml_char_t *end = start+length;
+//    yaml_char_t *pointer = start;
+//
+//    while (pointer < end) {
+//        unsigned char octet;
+//        unsigned int width;
+//        unsigned int value;
+//        size_t k;
+//
+//        octet = pointer[0];
+//        width = (octet & 0x80) == 0x00 ? 1 :
+//                (octet & 0xE0) == 0xC0 ? 2 :
+//                (octet & 0xF0) == 0xE0 ? 3 :
+//                (octet & 0xF8) == 0xF0 ? 4 : 0;
+//        value = (octet & 0x80) == 0x00 ? octet & 0x7F :
+//                (octet & 0xE0) == 0xC0 ? octet & 0x1F :
+//                (octet & 0xF0) == 0xE0 ? octet & 0x0F :
+//                (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
+//        if (!width) return 0;
+//        if (pointer+width > end) return 0;
+//        for (k = 1; k < width; k ++) {
+//            octet = pointer[k];
+//            if ((octet & 0xC0) != 0x80) return 0;
+//            value = (value << 6) + (octet & 0x3F);
+//        }
+//        if (!((width == 1) ||
+//            (width == 2 && value >= 0x80) ||
+//            (width == 3 && value >= 0x800) ||
+//            (width == 4 && value >= 0x10000))) return 0;
+//
+//        pointer += width;
+//    }
+//
+//    return 1;
+//}
+//
+
+// Create STREAM-START.
+func yaml_stream_start_event_initialize(event *yaml_event_t, encoding yaml_encoding_t) {
+	*event = yaml_event_t{
+		typ:      yaml_STREAM_START_EVENT,
+		encoding: encoding,
+	}
+}
+
+// Create STREAM-END.
+func yaml_stream_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_STREAM_END_EVENT,
+	}
+}
+
+// Create DOCUMENT-START.
+func yaml_document_start_event_initialize(
+	event *yaml_event_t,
+	version_directive *yaml_version_directive_t,
+	tag_directives []yaml_tag_directive_t,
+	implicit bool,
+) {
+	*event = yaml_event_t{
+		typ:               yaml_DOCUMENT_START_EVENT,
+		version_directive: version_directive,
+		tag_directives:    tag_directives,
+		implicit:          implicit,
+	}
+}
+
+// Create DOCUMENT-END.
+func yaml_document_end_event_initialize(event *yaml_event_t, implicit bool) {
+	*event = yaml_event_t{
+		typ:      yaml_DOCUMENT_END_EVENT,
+		implicit: implicit,
+	}
+}
+
+///*
+// * Create ALIAS.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_alias_event_initialize(event *yaml_event_t, anchor *yaml_char_t)
+//{
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    anchor_copy *yaml_char_t = NULL
+//
+//    assert(event) // Non-NULL event object is expected.
+//    assert(anchor) // Non-NULL anchor is expected.
+//
+//    if (!yaml_check_utf8(anchor, strlen((char *)anchor))) return 0
+//
+//    anchor_copy = yaml_strdup(anchor)
+//    if (!anchor_copy)
+//        return 0
+//
+//    ALIAS_EVENT_INIT(*event, anchor_copy, mark, mark)
+//
+//    return 1
+//}
+
+// Create SCALAR.
+func yaml_scalar_event_initialize(event *yaml_event_t, anchor, tag, value []byte, plain_implicit, quoted_implicit bool, style yaml_scalar_style_t) bool {
+	*event = yaml_event_t{
+		typ:             yaml_SCALAR_EVENT,
+		anchor:          anchor,
+		tag:             tag,
+		value:           value,
+		implicit:        plain_implicit,
+		quoted_implicit: quoted_implicit,
+		style:           yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-START.
+func yaml_sequence_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_sequence_style_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_SEQUENCE_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-END.
+func yaml_sequence_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_SEQUENCE_END_EVENT,
+	}
+	return true
+}
+
+// Create MAPPING-START.
+func yaml_mapping_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_mapping_style_t) {
+	*event = yaml_event_t{
+		typ:      yaml_MAPPING_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+}
+
+// Create MAPPING-END.
+func yaml_mapping_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_MAPPING_END_EVENT,
+	}
+}
+
+// Destroy an event object.
+func yaml_event_delete(event *yaml_event_t) {
+	*event = yaml_event_t{}
+}
+
+///*
+// * Create a document object.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_initialize(document *yaml_document_t,
+//        version_directive *yaml_version_directive_t,
+//        tag_directives_start *yaml_tag_directive_t,
+//        tag_directives_end *yaml_tag_directive_t,
+//        start_implicit int, end_implicit int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    struct {
+//        start *yaml_node_t
+//        end *yaml_node_t
+//        top *yaml_node_t
+//    } nodes = { NULL, NULL, NULL }
+//    version_directive_copy *yaml_version_directive_t = NULL
+//    struct {
+//        start *yaml_tag_directive_t
+//        end *yaml_tag_directive_t
+//        top *yaml_tag_directive_t
+//    } tag_directives_copy = { NULL, NULL, NULL }
+//    value yaml_tag_directive_t = { NULL, NULL }
+//    mark yaml_mark_t = { 0, 0, 0 }
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert((tag_directives_start && tag_directives_end) ||
+//            (tag_directives_start == tag_directives_end))
+//                            // Valid tag directives are expected.
+//
+//    if (!STACK_INIT(&context, nodes, INITIAL_STACK_SIZE)) goto error
+//
+//    if (version_directive) {
+//        version_directive_copy = yaml_malloc(sizeof(yaml_version_directive_t))
+//        if (!version_directive_copy) goto error
+//        version_directive_copy.major = version_directive.major
+//        version_directive_copy.minor = version_directive.minor
+//    }
+//
+//    if (tag_directives_start != tag_directives_end) {
+//        tag_directive *yaml_tag_directive_t
+//        if (!STACK_INIT(&context, tag_directives_copy, INITIAL_STACK_SIZE))
+//            goto error
+//        for (tag_directive = tag_directives_start
+//                tag_directive != tag_directives_end; tag_directive ++) {
+//            assert(tag_directive.handle)
+//            assert(tag_directive.prefix)
+//            if (!yaml_check_utf8(tag_directive.handle,
+//                        strlen((char *)tag_directive.handle)))
+//                goto error
+//            if (!yaml_check_utf8(tag_directive.prefix,
+//                        strlen((char *)tag_directive.prefix)))
+//                goto error
+//            value.handle = yaml_strdup(tag_directive.handle)
+//            value.prefix = yaml_strdup(tag_directive.prefix)
+//            if (!value.handle || !value.prefix) goto error
+//            if (!PUSH(&context, tag_directives_copy, value))
+//                goto error
+//            value.handle = NULL
+//            value.prefix = NULL
+//        }
+//    }
+//
+//    DOCUMENT_INIT(*document, nodes.start, nodes.end, version_directive_copy,
+//            tag_directives_copy.start, tag_directives_copy.top,
+//            start_implicit, end_implicit, mark, mark)
+//
+//    return 1
+//
+//error:
+//    STACK_DEL(&context, nodes)
+//    yaml_free(version_directive_copy)
+//    while (!STACK_EMPTY(&context, tag_directives_copy)) {
+//        value yaml_tag_directive_t = POP(&context, tag_directives_copy)
+//        yaml_free(value.handle)
+//        yaml_free(value.prefix)
+//    }
+//    STACK_DEL(&context, tag_directives_copy)
+//    yaml_free(value.handle)
+//    yaml_free(value.prefix)
+//
+//    return 0
+//}
+//
+///*
+// * Destroy a document object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_document_delete(document *yaml_document_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    tag_directive *yaml_tag_directive_t
+//
+//    context.error = YAML_NO_ERROR // Eliminate a compiler warning.
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    while (!STACK_EMPTY(&context, document.nodes)) {
+//        node yaml_node_t = POP(&context, document.nodes)
+//        yaml_free(node.tag)
+//        switch (node.type) {
+//            case YAML_SCALAR_NODE:
+//                yaml_free(node.data.scalar.value)
+//                break
+//            case YAML_SEQUENCE_NODE:
+//                STACK_DEL(&context, node.data.sequence.items)
+//                break
+//            case YAML_MAPPING_NODE:
+//                STACK_DEL(&context, node.data.mapping.pairs)
+//                break
+//            default:
+//                assert(0) // Should not happen.
+//        }
+//    }
+//    STACK_DEL(&context, document.nodes)
+//
+//    yaml_free(document.version_directive)
+//    for (tag_directive = document.tag_directives.start
+//            tag_directive != document.tag_directives.end
+//            tag_directive++) {
+//        yaml_free(tag_directive.handle)
+//        yaml_free(tag_directive.prefix)
+//    }
+//    yaml_free(document.tag_directives.start)
+//
+//    memset(document, 0, sizeof(yaml_document_t))
+//}
+//
+///**
+// * Get a document node.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_node(document *yaml_document_t, index int)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (index > 0 && document.nodes.start + index <= document.nodes.top) {
+//        return document.nodes.start + index - 1
+//    }
+//    return NULL
+//}
+//
+///**
+// * Get the root object.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_root_node(document *yaml_document_t)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (document.nodes.top != document.nodes.start) {
+//        return document.nodes.start
+//    }
+//    return NULL
+//}
+//
+///*
+// * Add a scalar node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_scalar(document *yaml_document_t,
+//        tag *yaml_char_t, value *yaml_char_t, length int,
+//        style yaml_scalar_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    value_copy *yaml_char_t = NULL
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert(value) // Non-NULL value is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SCALAR_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (length < 0) {
+//        length = strlen((char *)value)
+//    }
+//
+//    if (!yaml_check_utf8(value, length)) goto error
+//    value_copy = yaml_malloc(length+1)
+//    if (!value_copy) goto error
+//    memcpy(value_copy, value, length)
+//    value_copy[length] = '\0'
+//
+//    SCALAR_NODE_INIT(node, tag_copy, value_copy, length, style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    yaml_free(tag_copy)
+//    yaml_free(value_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a sequence node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_sequence(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_sequence_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_item_t
+//        end *yaml_node_item_t
+//        top *yaml_node_item_t
+//    } items = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, items, INITIAL_STACK_SIZE)) goto error
+//
+//    SEQUENCE_NODE_INIT(node, tag_copy, items.start, items.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, items)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a mapping node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_mapping(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_mapping_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_pair_t
+//        end *yaml_node_pair_t
+//        top *yaml_node_pair_t
+//    } pairs = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_MAPPING_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, pairs, INITIAL_STACK_SIZE)) goto error
+//
+//    MAPPING_NODE_INIT(node, tag_copy, pairs.start, pairs.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, pairs)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Append an item to a sequence node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_sequence_item(document *yaml_document_t,
+//        sequence int, item int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(sequence > 0
+//            && document.nodes.start + sequence <= document.nodes.top)
+//                            // Valid sequence id is required.
+//    assert(document.nodes.start[sequence-1].type == YAML_SEQUENCE_NODE)
+//                            // A sequence node is required.
+//    assert(item > 0 && document.nodes.start + item <= document.nodes.top)
+//                            // Valid item id is required.
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[sequence-1].data.sequence.items, item))
+//        return 0
+//
+//    return 1
+//}
+//
+///*
+// * Append a pair of a key and a value to a mapping node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_mapping_pair(document *yaml_document_t,
+//        mapping int, key int, value int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    pair yaml_node_pair_t
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(mapping > 0
+//            && document.nodes.start + mapping <= document.nodes.top)
+//                            // Valid mapping id is required.
+//    assert(document.nodes.start[mapping-1].type == YAML_MAPPING_NODE)
+//                            // A mapping node is required.
+//    assert(key > 0 && document.nodes.start + key <= document.nodes.top)
+//                            // Valid key id is required.
+//    assert(value > 0 && document.nodes.start + value <= document.nodes.top)
+//                            // Valid value id is required.
+//
+//    pair.key = key
+//    pair.value = value
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[mapping-1].data.mapping.pairs, pair))
+//        return 0
+//
+//    return 1
+//}
+//
+//

vendor/gopkg.in/yaml.v2/decode.go

@@ -0,0 +1,815 @@
+package yaml
+
+import (
+	"encoding"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"math"
+	"reflect"
+	"strconv"
+	"time"
+)
+
+const (
+	documentNode = 1 << iota
+	mappingNode
+	sequenceNode
+	scalarNode
+	aliasNode
+)
+
+type node struct {
+	kind         int
+	line, column int
+	tag          string
+	// For an alias node, alias holds the resolved alias.
+	alias    *node
+	value    string
+	implicit bool
+	children []*node
+	anchors  map[string]*node
+}
+
+// ----------------------------------------------------------------------------
+// Parser, produces a node tree out of a libyaml event stream.
+
+type parser struct {
+	parser   yaml_parser_t
+	event    yaml_event_t
+	doc      *node
+	doneInit bool
+}
+
+func newParser(b []byte) *parser {
+	p := parser{}
+	if !yaml_parser_initialize(&p.parser) {
+		panic("failed to initialize YAML emitter")
+	}
+	if len(b) == 0 {
+		b = []byte{'\n'}
+	}
+	yaml_parser_set_input_string(&p.parser, b)
+	return &p
+}
+
+func newParserFromReader(r io.Reader) *parser {
+	p := parser{}
+	if !yaml_parser_initialize(&p.parser) {
+		panic("failed to initialize YAML emitter")
+	}
+	yaml_parser_set_input_reader(&p.parser, r)
+	return &p
+}
+
+func (p *parser) init() {
+	if p.doneInit {
+		return
+	}
+	p.expect(yaml_STREAM_START_EVENT)
+	p.doneInit = true
+}
+
+func (p *parser) destroy() {
+	if p.event.typ != yaml_NO_EVENT {
+		yaml_event_delete(&p.event)
+	}
+	yaml_parser_delete(&p.parser)
+}
+
+// expect consumes an event from the event stream and
+// checks that it's of the expected type.
+func (p *parser) expect(e yaml_event_type_t) {
+	if p.event.typ == yaml_NO_EVENT {
+		if !yaml_parser_parse(&p.parser, &p.event) {
+			p.fail()
+		}
+	}
+	if p.event.typ == yaml_STREAM_END_EVENT {
+		failf("attempted to go past the end of stream; corrupted value?")
+	}
+	if p.event.typ != e {
+		p.parser.problem = fmt.Sprintf("expected %s event but got %s", e, p.event.typ)
+		p.fail()
+	}
+	yaml_event_delete(&p.event)
+	p.event.typ = yaml_NO_EVENT
+}
+
+// peek peeks at the next event in the event stream,
+// puts the results into p.event and returns the event type.
+func (p *parser) peek() yaml_event_type_t {
+	if p.event.typ != yaml_NO_EVENT {
+		return p.event.typ
+	}
+	if !yaml_parser_parse(&p.parser, &p.event) {
+		p.fail()
+	}
+	return p.event.typ
+}
+
+func (p *parser) fail() {
+	var where string
+	var line int
+	if p.parser.problem_mark.line != 0 {
+		line = p.parser.problem_mark.line
+		// Scanner errors don't iterate line before returning error
+		if p.parser.error == yaml_SCANNER_ERROR {
+			line++
+		}
+	} else if p.parser.context_mark.line != 0 {
+		line = p.parser.context_mark.line
+	}
+	if line != 0 {
+		where = "line " + strconv.Itoa(line) + ": "
+	}
+	var msg string
+	if len(p.parser.problem) > 0 {
+		msg = p.parser.problem
+	} else {
+		msg = "unknown problem parsing YAML content"
+	}
+	failf("%s%s", where, msg)
+}
+
+func (p *parser) anchor(n *node, anchor []byte) {
+	if anchor != nil {
+		p.doc.anchors[string(anchor)] = n
+	}
+}
+
+func (p *parser) parse() *node {
+	p.init()
+	switch p.peek() {
+	case yaml_SCALAR_EVENT:
+		return p.scalar()
+	case yaml_ALIAS_EVENT:
+		return p.alias()
+	case yaml_MAPPING_START_EVENT:
+		return p.mapping()
+	case yaml_SEQUENCE_START_EVENT:
+		return p.sequence()
+	case yaml_DOCUMENT_START_EVENT:
+		return p.document()
+	case yaml_STREAM_END_EVENT:
+		// Happens when attempting to decode an empty buffer.
+		return nil
+	default:
+		panic("attempted to parse unknown event: " + p.event.typ.String())
+	}
+}
+
+func (p *parser) node(kind int) *node {
+	return &node{
+		kind:   kind,
+		line:   p.event.start_mark.line,
+		column: p.event.start_mark.column,
+	}
+}
+
+func (p *parser) document() *node {
+	n := p.node(documentNode)
+	n.anchors = make(map[string]*node)
+	p.doc = n
+	p.expect(yaml_DOCUMENT_START_EVENT)
+	n.children = append(n.children, p.parse())
+	p.expect(yaml_DOCUMENT_END_EVENT)
+	return n
+}
+
+func (p *parser) alias() *node {
+	n := p.node(aliasNode)
+	n.value = string(p.event.anchor)
+	n.alias = p.doc.anchors[n.value]
+	if n.alias == nil {
+		failf("unknown anchor '%s' referenced", n.value)
+	}
+	p.expect(yaml_ALIAS_EVENT)
+	return n
+}
+
+func (p *parser) scalar() *node {
+	n := p.node(scalarNode)
+	n.value = string(p.event.value)
+	n.tag = string(p.event.tag)
+	n.implicit = p.event.implicit
+	p.anchor(n, p.event.anchor)
+	p.expect(yaml_SCALAR_EVENT)
+	return n
+}
+
+func (p *parser) sequence() *node {
+	n := p.node(sequenceNode)
+	p.anchor(n, p.event.anchor)
+	p.expect(yaml_SEQUENCE_START_EVENT)
+	for p.peek() != yaml_SEQUENCE_END_EVENT {
+		n.children = append(n.children, p.parse())
+	}
+	p.expect(yaml_SEQUENCE_END_EVENT)
+	return n
+}
+
+func (p *parser) mapping() *node {
+	n := p.node(mappingNode)
+	p.anchor(n, p.event.anchor)
+	p.expect(yaml_MAPPING_START_EVENT)
+	for p.peek() != yaml_MAPPING_END_EVENT {
+		n.children = append(n.children, p.parse(), p.parse())
+	}
+	p.expect(yaml_MAPPING_END_EVENT)
+	return n
+}
+
+// ----------------------------------------------------------------------------
+// Decoder, unmarshals a node into a provided value.
+
+type decoder struct {
+	doc     *node
+	aliases map[*node]bool
+	mapType reflect.Type
+	terrors []string
+	strict  bool
+
+	decodeCount int
+	aliasCount  int
+	aliasDepth  int
+}
+
+var (
+	mapItemType    = reflect.TypeOf(MapItem{})
+	durationType   = reflect.TypeOf(time.Duration(0))
+	defaultMapType = reflect.TypeOf(map[interface{}]interface{}{})
+	ifaceType      = defaultMapType.Elem()
+	timeType       = reflect.TypeOf(time.Time{})
+	ptrTimeType    = reflect.TypeOf(&time.Time{})
+)
+
+func newDecoder(strict bool) *decoder {
+	d := &decoder{mapType: defaultMapType, strict: strict}
+	d.aliases = make(map[*node]bool)
+	return d
+}
+
+func (d *decoder) terror(n *node, tag string, out reflect.Value) {
+	if n.tag != "" {
+		tag = n.tag
+	}
+	value := n.value
+	if tag != yaml_SEQ_TAG && tag != yaml_MAP_TAG {
+		if len(value) > 10 {
+			value = " `" + value[:7] + "...`"
+		} else {
+			value = " `" + value + "`"
+		}
+	}
+	d.terrors = append(d.terrors, fmt.Sprintf("line %d: cannot unmarshal %s%s into %s", n.line+1, shortTag(tag), value, out.Type()))
+}
+
+func (d *decoder) callUnmarshaler(n *node, u Unmarshaler) (good bool) {
+	terrlen := len(d.terrors)
+	err := u.UnmarshalYAML(func(v interface{}) (err error) {
+		defer handleErr(&err)
+		d.unmarshal(n, reflect.ValueOf(v))
+		if len(d.terrors) > terrlen {
+			issues := d.terrors[terrlen:]
+			d.terrors = d.terrors[:terrlen]
+			return &TypeError{issues}
+		}
+		return nil
+	})
+	if e, ok := err.(*TypeError); ok {
+		d.terrors = append(d.terrors, e.Errors...)
+		return false
+	}
+	if err != nil {
+		fail(err)
+	}
+	return true
+}
+
+// d.prepare initializes and dereferences pointers and calls UnmarshalYAML
+// if a value is found to implement it.
+// It returns the initialized and dereferenced out value, whether
+// unmarshalling was already done by UnmarshalYAML, and if so whether
+// its types unmarshalled appropriately.
+//
+// If n holds a null value, prepare returns before doing anything.
+func (d *decoder) prepare(n *node, out reflect.Value) (newout reflect.Value, unmarshaled, good bool) {
+	if n.tag == yaml_NULL_TAG || n.kind == scalarNode && n.tag == "" && (n.value == "null" || n.value == "~" || n.value == "" && n.implicit) {
+		return out, false, false
+	}
+	again := true
+	for again {
+		again = false
+		if out.Kind() == reflect.Ptr {
+			if out.IsNil() {
+				out.Set(reflect.New(out.Type().Elem()))
+			}
+			out = out.Elem()
+			again = true
+		}
+		if out.CanAddr() {
+			if u, ok := out.Addr().Interface().(Unmarshaler); ok {
+				good = d.callUnmarshaler(n, u)
+				return out, true, good
+			}
+		}
+	}
+	return out, false, false
+}
+
+const (
+	// 400,000 decode operations is ~500kb of dense object declarations, or
+	// ~5kb of dense object declarations with 10000% alias expansion
+	alias_ratio_range_low = 400000
+
+	// 4,000,000 decode operations is ~5MB of dense object declarations, or
+	// ~4.5MB of dense object declarations with 10% alias expansion
+	alias_ratio_range_high = 4000000
+
+	// alias_ratio_range is the range over which we scale allowed alias ratios
+	alias_ratio_range = float64(alias_ratio_range_high - alias_ratio_range_low)
+)
+
+func allowedAliasRatio(decodeCount int) float64 {
+	switch {
+	case decodeCount <= alias_ratio_range_low:
+		// allow 99% to come from alias expansion for small-to-medium documents
+		return 0.99
+	case decodeCount >= alias_ratio_range_high:
+		// allow 10% to come from alias expansion for very large documents
+		return 0.10
+	default:
+		// scale smoothly from 99% down to 10% over the range.
+		// this maps to 396,000 - 400,000 allowed alias-driven decodes over the range.
+		// 400,000 decode operations is ~100MB of allocations in worst-case scenarios (single-item maps).
+		return 0.99 - 0.89*(float64(decodeCount-alias_ratio_range_low)/alias_ratio_range)
+	}
+}
+
+func (d *decoder) unmarshal(n *node, out reflect.Value) (good bool) {
+	d.decodeCount++
+	if d.aliasDepth > 0 {
+		d.aliasCount++
+	}
+	if d.aliasCount > 100 && d.decodeCount > 1000 && float64(d.aliasCount)/float64(d.decodeCount) > allowedAliasRatio(d.decodeCount) {
+		failf("document contains excessive aliasing")
+	}
+	switch n.kind {
+	case documentNode:
+		return d.document(n, out)
+	case aliasNode:
+		return d.alias(n, out)
+	}
+	out, unmarshaled, good := d.prepare(n, out)
+	if unmarshaled {
+		return good
+	}
+	switch n.kind {
+	case scalarNode:
+		good = d.scalar(n, out)
+	case mappingNode:
+		good = d.mapping(n, out)
+	case sequenceNode:
+		good = d.sequence(n, out)
+	default:
+		panic("internal error: unknown node kind: " + strconv.Itoa(n.kind))
+	}
+	return good
+}
+
+func (d *decoder) document(n *node, out reflect.Value) (good bool) {
+	if len(n.children) == 1 {
+		d.doc = n
+		d.unmarshal(n.children[0], out)
+		return true
+	}
+	return false
+}
+
+func (d *decoder) alias(n *node, out reflect.Value) (good bool) {
+	if d.aliases[n] {
+		// TODO this could actually be allowed in some circumstances.
+		failf("anchor '%s' value contains itself", n.value)
+	}
+	d.aliases[n] = true
+	d.aliasDepth++
+	good = d.unmarshal(n.alias, out)
+	d.aliasDepth--
+	delete(d.aliases, n)
+	return good
+}
+
+var zeroValue reflect.Value
+
+func resetMap(out reflect.Value) {
+	for _, k := range out.MapKeys() {
+		out.SetMapIndex(k, zeroValue)
+	}
+}
+
+func (d *decoder) scalar(n *node, out reflect.Value) bool {
+	var tag string
+	var resolved interface{}
+	if n.tag == "" && !n.implicit {
+		tag = yaml_STR_TAG
+		resolved = n.value
+	} else {
+		tag, resolved = resolve(n.tag, n.value)
+		if tag == yaml_BINARY_TAG {
+			data, err := base64.StdEncoding.DecodeString(resolved.(string))
+			if err != nil {
+				failf("!!binary value contains invalid base64 data")
+			}
+			resolved = string(data)
+		}
+	}
+	if resolved == nil {
+		if out.Kind() == reflect.Map && !out.CanAddr() {
+			resetMap(out)
+		} else {
+			out.Set(reflect.Zero(out.Type()))
+		}
+		return true
+	}
+	if resolvedv := reflect.ValueOf(resolved); out.Type() == resolvedv.Type() {
+		// We've resolved to exactly the type we want, so use that.
+		out.Set(resolvedv)
+		return true
+	}
+	// Perhaps we can use the value as a TextUnmarshaler to
+	// set its value.
+	if out.CanAddr() {
+		u, ok := out.Addr().Interface().(encoding.TextUnmarshaler)
+		if ok {
+			var text []byte
+			if tag == yaml_BINARY_TAG {
+				text = []byte(resolved.(string))
+			} else {
+				// We let any value be unmarshaled into TextUnmarshaler.
+				// That might be more lax than we'd like, but the
+				// TextUnmarshaler itself should bowl out any dubious values.
+				text = []byte(n.value)
+			}
+			err := u.UnmarshalText(text)
+			if err != nil {
+				fail(err)
+			}
+			return true
+		}
+	}
+	switch out.Kind() {
+	case reflect.String:
+		if tag == yaml_BINARY_TAG {
+			out.SetString(resolved.(string))
+			return true
+		}
+		if resolved != nil {
+			out.SetString(n.value)
+			return true
+		}
+	case reflect.Interface:
+		if resolved == nil {
+			out.Set(reflect.Zero(out.Type()))
+		} else if tag == yaml_TIMESTAMP_TAG {
+			// It looks like a timestamp but for backward compatibility
+			// reasons we set it as a string, so that code that unmarshals
+			// timestamp-like values into interface{} will continue to
+			// see a string and not a time.Time.
+			// TODO(v3) Drop this.
+			out.Set(reflect.ValueOf(n.value))
+		} else {
+			out.Set(reflect.ValueOf(resolved))
+		}
+		return true
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		switch resolved := resolved.(type) {
+		case int:
+			if !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				return true
+			}
+		case int64:
+			if !out.OverflowInt(resolved) {
+				out.SetInt(resolved)
+				return true
+			}
+		case uint64:
+			if resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				return true
+			}
+		case float64:
+			if resolved <= math.MaxInt64 && !out.OverflowInt(int64(resolved)) {
+				out.SetInt(int64(resolved))
+				return true
+			}
+		case string:
+			if out.Type() == durationType {
+				d, err := time.ParseDuration(resolved)
+				if err == nil {
+					out.SetInt(int64(d))
+					return true
+				}
+			}
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		switch resolved := resolved.(type) {
+		case int:
+			if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				return true
+			}
+		case int64:
+			if resolved >= 0 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				return true
+			}
+		case uint64:
+			if !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				return true
+			}
+		case float64:
+			if resolved <= math.MaxUint64 && !out.OverflowUint(uint64(resolved)) {
+				out.SetUint(uint64(resolved))
+				return true
+			}
+		}
+	case reflect.Bool:
+		switch resolved := resolved.(type) {
+		case bool:
+			out.SetBool(resolved)
+			return true
+		}
+	case reflect.Float32, reflect.Float64:
+		switch resolved := resolved.(type) {
+		case int:
+			out.SetFloat(float64(resolved))
+			return true
+		case int64:
+			out.SetFloat(float64(resolved))
+			return true
+		case uint64:
+			out.SetFloat(float64(resolved))
+			return true
+		case float64:
+			out.SetFloat(resolved)
+			return true
+		}
+	case reflect.Struct:
+		if resolvedv := reflect.ValueOf(resolved); out.Type() == resolvedv.Type() {
+			out.Set(resolvedv)
+			return true
+		}
+	case reflect.Ptr:
+		if out.Type().Elem() == reflect.TypeOf(resolved) {
+			// TODO DOes this make sense? When is out a Ptr except when decoding a nil value?
+			elem := reflect.New(out.Type().Elem())
+			elem.Elem().Set(reflect.ValueOf(resolved))
+			out.Set(elem)
+			return true
+		}
+	}
+	d.terror(n, tag, out)
+	return false
+}
+
+func settableValueOf(i interface{}) reflect.Value {
+	v := reflect.ValueOf(i)
+	sv := reflect.New(v.Type()).Elem()
+	sv.Set(v)
+	return sv
+}
+
+func (d *decoder) sequence(n *node, out reflect.Value) (good bool) {
+	l := len(n.children)
+
+	var iface reflect.Value
+	switch out.Kind() {
+	case reflect.Slice:
+		out.Set(reflect.MakeSlice(out.Type(), l, l))
+	case reflect.Array:
+		if l != out.Len() {
+			failf("invalid array: want %d elements but got %d", out.Len(), l)
+		}
+	case reflect.Interface:
+		// No type hints. Will have to use a generic sequence.
+		iface = out
+		out = settableValueOf(make([]interface{}, l))
+	default:
+		d.terror(n, yaml_SEQ_TAG, out)
+		return false
+	}
+	et := out.Type().Elem()
+
+	j := 0
+	for i := 0; i < l; i++ {
+		e := reflect.New(et).Elem()
+		if ok := d.unmarshal(n.children[i], e); ok {
+			out.Index(j).Set(e)
+			j++
+		}
+	}
+	if out.Kind() != reflect.Array {
+		out.Set(out.Slice(0, j))
+	}
+	if iface.IsValid() {
+		iface.Set(out)
+	}
+	return true
+}
+
+func (d *decoder) mapping(n *node, out reflect.Value) (good bool) {
+	switch out.Kind() {
+	case reflect.Struct:
+		return d.mappingStruct(n, out)
+	case reflect.Slice:
+		return d.mappingSlice(n, out)
+	case reflect.Map:
+		// okay
+	case reflect.Interface:
+		if d.mapType.Kind() == reflect.Map {
+			iface := out
+			out = reflect.MakeMap(d.mapType)
+			iface.Set(out)
+		} else {
+			slicev := reflect.New(d.mapType).Elem()
+			if !d.mappingSlice(n, slicev) {
+				return false
+			}
+			out.Set(slicev)
+			return true
+		}
+	default:
+		d.terror(n, yaml_MAP_TAG, out)
+		return false
+	}
+	outt := out.Type()
+	kt := outt.Key()
+	et := outt.Elem()
+
+	mapType := d.mapType
+	if outt.Key() == ifaceType && outt.Elem() == ifaceType {
+		d.mapType = outt
+	}
+
+	if out.IsNil() {
+		out.Set(reflect.MakeMap(outt))
+	}
+	l := len(n.children)
+	for i := 0; i < l; i += 2 {
+		if isMerge(n.children[i]) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		k := reflect.New(kt).Elem()
+		if d.unmarshal(n.children[i], k) {
+			kkind := k.Kind()
+			if kkind == reflect.Interface {
+				kkind = k.Elem().Kind()
+			}
+			if kkind == reflect.Map || kkind == reflect.Slice {
+				failf("invalid map key: %#v", k.Interface())
+			}
+			e := reflect.New(et).Elem()
+			if d.unmarshal(n.children[i+1], e) {
+				d.setMapIndex(n.children[i+1], out, k, e)
+			}
+		}
+	}
+	d.mapType = mapType
+	return true
+}
+
+func (d *decoder) setMapIndex(n *node, out, k, v reflect.Value) {
+	if d.strict && out.MapIndex(k) != zeroValue {
+		d.terrors = append(d.terrors, fmt.Sprintf("line %d: key %#v already set in map", n.line+1, k.Interface()))
+		return
+	}
+	out.SetMapIndex(k, v)
+}
+
+func (d *decoder) mappingSlice(n *node, out reflect.Value) (good bool) {
+	outt := out.Type()
+	if outt.Elem() != mapItemType {
+		d.terror(n, yaml_MAP_TAG, out)
+		return false
+	}
+
+	mapType := d.mapType
+	d.mapType = outt
+
+	var slice []MapItem
+	var l = len(n.children)
+	for i := 0; i < l; i += 2 {
+		if isMerge(n.children[i]) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		item := MapItem{}
+		k := reflect.ValueOf(&item.Key).Elem()
+		if d.unmarshal(n.children[i], k) {
+			v := reflect.ValueOf(&item.Value).Elem()
+			if d.unmarshal(n.children[i+1], v) {
+				slice = append(slice, item)
+			}
+		}
+	}
+	out.Set(reflect.ValueOf(slice))
+	d.mapType = mapType
+	return true
+}
+
+func (d *decoder) mappingStruct(n *node, out reflect.Value) (good bool) {
+	sinfo, err := getStructInfo(out.Type())
+	if err != nil {
+		panic(err)
+	}
+	name := settableValueOf("")
+	l := len(n.children)
+
+	var inlineMap reflect.Value
+	var elemType reflect.Type
+	if sinfo.InlineMap != -1 {
+		inlineMap = out.Field(sinfo.InlineMap)
+		inlineMap.Set(reflect.New(inlineMap.Type()).Elem())
+		elemType = inlineMap.Type().Elem()
+	}
+
+	var doneFields []bool
+	if d.strict {
+		doneFields = make([]bool, len(sinfo.FieldsList))
+	}
+	for i := 0; i < l; i += 2 {
+		ni := n.children[i]
+		if isMerge(ni) {
+			d.merge(n.children[i+1], out)
+			continue
+		}
+		if !d.unmarshal(ni, name) {
+			continue
+		}
+		if info, ok := sinfo.FieldsMap[name.String()]; ok {
+			if d.strict {
+				if doneFields[info.Id] {
+					d.terrors = append(d.terrors, fmt.Sprintf("line %d: field %s already set in type %s", ni.line+1, name.String(), out.Type()))
+					continue
+				}
+				doneFields[info.Id] = true
+			}
+			var field reflect.Value
+			if info.Inline == nil {
+				field = out.Field(info.Num)
+			} else {
+				field = out.FieldByIndex(info.Inline)
+			}
+			d.unmarshal(n.children[i+1], field)
+		} else if sinfo.InlineMap != -1 {
+			if inlineMap.IsNil() {
+				inlineMap.Set(reflect.MakeMap(inlineMap.Type()))
+			}
+			value := reflect.New(elemType).Elem()
+			d.unmarshal(n.children[i+1], value)
+			d.setMapIndex(n.children[i+1], inlineMap, name, value)
+		} else if d.strict {
+			d.terrors = append(d.terrors, fmt.Sprintf("line %d: field %s not found in type %s", ni.line+1, name.String(), out.Type()))
+		}
+	}
+	return true
+}
+
+func failWantMap() {
+	failf("map merge requires map or sequence of maps as the value")
+}
+
+func (d *decoder) merge(n *node, out reflect.Value) {
+	switch n.kind {
+	case mappingNode:
+		d.unmarshal(n, out)
+	case aliasNode:
+		if n.alias != nil && n.alias.kind != mappingNode {
+			failWantMap()
+		}
+		d.unmarshal(n, out)
+	case sequenceNode:
+		// Step backwards as earlier nodes take precedence.
+		for i := len(n.children) - 1; i >= 0; i-- {
+			ni := n.children[i]
+			if ni.kind == aliasNode {
+				if ni.alias != nil && ni.alias.kind != mappingNode {
+					failWantMap()
+				}
+			} else if ni.kind != mappingNode {
+				failWantMap()
+			}
+			d.unmarshal(ni, out)
+		}
+	default:
+		failWantMap()
+	}
+}
+
+func isMerge(n *node) bool {
+	return n.kind == scalarNode && n.value == "<<" && (n.implicit == true || n.tag == yaml_MERGE_TAG)
+}

