GoToSocial/vendor/github.com/pelletier/go-toml/v2/marshaler.go

1043 lines
22 KiB
Go

package toml
import (
"bytes"
"encoding"
"fmt"
"io"
"math"
"reflect"
"sort"
"strconv"
"strings"
"time"
"unicode"
"github.com/pelletier/go-toml/v2/internal/characters"
)
// Marshal serializes a Go value as a TOML document.
//
// It is a shortcut for Encoder.Encode() with the default options.
func Marshal(v interface{}) ([]byte, error) {
var buf bytes.Buffer
enc := NewEncoder(&buf)
err := enc.Encode(v)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// Encoder writes a TOML document to an output stream.
type Encoder struct {
// output
w io.Writer
// global settings
tablesInline bool
arraysMultiline bool
indentSymbol string
indentTables bool
}
// NewEncoder returns a new Encoder that writes to w.
func NewEncoder(w io.Writer) *Encoder {
return &Encoder{
w: w,
indentSymbol: " ",
}
}
// SetTablesInline forces the encoder to emit all tables inline.
//
// This behavior can be controlled on an individual struct field basis with the
// inline tag:
//
// MyField `toml:",inline"`
func (enc *Encoder) SetTablesInline(inline bool) *Encoder {
enc.tablesInline = inline
return enc
}
// SetArraysMultiline forces the encoder to emit all arrays with one element per
// line.
//
// This behavior can be controlled on an individual struct field basis with the multiline tag:
//
// MyField `multiline:"true"`
func (enc *Encoder) SetArraysMultiline(multiline bool) *Encoder {
enc.arraysMultiline = multiline
return enc
}
// SetIndentSymbol defines the string that should be used for indentation. The
// provided string is repeated for each indentation level. Defaults to two
// spaces.
func (enc *Encoder) SetIndentSymbol(s string) *Encoder {
enc.indentSymbol = s
return enc
}
// SetIndentTables forces the encoder to intent tables and array tables.
func (enc *Encoder) SetIndentTables(indent bool) *Encoder {
enc.indentTables = indent
return enc
}
// Encode writes a TOML representation of v to the stream.
//
// If v cannot be represented to TOML it returns an error.
//
// # Encoding rules
//
// A top level slice containing only maps or structs is encoded as [[table
// array]].
//
// All slices not matching rule 1 are encoded as [array]. As a result, any map
// or struct they contain is encoded as an {inline table}.
//
// Nil interfaces and nil pointers are not supported.
//
// Keys in key-values always have one part.
//
// Intermediate tables are always printed.
//
// By default, strings are encoded as literal string, unless they contain either
// a newline character or a single quote. In that case they are emitted as
// quoted strings.
//
// Unsigned integers larger than math.MaxInt64 cannot be encoded. Doing so
// results in an error. This rule exists because the TOML specification only
// requires parsers to support at least the 64 bits integer range. Allowing
// larger numbers would create non-standard TOML documents, which may not be
// readable (at best) by other implementations. To encode such numbers, a
// solution is a custom type that implements encoding.TextMarshaler.
//
// When encoding structs, fields are encoded in order of definition, with their
// exact name.
//
// Tables and array tables are separated by empty lines. However, consecutive
// subtables definitions are not. For example:
//
// [top1]
//
// [top2]
// [top2.child1]
//
// [[array]]
//
// [[array]]
// [array.child2]
//
// # Struct tags
//
// The encoding of each public struct field can be customized by the format
// string in the "toml" key of the struct field's tag. This follows
// encoding/json's convention. The format string starts with the name of the
// field, optionally followed by a comma-separated list of options. The name may
// be empty in order to provide options without overriding the default name.
//
// The "multiline" option emits strings as quoted multi-line TOML strings. It
// has no effect on fields that would not be encoded as strings.
//
// The "inline" option turns fields that would be emitted as tables into inline
// tables instead. It has no effect on other fields.
//
// The "omitempty" option prevents empty values or groups from being emitted.
