chord/vendor/github.com/go-json-experiment/json/internal/jsonflags/flags.go
2025-03-15 20:42:37 -04:00

204 lines
8.1 KiB
Go

// Copyright 2023 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.
// jsonflags implements all the optional boolean flags.
// These flags are shared across both "json", "jsontext", and "jsonopts".
package jsonflags
import "github.com/go-json-experiment/json/internal"
// Bools represents zero or more boolean flags, all set to true or false.
// The least-significant bit is the boolean value of all flags in the set.
// The remaining bits identify which particular flags.
//
// In common usage, this is OR'd with 0 or 1. For example:
// - (AllowInvalidUTF8 | 0) means "AllowInvalidUTF8 is false"
// - (Multiline | Indent | 1) means "Multiline and Indent are true"
type Bools uint64
func (Bools) JSONOptions(internal.NotForPublicUse) {}
const (
// AllFlags is the set of all flags.
AllFlags = AllCoderFlags | AllArshalV2Flags | AllArshalV1Flags
// AllCoderFlags is the set of all encoder/decoder flags.
AllCoderFlags = (maxCoderFlag - 1) - initFlag
// AllArshalV2Flags is the set of all v2 marshal/unmarshal flags.
AllArshalV2Flags = (maxArshalV2Flag - 1) - (maxCoderFlag - 1)
// AllArshalV1Flags is the set of all v1 marshal/unmarshal flags.
AllArshalV1Flags = (maxArshalV1Flag - 1) - (maxArshalV2Flag - 1)
// NonBooleanFlags is the set of non-boolean flags,
// where the value is some other concrete Go type.
// The value of the flag is stored within jsonopts.Struct.
NonBooleanFlags = 0 |
Indent |
IndentPrefix |
ByteLimit |
DepthLimit |
Marshalers |
Unmarshalers
// DefaultV1Flags is the set of booleans flags that default to true under
// v1 semantics. None of the non-boolean flags differ between v1 and v2.
DefaultV1Flags = 0 |
AllowDuplicateNames |
AllowInvalidUTF8 |
EscapeForHTML |
EscapeForJS |
EscapeInvalidUTF8 |
PreserveRawStrings |
Deterministic |
FormatNilMapAsNull |
FormatNilSliceAsNull |
MatchCaseInsensitiveNames |
CallMethodsWithLegacySemantics |
FormatBytesWithLegacySemantics |
FormatTimeWithLegacySemantics |
MatchCaseSensitiveDelimiter |
MergeWithLegacySemantics |
OmitEmptyWithLegacyDefinition |
ReportErrorsWithLegacySemantics |
StringifyWithLegacySemantics |
UnmarshalArrayFromAnyLength
// AnyWhitespace reports whether the encoded output might have any whitespace.
AnyWhitespace = Multiline | SpaceAfterColon | SpaceAfterComma
// WhitespaceFlags is the set of flags related to whitespace formatting.
// In contrast to AnyWhitespace, this includes Indent and IndentPrefix
// as those settings take no effect if Multiline is false.
WhitespaceFlags = AnyWhitespace | Indent | IndentPrefix
// AnyEscape is the set of flags related to escaping in a JSON string.
AnyEscape = EscapeForHTML | EscapeForJS | EscapeInvalidUTF8
// CanonicalizeNumbers is the set of flags related to raw number canonicalization.
CanonicalizeNumbers = CanonicalizeRawInts | CanonicalizeRawFloats
)
// Encoder and decoder flags.
const (
initFlag Bools = 1 << iota // reserved for the boolean value itself
AllowDuplicateNames // encode or decode
AllowInvalidUTF8 // encode or decode
WithinArshalCall // encode or decode; for internal use by json.Marshal and json.Unmarshal
OmitTopLevelNewline // encode only; for internal use by json.Marshal and json.MarshalWrite
PreserveRawStrings // encode only
CanonicalizeRawInts // encode only
CanonicalizeRawFloats // encode only
ReorderRawObjects // encode only
EscapeForHTML // encode only
EscapeForJS // encode only
EscapeInvalidUTF8 // encode only; only exposed in v1
Multiline // encode only
SpaceAfterColon // encode only
SpaceAfterComma // encode only
Indent // encode only; non-boolean flag
IndentPrefix // encode only; non-boolean flag
ByteLimit // encode or decode; non-boolean flag
DepthLimit // encode or decode; non-boolean flag
maxCoderFlag
)
// Marshal and Unmarshal flags (for v2).