vendor/gopkg.in/yaml.v2/encode.go

@@ -0,0 +1,390 @@
+package yaml
+
+import (
+	"encoding"
+	"fmt"
+	"io"
+	"reflect"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
+
+// jsonNumber is the interface of the encoding/json.Number datatype.
+// Repeating the interface here avoids a dependency on encoding/json, and also
+// supports other libraries like jsoniter, which use a similar datatype with
+// the same interface. Detecting this interface is useful when dealing with
+// structures containing json.Number, which is a string under the hood. The
+// encoder should prefer the use of Int64(), Float64() and string(), in that
+// order, when encoding this type.
+type jsonNumber interface {
+	Float64() (float64, error)
+	Int64() (int64, error)
+	String() string
+}
+
+type encoder struct {
+	emitter yaml_emitter_t
+	event   yaml_event_t
+	out     []byte
+	flow    bool
+	// doneInit holds whether the initial stream_start_event has been
+	// emitted.
+	doneInit bool
+}
+
+func newEncoder() *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_string(&e.emitter, &e.out)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func newEncoderWithWriter(w io.Writer) *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_writer(&e.emitter, w)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func (e *encoder) init() {
+	if e.doneInit {
+		return
+	}
+	yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING)
+	e.emit()
+	e.doneInit = true
+}
+
+func (e *encoder) finish() {
+	e.emitter.open_ended = false
+	yaml_stream_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) destroy() {
+	yaml_emitter_delete(&e.emitter)
+}
+
+func (e *encoder) emit() {
+	// This will internally delete the e.event value.
+	e.must(yaml_emitter_emit(&e.emitter, &e.event))
+}
+
+func (e *encoder) must(ok bool) {
+	if !ok {
+		msg := e.emitter.problem
+		if msg == "" {
+			msg = "unknown problem generating YAML content"
+		}
+		failf("%s", msg)
+	}
+}
+
+func (e *encoder) marshalDoc(tag string, in reflect.Value) {
+	e.init()
+	yaml_document_start_event_initialize(&e.event, nil, nil, true)
+	e.emit()
+	e.marshal(tag, in)
+	yaml_document_end_event_initialize(&e.event, true)
+	e.emit()
+}
+
+func (e *encoder) marshal(tag string, in reflect.Value) {
+	if !in.IsValid() || in.Kind() == reflect.Ptr && in.IsNil() {
+		e.nilv()
+		return
+	}
+	iface := in.Interface()
+	switch m := iface.(type) {
+	case jsonNumber:
+		integer, err := m.Int64()
+		if err == nil {
+			// In this case the json.Number is a valid int64
+			in = reflect.ValueOf(integer)
+			break
+		}
+		float, err := m.Float64()
+		if err == nil {
+			// In this case the json.Number is a valid float64
+			in = reflect.ValueOf(float)
+			break
+		}
+		// fallback case - no number could be obtained
+		in = reflect.ValueOf(m.String())
+	case time.Time, *time.Time:
+		// Although time.Time implements TextMarshaler,
+		// we don't want to treat it as a string for YAML
+		// purposes because YAML has special support for
+		// timestamps.
+	case Marshaler:
+		v, err := m.MarshalYAML()
+		if err != nil {
+			fail(err)
+		}
+		if v == nil {
+			e.nilv()
+			return
+		}
+		in = reflect.ValueOf(v)
+	case encoding.TextMarshaler:
+		text, err := m.MarshalText()
+		if err != nil {
+			fail(err)
+		}
+		in = reflect.ValueOf(string(text))
+	case nil:
+		e.nilv()
+		return
+	}
+	switch in.Kind() {
+	case reflect.Interface:
+		e.marshal(tag, in.Elem())
+	case reflect.Map:
+		e.mapv(tag, in)
+	case reflect.Ptr:
+		if in.Type() == ptrTimeType {
+			e.timev(tag, in.Elem())
+		} else {
+			e.marshal(tag, in.Elem())
+		}
+	case reflect.Struct:
+		if in.Type() == timeType {
+			e.timev(tag, in)
+		} else {
+			e.structv(tag, in)
+		}
+	case reflect.Slice, reflect.Array:
+		if in.Type().Elem() == mapItemType {
+			e.itemsv(tag, in)
+		} else {
+			e.slicev(tag, in)
+		}
+	case reflect.String:
+		e.stringv(tag, in)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		if in.Type() == durationType {
+			e.stringv(tag, reflect.ValueOf(iface.(time.Duration).String()))
+		} else {
+			e.intv(tag, in)
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		e.uintv(tag, in)
+	case reflect.Float32, reflect.Float64:
+		e.floatv(tag, in)
+	case reflect.Bool:
+		e.boolv(tag, in)
+	default:
+		panic("cannot marshal type: " + in.Type().String())
+	}
+}
+
+func (e *encoder) mapv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		keys := keyList(in.MapKeys())
+		sort.Sort(keys)
+		for _, k := range keys {
+			e.marshal("", k)
+			e.marshal("", in.MapIndex(k))
+		}
+	})
+}
+
+func (e *encoder) itemsv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		slice := in.Convert(reflect.TypeOf([]MapItem{})).Interface().([]MapItem)
+		for _, item := range slice {
+			e.marshal("", reflect.ValueOf(item.Key))
+			e.marshal("", reflect.ValueOf(item.Value))
+		}
+	})
+}
+
+func (e *encoder) structv(tag string, in reflect.Value) {
+	sinfo, err := getStructInfo(in.Type())
+	if err != nil {
+		panic(err)
+	}
+	e.mappingv(tag, func() {
+		for _, info := range sinfo.FieldsList {
+			var value reflect.Value
+			if info.Inline == nil {
+				value = in.Field(info.Num)
+			} else {
+				value = in.FieldByIndex(info.Inline)
+			}
+			if info.OmitEmpty && isZero(value) {
+				continue
+			}
+			e.marshal("", reflect.ValueOf(info.Key))
+			e.flow = info.Flow
+			e.marshal("", value)
+		}
+		if sinfo.InlineMap >= 0 {
+			m := in.Field(sinfo.InlineMap)
+			if m.Len() > 0 {
+				e.flow = false
+				keys := keyList(m.MapKeys())
+				sort.Sort(keys)
+				for _, k := range keys {
+					if _, found := sinfo.FieldsMap[k.String()]; found {
+						panic(fmt.Sprintf("Can't have key %q in inlined map; conflicts with struct field", k.String()))
+					}
+					e.marshal("", k)
+					e.flow = false
+					e.marshal("", m.MapIndex(k))
+				}
+			}
+		}
+	})
+}
+
+func (e *encoder) mappingv(tag string, f func()) {
+	implicit := tag == ""
+	style := yaml_BLOCK_MAPPING_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_MAPPING_STYLE
+	}
+	yaml_mapping_start_event_initialize(&e.event, nil, []byte(tag), implicit, style)
+	e.emit()
+	f()
+	yaml_mapping_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) slicev(tag string, in reflect.Value) {
+	implicit := tag == ""
+	style := yaml_BLOCK_SEQUENCE_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_SEQUENCE_STYLE
+	}
+	e.must(yaml_sequence_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
+	e.emit()
+	n := in.Len()
+	for i := 0; i < n; i++ {
+		e.marshal("", in.Index(i))
+	}
+	e.must(yaml_sequence_end_event_initialize(&e.event))
+	e.emit()
+}
+
+// isBase60 returns whether s is in base 60 notation as defined in YAML 1.1.
+//
+// The base 60 float notation in YAML 1.1 is a terrible idea and is unsupported
+// in YAML 1.2 and by this package, but these should be marshalled quoted for
+// the time being for compatibility with other parsers.
+func isBase60Float(s string) (result bool) {
+	// Fast path.
+	if s == "" {
+		return false
+	}
+	c := s[0]
+	if !(c == '+' || c == '-' || c >= '0' && c <= '9') || strings.IndexByte(s, ':') < 0 {
+		return false
+	}
+	// Do the full match.
+	return base60float.MatchString(s)
+}
+
+// From http://yaml.org/type/float.html, except the regular expression there
+// is bogus. In practice parsers do not enforce the "\.[0-9_]*" suffix.
+var base60float = regexp.MustCompile(`^[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+(?:\.[0-9_]*)?$`)
+
+func (e *encoder) stringv(tag string, in reflect.Value) {
+	var style yaml_scalar_style_t
+	s := in.String()
+	canUsePlain := true
+	switch {
+	case !utf8.ValidString(s):
+		if tag == yaml_BINARY_TAG {
+			failf("explicitly tagged !!binary data must be base64-encoded")
+		}
+		if tag != "" {
+			failf("cannot marshal invalid UTF-8 data as %s", shortTag(tag))
+		}
+		// It can't be encoded directly as YAML so use a binary tag
+		// and encode it as base64.
+		tag = yaml_BINARY_TAG
+		s = encodeBase64(s)
+	case tag == "":
+		// Check to see if it would resolve to a specific
+		// tag when encoded unquoted. If it doesn't,
+		// there's no need to quote it.
+		rtag, _ := resolve("", s)
+		canUsePlain = rtag == yaml_STR_TAG && !isBase60Float(s)
+	}
+	// Note: it's possible for user code to emit invalid YAML
+	// if they explicitly specify a tag and a string containing
+	// text that's incompatible with that tag.
+	switch {
+	case strings.Contains(s, "\n"):
+		style = yaml_LITERAL_SCALAR_STYLE
+	case canUsePlain:
+		style = yaml_PLAIN_SCALAR_STYLE
+	default:
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+	e.emitScalar(s, "", tag, style)
+}
+
+func (e *encoder) boolv(tag string, in reflect.Value) {
+	var s string
+	if in.Bool() {
+		s = "true"
+	} else {
+		s = "false"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) intv(tag string, in reflect.Value) {
+	s := strconv.FormatInt(in.Int(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) uintv(tag string, in reflect.Value) {
+	s := strconv.FormatUint(in.Uint(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) timev(tag string, in reflect.Value) {
+	t := in.Interface().(time.Time)
+	s := t.Format(time.RFC3339Nano)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) floatv(tag string, in reflect.Value) {
+	// Issue #352: When formatting, use the precision of the underlying value
+	precision := 64
+	if in.Kind() == reflect.Float32 {
+		precision = 32
+	}
+
+	s := strconv.FormatFloat(in.Float(), 'g', -1, precision)
+	switch s {
+	case "+Inf":
+		s = ".inf"
+	case "-Inf":
+		s = "-.inf"
+	case "NaN":
+		s = ".nan"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) nilv() {
+	e.emitScalar("null", "", "", yaml_PLAIN_SCALAR_STYLE)
+}
+
+func (e *encoder) emitScalar(value, anchor, tag string, style yaml_scalar_style_t) {
+	implicit := tag == ""
+	e.must(yaml_scalar_event_initialize(&e.event, []byte(anchor), []byte(tag), []byte(value), implicit, implicit, style))
+	e.emit()
+}

vendor/gopkg.in/yaml.v2/readerc.go

@@ -0,0 +1,412 @@
+package yaml
+
+import (
+	"io"
+)
+
+// Set the reader error and return 0.
+func yaml_parser_set_reader_error(parser *yaml_parser_t, problem string, offset int, value int) bool {
+	parser.error = yaml_READER_ERROR
+	parser.problem = problem
+	parser.problem_offset = offset
+	parser.problem_value = value
+	return false
+}
+
+// Byte order marks.
+const (
+	bom_UTF8    = "\xef\xbb\xbf"
+	bom_UTF16LE = "\xff\xfe"
+	bom_UTF16BE = "\xfe\xff"
+)
+
+// Determine the input stream encoding by checking the BOM symbol. If no BOM is
+// found, the UTF-8 encoding is assumed. Return 1 on success, 0 on failure.
+func yaml_parser_determine_encoding(parser *yaml_parser_t) bool {
+	// Ensure that we had enough bytes in the raw buffer.
+	for !parser.eof && len(parser.raw_buffer)-parser.raw_buffer_pos < 3 {
+		if !yaml_parser_update_raw_buffer(parser) {
+			return false
+		}
+	}
+
+	// Determine the encoding.
+	buf := parser.raw_buffer
+	pos := parser.raw_buffer_pos
+	avail := len(buf) - pos
+	if avail >= 2 && buf[pos] == bom_UTF16LE[0] && buf[pos+1] == bom_UTF16LE[1] {
+		parser.encoding = yaml_UTF16LE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 2 && buf[pos] == bom_UTF16BE[0] && buf[pos+1] == bom_UTF16BE[1] {
+		parser.encoding = yaml_UTF16BE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 3 && buf[pos] == bom_UTF8[0] && buf[pos+1] == bom_UTF8[1] && buf[pos+2] == bom_UTF8[2] {
+		parser.encoding = yaml_UTF8_ENCODING
+		parser.raw_buffer_pos += 3
+		parser.offset += 3
+	} else {
+		parser.encoding = yaml_UTF8_ENCODING
+	}
+	return true
+}
+
+// Update the raw buffer.
+func yaml_parser_update_raw_buffer(parser *yaml_parser_t) bool {
+	size_read := 0
+
+	// Return if the raw buffer is full.
+	if parser.raw_buffer_pos == 0 && len(parser.raw_buffer) == cap(parser.raw_buffer) {
+		return true
+	}
+
+	// Return on EOF.
+	if parser.eof {
+		return true
+	}
+
+	// Move the remaining bytes in the raw buffer to the beginning.
+	if parser.raw_buffer_pos > 0 && parser.raw_buffer_pos < len(parser.raw_buffer) {
+		copy(parser.raw_buffer, parser.raw_buffer[parser.raw_buffer_pos:])
+	}
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)-parser.raw_buffer_pos]
+	parser.raw_buffer_pos = 0
+
+	// Call the read handler to fill the buffer.
+	size_read, err := parser.read_handler(parser, parser.raw_buffer[len(parser.raw_buffer):cap(parser.raw_buffer)])
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)+size_read]
+	if err == io.EOF {
+		parser.eof = true
+	} else if err != nil {
+		return yaml_parser_set_reader_error(parser, "input error: "+err.Error(), parser.offset, -1)
+	}
+	return true
+}
+
+// Ensure that the buffer contains at least `length` characters.
+// Return true on success, false on failure.
+//
+// The length is supposed to be significantly less that the buffer size.
+func yaml_parser_update_buffer(parser *yaml_parser_t, length int) bool {
+	if parser.read_handler == nil {
+		panic("read handler must be set")
+	}
+
+	// [Go] This function was changed to guarantee the requested length size at EOF.
+	// The fact we need to do this is pretty awful, but the description above implies
+	// for that to be the case, and there are tests 
+
+	// If the EOF flag is set and the raw buffer is empty, do nothing.
+	if parser.eof && parser.raw_buffer_pos == len(parser.raw_buffer) {
+		// [Go] ACTUALLY! Read the documentation of this function above.
+		// This is just broken. To return true, we need to have the
+		// given length in the buffer. Not doing that means every single
+		// check that calls this function to make sure the buffer has a
+		// given length is Go) panicking; or C) accessing invalid memory.
+		//return true
+	}
+
+	// Return if the buffer contains enough characters.
+	if parser.unread >= length {
+		return true
+	}
+
+	// Determine the input encoding if it is not known yet.
+	if parser.encoding == yaml_ANY_ENCODING {
+		if !yaml_parser_determine_encoding(parser) {
+			return false
+		}
+	}
+
+	// Move the unread characters to the beginning of the buffer.
+	buffer_len := len(parser.buffer)
+	if parser.buffer_pos > 0 && parser.buffer_pos < buffer_len {
+		copy(parser.buffer, parser.buffer[parser.buffer_pos:])
+		buffer_len -= parser.buffer_pos
+		parser.buffer_pos = 0
+	} else if parser.buffer_pos == buffer_len {
+		buffer_len = 0
+		parser.buffer_pos = 0
+	}
+
+	// Open the whole buffer for writing, and cut it before returning.
+	parser.buffer = parser.buffer[:cap(parser.buffer)]
+
+	// Fill the buffer until it has enough characters.
+	first := true
+	for parser.unread < length {
+
+		// Fill the raw buffer if necessary.
+		if !first || parser.raw_buffer_pos == len(parser.raw_buffer) {
+			if !yaml_parser_update_raw_buffer(parser) {
+				parser.buffer = parser.buffer[:buffer_len]
+				return false
+			}
+		}
+		first = false
+
+		// Decode the raw buffer.
+	inner:
+		for parser.raw_buffer_pos != len(parser.raw_buffer) {
+			var value rune
+			var width int
+
+			raw_unread := len(parser.raw_buffer) - parser.raw_buffer_pos
+
+			// Decode the next character.
+			switch parser.encoding {
+			case yaml_UTF8_ENCODING:
+				// Decode a UTF-8 character.  Check RFC 3629
+				// (http://www.ietf.org/rfc/rfc3629.txt) for more details.
+				//
+				// The following table (taken from the RFC) is used for
+				// decoding.
+				//
+				//    Char. number range |        UTF-8 octet sequence
+				//      (hexadecimal)    |              (binary)
+				//   --------------------+------------------------------------
+				//   0000 0000-0000 007F | 0xxxxxxx
+				//   0000 0080-0000 07FF | 110xxxxx 10xxxxxx
+				//   0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
+				//   0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				//
+				// Additionally, the characters in the range 0xD800-0xDFFF
+				// are prohibited as they are reserved for use with UTF-16
+				// surrogate pairs.
+
+				// Determine the length of the UTF-8 sequence.
+				octet := parser.raw_buffer[parser.raw_buffer_pos]
+				switch {
+				case octet&0x80 == 0x00:
+					width = 1
+				case octet&0xE0 == 0xC0:
+					width = 2
+				case octet&0xF0 == 0xE0:
+					width = 3
+				case octet&0xF8 == 0xF0:
+					width = 4
+				default:
+					// The leading octet is invalid.
+					return yaml_parser_set_reader_error(parser,
+						"invalid leading UTF-8 octet",
+						parser.offset, int(octet))
+				}
+
+				// Check if the raw buffer contains an incomplete character.
+				if width > raw_unread {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-8 octet sequence",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Decode the leading octet.
+				switch {
+				case octet&0x80 == 0x00:
+					value = rune(octet & 0x7F)
+				case octet&0xE0 == 0xC0:
+					value = rune(octet & 0x1F)
+				case octet&0xF0 == 0xE0:
+					value = rune(octet & 0x0F)
+				case octet&0xF8 == 0xF0:
+					value = rune(octet & 0x07)
+				default:
+					value = 0
+				}
+
+				// Check and decode the trailing octets.
+				for k := 1; k < width; k++ {
+					octet = parser.raw_buffer[parser.raw_buffer_pos+k]
+
+					// Check if the octet is valid.
+					if (octet & 0xC0) != 0x80 {
+						return yaml_parser_set_reader_error(parser,
+							"invalid trailing UTF-8 octet",
+							parser.offset+k, int(octet))
+					}
+
+					// Decode the octet.
+					value = (value << 6) + rune(octet&0x3F)
+				}
+
+				// Check the length of the sequence against the value.
+				switch {
+				case width == 1:
+				case width == 2 && value >= 0x80:
+				case width == 3 && value >= 0x800:
+				case width == 4 && value >= 0x10000:
+				default:
+					return yaml_parser_set_reader_error(parser,
+						"invalid length of a UTF-8 sequence",
+						parser.offset, -1)
+				}
+
+				// Check the range of the value.
+				if value >= 0xD800 && value <= 0xDFFF || value > 0x10FFFF {
+					return yaml_parser_set_reader_error(parser,
+						"invalid Unicode character",
+						parser.offset, int(value))
+				}
+
+			case yaml_UTF16LE_ENCODING, yaml_UTF16BE_ENCODING:
+				var low, high int
+				if parser.encoding == yaml_UTF16LE_ENCODING {
+					low, high = 0, 1
+				} else {
+					low, high = 1, 0
+				}
+
+				// The UTF-16 encoding is not as simple as one might
+				// naively think.  Check RFC 2781
+				// (http://www.ietf.org/rfc/rfc2781.txt).
+				//
+				// Normally, two subsequent bytes describe a Unicode
+				// character.  However a special technique (called a
+				// surrogate pair) is used for specifying character
+				// values larger than 0xFFFF.
+				//
+				// A surrogate pair consists of two pseudo-characters:
+				//      high surrogate area (0xD800-0xDBFF)
+				//      low surrogate area (0xDC00-0xDFFF)
+				//
+				// The following formulas are used for decoding
+				// and encoding characters using surrogate pairs:
+				//
+				//  U  = U' + 0x10000   (0x01 00 00 <= U <= 0x10 FF FF)
+				//  U' = yyyyyyyyyyxxxxxxxxxx   (0 <= U' <= 0x0F FF FF)
+				//  W1 = 110110yyyyyyyyyy
+				//  W2 = 110111xxxxxxxxxx
+				//
+				// where U is the character value, W1 is the high surrogate
+				// area, W2 is the low surrogate area.
+
+				// Check for incomplete UTF-16 character.
+				if raw_unread < 2 {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-16 character",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Get the character.
+				value = rune(parser.raw_buffer[parser.raw_buffer_pos+low]) +
+					(rune(parser.raw_buffer[parser.raw_buffer_pos+high]) << 8)
+
+				// Check for unexpected low surrogate area.
+				if value&0xFC00 == 0xDC00 {
+					return yaml_parser_set_reader_error(parser,
+						"unexpected low surrogate area",
+						parser.offset, int(value))
+				}
+
+				// Check for a high surrogate area.
+				if value&0xFC00 == 0xD800 {
+					width = 4
+
+					// Check for incomplete surrogate pair.
+					if raw_unread < 4 {
+						if parser.eof {
+							return yaml_parser_set_reader_error(parser,
+								"incomplete UTF-16 surrogate pair",
+								parser.offset, -1)
+						}
+						break inner
+					}
+
+					// Get the next character.
+					value2 := rune(parser.raw_buffer[parser.raw_buffer_pos+low+2]) +
+						(rune(parser.raw_buffer[parser.raw_buffer_pos+high+2]) << 8)
+
+					// Check for a low surrogate area.
+					if value2&0xFC00 != 0xDC00 {
+						return yaml_parser_set_reader_error(parser,
+							"expected low surrogate area",
+							parser.offset+2, int(value2))
+					}
+
+					// Generate the value of the surrogate pair.
+					value = 0x10000 + ((value & 0x3FF) << 10) + (value2 & 0x3FF)
+				} else {
+					width = 2
+				}
+
+			default:
+				panic("impossible")
+			}
+
+			// Check if the character is in the allowed range:
+			//      #x9 | #xA | #xD | [#x20-#x7E]               (8 bit)
+			//      | #x85 | [#xA0-#xD7FF] | [#xE000-#xFFFD]    (16 bit)
+			//      | [#x10000-#x10FFFF]                        (32 bit)
+			switch {
+			case value == 0x09:
+			case value == 0x0A:
+			case value == 0x0D:
+			case value >= 0x20 && value <= 0x7E:
+			case value == 0x85:
+			case value >= 0xA0 && value <= 0xD7FF:
+			case value >= 0xE000 && value <= 0xFFFD:
+			case value >= 0x10000 && value <= 0x10FFFF:
+			default:
+				return yaml_parser_set_reader_error(parser,
+					"control characters are not allowed",
+					parser.offset, int(value))
+			}
+
+			// Move the raw pointers.
+			parser.raw_buffer_pos += width
+			parser.offset += width
+
+			// Finally put the character into the buffer.
+			if value <= 0x7F {
+				// 0000 0000-0000 007F . 0xxxxxxx
+				parser.buffer[buffer_len+0] = byte(value)
+				buffer_len += 1
+			} else if value <= 0x7FF {
+				// 0000 0080-0000 07FF . 110xxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xC0 + (value >> 6))
+				parser.buffer[buffer_len+1] = byte(0x80 + (value & 0x3F))
+				buffer_len += 2
+			} else if value <= 0xFFFF {
+				// 0000 0800-0000 FFFF . 1110xxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xE0 + (value >> 12))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + (value & 0x3F))
+				buffer_len += 3
+			} else {
+				// 0001 0000-0010 FFFF . 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xF0 + (value >> 18))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 12) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+3] = byte(0x80 + (value & 0x3F))
+				buffer_len += 4
+			}
+
+			parser.unread++
+		}
+
+		// On EOF, put NUL into the buffer and return.
+		if parser.eof {
+			parser.buffer[buffer_len] = 0
+			buffer_len++
+			parser.unread++
+			break
+		}
+	}
+	// [Go] Read the documentation of this function above. To return true,
+	// we need to have the given length in the buffer. Not doing that means
+	// every single check that calls this function to make sure the buffer
+	// has a given length is Go) panicking; or C) accessing invalid memory.
+	// This happens here due to the EOF above breaking early.
+	for buffer_len < length {
+		parser.buffer[buffer_len] = 0
+		buffer_len++
+	}
+	parser.buffer = parser.buffer[:buffer_len]
+	return true
+}