//
// In addition to the "toml" tag struct tag, a "comment" tag can be used to emit
// a TOML comment before the value being annotated. Comments are ignored inside
// inline tables. For array tables, the comment is only present before the first
// element of the array.
func (enc *Encoder) Encode(v interface{}) error {
var (
b []byte
ctx encoderCtx
)
ctx.inline = enc.tablesInline
if v == nil {
return fmt.Errorf("toml: cannot encode a nil interface")
}
b, err := enc.encode(b, ctx, reflect.ValueOf(v))
if err != nil {
return err
}
_, err = enc.w.Write(b)
if err != nil {
return fmt.Errorf("toml: cannot write: %w", err)
}
return nil
}
type valueOptions struct {
multiline bool
omitempty bool
comment string
}
type encoderCtx struct {
// Current top-level key.
parentKey []string
// Key that should be used for a KV.
key string
// Extra flag to account for the empty string
hasKey bool
// Set to true to indicate that the encoder is inside a KV, so that all
// tables need to be inlined.
insideKv bool
// Set to true to skip the first table header in an array table.
skipTableHeader bool
// Should the next table be encoded as inline
inline bool
// Indentation level
indent int
// Options coming from struct tags
options valueOptions
}
func (ctx *encoderCtx) shiftKey() {
if ctx.hasKey {
ctx.parentKey = append(ctx.parentKey, ctx.key)
ctx.clearKey()
}
}
func (ctx *encoderCtx) setKey(k string) {
ctx.key = k
ctx.hasKey = true
}
func (ctx *encoderCtx) clearKey() {
ctx.key = ""
ctx.hasKey = false
}
func (ctx *encoderCtx) isRoot() bool {
return len(ctx.parentKey) == 0 && !ctx.hasKey
}
func (enc *Encoder) encode(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
i := v.Interface()
switch x := i.(type) {
case time.Time:
if x.Nanosecond() > 0 {
return x.AppendFormat(b, time.RFC3339Nano), nil
}
return x.AppendFormat(b, time.RFC3339), nil
case LocalTime:
return append(b, x.String()...), nil
case LocalDate:
return append(b, x.String()...), nil
case LocalDateTime:
return append(b, x.String()...), nil
}
hasTextMarshaler := v.Type().Implements(textMarshalerType)
if hasTextMarshaler || (v.CanAddr() && reflect.PtrTo(v.Type()).Implements(textMarshalerType)) {
if !hasTextMarshaler {
v = v.Addr()
}
if ctx.isRoot() {
return nil, fmt.Errorf("toml: type %s implementing the TextMarshaler interface cannot be a root element", v.Type())
}
text, err := v.Interface().(encoding.TextMarshaler).MarshalText()
if err != nil {
return nil, err
}
b = enc.encodeString(b, string(text), ctx.options)
return b, nil
}
switch v.Kind() {
// containers
case reflect.Map:
return enc.encodeMap(b, ctx, v)
case reflect.Struct:
return enc.encodeStruct(b, ctx, v)
case reflect.Slice:
return enc.encodeSlice(b, ctx, v)
case reflect.Interface:
if v.IsNil() {
return nil, fmt.Errorf("toml: encoding a nil interface is not supported")
}
return enc.encode(b, ctx, v.Elem())
case reflect.Ptr:
if v.IsNil() {
return enc.encode(b, ctx, reflect.Zero(v.Type().Elem()))
}
return enc.encode(b, ctx, v.Elem())
// values
case reflect.String:
b = enc.encodeString(b, v.String(), ctx.options)
case reflect.Float32:
f := v.Float()
if math.IsNaN(f) {
b = append(b, "nan"...)
} else if f > math.MaxFloat32 {
b = append(b, "inf"...)
} else if f < -math.MaxFloat32 {
b = append(b, "-inf"...)
} else if math.Trunc(f) == f {
b = strconv.AppendFloat(b, f, 'f', 1, 32)
} else {
b = strconv.AppendFloat(b, f, 'f', -1, 32)
}
case reflect.Float64:
f := v.Float()
if math.IsNaN(f) {
b = append(b, "nan"...)
