Update dependencies

vendor/github.com/go-json-experiment/json/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at https://tip.golang.org/AUTHORS.

vendor/github.com/go-json-experiment/json/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at https://tip.golang.org/CONTRIBUTORS.

vendor/github.com/go-json-experiment/json/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2020 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/go-json-experiment/json/README.md

@@ -0,0 +1,177 @@
+# JSON Serialization (v2)
+
+[![GoDev](https://img.shields.io/static/v1?label=godev&message=reference&color=00add8)](https://pkg.go.dev/github.com/go-json-experiment/json)
+[![Build Status](https://github.com/go-json-experiment/json/actions/workflows/test.yml/badge.svg?branch=master)](https://github.com/go-json-experiment/json/actions)
+
+This module hosts an experimental implementation of v2 `encoding/json`.
+The API is unstable and breaking changes will regularly be made.
+Do not depend on this in publicly available modules.
+
+Any commits that make breaking API or behavior changes will be marked
+with the string "WARNING: " near the top of the commit message.
+It is your responsibility to inspect the list of commit changes
+when upgrading the module. Not all breaking changes will lead to build failures.
+
+A [Discussion about including this package in Go as `encoding/json/v2`](https://github.com/golang/go/discussions/63397) has been started on the Go Github project on 2023-10-05. Please provide your feedback there.
+
+## Goals and objectives
+
+* **Mostly backwards compatible:** If possible, v2 should aim to be _mostly_
+compatible with v1 in terms of both API and default behavior to ease migration.
+For example, the `Marshal` and `Unmarshal` functions are the most widely used
+declarations in the v1 package. It seems sensible for equivalent functionality
+in v2 to be named the same and have a mostly compatible signature.
+Behaviorally, we should aim for 95% to 99% backwards compatibility.
+We do not aim for 100% compatibility since we want the freedom to break
+certain behaviors that are now considered to have been a mistake.
+We may provide options that can bring the v2 implementation to 100% compatibility,
+but it will not be the default.
+
+* **More flexible:** There is a
+[long list of feature requests](https://github.com/golang/go/issues?q=is%3Aissue+is%3Aopen+encoding%2Fjson+in%3Atitle).
+We should aim to provide the most flexible features that addresses most usages.
+We do not want to over fit the v2 API to handle every possible use case.
+Ideally, the features provided should be orthogonal in nature such that
+any combination of features results in as few surprising edge cases as possible.
+
+* **More performant:** JSON serialization is widely used and any bit of extra
+performance gains will be greatly appreciated. Some rarely used behaviors of v1
+may be dropped in favor of better performance. For example,
+despite `Encoder` and `Decoder` operating on an `io.Writer` and `io.Reader`,
+they do not operate in a truly streaming manner,
+leading to a loss in performance. The v2 implementation should aim to be truly
+streaming by default (see [#33714](https://golang.org/issue/33714)).
+
+* **Easy to use (hard to misuse):** The v2 API should aim to make
+the common case easy and the less common case at least possible.
+The API should avoid behavior that goes contrary to user expectation,
+which may result in subtle bugs (see [#36225](https://golang.org/issue/36225)).
+
+* **v1 and v2 maintainability:** Since the v1 implementation must stay forever,
+it would be beneficial if v1 could be implemented under the hood with v2,
+allowing for less maintenance burden in the future. This probably implies that
+behavioral changes in v2 relative to v1 need to be exposed as options.
+
+* **Avoid unsafe:** Standard library packages generally avoid the use of
+package `unsafe` even if it could provide a performance boost.
+We aim to preserve this property.
+
+## Expectations
+
+While this module aims to possibly be the v2 implementation of `encoding/json`,
+there is no guarantee that this outcome will occur. As with any major change
+to the Go standard library, this will eventually go through the
+[Go proposal process](https://github.com/golang/proposal#readme).
+At the present moment, this is still in the design and experimentation phase
+and is not ready for a formal proposal.
+
+There are several possible outcomes from this experiment:
+1. We determine that a v2 `encoding/json` would not provide sufficient benefit
+over the existing v1 `encoding/json` package. Thus, we abandon this effort.
+2. We propose a v2 `encoding/json` design, but it is rejected in favor of some
+other design that is considered superior.
+3. We propose a v2 `encoding/json` design, but rather than adding an entirely
+new v2 `encoding/json` package, we decide to merge its functionality into
+the existing v1 `encoding/json` package.
+4. We propose a v2 `encoding/json` design and it is accepted, resulting in
+its addition to the standard library.
+5. Some other unforeseen outcome (among the infinite number of possibilities).
+
+## Development
+
+This module is primarily developed by
+[@dsnet](https://github.com/dsnet),
+[@mvdan](https://github.com/mvdan), and
+[@johanbrandhorst](https://github.com/johanbrandhorst)
+with feedback provided by
+[@rogpeppe](https://github.com/rogpeppe),
+[@ChrisHines](https://github.com/ChrisHines), and
+[@rsc](https://github.com/rsc).
+
+Discussion about semantics occur semi-regularly, where a
+[record of past meetings can be found here](https://docs.google.com/document/d/1rovrOTd-wTawGMPPlPuKhwXaYBg9VszTXR9AQQL5LfI/edit?usp=sharing).
+
+## Design overview
+
+This package aims to provide a clean separation between syntax and semantics.
+Syntax deals with the structural representation of JSON (as specified in
+[RFC 4627](https://tools.ietf.org/html/rfc4627),
+[RFC 7159](https://tools.ietf.org/html/rfc7159),
+[RFC 7493](https://tools.ietf.org/html/rfc7493),
+[RFC 8259](https://tools.ietf.org/html/rfc8259), and
+[RFC 8785](https://tools.ietf.org/html/rfc8785)).
+Semantics deals with the meaning of syntactic data as usable application data.
+
+The `Encoder` and `Decoder` types are streaming tokenizers concerned with the
+packing or parsing of JSON data. They operate on `Token` and `Value` types
+which represent the common data structures that are representable in JSON.
+`Encoder` and `Decoder` do not aim to provide any interpretation of the data.
+
+Functions like `Marshal`, `MarshalWrite`, `MarshalEncode`, `Unmarshal`,
+`UnmarshalRead`, and `UnmarshalDecode` provide semantic meaning by correlating
+any arbitrary Go type with some JSON representation of that type (as stored in
+data types like `[]byte`, `io.Writer`, `io.Reader`, `Encoder`, or `Decoder`).
+
+![API overview](api.png)
+
+This diagram provides a high-level overview of the v2 `json` and `jsontext` packages.
+Purple blocks represent types, while blue blocks represent functions or methods.
+The arrows and their direction represent the approximate flow of data.
+The bottom half of the diagram contains functionality that is only concerned
+with syntax (implemented by the `jsontext` package),
+while the upper half contains functionality that assigns
+semantic meaning to syntactic data handled by the bottom half
+(as implemented by the v2 `json` package).
+
+In contrast to v1 `encoding/json`, options are represented as separate types
+rather than being setter methods on the `Encoder` or `Decoder` types.
+Some options affects JSON serialization at the syntactic layer,
+while others affect it at the semantic layer.
+Some options only affect JSON when decoding,
+while others affect JSON while encoding.
+
+## Behavior changes
+
+The v2 `json` package changes the default behavior of `Marshal` and `Unmarshal`
+relative to the v1 `json` package to be more sensible.
+Some of these behavior changes have options and workarounds to opt into
+behavior similar to what v1 provided.
+
+This table shows an overview of the changes:
+
+| v1 | v2 | Details |
+| -- | -- | ------- |
+| JSON object members are unmarshaled into a Go struct using a **case-insensitive name match**. | JSON object members are unmarshaled into a Go struct using a **case-sensitive name match**. | [CaseSensitivity](/diff_test.go#:~:text=TestCaseSensitivity) |
+| When marshaling a Go struct, a struct field marked as `omitempty` is omitted if **the field value is an empty Go value**, which is defined as false, 0, a nil pointer, a nil interface value, and any empty array, slice, map, or string. | When marshaling a Go struct, a struct field marked as `omitempty` is omitted if **the field value would encode as an empty JSON value**, which is defined as a JSON null, or an empty JSON string, object, or array. | [OmitEmptyOption](/diff_test.go#:~:text=TestOmitEmptyOption) |
+| The `string` option **does affect** Go bools. | The `string` option **does not affect** Go bools. | [StringOption](/diff_test.go#:~:text=TestStringOption) |
+| The `string` option **does not recursively affect** sub-values of the Go field value. | The `string` option **does recursively affect** sub-values of the Go field value. | [StringOption](/diff_test.go#:~:text=TestStringOption) |
+| The `string` option **sometimes accepts** a JSON null escaped within a JSON string. | The `string` option **never accepts** a JSON null escaped within a JSON string. | [StringOption](/diff_test.go#:~:text=TestStringOption) |
+| A nil Go slice is marshaled as a **JSON null**. | A nil Go slice is marshaled as an **empty JSON array**. | [NilSlicesAndMaps](/diff_test.go#:~:text=TestNilSlicesAndMaps) |
+| A nil Go map is marshaled as a **JSON null**. | A nil Go map is marshaled as an **empty JSON object**. | [NilSlicesAndMaps](/diff_test.go#:~:text=TestNilSlicesAndMaps) |
+| A Go array may be unmarshaled from a **JSON array of any length**. | A Go array must be unmarshaled from a **JSON array of the same length**. | [Arrays](/diff_test.go#:~:text=Arrays) |
+| A Go byte array is represented as a **JSON array of JSON numbers**. | A Go byte array is represented as a **Base64-encoded JSON string**. | [ByteArrays](/diff_test.go#:~:text=TestByteArrays) |
+| `MarshalJSON` and `UnmarshalJSON` methods declared on a pointer receiver are **inconsistently called**. | `MarshalJSON` and `UnmarshalJSON` methods declared on a pointer receiver are **consistently called**. | [PointerReceiver](/diff_test.go#:~:text=TestPointerReceiver) |
+| A Go map is marshaled in a **deterministic order**. | A Go map is marshaled in a **non-deterministic order**. | [MapDeterminism](/diff_test.go#:~:text=TestMapDeterminism) |
+| JSON strings are encoded **with HTML-specific characters being escaped**. | JSON strings are encoded **without any characters being escaped** (unless necessary). | [EscapeHTML](/diff_test.go#:~:text=TestEscapeHTML) |
+| When marshaling, invalid UTF-8 within a Go string **are silently replaced**. | When marshaling, invalid UTF-8 within a Go string **results in an error**. | [InvalidUTF8](/diff_test.go#:~:text=TestInvalidUTF8) |
+| When unmarshaling, invalid UTF-8 within a JSON string **are silently replaced**. | When unmarshaling, invalid UTF-8 within a JSON string **results in an error**. | [InvalidUTF8](/diff_test.go#:~:text=TestInvalidUTF8) |
+| When marshaling, **an error does not occur** if the output JSON value contains objects with duplicate names. | When marshaling, **an error does occur** if the output JSON value contains objects with duplicate names. | [DuplicateNames](/diff_test.go#:~:text=TestDuplicateNames) |
+| When unmarshaling, **an error does not occur** if the input JSON value contains objects with duplicate names. | When unmarshaling, **an error does occur** if the input JSON value contains objects with duplicate names. | [DuplicateNames](/diff_test.go#:~:text=TestDuplicateNames) |
+| Unmarshaling a JSON null into a non-empty Go value **inconsistently clears the value or does nothing**. | Unmarshaling a JSON null into a non-empty Go value **always clears the value**. | [MergeNull](/diff_test.go#:~:text=TestMergeNull) |
+| Unmarshaling a JSON value into a non-empty Go value **follows inconsistent and bizarre behavior**. | Unmarshaling a JSON value into a non-empty Go value **always merges if the input is an object, and otherwise replaces**.  | [MergeComposite](/diff_test.go#:~:text=TestMergeComposite) |
+| A `time.Duration` is represented as a **JSON number containing the decimal number of nanoseconds**. | A `time.Duration` is represented as a **JSON string containing the formatted duration (e.g., "1h2m3.456s")**. | [TimeDurations](/diff_test.go#:~:text=TestTimeDurations) |
+| Unmarshaling a JSON number into a Go float beyond its representation **results in an error**. | Unmarshaling a JSON number into a Go float beyond its representation **uses the closest representable value (e.g., ±`math.MaxFloat`)**. | [MaxFloats](/diff_test.go#:~:text=TestMaxFloats) |
+| A Go struct with only unexported fields **can be serialized**. | A Go struct with only unexported fields **cannot be serialized**. | [EmptyStructs](/diff_test.go#:~:text=TestEmptyStructs) |
+| A Go struct that embeds an unexported struct type **can sometimes be serialized**. | A Go struct that embeds an unexported struct type **cannot be serialized**. | [EmbedUnexported](/diff_test.go#:~:text=TestEmbedUnexported) |
+
+See [diff_test.go](/diff_test.go) for details about every change.
+
+## Performance
+
+One of the goals of the v2 module is to be more performant than v1,
+but not at the expense of correctness.
+In general, v2 is at performance parity with v1 for marshaling,
+but dramatically faster for unmarshaling.
+
+See https://github.com/go-json-experiment/jsonbench for benchmarks
+comparing v2 with v1 and a number of other popular JSON implementations.