vendor/gopkg.in/yaml.v2/resolve.go

@@ -0,0 +1,258 @@
+package yaml
+
+import (
+	"encoding/base64"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type resolveMapItem struct {
+	value interface{}
+	tag   string
+}
+
+var resolveTable = make([]byte, 256)
+var resolveMap = make(map[string]resolveMapItem)
+
+func init() {
+	t := resolveTable
+	t[int('+')] = 'S' // Sign
+	t[int('-')] = 'S'
+	for _, c := range "0123456789" {
+		t[int(c)] = 'D' // Digit
+	}
+	for _, c := range "yYnNtTfFoO~" {
+		t[int(c)] = 'M' // In map
+	}
+	t[int('.')] = '.' // Float (potentially in map)
+
+	var resolveMapList = []struct {
+		v   interface{}
+		tag string
+		l   []string
+	}{
+		{true, yaml_BOOL_TAG, []string{"y", "Y", "yes", "Yes", "YES"}},
+		{true, yaml_BOOL_TAG, []string{"true", "True", "TRUE"}},
+		{true, yaml_BOOL_TAG, []string{"on", "On", "ON"}},
+		{false, yaml_BOOL_TAG, []string{"n", "N", "no", "No", "NO"}},
+		{false, yaml_BOOL_TAG, []string{"false", "False", "FALSE"}},
+		{false, yaml_BOOL_TAG, []string{"off", "Off", "OFF"}},
+		{nil, yaml_NULL_TAG, []string{"", "~", "null", "Null", "NULL"}},
+		{math.NaN(), yaml_FLOAT_TAG, []string{".nan", ".NaN", ".NAN"}},
+		{math.Inf(+1), yaml_FLOAT_TAG, []string{".inf", ".Inf", ".INF"}},
+		{math.Inf(+1), yaml_FLOAT_TAG, []string{"+.inf", "+.Inf", "+.INF"}},
+		{math.Inf(-1), yaml_FLOAT_TAG, []string{"-.inf", "-.Inf", "-.INF"}},
+		{"<<", yaml_MERGE_TAG, []string{"<<"}},
+	}
+
+	m := resolveMap
+	for _, item := range resolveMapList {
+		for _, s := range item.l {
+			m[s] = resolveMapItem{item.v, item.tag}
+		}
+	}
+}
+
+const longTagPrefix = "tag:yaml.org,2002:"
+
+func shortTag(tag string) string {
+	// TODO This can easily be made faster and produce less garbage.
+	if strings.HasPrefix(tag, longTagPrefix) {
+		return "!!" + tag[len(longTagPrefix):]
+	}
+	return tag
+}
+
+func longTag(tag string) string {
+	if strings.HasPrefix(tag, "!!") {
+		return longTagPrefix + tag[2:]
+	}
+	return tag
+}
+
+func resolvableTag(tag string) bool {
+	switch tag {
+	case "", yaml_STR_TAG, yaml_BOOL_TAG, yaml_INT_TAG, yaml_FLOAT_TAG, yaml_NULL_TAG, yaml_TIMESTAMP_TAG:
+		return true
+	}
+	return false
+}
+
+var yamlStyleFloat = regexp.MustCompile(`^[-+]?(\.[0-9]+|[0-9]+(\.[0-9]*)?)([eE][-+]?[0-9]+)?$`)
+
+func resolve(tag string, in string) (rtag string, out interface{}) {
+	if !resolvableTag(tag) {
+		return tag, in
+	}
+
+	defer func() {
+		switch tag {
+		case "", rtag, yaml_STR_TAG, yaml_BINARY_TAG:
+			return
+		case yaml_FLOAT_TAG:
+			if rtag == yaml_INT_TAG {
+				switch v := out.(type) {
+				case int64:
+					rtag = yaml_FLOAT_TAG
+					out = float64(v)
+					return
+				case int:
+					rtag = yaml_FLOAT_TAG
+					out = float64(v)
+					return
+				}
+			}
+		}
+		failf("cannot decode %s `%s` as a %s", shortTag(rtag), in, shortTag(tag))
+	}()
+
+	// Any data is accepted as a !!str or !!binary.
+	// Otherwise, the prefix is enough of a hint about what it might be.
+	hint := byte('N')
+	if in != "" {
+		hint = resolveTable[in[0]]
+	}
+	if hint != 0 && tag != yaml_STR_TAG && tag != yaml_BINARY_TAG {
+		// Handle things we can lookup in a map.
+		if item, ok := resolveMap[in]; ok {
+			return item.tag, item.value
+		}
+
+		// Base 60 floats are a bad idea, were dropped in YAML 1.2, and
+		// are purposefully unsupported here. They're still quoted on
+		// the way out for compatibility with other parser, though.
+
+		switch hint {
+		case 'M':
+			// We've already checked the map above.
+
+		case '.':
+			// Not in the map, so maybe a normal float.
+			floatv, err := strconv.ParseFloat(in, 64)
+			if err == nil {
+				return yaml_FLOAT_TAG, floatv
+			}
+
+		case 'D', 'S':
+			// Int, float, or timestamp.
+			// Only try values as a timestamp if the value is unquoted or there's an explicit
+			// !!timestamp tag.
+			if tag == "" || tag == yaml_TIMESTAMP_TAG {
+				t, ok := parseTimestamp(in)
+				if ok {
+					return yaml_TIMESTAMP_TAG, t
+				}
+			}
+
+			plain := strings.Replace(in, "_", "", -1)
+			intv, err := strconv.ParseInt(plain, 0, 64)
+			if err == nil {
+				if intv == int64(int(intv)) {
+					return yaml_INT_TAG, int(intv)
+				} else {
+					return yaml_INT_TAG, intv
+				}
+			}
+			uintv, err := strconv.ParseUint(plain, 0, 64)
+			if err == nil {
+				return yaml_INT_TAG, uintv
+			}
+			if yamlStyleFloat.MatchString(plain) {
+				floatv, err := strconv.ParseFloat(plain, 64)
+				if err == nil {
+					return yaml_FLOAT_TAG, floatv
+				}
+			}
+			if strings.HasPrefix(plain, "0b") {
+				intv, err := strconv.ParseInt(plain[2:], 2, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return yaml_INT_TAG, int(intv)
+					} else {
+						return yaml_INT_TAG, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 2, 64)
+				if err == nil {
+					return yaml_INT_TAG, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0b") {
+				intv, err := strconv.ParseInt("-" + plain[3:], 2, 64)
+				if err == nil {
+					if true || intv == int64(int(intv)) {
+						return yaml_INT_TAG, int(intv)
+					} else {
+						return yaml_INT_TAG, intv
+					}
+				}
+			}
+		default:
+			panic("resolveTable item not yet handled: " + string(rune(hint)) + " (with " + in + ")")
+		}
+	}
+	return yaml_STR_TAG, in
+}
+
+// encodeBase64 encodes s as base64 that is broken up into multiple lines
+// as appropriate for the resulting length.
+func encodeBase64(s string) string {
+	const lineLen = 70
+	encLen := base64.StdEncoding.EncodedLen(len(s))
+	lines := encLen/lineLen + 1
+	buf := make([]byte, encLen*2+lines)
+	in := buf[0:encLen]
+	out := buf[encLen:]
+	base64.StdEncoding.Encode(in, []byte(s))
+	k := 0
+	for i := 0; i < len(in); i += lineLen {
+		j := i + lineLen
+		if j > len(in) {
+			j = len(in)
+		}
+		k += copy(out[k:], in[i:j])
+		if lines > 1 {
+			out[k] = '\n'
+			k++
+		}
+	}
+	return string(out[:k])
+}
+
+// This is a subset of the formats allowed by the regular expression
+// defined at http://yaml.org/type/timestamp.html.
+var allowedTimestampFormats = []string{
+	"2006-1-2T15:4:5.999999999Z07:00", // RCF3339Nano with short date fields.
+	"2006-1-2t15:4:5.999999999Z07:00", // RFC3339Nano with short date fields and lower-case "t".
+	"2006-1-2 15:4:5.999999999",       // space separated with no time zone
+	"2006-1-2",                        // date only
+	// Notable exception: time.Parse cannot handle: "2001-12-14 21:59:43.10 -5"
+	// from the set of examples.
+}
+
+// parseTimestamp parses s as a timestamp string and
+// returns the timestamp and reports whether it succeeded.
+// Timestamp formats are defined at http://yaml.org/type/timestamp.html
+func parseTimestamp(s string) (time.Time, bool) {
+	// TODO write code to check all the formats supported by
+	// http://yaml.org/type/timestamp.html instead of using time.Parse.
+
+	// Quick check: all date formats start with YYYY-.
+	i := 0
+	for ; i < len(s); i++ {
+		if c := s[i]; c < '0' || c > '9' {
+			break
+		}
+	}
+	if i != 4 || i == len(s) || s[i] != '-' {
+		return time.Time{}, false
+	}
+	for _, format := range allowedTimestampFormats {
+		if t, err := time.Parse(format, s); err == nil {
+			return t, true
+		}
+	}
+	return time.Time{}, false
+}

vendor/gopkg.in/yaml.v2/sorter.go

@@ -0,0 +1,113 @@
+package yaml
+
+import (
+	"reflect"
+	"unicode"
+)
+
+type keyList []reflect.Value
+
+func (l keyList) Len() int      { return len(l) }
+func (l keyList) Swap(i, j int) { l[i], l[j] = l[j], l[i] }
+func (l keyList) Less(i, j int) bool {
+	a := l[i]
+	b := l[j]
+	ak := a.Kind()
+	bk := b.Kind()
+	for (ak == reflect.Interface || ak == reflect.Ptr) && !a.IsNil() {
+		a = a.Elem()
+		ak = a.Kind()
+	}
+	for (bk == reflect.Interface || bk == reflect.Ptr) && !b.IsNil() {
+		b = b.Elem()
+		bk = b.Kind()
+	}
+	af, aok := keyFloat(a)
+	bf, bok := keyFloat(b)
+	if aok && bok {
+		if af != bf {
+			return af < bf
+		}
+		if ak != bk {
+			return ak < bk
+		}
+		return numLess(a, b)
+	}
+	if ak != reflect.String || bk != reflect.String {
+		return ak < bk
+	}
+	ar, br := []rune(a.String()), []rune(b.String())
+	for i := 0; i < len(ar) && i < len(br); i++ {
+		if ar[i] == br[i] {
+			continue
+		}
+		al := unicode.IsLetter(ar[i])
+		bl := unicode.IsLetter(br[i])
+		if al && bl {
+			return ar[i] < br[i]
+		}
+		if al || bl {
+			return bl
+		}
+		var ai, bi int
+		var an, bn int64
+		if ar[i] == '0' || br[i] == '0' {
+			for j := i-1; j >= 0 && unicode.IsDigit(ar[j]); j-- {
+				if ar[j] != '0' {
+					an = 1
+					bn = 1
+					break
+				}
+			}
+		}
+		for ai = i; ai < len(ar) && unicode.IsDigit(ar[ai]); ai++ {
+			an = an*10 + int64(ar[ai]-'0')
+		}
+		for bi = i; bi < len(br) && unicode.IsDigit(br[bi]); bi++ {
+			bn = bn*10 + int64(br[bi]-'0')
+		}
+		if an != bn {
+			return an < bn
+		}
+		if ai != bi {
+			return ai < bi
+		}
+		return ar[i] < br[i]
+	}
+	return len(ar) < len(br)
+}
+
+// keyFloat returns a float value for v if it is a number/bool
+// and whether it is a number/bool or not.
+func keyFloat(v reflect.Value) (f float64, ok bool) {
+	switch v.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return float64(v.Int()), true
+	case reflect.Float32, reflect.Float64:
+		return v.Float(), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return float64(v.Uint()), true
+	case reflect.Bool:
+		if v.Bool() {
+			return 1, true
+		}
+		return 0, true
+	}
+	return 0, false
+}
+
+// numLess returns whether a < b.
+// a and b must necessarily have the same kind.
+func numLess(a, b reflect.Value) bool {
+	switch a.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return a.Int() < b.Int()
+	case reflect.Float32, reflect.Float64:
+		return a.Float() < b.Float()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return a.Uint() < b.Uint()
+	case reflect.Bool:
+		return !a.Bool() && b.Bool()
+	}
+	panic("not a number")
+}

vendor/gopkg.in/yaml.v2/writerc.go

@@ -0,0 +1,26 @@
+package yaml
+
+// Set the writer error and return false.
+func yaml_emitter_set_writer_error(emitter *yaml_emitter_t, problem string) bool {
+	emitter.error = yaml_WRITER_ERROR
+	emitter.problem = problem
+	return false
+}
+
+// Flush the output buffer.
+func yaml_emitter_flush(emitter *yaml_emitter_t) bool {
+	if emitter.write_handler == nil {
+		panic("write handler not set")
+	}
+
+	// Check if the buffer is empty.
+	if emitter.buffer_pos == 0 {
+		return true
+	}
+
+	if err := emitter.write_handler(emitter, emitter.buffer[:emitter.buffer_pos]); err != nil {
+		return yaml_emitter_set_writer_error(emitter, "write error: "+err.Error())
+	}
+	emitter.buffer_pos = 0
+	return true
+}

vendor/gopkg.in/yaml.v2/yaml.go

@@ -0,0 +1,466 @@
+// Package yaml implements YAML support for the Go language.
+//
+// Source code and other details for the project are available at GitHub:
+//
+//   https://github.com/go-yaml/yaml
+//
+package yaml
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+	"sync"
+)
+
+// MapSlice encodes and decodes as a YAML map.
+// The order of keys is preserved when encoding and decoding.
+type MapSlice []MapItem
+
+// MapItem is an item in a MapSlice.
+type MapItem struct {
+	Key, Value interface{}
+}
+
+// The Unmarshaler interface may be implemented by types to customize their
+// behavior when being unmarshaled from a YAML document. The UnmarshalYAML
+// method receives a function that may be called to unmarshal the original
+// YAML value into a field or variable. It is safe to call the unmarshal
+// function parameter more than once if necessary.
+type Unmarshaler interface {
+	UnmarshalYAML(unmarshal func(interface{}) error) error
+}
+
+// The Marshaler interface may be implemented by types to customize their
+// behavior when being marshaled into a YAML document. The returned value
+// is marshaled in place of the original value implementing Marshaler.
+//
+// If an error is returned by MarshalYAML, the marshaling procedure stops
+// and returns with the provided error.
+type Marshaler interface {
+	MarshalYAML() (interface{}, error)
+}
+
+// Unmarshal decodes the first document found within the in byte slice
+// and assigns decoded values into the out value.
+//
+// Maps and pointers (to a struct, string, int, etc) are accepted as out
+// values. If an internal pointer within a struct is not initialized,
+// the yaml package will initialize it if necessary for unmarshalling
+// the provided data. The out parameter must not be nil.
+//
+// The type of the decoded values should be compatible with the respective
+// values in out. If one or more values cannot be decoded due to a type
+// mismatches, decoding continues partially until the end of the YAML
+// content, and a *yaml.TypeError is returned with details for all
+// missed values.
+//
+// Struct fields are only unmarshalled if they are exported (have an
+// upper case first letter), and are unmarshalled using the field name
+// lowercased as the default key. Custom keys may be defined via the
+// "yaml" name in the field tag: the content preceding the first comma
+// is used as the key, and the following comma-separated options are
+// used to tweak the marshalling process (see Marshal).
+// Conflicting names result in a runtime error.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     var t T
+//     yaml.Unmarshal([]byte("a: 1\nb: 2"), &t)
+//
+// See the documentation of Marshal for the format of tags and a list of
+// supported tag options.
+//
+func Unmarshal(in []byte, out interface{}) (err error) {
+	return unmarshal(in, out, false)
+}
+
+// UnmarshalStrict is like Unmarshal except that any fields that are found
+// in the data that do not have corresponding struct members, or mapping
+// keys that are duplicates, will result in
+// an error.
+func UnmarshalStrict(in []byte, out interface{}) (err error) {
+	return unmarshal(in, out, true)
+}
+
+// A Decoder reads and decodes YAML values from an input stream.
+type Decoder struct {
+	strict bool
+	parser *parser
+}
+
+// NewDecoder returns a new decoder that reads from r.
+//
+// The decoder introduces its own buffering and may read
+// data from r beyond the YAML values requested.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{
+		parser: newParserFromReader(r),
+	}
+}
+
+// SetStrict sets whether strict decoding behaviour is enabled when
+// decoding items in the data (see UnmarshalStrict). By default, decoding is not strict.
+func (dec *Decoder) SetStrict(strict bool) {
+	dec.strict = strict
+}
+
+// Decode reads the next YAML-encoded value from its input
+// and stores it in the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (dec *Decoder) Decode(v interface{}) (err error) {
+	d := newDecoder(dec.strict)
+	defer handleErr(&err)
+	node := dec.parser.parse()
+	if node == nil {
+		return io.EOF
+	}
+	out := reflect.ValueOf(v)
+	if out.Kind() == reflect.Ptr && !out.IsNil() {
+		out = out.Elem()
+	}
+	d.unmarshal(node, out)
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+func unmarshal(in []byte, out interface{}, strict bool) (err error) {
+	defer handleErr(&err)
+	d := newDecoder(strict)
+	p := newParser(in)
+	defer p.destroy()
+	node := p.parse()
+	if node != nil {
+		v := reflect.ValueOf(out)
+		if v.Kind() == reflect.Ptr && !v.IsNil() {
+			v = v.Elem()
+		}
+		d.unmarshal(node, v)
+	}
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Marshal serializes the value provided into a YAML document. The structure
+// of the generated document will reflect the structure of the value itself.
+// Maps and pointers (to struct, string, int, etc) are accepted as the in value.
+//
+// Struct fields are only marshalled if they are exported (have an upper case
+// first letter), and are marshalled using the field name lowercased as the
+// default key. Custom keys may be defined via the "yaml" name in the field
+// tag: the content preceding the first comma is used as the key, and the
+// following comma-separated options are used to tweak the marshalling process.
+// Conflicting names result in a runtime error.
+//
+// The field tag format accepted is:
+//
+//     `(...) yaml:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported:
+//
+//     omitempty    Only include the field if it's not set to the zero
+//                  value for the type or to empty slices or maps.
+//                  Zero valued structs will be omitted if all their public
+//                  fields are zero, unless they implement an IsZero
+//                  method (see the IsZeroer interface type), in which
+//                  case the field will be included if that method returns true.
+//
+//     flow         Marshal using a flow style (useful for structs,
+//                  sequences and maps).
+//
+//     inline       Inline the field, which must be a struct or a map,
+//                  causing all of its fields or keys to be processed as if
+//                  they were part of the outer struct. For maps, keys must
+//                  not conflict with the yaml keys of other struct fields.
+//
+// In addition, if the key is "-", the field is ignored.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     yaml.Marshal(&T{B: 2}) // Returns "b: 2\n"
+//     yaml.Marshal(&T{F: 1}} // Returns "a: 1\nb: 0\n"
+//
+func Marshal(in interface{}) (out []byte, err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshalDoc("", reflect.ValueOf(in))
+	e.finish()
+	out = e.out
+	return
+}
+
+// An Encoder writes YAML values to an output stream.
+type Encoder struct {
+	encoder *encoder
+}
+
+// NewEncoder returns a new encoder that writes to w.
+// The Encoder should be closed after use to flush all data
+// to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		encoder: newEncoderWithWriter(w),
+	}
+}
+
+// Encode writes the YAML encoding of v to the stream.
+// If multiple items are encoded to the stream, the
+// second and subsequent document will be preceded
+// with a "---" document separator, but the first will not.
+//
+// See the documentation for Marshal for details about the conversion of Go
+// values to YAML.
+func (e *Encoder) Encode(v interface{}) (err error) {
+	defer handleErr(&err)
+	e.encoder.marshalDoc("", reflect.ValueOf(v))
+	return nil
+}
+
+// Close closes the encoder by writing any remaining data.
+// It does not write a stream terminating string "...".
+func (e *Encoder) Close() (err error) {
+	defer handleErr(&err)
+	e.encoder.finish()
+	return nil
+}
+
+func handleErr(err *error) {
+	if v := recover(); v != nil {
+		if e, ok := v.(yamlError); ok {
+			*err = e.err
+		} else {
+			panic(v)
+		}
+	}
+}
+
+type yamlError struct {
+	err error
+}
+
+func fail(err error) {
+	panic(yamlError{err})
+}
+
+func failf(format string, args ...interface{}) {
+	panic(yamlError{fmt.Errorf("yaml: "+format, args...)})
+}
+
+// A TypeError is returned by Unmarshal when one or more fields in
+// the YAML document cannot be properly decoded into the requested
+// types. When this error is returned, the value is still
+// unmarshaled partially.
+type TypeError struct {
+	Errors []string
+}
+
+func (e *TypeError) Error() string {
+	return fmt.Sprintf("yaml: unmarshal errors:\n  %s", strings.Join(e.Errors, "\n  "))
+}
+
+// --------------------------------------------------------------------------
+// Maintain a mapping of keys to structure field indexes
+
+// The code in this section was copied from mgo/bson.
+
+// structInfo holds details for the serialization of fields of
+// a given struct.
+type structInfo struct {
+	FieldsMap  map[string]fieldInfo
+	FieldsList []fieldInfo
+
+	// InlineMap is the number of the field in the struct that
+	// contains an ,inline map, or -1 if there's none.
+	InlineMap int
+}
+
+type fieldInfo struct {
+	Key       string
+	Num       int
+	OmitEmpty bool
+	Flow      bool
+	// Id holds the unique field identifier, so we can cheaply
+	// check for field duplicates without maintaining an extra map.
+	Id int
+
+	// Inline holds the field index if the field is part of an inlined struct.
+	Inline []int
+}
+
+var structMap = make(map[reflect.Type]*structInfo)
+var fieldMapMutex sync.RWMutex
+
+func getStructInfo(st reflect.Type) (*structInfo, error) {
+	fieldMapMutex.RLock()
+	sinfo, found := structMap[st]
+	fieldMapMutex.RUnlock()
+	if found {
+		return sinfo, nil
+	}
+
+	n := st.NumField()
+	fieldsMap := make(map[string]fieldInfo)
+	fieldsList := make([]fieldInfo, 0, n)
+	inlineMap := -1
+	for i := 0; i != n; i++ {
+		field := st.Field(i)
+		if field.PkgPath != "" && !field.Anonymous {
+			continue // Private field
+		}
+
+		info := fieldInfo{Num: i}
+
+		tag := field.Tag.Get("yaml")
+		if tag == "" && strings.Index(string(field.Tag), ":") < 0 {
+			tag = string(field.Tag)
+		}
+		if tag == "-" {
+			continue
+		}
+
+		inline := false
+		fields := strings.Split(tag, ",")
+		if len(fields) > 1 {
+			for _, flag := range fields[1:] {
+				switch flag {
+				case "omitempty":
+					info.OmitEmpty = true
+				case "flow":
+					info.Flow = true
+				case "inline":
+					inline = true
+				default:
+					return nil, errors.New(fmt.Sprintf("Unsupported flag %q in tag %q of type %s", flag, tag, st))
+				}
+			}
+			tag = fields[0]
+		}
+
+		if inline {
+			switch field.Type.Kind() {
+			case reflect.Map:
+				if inlineMap >= 0 {
+					return nil, errors.New("Multiple ,inline maps in struct " + st.String())
+				}
+				if field.Type.Key() != reflect.TypeOf("") {
+					return nil, errors.New("Option ,inline needs a map with string keys in struct " + st.String())
+				}
+				inlineMap = info.Num
+			case reflect.Struct:
+				sinfo, err := getStructInfo(field.Type)
+				if err != nil {
+					return nil, err
+				}
+				for _, finfo := range sinfo.FieldsList {
+					if _, found := fieldsMap[finfo.Key]; found {
+						msg := "Duplicated key '" + finfo.Key + "' in struct " + st.String()
+						return nil, errors.New(msg)
+					}
+					if finfo.Inline == nil {
+						finfo.Inline = []int{i, finfo.Num}
+					} else {
+						finfo.Inline = append([]int{i}, finfo.Inline...)
+					}
+					finfo.Id = len(fieldsList)
+					fieldsMap[finfo.Key] = finfo
+					fieldsList = append(fieldsList, finfo)
+				}
+			default:
+				//return nil, errors.New("Option ,inline needs a struct value or map field")
+				return nil, errors.New("Option ,inline needs a struct value field")
+			}
+			continue
+		}
+
+		if tag != "" {
+			info.Key = tag
+		} else {
+			info.Key = strings.ToLower(field.Name)
+		}
+
+		if _, found = fieldsMap[info.Key]; found {
+			msg := "Duplicated key '" + info.Key + "' in struct " + st.String()
+			return nil, errors.New(msg)
+		}
+
+		info.Id = len(fieldsList)
+		fieldsList = append(fieldsList, info)
+		fieldsMap[info.Key] = info
+	}
+
+	sinfo = &structInfo{
+		FieldsMap:  fieldsMap,
+		FieldsList: fieldsList,
+		InlineMap:  inlineMap,
+	}
+
+	fieldMapMutex.Lock()
+	structMap[st] = sinfo
+	fieldMapMutex.Unlock()
+	return sinfo, nil
+}
+
+// IsZeroer is used to check whether an object is zero to
+// determine whether it should be omitted when marshaling
+// with the omitempty flag. One notable implementation
+// is time.Time.
+type IsZeroer interface {
+	IsZero() bool
+}
+
+func isZero(v reflect.Value) bool {
+	kind := v.Kind()
+	if z, ok := v.Interface().(IsZeroer); ok {
+		if (kind == reflect.Ptr || kind == reflect.Interface) && v.IsNil() {
+			return true
+		}
+		return z.IsZero()
+	}
+	switch kind {
+	case reflect.String:
+		return len(v.String()) == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	case reflect.Slice:
+		return v.Len() == 0
+	case reflect.Map:
+		return v.Len() == 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Struct:
+		vt := v.Type()
+		for i := v.NumField() - 1; i >= 0; i-- {
+			if vt.Field(i).PkgPath != "" {
+				continue // Private field
+			}
+			if !isZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}