} else if f > math.MaxFloat64 {
b = append(b, "inf"...)
} else if f < -math.MaxFloat64 {
b = append(b, "-inf"...)
} else if math.Trunc(f) == f {
b = strconv.AppendFloat(b, f, 'f', 1, 64)
} else {
b = strconv.AppendFloat(b, f, 'f', -1, 64)
}
case reflect.Bool:
if v.Bool() {
b = append(b, "true"...)
} else {
b = append(b, "false"...)
}
case reflect.Uint64, reflect.Uint32, reflect.Uint16, reflect.Uint8, reflect.Uint:
x := v.Uint()
if x > uint64(math.MaxInt64) {
return nil, fmt.Errorf("toml: not encoding uint (%d) greater than max int64 (%d)", x, int64(math.MaxInt64))
}
b = strconv.AppendUint(b, x, 10)
case reflect.Int64, reflect.Int32, reflect.Int16, reflect.Int8, reflect.Int:
b = strconv.AppendInt(b, v.Int(), 10)
default:
return nil, fmt.Errorf("toml: cannot encode value of type %s", v.Kind())
}
return b, nil
}
func isNil(v reflect.Value) bool {
switch v.Kind() {
case reflect.Ptr, reflect.Interface, reflect.Map:
return v.IsNil()
default:
return false
}
}
func shouldOmitEmpty(options valueOptions, v reflect.Value) bool {
return options.omitempty && isEmptyValue(v)
}
func (enc *Encoder) encodeKv(b []byte, ctx encoderCtx, options valueOptions, v reflect.Value) ([]byte, error) {
var err error
if !ctx.inline {
b = enc.encodeComment(ctx.indent, options.comment, b)
}
b = enc.indent(ctx.indent, b)
b = enc.encodeKey(b, ctx.key)
b = append(b, " = "...)
// create a copy of the context because the value of a KV shouldn't
// modify the global context.
subctx := ctx
subctx.insideKv = true
subctx.shiftKey()
subctx.options = options
b, err = enc.encode(b, subctx, v)
if err != nil {
return nil, err
}
return b, nil
}
func isEmptyValue(v reflect.Value) bool {
switch v.Kind() {
case reflect.Struct:
return isEmptyStruct(v)
case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
return v.Len() == 0
case reflect.Bool:
return !v.Bool()
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return v.Int() == 0
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
return v.Uint() == 0
case reflect.Float32, reflect.Float64:
return v.Float() == 0
case reflect.Interface, reflect.Ptr:
return v.IsNil()
}
return false
}
func isEmptyStruct(v reflect.Value) bool {
// TODO: merge with walkStruct and cache.
typ := v.Type()
for i := 0; i < typ.NumField(); i++ {
fieldType := typ.Field(i)
// only consider exported fields
if fieldType.PkgPath != "" {
continue
}
tag := fieldType.Tag.Get("toml")
// special field name to skip field
if tag == "-" {
continue
}
f := v.Field(i)
if !isEmptyValue(f) {
return false
}
}
return true
}
const literalQuote = '\''
func (enc *Encoder) encodeString(b []byte, v string, options valueOptions) []byte {
if needsQuoting(v) {
return enc.encodeQuotedString(options.multiline, b, v)
}
return enc.encodeLiteralString(b, v)
}
func needsQuoting(v string) bool {
// TODO: vectorize
for _, b := range []byte(v) {
if b == '\'' || b == '\r' || b == '\n' || characters.InvalidAscii(b) {
return true
}
}
return false
}
// caller should have checked that the string does not contain new lines or ' .
func (enc *Encoder) encodeLiteralString(b []byte, v string) []byte {
b = append(b, literalQuote)
b = append(b, v...)
b = append(b, literalQuote)
return b
}
func (enc *Encoder) encodeQuotedString(multiline bool, b []byte, v string) []byte {
stringQuote := `"`
if multiline {
stringQuote = `"""`
}
b = append(b, stringQuote...)
if multiline {
b = append(b, '\n')
}
const (
hextable = "0123456789ABCDEF"
// U+0000 to U+0008, U+000A to U+001F, U+007F
nul = 0x0
bs = 0x8
lf = 0xa
us = 0x1f
del = 0x7f
)
for _, r := range []byte(v) {
switch r {
case '\\':
b = append(b, `\\`...)
case '"':
b = append(b, `\"`...)
case '\b':
b = append(b, `\b`...)
case '\f':
b = append(b, `\f`...)
case '\n':
if multiline {
b = append(b, r)
} else {
b = append(b, `\n`...)