vendor/github.com/go-json-experiment/json/arshal.go

@@ -0,0 +1,531 @@
+// 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 json
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"reflect"
+	"slices"
+	"sync"
+
+	"github.com/go-json-experiment/json/internal"
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+// export exposes internal functionality of the "jsontext" package.
+var export = jsontext.Internal.Export(&internal.AllowInternalUse)
+
+var structOptionsPool = &sync.Pool{New: func() any { return new(jsonopts.Struct) }}
+
+func getStructOptions() *jsonopts.Struct {
+	return structOptionsPool.Get().(*jsonopts.Struct)
+}
+func putStructOptions(o *jsonopts.Struct) {
+	*o = jsonopts.Struct{}
+	structOptionsPool.Put(o)
+}
+
+// Marshal serializes a Go value as a []byte according to the provided
+// marshal and encode options (while ignoring unmarshal or decode options).
+// It does not terminate the output with a newline.
+//
+// Type-specific marshal functions and methods take precedence
+// over the default representation of a value.
+// Functions or methods that operate on *T are only called when encoding
+// a value of type T (by taking its address) or a non-nil value of *T.
+// Marshal ensures that a value is always addressable
+// (by boxing it on the heap if necessary) so that
+// these functions and methods can be consistently called. For performance,
+// it is recommended that Marshal be passed a non-nil pointer to the value.
+//
+// The input value is encoded as JSON according the following rules:
+//
+//   - If any type-specific functions in a [WithMarshalers] option match
+//     the value type, then those functions are called to encode the value.
+//     If all applicable functions return [SkipFunc],
+//     then the value is encoded according to subsequent rules.
+//
+//   - If the value type implements [MarshalerV2],
+//     then the MarshalJSONV2 method is called to encode the value.
+//
+//   - If the value type implements [MarshalerV1],
+//     then the MarshalJSON method is called to encode the value.
+//
+//   - If the value type implements [encoding.TextMarshaler],
+//     then the MarshalText method is called to encode the value and
+//     subsequently encode its result as a JSON string.
+//
+//   - Otherwise, the value is encoded according to the value's type
+//     as described in detail below.
+//
+// Most Go types have a default JSON representation.
+// Certain types support specialized formatting according to
+// a format flag optionally specified in the Go struct tag
+// for the struct field that contains the current value
+// (see the “JSON Representation of Go structs” section for more details).
+//
+// The representation of each type is as follows:
+//
+//   - A Go boolean is encoded as a JSON boolean (e.g., true or false).
+//     It does not support any custom format flags.
+//
+//   - A Go string is encoded as a JSON string.
+//     It does not support any custom format flags.
+//
+//   - A Go []byte or [N]byte is encoded as a JSON string containing
+//     the binary value encoded using RFC 4648.
+//     If the format is "base64" or unspecified, then this uses RFC 4648, section 4.
+//     If the format is "base64url", then this uses RFC 4648, section 5.
+//     If the format is "base32", then this uses RFC 4648, section 6.
+//     If the format is "base32hex", then this uses RFC 4648, section 7.
+//     If the format is "base16" or "hex", then this uses RFC 4648, section 8.
+//     If the format is "array", then the bytes value is encoded as a JSON array
+//     where each byte is recursively JSON-encoded as each JSON array element.
+//
+//   - A Go integer is encoded as a JSON number without fractions or exponents.
+//     If [StringifyNumbers] is specified, then the JSON number is
+//     encoded within a JSON string. It does not support any custom format flags.
+//
+//   - A Go float is encoded as a JSON number.
+//     If [StringifyNumbers] is specified,
+//     then the JSON number is encoded within a JSON string.
+//     If the format is "nonfinite", then NaN, +Inf, and -Inf are encoded as
+//     the JSON strings "NaN", "Infinity", and "-Infinity", respectively.
+//     Otherwise, the presence of non-finite numbers results in a [SemanticError].
+//
+//   - A Go map is encoded as a JSON object, where each Go map key and value
+//     is recursively encoded as a name and value pair in the JSON object.
+//     The Go map key must encode as a JSON string, otherwise this results
+//     in a [SemanticError]. When encoding keys, [StringifyNumbers]
+//     is automatically applied so that numeric keys encode as JSON strings.
+//     The Go map is traversed in a non-deterministic order.
+//     For deterministic encoding, consider using [jsontext.Value.Canonicalize].
+//     If the format is "emitnull", then a nil map is encoded as a JSON null.
+//     If the format is "emitempty", then a nil map is encoded as an empty JSON object,
+//     regardless of whether [FormatNilMapAsNull] is specified.
+//     Otherwise by default, a nil map is encoded as an empty JSON object.
+//
+//   - A Go struct is encoded as a JSON object.
+//     See the “JSON Representation of Go structs” section
+//     in the package-level documentation for more details.
+//
+//   - A Go slice is encoded as a JSON array, where each Go slice element
+//     is recursively JSON-encoded as the elements of the JSON array.
+//     If the format is "emitnull", then a nil slice is encoded as a JSON null.
+//     If the format is "emitempty", then a nil slice is encoded as an empty JSON array,
+//     regardless of whether [FormatNilSliceAsNull] is specified.
+//     Otherwise by default, a nil slice is encoded as an empty JSON array.
+//
+//   - A Go array is encoded as a JSON array, where each Go array element
+//     is recursively JSON-encoded as the elements of the JSON array.
+//     The JSON array length is always identical to the Go array length.
+//     It does not support any custom format flags.
+//
+//   - A Go pointer is encoded as a JSON null if nil, otherwise it is
+//     the recursively JSON-encoded representation of the underlying value.
+//     Format flags are forwarded to the encoding of the underlying value.
+//
+//   - A Go interface is encoded as a JSON null if nil, otherwise it is
+//     the recursively JSON-encoded representation of the underlying value.
+//     It does not support any custom format flags.
+//
+//   - A Go [time.Time] is encoded as a JSON string containing the timestamp
+//     formatted in RFC 3339 with nanosecond precision.
+//     If the format matches one of the format constants declared
+//     in the time package (e.g., RFC1123), then that format is used.
+//     If the format is "unix", "unixmilli", "unixmicro", or "unixnano",
+//     then the timestamp is encoded as a JSON number of the number of seconds
+//     (or milliseconds, microseconds, or nanoseconds) since the Unix epoch,
+//     which is January 1st, 1970 at 00:00:00 UTC.
+//     Otherwise, the format is used as-is with [time.Time.Format] if non-empty.
+//
+//   - A Go [time.Duration] is encoded as a JSON string containing the duration
+//     formatted according to [time.Duration.String].
+//     If the format is "sec", "milli", "micro", or "nano",
+//     then the duration is encoded as a JSON number of the number of seconds
+//     (or milliseconds, microseconds, or nanoseconds) in the duration.
+//     If the format is "base60", it is encoded as a JSON string
+//     using the "H:MM:SS.SSSSSSSSS" representation.
+//     If the format is "units", it uses [time.Duration.String].
+//
+//   - All other Go types (e.g., complex numbers, channels, and functions)
+//     have no default representation and result in a [SemanticError].
+//
+// JSON cannot represent cyclic data structures and Marshal does not handle them.
+// Passing cyclic structures will result in an error.
+func Marshal(in any, opts ...Options) (out []byte, err error) {
+	enc := export.GetBufferedEncoder(opts...)
+	defer export.PutBufferedEncoder(enc)
+	xe := export.Encoder(enc)
+	xe.Flags.Set(jsonflags.OmitTopLevelNewline | 1)
+	err = marshalEncode(enc, in, &xe.Struct)
+	return bytes.Clone(xe.Buf), err
+}
+
+// MarshalWrite serializes a Go value into an [io.Writer] according to the provided
+// marshal and encode options (while ignoring unmarshal or decode options).
+// It does not terminate the output with a newline.
+// See [Marshal] for details about the conversion of a Go value into JSON.
+func MarshalWrite(out io.Writer, in any, opts ...Options) (err error) {
+	enc := export.GetStreamingEncoder(out, opts...)
+	defer export.PutStreamingEncoder(enc)
+	xe := export.Encoder(enc)
+	xe.Flags.Set(jsonflags.OmitTopLevelNewline | 1)
+	return marshalEncode(enc, in, &xe.Struct)
+}
+
+// MarshalEncode serializes a Go value into an [jsontext.Encoder] according to
+// the provided marshal options (while ignoring unmarshal, encode, or decode options).
+// Unlike [Marshal] and [MarshalWrite], encode options are ignored because
+// they must have already been specified on the provided [jsontext.Encoder].
+// See [Marshal] for details about the conversion of a Go value into JSON.
+func MarshalEncode(out *jsontext.Encoder, in any, opts ...Options) (err error) {
+	mo := getStructOptions()
+	defer putStructOptions(mo)
+	mo.Join(opts...)
+	xe := export.Encoder(out)
+	mo.CopyCoderOptions(&xe.Struct)
+	return marshalEncode(out, in, mo)
+}
+
+func marshalEncode(out *jsontext.Encoder, in any, mo *jsonopts.Struct) (err error) {
+	v := reflect.ValueOf(in)
+	if !v.IsValid() || (v.Kind() == reflect.Pointer && v.IsNil()) {
+		return out.WriteToken(jsontext.Null)
+	}
+	// Shallow copy non-pointer values to obtain an addressable value.
+	// It is beneficial to performance to always pass pointers to avoid this.
+	if v.Kind() != reflect.Pointer {
+		v2 := reflect.New(v.Type())
+		v2.Elem().Set(v)
+		v = v2
+	}
+	va := addressableValue{v.Elem()} // dereferenced pointer is always addressable
+	t := va.Type()
+
+	// Lookup and call the marshal function for this type.
+	marshal := lookupArshaler(t).marshal
+	if mo.Marshalers != nil {
+		marshal, _ = mo.Marshalers.(*Marshalers).lookup(marshal, t)
+	}
+	if err := marshal(out, va, mo); err != nil {
+		xe := export.Encoder(out)
+		if !xe.Flags.Get(jsonflags.AllowDuplicateNames) {
+			xe.Tokens.InvalidateDisabledNamespaces()
+		}
+		return err
+	}
+	return nil
+}
+
+// Unmarshal decodes a []byte input into a Go value according to the provided
+// unmarshal and decode options (while ignoring marshal or encode options).
+// The input must be a single JSON value with optional whitespace interspersed.
+// The output must be a non-nil pointer.
+//
+// Type-specific unmarshal functions and methods take precedence
+// over the default representation of a value.
+// Functions or methods that operate on *T are only called when decoding
+// a value of type T (by taking its address) or a non-nil value of *T.
+// Unmarshal ensures that a value is always addressable
+// (by boxing it on the heap if necessary) so that
+// these functions and methods can be consistently called.
+//
+// The input is decoded into the output according the following rules:
+//
+//   - If any type-specific functions in a [WithUnmarshalers] option match
+//     the value type, then those functions are called to decode the JSON
+//     value. If all applicable functions return [SkipFunc],
+//     then the input is decoded according to subsequent rules.
+//
+//   - If the value type implements [UnmarshalerV2],
+//     then the UnmarshalJSONV2 method is called to decode the JSON value.
+//
+//   - If the value type implements [UnmarshalerV1],
+//     then the UnmarshalJSON method is called to decode the JSON value.
+//
+//   - If the value type implements [encoding.TextUnmarshaler],
+//     then the input is decoded as a JSON string and
+//     the UnmarshalText method is called with the decoded string value.
+//     This fails with a [SemanticError] if the input is not a JSON string.
+//
+//   - Otherwise, the JSON value is decoded according to the value's type
+//     as described in detail below.
+//
+// Most Go types have a default JSON representation.
+// Certain types support specialized formatting according to
+// a format flag optionally specified in the Go struct tag
+// for the struct field that contains the current value
+// (see the “JSON Representation of Go structs” section for more details).
+// A JSON null may be decoded into every supported Go value where
+// it is equivalent to storing the zero value of the Go value.
+// If the input JSON kind is not handled by the current Go value type,
+// then this fails with a [SemanticError]. Unless otherwise specified,
+// the decoded value replaces any pre-existing value.
+//
+// The representation of each type is as follows:
+//
+//   - A Go boolean is decoded from a JSON boolean (e.g., true or false).
+//     It does not support any custom format flags.
+//
+//   - A Go string is decoded from a JSON string.
+//     It does not support any custom format flags.
+//
+//   - A Go []byte or [N]byte is decoded from a JSON string
+//     containing the binary value encoded using RFC 4648.
+//     If the format is "base64" or unspecified, then this uses RFC 4648, section 4.
+//     If the format is "base64url", then this uses RFC 4648, section 5.
+//     If the format is "base32", then this uses RFC 4648, section 6.
+//     If the format is "base32hex", then this uses RFC 4648, section 7.
+//     If the format is "base16" or "hex", then this uses RFC 4648, section 8.
+//     If the format is "array", then the Go slice or array is decoded from a
+//     JSON array where each JSON element is recursively decoded for each byte.
+//     When decoding into a non-nil []byte, the slice length is reset to zero
+//     and the decoded input is appended to it.
+//     When decoding into a [N]byte, the input must decode to exactly N bytes,
+//     otherwise it fails with a [SemanticError].
+//
+//   - A Go integer is decoded from a JSON number.
+//     It may also be decoded from a JSON string containing a JSON number
+//     if [StringifyNumbers] is specified.
+//     It fails with a [SemanticError] if the JSON number
+//     has a fractional or exponent component.
+//     It also fails if it overflows the representation of the Go integer type.
+//     It does not support any custom format flags.
+//
+//   - A Go float is decoded from a JSON number.
+//     It may also be decoded from a JSON string containing a JSON number
+//     if [StringifyNumbers] is specified.
+//     The JSON number is parsed as the closest representable Go float value.
+//     If the format is "nonfinite", then the JSON strings
+//     "NaN", "Infinity", and "-Infinity" are decoded as NaN, +Inf, and -Inf.
+//     Otherwise, the presence of such strings results in a [SemanticError].
+//
+//   - A Go map is decoded from a JSON object,
+//     where each JSON object name and value pair is recursively decoded
+//     as the Go map key and value. When decoding keys,
+//     [StringifyNumbers] is automatically applied so that
+//     numeric keys can decode from JSON strings. Maps are not cleared.
+//     If the Go map is nil, then a new map is allocated to decode into.
+//     If the decoded key matches an existing Go map entry, the entry value
+//     is reused by decoding the JSON object value into it.
+//     The formats "emitnull" and "emitempty" have no effect when decoding.
+//
+//   - A Go struct is decoded from a JSON object.
+//     See the “JSON Representation of Go structs” section
+//     in the package-level documentation for more details.
+//
+//   - A Go slice is decoded from a JSON array, where each JSON element
+//     is recursively decoded and appended to the Go slice.
+//     Before appending into a Go slice, a new slice is allocated if it is nil,
+//     otherwise the slice length is reset to zero.
+//     The formats "emitnull" and "emitempty" have no effect when decoding.
+//
+//   - A Go array is decoded from a JSON array, where each JSON array element
+//     is recursively decoded as each corresponding Go array element.
+//     Each Go array element is zeroed before decoding into it.
+//     It fails with a [SemanticError] if the JSON array does not contain
+//     the exact same number of elements as the Go array.
+//     It does not support any custom format flags.
+//
+//   - A Go pointer is decoded based on the JSON kind and underlying Go type.
+//     If the input is a JSON null, then this stores a nil pointer.
+//     Otherwise, it allocates a new underlying value if the pointer is nil,
+//     and recursively JSON decodes into the underlying value.
+//     Format flags are forwarded to the decoding of the underlying type.
+//
+//   - A Go interface is decoded based on the JSON kind and underlying Go type.
+//     If the input is a JSON null, then this stores a nil interface value.
+//     Otherwise, a nil interface value of an empty interface type is initialized
+//     with a zero Go bool, string, float64, map[string]any, or []any if the
+//     input is a JSON boolean, string, number, object, or array, respectively.
+//     If the interface value is still nil, then this fails with a [SemanticError]
+//     since decoding could not determine an appropriate Go type to decode into.
+//     For example, unmarshaling into a nil io.Reader fails since
+//     there is no concrete type to populate the interface value with.
+//     Otherwise an underlying value exists and it recursively decodes
+//     the JSON input into it. It does not support any custom format flags.
+//
+//   - A Go [time.Time] is decoded from a JSON string containing the time
+//     formatted in RFC 3339 with nanosecond precision.
+//     If the format matches one of the format constants declared in
+//     the time package (e.g., RFC1123), then that format is used for parsing.
+//     If the format is "unix", "unixmilli", "unixmicro", or "unixnano",
+//     then the timestamp is decoded from a JSON number of the number of seconds
+//     (or milliseconds, microseconds, or nanoseconds) since the Unix epoch,
+//     which is January 1st, 1970 at 00:00:00 UTC.
+//     Otherwise, the format is used as-is with [time.Time.Parse] if non-empty.
+//
+//   - A Go [time.Duration] is decoded from a JSON string by
+//     passing the decoded string to [time.ParseDuration].
+//     If the format is "sec", "milli", "micro", or "nano",
+//     then the duration is decoded from a JSON number of the number of seconds
+//     (or milliseconds, microseconds, or nanoseconds) in the duration.
+//     If the format is "base60", it is decoded from a JSON string
+//     using the "H:MM:SS.SSSSSSSSS" representation.
+//     If the format is "units", it uses [time.ParseDuration].
+//
+//   - All other Go types (e.g., complex numbers, channels, and functions)
+//     have no default representation and result in a [SemanticError].
+//
+// In general, unmarshaling follows merge semantics (similar to RFC 7396)
+// where the decoded Go value replaces the destination value
+// for any JSON kind other than an object.
+// For JSON objects, the input object is merged into the destination value
+// where matching object members recursively apply merge semantics.
+func Unmarshal(in []byte, out any, opts ...Options) (err error) {
+	dec := export.GetBufferedDecoder(in, opts...)
+	defer export.PutBufferedDecoder(dec)
+	xd := export.Decoder(dec)
+	return unmarshalFull(dec, out, &xd.Struct)
+}
+
+// UnmarshalRead deserializes a Go value from an [io.Reader] according to the
+// provided unmarshal and decode options (while ignoring marshal or encode options).
+// The input must be a single JSON value with optional whitespace interspersed.
+// It consumes the entirety of [io.Reader] until [io.EOF] is encountered,
+// without reporting an error for EOF. The output must be a non-nil pointer.
+// See [Unmarshal] for details about the conversion of JSON into a Go value.
+func UnmarshalRead(in io.Reader, out any, opts ...Options) (err error) {
+	dec := export.GetStreamingDecoder(in, opts...)
+	defer export.PutStreamingDecoder(dec)
+	xd := export.Decoder(dec)
+	return unmarshalFull(dec, out, &xd.Struct)
+}
+
+func unmarshalFull(in *jsontext.Decoder, out any, uo *jsonopts.Struct) error {
+	switch err := unmarshalDecode(in, out, uo); err {
+	case nil:
+		return export.Decoder(in).CheckEOF()
+	case io.EOF:
+		return io.ErrUnexpectedEOF
+	default:
+		return err
+	}
+}
+
+// UnmarshalDecode deserializes a Go value from a [jsontext.Decoder] according to
+// the provided unmarshal options (while ignoring marshal, encode, or decode options).
+// Unlike [Unmarshal] and [UnmarshalRead], decode options are ignored because
+// they must have already been specified on the provided [jsontext.Decoder].
+// The input may be a stream of one or more JSON values,
+// where this only unmarshals the next JSON value in the stream.
+// The output must be a non-nil pointer.
+// See [Unmarshal] for details about the conversion of JSON into a Go value.
+func UnmarshalDecode(in *jsontext.Decoder, out any, opts ...Options) (err error) {
+	uo := getStructOptions()
+	defer putStructOptions(uo)
+	uo.Join(opts...)
+	xd := export.Decoder(in)
+	uo.CopyCoderOptions(&xd.Struct)
+	return unmarshalDecode(in, out, uo)
+}
+
+func unmarshalDecode(in *jsontext.Decoder, out any, uo *jsonopts.Struct) (err error) {
+	v := reflect.ValueOf(out)
+	if !v.IsValid() || v.Kind() != reflect.Pointer || v.IsNil() {
+		var t reflect.Type
+		if v.IsValid() {
+			t = v.Type()
+			if t.Kind() == reflect.Pointer {
+				t = t.Elem()
+			}
+		}
+		err := errors.New("value must be passed as a non-nil pointer reference")
+		return &SemanticError{action: "unmarshal", GoType: t, Err: err}
+	}
+	va := addressableValue{v.Elem()} // dereferenced pointer is always addressable
+	t := va.Type()
+
+	// Lookup and call the unmarshal function for this type.
+	unmarshal := lookupArshaler(t).unmarshal
+	if uo.Unmarshalers != nil {
+		unmarshal, _ = uo.Unmarshalers.(*Unmarshalers).lookup(unmarshal, t)
+	}
+	if err := unmarshal(in, va, uo); err != nil {
+		xd := export.Decoder(in)
+		if !xd.Flags.Get(jsonflags.AllowDuplicateNames) {
+			xd.Tokens.InvalidateDisabledNamespaces()
+		}
+		return err
+	}
+	return nil
+}
+
+// addressableValue is a reflect.Value that is guaranteed to be addressable
+// such that calling the Addr and Set methods do not panic.
+//
+// There is no compile magic that enforces this property,
+// but rather the need to construct this type makes it easier to examine each
+// construction site to ensure that this property is upheld.
+type addressableValue struct{ reflect.Value }
+
+// newAddressableValue constructs a new addressable value of type t.
+func newAddressableValue(t reflect.Type) addressableValue {
+	return addressableValue{reflect.New(t).Elem()}
+}
+
+// All marshal and unmarshal behavior is implemented using these signatures.
+// The *jsonopts.Struct argument is guaranteed to identical to or at least
+// a strict super-set of the options in Encoder.Struct or Decoder.Struct.
+// It is identical for Marshal, Unmarshal, MarshalWrite, and UnmarshalRead.
+// It is a super-set for MarshalEncode and UnmarshalDecode.
+type (
+	marshaler   = func(*jsontext.Encoder, addressableValue, *jsonopts.Struct) error
+	unmarshaler = func(*jsontext.Decoder, addressableValue, *jsonopts.Struct) error
+)
+
+type arshaler struct {
+	marshal    marshaler
+	unmarshal  unmarshaler
+	nonDefault bool
+}
+
+var lookupArshalerCache sync.Map // map[reflect.Type]*arshaler
+
+func lookupArshaler(t reflect.Type) *arshaler {
+	if v, ok := lookupArshalerCache.Load(t); ok {
+		return v.(*arshaler)
+	}
+
+	fncs := makeDefaultArshaler(t)
+	fncs = makeMethodArshaler(fncs, t)
+	fncs = makeTimeArshaler(fncs, t)
+
+	// Use the last stored so that duplicate arshalers can be garbage collected.
+	v, _ := lookupArshalerCache.LoadOrStore(t, fncs)
+	return v.(*arshaler)
+}
+
+var stringsPools = &sync.Pool{New: func() any { return new(stringSlice) }}
+
+type stringSlice []string
+
+// getStrings returns a non-nil pointer to a slice with length n.
+func getStrings(n int) *stringSlice {
+	s := stringsPools.Get().(*stringSlice)
+	if cap(*s) < n {
+		*s = make([]string, n)
+	}
+	*s = (*s)[:n]
+	return s
+}
+
+func putStrings(s *stringSlice) {
+	if cap(*s) > 1<<10 {
+		*s = nil // avoid pinning arbitrarily large amounts of memory
+	}
+	stringsPools.Put(s)
+}
+
+// Sort sorts the string slice according to RFC 8785, section 3.2.3.
+func (ss *stringSlice) Sort() {
+	slices.SortFunc(*ss, func(x, y string) int { return jsonwire.CompareUTF16(x, y) })
+}