vendor/gopkg.in/yaml.v2/yamlh.go

@@ -0,0 +1,739 @@
+package yaml
+
+import (
+	"fmt"
+	"io"
+)
+
+// The version directive data.
+type yaml_version_directive_t struct {
+	major int8 // The major version number.
+	minor int8 // The minor version number.
+}
+
+// The tag directive data.
+type yaml_tag_directive_t struct {
+	handle []byte // The tag handle.
+	prefix []byte // The tag prefix.
+}
+
+type yaml_encoding_t int
+
+// The stream encoding.
+const (
+	// Let the parser choose the encoding.
+	yaml_ANY_ENCODING yaml_encoding_t = iota
+
+	yaml_UTF8_ENCODING    // The default UTF-8 encoding.
+	yaml_UTF16LE_ENCODING // The UTF-16-LE encoding with BOM.
+	yaml_UTF16BE_ENCODING // The UTF-16-BE encoding with BOM.
+)
+
+type yaml_break_t int
+
+// Line break types.
+const (
+	// Let the parser choose the break type.
+	yaml_ANY_BREAK yaml_break_t = iota
+
+	yaml_CR_BREAK   // Use CR for line breaks (Mac style).
+	yaml_LN_BREAK   // Use LN for line breaks (Unix style).
+	yaml_CRLN_BREAK // Use CR LN for line breaks (DOS style).
+)
+
+type yaml_error_type_t int
+
+// Many bad things could happen with the parser and emitter.
+const (
+	// No error is produced.
+	yaml_NO_ERROR yaml_error_type_t = iota
+
+	yaml_MEMORY_ERROR   // Cannot allocate or reallocate a block of memory.
+	yaml_READER_ERROR   // Cannot read or decode the input stream.
+	yaml_SCANNER_ERROR  // Cannot scan the input stream.
+	yaml_PARSER_ERROR   // Cannot parse the input stream.
+	yaml_COMPOSER_ERROR // Cannot compose a YAML document.
+	yaml_WRITER_ERROR   // Cannot write to the output stream.
+	yaml_EMITTER_ERROR  // Cannot emit a YAML stream.
+)
+
+// The pointer position.
+type yaml_mark_t struct {
+	index  int // The position index.
+	line   int // The position line.
+	column int // The position column.
+}
+
+// Node Styles
+
+type yaml_style_t int8
+
+type yaml_scalar_style_t yaml_style_t
+
+// Scalar styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SCALAR_STYLE yaml_scalar_style_t = iota
+
+	yaml_PLAIN_SCALAR_STYLE         // The plain scalar style.
+	yaml_SINGLE_QUOTED_SCALAR_STYLE // The single-quoted scalar style.
+	yaml_DOUBLE_QUOTED_SCALAR_STYLE // The double-quoted scalar style.
+	yaml_LITERAL_SCALAR_STYLE       // The literal scalar style.
+	yaml_FOLDED_SCALAR_STYLE        // The folded scalar style.
+)
+
+type yaml_sequence_style_t yaml_style_t
+
+// Sequence styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SEQUENCE_STYLE yaml_sequence_style_t = iota
+
+	yaml_BLOCK_SEQUENCE_STYLE // The block sequence style.
+	yaml_FLOW_SEQUENCE_STYLE  // The flow sequence style.
+)
+
+type yaml_mapping_style_t yaml_style_t
+
+// Mapping styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_MAPPING_STYLE yaml_mapping_style_t = iota
+
+	yaml_BLOCK_MAPPING_STYLE // The block mapping style.
+	yaml_FLOW_MAPPING_STYLE  // The flow mapping style.
+)
+
+// Tokens
+
+type yaml_token_type_t int
+
+// Token types.
+const (
+	// An empty token.
+	yaml_NO_TOKEN yaml_token_type_t = iota
+
+	yaml_STREAM_START_TOKEN // A STREAM-START token.
+	yaml_STREAM_END_TOKEN   // A STREAM-END token.
+
+	yaml_VERSION_DIRECTIVE_TOKEN // A VERSION-DIRECTIVE token.
+	yaml_TAG_DIRECTIVE_TOKEN     // A TAG-DIRECTIVE token.
+	yaml_DOCUMENT_START_TOKEN    // A DOCUMENT-START token.
+	yaml_DOCUMENT_END_TOKEN      // A DOCUMENT-END token.
+
+	yaml_BLOCK_SEQUENCE_START_TOKEN // A BLOCK-SEQUENCE-START token.
+	yaml_BLOCK_MAPPING_START_TOKEN  // A BLOCK-SEQUENCE-END token.
+	yaml_BLOCK_END_TOKEN            // A BLOCK-END token.
+
+	yaml_FLOW_SEQUENCE_START_TOKEN // A FLOW-SEQUENCE-START token.
+	yaml_FLOW_SEQUENCE_END_TOKEN   // A FLOW-SEQUENCE-END token.
+	yaml_FLOW_MAPPING_START_TOKEN  // A FLOW-MAPPING-START token.
+	yaml_FLOW_MAPPING_END_TOKEN    // A FLOW-MAPPING-END token.
+
+	yaml_BLOCK_ENTRY_TOKEN // A BLOCK-ENTRY token.
+	yaml_FLOW_ENTRY_TOKEN  // A FLOW-ENTRY token.
+	yaml_KEY_TOKEN         // A KEY token.
+	yaml_VALUE_TOKEN       // A VALUE token.
+
+	yaml_ALIAS_TOKEN  // An ALIAS token.
+	yaml_ANCHOR_TOKEN // An ANCHOR token.
+	yaml_TAG_TOKEN    // A TAG token.
+	yaml_SCALAR_TOKEN // A SCALAR token.
+)
+
+func (tt yaml_token_type_t) String() string {
+	switch tt {
+	case yaml_NO_TOKEN:
+		return "yaml_NO_TOKEN"
+	case yaml_STREAM_START_TOKEN:
+		return "yaml_STREAM_START_TOKEN"
+	case yaml_STREAM_END_TOKEN:
+		return "yaml_STREAM_END_TOKEN"
+	case yaml_VERSION_DIRECTIVE_TOKEN:
+		return "yaml_VERSION_DIRECTIVE_TOKEN"
+	case yaml_TAG_DIRECTIVE_TOKEN:
+		return "yaml_TAG_DIRECTIVE_TOKEN"
+	case yaml_DOCUMENT_START_TOKEN:
+		return "yaml_DOCUMENT_START_TOKEN"
+	case yaml_DOCUMENT_END_TOKEN:
+		return "yaml_DOCUMENT_END_TOKEN"
+	case yaml_BLOCK_SEQUENCE_START_TOKEN:
+		return "yaml_BLOCK_SEQUENCE_START_TOKEN"
+	case yaml_BLOCK_MAPPING_START_TOKEN:
+		return "yaml_BLOCK_MAPPING_START_TOKEN"
+	case yaml_BLOCK_END_TOKEN:
+		return "yaml_BLOCK_END_TOKEN"
+	case yaml_FLOW_SEQUENCE_START_TOKEN:
+		return "yaml_FLOW_SEQUENCE_START_TOKEN"
+	case yaml_FLOW_SEQUENCE_END_TOKEN:
+		return "yaml_FLOW_SEQUENCE_END_TOKEN"
+	case yaml_FLOW_MAPPING_START_TOKEN:
+		return "yaml_FLOW_MAPPING_START_TOKEN"
+	case yaml_FLOW_MAPPING_END_TOKEN:
+		return "yaml_FLOW_MAPPING_END_TOKEN"
+	case yaml_BLOCK_ENTRY_TOKEN:
+		return "yaml_BLOCK_ENTRY_TOKEN"
+	case yaml_FLOW_ENTRY_TOKEN:
+		return "yaml_FLOW_ENTRY_TOKEN"
+	case yaml_KEY_TOKEN:
+		return "yaml_KEY_TOKEN"
+	case yaml_VALUE_TOKEN:
+		return "yaml_VALUE_TOKEN"
+	case yaml_ALIAS_TOKEN:
+		return "yaml_ALIAS_TOKEN"
+	case yaml_ANCHOR_TOKEN:
+		return "yaml_ANCHOR_TOKEN"
+	case yaml_TAG_TOKEN:
+		return "yaml_TAG_TOKEN"
+	case yaml_SCALAR_TOKEN:
+		return "yaml_SCALAR_TOKEN"
+	}
+	return "<unknown token>"
+}
+
+// The token structure.
+type yaml_token_t struct {
+	// The token type.
+	typ yaml_token_type_t
+
+	// The start/end of the token.
+	start_mark, end_mark yaml_mark_t
+
+	// The stream encoding (for yaml_STREAM_START_TOKEN).
+	encoding yaml_encoding_t
+
+	// The alias/anchor/scalar value or tag/tag directive handle
+	// (for yaml_ALIAS_TOKEN, yaml_ANCHOR_TOKEN, yaml_SCALAR_TOKEN, yaml_TAG_TOKEN, yaml_TAG_DIRECTIVE_TOKEN).
+	value []byte
+
+	// The tag suffix (for yaml_TAG_TOKEN).
+	suffix []byte
+
+	// The tag directive prefix (for yaml_TAG_DIRECTIVE_TOKEN).
+	prefix []byte
+
+	// The scalar style (for yaml_SCALAR_TOKEN).
+	style yaml_scalar_style_t
+
+	// The version directive major/minor (for yaml_VERSION_DIRECTIVE_TOKEN).
+	major, minor int8
+}
+
+// Events
+
+type yaml_event_type_t int8
+
+// Event types.
+const (
+	// An empty event.
+	yaml_NO_EVENT yaml_event_type_t = iota
+
+	yaml_STREAM_START_EVENT   // A STREAM-START event.
+	yaml_STREAM_END_EVENT     // A STREAM-END event.
+	yaml_DOCUMENT_START_EVENT // A DOCUMENT-START event.
+	yaml_DOCUMENT_END_EVENT   // A DOCUMENT-END event.
+	yaml_ALIAS_EVENT          // An ALIAS event.
+	yaml_SCALAR_EVENT         // A SCALAR event.
+	yaml_SEQUENCE_START_EVENT // A SEQUENCE-START event.
+	yaml_SEQUENCE_END_EVENT   // A SEQUENCE-END event.
+	yaml_MAPPING_START_EVENT  // A MAPPING-START event.
+	yaml_MAPPING_END_EVENT    // A MAPPING-END event.
+)
+
+var eventStrings = []string{
+	yaml_NO_EVENT:             "none",
+	yaml_STREAM_START_EVENT:   "stream start",
+	yaml_STREAM_END_EVENT:     "stream end",
+	yaml_DOCUMENT_START_EVENT: "document start",
+	yaml_DOCUMENT_END_EVENT:   "document end",
+	yaml_ALIAS_EVENT:          "alias",
+	yaml_SCALAR_EVENT:         "scalar",
+	yaml_SEQUENCE_START_EVENT: "sequence start",
+	yaml_SEQUENCE_END_EVENT:   "sequence end",
+	yaml_MAPPING_START_EVENT:  "mapping start",
+	yaml_MAPPING_END_EVENT:    "mapping end",
+}
+
+func (e yaml_event_type_t) String() string {
+	if e < 0 || int(e) >= len(eventStrings) {
+		return fmt.Sprintf("unknown event %d", e)
+	}
+	return eventStrings[e]
+}
+
+// The event structure.
+type yaml_event_t struct {
+
+	// The event type.
+	typ yaml_event_type_t
+
+	// The start and end of the event.
+	start_mark, end_mark yaml_mark_t
+
+	// The document encoding (for yaml_STREAM_START_EVENT).
+	encoding yaml_encoding_t
+
+	// The version directive (for yaml_DOCUMENT_START_EVENT).
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives (for yaml_DOCUMENT_START_EVENT).
+	tag_directives []yaml_tag_directive_t
+
+	// The anchor (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_ALIAS_EVENT).
+	anchor []byte
+
+	// The tag (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	tag []byte
+
+	// The scalar value (for yaml_SCALAR_EVENT).
+	value []byte
+
+	// Is the document start/end indicator implicit, or the tag optional?
+	// (for yaml_DOCUMENT_START_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_SCALAR_EVENT).
+	implicit bool
+
+	// Is the tag optional for any non-plain style? (for yaml_SCALAR_EVENT).
+	quoted_implicit bool
+
+	// The style (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	style yaml_style_t
+}
+
+func (e *yaml_event_t) scalar_style() yaml_scalar_style_t     { return yaml_scalar_style_t(e.style) }
+func (e *yaml_event_t) sequence_style() yaml_sequence_style_t { return yaml_sequence_style_t(e.style) }
+func (e *yaml_event_t) mapping_style() yaml_mapping_style_t   { return yaml_mapping_style_t(e.style) }
+
+// Nodes
+
+const (
+	yaml_NULL_TAG      = "tag:yaml.org,2002:null"      // The tag !!null with the only possible value: null.
+	yaml_BOOL_TAG      = "tag:yaml.org,2002:bool"      // The tag !!bool with the values: true and false.
+	yaml_STR_TAG       = "tag:yaml.org,2002:str"       // The tag !!str for string values.
+	yaml_INT_TAG       = "tag:yaml.org,2002:int"       // The tag !!int for integer values.
+	yaml_FLOAT_TAG     = "tag:yaml.org,2002:float"     // The tag !!float for float values.
+	yaml_TIMESTAMP_TAG = "tag:yaml.org,2002:timestamp" // The tag !!timestamp for date and time values.
+
+	yaml_SEQ_TAG = "tag:yaml.org,2002:seq" // The tag !!seq is used to denote sequences.
+	yaml_MAP_TAG = "tag:yaml.org,2002:map" // The tag !!map is used to denote mapping.
+
+	// Not in original libyaml.
+	yaml_BINARY_TAG = "tag:yaml.org,2002:binary"
+	yaml_MERGE_TAG  = "tag:yaml.org,2002:merge"
+
+	yaml_DEFAULT_SCALAR_TAG   = yaml_STR_TAG // The default scalar tag is !!str.
+	yaml_DEFAULT_SEQUENCE_TAG = yaml_SEQ_TAG // The default sequence tag is !!seq.
+	yaml_DEFAULT_MAPPING_TAG  = yaml_MAP_TAG // The default mapping tag is !!map.
+)
+
+type yaml_node_type_t int
+
+// Node types.
+const (
+	// An empty node.
+	yaml_NO_NODE yaml_node_type_t = iota
+
+	yaml_SCALAR_NODE   // A scalar node.
+	yaml_SEQUENCE_NODE // A sequence node.
+	yaml_MAPPING_NODE  // A mapping node.
+)
+
+// An element of a sequence node.
+type yaml_node_item_t int
+
+// An element of a mapping node.
+type yaml_node_pair_t struct {
+	key   int // The key of the element.
+	value int // The value of the element.
+}
+
+// The node structure.
+type yaml_node_t struct {
+	typ yaml_node_type_t // The node type.
+	tag []byte           // The node tag.
+
+	// The node data.
+
+	// The scalar parameters (for yaml_SCALAR_NODE).
+	scalar struct {
+		value  []byte              // The scalar value.
+		length int                 // The length of the scalar value.
+		style  yaml_scalar_style_t // The scalar style.
+	}
+
+	// The sequence parameters (for YAML_SEQUENCE_NODE).
+	sequence struct {
+		items_data []yaml_node_item_t    // The stack of sequence items.
+		style      yaml_sequence_style_t // The sequence style.
+	}
+
+	// The mapping parameters (for yaml_MAPPING_NODE).
+	mapping struct {
+		pairs_data  []yaml_node_pair_t   // The stack of mapping pairs (key, value).
+		pairs_start *yaml_node_pair_t    // The beginning of the stack.
+		pairs_end   *yaml_node_pair_t    // The end of the stack.
+		pairs_top   *yaml_node_pair_t    // The top of the stack.
+		style       yaml_mapping_style_t // The mapping style.
+	}
+
+	start_mark yaml_mark_t // The beginning of the node.
+	end_mark   yaml_mark_t // The end of the node.
+
+}
+
+// The document structure.
+type yaml_document_t struct {
+
+	// The document nodes.
+	nodes []yaml_node_t
+
+	// The version directive.
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives.
+	tag_directives_data  []yaml_tag_directive_t
+	tag_directives_start int // The beginning of the tag directives list.
+	tag_directives_end   int // The end of the tag directives list.
+
+	start_implicit int // Is the document start indicator implicit?
+	end_implicit   int // Is the document end indicator implicit?
+
+	// The start/end of the document.
+	start_mark, end_mark yaml_mark_t
+}
+
+// The prototype of a read handler.
+//
+// The read handler is called when the parser needs to read more bytes from the
+// source. The handler should write not more than size bytes to the buffer.
+// The number of written bytes should be set to the size_read variable.
+//
+// [in,out]   data        A pointer to an application data specified by
+//                        yaml_parser_set_input().
+// [out]      buffer      The buffer to write the data from the source.
+// [in]       size        The size of the buffer.
+// [out]      size_read   The actual number of bytes read from the source.
+//
+// On success, the handler should return 1.  If the handler failed,
+// the returned value should be 0. On EOF, the handler should set the
+// size_read to 0 and return 1.
+type yaml_read_handler_t func(parser *yaml_parser_t, buffer []byte) (n int, err error)
+
+// This structure holds information about a potential simple key.
+type yaml_simple_key_t struct {
+	possible     bool        // Is a simple key possible?
+	required     bool        // Is a simple key required?
+	token_number int         // The number of the token.
+	mark         yaml_mark_t // The position mark.
+}
+
+// The states of the parser.
+type yaml_parser_state_t int
+
+const (
+	yaml_PARSE_STREAM_START_STATE yaml_parser_state_t = iota
+
+	yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE           // Expect the beginning of an implicit document.
+	yaml_PARSE_DOCUMENT_START_STATE                    // Expect DOCUMENT-START.
+	yaml_PARSE_DOCUMENT_CONTENT_STATE                  // Expect the content of a document.
+	yaml_PARSE_DOCUMENT_END_STATE                      // Expect DOCUMENT-END.
+	yaml_PARSE_BLOCK_NODE_STATE                        // Expect a block node.
+	yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE // Expect a block node or indentless sequence.
+	yaml_PARSE_FLOW_NODE_STATE                         // Expect a flow node.
+	yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE        // Expect the first entry of a block sequence.
+	yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE              // Expect an entry of a block sequence.
+	yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE         // Expect an entry of an indentless sequence.
+	yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE           // Expect the first key of a block mapping.
+	yaml_PARSE_BLOCK_MAPPING_KEY_STATE                 // Expect a block mapping key.
+	yaml_PARSE_BLOCK_MAPPING_VALUE_STATE               // Expect a block mapping value.
+	yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE         // Expect the first entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE               // Expect an entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE   // Expect a key of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE // Expect a value of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE   // Expect the and of an ordered mapping entry.
+	yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE            // Expect the first key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_KEY_STATE                  // Expect a key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_VALUE_STATE                // Expect a value of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE          // Expect an empty value of a flow mapping.
+	yaml_PARSE_END_STATE                               // Expect nothing.
+)
+
+func (ps yaml_parser_state_t) String() string {
+	switch ps {
+	case yaml_PARSE_STREAM_START_STATE:
+		return "yaml_PARSE_STREAM_START_STATE"
+	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
+		return "yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_START_STATE:
+		return "yaml_PARSE_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
+		return "yaml_PARSE_DOCUMENT_CONTENT_STATE"
+	case yaml_PARSE_DOCUMENT_END_STATE:
+		return "yaml_PARSE_DOCUMENT_END_STATE"
+	case yaml_PARSE_BLOCK_NODE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_STATE"
+	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE"
+	case yaml_PARSE_FLOW_NODE_STATE:
+		return "yaml_PARSE_FLOW_NODE_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE"
+	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE"
+	case yaml_PARSE_END_STATE:
+		return "yaml_PARSE_END_STATE"
+	}
+	return "<unknown parser state>"
+}
+
+// This structure holds aliases data.
+type yaml_alias_data_t struct {
+	anchor []byte      // The anchor.
+	index  int         // The node id.
+	mark   yaml_mark_t // The anchor mark.
+}
+
+// The parser structure.
+//
+// All members are internal. Manage the structure using the
+// yaml_parser_ family of functions.
+type yaml_parser_t struct {
+
+	// Error handling
+
+	error yaml_error_type_t // Error type.
+
+	problem string // Error description.
+
+	// The byte about which the problem occurred.
+	problem_offset int
+	problem_value  int
+	problem_mark   yaml_mark_t
+
+	// The error context.
+	context      string
+	context_mark yaml_mark_t
+
+	// Reader stuff
+
+	read_handler yaml_read_handler_t // Read handler.
+
+	input_reader io.Reader // File input data.
+	input        []byte    // String input data.
+	input_pos    int
+
+	eof bool // EOF flag
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	unread int // The number of unread characters in the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The input encoding.
+
+	offset int         // The offset of the current position (in bytes).
+	mark   yaml_mark_t // The mark of the current position.
+
+	// Scanner stuff
+
+	stream_start_produced bool // Have we started to scan the input stream?
+	stream_end_produced   bool // Have we reached the end of the input stream?
+
+	flow_level int // The number of unclosed '[' and '{' indicators.
+
+	tokens          []yaml_token_t // The tokens queue.
+	tokens_head     int            // The head of the tokens queue.
+	tokens_parsed   int            // The number of tokens fetched from the queue.
+	token_available bool           // Does the tokens queue contain a token ready for dequeueing.
+
+	indent  int   // The current indentation level.
+	indents []int // The indentation levels stack.
+
+	simple_key_allowed bool                // May a simple key occur at the current position?
+	simple_keys        []yaml_simple_key_t // The stack of simple keys.
+	simple_keys_by_tok map[int]int         // possible simple_key indexes indexed by token_number
+
+	// Parser stuff
+
+	state          yaml_parser_state_t    // The current parser state.
+	states         []yaml_parser_state_t  // The parser states stack.
+	marks          []yaml_mark_t          // The stack of marks.
+	tag_directives []yaml_tag_directive_t // The list of TAG directives.
+
+	// Dumper stuff
+
+	aliases []yaml_alias_data_t // The alias data.
+
+	document *yaml_document_t // The currently parsed document.
+}
+
+// Emitter Definitions
+
+// The prototype of a write handler.
+//
+// The write handler is called when the emitter needs to flush the accumulated
+// characters to the output.  The handler should write @a size bytes of the
+// @a buffer to the output.
+//
+// @param[in,out]   data        A pointer to an application data specified by
+//                              yaml_emitter_set_output().
+// @param[in]       buffer      The buffer with bytes to be written.
+// @param[in]       size        The size of the buffer.
+//
+// @returns On success, the handler should return @c 1.  If the handler failed,
+// the returned value should be @c 0.
+//
+type yaml_write_handler_t func(emitter *yaml_emitter_t, buffer []byte) error
+
+type yaml_emitter_state_t int
+
+// The emitter states.
+const (
+	// Expect STREAM-START.
+	yaml_EMIT_STREAM_START_STATE yaml_emitter_state_t = iota
+
+	yaml_EMIT_FIRST_DOCUMENT_START_STATE       // Expect the first DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_START_STATE             // Expect DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_CONTENT_STATE           // Expect the content of a document.
+	yaml_EMIT_DOCUMENT_END_STATE               // Expect DOCUMENT-END.
+	yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE   // Expect the first item of a flow sequence.
+	yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE         // Expect an item of a flow sequence.
+	yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE     // Expect the first key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_KEY_STATE           // Expect a key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE  // Expect a value for a simple key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_VALUE_STATE         // Expect a value of a flow mapping.
+	yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE  // Expect the first item of a block sequence.
+	yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE        // Expect an item of a block sequence.
+	yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE    // Expect the first key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_KEY_STATE          // Expect the key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE // Expect a value for a simple key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_VALUE_STATE        // Expect a value of a block mapping.
+	yaml_EMIT_END_STATE                        // Expect nothing.
+)
+
+// The emitter structure.
+//
+// All members are internal.  Manage the structure using the @c yaml_emitter_
+// family of functions.
+type yaml_emitter_t struct {
+
+	// Error handling
+
+	error   yaml_error_type_t // Error type.
+	problem string            // Error description.
+
+	// Writer stuff
+
+	write_handler yaml_write_handler_t // Write handler.
+
+	output_buffer *[]byte   // String output data.
+	output_writer io.Writer // File output data.
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The stream encoding.
+
+	// Emitter stuff
+
+	canonical   bool         // If the output is in the canonical style?
+	best_indent int          // The number of indentation spaces.
+	best_width  int          // The preferred width of the output lines.
+	unicode     bool         // Allow unescaped non-ASCII characters?
+	line_break  yaml_break_t // The preferred line break.
+
+	state  yaml_emitter_state_t   // The current emitter state.
+	states []yaml_emitter_state_t // The stack of states.
+
+	events      []yaml_event_t // The event queue.
+	events_head int            // The head of the event queue.
+
+	indents []int // The stack of indentation levels.
+
+	tag_directives []yaml_tag_directive_t // The list of tag directives.
+
+	indent int // The current indentation level.
+
+	flow_level int // The current flow level.
+
+	root_context       bool // Is it the document root context?
+	sequence_context   bool // Is it a sequence context?
+	mapping_context    bool // Is it a mapping context?
+	simple_key_context bool // Is it a simple mapping key context?
+
+	line       int  // The current line.
+	column     int  // The current column.
+	whitespace bool // If the last character was a whitespace?
+	indention  bool // If the last character was an indentation character (' ', '-', '?', ':')?
+	open_ended bool // If an explicit document end is required?
+
+	// Anchor analysis.
+	anchor_data struct {
+		anchor []byte // The anchor value.
+		alias  bool   // Is it an alias?
+	}
+
+	// Tag analysis.
+	tag_data struct {
+		handle []byte // The tag handle.
+		suffix []byte // The tag suffix.
+	}
+
+	// Scalar analysis.
+	scalar_data struct {
+		value                 []byte              // The scalar value.
+		multiline             bool                // Does the scalar contain line breaks?
+		flow_plain_allowed    bool                // Can the scalar be expessed in the flow plain style?
+		block_plain_allowed   bool                // Can the scalar be expressed in the block plain style?
+		single_quoted_allowed bool                // Can the scalar be expressed in the single quoted style?
+		block_allowed         bool                // Can the scalar be expressed in the literal or folded styles?
+		style                 yaml_scalar_style_t // The output style.
+	}
+
+	// Dumper stuff
+
+	opened bool // If the stream was already opened?
+	closed bool // If the stream was already closed?
+
+	// The information associated with the document nodes.
+	anchors *struct {
+		references int  // The number of references.
+		anchor     int  // The anchor id.
+		serialized bool // If the node has been emitted?
+	}
+
+	last_anchor_id int // The last assigned anchor id.
+
+	document *yaml_document_t // The currently emitted document.
+}

vendor/gopkg.in/yaml.v2/yamlprivateh.go

@@ -0,0 +1,173 @@
+package yaml
+
+const (
+	// The size of the input raw buffer.
+	input_raw_buffer_size = 512
+
+	// The size of the input buffer.
+	// It should be possible to decode the whole raw buffer.
+	input_buffer_size = input_raw_buffer_size * 3
+
+	// The size of the output buffer.
+	output_buffer_size = 128
+
+	// The size of the output raw buffer.
+	// It should be possible to encode the whole output buffer.
+	output_raw_buffer_size = (output_buffer_size*2 + 2)
+
+	// The size of other stacks and queues.
+	initial_stack_size  = 16
+	initial_queue_size  = 16
+	initial_string_size = 16
+)
+
+// Check if the character at the specified position is an alphabetical
+// character, a digit, '_', or '-'.
+func is_alpha(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'Z' || b[i] >= 'a' && b[i] <= 'z' || b[i] == '_' || b[i] == '-'
+}
+
+// Check if the character at the specified position is a digit.
+func is_digit(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9'
+}
+
+// Get the value of a digit.
+func as_digit(b []byte, i int) int {
+	return int(b[i]) - '0'
+}
+
+// Check if the character at the specified position is a hex-digit.
+func is_hex(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'F' || b[i] >= 'a' && b[i] <= 'f'
+}
+
+// Get the value of a hex-digit.
+func as_hex(b []byte, i int) int {
+	bi := b[i]
+	if bi >= 'A' && bi <= 'F' {
+		return int(bi) - 'A' + 10
+	}
+	if bi >= 'a' && bi <= 'f' {
+		return int(bi) - 'a' + 10
+	}
+	return int(bi) - '0'
+}
+
+// Check if the character is ASCII.
+func is_ascii(b []byte, i int) bool {
+	return b[i] <= 0x7F
+}
+
+// Check if the character at the start of the buffer can be printed unescaped.
+func is_printable(b []byte, i int) bool {
+	return ((b[i] == 0x0A) || // . == #x0A
+		(b[i] >= 0x20 && b[i] <= 0x7E) || // #x20 <= . <= #x7E
+		(b[i] == 0xC2 && b[i+1] >= 0xA0) || // #0xA0 <= . <= #xD7FF
+		(b[i] > 0xC2 && b[i] < 0xED) ||
+		(b[i] == 0xED && b[i+1] < 0xA0) ||
+		(b[i] == 0xEE) ||
+		(b[i] == 0xEF && // #xE000 <= . <= #xFFFD
+			!(b[i+1] == 0xBB && b[i+2] == 0xBF) && // && . != #xFEFF
+			!(b[i+1] == 0xBF && (b[i+2] == 0xBE || b[i+2] == 0xBF))))
+}
+
+// Check if the character at the specified position is NUL.
+func is_z(b []byte, i int) bool {
+	return b[i] == 0x00
+}
+
+// Check if the beginning of the buffer is a BOM.
+func is_bom(b []byte, i int) bool {
+	return b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF
+}
+
+// Check if the character at the specified position is space.
+func is_space(b []byte, i int) bool {
+	return b[i] == ' '
+}
+
+// Check if the character at the specified position is tab.
+func is_tab(b []byte, i int) bool {
+	return b[i] == '\t'
+}
+
+// Check if the character at the specified position is blank (space or tab).
+func is_blank(b []byte, i int) bool {
+	//return is_space(b, i) || is_tab(b, i)
+	return b[i] == ' ' || b[i] == '\t'
+}
+
+// Check if the character at the specified position is a line break.
+func is_break(b []byte, i int) bool {
+	return (b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9) // PS (#x2029)
+}
+
+func is_crlf(b []byte, i int) bool {
+	return b[i] == '\r' && b[i+1] == '\n'
+}
+
+// Check if the character is a line break or NUL.
+func is_breakz(b []byte, i int) bool {
+	//return is_break(b, i) || is_z(b, i)
+	return (        // is_break:
+	b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		// is_z:
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, or NUL.
+func is_spacez(b []byte, i int) bool {
+	//return is_space(b, i) || is_breakz(b, i)
+	return ( // is_space:
+	b[i] == ' ' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, tab, or NUL.
+func is_blankz(b []byte, i int) bool {
+	//return is_blank(b, i) || is_breakz(b, i)
+	return ( // is_blank:
+	b[i] == ' ' || b[i] == '\t' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Determine the width of the character.
+func width(b byte) int {
+	// Don't replace these by a switch without first
+	// confirming that it is being inlined.
+	if b&0x80 == 0x00 {
+		return 1
+	}
+	if b&0xE0 == 0xC0 {
+		return 2
+	}
+	if b&0xF0 == 0xE0 {
+		return 3
+	}
+	if b&0xF8 == 0xF0 {
+		return 4
+	}
+	return 0
+
+}

vendor/gopkg.in/yaml.v3/LICENSE

@@ -0,0 +1,50 @@
+
+This project is covered by two different licenses: MIT and Apache.
+
+#### MIT License ####
+
+The following files were ported to Go from C files of libyaml, and thus
+are still covered by their original MIT license, with the additional
+copyright staring in 2011 when the project was ported over:
+
+    apic.go emitterc.go parserc.go readerc.go scannerc.go
+    writerc.go yamlh.go yamlprivateh.go
+
+Copyright (c) 2006-2010 Kirill Simonov
+Copyright (c) 2006-2011 Kirill Simonov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+### Apache License ###
+
+All the remaining project files are covered by the Apache license:
+
+Copyright (c) 2011-2019 Canonical Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/gopkg.in/yaml.v3/NOTICE