}
case '\r':
b = append(b, `\r`...)
case '\t':
b = append(b, `\t`...)
default:
switch {
case r >= nul && r <= bs, r >= lf && r <= us, r == del:
b = append(b, `\u00`...)
b = append(b, hextable[r>>4])
b = append(b, hextable[r&0x0f])
default:
b = append(b, r)
}
}
}
b = append(b, stringQuote...)
return b
}
// caller should have checked that the string is in A-Z / a-z / 0-9 / - / _ .
func (enc *Encoder) encodeUnquotedKey(b []byte, v string) []byte {
return append(b, v...)
}
func (enc *Encoder) encodeTableHeader(ctx encoderCtx, b []byte) ([]byte, error) {
if len(ctx.parentKey) == 0 {
return b, nil
}
b = enc.encodeComment(ctx.indent, ctx.options.comment, b)
b = enc.indent(ctx.indent, b)
b = append(b, '[')
b = enc.encodeKey(b, ctx.parentKey[0])
for _, k := range ctx.parentKey[1:] {
b = append(b, '.')
b = enc.encodeKey(b, k)
}
b = append(b, "]\n"...)
return b, nil
}
//nolint:cyclop
func (enc *Encoder) encodeKey(b []byte, k string) []byte {
needsQuotation := false
cannotUseLiteral := false
if len(k) == 0 {
return append(b, "''"...)
}
for _, c := range k {
if (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '-' || c == '_' {
continue
}
if c == literalQuote {
cannotUseLiteral = true
}
needsQuotation = true
}
if needsQuotation && needsQuoting(k) {
cannotUseLiteral = true
}
switch {
case cannotUseLiteral:
return enc.encodeQuotedString(false, b, k)
case needsQuotation:
return enc.encodeLiteralString(b, k)
default:
return enc.encodeUnquotedKey(b, k)
}
}
func (enc *Encoder) encodeMap(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
if v.Type().Key().Kind() != reflect.String {
return nil, fmt.Errorf("toml: type %s is not supported as a map key", v.Type().Key().Kind())
}
var (
t table
emptyValueOptions valueOptions
)
iter := v.MapRange()
for iter.Next() {
k := iter.Key().String()
v := iter.Value()
if isNil(v) {
continue
}
if willConvertToTableOrArrayTable(ctx, v) {
t.pushTable(k, v, emptyValueOptions)
} else {
t.pushKV(k, v, emptyValueOptions)
}
}
sortEntriesByKey(t.kvs)
sortEntriesByKey(t.tables)
return enc.encodeTable(b, ctx, t)
}
func sortEntriesByKey(e []entry) {
sort.Slice(e, func(i, j int) bool {
return e[i].Key < e[j].Key
})
}
type entry struct {
Key string
Value reflect.Value
Options valueOptions
}
type table struct {
kvs []entry
tables []entry
}
func (t *table) pushKV(k string, v reflect.Value, options valueOptions) {
for _, e := range t.kvs {
if e.Key == k {
return
}
}
t.kvs = append(t.kvs, entry{Key: k, Value: v, Options: options})
}
func (t *table) pushTable(k string, v reflect.Value, options valueOptions) {
for _, e := range t.tables {
if e.Key == k {
return
}
}
t.tables = append(t.tables, entry{Key: k, Value: v, Options: options})
}
func walkStruct(ctx encoderCtx, t *table, v reflect.Value) {
// TODO: cache this
typ := v.Type()
for i := 0; i < typ.NumField(); i++ {
fieldType := typ.Field(i)
// only consider exported fields