vendor/github.com/go-json-experiment/json/arshal_any.go

@@ -0,0 +1,263 @@
+// Copyright 2022 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 json
+
+import (
+	"reflect"
+	"strconv"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+// This file contains an optimized marshal and unmarshal implementation
+// for the any type. This type is often used when the Go program has
+// no knowledge of the JSON schema. This is a common enough occurrence
+// to justify the complexity of adding logic for this.
+
+func marshalValueAny(enc *jsontext.Encoder, val any, mo *jsonopts.Struct) error {
+	switch val := val.(type) {
+	case nil:
+		return enc.WriteToken(jsontext.Null)
+	case bool:
+		return enc.WriteToken(jsontext.Bool(val))
+	case string:
+		return enc.WriteToken(jsontext.String(val))
+	case float64:
+		return enc.WriteToken(jsontext.Float(val))
+	case map[string]any:
+		return marshalObjectAny(enc, val, mo)
+	case []any:
+		return marshalArrayAny(enc, val, mo)
+	default:
+		v := newAddressableValue(reflect.TypeOf(val))
+		v.Set(reflect.ValueOf(val))
+		marshal := lookupArshaler(v.Type()).marshal
+		if mo.Marshalers != nil {
+			marshal, _ = mo.Marshalers.(*Marshalers).lookup(marshal, v.Type())
+		}
+		return marshal(enc, v, mo)
+	}
+}
+
+func unmarshalValueAny(dec *jsontext.Decoder, uo *jsonopts.Struct) (any, error) {
+	switch k := dec.PeekKind(); k {
+	case '{':
+		return unmarshalObjectAny(dec, uo)
+	case '[':
+		return unmarshalArrayAny(dec, uo)
+	default:
+		xd := export.Decoder(dec)
+		var flags jsonwire.ValueFlags
+		val, err := xd.ReadValue(&flags)
+		if err != nil {
+			return nil, err
+		}
+		switch val.Kind() {
+		case 'n':
+			return nil, nil
+		case 'f':
+			return false, nil
+		case 't':
+			return true, nil
+		case '"':
+			val = jsonwire.UnquoteMayCopy(val, flags.IsVerbatim())
+			if xd.StringCache == nil {
+				xd.StringCache = new(stringCache)
+			}
+			return makeString(xd.StringCache, val), nil
+		case '0':
+			fv, ok := jsonwire.ParseFloat(val, 64)
+			if !ok && uo.Flags.Get(jsonflags.RejectFloatOverflow) {
+				return nil, &SemanticError{action: "unmarshal", JSONKind: k, GoType: float64Type, Err: strconv.ErrRange}
+			}
+			return fv, nil
+		default:
+			panic("BUG: invalid kind: " + k.String())
+		}
+	}
+}
+
+func marshalObjectAny(enc *jsontext.Encoder, obj map[string]any, mo *jsonopts.Struct) error {
+	// Check for cycles.
+	xe := export.Encoder(enc)
+	if xe.Tokens.Depth() > startDetectingCyclesAfter {
+		v := reflect.ValueOf(obj)
+		if err := visitPointer(&xe.SeenPointers, v); err != nil {
+			return err
+		}
+		defer leavePointer(&xe.SeenPointers, v)
+	}
+
+	// Handle empty maps.
+	if len(obj) == 0 {
+		if mo.Flags.Get(jsonflags.FormatNilMapAsNull) && obj == nil {
+			return enc.WriteToken(jsontext.Null)
+		}
+		// Optimize for marshaling an empty map without any preceding whitespace.
+		if !xe.Flags.Get(jsonflags.Expand) && !xe.Tokens.Last.NeedObjectName() {
+			xe.Buf = append(xe.Tokens.MayAppendDelim(xe.Buf, '{'), "{}"...)
+			xe.Tokens.Last.Increment()
+			if xe.NeedFlush() {
+				return xe.Flush()
+			}
+			return nil
+		}
+	}
+
+	if err := enc.WriteToken(jsontext.ObjectStart); err != nil {
+		return err
+	}
+	// A Go map guarantees that each entry has a unique key
+	// The only possibility of duplicates is due to invalid UTF-8.
+	if !xe.Flags.Get(jsonflags.AllowInvalidUTF8) {
+		xe.Tokens.Last.DisableNamespace()
+	}
+	if !mo.Flags.Get(jsonflags.Deterministic) || len(obj) <= 1 {
+		for name, val := range obj {
+			if err := enc.WriteToken(jsontext.String(name)); err != nil {
+				return err
+			}
+			if err := marshalValueAny(enc, val, mo); err != nil {
+				return err
+			}
+		}
+	} else {
+		names := getStrings(len(obj))
+		var i int
+		for name := range obj {
+			(*names)[i] = name
+			i++
+		}
+		names.Sort()
+		for _, name := range *names {
+			if err := enc.WriteToken(jsontext.String(name)); err != nil {
+				return err
+			}
+			if err := marshalValueAny(enc, obj[name], mo); err != nil {
+				return err
+			}
+		}
+		putStrings(names)
+	}
+	if err := enc.WriteToken(jsontext.ObjectEnd); err != nil {
+		return err
+	}
+	return nil
+}
+
+func unmarshalObjectAny(dec *jsontext.Decoder, uo *jsonopts.Struct) (map[string]any, error) {
+	tok, err := dec.ReadToken()
+	if err != nil {
+		return nil, err
+	}
+	k := tok.Kind()
+	switch k {
+	case 'n':
+		return nil, nil
+	case '{':
+		xd := export.Decoder(dec)
+		obj := make(map[string]any)
+		// A Go map guarantees that each entry has a unique key
+		// The only possibility of duplicates is due to invalid UTF-8.
+		if !xd.Flags.Get(jsonflags.AllowInvalidUTF8) {
+			xd.Tokens.Last.DisableNamespace()
+		}
+		for dec.PeekKind() != '}' {
+			tok, err := dec.ReadToken()
+			if err != nil {
+				return obj, err
+			}
+			name := tok.String()
+
+			// Manually check for duplicate names.
+			if _, ok := obj[name]; ok {
+				name := xd.PreviousBuffer()
+				err := export.NewDuplicateNameError(name, dec.InputOffset()-len64(name))
+				return obj, err
+			}
+
+			val, err := unmarshalValueAny(dec, uo)
+			obj[name] = val
+			if err != nil {
+				return obj, err
+			}
+		}
+		if _, err := dec.ReadToken(); err != nil {
+			return obj, err
+		}
+		return obj, nil
+	}
+	return nil, &SemanticError{action: "unmarshal", JSONKind: k, GoType: mapStringAnyType}
+}
+
+func marshalArrayAny(enc *jsontext.Encoder, arr []any, mo *jsonopts.Struct) error {
+	// Check for cycles.
+	xe := export.Encoder(enc)
+	if xe.Tokens.Depth() > startDetectingCyclesAfter {
+		v := reflect.ValueOf(arr)
+		if err := visitPointer(&xe.SeenPointers, v); err != nil {
+			return err
+		}
+		defer leavePointer(&xe.SeenPointers, v)
+	}
+
+	// Handle empty slices.
+	if len(arr) == 0 {
+		if mo.Flags.Get(jsonflags.FormatNilSliceAsNull) && arr == nil {
+			return enc.WriteToken(jsontext.Null)
+		}
+		// Optimize for marshaling an empty slice without any preceding whitespace.
+		if !xe.Flags.Get(jsonflags.Expand) && !xe.Tokens.Last.NeedObjectName() {
+			xe.Buf = append(xe.Tokens.MayAppendDelim(xe.Buf, '['), "[]"...)
+			xe.Tokens.Last.Increment()
+			if xe.NeedFlush() {
+				return xe.Flush()
+			}
+			return nil
+		}
+	}
+
+	if err := enc.WriteToken(jsontext.ArrayStart); err != nil {
+		return err
+	}
+	for _, val := range arr {
+		if err := marshalValueAny(enc, val, mo); err != nil {
+			return err
+		}
+	}
+	if err := enc.WriteToken(jsontext.ArrayEnd); err != nil {
+		return err
+	}
+	return nil
+}
+
+func unmarshalArrayAny(dec *jsontext.Decoder, uo *jsonopts.Struct) ([]any, error) {
+	tok, err := dec.ReadToken()
+	if err != nil {
+		return nil, err
+	}
+	k := tok.Kind()
+	switch k {
+	case 'n':
+		return nil, nil
+	case '[':
+		arr := []any{}
+		for dec.PeekKind() != ']' {
+			val, err := unmarshalValueAny(dec, uo)
+			arr = append(arr, val)
+			if err != nil {
+				return arr, err
+			}
+		}
+		if _, err := dec.ReadToken(); err != nil {
+			return arr, err
+		}
+		return arr, nil
+	}
+	return nil, &SemanticError{action: "unmarshal", JSONKind: k, GoType: sliceAnyType}
+}