@@ -0,0 +1,13 @@
+Copyright 2011-2016 Canonical Ltd.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/gopkg.in/yaml.v3/README.md

@@ -0,0 +1,150 @@
+# YAML support for the Go language
+
+Introduction
+------------
+
+The yaml package enables Go programs to comfortably encode and decode YAML
+values. It was developed within [Canonical](https://www.canonical.com) as
+part of the [juju](https://juju.ubuntu.com) project, and is based on a
+pure Go port of the well-known [libyaml](http://pyyaml.org/wiki/LibYAML)
+C library to parse and generate YAML data quickly and reliably.
+
+Compatibility
+-------------
+
+The yaml package supports most of YAML 1.2, but preserves some behavior
+from 1.1 for backwards compatibility.
+
+Specifically, as of v3 of the yaml package:
+
+ - YAML 1.1 bools (_yes/no, on/off_) are supported as long as they are being
+   decoded into a typed bool value. Otherwise they behave as a string. Booleans
+   in YAML 1.2 are _true/false_ only.
+ - Octals encode and decode as _0777_ per YAML 1.1, rather than _0o777_
+   as specified in YAML 1.2, because most parsers still use the old format.
+   Octals in the  _0o777_ format are supported though, so new files work.
+ - Does not support base-60 floats. These are gone from YAML 1.2, and were
+   actually never supported by this package as it's clearly a poor choice.
+
+and offers backwards
+compatibility with YAML 1.1 in some cases.
+1.2, including support for
+anchors, tags, map merging, etc. Multi-document unmarshalling is not yet
+implemented, and base-60 floats from YAML 1.1 are purposefully not
+supported since they're a poor design and are gone in YAML 1.2.
+
+Installation and usage
+----------------------
+
+The import path for the package is *gopkg.in/yaml.v3*.
+
+To install it, run:
+
+    go get gopkg.in/yaml.v3
+
+API documentation
+-----------------
+
+If opened in a browser, the import path itself leads to the API documentation:
+
+  - [https://gopkg.in/yaml.v3](https://gopkg.in/yaml.v3)
+
+API stability
+-------------
+
+The package API for yaml v3 will remain stable as described in [gopkg.in](https://gopkg.in).
+
+
+License
+-------
+
+The yaml package is licensed under the MIT and Apache License 2.0 licenses.
+Please see the LICENSE file for details.
+
+
+Example
+-------
+
+```Go
+package main
+
+import (
+        "fmt"
+        "log"
+
+        "gopkg.in/yaml.v3"
+)
+
+var data = `
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+`
+
+// Note: struct fields must be public in order for unmarshal to
+// correctly populate the data.
+type T struct {
+        A string
+        B struct {
+                RenamedC int   `yaml:"c"`
+                D        []int `yaml:",flow"`
+        }
+}
+
+func main() {
+        t := T{}
+    
+        err := yaml.Unmarshal([]byte(data), &t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t:\n%v\n\n", t)
+    
+        d, err := yaml.Marshal(&t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t dump:\n%s\n\n", string(d))
+    
+        m := make(map[interface{}]interface{})
+    
+        err = yaml.Unmarshal([]byte(data), &m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m:\n%v\n\n", m)
+    
+        d, err = yaml.Marshal(&m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m dump:\n%s\n\n", string(d))
+}
+```
+
+This example will generate the following output:
+
+```
+--- t:
+{Easy! {2 [3 4]}}
+
+--- t dump:
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+
+
+--- m:
+map[a:Easy! b:map[c:2 d:[3 4]]]
+
+--- m dump:
+a: Easy!
+b:
+  c: 2
+  d:
+  - 3
+  - 4
+```
+

vendor/gopkg.in/yaml.v3/apic.go

@@ -0,0 +1,747 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"io"
+)
+
+func yaml_insert_token(parser *yaml_parser_t, pos int, token *yaml_token_t) {
+	//fmt.Println("yaml_insert_token", "pos:", pos, "typ:", token.typ, "head:", parser.tokens_head, "len:", len(parser.tokens))
+
+	// Check if we can move the queue at the beginning of the buffer.
+	if parser.tokens_head > 0 && len(parser.tokens) == cap(parser.tokens) {
+		if parser.tokens_head != len(parser.tokens) {
+			copy(parser.tokens, parser.tokens[parser.tokens_head:])
+		}
+		parser.tokens = parser.tokens[:len(parser.tokens)-parser.tokens_head]
+		parser.tokens_head = 0
+	}
+	parser.tokens = append(parser.tokens, *token)
+	if pos < 0 {
+		return
+	}
+	copy(parser.tokens[parser.tokens_head+pos+1:], parser.tokens[parser.tokens_head+pos:])
+	parser.tokens[parser.tokens_head+pos] = *token
+}
+
+// Create a new parser object.
+func yaml_parser_initialize(parser *yaml_parser_t) bool {
+	*parser = yaml_parser_t{
+		raw_buffer: make([]byte, 0, input_raw_buffer_size),
+		buffer:     make([]byte, 0, input_buffer_size),
+	}
+	return true
+}
+
+// Destroy a parser object.
+func yaml_parser_delete(parser *yaml_parser_t) {
+	*parser = yaml_parser_t{}
+}
+
+// String read handler.
+func yaml_string_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	if parser.input_pos == len(parser.input) {
+		return 0, io.EOF
+	}
+	n = copy(buffer, parser.input[parser.input_pos:])
+	parser.input_pos += n
+	return n, nil
+}
+
+// Reader read handler.
+func yaml_reader_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	return parser.input_reader.Read(buffer)
+}
+
+// Set a string input.
+func yaml_parser_set_input_string(parser *yaml_parser_t, input []byte) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_string_read_handler
+	parser.input = input
+	parser.input_pos = 0
+}
+
+// Set a file input.
+func yaml_parser_set_input_reader(parser *yaml_parser_t, r io.Reader) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_reader_read_handler
+	parser.input_reader = r
+}
+
+// Set the source encoding.
+func yaml_parser_set_encoding(parser *yaml_parser_t, encoding yaml_encoding_t) {
+	if parser.encoding != yaml_ANY_ENCODING {
+		panic("must set the encoding only once")
+	}
+	parser.encoding = encoding
+}
+
+// Create a new emitter object.
+func yaml_emitter_initialize(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{
+		buffer:     make([]byte, output_buffer_size),
+		raw_buffer: make([]byte, 0, output_raw_buffer_size),
+		states:     make([]yaml_emitter_state_t, 0, initial_stack_size),
+		events:     make([]yaml_event_t, 0, initial_queue_size),
+		best_width: -1,
+	}
+}
+
+// Destroy an emitter object.
+func yaml_emitter_delete(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{}
+}
+
+// String write handler.
+func yaml_string_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	*emitter.output_buffer = append(*emitter.output_buffer, buffer...)
+	return nil
+}
+
+// yaml_writer_write_handler uses emitter.output_writer to write the
+// emitted text.
+func yaml_writer_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	_, err := emitter.output_writer.Write(buffer)
+	return err
+}
+
+// Set a string output.
+func yaml_emitter_set_output_string(emitter *yaml_emitter_t, output_buffer *[]byte) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_string_write_handler
+	emitter.output_buffer = output_buffer
+}
+
+// Set a file output.
+func yaml_emitter_set_output_writer(emitter *yaml_emitter_t, w io.Writer) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_writer_write_handler
+	emitter.output_writer = w
+}
+
+// Set the output encoding.
+func yaml_emitter_set_encoding(emitter *yaml_emitter_t, encoding yaml_encoding_t) {
+	if emitter.encoding != yaml_ANY_ENCODING {
+		panic("must set the output encoding only once")
+	}
+	emitter.encoding = encoding
+}
+
+// Set the canonical output style.
+func yaml_emitter_set_canonical(emitter *yaml_emitter_t, canonical bool) {
+	emitter.canonical = canonical
+}
+
+// Set the indentation increment.
+func yaml_emitter_set_indent(emitter *yaml_emitter_t, indent int) {
+	if indent < 2 || indent > 9 {
+		indent = 2
+	}
+	emitter.best_indent = indent
+}
+
+// Set the preferred line width.
+func yaml_emitter_set_width(emitter *yaml_emitter_t, width int) {
+	if width < 0 {
+		width = -1
+	}
+	emitter.best_width = width
+}
+
+// Set if unescaped non-ASCII characters are allowed.
+func yaml_emitter_set_unicode(emitter *yaml_emitter_t, unicode bool) {
+	emitter.unicode = unicode
+}
+
+// Set the preferred line break character.
+func yaml_emitter_set_break(emitter *yaml_emitter_t, line_break yaml_break_t) {
+	emitter.line_break = line_break
+}
+
+///*
+// * Destroy a token object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_token_delete(yaml_token_t *token)
+//{
+//    assert(token);  // Non-NULL token object expected.
+//
+//    switch (token.type)
+//    {
+//        case YAML_TAG_DIRECTIVE_TOKEN:
+//            yaml_free(token.data.tag_directive.handle);
+//            yaml_free(token.data.tag_directive.prefix);
+//            break;
+//
+//        case YAML_ALIAS_TOKEN:
+//            yaml_free(token.data.alias.value);
+//            break;
+//
+//        case YAML_ANCHOR_TOKEN:
+//            yaml_free(token.data.anchor.value);
+//            break;
+//
+//        case YAML_TAG_TOKEN:
+//            yaml_free(token.data.tag.handle);
+//            yaml_free(token.data.tag.suffix);
+//            break;
+//
+//        case YAML_SCALAR_TOKEN:
+//            yaml_free(token.data.scalar.value);
+//            break;
+//
+//        default:
+//            break;
+//    }
+//
+//    memset(token, 0, sizeof(yaml_token_t));
+//}
+//
+///*
+// * Check if a string is a valid UTF-8 sequence.
+// *
+// * Check 'reader.c' for more details on UTF-8 encoding.
+// */
+//
+//static int
+//yaml_check_utf8(yaml_char_t *start, size_t length)
+//{
+//    yaml_char_t *end = start+length;
+//    yaml_char_t *pointer = start;
+//
+//    while (pointer < end) {
+//        unsigned char octet;
+//        unsigned int width;
+//        unsigned int value;
+//        size_t k;
+//
+//        octet = pointer[0];
+//        width = (octet & 0x80) == 0x00 ? 1 :
+//                (octet & 0xE0) == 0xC0 ? 2 :
+//                (octet & 0xF0) == 0xE0 ? 3 :
+//                (octet & 0xF8) == 0xF0 ? 4 : 0;
+//        value = (octet & 0x80) == 0x00 ? octet & 0x7F :
+//                (octet & 0xE0) == 0xC0 ? octet & 0x1F :
+//                (octet & 0xF0) == 0xE0 ? octet & 0x0F :
+//                (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
+//        if (!width) return 0;
+//        if (pointer+width > end) return 0;
+//        for (k = 1; k < width; k ++) {
+//            octet = pointer[k];
+//            if ((octet & 0xC0) != 0x80) return 0;
+//            value = (value << 6) + (octet & 0x3F);
+//        }
+//        if (!((width == 1) ||
+//            (width == 2 && value >= 0x80) ||
+//            (width == 3 && value >= 0x800) ||
+//            (width == 4 && value >= 0x10000))) return 0;
+//
+//        pointer += width;
+//    }
+//
+//    return 1;
+//}
+//
+
+// Create STREAM-START.
+func yaml_stream_start_event_initialize(event *yaml_event_t, encoding yaml_encoding_t) {
+	*event = yaml_event_t{
+		typ:      yaml_STREAM_START_EVENT,
+		encoding: encoding,
+	}
+}
+
+// Create STREAM-END.
+func yaml_stream_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_STREAM_END_EVENT,
+	}
+}
+
+// Create DOCUMENT-START.
+func yaml_document_start_event_initialize(
+	event *yaml_event_t,
+	version_directive *yaml_version_directive_t,
+	tag_directives []yaml_tag_directive_t,
+	implicit bool,
+) {
+	*event = yaml_event_t{
+		typ:               yaml_DOCUMENT_START_EVENT,
+		version_directive: version_directive,
+		tag_directives:    tag_directives,
+		implicit:          implicit,
+	}
+}
+
+// Create DOCUMENT-END.
+func yaml_document_end_event_initialize(event *yaml_event_t, implicit bool) {
+	*event = yaml_event_t{
+		typ:      yaml_DOCUMENT_END_EVENT,
+		implicit: implicit,
+	}
+}
+
+// Create ALIAS.
+func yaml_alias_event_initialize(event *yaml_event_t, anchor []byte) bool {
+	*event = yaml_event_t{
+		typ:    yaml_ALIAS_EVENT,
+		anchor: anchor,
+	}
+	return true
+}
+
+// Create SCALAR.
+func yaml_scalar_event_initialize(event *yaml_event_t, anchor, tag, value []byte, plain_implicit, quoted_implicit bool, style yaml_scalar_style_t) bool {
+	*event = yaml_event_t{
+		typ:             yaml_SCALAR_EVENT,
+		anchor:          anchor,
+		tag:             tag,
+		value:           value,
+		implicit:        plain_implicit,
+		quoted_implicit: quoted_implicit,
+		style:           yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-START.
+func yaml_sequence_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_sequence_style_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_SEQUENCE_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-END.
+func yaml_sequence_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_SEQUENCE_END_EVENT,
+	}
+	return true
+}
+
+// Create MAPPING-START.
+func yaml_mapping_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_mapping_style_t) {
+	*event = yaml_event_t{
+		typ:      yaml_MAPPING_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+}
+
+// Create MAPPING-END.
+func yaml_mapping_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_MAPPING_END_EVENT,
+	}
+}
+
+// Destroy an event object.
+func yaml_event_delete(event *yaml_event_t) {
+	*event = yaml_event_t{}
+}
+
+///*
+// * Create a document object.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_initialize(document *yaml_document_t,
+//        version_directive *yaml_version_directive_t,
+//        tag_directives_start *yaml_tag_directive_t,
+//        tag_directives_end *yaml_tag_directive_t,
+//        start_implicit int, end_implicit int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    struct {
+//        start *yaml_node_t
+//        end *yaml_node_t
+//        top *yaml_node_t
+//    } nodes = { NULL, NULL, NULL }
+//    version_directive_copy *yaml_version_directive_t = NULL
+//    struct {
+//        start *yaml_tag_directive_t
+//        end *yaml_tag_directive_t
+//        top *yaml_tag_directive_t
+//    } tag_directives_copy = { NULL, NULL, NULL }
+//    value yaml_tag_directive_t = { NULL, NULL }
+//    mark yaml_mark_t = { 0, 0, 0 }
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert((tag_directives_start && tag_directives_end) ||
+//            (tag_directives_start == tag_directives_end))
+//                            // Valid tag directives are expected.
+//
+//    if (!STACK_INIT(&context, nodes, INITIAL_STACK_SIZE)) goto error
+//
+//    if (version_directive) {
+//        version_directive_copy = yaml_malloc(sizeof(yaml_version_directive_t))
+//        if (!version_directive_copy) goto error
+//        version_directive_copy.major = version_directive.major
+//        version_directive_copy.minor = version_directive.minor
+//    }
+//
+//    if (tag_directives_start != tag_directives_end) {
+//        tag_directive *yaml_tag_directive_t
+//        if (!STACK_INIT(&context, tag_directives_copy, INITIAL_STACK_SIZE))
+//            goto error
+//        for (tag_directive = tag_directives_start
+//                tag_directive != tag_directives_end; tag_directive ++) {
+//            assert(tag_directive.handle)
+//            assert(tag_directive.prefix)
+//            if (!yaml_check_utf8(tag_directive.handle,
+//                        strlen((char *)tag_directive.handle)))
+//                goto error
+//            if (!yaml_check_utf8(tag_directive.prefix,
+//                        strlen((char *)tag_directive.prefix)))
+//                goto error
+//            value.handle = yaml_strdup(tag_directive.handle)
+//            value.prefix = yaml_strdup(tag_directive.prefix)
+//            if (!value.handle || !value.prefix) goto error
+//            if (!PUSH(&context, tag_directives_copy, value))
+//                goto error
+//            value.handle = NULL
+//            value.prefix = NULL
+//        }
+//    }
+//
+//    DOCUMENT_INIT(*document, nodes.start, nodes.end, version_directive_copy,
+//            tag_directives_copy.start, tag_directives_copy.top,
+//            start_implicit, end_implicit, mark, mark)
+//
+//    return 1
+//
+//error:
+//    STACK_DEL(&context, nodes)
+//    yaml_free(version_directive_copy)
+//    while (!STACK_EMPTY(&context, tag_directives_copy)) {
+//        value yaml_tag_directive_t = POP(&context, tag_directives_copy)
+//        yaml_free(value.handle)
+//        yaml_free(value.prefix)
+//    }
+//    STACK_DEL(&context, tag_directives_copy)
+//    yaml_free(value.handle)
+//    yaml_free(value.prefix)
+//
+//    return 0
+//}
+//
+///*
+// * Destroy a document object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_document_delete(document *yaml_document_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    tag_directive *yaml_tag_directive_t
+//
+//    context.error = YAML_NO_ERROR // Eliminate a compiler warning.
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    while (!STACK_EMPTY(&context, document.nodes)) {
+//        node yaml_node_t = POP(&context, document.nodes)
+//        yaml_free(node.tag)
+//        switch (node.type) {
+//            case YAML_SCALAR_NODE:
+//                yaml_free(node.data.scalar.value)
+//                break
+//            case YAML_SEQUENCE_NODE:
+//                STACK_DEL(&context, node.data.sequence.items)
+//                break
+//            case YAML_MAPPING_NODE:
+//                STACK_DEL(&context, node.data.mapping.pairs)
+//                break
+//            default:
+//                assert(0) // Should not happen.
+//        }
+//    }
+//    STACK_DEL(&context, document.nodes)
+//
+//    yaml_free(document.version_directive)
+//    for (tag_directive = document.tag_directives.start
+//            tag_directive != document.tag_directives.end
+//            tag_directive++) {
+//        yaml_free(tag_directive.handle)
+//        yaml_free(tag_directive.prefix)
+//    }
+//    yaml_free(document.tag_directives.start)
+//
+//    memset(document, 0, sizeof(yaml_document_t))
+//}
+//
+///**
+// * Get a document node.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_node(document *yaml_document_t, index int)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (index > 0 && document.nodes.start + index <= document.nodes.top) {
+//        return document.nodes.start + index - 1
+//    }
+//    return NULL
+//}
+//
+///**
+// * Get the root object.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_root_node(document *yaml_document_t)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (document.nodes.top != document.nodes.start) {
+//        return document.nodes.start
+//    }
+//    return NULL
+//}
+//
+///*
+// * Add a scalar node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_scalar(document *yaml_document_t,
+//        tag *yaml_char_t, value *yaml_char_t, length int,
+//        style yaml_scalar_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    value_copy *yaml_char_t = NULL
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert(value) // Non-NULL value is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SCALAR_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (length < 0) {
+//        length = strlen((char *)value)
+//    }
+//
+//    if (!yaml_check_utf8(value, length)) goto error
+//    value_copy = yaml_malloc(length+1)
+//    if (!value_copy) goto error
+//    memcpy(value_copy, value, length)
+//    value_copy[length] = '\0'
+//
+//    SCALAR_NODE_INIT(node, tag_copy, value_copy, length, style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    yaml_free(tag_copy)
+//    yaml_free(value_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a sequence node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_sequence(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_sequence_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_item_t
+//        end *yaml_node_item_t
+//        top *yaml_node_item_t
+//    } items = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, items, INITIAL_STACK_SIZE)) goto error
+//
+//    SEQUENCE_NODE_INIT(node, tag_copy, items.start, items.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, items)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a mapping node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_mapping(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_mapping_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_pair_t
+//        end *yaml_node_pair_t
+//        top *yaml_node_pair_t
+//    } pairs = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_MAPPING_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, pairs, INITIAL_STACK_SIZE)) goto error
+//
+//    MAPPING_NODE_INIT(node, tag_copy, pairs.start, pairs.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, pairs)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Append an item to a sequence node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_sequence_item(document *yaml_document_t,
+//        sequence int, item int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(sequence > 0
+//            && document.nodes.start + sequence <= document.nodes.top)
+//                            // Valid sequence id is required.
+//    assert(document.nodes.start[sequence-1].type == YAML_SEQUENCE_NODE)
+//                            // A sequence node is required.
+//    assert(item > 0 && document.nodes.start + item <= document.nodes.top)
+//                            // Valid item id is required.
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[sequence-1].data.sequence.items, item))
+//        return 0
+//
+//    return 1
+//}
+//
+///*
+// * Append a pair of a key and a value to a mapping node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_mapping_pair(document *yaml_document_t,
+//        mapping int, key int, value int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    pair yaml_node_pair_t
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(mapping > 0
+//            && document.nodes.start + mapping <= document.nodes.top)
+//                            // Valid mapping id is required.
+//    assert(document.nodes.start[mapping-1].type == YAML_MAPPING_NODE)
+//                            // A mapping node is required.
+//    assert(key > 0 && document.nodes.start + key <= document.nodes.top)
+//                            // Valid key id is required.
+//    assert(value > 0 && document.nodes.start + value <= document.nodes.top)
+//                            // Valid value id is required.
+//
+//    pair.key = key
+//    pair.value = value
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[mapping-1].data.mapping.pairs, pair))
+//        return 0
+//
+//    return 1
+//}
+//
+//

