open-nomad/vendor/gopkg.in/yaml.v2/encode.go
Seth Hoenig 435c0d9fc8 deps: Switch to Go modules for dependency management
This PR switches the Nomad repository from using govendor to Go modules
for managing dependencies. Aspects of the Nomad workflow remain pretty
much the same. The usual Makefile targets should continue to work as
they always did. The API submodule simply defers to the parent Nomad
version on the repository, keeping the semantics of API versioning that
currently exists.
2020-06-02 14:30:36 -05:00

391 lines
9.6 KiB
Go

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()
}