if fieldType.PkgPath != "" {
continue
}
tag := fieldType.Tag.Get("toml")
// special field name to skip field
if tag == "-" {
continue
}
k, opts := parseTag(tag)
if !isValidName(k) {
k = ""
}
f := v.Field(i)
if k == "" {
if fieldType.Anonymous {
if fieldType.Type.Kind() == reflect.Struct {
walkStruct(ctx, t, f)
}
continue
} else {
k = fieldType.Name
}
}
if isNil(f) {
continue
}
options := valueOptions{
multiline: opts.multiline,
omitempty: opts.omitempty,
comment: fieldType.Tag.Get("comment"),
}
if opts.inline || !willConvertToTableOrArrayTable(ctx, f) {
t.pushKV(k, f, options)
} else {
t.pushTable(k, f, options)
}
}
}
func (enc *Encoder) encodeStruct(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
var t table
walkStruct(ctx, &t, v)
return enc.encodeTable(b, ctx, t)
}
func (enc *Encoder) encodeComment(indent int, comment string, b []byte) []byte {
for len(comment) > 0 {
var line string
idx := strings.IndexByte(comment, '\n')
if idx >= 0 {
line = comment[:idx]
comment = comment[idx+1:]
} else {
line = comment
comment = ""
}
b = enc.indent(indent, b)
b = append(b, "# "...)
b = append(b, line...)
b = append(b, '\n')
}
return b
}
func isValidName(s string) bool {
if s == "" {
return false
}
for _, c := range s {
switch {
case strings.ContainsRune("!#$%&()*+-./:;<=>?@[]^_{|}~ ", c):
// Backslash and quote chars are reserved, but
// otherwise any punctuation chars are allowed
// in a tag name.
case !unicode.IsLetter(c) && !unicode.IsDigit(c):
return false
}
}
return true
}
type tagOptions struct {
multiline bool
inline bool
omitempty bool
}
func parseTag(tag string) (string, tagOptions) {
opts := tagOptions{}
idx := strings.Index(tag, ",")
if idx == -1 {
return tag, opts
}
raw := tag[idx+1:]
tag = string(tag[:idx])
for raw != "" {
var o string
i := strings.Index(raw, ",")
if i >= 0 {
o, raw = raw[:i], raw[i+1:]
} else {
o, raw = raw, ""
}
switch o {
case "multiline":
opts.multiline = true
case "inline":
opts.inline = true
case "omitempty":
opts.omitempty = true
}
}
return tag, opts
}
func (enc *Encoder) encodeTable(b []byte, ctx encoderCtx, t table) ([]byte, error) {
var err error
ctx.shiftKey()
if ctx.insideKv || (ctx.inline && !ctx.isRoot()) {
return enc.encodeTableInline(b, ctx, t)
}
if !ctx.skipTableHeader {
b, err = enc.encodeTableHeader(ctx, b)
if err != nil {
return nil, err
}
if enc.indentTables && len(ctx.parentKey) > 0 {
ctx.indent++
}
}
ctx.skipTableHeader = false
hasNonEmptyKV := false
for _, kv := range t.kvs {
if shouldOmitEmpty(kv.Options, kv.Value) {
continue
}
hasNonEmptyKV = true
ctx.setKey(kv.Key)
b, err = enc.encodeKv(b, ctx, kv.Options, kv.Value)
if err != nil {
return nil, err
}
b = append(b, '\n')
}
first := true
for _, table := range t.tables {
if shouldOmitEmpty(table.Options, table.Value) {
continue
}
if first {
first = false
if hasNonEmptyKV {
b = append(b, '\n')
}
} else {
b = append(b, "\n"...)