vendor/github.com/go-json-experiment/json/arshal_funcs.go

@@ -0,0 +1,402 @@
+// 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 json
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"sync"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+// SkipFunc may be returned by [MarshalFuncV2] and [UnmarshalFuncV2] functions.
+//
+// Any function that returns SkipFunc must not cause observable side effects
+// on the provided [jsontext.Encoder] or [jsontext.Decoder].
+// For example, it is permissible to call [jsontext.Decoder.PeekKind],
+// but not permissible to call [jsontext.Decoder.ReadToken] or
+// [jsontext.Encoder.WriteToken] since such methods mutate the state.
+var SkipFunc = errors.New("json: skip function")
+
+// Marshalers is a list of functions that may override the marshal behavior
+// of specific types. Populate [WithMarshalers] to use it with
+// [Marshal], [MarshalWrite], or [MarshalEncode].
+// A nil *Marshalers is equivalent to an empty list.
+// There are no exported fields or methods on Marshalers.
+type Marshalers = typedMarshalers
+
+// NewMarshalers constructs a flattened list of marshal functions.
+// If multiple functions in the list are applicable for a value of a given type,
+// then those earlier in the list take precedence over those that come later.
+// If a function returns [SkipFunc], then the next applicable function is called,
+// otherwise the default marshaling behavior is used.
+//
+// For example:
+//
+//	m1 := NewMarshalers(f1, f2)
+//	m2 := NewMarshalers(f0, m1, f3)     // equivalent to m3
+//	m3 := NewMarshalers(f0, f1, f2, f3) // equivalent to m2
+func NewMarshalers(ms ...*Marshalers) *Marshalers {
+	return newMarshalers(ms...)
+}
+
+// Unmarshalers is a list of functions that may override the unmarshal behavior
+// of specific types. Populate [WithUnmarshalers] to use it with
+// [Unmarshal], [UnmarshalRead], or [UnmarshalDecode].
+// A nil *Unmarshalers is equivalent to an empty list.
+// There are no exported fields or methods on Unmarshalers.
+type Unmarshalers = typedUnmarshalers
+
+// NewUnmarshalers constructs a flattened list of unmarshal functions.
+// If multiple functions in the list are applicable for a value of a given type,
+// then those earlier in the list take precedence over those that come later.
+// If a function returns [SkipFunc], then the next applicable function is called,
+// otherwise the default unmarshaling behavior is used.
+//
+// For example:
+//
+//	u1 := NewUnmarshalers(f1, f2)
+//	u2 := NewUnmarshalers(f0, u1, f3)     // equivalent to u3
+//	u3 := NewUnmarshalers(f0, f1, f2, f3) // equivalent to u2
+func NewUnmarshalers(us ...*Unmarshalers) *Unmarshalers {
+	return newUnmarshalers(us...)
+}
+
+type typedMarshalers = typedArshalers[jsontext.Encoder]
+type typedUnmarshalers = typedArshalers[jsontext.Decoder]
+type typedArshalers[Coder any] struct {
+	nonComparable
+
+	fncVals  []typedArshaler[Coder]
+	fncCache sync.Map // map[reflect.Type]arshaler
+
+	// fromAny reports whether any of Go types used to represent arbitrary JSON
+	// (i.e., any, bool, string, float64, map[string]any, or []any) matches
+	// any of the provided type-specific arshalers.
+	//
+	// This bit of information is needed in arshal_default.go to determine
+	// whether to use the specialized logic in arshal_any.go to handle
+	// the any interface type. The logic in arshal_any.go does not support
+	// type-specific arshal functions, so we must avoid using that logic
+	// if this is true.
+	fromAny bool
+}
+type typedMarshaler = typedArshaler[jsontext.Encoder]
+type typedUnmarshaler = typedArshaler[jsontext.Decoder]
+type typedArshaler[Coder any] struct {
+	typ     reflect.Type
+	fnc     func(*Coder, addressableValue, *jsonopts.Struct) error
+	maySkip bool
+}
+
+func newMarshalers(ms ...*Marshalers) *Marshalers       { return newTypedArshalers(ms...) }
+func newUnmarshalers(us ...*Unmarshalers) *Unmarshalers { return newTypedArshalers(us...) }
+func newTypedArshalers[Coder any](as ...*typedArshalers[Coder]) *typedArshalers[Coder] {
+	var a typedArshalers[Coder]
+	for _, a2 := range as {
+		if a2 != nil {
+			a.fncVals = append(a.fncVals, a2.fncVals...)
+			a.fromAny = a.fromAny || a2.fromAny
+		}
+	}
+	if len(a.fncVals) == 0 {
+		return nil
+	}
+	return &a
+}
+
+func (a *typedArshalers[Coder]) lookup(fnc func(*Coder, addressableValue, *jsonopts.Struct) error, t reflect.Type) (func(*Coder, addressableValue, *jsonopts.Struct) error, bool) {
+	if a == nil {
+		return fnc, false
+	}
+	if v, ok := a.fncCache.Load(t); ok {
+		if v == nil {
+			return fnc, false
+		}
+		return v.(func(*Coder, addressableValue, *jsonopts.Struct) error), true
+	}
+
+	// Collect a list of arshalers that can be called for this type.
+	// This list may be longer than 1 since some arshalers can be skipped.
+	var fncs []func(*Coder, addressableValue, *jsonopts.Struct) error
+	for _, fncVal := range a.fncVals {
+		if !castableTo(t, fncVal.typ) {
+			continue
+		}
+		fncs = append(fncs, fncVal.fnc)
+		if !fncVal.maySkip {
+			break // subsequent arshalers will never be called
+		}
+	}
+
+	if len(fncs) == 0 {
+		a.fncCache.Store(t, nil) // nil to indicate that no funcs found
+		return fnc, false
+	}
+
+	// Construct an arshaler that may call every applicable arshaler.
+	fncDefault := fnc
+	fnc = func(c *Coder, v addressableValue, o *jsonopts.Struct) error {
+		for _, fnc := range fncs {
+			if err := fnc(c, v, o); err != SkipFunc {
+				return err // may be nil or non-nil
+			}
+		}
+		return fncDefault(c, v, o)
+	}
+
+	// Use the first stored so duplicate work can be garbage collected.
+	v, _ := a.fncCache.LoadOrStore(t, fnc)
+	return v.(func(*Coder, addressableValue, *jsonopts.Struct) error), true
+}
+
+// MarshalFuncV1 constructs a type-specific marshaler that
+// specifies how to marshal values of type T.
+// T can be any type except a named pointer.
+// The function is always provided with a non-nil pointer value
+// if T is an interface or pointer type.
+//
+// The function must marshal exactly one JSON value.
+// The value of T must not be retained outside the function call.
+// It may not return [SkipFunc].
+func MarshalFuncV1[T any](fn func(T) ([]byte, error)) *Marshalers {
+	t := reflect.TypeOf((*T)(nil)).Elem()
+	assertCastableTo(t, true)
+	typFnc := typedMarshaler{
+		typ: t,
+		fnc: func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			val, err := fn(va.castTo(t).Interface().(T))
+			if err != nil {
+				err = wrapSkipFunc(err, "marshal function of type func(T) ([]byte, error)")
+				// TODO: Avoid wrapping semantic errors.
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			if err := enc.WriteValue(val); err != nil {
+				// TODO: Avoid wrapping semantic or I/O errors.
+				return &SemanticError{action: "marshal", JSONKind: jsontext.Value(val).Kind(), GoType: t, Err: err}
+			}
+			return nil
+		},
+	}
+	return &Marshalers{fncVals: []typedMarshaler{typFnc}, fromAny: castableToFromAny(t)}
+}
+
+// MarshalFuncV2 constructs a type-specific marshaler that
+// specifies how to marshal values of type T.
+// T can be any type except a named pointer.
+// The function is always provided with a non-nil pointer value
+// if T is an interface or pointer type.
+//
+// The function must marshal exactly one JSON value by calling write methods
+// on the provided encoder. It may return [SkipFunc] such that marshaling can
+// move on to the next marshal function. However, no mutable method calls may
+// be called on the encoder if [SkipFunc] is returned.
+// The pointer to [jsontext.Encoder], the value of T, and the [Options] value
+// must not be retained outside the function call.
+func MarshalFuncV2[T any](fn func(*jsontext.Encoder, T, Options) error) *Marshalers {
+	t := reflect.TypeOf((*T)(nil)).Elem()
+	assertCastableTo(t, true)
+	typFnc := typedMarshaler{
+		typ: t,
+		fnc: func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			xe := export.Encoder(enc)
+			prevDepth, prevLength := xe.Tokens.DepthLength()
+			xe.Flags.Set(jsonflags.WithinArshalCall | 1)
+			err := fn(enc, va.castTo(t).Interface().(T), mo)
+			xe.Flags.Set(jsonflags.WithinArshalCall | 0)
+			currDepth, currLength := xe.Tokens.DepthLength()
+			if err == nil && (prevDepth != currDepth || prevLength+1 != currLength) {
+				err = errors.New("must write exactly one JSON value")
+			}
+			if err != nil {
+				if err == SkipFunc {
+					if prevDepth == currDepth && prevLength == currLength {
+						return SkipFunc
+					}
+					err = errors.New("must not write any JSON tokens when skipping")
+				}
+				// TODO: Avoid wrapping semantic or I/O errors.
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			return nil
+		},
+		maySkip: true,
+	}
+	return &Marshalers{fncVals: []typedMarshaler{typFnc}, fromAny: castableToFromAny(t)}
+}
+
+// UnmarshalFuncV1 constructs a type-specific unmarshaler that
+// specifies how to unmarshal values of type T.
+// T must be an unnamed pointer or an interface type.
+// The function is always provided with a non-nil pointer value.
+//
+// The function must unmarshal exactly one JSON value.
+// The input []byte must not be mutated.
+// The input []byte and value T must not be retained outside the function call.
+// It may not return [SkipFunc].
+func UnmarshalFuncV1[T any](fn func([]byte, T) error) *Unmarshalers {
+	t := reflect.TypeOf((*T)(nil)).Elem()
+	assertCastableTo(t, false)
+	typFnc := typedUnmarshaler{
+		typ: t,
+		fnc: func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			val, err := dec.ReadValue()
+			if err != nil {
+				return err // must be a syntactic or I/O error
+			}
+			err = fn(val, va.castTo(t).Interface().(T))
+			if err != nil {
+				err = wrapSkipFunc(err, "unmarshal function of type func([]byte, T) error")
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				return &SemanticError{action: "unmarshal", JSONKind: val.Kind(), GoType: t, Err: err}
+			}
+			return nil
+		},
+	}
+	return &Unmarshalers{fncVals: []typedUnmarshaler{typFnc}, fromAny: castableToFromAny(t)}
+}
+
+// UnmarshalFuncV2 constructs a type-specific unmarshaler that
+// specifies how to unmarshal values of type T.
+// T must be an unnamed pointer or an interface type.
+// The function is always provided with a non-nil pointer value.
+//
+// The function must unmarshal exactly one JSON value by calling read methods
+// on the provided decoder. It may return [SkipFunc] such that unmarshaling can
+// move on to the next unmarshal function. However, no mutable method calls may
+// be called on the decoder if [SkipFunc] is returned.
+// The pointer to [jsontext.Decoder], the value of T, and [Options] value
+// must not be retained outside the function call.
+func UnmarshalFuncV2[T any](fn func(*jsontext.Decoder, T, Options) error) *Unmarshalers {
+	t := reflect.TypeOf((*T)(nil)).Elem()
+	assertCastableTo(t, false)
+	typFnc := typedUnmarshaler{
+		typ: t,
+		fnc: func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			xd := export.Decoder(dec)
+			prevDepth, prevLength := xd.Tokens.DepthLength()
+			xd.Flags.Set(jsonflags.WithinArshalCall | 1)
+			err := fn(dec, va.castTo(t).Interface().(T), uo)
+			xd.Flags.Set(jsonflags.WithinArshalCall | 0)
+			currDepth, currLength := xd.Tokens.DepthLength()
+			if err == nil && (prevDepth != currDepth || prevLength+1 != currLength) {
+				err = errors.New("must read exactly one JSON value")
+			}
+			if err != nil {
+				if err == SkipFunc {
+					if prevDepth == currDepth && prevLength == currLength {
+						return SkipFunc
+					}
+					err = errors.New("must not read any JSON tokens when skipping")
+				}
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				return &SemanticError{action: "unmarshal", GoType: t, Err: err}
+			}
+			return nil
+		},
+		maySkip: true,
+	}
+	return &Unmarshalers{fncVals: []typedUnmarshaler{typFnc}, fromAny: castableToFromAny(t)}
+}
+
+// assertCastableTo asserts that "to" is a valid type to be casted to.
+// These are the Go types that type-specific arshalers may operate upon.
+//
+// Let AllTypes be the universal set of all possible Go types.
+// This function generally asserts that:
+//
+//	len([from for from in AllTypes if castableTo(from, to)]) > 0
+//
+// otherwise it panics.
+//
+// As a special-case if marshal is false, then we forbid any non-pointer or
+// non-interface type since it is almost always a bug trying to unmarshal
+// into something where the end-user caller did not pass in an addressable value
+// since they will not observe the mutations.
+func assertCastableTo(to reflect.Type, marshal bool) {
+	switch to.Kind() {
+	case reflect.Interface:
+		return
+	case reflect.Pointer:
+		// Only allow unnamed pointers to be consistent with the fact that
+		// taking the address of a value produces an unnamed pointer type.
+		if to.Name() == "" {
+			return
+		}
+	default:
+		// Technically, non-pointer types are permissible for unmarshal.
+		// However, they are often a bug since the receiver would be immutable.
+		// Thus, only allow them for marshaling.
+		if marshal {
+			return
+		}
+	}
+	if marshal {
+		panic(fmt.Sprintf("input type %v must be an interface type, an unnamed pointer type, or a non-pointer type", to))
+	} else {
+		panic(fmt.Sprintf("input type %v must be an interface type or an unnamed pointer type", to))
+	}
+}
+
+// castableTo checks whether values of type "from" can be casted to type "to".
+// Nil pointer or interface "from" values are never considered castable.
+//
+// This function must be kept in sync with addressableValue.castTo.
+func castableTo(from, to reflect.Type) bool {
+	switch to.Kind() {
+	case reflect.Interface:
+		// TODO: This breaks when ordinary interfaces can have type sets
+		// since interfaces now exist where only the value form of a type (T)
+		// implements the interface, but not the pointer variant (*T).
+		// See https://go.dev/issue/45346.
+		return reflect.PointerTo(from).Implements(to)
+	case reflect.Pointer:
+		// Common case for unmarshaling.
+		// From must be a concrete or interface type.
+		return reflect.PointerTo(from) == to
+	default:
+		// Common case for marshaling.
+		// From must be a concrete type.
+		return from == to
+	}
+}
+
+// castTo casts va to the specified type.
+// If the type is an interface, then the underlying type will always
+// be a non-nil pointer to a concrete type.
+//
+// Requirement: castableTo(va.Type(), to) must hold.
+func (va addressableValue) castTo(to reflect.Type) reflect.Value {
+	switch to.Kind() {
+	case reflect.Interface:
+		return va.Addr().Convert(to)
+	case reflect.Pointer:
+		return va.Addr()
+	default:
+		return va.Value
+	}
+}
+
+// castableToFromAny reports whether "to" can be casted to from any
+// of the dynamic types used to represent arbitrary JSON.
+func castableToFromAny(to reflect.Type) bool {
+	for _, from := range []reflect.Type{anyType, boolType, stringType, float64Type, mapStringAnyType, sliceAnyType} {
+		if castableTo(from, to) {
+			return true
+		}
+	}
+	return false
+}
+
+func wrapSkipFunc(err error, what string) error {
+	if err == SkipFunc {
+		return errors.New(what + " cannot be skipped")
+	}
+	return err
+}