vendor/gopkg.in/yaml.v3/encode.go

@@ -0,0 +1,577 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"encoding"
+	"fmt"
+	"io"
+	"reflect"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
+
+type encoder struct {
+	emitter  yaml_emitter_t
+	event    yaml_event_t
+	out      []byte
+	flow     bool
+	indent   int
+	doneInit bool
+}
+
+func newEncoder() *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_string(&e.emitter, &e.out)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func newEncoderWithWriter(w io.Writer) *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_writer(&e.emitter, w)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func (e *encoder) init() {
+	if e.doneInit {
+		return
+	}
+	if e.indent == 0 {
+		e.indent = 4
+	}
+	e.emitter.best_indent = e.indent
+	yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING)
+	e.emit()
+	e.doneInit = true
+}
+
+func (e *encoder) finish() {
+	e.emitter.open_ended = false
+	yaml_stream_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) destroy() {
+	yaml_emitter_delete(&e.emitter)
+}
+
+func (e *encoder) emit() {
+	// This will internally delete the e.event value.
+	e.must(yaml_emitter_emit(&e.emitter, &e.event))
+}
+
+func (e *encoder) must(ok bool) {
+	if !ok {
+		msg := e.emitter.problem
+		if msg == "" {
+			msg = "unknown problem generating YAML content"
+		}
+		failf("%s", msg)
+	}
+}
+
+func (e *encoder) marshalDoc(tag string, in reflect.Value) {
+	e.init()
+	var node *Node
+	if in.IsValid() {
+		node, _ = in.Interface().(*Node)
+	}
+	if node != nil && node.Kind == DocumentNode {
+		e.nodev(in)
+	} else {
+		yaml_document_start_event_initialize(&e.event, nil, nil, true)
+		e.emit()
+		e.marshal(tag, in)
+		yaml_document_end_event_initialize(&e.event, true)
+		e.emit()
+	}
+}
+
+func (e *encoder) marshal(tag string, in reflect.Value) {
+	tag = shortTag(tag)
+	if !in.IsValid() || in.Kind() == reflect.Ptr && in.IsNil() {
+		e.nilv()
+		return
+	}
+	iface := in.Interface()
+	switch value := iface.(type) {
+	case *Node:
+		e.nodev(in)
+		return
+	case Node:
+		if !in.CanAddr() {
+			var n = reflect.New(in.Type()).Elem()
+			n.Set(in)
+			in = n
+		}
+		e.nodev(in.Addr())
+		return
+	case time.Time:
+		e.timev(tag, in)
+		return
+	case *time.Time:
+		e.timev(tag, in.Elem())
+		return
+	case time.Duration:
+		e.stringv(tag, reflect.ValueOf(value.String()))
+		return
+	case Marshaler:
+		v, err := value.MarshalYAML()
+		if err != nil {
+			fail(err)
+		}
+		if v == nil {
+			e.nilv()
+			return
+		}
+		e.marshal(tag, reflect.ValueOf(v))
+		return
+	case encoding.TextMarshaler:
+		text, err := value.MarshalText()
+		if err != nil {
+			fail(err)
+		}
+		in = reflect.ValueOf(string(text))
+	case nil:
+		e.nilv()
+		return
+	}
+	switch in.Kind() {
+	case reflect.Interface:
+		e.marshal(tag, in.Elem())
+	case reflect.Map:
+		e.mapv(tag, in)
+	case reflect.Ptr:
+		e.marshal(tag, in.Elem())
+	case reflect.Struct:
+		e.structv(tag, in)
+	case reflect.Slice, reflect.Array:
+		e.slicev(tag, in)
+	case reflect.String:
+		e.stringv(tag, in)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		e.intv(tag, in)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		e.uintv(tag, in)
+	case reflect.Float32, reflect.Float64:
+		e.floatv(tag, in)
+	case reflect.Bool:
+		e.boolv(tag, in)
+	default:
+		panic("cannot marshal type: " + in.Type().String())
+	}
+}
+
+func (e *encoder) mapv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		keys := keyList(in.MapKeys())
+		sort.Sort(keys)
+		for _, k := range keys {
+			e.marshal("", k)
+			e.marshal("", in.MapIndex(k))
+		}
+	})
+}
+
+func (e *encoder) fieldByIndex(v reflect.Value, index []int) (field reflect.Value) {
+	for _, num := range index {
+		for {
+			if v.Kind() == reflect.Ptr {
+				if v.IsNil() {
+					return reflect.Value{}
+				}
+				v = v.Elem()
+				continue
+			}
+			break
+		}
+		v = v.Field(num)
+	}
+	return v
+}
+
+func (e *encoder) structv(tag string, in reflect.Value) {
+	sinfo, err := getStructInfo(in.Type())
+	if err != nil {
+		panic(err)
+	}
+	e.mappingv(tag, func() {
+		for _, info := range sinfo.FieldsList {
+			var value reflect.Value
+			if info.Inline == nil {
+				value = in.Field(info.Num)
+			} else {
+				value = e.fieldByIndex(in, info.Inline)
+				if !value.IsValid() {
+					continue
+				}
+			}
+			if info.OmitEmpty && isZero(value) {
+				continue
+			}
+			e.marshal("", reflect.ValueOf(info.Key))
+			e.flow = info.Flow
+			e.marshal("", value)
+		}
+		if sinfo.InlineMap >= 0 {
+			m := in.Field(sinfo.InlineMap)
+			if m.Len() > 0 {
+				e.flow = false
+				keys := keyList(m.MapKeys())
+				sort.Sort(keys)
+				for _, k := range keys {
+					if _, found := sinfo.FieldsMap[k.String()]; found {
+						panic(fmt.Sprintf("cannot have key %q in inlined map: conflicts with struct field", k.String()))
+					}
+					e.marshal("", k)
+					e.flow = false
+					e.marshal("", m.MapIndex(k))
+				}
+			}
+		}
+	})
+}
+
+func (e *encoder) mappingv(tag string, f func()) {
+	implicit := tag == ""
+	style := yaml_BLOCK_MAPPING_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_MAPPING_STYLE
+	}
+	yaml_mapping_start_event_initialize(&e.event, nil, []byte(tag), implicit, style)
+	e.emit()
+	f()
+	yaml_mapping_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) slicev(tag string, in reflect.Value) {
+	implicit := tag == ""
+	style := yaml_BLOCK_SEQUENCE_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_SEQUENCE_STYLE
+	}
+	e.must(yaml_sequence_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
+	e.emit()
+	n := in.Len()
+	for i := 0; i < n; i++ {
+		e.marshal("", in.Index(i))
+	}
+	e.must(yaml_sequence_end_event_initialize(&e.event))
+	e.emit()
+}
+
+// isBase60 returns whether s is in base 60 notation as defined in YAML 1.1.
+//
+// The base 60 float notation in YAML 1.1 is a terrible idea and is unsupported
+// in YAML 1.2 and by this package, but these should be marshalled quoted for
+// the time being for compatibility with other parsers.
+func isBase60Float(s string) (result bool) {
+	// Fast path.
+	if s == "" {
+		return false
+	}
+	c := s[0]
+	if !(c == '+' || c == '-' || c >= '0' && c <= '9') || strings.IndexByte(s, ':') < 0 {
+		return false
+	}
+	// Do the full match.
+	return base60float.MatchString(s)
+}
+
+// From http://yaml.org/type/float.html, except the regular expression there
+// is bogus. In practice parsers do not enforce the "\.[0-9_]*" suffix.
+var base60float = regexp.MustCompile(`^[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+(?:\.[0-9_]*)?$`)
+
+// isOldBool returns whether s is bool notation as defined in YAML 1.1.
+//
+// We continue to force strings that YAML 1.1 would interpret as booleans to be
+// rendered as quotes strings so that the marshalled output valid for YAML 1.1
+// parsing.
+func isOldBool(s string) (result bool) {
+	switch s {
+	case "y", "Y", "yes", "Yes", "YES", "on", "On", "ON",
+		"n", "N", "no", "No", "NO", "off", "Off", "OFF":
+		return true
+	default:
+		return false
+	}
+}
+
+func (e *encoder) stringv(tag string, in reflect.Value) {
+	var style yaml_scalar_style_t
+	s := in.String()
+	canUsePlain := true
+	switch {
+	case !utf8.ValidString(s):
+		if tag == binaryTag {
+			failf("explicitly tagged !!binary data must be base64-encoded")
+		}
+		if tag != "" {
+			failf("cannot marshal invalid UTF-8 data as %s", shortTag(tag))
+		}
+		// It can't be encoded directly as YAML so use a binary tag
+		// and encode it as base64.
+		tag = binaryTag
+		s = encodeBase64(s)
+	case tag == "":
+		// Check to see if it would resolve to a specific
+		// tag when encoded unquoted. If it doesn't,
+		// there's no need to quote it.
+		rtag, _ := resolve("", s)
+		canUsePlain = rtag == strTag && !(isBase60Float(s) || isOldBool(s))
+	}
+	// Note: it's possible for user code to emit invalid YAML
+	// if they explicitly specify a tag and a string containing
+	// text that's incompatible with that tag.
+	switch {
+	case strings.Contains(s, "\n"):
+		if e.flow {
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		} else {
+			style = yaml_LITERAL_SCALAR_STYLE
+		}
+	case canUsePlain:
+		style = yaml_PLAIN_SCALAR_STYLE
+	default:
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+	e.emitScalar(s, "", tag, style, nil, nil, nil, nil)
+}
+
+func (e *encoder) boolv(tag string, in reflect.Value) {
+	var s string
+	if in.Bool() {
+		s = "true"
+	} else {
+		s = "false"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) intv(tag string, in reflect.Value) {
+	s := strconv.FormatInt(in.Int(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) uintv(tag string, in reflect.Value) {
+	s := strconv.FormatUint(in.Uint(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) timev(tag string, in reflect.Value) {
+	t := in.Interface().(time.Time)
+	s := t.Format(time.RFC3339Nano)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) floatv(tag string, in reflect.Value) {
+	// Issue #352: When formatting, use the precision of the underlying value
+	precision := 64
+	if in.Kind() == reflect.Float32 {
+		precision = 32
+	}
+
+	s := strconv.FormatFloat(in.Float(), 'g', -1, precision)
+	switch s {
+	case "+Inf":
+		s = ".inf"
+	case "-Inf":
+		s = "-.inf"
+	case "NaN":
+		s = ".nan"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) nilv() {
+	e.emitScalar("null", "", "", yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) emitScalar(value, anchor, tag string, style yaml_scalar_style_t, head, line, foot, tail []byte) {
+	// TODO Kill this function. Replace all initialize calls by their underlining Go literals.
+	implicit := tag == ""
+	if !implicit {
+		tag = longTag(tag)
+	}
+	e.must(yaml_scalar_event_initialize(&e.event, []byte(anchor), []byte(tag), []byte(value), implicit, implicit, style))
+	e.event.head_comment = head
+	e.event.line_comment = line
+	e.event.foot_comment = foot
+	e.event.tail_comment = tail
+	e.emit()
+}
+
+func (e *encoder) nodev(in reflect.Value) {
+	e.node(in.Interface().(*Node), "")
+}
+
+func (e *encoder) node(node *Node, tail string) {
+	// Zero nodes behave as nil.
+	if node.Kind == 0 && node.IsZero() {
+		e.nilv()
+		return
+	}
+
+	// If the tag was not explicitly requested, and dropping it won't change the
+	// implicit tag of the value, don't include it in the presentation.
+	var tag = node.Tag
+	var stag = shortTag(tag)
+	var forceQuoting bool
+	if tag != "" && node.Style&TaggedStyle == 0 {
+		if node.Kind == ScalarNode {
+			if stag == strTag && node.Style&(SingleQuotedStyle|DoubleQuotedStyle|LiteralStyle|FoldedStyle) != 0 {
+				tag = ""
+			} else {
+				rtag, _ := resolve("", node.Value)
+				if rtag == stag {
+					tag = ""
+				} else if stag == strTag {
+					tag = ""
+					forceQuoting = true
+				}
+			}
+		} else {
+			var rtag string
+			switch node.Kind {
+			case MappingNode:
+				rtag = mapTag
+			case SequenceNode:
+				rtag = seqTag
+			}
+			if rtag == stag {
+				tag = ""
+			}
+		}
+	}
+
+	switch node.Kind {
+	case DocumentNode:
+		yaml_document_start_event_initialize(&e.event, nil, nil, true)
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+		for _, node := range node.Content {
+			e.node(node, "")
+		}
+		yaml_document_end_event_initialize(&e.event, true)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case SequenceNode:
+		style := yaml_BLOCK_SEQUENCE_STYLE
+		if node.Style&FlowStyle != 0 {
+			style = yaml_FLOW_SEQUENCE_STYLE
+		}
+		e.must(yaml_sequence_start_event_initialize(&e.event, []byte(node.Anchor), []byte(longTag(tag)), tag == "", style))
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+		for _, node := range node.Content {
+			e.node(node, "")
+		}
+		e.must(yaml_sequence_end_event_initialize(&e.event))
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case MappingNode:
+		style := yaml_BLOCK_MAPPING_STYLE
+		if node.Style&FlowStyle != 0 {
+			style = yaml_FLOW_MAPPING_STYLE
+		}
+		yaml_mapping_start_event_initialize(&e.event, []byte(node.Anchor), []byte(longTag(tag)), tag == "", style)
+		e.event.tail_comment = []byte(tail)
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+
+		// The tail logic below moves the foot comment of prior keys to the following key,
+		// since the value for each key may be a nested structure and the foot needs to be
+		// processed only the entirety of the value is streamed. The last tail is processed
+		// with the mapping end event.
+		var tail string
+		for i := 0; i+1 < len(node.Content); i += 2 {
+			k := node.Content[i]
+			foot := k.FootComment
+			if foot != "" {
+				kopy := *k
+				kopy.FootComment = ""
+				k = &kopy
+			}
+			e.node(k, tail)
+			tail = foot
+
+			v := node.Content[i+1]
+			e.node(v, "")
+		}
+
+		yaml_mapping_end_event_initialize(&e.event)
+		e.event.tail_comment = []byte(tail)
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case AliasNode:
+		yaml_alias_event_initialize(&e.event, []byte(node.Value))
+		e.event.head_comment = []byte(node.HeadComment)
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case ScalarNode:
+		value := node.Value
+		if !utf8.ValidString(value) {
+			if stag == binaryTag {
+				failf("explicitly tagged !!binary data must be base64-encoded")
+			}
+			if stag != "" {
+				failf("cannot marshal invalid UTF-8 data as %s", stag)
+			}
+			// It can't be encoded directly as YAML so use a binary tag
+			// and encode it as base64.
+			tag = binaryTag
+			value = encodeBase64(value)
+		}
+
+		style := yaml_PLAIN_SCALAR_STYLE
+		switch {
+		case node.Style&DoubleQuotedStyle != 0:
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		case node.Style&SingleQuotedStyle != 0:
+			style = yaml_SINGLE_QUOTED_SCALAR_STYLE
+		case node.Style&LiteralStyle != 0:
+			style = yaml_LITERAL_SCALAR_STYLE
+		case node.Style&FoldedStyle != 0:
+			style = yaml_FOLDED_SCALAR_STYLE
+		case strings.Contains(value, "\n"):
+			style = yaml_LITERAL_SCALAR_STYLE
+		case forceQuoting:
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		}
+
+		e.emitScalar(value, node.Anchor, tag, style, []byte(node.HeadComment), []byte(node.LineComment), []byte(node.FootComment), []byte(tail))
+	default:
+		failf("cannot encode node with unknown kind %d", node.Kind)
+	}
+}

vendor/gopkg.in/yaml.v3/readerc.go

@@ -0,0 +1,434 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"io"
+)
+
+// Set the reader error and return 0.
+func yaml_parser_set_reader_error(parser *yaml_parser_t, problem string, offset int, value int) bool {
+	parser.error = yaml_READER_ERROR
+	parser.problem = problem
+	parser.problem_offset = offset
+	parser.problem_value = value
+	return false
+}
+
+// Byte order marks.
+const (
+	bom_UTF8    = "\xef\xbb\xbf"
+	bom_UTF16LE = "\xff\xfe"
+	bom_UTF16BE = "\xfe\xff"
+)
+
+// Determine the input stream encoding by checking the BOM symbol. If no BOM is
+// found, the UTF-8 encoding is assumed. Return 1 on success, 0 on failure.
+func yaml_parser_determine_encoding(parser *yaml_parser_t) bool {
+	// Ensure that we had enough bytes in the raw buffer.
+	for !parser.eof && len(parser.raw_buffer)-parser.raw_buffer_pos < 3 {
+		if !yaml_parser_update_raw_buffer(parser) {
+			return false
+		}
+	}
+
+	// Determine the encoding.
+	buf := parser.raw_buffer
+	pos := parser.raw_buffer_pos
+	avail := len(buf) - pos
+	if avail >= 2 && buf[pos] == bom_UTF16LE[0] && buf[pos+1] == bom_UTF16LE[1] {
+		parser.encoding = yaml_UTF16LE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 2 && buf[pos] == bom_UTF16BE[0] && buf[pos+1] == bom_UTF16BE[1] {
+		parser.encoding = yaml_UTF16BE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 3 && buf[pos] == bom_UTF8[0] && buf[pos+1] == bom_UTF8[1] && buf[pos+2] == bom_UTF8[2] {
+		parser.encoding = yaml_UTF8_ENCODING
+		parser.raw_buffer_pos += 3
+		parser.offset += 3
+	} else {
+		parser.encoding = yaml_UTF8_ENCODING
+	}
+	return true
+}
+
+// Update the raw buffer.
+func yaml_parser_update_raw_buffer(parser *yaml_parser_t) bool {
+	size_read := 0
+
+	// Return if the raw buffer is full.
+	if parser.raw_buffer_pos == 0 && len(parser.raw_buffer) == cap(parser.raw_buffer) {
+		return true
+	}
+
+	// Return on EOF.
+	if parser.eof {
+		return true
+	}
+
+	// Move the remaining bytes in the raw buffer to the beginning.
+	if parser.raw_buffer_pos > 0 && parser.raw_buffer_pos < len(parser.raw_buffer) {
+		copy(parser.raw_buffer, parser.raw_buffer[parser.raw_buffer_pos:])
+	}
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)-parser.raw_buffer_pos]
+	parser.raw_buffer_pos = 0
+
+	// Call the read handler to fill the buffer.
+	size_read, err := parser.read_handler(parser, parser.raw_buffer[len(parser.raw_buffer):cap(parser.raw_buffer)])
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)+size_read]
+	if err == io.EOF {
+		parser.eof = true
+	} else if err != nil {
+		return yaml_parser_set_reader_error(parser, "input error: "+err.Error(), parser.offset, -1)
+	}
+	return true
+}
+
+// Ensure that the buffer contains at least `length` characters.
+// Return true on success, false on failure.
+//
+// The length is supposed to be significantly less that the buffer size.
+func yaml_parser_update_buffer(parser *yaml_parser_t, length int) bool {
+	if parser.read_handler == nil {
+		panic("read handler must be set")
+	}
+
+	// [Go] This function was changed to guarantee the requested length size at EOF.
+	// The fact we need to do this is pretty awful, but the description above implies
+	// for that to be the case, and there are tests
+
+	// If the EOF flag is set and the raw buffer is empty, do nothing.
+	if parser.eof && parser.raw_buffer_pos == len(parser.raw_buffer) {
+		// [Go] ACTUALLY! Read the documentation of this function above.
+		// This is just broken. To return true, we need to have the
+		// given length in the buffer. Not doing that means every single
+		// check that calls this function to make sure the buffer has a
+		// given length is Go) panicking; or C) accessing invalid memory.
+		//return true
+	}
+
+	// Return if the buffer contains enough characters.
+	if parser.unread >= length {
+		return true
+	}
+
+	// Determine the input encoding if it is not known yet.
+	if parser.encoding == yaml_ANY_ENCODING {
+		if !yaml_parser_determine_encoding(parser) {
+			return false
+		}
+	}
+
+	// Move the unread characters to the beginning of the buffer.
+	buffer_len := len(parser.buffer)
+	if parser.buffer_pos > 0 && parser.buffer_pos < buffer_len {
+		copy(parser.buffer, parser.buffer[parser.buffer_pos:])
+		buffer_len -= parser.buffer_pos
+		parser.buffer_pos = 0
+	} else if parser.buffer_pos == buffer_len {
+		buffer_len = 0
+		parser.buffer_pos = 0
+	}
+
+	// Open the whole buffer for writing, and cut it before returning.
+	parser.buffer = parser.buffer[:cap(parser.buffer)]
+
+	// Fill the buffer until it has enough characters.
+	first := true
+	for parser.unread < length {
+
+		// Fill the raw buffer if necessary.
+		if !first || parser.raw_buffer_pos == len(parser.raw_buffer) {
+			if !yaml_parser_update_raw_buffer(parser) {
+				parser.buffer = parser.buffer[:buffer_len]
+				return false
+			}
+		}
+		first = false
+
+		// Decode the raw buffer.
+	inner:
+		for parser.raw_buffer_pos != len(parser.raw_buffer) {
+			var value rune
+			var width int
+
+			raw_unread := len(parser.raw_buffer) - parser.raw_buffer_pos
+
+			// Decode the next character.
+			switch parser.encoding {
+			case yaml_UTF8_ENCODING:
+				// Decode a UTF-8 character.  Check RFC 3629
+				// (http://www.ietf.org/rfc/rfc3629.txt) for more details.
+				//
+				// The following table (taken from the RFC) is used for
+				// decoding.
+				//
+				//    Char. number range |        UTF-8 octet sequence
+				//      (hexadecimal)    |              (binary)
+				//   --------------------+------------------------------------
+				//   0000 0000-0000 007F | 0xxxxxxx
+				//   0000 0080-0000 07FF | 110xxxxx 10xxxxxx
+				//   0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
+				//   0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				//
+				// Additionally, the characters in the range 0xD800-0xDFFF
+				// are prohibited as they are reserved for use with UTF-16
+				// surrogate pairs.
+
+				// Determine the length of the UTF-8 sequence.
+				octet := parser.raw_buffer[parser.raw_buffer_pos]
+				switch {
+				case octet&0x80 == 0x00:
+					width = 1
+				case octet&0xE0 == 0xC0:
+					width = 2
+				case octet&0xF0 == 0xE0:
+					width = 3
+				case octet&0xF8 == 0xF0:
+					width = 4
+				default:
+					// The leading octet is invalid.
+					return yaml_parser_set_reader_error(parser,
+						"invalid leading UTF-8 octet",
+						parser.offset, int(octet))
+				}
+
+				// Check if the raw buffer contains an incomplete character.
+				if width > raw_unread {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-8 octet sequence",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Decode the leading octet.
+				switch {
+				case octet&0x80 == 0x00:
+					value = rune(octet & 0x7F)
+				case octet&0xE0 == 0xC0:
+					value = rune(octet & 0x1F)
+				case octet&0xF0 == 0xE0:
+					value = rune(octet & 0x0F)
+				case octet&0xF8 == 0xF0:
+					value = rune(octet & 0x07)
+				default:
+					value = 0
+				}
+
+				// Check and decode the trailing octets.
+				for k := 1; k < width; k++ {
+					octet = parser.raw_buffer[parser.raw_buffer_pos+k]
+
+					// Check if the octet is valid.
+					if (octet & 0xC0) != 0x80 {
+						return yaml_parser_set_reader_error(parser,
+							"invalid trailing UTF-8 octet",
+							parser.offset+k, int(octet))
+					}
+
+					// Decode the octet.
+					value = (value << 6) + rune(octet&0x3F)
+				}
+
+				// Check the length of the sequence against the value.
+				switch {
+				case width == 1:
+				case width == 2 && value >= 0x80:
+				case width == 3 && value >= 0x800:
+				case width == 4 && value >= 0x10000:
+				default:
+					return yaml_parser_set_reader_error(parser,
+						"invalid length of a UTF-8 sequence",
+						parser.offset, -1)
+				}
+
+				// Check the range of the value.
+				if value >= 0xD800 && value <= 0xDFFF || value > 0x10FFFF {
+					return yaml_parser_set_reader_error(parser,
+						"invalid Unicode character",
+						parser.offset, int(value))
+				}
+
+			case yaml_UTF16LE_ENCODING, yaml_UTF16BE_ENCODING:
+				var low, high int
+				if parser.encoding == yaml_UTF16LE_ENCODING {
+					low, high = 0, 1
+				} else {
+					low, high = 1, 0
+				}
+
+				// The UTF-16 encoding is not as simple as one might
+				// naively think.  Check RFC 2781
+				// (http://www.ietf.org/rfc/rfc2781.txt).
+				//
+				// Normally, two subsequent bytes describe a Unicode
+				// character.  However a special technique (called a
+				// surrogate pair) is used for specifying character
+				// values larger than 0xFFFF.
+				//
+				// A surrogate pair consists of two pseudo-characters:
+				//      high surrogate area (0xD800-0xDBFF)
+				//      low surrogate area (0xDC00-0xDFFF)
+				//
+				// The following formulas are used for decoding
+				// and encoding characters using surrogate pairs:
+				//
+				//  U  = U' + 0x10000   (0x01 00 00 <= U <= 0x10 FF FF)
+				//  U' = yyyyyyyyyyxxxxxxxxxx   (0 <= U' <= 0x0F FF FF)
+				//  W1 = 110110yyyyyyyyyy
+				//  W2 = 110111xxxxxxxxxx
+				//
+				// where U is the character value, W1 is the high surrogate
+				// area, W2 is the low surrogate area.
+
+				// Check for incomplete UTF-16 character.
+				if raw_unread < 2 {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-16 character",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Get the character.
+				value = rune(parser.raw_buffer[parser.raw_buffer_pos+low]) +
+					(rune(parser.raw_buffer[parser.raw_buffer_pos+high]) << 8)
+
+				// Check for unexpected low surrogate area.
+				if value&0xFC00 == 0xDC00 {
+					return yaml_parser_set_reader_error(parser,
+						"unexpected low surrogate area",
+						parser.offset, int(value))
+				}
+
+				// Check for a high surrogate area.
+				if value&0xFC00 == 0xD800 {
+					width = 4
+
+					// Check for incomplete surrogate pair.
+					if raw_unread < 4 {
+						if parser.eof {
+							return yaml_parser_set_reader_error(parser,
+								"incomplete UTF-16 surrogate pair",
+								parser.offset, -1)
+						}
+						break inner
+					}
+
+					// Get the next character.
+					value2 := rune(parser.raw_buffer[parser.raw_buffer_pos+low+2]) +
+						(rune(parser.raw_buffer[parser.raw_buffer_pos+high+2]) << 8)
+
+					// Check for a low surrogate area.
+					if value2&0xFC00 != 0xDC00 {
+						return yaml_parser_set_reader_error(parser,
+							"expected low surrogate area",
+							parser.offset+2, int(value2))
+					}
+
+					// Generate the value of the surrogate pair.
+					value = 0x10000 + ((value & 0x3FF) << 10) + (value2 & 0x3FF)
+				} else {
+					width = 2
+				}
+
+			default:
+				panic("impossible")
+			}
+
+			// Check if the character is in the allowed range:
+			//      #x9 | #xA | #xD | [#x20-#x7E]               (8 bit)
+			//      | #x85 | [#xA0-#xD7FF] | [#xE000-#xFFFD]    (16 bit)
+			//      | [#x10000-#x10FFFF]                        (32 bit)
+			switch {
+			case value == 0x09:
+			case value == 0x0A:
+			case value == 0x0D:
+			case value >= 0x20 && value <= 0x7E:
+			case value == 0x85:
+			case value >= 0xA0 && value <= 0xD7FF:
+			case value >= 0xE000 && value <= 0xFFFD:
+			case value >= 0x10000 && value <= 0x10FFFF:
+			default:
+				return yaml_parser_set_reader_error(parser,
+					"control characters are not allowed",
+					parser.offset, int(value))
+			}
+
+			// Move the raw pointers.
+			parser.raw_buffer_pos += width
+			parser.offset += width
+
+			// Finally put the character into the buffer.
+			if value <= 0x7F {
+				// 0000 0000-0000 007F . 0xxxxxxx
+				parser.buffer[buffer_len+0] = byte(value)
+				buffer_len += 1
+			} else if value <= 0x7FF {
+				// 0000 0080-0000 07FF . 110xxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xC0 + (value >> 6))
+				parser.buffer[buffer_len+1] = byte(0x80 + (value & 0x3F))
+				buffer_len += 2
+			} else if value <= 0xFFFF {
+				// 0000 0800-0000 FFFF . 1110xxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xE0 + (value >> 12))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + (value & 0x3F))
+				buffer_len += 3
+			} else {
+				// 0001 0000-0010 FFFF . 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xF0 + (value >> 18))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 12) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+3] = byte(0x80 + (value & 0x3F))
+				buffer_len += 4
+			}
+
+			parser.unread++
+		}
+
+		// On EOF, put NUL into the buffer and return.
+		if parser.eof {
+			parser.buffer[buffer_len] = 0
+			buffer_len++
+			parser.unread++
+			break
+		}
+	}
+	// [Go] Read the documentation of this function above. To return true,
+	// we need to have the given length in the buffer. Not doing that means
+	// every single check that calls this function to make sure the buffer
+	// has a given length is Go) panicking; or C) accessing invalid memory.
+	// This happens here due to the EOF above breaking early.
+	for buffer_len < length {
+		parser.buffer[buffer_len] = 0
+		buffer_len++
+	}
+	parser.buffer = parser.buffer[:buffer_len]
+	return true
+}

vendor/gopkg.in/yaml.v3/resolve.go

@@ -0,0 +1,326 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"encoding/base64"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type resolveMapItem struct {
+	value interface{}
+	tag   string
+}
+
+var resolveTable = make([]byte, 256)
+var resolveMap = make(map[string]resolveMapItem)
+
+func init() {
+	t := resolveTable
+	t[int('+')] = 'S' // Sign
+	t[int('-')] = 'S'
+	for _, c := range "0123456789" {
+		t[int(c)] = 'D' // Digit
+	}
+	for _, c := range "yYnNtTfFoO~" {
+		t[int(c)] = 'M' // In map
+	}
+	t[int('.')] = '.' // Float (potentially in map)
+
+	var resolveMapList = []struct {
+		v   interface{}
+		tag string
+		l   []string
+	}{
+		{true, boolTag, []string{"true", "True", "TRUE"}},
+		{false, boolTag, []string{"false", "False", "FALSE"}},
+		{nil, nullTag, []string{"", "~", "null", "Null", "NULL"}},
+		{math.NaN(), floatTag, []string{".nan", ".NaN", ".NAN"}},
+		{math.Inf(+1), floatTag, []string{".inf", ".Inf", ".INF"}},
+		{math.Inf(+1), floatTag, []string{"+.inf", "+.Inf", "+.INF"}},
+		{math.Inf(-1), floatTag, []string{"-.inf", "-.Inf", "-.INF"}},
+		{"<<", mergeTag, []string{"<<"}},
+	}
+
+	m := resolveMap
+	for _, item := range resolveMapList {
+		for _, s := range item.l {
+			m[s] = resolveMapItem{item.v, item.tag}
+		}
+	}
+}
+
+const (
+	nullTag      = "!!null"
+	boolTag      = "!!bool"
+	strTag       = "!!str"
+	intTag       = "!!int"
+	floatTag     = "!!float"
+	timestampTag = "!!timestamp"
+	seqTag       = "!!seq"
+	mapTag       = "!!map"
+	binaryTag    = "!!binary"
+	mergeTag     = "!!merge"
+)
+
+var longTags = make(map[string]string)
+var shortTags = make(map[string]string)
+
+func init() {
+	for _, stag := range []string{nullTag, boolTag, strTag, intTag, floatTag, timestampTag, seqTag, mapTag, binaryTag, mergeTag} {
+		ltag := longTag(stag)
+		longTags[stag] = ltag
+		shortTags[ltag] = stag
+	}
+}
+
+const longTagPrefix = "tag:yaml.org,2002:"
+
+func shortTag(tag string) string {
+	if strings.HasPrefix(tag, longTagPrefix) {
+		if stag, ok := shortTags[tag]; ok {
+			return stag
+		}
+		return "!!" + tag[len(longTagPrefix):]
+	}
+	return tag
+}
+
+func longTag(tag string) string {
+	if strings.HasPrefix(tag, "!!") {
+		if ltag, ok := longTags[tag]; ok {
+			return ltag
+		}
+		return longTagPrefix + tag[2:]
+	}
+	return tag
+}
+
+func resolvableTag(tag string) bool {
+	switch tag {
+	case "", strTag, boolTag, intTag, floatTag, nullTag, timestampTag:
+		return true
+	}
+	return false
+}
+
+var yamlStyleFloat = regexp.MustCompile(`^[-+]?(\.[0-9]+|[0-9]+(\.[0-9]*)?)([eE][-+]?[0-9]+)?$`)
+
+func resolve(tag string, in string) (rtag string, out interface{}) {
+	tag = shortTag(tag)
+	if !resolvableTag(tag) {
+		return tag, in
+	}
+
+	defer func() {
+		switch tag {
+		case "", rtag, strTag, binaryTag:
+			return
+		case floatTag:
+			if rtag == intTag {
+				switch v := out.(type) {
+				case int64:
+					rtag = floatTag
+					out = float64(v)
+					return
+				case int:
+					rtag = floatTag
+					out = float64(v)
+					return
+				}
+			}
+		}
+		failf("cannot decode %s `%s` as a %s", shortTag(rtag), in, shortTag(tag))
+	}()
+
+	// Any data is accepted as a !!str or !!binary.
+	// Otherwise, the prefix is enough of a hint about what it might be.
+	hint := byte('N')
+	if in != "" {
+		hint = resolveTable[in[0]]
+	}
+	if hint != 0 && tag != strTag && tag != binaryTag {
+		// Handle things we can lookup in a map.
+		if item, ok := resolveMap[in]; ok {
+			return item.tag, item.value
+		}
+
+		// Base 60 floats are a bad idea, were dropped in YAML 1.2, and
+		// are purposefully unsupported here. They're still quoted on
+		// the way out for compatibility with other parser, though.
+
+		switch hint {
+		case 'M':
+			// We've already checked the map above.
+
+		case '.':
+			// Not in the map, so maybe a normal float.
+			floatv, err := strconv.ParseFloat(in, 64)
+			if err == nil {
+				return floatTag, floatv
+			}
+
+		case 'D', 'S':
+			// Int, float, or timestamp.
+			// Only try values as a timestamp if the value is unquoted or there's an explicit
+			// !!timestamp tag.
+			if tag == "" || tag == timestampTag {
+				t, ok := parseTimestamp(in)
+				if ok {
+					return timestampTag, t
+				}
+			}
+
+			plain := strings.Replace(in, "_", "", -1)
+			intv, err := strconv.ParseInt(plain, 0, 64)
+			if err == nil {
+				if intv == int64(int(intv)) {
+					return intTag, int(intv)
+				} else {
+					return intTag, intv
+				}
+			}
+			uintv, err := strconv.ParseUint(plain, 0, 64)
+			if err == nil {
+				return intTag, uintv
+			}
+			if yamlStyleFloat.MatchString(plain) {
+				floatv, err := strconv.ParseFloat(plain, 64)
+				if err == nil {
+					return floatTag, floatv
+				}
+			}
+			if strings.HasPrefix(plain, "0b") {
+				intv, err := strconv.ParseInt(plain[2:], 2, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 2, 64)
+				if err == nil {
+					return intTag, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0b") {
+				intv, err := strconv.ParseInt("-"+plain[3:], 2, 64)
+				if err == nil {
+					if true || intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+			}
+			// Octals as introduced in version 1.2 of the spec.
+			// Octals from the 1.1 spec, spelled as 0777, are still
+			// decoded by default in v3 as well for compatibility.
+			// May be dropped in v4 depending on how usage evolves.
+			if strings.HasPrefix(plain, "0o") {
+				intv, err := strconv.ParseInt(plain[2:], 8, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 8, 64)
+				if err == nil {
+					return intTag, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0o") {
+				intv, err := strconv.ParseInt("-"+plain[3:], 8, 64)
+				if err == nil {
+					if true || intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+			}
+		default:
+			panic("internal error: missing handler for resolver table: " + string(rune(hint)) + " (with " + in + ")")
+		}
+	}
+	return strTag, in
+}
+
+// encodeBase64 encodes s as base64 that is broken up into multiple lines
+// as appropriate for the resulting length.
+func encodeBase64(s string) string {
+	const lineLen = 70
+	encLen := base64.StdEncoding.EncodedLen(len(s))
+	lines := encLen/lineLen + 1
+	buf := make([]byte, encLen*2+lines)
+	in := buf[0:encLen]
+	out := buf[encLen:]
+	base64.StdEncoding.Encode(in, []byte(s))
+	k := 0
+	for i := 0; i < len(in); i += lineLen {
+		j := i + lineLen
+		if j > len(in) {
+			j = len(in)
+		}
+		k += copy(out[k:], in[i:j])
+		if lines > 1 {
+			out[k] = '\n'
+			k++
+		}
+	}
+	return string(out[:k])
+}
+
+// This is a subset of the formats allowed by the regular expression
+// defined at http://yaml.org/type/timestamp.html.
+var allowedTimestampFormats = []string{
+	"2006-1-2T15:4:5.999999999Z07:00", // RCF3339Nano with short date fields.
+	"2006-1-2t15:4:5.999999999Z07:00", // RFC3339Nano with short date fields and lower-case "t".
+	"2006-1-2 15:4:5.999999999",       // space separated with no time zone
+	"2006-1-2",                        // date only
+	// Notable exception: time.Parse cannot handle: "2001-12-14 21:59:43.10 -5"
+	// from the set of examples.
+}
+
+// parseTimestamp parses s as a timestamp string and
+// returns the timestamp and reports whether it succeeded.
+// Timestamp formats are defined at http://yaml.org/type/timestamp.html
+func parseTimestamp(s string) (time.Time, bool) {
+	// TODO write code to check all the formats supported by
+	// http://yaml.org/type/timestamp.html instead of using time.Parse.
+
+	// Quick check: all date formats start with YYYY-.
+	i := 0
+	for ; i < len(s); i++ {
+		if c := s[i]; c < '0' || c > '9' {
+			break
+		}
+	}
+	if i != 4 || i == len(s) || s[i] != '-' {
+		return time.Time{}, false
+	}
+	for _, format := range allowedTimestampFormats {
+		if t, err := time.Parse(format, s); err == nil {
+			return t, true
+		}
+	}
+	return time.Time{}, false
+}