const (
_ Bools = (maxCoderFlag >> 1) << iota
StringifyNumbers // marshal or unmarshal
Deterministic // marshal only
FormatNilMapAsNull // marshal only
FormatNilSliceAsNull // marshal only
OmitZeroStructFields // marshal only
MatchCaseInsensitiveNames // marshal or unmarshal
DiscardUnknownMembers // marshal only
RejectUnknownMembers // unmarshal only
Marshalers // marshal only; non-boolean flag
Unmarshalers // unmarshal only; non-boolean flag
maxArshalV2Flag
)
// Marshal and Unmarshal flags (for v1).
const (
_ Bools = (maxArshalV2Flag >> 1) << iota
CallMethodsWithLegacySemantics // marshal or unmarshal
FormatBytesWithLegacySemantics // marshal or unmarshal
FormatTimeWithLegacySemantics // marshal or unmarshal
MatchCaseSensitiveDelimiter // marshal or unmarshal
MergeWithLegacySemantics // unmarshal
OmitEmptyWithLegacyDefinition // marshal
ReportErrorsWithLegacySemantics // marshal or unmarshal
StringifyWithLegacySemantics // marshal or unmarshal
StringifyBoolsAndStrings // marshal or unmarshal; for internal use by jsonv2.makeStructArshaler
UnmarshalAnyWithRawNumber // unmarshal; for internal use by jsonv1.Decoder.UseNumber
UnmarshalArrayFromAnyLength // unmarshal
maxArshalV1Flag
)
// Flags is a set of boolean flags.
// If the presence bit is zero, then the value bit must also be zero.
// The least-significant bit of both fields is always zero.
//
// Unlike Bools, which can represent a set of bools that are all true or false,
// Flags represents a set of bools, each individually may be true or false.
type Flags struct{ Presence, Values uint64 }
// Join joins two sets of flags such that the latter takes precedence.
func (dst *Flags) Join(src Flags) {
// Copy over all source presence bits over to the destination (using OR),
// then invert the source presence bits to clear out source value (using AND-NOT),
// then copy over source value bits over to the destination (using OR).
// e.g., dst := Flags{Presence: 0b_1100_0011, Value: 0b_1000_0011}
// e.g., src := Flags{Presence: 0b_0101_1010, Value: 0b_1001_0010}
dst.Presence |= src.Presence // e.g., 0b_1100_0011 | 0b_0101_1010 -> 0b_110_11011
dst.Values &= ^src.Presence // e.g., 0b_1000_0011 & 0b_1010_0101 -> 0b_100_00001
dst.Values |= src.Values // e.g., 0b_1000_0001 | 0b_1001_0010 -> 0b_100_10011
}
// Set sets both the presence and value for the provided bool (or set of bools).
func (fs *Flags) Set(f Bools) {
// Select out the bits for the flag identifiers (everything except LSB),
// then set the presence for all the identifier bits (using OR),
// then invert the identifier bits to clear out the values (using AND-NOT),
// then copy over all the identifier bits to the value if LSB is 1.
// e.g., fs := Flags{Presence: 0b_0101_0010, Value: 0b_0001_0010}
// e.g., f := 0b_1001_0001
id := uint64(f) &^ uint64(1) // e.g., 0b_1001_0001 & 0b_1111_1110 -> 0b_1001_0000
fs.Presence |= id // e.g., 0b_0101_0010 | 0b_1001_0000 -> 0b_1101_0011
fs.Values &= ^id // e.g., 0b_0001_0010 & 0b_0110_1111 -> 0b_0000_0010
fs.Values |= uint64(f&1) * id // e.g., 0b_0000_0010 | 0b_1001_0000 -> 0b_1001_0010
}
// Get reports whether the bool (or any of the bools) is true.
// This is generally only used with a singular bool.
// The value bit of f (i.e., the LSB) is ignored.
func (fs Flags) Get(f Bools) bool {
return fs.Values&uint64(f) > 0
}
// Has reports whether the bool (or any of the bools) is set.
// The value bit of f (i.e., the LSB) is ignored.
func (fs Flags) Has(f Bools) bool {
return fs.Presence&uint64(f) > 0
}
// Clear clears both the presence and value for the provided bool or bools.
// The value bit of f (i.e., the LSB) is ignored.
func (fs *Flags) Clear(f Bools) {
// Invert f to produce a mask to clear all bits in f (using AND).
// e.g., fs := Flags{Presence: 0b_0101_0010, Value: 0b_0001_0010}
// e.g., f := 0b_0001_1000
mask := uint64(^f) // e.g., 0b_0001_1000 -> 0b_1110_0111
fs.Presence &= mask // e.g., 0b_0101_0010 & 0b_1110_0111 -> 0b_0100_0010
fs.Values &= mask // e.g., 0b_0001_0010 & 0b_1110_0111 -> 0b_0000_0010
}