vendor/github.com/go-json-experiment/json/arshal_inlined.go

@@ -0,0 +1,226 @@
+// 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 json
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"reflect"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+// This package supports "inlining" a Go struct field, where the contents
+// of the serialized field (which must be a JSON object) are treated as if
+// they are part of the parent Go struct (which represents a JSON object).
+//
+// Generally, inlined fields are of a Go struct type, where the fields of the
+// nested struct are virtually hoisted up to the parent struct using rules
+// similar to how Go embedding works (but operating within the JSON namespace).
+//
+// However, inlined fields may also be of a Go map type with a string key or
+// a jsontext.Value. Such inlined fields are called "fallback" fields since they
+// represent any arbitrary JSON object member. Explicitly named fields take
+// precedence over the inlined fallback. Only one inlined fallback is allowed.
+
+var jsontextValueType = reflect.TypeOf((*jsontext.Value)(nil)).Elem()
+
+// marshalInlinedFallbackAll marshals all the members in an inlined fallback.
+func marshalInlinedFallbackAll(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct, f *structField, insertUnquotedName func([]byte) bool) error {
+	v := addressableValue{va.Field(f.index[0])} // addressable if struct value is addressable
+	if len(f.index) > 1 {
+		v = v.fieldByIndex(f.index[1:], false)
+		if !v.IsValid() {
+			return nil // implies a nil inlined field
+		}
+	}
+	v = v.indirect(false)
+	if !v.IsValid() {
+		return nil
+	}
+
+	if v.Type() == jsontextValueType {
+		// TODO(https://go.dev/issue/62121): Use reflect.Value.AssertTo.
+		b := *v.Addr().Interface().(*jsontext.Value)
+		if len(b) == 0 { // TODO: Should this be nil? What if it were all whitespace?
+			return nil
+		}
+
+		dec := export.GetBufferedDecoder(b)
+		defer export.PutBufferedDecoder(dec)
+		xd := export.Decoder(dec)
+		xd.Flags.Set(jsonflags.AllowDuplicateNames | jsonflags.AllowInvalidUTF8 | 1)
+
+		tok, err := dec.ReadToken()
+		if err != nil {
+			if err == io.EOF {
+				err = io.ErrUnexpectedEOF
+			}
+			return &SemanticError{action: "marshal", GoType: jsontextValueType, Err: err}
+		}
+		if tok.Kind() != '{' {
+			err := errors.New("inlined raw value must be a JSON object")
+			return &SemanticError{action: "marshal", JSONKind: tok.Kind(), GoType: jsontextValueType, Err: err}
+		}
+		for dec.PeekKind() != '}' {
+			// Parse the JSON object name.
+			var flags jsonwire.ValueFlags
+			val, err := xd.ReadValue(&flags)
+			if err != nil {
+				return &SemanticError{action: "marshal", GoType: jsontextValueType, Err: err}
+			}
+			if insertUnquotedName != nil {
+				name := jsonwire.UnquoteMayCopy(val, flags.IsVerbatim())
+				if !insertUnquotedName(name) {
+					return export.NewDuplicateNameError(val, 0)
+				}
+			}
+			if err := enc.WriteValue(val); err != nil {
+				return err
+			}
+
+			// Parse the JSON object value.
+			val, err = xd.ReadValue(&flags)
+			if err != nil {
+				return &SemanticError{action: "marshal", GoType: jsontextValueType, Err: err}
+			}
+			if err := enc.WriteValue(val); err != nil {
+				return err
+			}
+		}
+		if _, err := dec.ReadToken(); err != nil {
+			return &SemanticError{action: "marshal", GoType: jsontextValueType, Err: err}
+		}
+		if err := xd.CheckEOF(); err != nil {
+			return &SemanticError{action: "marshal", GoType: jsontextValueType, Err: err}
+		}
+		return nil
+	} else {
+		m := v // must be a map[string]V
+		n := m.Len()
+		if n == 0 {
+			return nil
+		}
+		mk := newAddressableValue(stringType)
+		mv := newAddressableValue(m.Type().Elem())
+		marshalKey := func(mk addressableValue) error {
+			xe := export.Encoder(enc)
+			b, err := jsonwire.AppendQuote(enc.UnusedBuffer(), mk.String(), &xe.Flags)
+			if err != nil {
+				return err
+			}
+			if insertUnquotedName != nil {
+				isVerbatim := bytes.IndexByte(b, '\\') < 0
+				name := jsonwire.UnquoteMayCopy(b, isVerbatim)
+				if !insertUnquotedName(name) {
+					return export.NewDuplicateNameError(b, 0)
+				}
+			}
+			return enc.WriteValue(b)
+		}
+		marshalVal := f.fncs.marshal
+		if mo.Marshalers != nil {
+			marshalVal, _ = mo.Marshalers.(*Marshalers).lookup(marshalVal, mv.Type())
+		}
+		if !mo.Flags.Get(jsonflags.Deterministic) || n <= 1 {
+			for iter := m.MapRange(); iter.Next(); {
+				mk.SetIterKey(iter)
+				if err := marshalKey(mk); err != nil {
+					return err
+				}
+				mv.Set(iter.Value())
+				if err := marshalVal(enc, mv, mo); err != nil {
+					return err
+				}
+			}
+		} else {
+			names := getStrings(n)
+			for i, iter := 0, m.Value.MapRange(); i < n && iter.Next(); i++ {
+				mk.SetIterKey(iter)
+				(*names)[i] = mk.String()
+			}
+			names.Sort()
+			for _, name := range *names {
+				mk.SetString(name)
+				if err := marshalKey(mk); err != nil {
+					return err
+				}
+				// TODO(https://go.dev/issue/57061): Use mv.SetMapIndexOf.
+				mv.Set(m.MapIndex(mk.Value))
+				if err := marshalVal(enc, mv, mo); err != nil {
+					return err
+				}
+			}
+			putStrings(names)
+		}
+		return nil
+	}
+}
+
+// unmarshalInlinedFallbackNext unmarshals only the next member in an inlined fallback.
+func unmarshalInlinedFallbackNext(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct, f *structField, quotedName, unquotedName []byte) error {
+	v := addressableValue{va.Field(f.index[0])} // addressable if struct value is addressable
+	if len(f.index) > 1 {
+		v = v.fieldByIndex(f.index[1:], true)
+	}
+	v = v.indirect(true)
+
+	if v.Type() == jsontextValueType {
+		b := v.Addr().Interface().(*jsontext.Value)
+		if len(*b) == 0 { // TODO: Should this be nil? What if it were all whitespace?
+			*b = append(*b, '{')
+		} else {
+			*b = jsonwire.TrimSuffixWhitespace(*b)
+			if jsonwire.HasSuffixByte(*b, '}') {
+				// TODO: When merging into an object for the first time,
+				// should we verify that it is valid?
+				*b = jsonwire.TrimSuffixByte(*b, '}')
+				*b = jsonwire.TrimSuffixWhitespace(*b)
+				if !jsonwire.HasSuffixByte(*b, ',') && !jsonwire.HasSuffixByte(*b, '{') {
+					*b = append(*b, ',')
+				}
+			} else {
+				err := errors.New("inlined raw value must be a JSON object")
+				return &SemanticError{action: "unmarshal", GoType: jsontextValueType, Err: err}
+			}
+		}
+		*b = append(*b, quotedName...)
+		*b = append(*b, ':')
+		val, err := dec.ReadValue()
+		if err != nil {
+			return err
+		}
+		*b = append(*b, val...)
+		*b = append(*b, '}')
+		return nil
+	} else {
+		name := string(unquotedName) // TODO: Intern this?
+
+		m := v // must be a map[string]V
+		if m.IsNil() {
+			m.Set(reflect.MakeMap(m.Type()))
+		}
+		mk := reflect.ValueOf(name)
+		mv := newAddressableValue(v.Type().Elem()) // TODO: Cache across calls?
+		if v2 := m.MapIndex(mk); v2.IsValid() {
+			mv.Set(v2)
+		}
+
+		unmarshal := f.fncs.unmarshal
+		if uo.Unmarshalers != nil {
+			unmarshal, _ = uo.Unmarshalers.(*Unmarshalers).lookup(unmarshal, mv.Type())
+		}
+		err := unmarshal(dec, mv, uo)
+		m.SetMapIndex(mk, mv.Value)
+		if err != nil {
+			return err
+		}
+		return nil
+	}
+}

vendor/github.com/go-json-experiment/json/arshal_methods.go

@@ -0,0 +1,259 @@
+// 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 json
+
+import (
+	"encoding"
+	"errors"
+	"reflect"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+// Interfaces for custom serialization.
+var (
+	jsonMarshalerV1Type   = reflect.TypeOf((*MarshalerV1)(nil)).Elem()
+	jsonMarshalerV2Type   = reflect.TypeOf((*MarshalerV2)(nil)).Elem()
+	jsonUnmarshalerV1Type = reflect.TypeOf((*UnmarshalerV1)(nil)).Elem()
+	jsonUnmarshalerV2Type = reflect.TypeOf((*UnmarshalerV2)(nil)).Elem()
+	textAppenderType      = reflect.TypeOf((*encodingTextAppender)(nil)).Elem()
+	textMarshalerType     = reflect.TypeOf((*encoding.TextMarshaler)(nil)).Elem()
+	textUnmarshalerType   = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+
+	// TODO(https://go.dev/issue/62384): Use encoding.TextAppender instead of this hack.
+	// This exists for now to provide performance benefits to netip types.
+	// There is no semantic difference with this change.
+	appenderToType = reflect.TypeOf((*interface{ AppendTo([]byte) []byte })(nil)).Elem()
+)
+
+// TODO(https://go.dev/issue/62384): Use encoding.TextAppender instead
+// and document public support for this method in json.Marshal.
+type encodingTextAppender interface {
+	AppendText(b []byte) ([]byte, error)
+}
+
+// MarshalerV1 is implemented by types that can marshal themselves.
+// It is recommended that types implement [MarshalerV2] unless the implementation
+// is trying to avoid a hard dependency on the "jsontext" package.
+//
+// It is recommended that implementations return a buffer that is safe
+// for the caller to retain and potentially mutate.
+type MarshalerV1 interface {
+	MarshalJSON() ([]byte, error)
+}
+
+// MarshalerV2 is implemented by types that can marshal themselves.
+// It is recommended that types implement MarshalerV2 instead of [MarshalerV1]
+// since this is both more performant and flexible.
+// If a type implements both MarshalerV1 and MarshalerV2,
+// then MarshalerV2 takes precedence. In such a case, both implementations
+// should aim to have equivalent behavior for the default marshal options.
+//
+// The implementation must write only one JSON value to the Encoder and
+// must not retain the pointer to [jsontext.Encoder] or the [Options] value.
+type MarshalerV2 interface {
+	MarshalJSONV2(*jsontext.Encoder, Options) error
+
+	// TODO: Should users call the MarshalEncode function or
+	// should/can they call this method directly? Does it matter?
+}
+
+// UnmarshalerV1 is implemented by types that can unmarshal themselves.
+// It is recommended that types implement [UnmarshalerV2] unless the implementation
+// is trying to avoid a hard dependency on the "jsontext" package.
+//
+// The input can be assumed to be a valid encoding of a JSON value
+// if called from unmarshal functionality in this package.
+// UnmarshalJSON must copy the JSON data if it is retained after returning.
+// It is recommended that UnmarshalJSON implement merge semantics when
+// unmarshaling into a pre-populated value.
+//
+// Implementations must not retain or mutate the input []byte.
+type UnmarshalerV1 interface {
+	UnmarshalJSON([]byte) error
+}
+
+// UnmarshalerV2 is implemented by types that can unmarshal themselves.
+// It is recommended that types implement UnmarshalerV2 instead of [UnmarshalerV1]
+// since this is both more performant and flexible.
+// If a type implements both UnmarshalerV1 and UnmarshalerV2,
+// then UnmarshalerV2 takes precedence. In such a case, both implementations
+// should aim to have equivalent behavior for the default unmarshal options.
+//
+// The implementation must read only one JSON value from the Decoder.
+// It is recommended that UnmarshalJSONV2 implement merge semantics when
+// unmarshaling into a pre-populated value.
+//
+// Implementations must not retain the pointer to [jsontext.Decoder] or
+// the [Options] value.
+type UnmarshalerV2 interface {
+	UnmarshalJSONV2(*jsontext.Decoder, Options) error
+
+	// TODO: Should users call the UnmarshalDecode function or
+	// should/can they call this method directly? Does it matter?
+}
+
+func makeMethodArshaler(fncs *arshaler, t reflect.Type) *arshaler {
+	// Avoid injecting method arshaler on the pointer or interface version
+	// to avoid ever calling the method on a nil pointer or interface receiver.
+	// Let it be injected on the value receiver (which is always addressable).
+	if t.Kind() == reflect.Pointer || t.Kind() == reflect.Interface {
+		return fncs
+	}
+
+	// Handle custom marshaler.
+	switch which := implementsWhich(t, jsonMarshalerV2Type, jsonMarshalerV1Type, textAppenderType, textMarshalerType); which {
+	case jsonMarshalerV2Type:
+		fncs.nonDefault = true
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			xe := export.Encoder(enc)
+			prevDepth, prevLength := xe.Tokens.DepthLength()
+			xe.Flags.Set(jsonflags.WithinArshalCall | 1)
+			err := va.Addr().Interface().(MarshalerV2).MarshalJSONV2(enc, mo)
+			xe.Flags.Set(jsonflags.WithinArshalCall | 0)
+			currDepth, currLength := xe.Tokens.DepthLength()
+			if (prevDepth != currDepth || prevLength+1 != currLength) && err == nil {
+				err = errors.New("must write exactly one JSON value")
+			}
+			if err != nil {
+				err = wrapSkipFunc(err, "marshal method")
+				// TODO: Avoid wrapping semantic or I/O errors.
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			return nil
+		}
+	case jsonMarshalerV1Type:
+		fncs.nonDefault = true
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			marshaler := va.Addr().Interface().(MarshalerV1)
+			val, err := marshaler.MarshalJSON()
+			if err != nil {
+				err = wrapSkipFunc(err, "marshal method")
+				// TODO: Avoid wrapping semantic errors.
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			if err := enc.WriteValue(val); err != nil {
+				// TODO: Avoid wrapping semantic or I/O errors.
+				return &SemanticError{action: "marshal", JSONKind: jsontext.Value(val).Kind(), GoType: t, Err: err}
+			}
+			return nil
+		}
+	case textAppenderType:
+		fncs.nonDefault = true
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) (err error) {
+			appender := va.Addr().Interface().(encodingTextAppender)
+			if err := export.Encoder(enc).AppendRaw('"', false, appender.AppendText); err != nil {
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				err = wrapSkipFunc(err, "append method")
+				return &SemanticError{action: "marshal", JSONKind: '"', GoType: t, Err: err}
+			}
+			return nil
+		}
+	case textMarshalerType:
+		fncs.nonDefault = true
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			marshaler := va.Addr().Interface().(encoding.TextMarshaler)
+			if err := export.Encoder(enc).AppendRaw('"', false, func(b []byte) ([]byte, error) {
+				b2, err := marshaler.MarshalText()
+				return append(b, b2...), err
+			}); err != nil {
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				err = wrapSkipFunc(err, "marshal method")
+				return &SemanticError{action: "marshal", JSONKind: '"', GoType: t, Err: err}
+			}
+			return nil
+		}
+		// TODO(https://go.dev/issue/62384): Rely on encoding.TextAppender instead.
+		if implementsWhich(t, appenderToType) != nil && t.PkgPath() == "net/netip" {
+			fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+				appender := va.Addr().Interface().(interface{ AppendTo([]byte) []byte })
+				if err := export.Encoder(enc).AppendRaw('"', false, func(b []byte) ([]byte, error) {
+					return appender.AppendTo(b), nil
+				}); err != nil {
+					// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+					err = wrapSkipFunc(err, "append method")
+					return &SemanticError{action: "marshal", JSONKind: '"', GoType: t, Err: err}
+				}
+				return nil
+			}
+		}
+	}
+
+	// Handle custom unmarshaler.
+	switch which := implementsWhich(t, jsonUnmarshalerV2Type, jsonUnmarshalerV1Type, textUnmarshalerType); which {
+	case jsonUnmarshalerV2Type:
+		fncs.nonDefault = true
+		fncs.unmarshal = func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			xd := export.Decoder(dec)
+			prevDepth, prevLength := xd.Tokens.DepthLength()
+			xd.Flags.Set(jsonflags.WithinArshalCall | 1)
+			err := va.Addr().Interface().(UnmarshalerV2).UnmarshalJSONV2(dec, uo)
+			xd.Flags.Set(jsonflags.WithinArshalCall | 0)
+			currDepth, currLength := xd.Tokens.DepthLength()
+			if (prevDepth != currDepth || prevLength+1 != currLength) && err == nil {
+				err = errors.New("must read exactly one JSON value")
+			}
+			if err != nil {
+				err = wrapSkipFunc(err, "unmarshal method")
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				return &SemanticError{action: "unmarshal", GoType: t, Err: err}
+			}
+			return nil
+		}
+	case jsonUnmarshalerV1Type:
+		fncs.nonDefault = true
+		fncs.unmarshal = func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			val, err := dec.ReadValue()
+			if err != nil {
+				return err // must be a syntactic or I/O error
+			}
+			unmarshaler := va.Addr().Interface().(UnmarshalerV1)
+			if err := unmarshaler.UnmarshalJSON(val); err != nil {
+				err = wrapSkipFunc(err, "unmarshal method")
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				return &SemanticError{action: "unmarshal", JSONKind: val.Kind(), GoType: t, Err: err}
+			}
+			return nil
+		}
+	case textUnmarshalerType:
+		fncs.nonDefault = true
+		fncs.unmarshal = func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			xd := export.Decoder(dec)
+			var flags jsonwire.ValueFlags
+			val, err := xd.ReadValue(&flags)
+			if err != nil {
+				return err // must be a syntactic or I/O error
+			}
+			if val.Kind() != '"' {
+				err = errors.New("JSON value must be string type")
+				return &SemanticError{action: "unmarshal", JSONKind: val.Kind(), GoType: t, Err: err}
+			}
+			s := jsonwire.UnquoteMayCopy(val, flags.IsVerbatim())
+			unmarshaler := va.Addr().Interface().(encoding.TextUnmarshaler)
+			if err := unmarshaler.UnmarshalText(s); err != nil {
+				err = wrapSkipFunc(err, "unmarshal method")
+				// TODO: Avoid wrapping semantic, syntactic, or I/O errors.
+				return &SemanticError{action: "unmarshal", JSONKind: val.Kind(), GoType: t, Err: err}
+			}
+			return nil
+		}
+	}
+
+	return fncs
+}
+
+// implementsWhich is like t.Implements(ifaceType) for a list of interfaces,
+// but checks whether either t or reflect.PointerTo(t) implements the interface.
+func implementsWhich(t reflect.Type, ifaceTypes ...reflect.Type) (which reflect.Type) {
+	for _, ifaceType := range ifaceTypes {
+		if t.Implements(ifaceType) || reflect.PointerTo(t).Implements(ifaceType) {
+			return ifaceType
+		}
+	}
+	return nil
+}