vendor/gopkg.in/yaml.v3/sorter.go

@@ -0,0 +1,134 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"reflect"
+	"unicode"
+)
+
+type keyList []reflect.Value
+
+func (l keyList) Len() int      { return len(l) }
+func (l keyList) Swap(i, j int) { l[i], l[j] = l[j], l[i] }
+func (l keyList) Less(i, j int) bool {
+	a := l[i]
+	b := l[j]
+	ak := a.Kind()
+	bk := b.Kind()
+	for (ak == reflect.Interface || ak == reflect.Ptr) && !a.IsNil() {
+		a = a.Elem()
+		ak = a.Kind()
+	}
+	for (bk == reflect.Interface || bk == reflect.Ptr) && !b.IsNil() {
+		b = b.Elem()
+		bk = b.Kind()
+	}
+	af, aok := keyFloat(a)
+	bf, bok := keyFloat(b)
+	if aok && bok {
+		if af != bf {
+			return af < bf
+		}
+		if ak != bk {
+			return ak < bk
+		}
+		return numLess(a, b)
+	}
+	if ak != reflect.String || bk != reflect.String {
+		return ak < bk
+	}
+	ar, br := []rune(a.String()), []rune(b.String())
+	digits := false
+	for i := 0; i < len(ar) && i < len(br); i++ {
+		if ar[i] == br[i] {
+			digits = unicode.IsDigit(ar[i])
+			continue
+		}
+		al := unicode.IsLetter(ar[i])
+		bl := unicode.IsLetter(br[i])
+		if al && bl {
+			return ar[i] < br[i]
+		}
+		if al || bl {
+			if digits {
+				return al
+			} else {
+				return bl
+			}
+		}
+		var ai, bi int
+		var an, bn int64
+		if ar[i] == '0' || br[i] == '0' {
+			for j := i - 1; j >= 0 && unicode.IsDigit(ar[j]); j-- {
+				if ar[j] != '0' {
+					an = 1
+					bn = 1
+					break
+				}
+			}
+		}
+		for ai = i; ai < len(ar) && unicode.IsDigit(ar[ai]); ai++ {
+			an = an*10 + int64(ar[ai]-'0')
+		}
+		for bi = i; bi < len(br) && unicode.IsDigit(br[bi]); bi++ {
+			bn = bn*10 + int64(br[bi]-'0')
+		}
+		if an != bn {
+			return an < bn
+		}
+		if ai != bi {
+			return ai < bi
+		}
+		return ar[i] < br[i]
+	}
+	return len(ar) < len(br)
+}
+
+// keyFloat returns a float value for v if it is a number/bool
+// and whether it is a number/bool or not.
+func keyFloat(v reflect.Value) (f float64, ok bool) {
+	switch v.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return float64(v.Int()), true
+	case reflect.Float32, reflect.Float64:
+		return v.Float(), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return float64(v.Uint()), true
+	case reflect.Bool:
+		if v.Bool() {
+			return 1, true
+		}
+		return 0, true
+	}
+	return 0, false
+}
+
+// numLess returns whether a < b.
+// a and b must necessarily have the same kind.
+func numLess(a, b reflect.Value) bool {
+	switch a.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return a.Int() < b.Int()
+	case reflect.Float32, reflect.Float64:
+		return a.Float() < b.Float()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return a.Uint() < b.Uint()
+	case reflect.Bool:
+		return !a.Bool() && b.Bool()
+	}
+	panic("not a number")
+}

vendor/gopkg.in/yaml.v3/writerc.go

@@ -0,0 +1,48 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+// Set the writer error and return false.
+func yaml_emitter_set_writer_error(emitter *yaml_emitter_t, problem string) bool {
+	emitter.error = yaml_WRITER_ERROR
+	emitter.problem = problem
+	return false
+}
+
+// Flush the output buffer.
+func yaml_emitter_flush(emitter *yaml_emitter_t) bool {
+	if emitter.write_handler == nil {
+		panic("write handler not set")
+	}
+
+	// Check if the buffer is empty.
+	if emitter.buffer_pos == 0 {
+		return true
+	}
+
+	if err := emitter.write_handler(emitter, emitter.buffer[:emitter.buffer_pos]); err != nil {
+		return yaml_emitter_set_writer_error(emitter, "write error: "+err.Error())
+	}
+	emitter.buffer_pos = 0
+	return true
+}

vendor/gopkg.in/yaml.v3/yaml.go

@@ -0,0 +1,698 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package yaml implements YAML support for the Go language.
+//
+// Source code and other details for the project are available at GitHub:
+//
+//   https://github.com/go-yaml/yaml
+//
+package yaml
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+	"sync"
+	"unicode/utf8"
+)
+
+// The Unmarshaler interface may be implemented by types to customize their
+// behavior when being unmarshaled from a YAML document.
+type Unmarshaler interface {
+	UnmarshalYAML(value *Node) error
+}
+
+type obsoleteUnmarshaler interface {
+	UnmarshalYAML(unmarshal func(interface{}) error) error
+}
+
+// The Marshaler interface may be implemented by types to customize their
+// behavior when being marshaled into a YAML document. The returned value
+// is marshaled in place of the original value implementing Marshaler.
+//
+// If an error is returned by MarshalYAML, the marshaling procedure stops
+// and returns with the provided error.
+type Marshaler interface {
+	MarshalYAML() (interface{}, error)
+}
+
+// Unmarshal decodes the first document found within the in byte slice
+// and assigns decoded values into the out value.
+//
+// Maps and pointers (to a struct, string, int, etc) are accepted as out
+// values. If an internal pointer within a struct is not initialized,
+// the yaml package will initialize it if necessary for unmarshalling
+// the provided data. The out parameter must not be nil.
+//
+// The type of the decoded values should be compatible with the respective
+// values in out. If one or more values cannot be decoded due to a type
+// mismatches, decoding continues partially until the end of the YAML
+// content, and a *yaml.TypeError is returned with details for all
+// missed values.
+//
+// Struct fields are only unmarshalled if they are exported (have an
+// upper case first letter), and are unmarshalled using the field name
+// lowercased as the default key. Custom keys may be defined via the
+// "yaml" name in the field tag: the content preceding the first comma
+// is used as the key, and the following comma-separated options are
+// used to tweak the marshalling process (see Marshal).
+// Conflicting names result in a runtime error.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     var t T
+//     yaml.Unmarshal([]byte("a: 1\nb: 2"), &t)
+//
+// See the documentation of Marshal for the format of tags and a list of
+// supported tag options.
+//
+func Unmarshal(in []byte, out interface{}) (err error) {
+	return unmarshal(in, out, false)
+}
+
+// A Decoder reads and decodes YAML values from an input stream.
+type Decoder struct {
+	parser      *parser
+	knownFields bool
+}
+
+// NewDecoder returns a new decoder that reads from r.
+//
+// The decoder introduces its own buffering and may read
+// data from r beyond the YAML values requested.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{
+		parser: newParserFromReader(r),
+	}
+}
+
+// KnownFields ensures that the keys in decoded mappings to
+// exist as fields in the struct being decoded into.
+func (dec *Decoder) KnownFields(enable bool) {
+	dec.knownFields = enable
+}
+
+// Decode reads the next YAML-encoded value from its input
+// and stores it in the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (dec *Decoder) Decode(v interface{}) (err error) {
+	d := newDecoder()
+	d.knownFields = dec.knownFields
+	defer handleErr(&err)
+	node := dec.parser.parse()
+	if node == nil {
+		return io.EOF
+	}
+	out := reflect.ValueOf(v)
+	if out.Kind() == reflect.Ptr && !out.IsNil() {
+		out = out.Elem()
+	}
+	d.unmarshal(node, out)
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Decode decodes the node and stores its data into the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (n *Node) Decode(v interface{}) (err error) {
+	d := newDecoder()
+	defer handleErr(&err)
+	out := reflect.ValueOf(v)
+	if out.Kind() == reflect.Ptr && !out.IsNil() {
+		out = out.Elem()
+	}
+	d.unmarshal(n, out)
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+func unmarshal(in []byte, out interface{}, strict bool) (err error) {
+	defer handleErr(&err)
+	d := newDecoder()
+	p := newParser(in)
+	defer p.destroy()
+	node := p.parse()
+	if node != nil {
+		v := reflect.ValueOf(out)
+		if v.Kind() == reflect.Ptr && !v.IsNil() {
+			v = v.Elem()
+		}
+		d.unmarshal(node, v)
+	}
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Marshal serializes the value provided into a YAML document. The structure
+// of the generated document will reflect the structure of the value itself.
+// Maps and pointers (to struct, string, int, etc) are accepted as the in value.
+//
+// Struct fields are only marshalled if they are exported (have an upper case
+// first letter), and are marshalled using the field name lowercased as the
+// default key. Custom keys may be defined via the "yaml" name in the field
+// tag: the content preceding the first comma is used as the key, and the
+// following comma-separated options are used to tweak the marshalling process.
+// Conflicting names result in a runtime error.
+//
+// The field tag format accepted is:
+//
+//     `(...) yaml:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported:
+//
+//     omitempty    Only include the field if it's not set to the zero
+//                  value for the type or to empty slices or maps.
+//                  Zero valued structs will be omitted if all their public
+//                  fields are zero, unless they implement an IsZero
+//                  method (see the IsZeroer interface type), in which
+//                  case the field will be excluded if IsZero returns true.
+//
+//     flow         Marshal using a flow style (useful for structs,
+//                  sequences and maps).
+//
+//     inline       Inline the field, which must be a struct or a map,
+//                  causing all of its fields or keys to be processed as if
+//                  they were part of the outer struct. For maps, keys must
+//                  not conflict with the yaml keys of other struct fields.
+//
+// In addition, if the key is "-", the field is ignored.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     yaml.Marshal(&T{B: 2}) // Returns "b: 2\n"
+//     yaml.Marshal(&T{F: 1}} // Returns "a: 1\nb: 0\n"
+//
+func Marshal(in interface{}) (out []byte, err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshalDoc("", reflect.ValueOf(in))
+	e.finish()
+	out = e.out
+	return
+}
+
+// An Encoder writes YAML values to an output stream.
+type Encoder struct {
+	encoder *encoder
+}
+
+// NewEncoder returns a new encoder that writes to w.
+// The Encoder should be closed after use to flush all data
+// to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		encoder: newEncoderWithWriter(w),
+	}
+}
+
+// Encode writes the YAML encoding of v to the stream.
+// If multiple items are encoded to the stream, the
+// second and subsequent document will be preceded
+// with a "---" document separator, but the first will not.
+//
+// See the documentation for Marshal for details about the conversion of Go
+// values to YAML.
+func (e *Encoder) Encode(v interface{}) (err error) {
+	defer handleErr(&err)
+	e.encoder.marshalDoc("", reflect.ValueOf(v))
+	return nil
+}
+
+// Encode encodes value v and stores its representation in n.
+//
+// See the documentation for Marshal for details about the
+// conversion of Go values into YAML.
+func (n *Node) Encode(v interface{}) (err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshalDoc("", reflect.ValueOf(v))
+	e.finish()
+	p := newParser(e.out)
+	p.textless = true
+	defer p.destroy()
+	doc := p.parse()
+	*n = *doc.Content[0]
+	return nil
+}
+
+// SetIndent changes the used indentation used when encoding.
+func (e *Encoder) SetIndent(spaces int) {
+	if spaces < 0 {
+		panic("yaml: cannot indent to a negative number of spaces")
+	}
+	e.encoder.indent = spaces
+}
+
+// Close closes the encoder by writing any remaining data.
+// It does not write a stream terminating string "...".
+func (e *Encoder) Close() (err error) {
+	defer handleErr(&err)
+	e.encoder.finish()
+	return nil
+}
+
+func handleErr(err *error) {
+	if v := recover(); v != nil {
+		if e, ok := v.(yamlError); ok {
+			*err = e.err
+		} else {
+			panic(v)
+		}
+	}
+}
+
+type yamlError struct {
+	err error
+}
+
+func fail(err error) {
+	panic(yamlError{err})
+}
+
+func failf(format string, args ...interface{}) {
+	panic(yamlError{fmt.Errorf("yaml: "+format, args...)})
+}
+
+// A TypeError is returned by Unmarshal when one or more fields in
+// the YAML document cannot be properly decoded into the requested
+// types. When this error is returned, the value is still
+// unmarshaled partially.
+type TypeError struct {
+	Errors []string
+}
+
+func (e *TypeError) Error() string {
+	return fmt.Sprintf("yaml: unmarshal errors:\n  %s", strings.Join(e.Errors, "\n  "))
+}
+
+type Kind uint32
+
+const (
+	DocumentNode Kind = 1 << iota
+	SequenceNode
+	MappingNode
+	ScalarNode
+	AliasNode
+)
+
+type Style uint32
+
+const (
+	TaggedStyle Style = 1 << iota
+	DoubleQuotedStyle
+	SingleQuotedStyle
+	LiteralStyle
+	FoldedStyle
+	FlowStyle
+)
+
+// Node represents an element in the YAML document hierarchy. While documents
+// are typically encoded and decoded into higher level types, such as structs
+// and maps, Node is an intermediate representation that allows detailed
+// control over the content being decoded or encoded.
+//
+// It's worth noting that although Node offers access into details such as
+// line numbers, colums, and comments, the content when re-encoded will not
+// have its original textual representation preserved. An effort is made to
+// render the data plesantly, and to preserve comments near the data they
+// describe, though.
+//
+// Values that make use of the Node type interact with the yaml package in the
+// same way any other type would do, by encoding and decoding yaml data
+// directly or indirectly into them.
+//
+// For example:
+//
+//     var person struct {
+//             Name    string
+//             Address yaml.Node
+//     }
+//     err := yaml.Unmarshal(data, &person)
+// 
+// Or by itself:
+//
+//     var person Node
+//     err := yaml.Unmarshal(data, &person)
+//
+type Node struct {
+	// Kind defines whether the node is a document, a mapping, a sequence,
+	// a scalar value, or an alias to another node. The specific data type of
+	// scalar nodes may be obtained via the ShortTag and LongTag methods.
+	Kind  Kind
+
+	// Style allows customizing the apperance of the node in the tree.
+	Style Style
+
+	// Tag holds the YAML tag defining the data type for the value.
+	// When decoding, this field will always be set to the resolved tag,
+	// even when it wasn't explicitly provided in the YAML content.
+	// When encoding, if this field is unset the value type will be
+	// implied from the node properties, and if it is set, it will only
+	// be serialized into the representation if TaggedStyle is used or
+	// the implicit tag diverges from the provided one.
+	Tag string
+
+	// Value holds the unescaped and unquoted represenation of the value.
+	Value string
+
+	// Anchor holds the anchor name for this node, which allows aliases to point to it.
+	Anchor string
+
+	// Alias holds the node that this alias points to. Only valid when Kind is AliasNode.
+	Alias *Node
+
+	// Content holds contained nodes for documents, mappings, and sequences.
+	Content []*Node
+
+	// HeadComment holds any comments in the lines preceding the node and
+	// not separated by an empty line.
+	HeadComment string
+
+	// LineComment holds any comments at the end of the line where the node is in.
+	LineComment string
+
+	// FootComment holds any comments following the node and before empty lines.
+	FootComment string
+
+	// Line and Column hold the node position in the decoded YAML text.
+	// These fields are not respected when encoding the node.
+	Line   int
+	Column int
+}
+
+// IsZero returns whether the node has all of its fields unset.
+func (n *Node) IsZero() bool {
+	return n.Kind == 0 && n.Style == 0 && n.Tag == "" && n.Value == "" && n.Anchor == "" && n.Alias == nil && n.Content == nil &&
+		n.HeadComment == "" && n.LineComment == "" && n.FootComment == "" && n.Line == 0 && n.Column == 0
+}
+
+
+// LongTag returns the long form of the tag that indicates the data type for
+// the node. If the Tag field isn't explicitly defined, one will be computed
+// based on the node properties.
+func (n *Node) LongTag() string {
+	return longTag(n.ShortTag())
+}
+
+// ShortTag returns the short form of the YAML tag that indicates data type for
+// the node. If the Tag field isn't explicitly defined, one will be computed
+// based on the node properties.
+func (n *Node) ShortTag() string {
+	if n.indicatedString() {
+		return strTag
+	}
+	if n.Tag == "" || n.Tag == "!" {
+		switch n.Kind {
+		case MappingNode:
+			return mapTag
+		case SequenceNode:
+			return seqTag
+		case AliasNode:
+			if n.Alias != nil {
+				return n.Alias.ShortTag()
+			}
+		case ScalarNode:
+			tag, _ := resolve("", n.Value)
+			return tag
+		case 0:
+			// Special case to make the zero value convenient.
+			if n.IsZero() {
+				return nullTag
+			}
+		}
+		return ""
+	}
+	return shortTag(n.Tag)
+}
+
+func (n *Node) indicatedString() bool {
+	return n.Kind == ScalarNode &&
+		(shortTag(n.Tag) == strTag ||
+			(n.Tag == "" || n.Tag == "!") && n.Style&(SingleQuotedStyle|DoubleQuotedStyle|LiteralStyle|FoldedStyle) != 0)
+}
+
+// SetString is a convenience function that sets the node to a string value
+// and defines its style in a pleasant way depending on its content.
+func (n *Node) SetString(s string) {
+	n.Kind = ScalarNode
+	if utf8.ValidString(s) {
+		n.Value = s
+		n.Tag = strTag
+	} else {
+		n.Value = encodeBase64(s)
+		n.Tag = binaryTag
+	}
+	if strings.Contains(n.Value, "\n") {
+		n.Style = LiteralStyle
+	}
+}
+
+// --------------------------------------------------------------------------
+// Maintain a mapping of keys to structure field indexes
+
+// The code in this section was copied from mgo/bson.
+
+// structInfo holds details for the serialization of fields of
+// a given struct.
+type structInfo struct {
+	FieldsMap  map[string]fieldInfo
+	FieldsList []fieldInfo
+
+	// InlineMap is the number of the field in the struct that
+	// contains an ,inline map, or -1 if there's none.
+	InlineMap int
+
+	// InlineUnmarshalers holds indexes to inlined fields that
+	// contain unmarshaler values.
+	InlineUnmarshalers [][]int
+}
+
+type fieldInfo struct {
+	Key       string
+	Num       int
+	OmitEmpty bool
+	Flow      bool
+	// Id holds the unique field identifier, so we can cheaply
+	// check for field duplicates without maintaining an extra map.
+	Id int
+
+	// Inline holds the field index if the field is part of an inlined struct.
+	Inline []int
+}
+
+var structMap = make(map[reflect.Type]*structInfo)
+var fieldMapMutex sync.RWMutex
+var unmarshalerType reflect.Type
+
+func init() {
+	var v Unmarshaler
+	unmarshalerType = reflect.ValueOf(&v).Elem().Type()
+}
+
+func getStructInfo(st reflect.Type) (*structInfo, error) {
+	fieldMapMutex.RLock()
+	sinfo, found := structMap[st]
+	fieldMapMutex.RUnlock()
+	if found {
+		return sinfo, nil
+	}
+
+	n := st.NumField()
+	fieldsMap := make(map[string]fieldInfo)
+	fieldsList := make([]fieldInfo, 0, n)
+	inlineMap := -1
+	inlineUnmarshalers := [][]int(nil)
+	for i := 0; i != n; i++ {
+		field := st.Field(i)
+		if field.PkgPath != "" && !field.Anonymous {
+			continue // Private field
+		}
+
+		info := fieldInfo{Num: i}
+
+		tag := field.Tag.Get("yaml")
+		if tag == "" && strings.Index(string(field.Tag), ":") < 0 {
+			tag = string(field.Tag)
+		}
+		if tag == "-" {
+			continue
+		}
+
+		inline := false
+		fields := strings.Split(tag, ",")
+		if len(fields) > 1 {
+			for _, flag := range fields[1:] {
+				switch flag {
+				case "omitempty":
+					info.OmitEmpty = true
+				case "flow":
+					info.Flow = true
+				case "inline":
+					inline = true
+				default:
+					return nil, errors.New(fmt.Sprintf("unsupported flag %q in tag %q of type %s", flag, tag, st))
+				}
+			}
+			tag = fields[0]
+		}
+
+		if inline {
+			switch field.Type.Kind() {
+			case reflect.Map:
+				if inlineMap >= 0 {
+					return nil, errors.New("multiple ,inline maps in struct " + st.String())
+				}
+				if field.Type.Key() != reflect.TypeOf("") {
+					return nil, errors.New("option ,inline needs a map with string keys in struct " + st.String())
+				}
+				inlineMap = info.Num
+			case reflect.Struct, reflect.Ptr:
+				ftype := field.Type
+				for ftype.Kind() == reflect.Ptr {
+					ftype = ftype.Elem()
+				}
+				if ftype.Kind() != reflect.Struct {
+					return nil, errors.New("option ,inline may only be used on a struct or map field")
+				}
+				if reflect.PtrTo(ftype).Implements(unmarshalerType) {
+					inlineUnmarshalers = append(inlineUnmarshalers, []int{i})
+				} else {
+					sinfo, err := getStructInfo(ftype)
+					if err != nil {
+						return nil, err
+					}
+					for _, index := range sinfo.InlineUnmarshalers {
+						inlineUnmarshalers = append(inlineUnmarshalers, append([]int{i}, index...))
+					}
+					for _, finfo := range sinfo.FieldsList {
+						if _, found := fieldsMap[finfo.Key]; found {
+							msg := "duplicated key '" + finfo.Key + "' in struct " + st.String()
+							return nil, errors.New(msg)
+						}
+						if finfo.Inline == nil {
+							finfo.Inline = []int{i, finfo.Num}
+						} else {
+							finfo.Inline = append([]int{i}, finfo.Inline...)
+						}
+						finfo.Id = len(fieldsList)
+						fieldsMap[finfo.Key] = finfo
+						fieldsList = append(fieldsList, finfo)
+					}
+				}
+			default:
+				return nil, errors.New("option ,inline may only be used on a struct or map field")
+			}
+			continue
+		}
+
+		if tag != "" {
+			info.Key = tag
+		} else {
+			info.Key = strings.ToLower(field.Name)
+		}
+
+		if _, found = fieldsMap[info.Key]; found {
+			msg := "duplicated key '" + info.Key + "' in struct " + st.String()
+			return nil, errors.New(msg)
+		}
+
+		info.Id = len(fieldsList)
+		fieldsList = append(fieldsList, info)
+		fieldsMap[info.Key] = info
+	}
+
+	sinfo = &structInfo{
+		FieldsMap:          fieldsMap,
+		FieldsList:         fieldsList,
+		InlineMap:          inlineMap,
+		InlineUnmarshalers: inlineUnmarshalers,
+	}
+
+	fieldMapMutex.Lock()
+	structMap[st] = sinfo
+	fieldMapMutex.Unlock()
+	return sinfo, nil
+}
+
+// IsZeroer is used to check whether an object is zero to
+// determine whether it should be omitted when marshaling
+// with the omitempty flag. One notable implementation
+// is time.Time.
+type IsZeroer interface {
+	IsZero() bool
+}
+
+func isZero(v reflect.Value) bool {
+	kind := v.Kind()
+	if z, ok := v.Interface().(IsZeroer); ok {
+		if (kind == reflect.Ptr || kind == reflect.Interface) && v.IsNil() {
+			return true
+		}
+		return z.IsZero()
+	}
+	switch kind {
+	case reflect.String:
+		return len(v.String()) == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	case reflect.Slice:
+		return v.Len() == 0
+	case reflect.Map:
+		return v.Len() == 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Struct:
+		vt := v.Type()
+		for i := v.NumField() - 1; i >= 0; i-- {
+			if vt.Field(i).PkgPath != "" {
+				continue // Private field
+			}
+			if !isZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}