}
ctx.setKey(table.Key)
ctx.options = table.Options
b, err = enc.encode(b, ctx, table.Value)
if err != nil {
return nil, err
}
}
return b, nil
}
func (enc *Encoder) encodeTableInline(b []byte, ctx encoderCtx, t table) ([]byte, error) {
var err error
b = append(b, '{')
first := true
for _, kv := range t.kvs {
if shouldOmitEmpty(kv.Options, kv.Value) {
continue
}
if first {
first = false
} else {
b = append(b, `, `...)
}
ctx.setKey(kv.Key)
b, err = enc.encodeKv(b, ctx, kv.Options, kv.Value)
if err != nil {
return nil, err
}
}
if len(t.tables) > 0 {
panic("inline table cannot contain nested tables, only key-values")
}
b = append(b, "}"...)
return b, nil
}
func willConvertToTable(ctx encoderCtx, v reflect.Value) bool {
if !v.IsValid() {
return false
}
if v.Type() == timeType || v.Type().Implements(textMarshalerType) || (v.Kind() != reflect.Ptr && v.CanAddr() && reflect.PtrTo(v.Type()).Implements(textMarshalerType)) {
return false
}
t := v.Type()
switch t.Kind() {
case reflect.Map, reflect.Struct:
return !ctx.inline
case reflect.Interface:
return willConvertToTable(ctx, v.Elem())
case reflect.Ptr:
if v.IsNil() {
return false
}
return willConvertToTable(ctx, v.Elem())
default:
return false
}
}
func willConvertToTableOrArrayTable(ctx encoderCtx, v reflect.Value) bool {
if ctx.insideKv {
return false
}
t := v.Type()
if t.Kind() == reflect.Interface {
return willConvertToTableOrArrayTable(ctx, v.Elem())
}
if t.Kind() == reflect.Slice {
if v.Len() == 0 {
// An empty slice should be a kv = [].
return false
}
for i := 0; i < v.Len(); i++ {
t := willConvertToTable(ctx, v.Index(i))
if !t {
return false
}
}
return true
}
return willConvertToTable(ctx, v)
}
func (enc *Encoder) encodeSlice(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
if v.Len() == 0 {
b = append(b, "[]"...)
return b, nil
}
if willConvertToTableOrArrayTable(ctx, v) {
return enc.encodeSliceAsArrayTable(b, ctx, v)
}
return enc.encodeSliceAsArray(b, ctx, v)
}
// caller should have checked that v is a slice that only contains values that
// encode into tables.
func (enc *Encoder) encodeSliceAsArrayTable(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
ctx.shiftKey()
scratch := make([]byte, 0, 64)
scratch = append(scratch, "[["...)
for i, k := range ctx.parentKey {
if i > 0 {
scratch = append(scratch, '.')
}
scratch = enc.encodeKey(scratch, k)
}
scratch = append(scratch, "]]\n"...)
ctx.skipTableHeader = true
b = enc.encodeComment(ctx.indent, ctx.options.comment, b)
for i := 0; i < v.Len(); i++ {
if i != 0 {
b = append(b, "\n"...)
}
b = append(b, scratch...)
var err error
b, err = enc.encode(b, ctx, v.Index(i))
if err != nil {
return nil, err
}
}
return b, nil
}
func (enc *Encoder) encodeSliceAsArray(b []byte, ctx encoderCtx, v reflect.Value) ([]byte, error) {
multiline := ctx.options.multiline || enc.arraysMultiline
separator := ", "
b = append(b, '[')
subCtx := ctx
subCtx.options = valueOptions{}
if multiline {
separator = ",\n"
b = append(b, '\n')
subCtx.indent++
}
var err error
first := true
for i := 0; i < v.Len(); i++ {
if first {
first = false
} else {
b = append(b, separator...)
}
if multiline {
b = enc.indent(subCtx.indent, b)
}
b, err = enc.encode(b, subCtx, v.Index(i))
if err != nil {
return nil, err
}
}
if multiline {
b = append(b, '\n')
b = enc.indent(ctx.indent, b)
}
b = append(b, ']')
return b, nil
}
func (enc *Encoder) indent(level int, b []byte) []byte {
for i := 0; i < level; i++ {
b = append(b, enc.indentSymbol...)
}
return b
}