vendor/github.com/go-json-experiment/json/arshal_time.go

@@ -0,0 +1,621 @@
+// 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 json
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"math"
+	"math/bits"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+var (
+	timeDurationType = reflect.TypeOf((*time.Duration)(nil)).Elem()
+	timeTimeType     = reflect.TypeOf((*time.Time)(nil)).Elem()
+)
+
+func makeTimeArshaler(fncs *arshaler, t reflect.Type) *arshaler {
+	// Ideally, time types would implement MarshalerV2 and UnmarshalerV2,
+	// but that would incur a dependency on package json from package time.
+	// Given how widely used time is, it is more acceptable that we incur a
+	// dependency on time from json.
+	//
+	// Injecting the arshaling functionality like this will not be identical
+	// to actually declaring methods on the time types since embedding of the
+	// time types will not be able to forward this functionality.
+	switch t {
+	case timeDurationType:
+		fncs.nonDefault = true
+		marshalNano := fncs.marshal
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) error {
+			xe := export.Encoder(enc)
+			var m durationArshaler
+			if mo.Format != "" && mo.FormatDepth == xe.Tokens.Depth() {
+				if !m.initFormat(mo.Format) {
+					return newInvalidFormatError("marshal", t, mo.Format)
+				}
+			} else if mo.Flags.Get(jsonflags.FormatTimeDurationAsNanosecond) {
+				return marshalNano(enc, va, mo)
+			}
+
+			// TODO(https://go.dev/issue/62121): Use reflect.Value.AssertTo.
+			m.td = *va.Addr().Interface().(*time.Duration)
+			k := stringOrNumberKind(!m.isNumeric() || mo.Flags.Get(jsonflags.StringifyNumbers))
+			if err := xe.AppendRaw(k, true, m.appendMarshal); err != nil {
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			return nil
+		}
+		unmarshalNano := fncs.unmarshal
+		fncs.unmarshal = func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) error {
+			xd := export.Decoder(dec)
+			var u durationArshaler
+			if uo.Format != "" && uo.FormatDepth == xd.Tokens.Depth() {
+				if !u.initFormat(uo.Format) {
+					return newInvalidFormatError("unmarshal", t, uo.Format)
+				}
+			} else if uo.Flags.Get(jsonflags.FormatTimeDurationAsNanosecond) {
+				return unmarshalNano(dec, va, uo)
+			}
+
+			var flags jsonwire.ValueFlags
+			td := va.Addr().Interface().(*time.Duration)
+			val, err := xd.ReadValue(&flags)
+			if err != nil {
+				return err
+			}
+			switch k := val.Kind(); k {
+			case 'n':
+				*td = time.Duration(0)
+				return nil
+			case '"':
+				if u.isNumeric() && !uo.Flags.Get(jsonflags.StringifyNumbers) {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+				}
+				val = jsonwire.UnquoteMayCopy(val, flags.IsVerbatim())
+				if err := u.unmarshal(val); err != nil {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t, Err: err}
+				}
+				*td = u.td
+				return nil
+			case '0':
+				if !u.isNumeric() {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+				}
+				if err := u.unmarshal(val); err != nil {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t, Err: err}
+				}
+				*td = u.td
+				return nil
+			default:
+				return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+			}
+		}
+	case timeTimeType:
+		fncs.nonDefault = true
+		fncs.marshal = func(enc *jsontext.Encoder, va addressableValue, mo *jsonopts.Struct) (err error) {
+			xe := export.Encoder(enc)
+			var m timeArshaler
+			if mo.Format != "" && mo.FormatDepth == xe.Tokens.Depth() {
+				if !m.initFormat(mo.Format) {
+					return newInvalidFormatError("marshal", t, mo.Format)
+				}
+			}
+
+			// TODO(https://go.dev/issue/62121): Use reflect.Value.AssertTo.
+			m.tt = *va.Addr().Interface().(*time.Time)
+			k := stringOrNumberKind(!m.isNumeric() || mo.Flags.Get(jsonflags.StringifyNumbers))
+			if err := xe.AppendRaw(k, !m.hasCustomFormat(), m.appendMarshal); err != nil {
+				return &SemanticError{action: "marshal", GoType: t, Err: err}
+			}
+			return nil
+		}
+		fncs.unmarshal = func(dec *jsontext.Decoder, va addressableValue, uo *jsonopts.Struct) (err error) {
+			xd := export.Decoder(dec)
+			var u timeArshaler
+			if uo.Format != "" && uo.FormatDepth == xd.Tokens.Depth() {
+				if !u.initFormat(uo.Format) {
+					return newInvalidFormatError("unmarshal", t, uo.Format)
+				}
+			}
+
+			var flags jsonwire.ValueFlags
+			tt := va.Addr().Interface().(*time.Time)
+			val, err := xd.ReadValue(&flags)
+			if err != nil {
+				return err
+			}
+			switch k := val.Kind(); k {
+			case 'n':
+				*tt = time.Time{}
+				return nil
+			case '"':
+				if u.isNumeric() && !uo.Flags.Get(jsonflags.StringifyNumbers) {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+				}
+				val = jsonwire.UnquoteMayCopy(val, flags.IsVerbatim())
+				if err := u.unmarshal(val); err != nil {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t, Err: err}
+				}
+				*tt = u.tt
+				return nil
+			case '0':
+				if !u.isNumeric() {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+				}
+				if err := u.unmarshal(val); err != nil {
+					return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t, Err: err}
+				}
+				*tt = u.tt
+				return nil
+			default:
+				return &SemanticError{action: "unmarshal", JSONKind: k, GoType: t}
+			}
+		}
+	}
+	return fncs
+}
+
+type durationArshaler struct {
+	td time.Duration
+
+	// base records the representation where:
+	//   - 0 uses time.Duration.String
+	//   - 1e0, 1e3, 1e6, or 1e9 use a decimal encoding of the duration as
+	//     nanoseconds, microseconds, milliseconds, or seconds.
+	//   - 60 uses a "H:MM:SS.SSSSSSSSS" encoding
+	base uint
+}
+
+func (a *durationArshaler) initFormat(format string) (ok bool) {
+	switch format {
+	case "units":
+		a.base = 0
+	case "sec":
+		a.base = 1e9
+	case "milli":
+		a.base = 1e6
+	case "micro":
+		a.base = 1e3
+	case "nano":
+		a.base = 1e0
+	case "base60": // see https://en.wikipedia.org/wiki/Sexagesimal#Modern_usage
+		a.base = 60
+	default:
+		return false
+	}
+	return true
+}
+
+func (a *durationArshaler) isNumeric() bool {
+	return a.base != 0 && a.base != 60
+}
+
+func (a *durationArshaler) appendMarshal(b []byte) ([]byte, error) {
+	switch a.base {
+	case 0:
+		return append(b, a.td.String()...), nil
+	case 60:
+		return appendDurationBase60(b, a.td), nil
+	default:
+		return appendDurationBase10(b, a.td, a.base), nil
+	}
+}
+
+func (a *durationArshaler) unmarshal(b []byte) (err error) {
+	switch a.base {
+	case 0:
+		a.td, err = time.ParseDuration(string(b))
+	case 60:
+		a.td, err = parseDurationBase60(b)
+	default:
+		a.td, err = parseDurationBase10(b, a.base)
+	}
+	return err
+}
+
+type timeArshaler struct {
+	tt time.Time
+
+	// base records the representation where:
+	//   - 0 uses RFC 3339 encoding of the timestamp
+	//   - 1e0, 1e3, 1e6, or 1e9 use a decimal encoding of the timestamp as
+	//     seconds, milliseconds, microseconds, or nanoseconds since Unix epoch.
+	//   - math.MaxUint uses time.Time.Format to encode the timestamp
+	base   uint
+	format string // time format passed to time.Parse
+}
+
+func (a *timeArshaler) initFormat(format string) bool {
+	// We assume that an exported constant in the time package will
+	// always start with an uppercase ASCII letter.
+	if len(format) == 0 {
+		return false
+	}
+	a.base = math.MaxUint // implies custom format
+	if c := format[0]; !('a' <= c && c <= 'z') && !('A' <= c && c <= 'Z') {
+		a.format = format
+		return true
+	}
+	switch format {
+	case "ANSIC":
+		a.format = time.ANSIC
+	case "UnixDate":
+		a.format = time.UnixDate
+	case "RubyDate":
+		a.format = time.RubyDate
+	case "RFC822":
+		a.format = time.RFC822
+	case "RFC822Z":
+		a.format = time.RFC822Z
+	case "RFC850":
+		a.format = time.RFC850
+	case "RFC1123":
+		a.format = time.RFC1123
+	case "RFC1123Z":
+		a.format = time.RFC1123Z
+	case "RFC3339":
+		a.base = 0
+		a.format = time.RFC3339
+	case "RFC3339Nano":
+		a.base = 0
+		a.format = time.RFC3339Nano
+	case "Kitchen":
+		a.format = time.Kitchen
+	case "Stamp":
+		a.format = time.Stamp
+	case "StampMilli":
+		a.format = time.StampMilli
+	case "StampMicro":
+		a.format = time.StampMicro
+	case "StampNano":
+		a.format = time.StampNano
+	case "DateTime":
+		a.format = time.DateTime
+	case "DateOnly":
+		a.format = time.DateOnly
+	case "TimeOnly":
+		a.format = time.TimeOnly
+	case "unix":
+		a.base = 1e0
+	case "unixmilli":
+		a.base = 1e3
+	case "unixmicro":
+		a.base = 1e6
+	case "unixnano":
+		a.base = 1e9
+	default:
+		// Reject any Go identifier in case new constants are supported.
+		if strings.TrimFunc(format, isLetterOrDigit) == "" {
+			return false
+		}
+		a.format = format
+	}
+	return true
+}
+
+func (a *timeArshaler) isNumeric() bool {
+	return int(a.base) > 0
+}
+
+func (a *timeArshaler) hasCustomFormat() bool {
+	return a.base == math.MaxUint
+}
+
+func (a *timeArshaler) appendMarshal(b []byte) ([]byte, error) {
+	switch a.base {
+	case 0:
+		// TODO(https://go.dev/issue/60204): Use cmp.Or(a.format, time.RFC3339Nano).
+		format := a.format
+		if format == "" {
+			format = time.RFC3339Nano
+		}
+		n0 := len(b)
+		b = a.tt.AppendFormat(b, format)
+		// Not all Go timestamps can be represented as valid RFC 3339.
+		// Explicitly check for these edge cases.
+		// See https://go.dev/issue/4556 and https://go.dev/issue/54580.
+		switch b := b[n0:]; {
+		case b[len("9999")] != '-': // year must be exactly 4 digits wide
+			return b, errors.New("year outside of range [0,9999]")
+		case b[len(b)-1] != 'Z':
+			c := b[len(b)-len("Z07:00")]
+			if ('0' <= c && c <= '9') || parseDec2(b[len(b)-len("07:00"):]) >= 24 {
+				return b, errors.New("timezone hour outside of range [0,23]")
+			}
+		}
+		return b, nil
+	case math.MaxUint:
+		return a.tt.AppendFormat(b, a.format), nil
+	default:
+		return appendTimeUnix(b, a.tt, a.base), nil
+	}
+}
+
+func (a *timeArshaler) unmarshal(b []byte) (err error) {
+	switch a.base {
+	case 0:
+		// Use time.Time.UnmarshalText to avoid possible string allocation.
+		if err := a.tt.UnmarshalText(b); err != nil {
+			return err
+		}
+		// TODO(https://go.dev/issue/57912):
+		// RFC 3339 specifies the grammar for a valid timestamp.
+		// However, the parsing functionality in "time" is too loose and
+		// incorrectly accepts invalid timestamps as valid.
+		// Remove these manual checks when "time" checks it for us.
+		newParseError := func(layout, value, layoutElem, valueElem, message string) error {
+			return &time.ParseError{Layout: layout, Value: value, LayoutElem: layoutElem, ValueElem: valueElem, Message: message}
+		}
+		switch {
+		case b[len("2006-01-02T")+1] == ':': // hour must be two digits
+			return newParseError(time.RFC3339, string(b), "15", string(b[len("2006-01-02T"):][:1]), "")
+		case b[len("2006-01-02T15:04:05")] == ',': // sub-second separator must be a period
+			return newParseError(time.RFC3339, string(b), ".", ",", "")
+		case b[len(b)-1] != 'Z':
+			switch {
+			case parseDec2(b[len(b)-len("07:00"):]) >= 24: // timezone hour must be in range