vendor/gopkg.in/yaml.v3/yamlh.go

@@ -0,0 +1,807 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"fmt"
+	"io"
+)
+
+// The version directive data.
+type yaml_version_directive_t struct {
+	major int8 // The major version number.
+	minor int8 // The minor version number.
+}
+
+// The tag directive data.
+type yaml_tag_directive_t struct {
+	handle []byte // The tag handle.
+	prefix []byte // The tag prefix.
+}
+
+type yaml_encoding_t int
+
+// The stream encoding.
+const (
+	// Let the parser choose the encoding.
+	yaml_ANY_ENCODING yaml_encoding_t = iota
+
+	yaml_UTF8_ENCODING    // The default UTF-8 encoding.
+	yaml_UTF16LE_ENCODING // The UTF-16-LE encoding with BOM.
+	yaml_UTF16BE_ENCODING // The UTF-16-BE encoding with BOM.
+)
+
+type yaml_break_t int
+
+// Line break types.
+const (
+	// Let the parser choose the break type.
+	yaml_ANY_BREAK yaml_break_t = iota
+
+	yaml_CR_BREAK   // Use CR for line breaks (Mac style).
+	yaml_LN_BREAK   // Use LN for line breaks (Unix style).
+	yaml_CRLN_BREAK // Use CR LN for line breaks (DOS style).
+)
+
+type yaml_error_type_t int
+
+// Many bad things could happen with the parser and emitter.
+const (
+	// No error is produced.
+	yaml_NO_ERROR yaml_error_type_t = iota
+
+	yaml_MEMORY_ERROR   // Cannot allocate or reallocate a block of memory.
+	yaml_READER_ERROR   // Cannot read or decode the input stream.
+	yaml_SCANNER_ERROR  // Cannot scan the input stream.
+	yaml_PARSER_ERROR   // Cannot parse the input stream.
+	yaml_COMPOSER_ERROR // Cannot compose a YAML document.
+	yaml_WRITER_ERROR   // Cannot write to the output stream.
+	yaml_EMITTER_ERROR  // Cannot emit a YAML stream.
+)
+
+// The pointer position.
+type yaml_mark_t struct {
+	index  int // The position index.
+	line   int // The position line.
+	column int // The position column.
+}
+
+// Node Styles
+
+type yaml_style_t int8
+
+type yaml_scalar_style_t yaml_style_t
+
+// Scalar styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SCALAR_STYLE yaml_scalar_style_t = 0
+
+	yaml_PLAIN_SCALAR_STYLE         yaml_scalar_style_t = 1 << iota // The plain scalar style.
+	yaml_SINGLE_QUOTED_SCALAR_STYLE                                 // The single-quoted scalar style.
+	yaml_DOUBLE_QUOTED_SCALAR_STYLE                                 // The double-quoted scalar style.
+	yaml_LITERAL_SCALAR_STYLE                                       // The literal scalar style.
+	yaml_FOLDED_SCALAR_STYLE                                        // The folded scalar style.
+)
+
+type yaml_sequence_style_t yaml_style_t
+
+// Sequence styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SEQUENCE_STYLE yaml_sequence_style_t = iota
+
+	yaml_BLOCK_SEQUENCE_STYLE // The block sequence style.
+	yaml_FLOW_SEQUENCE_STYLE  // The flow sequence style.
+)
+
+type yaml_mapping_style_t yaml_style_t
+
+// Mapping styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_MAPPING_STYLE yaml_mapping_style_t = iota
+
+	yaml_BLOCK_MAPPING_STYLE // The block mapping style.
+	yaml_FLOW_MAPPING_STYLE  // The flow mapping style.
+)
+
+// Tokens
+
+type yaml_token_type_t int
+
+// Token types.
+const (
+	// An empty token.
+	yaml_NO_TOKEN yaml_token_type_t = iota
+
+	yaml_STREAM_START_TOKEN // A STREAM-START token.
+	yaml_STREAM_END_TOKEN   // A STREAM-END token.
+
+	yaml_VERSION_DIRECTIVE_TOKEN // A VERSION-DIRECTIVE token.
+	yaml_TAG_DIRECTIVE_TOKEN     // A TAG-DIRECTIVE token.
+	yaml_DOCUMENT_START_TOKEN    // A DOCUMENT-START token.
+	yaml_DOCUMENT_END_TOKEN      // A DOCUMENT-END token.
+
+	yaml_BLOCK_SEQUENCE_START_TOKEN // A BLOCK-SEQUENCE-START token.
+	yaml_BLOCK_MAPPING_START_TOKEN  // A BLOCK-SEQUENCE-END token.
+	yaml_BLOCK_END_TOKEN            // A BLOCK-END token.
+
+	yaml_FLOW_SEQUENCE_START_TOKEN // A FLOW-SEQUENCE-START token.
+	yaml_FLOW_SEQUENCE_END_TOKEN   // A FLOW-SEQUENCE-END token.
+	yaml_FLOW_MAPPING_START_TOKEN  // A FLOW-MAPPING-START token.
+	yaml_FLOW_MAPPING_END_TOKEN    // A FLOW-MAPPING-END token.
+
+	yaml_BLOCK_ENTRY_TOKEN // A BLOCK-ENTRY token.
+	yaml_FLOW_ENTRY_TOKEN  // A FLOW-ENTRY token.
+	yaml_KEY_TOKEN         // A KEY token.
+	yaml_VALUE_TOKEN       // A VALUE token.
+
+	yaml_ALIAS_TOKEN  // An ALIAS token.
+	yaml_ANCHOR_TOKEN // An ANCHOR token.
+	yaml_TAG_TOKEN    // A TAG token.
+	yaml_SCALAR_TOKEN // A SCALAR token.
+)
+
+func (tt yaml_token_type_t) String() string {
+	switch tt {
+	case yaml_NO_TOKEN:
+		return "yaml_NO_TOKEN"
+	case yaml_STREAM_START_TOKEN:
+		return "yaml_STREAM_START_TOKEN"
+	case yaml_STREAM_END_TOKEN:
+		return "yaml_STREAM_END_TOKEN"
+	case yaml_VERSION_DIRECTIVE_TOKEN:
+		return "yaml_VERSION_DIRECTIVE_TOKEN"
+	case yaml_TAG_DIRECTIVE_TOKEN:
+		return "yaml_TAG_DIRECTIVE_TOKEN"
+	case yaml_DOCUMENT_START_TOKEN:
+		return "yaml_DOCUMENT_START_TOKEN"
+	case yaml_DOCUMENT_END_TOKEN:
+		return "yaml_DOCUMENT_END_TOKEN"
+	case yaml_BLOCK_SEQUENCE_START_TOKEN:
+		return "yaml_BLOCK_SEQUENCE_START_TOKEN"
+	case yaml_BLOCK_MAPPING_START_TOKEN:
+		return "yaml_BLOCK_MAPPING_START_TOKEN"
+	case yaml_BLOCK_END_TOKEN:
+		return "yaml_BLOCK_END_TOKEN"
+	case yaml_FLOW_SEQUENCE_START_TOKEN:
+		return "yaml_FLOW_SEQUENCE_START_TOKEN"
+	case yaml_FLOW_SEQUENCE_END_TOKEN:
+		return "yaml_FLOW_SEQUENCE_END_TOKEN"
+	case yaml_FLOW_MAPPING_START_TOKEN:
+		return "yaml_FLOW_MAPPING_START_TOKEN"
+	case yaml_FLOW_MAPPING_END_TOKEN:
+		return "yaml_FLOW_MAPPING_END_TOKEN"
+	case yaml_BLOCK_ENTRY_TOKEN:
+		return "yaml_BLOCK_ENTRY_TOKEN"
+	case yaml_FLOW_ENTRY_TOKEN:
+		return "yaml_FLOW_ENTRY_TOKEN"
+	case yaml_KEY_TOKEN:
+		return "yaml_KEY_TOKEN"
+	case yaml_VALUE_TOKEN:
+		return "yaml_VALUE_TOKEN"
+	case yaml_ALIAS_TOKEN:
+		return "yaml_ALIAS_TOKEN"
+	case yaml_ANCHOR_TOKEN:
+		return "yaml_ANCHOR_TOKEN"
+	case yaml_TAG_TOKEN:
+		return "yaml_TAG_TOKEN"
+	case yaml_SCALAR_TOKEN:
+		return "yaml_SCALAR_TOKEN"
+	}
+	return "<unknown token>"
+}
+
+// The token structure.
+type yaml_token_t struct {
+	// The token type.
+	typ yaml_token_type_t
+
+	// The start/end of the token.
+	start_mark, end_mark yaml_mark_t
+
+	// The stream encoding (for yaml_STREAM_START_TOKEN).
+	encoding yaml_encoding_t
+
+	// The alias/anchor/scalar value or tag/tag directive handle
+	// (for yaml_ALIAS_TOKEN, yaml_ANCHOR_TOKEN, yaml_SCALAR_TOKEN, yaml_TAG_TOKEN, yaml_TAG_DIRECTIVE_TOKEN).
+	value []byte
+
+	// The tag suffix (for yaml_TAG_TOKEN).
+	suffix []byte
+
+	// The tag directive prefix (for yaml_TAG_DIRECTIVE_TOKEN).
+	prefix []byte
+
+	// The scalar style (for yaml_SCALAR_TOKEN).
+	style yaml_scalar_style_t
+
+	// The version directive major/minor (for yaml_VERSION_DIRECTIVE_TOKEN).
+	major, minor int8
+}
+
+// Events
+
+type yaml_event_type_t int8
+
+// Event types.
+const (
+	// An empty event.
+	yaml_NO_EVENT yaml_event_type_t = iota
+
+	yaml_STREAM_START_EVENT   // A STREAM-START event.
+	yaml_STREAM_END_EVENT     // A STREAM-END event.
+	yaml_DOCUMENT_START_EVENT // A DOCUMENT-START event.
+	yaml_DOCUMENT_END_EVENT   // A DOCUMENT-END event.
+	yaml_ALIAS_EVENT          // An ALIAS event.
+	yaml_SCALAR_EVENT         // A SCALAR event.
+	yaml_SEQUENCE_START_EVENT // A SEQUENCE-START event.
+	yaml_SEQUENCE_END_EVENT   // A SEQUENCE-END event.
+	yaml_MAPPING_START_EVENT  // A MAPPING-START event.
+	yaml_MAPPING_END_EVENT    // A MAPPING-END event.
+	yaml_TAIL_COMMENT_EVENT
+)
+
+var eventStrings = []string{
+	yaml_NO_EVENT:             "none",
+	yaml_STREAM_START_EVENT:   "stream start",
+	yaml_STREAM_END_EVENT:     "stream end",
+	yaml_DOCUMENT_START_EVENT: "document start",
+	yaml_DOCUMENT_END_EVENT:   "document end",
+	yaml_ALIAS_EVENT:          "alias",
+	yaml_SCALAR_EVENT:         "scalar",
+	yaml_SEQUENCE_START_EVENT: "sequence start",
+	yaml_SEQUENCE_END_EVENT:   "sequence end",
+	yaml_MAPPING_START_EVENT:  "mapping start",
+	yaml_MAPPING_END_EVENT:    "mapping end",
+	yaml_TAIL_COMMENT_EVENT:   "tail comment",
+}
+
+func (e yaml_event_type_t) String() string {
+	if e < 0 || int(e) >= len(eventStrings) {
+		return fmt.Sprintf("unknown event %d", e)
+	}
+	return eventStrings[e]
+}
+
+// The event structure.
+type yaml_event_t struct {
+
+	// The event type.
+	typ yaml_event_type_t
+
+	// The start and end of the event.
+	start_mark, end_mark yaml_mark_t
+
+	// The document encoding (for yaml_STREAM_START_EVENT).
+	encoding yaml_encoding_t
+
+	// The version directive (for yaml_DOCUMENT_START_EVENT).
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives (for yaml_DOCUMENT_START_EVENT).
+	tag_directives []yaml_tag_directive_t
+
+	// The comments
+	head_comment []byte
+	line_comment []byte
+	foot_comment []byte
+	tail_comment []byte
+
+	// The anchor (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_ALIAS_EVENT).
+	anchor []byte
+
+	// The tag (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	tag []byte
+
+	// The scalar value (for yaml_SCALAR_EVENT).
+	value []byte
+
+	// Is the document start/end indicator implicit, or the tag optional?
+	// (for yaml_DOCUMENT_START_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_SCALAR_EVENT).
+	implicit bool
+
+	// Is the tag optional for any non-plain style? (for yaml_SCALAR_EVENT).
+	quoted_implicit bool
+
+	// The style (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	style yaml_style_t
+}
+
+func (e *yaml_event_t) scalar_style() yaml_scalar_style_t     { return yaml_scalar_style_t(e.style) }
+func (e *yaml_event_t) sequence_style() yaml_sequence_style_t { return yaml_sequence_style_t(e.style) }
+func (e *yaml_event_t) mapping_style() yaml_mapping_style_t   { return yaml_mapping_style_t(e.style) }
+
+// Nodes
+
+const (
+	yaml_NULL_TAG      = "tag:yaml.org,2002:null"      // The tag !!null with the only possible value: null.
+	yaml_BOOL_TAG      = "tag:yaml.org,2002:bool"      // The tag !!bool with the values: true and false.
+	yaml_STR_TAG       = "tag:yaml.org,2002:str"       // The tag !!str for string values.
+	yaml_INT_TAG       = "tag:yaml.org,2002:int"       // The tag !!int for integer values.
+	yaml_FLOAT_TAG     = "tag:yaml.org,2002:float"     // The tag !!float for float values.
+	yaml_TIMESTAMP_TAG = "tag:yaml.org,2002:timestamp" // The tag !!timestamp for date and time values.
+
+	yaml_SEQ_TAG = "tag:yaml.org,2002:seq" // The tag !!seq is used to denote sequences.
+	yaml_MAP_TAG = "tag:yaml.org,2002:map" // The tag !!map is used to denote mapping.
+
+	// Not in original libyaml.
+	yaml_BINARY_TAG = "tag:yaml.org,2002:binary"
+	yaml_MERGE_TAG  = "tag:yaml.org,2002:merge"
+
+	yaml_DEFAULT_SCALAR_TAG   = yaml_STR_TAG // The default scalar tag is !!str.
+	yaml_DEFAULT_SEQUENCE_TAG = yaml_SEQ_TAG // The default sequence tag is !!seq.
+	yaml_DEFAULT_MAPPING_TAG  = yaml_MAP_TAG // The default mapping tag is !!map.
+)
+
+type yaml_node_type_t int
+
+// Node types.
+const (
+	// An empty node.
+	yaml_NO_NODE yaml_node_type_t = iota
+
+	yaml_SCALAR_NODE   // A scalar node.
+	yaml_SEQUENCE_NODE // A sequence node.
+	yaml_MAPPING_NODE  // A mapping node.
+)
+
+// An element of a sequence node.
+type yaml_node_item_t int
+
+// An element of a mapping node.
+type yaml_node_pair_t struct {
+	key   int // The key of the element.
+	value int // The value of the element.
+}
+
+// The node structure.
+type yaml_node_t struct {
+	typ yaml_node_type_t // The node type.
+	tag []byte           // The node tag.
+
+	// The node data.
+
+	// The scalar parameters (for yaml_SCALAR_NODE).
+	scalar struct {
+		value  []byte              // The scalar value.
+		length int                 // The length of the scalar value.
+		style  yaml_scalar_style_t // The scalar style.
+	}
+
+	// The sequence parameters (for YAML_SEQUENCE_NODE).
+	sequence struct {
+		items_data []yaml_node_item_t    // The stack of sequence items.
+		style      yaml_sequence_style_t // The sequence style.
+	}
+
+	// The mapping parameters (for yaml_MAPPING_NODE).
+	mapping struct {
+		pairs_data  []yaml_node_pair_t   // The stack of mapping pairs (key, value).
+		pairs_start *yaml_node_pair_t    // The beginning of the stack.
+		pairs_end   *yaml_node_pair_t    // The end of the stack.
+		pairs_top   *yaml_node_pair_t    // The top of the stack.
+		style       yaml_mapping_style_t // The mapping style.
+	}
+
+	start_mark yaml_mark_t // The beginning of the node.
+	end_mark   yaml_mark_t // The end of the node.
+
+}
+
+// The document structure.
+type yaml_document_t struct {
+
+	// The document nodes.
+	nodes []yaml_node_t
+
+	// The version directive.
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives.
+	tag_directives_data  []yaml_tag_directive_t
+	tag_directives_start int // The beginning of the tag directives list.
+	tag_directives_end   int // The end of the tag directives list.
+
+	start_implicit int // Is the document start indicator implicit?
+	end_implicit   int // Is the document end indicator implicit?
+
+	// The start/end of the document.
+	start_mark, end_mark yaml_mark_t
+}
+
+// The prototype of a read handler.
+//
+// The read handler is called when the parser needs to read more bytes from the
+// source. The handler should write not more than size bytes to the buffer.
+// The number of written bytes should be set to the size_read variable.
+//
+// [in,out]   data        A pointer to an application data specified by
+//                        yaml_parser_set_input().
+// [out]      buffer      The buffer to write the data from the source.
+// [in]       size        The size of the buffer.
+// [out]      size_read   The actual number of bytes read from the source.
+//
+// On success, the handler should return 1.  If the handler failed,
+// the returned value should be 0. On EOF, the handler should set the
+// size_read to 0 and return 1.
+type yaml_read_handler_t func(parser *yaml_parser_t, buffer []byte) (n int, err error)
+
+// This structure holds information about a potential simple key.
+type yaml_simple_key_t struct {
+	possible     bool        // Is a simple key possible?
+	required     bool        // Is a simple key required?
+	token_number int         // The number of the token.
+	mark         yaml_mark_t // The position mark.
+}
+
+// The states of the parser.
+type yaml_parser_state_t int
+
+const (
+	yaml_PARSE_STREAM_START_STATE yaml_parser_state_t = iota
+
+	yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE           // Expect the beginning of an implicit document.
+	yaml_PARSE_DOCUMENT_START_STATE                    // Expect DOCUMENT-START.
+	yaml_PARSE_DOCUMENT_CONTENT_STATE                  // Expect the content of a document.
+	yaml_PARSE_DOCUMENT_END_STATE                      // Expect DOCUMENT-END.
+	yaml_PARSE_BLOCK_NODE_STATE                        // Expect a block node.
+	yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE // Expect a block node or indentless sequence.
+	yaml_PARSE_FLOW_NODE_STATE                         // Expect a flow node.
+	yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE        // Expect the first entry of a block sequence.
+	yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE              // Expect an entry of a block sequence.
+	yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE         // Expect an entry of an indentless sequence.
+	yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE           // Expect the first key of a block mapping.
+	yaml_PARSE_BLOCK_MAPPING_KEY_STATE                 // Expect a block mapping key.
+	yaml_PARSE_BLOCK_MAPPING_VALUE_STATE               // Expect a block mapping value.
+	yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE         // Expect the first entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE               // Expect an entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE   // Expect a key of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE // Expect a value of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE   // Expect the and of an ordered mapping entry.
+	yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE            // Expect the first key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_KEY_STATE                  // Expect a key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_VALUE_STATE                // Expect a value of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE          // Expect an empty value of a flow mapping.
+	yaml_PARSE_END_STATE                               // Expect nothing.
+)
+
+func (ps yaml_parser_state_t) String() string {
+	switch ps {
+	case yaml_PARSE_STREAM_START_STATE:
+		return "yaml_PARSE_STREAM_START_STATE"
+	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
+		return "yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_START_STATE:
+		return "yaml_PARSE_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
+		return "yaml_PARSE_DOCUMENT_CONTENT_STATE"
+	case yaml_PARSE_DOCUMENT_END_STATE:
+		return "yaml_PARSE_DOCUMENT_END_STATE"
+	case yaml_PARSE_BLOCK_NODE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_STATE"
+	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE"
+	case yaml_PARSE_FLOW_NODE_STATE:
+		return "yaml_PARSE_FLOW_NODE_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE"
+	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE"
+	case yaml_PARSE_END_STATE:
+		return "yaml_PARSE_END_STATE"
+	}
+	return "<unknown parser state>"
+}
+
+// This structure holds aliases data.
+type yaml_alias_data_t struct {
+	anchor []byte      // The anchor.
+	index  int         // The node id.
+	mark   yaml_mark_t // The anchor mark.
+}
+
+// The parser structure.
+//
+// All members are internal. Manage the structure using the
+// yaml_parser_ family of functions.
+type yaml_parser_t struct {
+
+	// Error handling
+
+	error yaml_error_type_t // Error type.
+
+	problem string // Error description.
+
+	// The byte about which the problem occurred.
+	problem_offset int
+	problem_value  int
+	problem_mark   yaml_mark_t
+
+	// The error context.
+	context      string
+	context_mark yaml_mark_t
+
+	// Reader stuff
+
+	read_handler yaml_read_handler_t // Read handler.
+
+	input_reader io.Reader // File input data.
+	input        []byte    // String input data.
+	input_pos    int
+
+	eof bool // EOF flag
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	unread int // The number of unread characters in the buffer.
+
+	newlines int // The number of line breaks since last non-break/non-blank character
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The input encoding.
+
+	offset int         // The offset of the current position (in bytes).
+	mark   yaml_mark_t // The mark of the current position.
+
+	// Comments
+
+	head_comment []byte // The current head comments
+	line_comment []byte // The current line comments
+	foot_comment []byte // The current foot comments
+	tail_comment []byte // Foot comment that happens at the end of a block.
+	stem_comment []byte // Comment in item preceding a nested structure (list inside list item, etc)
+
+	comments      []yaml_comment_t // The folded comments for all parsed tokens
+	comments_head int
+
+	// Scanner stuff
+
+	stream_start_produced bool // Have we started to scan the input stream?
+	stream_end_produced   bool // Have we reached the end of the input stream?
+
+	flow_level int // The number of unclosed '[' and '{' indicators.
+
+	tokens          []yaml_token_t // The tokens queue.
+	tokens_head     int            // The head of the tokens queue.
+	tokens_parsed   int            // The number of tokens fetched from the queue.
+	token_available bool           // Does the tokens queue contain a token ready for dequeueing.
+
+	indent  int   // The current indentation level.
+	indents []int // The indentation levels stack.
+
+	simple_key_allowed bool                // May a simple key occur at the current position?
+	simple_keys        []yaml_simple_key_t // The stack of simple keys.
+	simple_keys_by_tok map[int]int         // possible simple_key indexes indexed by token_number
+
+	// Parser stuff
+
+	state          yaml_parser_state_t    // The current parser state.
+	states         []yaml_parser_state_t  // The parser states stack.
+	marks          []yaml_mark_t          // The stack of marks.
+	tag_directives []yaml_tag_directive_t // The list of TAG directives.
+
+	// Dumper stuff
+
+	aliases []yaml_alias_data_t // The alias data.
+
+	document *yaml_document_t // The currently parsed document.
+}
+
+type yaml_comment_t struct {
+
+	scan_mark  yaml_mark_t // Position where scanning for comments started
+	token_mark yaml_mark_t // Position after which tokens will be associated with this comment
+	start_mark yaml_mark_t // Position of '#' comment mark
+	end_mark   yaml_mark_t // Position where comment terminated
+
+	head []byte
+	line []byte
+	foot []byte
+}
+
+// Emitter Definitions
+
+// The prototype of a write handler.
+//
+// The write handler is called when the emitter needs to flush the accumulated
+// characters to the output.  The handler should write @a size bytes of the
+// @a buffer to the output.
+//
+// @param[in,out]   data        A pointer to an application data specified by
+//                              yaml_emitter_set_output().
+// @param[in]       buffer      The buffer with bytes to be written.
+// @param[in]       size        The size of the buffer.
+//
+// @returns On success, the handler should return @c 1.  If the handler failed,
+// the returned value should be @c 0.
+//
+type yaml_write_handler_t func(emitter *yaml_emitter_t, buffer []byte) error
+
+type yaml_emitter_state_t int
+
+// The emitter states.
+const (
+	// Expect STREAM-START.
+	yaml_EMIT_STREAM_START_STATE yaml_emitter_state_t = iota
+
+	yaml_EMIT_FIRST_DOCUMENT_START_STATE       // Expect the first DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_START_STATE             // Expect DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_CONTENT_STATE           // Expect the content of a document.
+	yaml_EMIT_DOCUMENT_END_STATE               // Expect DOCUMENT-END.
+	yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE   // Expect the first item of a flow sequence.
+	yaml_EMIT_FLOW_SEQUENCE_TRAIL_ITEM_STATE   // Expect the next item of a flow sequence, with the comma already written out
+	yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE         // Expect an item of a flow sequence.
+	yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE     // Expect the first key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_TRAIL_KEY_STATE     // Expect the next key of a flow mapping, with the comma already written out
+	yaml_EMIT_FLOW_MAPPING_KEY_STATE           // Expect a key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE  // Expect a value for a simple key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_VALUE_STATE         // Expect a value of a flow mapping.
+	yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE  // Expect the first item of a block sequence.
+	yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE        // Expect an item of a block sequence.
+	yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE    // Expect the first key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_KEY_STATE          // Expect the key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE // Expect a value for a simple key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_VALUE_STATE        // Expect a value of a block mapping.
+	yaml_EMIT_END_STATE                        // Expect nothing.
+)
+
+// The emitter structure.
+//
+// All members are internal.  Manage the structure using the @c yaml_emitter_
+// family of functions.
+type yaml_emitter_t struct {
+
+	// Error handling
+
+	error   yaml_error_type_t // Error type.
+	problem string            // Error description.
+
+	// Writer stuff
+
+	write_handler yaml_write_handler_t // Write handler.
+
+	output_buffer *[]byte   // String output data.
+	output_writer io.Writer // File output data.
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The stream encoding.
+
+	// Emitter stuff
+
+	canonical   bool         // If the output is in the canonical style?
+	best_indent int          // The number of indentation spaces.
+	best_width  int          // The preferred width of the output lines.
+	unicode     bool         // Allow unescaped non-ASCII characters?
+	line_break  yaml_break_t // The preferred line break.
+
+	state  yaml_emitter_state_t   // The current emitter state.
+	states []yaml_emitter_state_t // The stack of states.
+
+	events      []yaml_event_t // The event queue.
+	events_head int            // The head of the event queue.
+
+	indents []int // The stack of indentation levels.
+
+	tag_directives []yaml_tag_directive_t // The list of tag directives.
+
+	indent int // The current indentation level.
+
+	flow_level int // The current flow level.
+
+	root_context       bool // Is it the document root context?
+	sequence_context   bool // Is it a sequence context?
+	mapping_context    bool // Is it a mapping context?
+	simple_key_context bool // Is it a simple mapping key context?
+
+	line       int  // The current line.
+	column     int  // The current column.
+	whitespace bool // If the last character was a whitespace?
+	indention  bool // If the last character was an indentation character (' ', '-', '?', ':')?
+	open_ended bool // If an explicit document end is required?
+
+	space_above bool // Is there's an empty line above?
+	foot_indent int  // The indent used to write the foot comment above, or -1 if none.
+
+	// Anchor analysis.
+	anchor_data struct {
+		anchor []byte // The anchor value.
+		alias  bool   // Is it an alias?
+	}
+
+	// Tag analysis.
+	tag_data struct {
+		handle []byte // The tag handle.
+		suffix []byte // The tag suffix.
+	}
+
+	// Scalar analysis.
+	scalar_data struct {
+		value                 []byte              // The scalar value.
+		multiline             bool                // Does the scalar contain line breaks?
+		flow_plain_allowed    bool                // Can the scalar be expessed in the flow plain style?
+		block_plain_allowed   bool                // Can the scalar be expressed in the block plain style?
+		single_quoted_allowed bool                // Can the scalar be expressed in the single quoted style?
+		block_allowed         bool                // Can the scalar be expressed in the literal or folded styles?
+		style                 yaml_scalar_style_t // The output style.
+	}
+
+	// Comments
+	head_comment []byte
+	line_comment []byte
+	foot_comment []byte
+	tail_comment []byte
+
+	key_line_comment []byte
+
+	// Dumper stuff
+
+	opened bool // If the stream was already opened?
+	closed bool // If the stream was already closed?
+
+	// The information associated with the document nodes.
+	anchors *struct {
+		references int  // The number of references.
+		anchor     int  // The anchor id.
+		serialized bool // If the node has been emitted?
+	}
+
+	last_anchor_id int // The last assigned anchor id.
+
+	document *yaml_document_t // The currently emitted document.
+}

vendor/gopkg.in/yaml.v3/yamlprivateh.go

@@ -0,0 +1,198 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+const (
+	// The size of the input raw buffer.
+	input_raw_buffer_size = 512
+
+	// The size of the input buffer.
+	// It should be possible to decode the whole raw buffer.
+	input_buffer_size = input_raw_buffer_size * 3
+
+	// The size of the output buffer.
+	output_buffer_size = 128
+
+	// The size of the output raw buffer.
+	// It should be possible to encode the whole output buffer.
+	output_raw_buffer_size = (output_buffer_size*2 + 2)
+
+	// The size of other stacks and queues.
+	initial_stack_size  = 16
+	initial_queue_size  = 16
+	initial_string_size = 16
+)
+
+// Check if the character at the specified position is an alphabetical
+// character, a digit, '_', or '-'.
+func is_alpha(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'Z' || b[i] >= 'a' && b[i] <= 'z' || b[i] == '_' || b[i] == '-'
+}
+
+// Check if the character at the specified position is a digit.
+func is_digit(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9'
+}
+
+// Get the value of a digit.
+func as_digit(b []byte, i int) int {
+	return int(b[i]) - '0'
+}
+
+// Check if the character at the specified position is a hex-digit.
+func is_hex(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'F' || b[i] >= 'a' && b[i] <= 'f'
+}
+
+// Get the value of a hex-digit.
+func as_hex(b []byte, i int) int {
+	bi := b[i]
+	if bi >= 'A' && bi <= 'F' {
+		return int(bi) - 'A' + 10
+	}
+	if bi >= 'a' && bi <= 'f' {
+		return int(bi) - 'a' + 10
+	}
+	return int(bi) - '0'
+}
+
+// Check if the character is ASCII.
+func is_ascii(b []byte, i int) bool {
+	return b[i] <= 0x7F
+}
+
+// Check if the character at the start of the buffer can be printed unescaped.
+func is_printable(b []byte, i int) bool {
+	return ((b[i] == 0x0A) || // . == #x0A
+		(b[i] >= 0x20 && b[i] <= 0x7E) || // #x20 <= . <= #x7E
+		(b[i] == 0xC2 && b[i+1] >= 0xA0) || // #0xA0 <= . <= #xD7FF
+		(b[i] > 0xC2 && b[i] < 0xED) ||
+		(b[i] == 0xED && b[i+1] < 0xA0) ||
+		(b[i] == 0xEE) ||
+		(b[i] == 0xEF && // #xE000 <= . <= #xFFFD
+			!(b[i+1] == 0xBB && b[i+2] == 0xBF) && // && . != #xFEFF
+			!(b[i+1] == 0xBF && (b[i+2] == 0xBE || b[i+2] == 0xBF))))
+}
+
+// Check if the character at the specified position is NUL.
+func is_z(b []byte, i int) bool {
+	return b[i] == 0x00
+}
+
+// Check if the beginning of the buffer is a BOM.
+func is_bom(b []byte, i int) bool {
+	return b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF
+}
+
+// Check if the character at the specified position is space.
+func is_space(b []byte, i int) bool {
+	return b[i] == ' '
+}
+
+// Check if the character at the specified position is tab.
+func is_tab(b []byte, i int) bool {
+	return b[i] == '\t'
+}
+
+// Check if the character at the specified position is blank (space or tab).
+func is_blank(b []byte, i int) bool {
+	//return is_space(b, i) || is_tab(b, i)
+	return b[i] == ' ' || b[i] == '\t'
+}
+
+// Check if the character at the specified position is a line break.
+func is_break(b []byte, i int) bool {
+	return (b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9) // PS (#x2029)
+}
+
+func is_crlf(b []byte, i int) bool {
+	return b[i] == '\r' && b[i+1] == '\n'
+}
+
+// Check if the character is a line break or NUL.
+func is_breakz(b []byte, i int) bool {
+	//return is_break(b, i) || is_z(b, i)
+	return (
+		// is_break:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		// is_z:
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, or NUL.
+func is_spacez(b []byte, i int) bool {
+	//return is_space(b, i) || is_breakz(b, i)
+	return (
+		// is_space:
+		b[i] == ' ' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, tab, or NUL.
+func is_blankz(b []byte, i int) bool {
+	//return is_blank(b, i) || is_breakz(b, i)
+	return (
+		// is_blank:
+		b[i] == ' ' || b[i] == '\t' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Determine the width of the character.
+func width(b byte) int {
+	// Don't replace these by a switch without first
+	// confirming that it is being inlined.
+	if b&0x80 == 0x00 {
+		return 1
+	}
+	if b&0xE0 == 0xC0 {
+		return 2
+	}
+	if b&0xF0 == 0xE0 {
+		return 3
+	}
+	if b&0xF8 == 0xF0 {
+		return 4
+	}
+	return 0
+
+}