+				return newParseError(time.RFC3339, string(b), "Z07:00", string(b[len(b)-len("Z07:00"):]), ": timezone hour out of range")
+			case parseDec2(b[len(b)-len("00"):]) >= 60: // timezone minute must be in range
+				return newParseError(time.RFC3339, string(b), "Z07:00", string(b[len(b)-len("Z07:00"):]), ": timezone minute out of range")
+			}
+		}
+		return nil
+	case math.MaxUint:
+		a.tt, err = time.Parse(a.format, string(b))
+		return err
+	default:
+		a.tt, err = parseTimeUnix(b, a.base)
+		return err
+	}
+}
+
+// appendDurationBase10 appends d formatted as a decimal fractional number,
+// where pow10 is a power-of-10 used to scale down the number.
+func appendDurationBase10(b []byte, d time.Duration, pow10 uint) []byte {
+	b, n := mayAppendDurationSign(b, d)            // append sign
+	whole, frac := bits.Div64(0, n, uint64(pow10)) // compute whole and frac fields
+	b = strconv.AppendUint(b, whole, 10)           // append whole field
+	return appendFracBase10(b, uint(frac), pow10)  // append frac field
+}
+
+// parseDurationBase10 parses d from a decimal fractional number,
+// where pow10 is a power-of-10 used to scale up the number.
+func parseDurationBase10(b []byte, pow10 uint) (time.Duration, error) {
+	suffix, neg := consumeSign(b)                            // consume sign
+	wholeBytes, fracBytes := bytesCutByte(suffix, '.', true) // consume whole and frac fields
+	whole, okWhole := jsonwire.ParseUint(wholeBytes)         // parse whole field; may overflow
+	frac, okFrac := parseFracBase10(fracBytes, pow10)        // parse frac field
+	hi, lo := bits.Mul64(whole, uint64(pow10))               // overflow if hi > 0
+	sum, co := bits.Add64(lo, uint64(frac), 0)               // overflow if co > 0
+	switch d := mayApplyDurationSign(sum, neg); {            // overflow if neg != (d < 0)
+	case (!okWhole && whole != math.MaxUint64) || !okFrac:
+		return 0, fmt.Errorf("invalid duration %q: %w", b, strconv.ErrSyntax)
+	case !okWhole || hi > 0 || co > 0 || neg != (d < 0):
+		return 0, fmt.Errorf("invalid duration %q: %w", b, strconv.ErrRange)
+	default:
+		return d, nil
+	}
+}
+
+// appendDurationBase60 appends d formatted with H:MM:SS.SSS notation.
+func appendDurationBase60(b []byte, d time.Duration) []byte {
+	b, n := mayAppendDurationSign(b, d)                    // append sign
+	n, nsec := bits.Div64(0, n, 1e9)                       // compute nsec field
+	n, sec := bits.Div64(0, n, 60)                         // compute sec field
+	hour, min := bits.Div64(0, n, 60)                      // compute hour and min fields
+	b = strconv.AppendUint(b, hour, 10)                    // append hour field
+	b = append(b, ':', '0'+byte(min/10), '0'+byte(min%10)) // append min field
+	b = append(b, ':', '0'+byte(sec/10), '0'+byte(sec%10)) // append sec field
+	return appendFracBase10(b, uint(nsec), 1e9)            // append nsec field
+}
+
+// parseDurationBase60 parses d formatted with H:MM:SS.SSS notation.
+// The exact grammar is `-?(0|[1-9][0-9]*):[0-5][0-9]:[0-5][0-9]([.][0-9]+)?`.
+func parseDurationBase60(b []byte) (time.Duration, error) {
+	checkBase60 := func(b []byte) bool {
+		return len(b) == 2 && ('0' <= b[0] && b[0] <= '5') && '0' <= b[1] && b[1] <= '9'
+	}
+	suffix, neg := consumeSign(b)                            // consume sign
+	hourBytes, suffix := bytesCutByte(suffix, ':', false)    // consume hour field
+	minBytes, suffix := bytesCutByte(suffix, ':', false)     // consume min field
+	secBytes, nsecBytes := bytesCutByte(suffix, '.', true)   // consume sec and nsec fields
+	hour, okHour := jsonwire.ParseUint(hourBytes)            // parse hour field; may overflow
+	min := parseDec2(minBytes)                               // parse min field
+	sec := parseDec2(secBytes)                               // parse sec field
+	nsec, okNsec := parseFracBase10(nsecBytes, 1e9)          // parse nsec field
+	n := uint64(min)*60*1e9 + uint64(sec)*1e9 + uint64(nsec) // cannot overflow
+	hi, lo := bits.Mul64(hour, 60*60*1e9)                    // overflow if hi > 0
+	sum, co := bits.Add64(lo, n, 0)                          // overflow if co > 0
+	switch d := mayApplyDurationSign(sum, neg); {            // overflow if neg != (d < 0)
+	case (!okHour && hour != math.MaxUint64) || !checkBase60(minBytes) || !checkBase60(secBytes) || !okNsec:
+		return 0, fmt.Errorf("invalid duration %q: %w", b, strconv.ErrSyntax)
+	case !okHour || hi > 0 || co > 0 || neg != (d < 0):
+		return 0, fmt.Errorf("invalid duration %q: %w", b, strconv.ErrRange)
+	default:
+		return d, nil
+	}
+}
+
+// mayAppendDurationSign appends a negative sign if n is negative.
+func mayAppendDurationSign(b []byte, d time.Duration) ([]byte, uint64) {
+	if d < 0 {
+		b = append(b, '-')
+		d *= -1
+	}
+	return b, uint64(d)
+}
+
+// mayApplyDurationSign inverts n if neg is specified.
+func mayApplyDurationSign(n uint64, neg bool) time.Duration {
+	if neg {
+		return -1 * time.Duration(n)
+	} else {
+		return +1 * time.Duration(n)
+	}
+}
+
+// appendTimeUnix appends t formatted as a decimal fractional number,
+// where pow10 is a power-of-10 used to scale up the number.
+func appendTimeUnix(b []byte, t time.Time, pow10 uint) []byte {
+	sec, nsec := t.Unix(), int64(t.Nanosecond())
+	if sec < 0 {
+		b = append(b, '-')
+		sec, nsec = negateSecNano(sec, nsec)
+	}
+	switch {
+	case pow10 == 1e0: // fast case where units is in seconds
+		b = strconv.AppendUint(b, uint64(sec), 10)
+		return appendFracBase10(b, uint(nsec), 1e9)
+	case uint64(sec) < 1e9: // intermediate case where units is not seconds, but no overflow
+		b = strconv.AppendUint(b, uint64(sec)*uint64(pow10)+uint64(uint(nsec)/(1e9/pow10)), 10)
+		return appendFracBase10(b, (uint(nsec)*pow10)%1e9, 1e9)
+	default: // slow case where units is not seconds and overflow would occur
+		b = strconv.AppendUint(b, uint64(sec), 10)
+		b = appendPaddedBase10(b, uint(uint(nsec)/(1e9/pow10)), pow10)
+		return appendFracBase10(b, (uint(nsec)*pow10)%1e9, 1e9)
+	}
+}
+
+// parseTimeUnix parses t formatted as a decimal fractional number,
+// where pow10 is a power-of-10 used to scale down the number.
+func parseTimeUnix(b []byte, pow10 uint) (time.Time, error) {
+	suffix, neg := consumeSign(b)                            // consume sign
+	wholeBytes, fracBytes := bytesCutByte(suffix, '.', true) // consume whole and frac fields
+	whole, okWhole := jsonwire.ParseUint(wholeBytes)         // parse whole field; may overflow
+	frac, okFrac := parseFracBase10(fracBytes, 1e9/pow10)    // parse frac field
+	var sec, nsec int64
+	switch {
+	case pow10 == 1e0: // fast case where units is in seconds
+		sec = int64(whole) // check overflow later after negation
+		nsec = int64(frac) // cannot overflow
+	case okWhole: // intermediate case where units is not seconds, but no overflow
+		sec = int64(whole / uint64(pow10))                         // check overflow later after negation
+		nsec = int64((uint(whole)%pow10)*(1e9/pow10) + uint(frac)) // cannot overflow
+	case !okWhole && whole == math.MaxUint64: // slow case where units is not seconds and overflow occurred
+		width := int(math.Log10(float64(pow10)))                                // compute len(strconv.Itoa(pow10-1))
+		whole, okWhole = jsonwire.ParseUint(wholeBytes[:len(wholeBytes)-width]) // parse the upper whole field
+		mid, _ := parsePaddedBase10(wholeBytes[len(wholeBytes)-width:], pow10)  // parse the lower whole field
+		sec = int64(whole)                                                      // check overflow later after negation
+		nsec = int64(uint(mid)*(1e9/pow10) + frac)                              // cannot overflow
+	}
+	if neg {
+		sec, nsec = negateSecNano(sec, nsec)
+	}
+	switch t := time.Unix(sec, nsec).UTC(); {
+	case (!okWhole && whole != math.MaxUint64) || !okFrac:
+		return time.Time{}, fmt.Errorf("invalid time %q: %w", b, strconv.ErrSyntax)
+	case !okWhole || neg != (t.Unix() < 0):
+		return time.Time{}, fmt.Errorf("invalid time %q: %w", b, strconv.ErrRange)
+	default:
+		return t, nil
+	}
+}
+
+// negateSecNano negates a Unix timestamp, where nsec must be within [0, 1e9).
+func negateSecNano(sec, nsec int64) (int64, int64) {
+	sec = ^sec               // twos-complement negation (i.e., -1*sec + 1)
+	nsec = -nsec + 1e9       // negate nsec and add 1e9 (which is the extra +1 from sec negation)
+	sec += int64(nsec / 1e9) // handle possible overflow of nsec if it started as zero
+	nsec %= 1e9              // ensure nsec stays within [0, 1e9)
+	return sec, nsec
+}
+
+// appendFracBase10 appends the fraction of n/max10,
+// where max10 is a power-of-10 that is larger than n.
+func appendFracBase10(b []byte, n, max10 uint) []byte {
+	if n == 0 {
+		return b
+	}
+	return bytes.TrimRight(appendPaddedBase10(append(b, '.'), n, max10), "0")
+}
+
+// parseFracBase10 parses the fraction of n/max10,
+// where max10 is a power-of-10 that is larger than n.
+func parseFracBase10(b []byte, max10 uint) (n uint, ok bool) {
+	switch {
+	case len(b) == 0:
+		return 0, true
+	case len(b) < len(".0") || b[0] != '.':
+		return 0, false
+	}
+	return parsePaddedBase10(b[len("."):], max10)
+}
+
+// appendPaddedBase10 appends a zero-padded encoding of n,
+// where max10 is a power-of-10 that is larger than n.
+func appendPaddedBase10(b []byte, n, max10 uint) []byte {
+	if n < max10/10 {
+		// Formatting of n is shorter than log10(max10),
+		// so add max10/10 to ensure the length is equal to log10(max10).
+		i := len(b)
+		b = strconv.AppendUint(b, uint64(n+max10/10), 10)
+		b[i]-- // subtract the addition of max10/10
+		return b
+	}
+	return strconv.AppendUint(b, uint64(n), 10)
+}
+
+// parsePaddedBase10 parses b as the zero-padded encoding of n,
+// where max10 is a power-of-10 that is larger than n.
+// Truncated suffix is treated as implicit zeros.
+// Extended suffix is ignored, but verified to contain only digits.
+func parsePaddedBase10(b []byte, max10 uint) (n uint, ok bool) {
+	pow10 := uint(1)
+	for pow10 < max10 {
+		n *= 10
+		if len(b) > 0 {
+			if b[0] < '0' || '9' < b[0] {
+				return n, false
+			}
+			n += uint(b[0] - '0')
+			b = b[1:]
+		}
+		pow10 *= 10
+	}
+	if len(b) > 0 && len(bytes.TrimRight(b, "0123456789")) > 0 {
+		return n, false // trailing characters are not digits
+	}
+	return n, true
+}
+
+// consumeSign consumes an optional leading negative sign.
+func consumeSign(b []byte) ([]byte, bool) {
+	if len(b) > 0 && b[0] == '-' {
+		return b[len("-"):], true
+	}
+	return b, false
+}
+
+// bytesCutByte is similar to bytes.Cut(b, []byte{c}),
+// except c may optionally be included as part of the suffix.
+func bytesCutByte(b []byte, c byte, include bool) ([]byte, []byte) {
+	if i := bytes.IndexByte(b, c); i >= 0 {
+		if include {
+			return b[:i], b[i:]
+		}
+		return b[:i], b[i+1:]
+	}
+	return b, nil
+}
+
+// parseDec2 parses b as an unsigned, base-10, 2-digit number.
+// The result is undefined if digits are not base-10.
+func parseDec2(b []byte) byte {
+	if len(b) < 2 {
+		return 0
+	}
+	return 10*(b[0]-'0') + (b[1] - '0')
+}

vendor/github.com/go-json-experiment/json/doc.go

@@ -0,0 +1,170 @@
+// 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 json implements semantic processing of JSON as specified in RFC 8259.
+// JSON is a simple data interchange format that can represent
+// primitive data types such as booleans, strings, and numbers,
+// in addition to structured data types such as objects and arrays.
+//
+// [Marshal] and [Unmarshal] encode and decode Go values
+// to/from JSON text contained within a []byte.
+// [MarshalWrite] and [UnmarshalRead] operate on JSON text
+// by writing to or reading from an [io.Writer] or [io.Reader].
+// [MarshalEncode] and [UnmarshalDecode] operate on JSON text
+// by encoding to or decoding from a [jsontext.Encoder] or [jsontext.Decoder].
+// [Options] may be passed to each of the marshal or unmarshal functions
+// to configure the semantic behavior of marshaling and unmarshaling
+// (i.e., alter how JSON data is understood as Go data and vice versa).
+// [jsontext.Options] may also be passed to the marshal or unmarshal functions
+// to configure the syntactic behavior of encoding or decoding.
+//
+// The data types of JSON are mapped to/from the data types of Go based on
+// the closest logical equivalent between the two type systems. For example,
+// a JSON boolean corresponds with a Go bool,
+// a JSON string corresponds with a Go string,
+// a JSON number corresponds with a Go int, uint or float,
+// a JSON array corresponds with a Go slice or array, and
+// a JSON object corresponds with a Go struct or map.
+// See the documentation on [Marshal] and [Unmarshal] for a comprehensive list
+// of how the JSON and Go type systems correspond.
+//
+// Arbitrary Go types can customize their JSON representation by implementing
+// [MarshalerV1], [MarshalerV2], [UnmarshalerV1], or [UnmarshalerV2].
+// This provides authors of Go types with control over how their types are
+// serialized as JSON. Alternatively, users can implement functions that match
+// [MarshalFuncV1], [MarshalFuncV2], [UnmarshalFuncV1], or [UnmarshalFuncV2]
+// to specify the JSON representation for arbitrary types.
+// This provides callers of JSON functionality with control over
+// how any arbitrary type is serialized as JSON.
+//
+// # JSON Representation of Go structs
+//
+// A Go struct is naturally represented as a JSON object,
+// where each Go struct field corresponds with a JSON object member.
+// When marshaling, all Go struct fields are recursively encoded in depth-first
+// order as JSON object members except those that are ignored or omitted.
+// When unmarshaling, JSON object members are recursively decoded
+// into the corresponding Go struct fields.
+// Object members that do not match any struct fields,
+// also known as “unknown members”, are ignored by default or rejected
+// if [RejectUnknownMembers] is specified.
+//
+// The representation of each struct field can be customized in the
+// "json" struct field tag, where the tag is a comma separated list of options.
+// As a special case, if the entire tag is `json:"-"`,
+// then the field is ignored with regard to its JSON representation.
+//
+// The first option is the JSON object name override for the Go struct field.
+// If the name is not specified, then the Go struct field name
+// is used as the JSON object name. JSON names containing commas or quotes,
+// or names identical to "" or "-", can be specified using
+// a single-quoted string literal, where the syntax is identical to
+// the Go grammar for a double-quoted string literal,
+// but instead uses single quotes as the delimiters.
+// By default, unmarshaling uses case-sensitive matching to identify
+// the Go struct field associated with a JSON object name.
+//
+// After the name, the following tag options are supported:
+//
+//   - omitzero: When marshaling, the "omitzero" option specifies that
+//     the struct field should be omitted if the field value is zero
+//     as determined by the "IsZero() bool" method if present,
+//     otherwise based on whether the field is the zero Go value.
+//     This option has no effect when unmarshaling.
+//
+//   - omitempty: When marshaling, the "omitempty" option specifies that
+//     the struct field should be omitted if the field value would have been
+//     encoded as a JSON null, empty string, empty object, or empty array.
+//     This option has no effect when unmarshaling.
+//
+//   - string: The "string" option specifies that [StringifyNumbers]
+//     be set when marshaling or unmarshaling a struct field value.
+//     This causes numeric types to be encoded as a JSON number
+//     within a JSON string, and to be decoded from either a JSON number or
+//     a JSON string containing a JSON number.
+//     This extra level of encoding is often necessary since
+//     many JSON parsers cannot precisely represent 64-bit integers.
+//
+//   - nocase: When unmarshaling, the "nocase" option specifies that
+//     if the JSON object name does not exactly match the JSON name
+//     for any of the struct fields, then it attempts to match the struct field
+//     using a case-insensitive match that also ignores dashes and underscores.
+//     If multiple fields match,
+//     the first declared field in breadth-first order takes precedence.
+//     This takes precedence even if [MatchCaseInsensitiveNames] is set to false.
+//     This cannot be specified together with the "strictcase" option.
+//
+//   - strictcase: When unmarshaling, the "strictcase" option specifies that the
+//     JSON object name must exactly match the JSON name for the struct field.
+//     This takes precedence even if [MatchCaseInsensitiveNames] is set to true.
+//     This cannot be specified together with the "nocase" option.
+//
+//   - inline: The "inline" option specifies that
+//     the JSON representable content of this field type is to be promoted
+//     as if they were specified in the parent struct.
+//     It is the JSON equivalent of Go struct embedding.
+//     A Go embedded field is implicitly inlined unless an explicit JSON name
+//     is specified. The inlined field must be a Go struct
+//     (that does not implement any JSON methods), [jsontext.Value],
+//     map[string]T, or an unnamed pointer to such types. When marshaling,
+//     inlined fields from a pointer type are omitted if it is nil.
+//     Inlined fields of type [jsontext.Value] and map[string]T are called
+//     “inlined fallbacks” as they can represent all possible
+//     JSON object members not directly handled by the parent struct.
+//     Only one inlined fallback field may be specified in a struct,
+//     while many non-fallback fields may be specified. This option
+//     must not be specified with any other option (including the JSON name).
+//
+//   - unknown: The "unknown" option is a specialized variant
+//     of the inlined fallback to indicate that this Go struct field
+//     contains any number of unknown JSON object members. The field type must
+//     be a [jsontext.Value], map[string]T, or an unnamed pointer to such types.
+//     If [DiscardUnknownMembers] is specified when marshaling,
+//     the contents of this field are ignored.
+//     If [RejectUnknownMembers] is specified when unmarshaling,
+//     any unknown object members are rejected regardless of whether
+//     an inlined fallback with the "unknown" option exists. This option
+//     must not be specified with any other option (including the JSON name).
+//
+//   - format: The "format" option specifies a format flag
+//     used to specialize the formatting of the field value.
+//     The option is a key-value pair specified as "format:value" where
+//     the value must be either a literal consisting of letters and numbers
+//     (e.g., "format:RFC3339") or a single-quoted string literal
+//     (e.g., "format:'2006-01-02'"). The interpretation of the format flag
+//     is determined by the struct field type.
+//
+// The "omitzero" and "omitempty" options are mostly semantically identical.
+// The former is defined in terms of the Go type system,
+// while the latter in terms of the JSON type system.
+// Consequently they behave differently in some circumstances.
+// For example, only a nil slice or map is omitted under "omitzero", while
+// an empty slice or map is omitted under "omitempty" regardless of nilness.
+// The "omitzero" option is useful for types with a well-defined zero value
+// (e.g., [net/netip.Addr]) or have an IsZero method (e.g., [time.Time.IsZero]).
+//
+// Every Go struct corresponds to a list of JSON representable fields
+// which is constructed by performing a breadth-first search over
+// all struct fields (excluding unexported or ignored fields),
+// where the search recursively descends into inlined structs.
+// The set of non-inlined fields in a struct must have unique JSON names.
+// If multiple fields all have the same JSON name, then the one
+// at shallowest depth takes precedence and the other fields at deeper depths
+// are excluded from the list of JSON representable fields.
+// If multiple fields at the shallowest depth have the same JSON name,
+// but exactly one is explicitly tagged with a JSON name,
+// then that field takes precedence and all others are excluded from the list.
+// This is analogous to Go visibility rules for struct field selection
+// with embedded struct types.
+//
+// Marshaling or unmarshaling a non-empty struct
+// without any JSON representable fields results in a [SemanticError].
+// Unexported fields must not have any `json` tags except for `json:"-"`.
+package json
+
+// requireKeyedLiterals can be embedded in a struct to require keyed literals.
+type requireKeyedLiterals struct{}
+
+// nonComparable can be embedded in a struct to prevent comparability.
+type nonComparable [0]func()

vendor/github.com/go-json-experiment/json/errors.go

@@ -0,0 +1,126 @@
+// 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 json
+
+import (
+	"reflect"
+	"strconv"
+	"strings"
+
+	"github.com/go-json-experiment/json/jsontext"
+)
+
+const errorPrefix = "json: "
+
+// SemanticError describes an error determining the meaning
+// of JSON data as Go data or vice-versa.
+//
+// The contents of this error as produced by this package may change over time.
+type SemanticError struct {
+	requireKeyedLiterals
+	nonComparable
+
+	action string // either "marshal" or "unmarshal"
+
+	// ByteOffset indicates that an error occurred after this byte offset.
+	ByteOffset int64
+	// JSONPointer indicates that an error occurred within this JSON value
+	// as indicated using the JSON Pointer notation (see RFC 6901).
+	JSONPointer string
+
+	// JSONKind is the JSON kind that could not be handled.
+	JSONKind jsontext.Kind // may be zero if unknown
+	// GoType is the Go type that could not be handled.
+	GoType reflect.Type // may be nil if unknown
+
+	// Err is the underlying error.
+	Err error // may be nil
+}
+
+func (e *SemanticError) Error() string {
+	var sb strings.Builder
+	sb.WriteString(errorPrefix)
+
+	// Hyrum-proof the error message by deliberately switching between
+	// two equivalent renderings of the same error message.
+	// The randomization is tied to the Hyrum-proofing already applied
+	// on map iteration in Go.
+	for phrase := range map[string]struct{}{"cannot": {}, "unable to": {}} {
+		sb.WriteString(phrase)
+		break // use whichever phrase we get in the first iteration
+	}
+
+	// Format action.
+	var preposition string
+	switch e.action {
+	case "marshal":
+		sb.WriteString(" marshal")
+		preposition = " from"
+	case "unmarshal":
+		sb.WriteString(" unmarshal")
+		preposition = " into"
+	default:
+		sb.WriteString(" handle")
+		preposition = " with"
+	}
+
+	// Format JSON kind.
+	var omitPreposition bool
+	switch e.JSONKind {
+	case 'n':
+		sb.WriteString(" JSON null")
+	case 'f', 't':
+		sb.WriteString(" JSON boolean")
+	case '"':
+		sb.WriteString(" JSON string")
+	case '0':
+		sb.WriteString(" JSON number")
+	case '{', '}':
+		sb.WriteString(" JSON object")
+	case '[', ']':
+		sb.WriteString(" JSON array")
+	default:
+		omitPreposition = true
+	}
+
+	// Format Go type.
+	if e.GoType != nil {
+		if !omitPreposition {
+			sb.WriteString(preposition)
+		}
+		sb.WriteString(" Go value of type ")
+		sb.WriteString(e.GoType.String())
+	}
+
+	// Format where.
+	switch {
+	case e.JSONPointer != "":
+		sb.WriteString(" within JSON value at ")
+		sb.WriteString(strconv.Quote(e.JSONPointer))
+	case e.ByteOffset > 0:
+		sb.WriteString(" after byte offset ")
+		sb.WriteString(strconv.FormatInt(e.ByteOffset, 10))
+	}
+
+	// Format underlying error.
+	if e.Err != nil {
+		sb.WriteString(": ")
+		sb.WriteString(e.Err.Error())
+	}
+
+	return sb.String()
+}
+func (e *SemanticError) Unwrap() error {
+	return e.Err
+}
+
+func firstError(errs ...error) error {
+	for _, err := range errs {
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/github.com/go-json-experiment/json/fields.go

@@ -0,0 +1,547 @@
+// Copyright 2021 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 json
+
+import (
+	"cmp"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"slices"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+var errIgnoredField = errors.New("ignored field")
+
+type isZeroer interface {
+	IsZero() bool
+}
+
+var isZeroerType = reflect.TypeOf((*isZeroer)(nil)).Elem()
+
+type structFields struct {
+	flattened       []structField // listed in depth-first ordering
+	byActualName    map[string]*structField
+	byFoldedName    map[string][]*structField
+	inlinedFallback *structField
+}
+
+// lookupByFoldedName looks up name by a case-insensitive match
+// that also ignores the presence of dashes and underscores.
+func (fs *structFields) lookupByFoldedName(name []byte) []*structField {
+	return fs.byFoldedName[string(foldName(name))]
+}
+
+type structField struct {
+	id      int   // unique numeric ID in breadth-first ordering
+	index   []int // index into a struct according to reflect.Type.FieldByIndex
+	typ     reflect.Type
+	fncs    *arshaler
+	isZero  func(addressableValue) bool
+	isEmpty func(addressableValue) bool
+	fieldOptions
+}
+
+func makeStructFields(root reflect.Type) (structFields, *SemanticError) {
+	// Setup a queue for a breath-first search.
+	var queueIndex int
+	type queueEntry struct {
+		typ           reflect.Type
+		index         []int
+		visitChildren bool // whether to recursively visit inlined field in this struct
+	}
+	queue := []queueEntry{{root, nil, true}}
+	seen := map[reflect.Type]bool{root: true}
+
+	// Perform a breadth-first search over all reachable fields.
+	// This ensures that len(f.index) will be monotonically increasing.
+	var allFields, inlinedFallbacks []structField
+	for queueIndex < len(queue) {
+		qe := queue[queueIndex]
+		queueIndex++
+
+		t := qe.typ
+		inlinedFallbackIndex := -1         // index of last inlined fallback field in current struct
+		namesIndex := make(map[string]int) // index of each field with a given JSON object name in current struct
+		var hasAnyJSONTag bool             // whether any Go struct field has a `json` tag
+		var hasAnyJSONField bool           // whether any JSON serializable fields exist in current struct
+		for i := 0; i < t.NumField(); i++ {
+			sf := t.Field(i)
+			_, hasTag := sf.Tag.Lookup("json")
+			hasAnyJSONTag = hasAnyJSONTag || hasTag
+			options, ignored, err := parseFieldOptions(sf)
+			if err != nil {
+				return structFields{}, &SemanticError{GoType: t, Err: err}
+			} else if ignored {
+				continue
+			}
+			hasAnyJSONField = true
+			f := structField{
+				// Allocate a new slice (len=N+1) to hold both
+				// the parent index (len=N) and the current index (len=1).
+				// Do this to avoid clobbering the memory of the parent index.
+				index:        append(append(make([]int, 0, len(qe.index)+1), qe.index...), i),
+				typ:          sf.Type,
+				fieldOptions: options,
+			}
+			if sf.Anonymous && !f.hasName {
+				f.inline = true // implied by use of Go embedding without an explicit name
+			}
+			if f.inline || f.unknown {
+				// Handle an inlined field that serializes to/from
+				// zero or more JSON object members.
+
+				if f.inline && f.unknown {
+					err := fmt.Errorf("Go struct field %s cannot have both `inline` and `unknown` specified", sf.Name)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+				switch f.fieldOptions {
+				case fieldOptions{name: f.name, quotedName: f.quotedName, inline: true}:
+				case fieldOptions{name: f.name, quotedName: f.quotedName, unknown: true}:
+				default:
+					err := fmt.Errorf("Go struct field %s cannot have any options other than `inline` or `unknown` specified", sf.Name)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+
+				// Unwrap one level of pointer indirection similar to how Go
+				// only allows embedding either T or *T, but not **T.
+				tf := f.typ
+				if tf.Kind() == reflect.Pointer && tf.Name() == "" {
+					tf = tf.Elem()
+				}
+				// Reject any types with custom serialization otherwise
+				// it becomes impossible to know what sub-fields to inline.
+				if which := implementsWhich(tf,
+					jsonMarshalerV2Type, jsonMarshalerV1Type, textMarshalerType,
+					jsonUnmarshalerV2Type, jsonUnmarshalerV1Type, textUnmarshalerType,
+				); which != nil && tf != jsontextValueType {
+					err := fmt.Errorf("inlined Go struct field %s of type %s must not implement JSON marshal or unmarshal methods", sf.Name, tf)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+
+				// Handle an inlined field that serializes to/from
+				// a finite number of JSON object members backed by a Go struct.
+				if tf.Kind() == reflect.Struct {
+					if f.unknown {
+						err := fmt.Errorf("inlined Go struct field %s of type %s with `unknown` tag must be a Go map of string key or a jsontext.Value", sf.Name, tf)
+						return structFields{}, &SemanticError{GoType: t, Err: err}
+					}
+					if qe.visitChildren {
+						queue = append(queue, queueEntry{tf, f.index, !seen[tf]})
+					}
+					seen[tf] = true
+					continue
+				}
+
+				// Handle an inlined field that serializes to/from any number of
+				// JSON object members back by a Go map or jsontext.Value.
+				switch {
+				case tf == jsontextValueType:
+					f.fncs = nil // specially handled in arshal_inlined.go
+				case tf.Kind() == reflect.Map && tf.Key() == stringType:
+					f.fncs = lookupArshaler(tf.Elem())
+				default:
+					err := fmt.Errorf("inlined Go struct field %s of type %s must be a Go struct, Go map of string key, or jsontext.Value", sf.Name, tf)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+
+				// Reject multiple inlined fallback fields within the same struct.
+				if inlinedFallbackIndex >= 0 {
+					err := fmt.Errorf("inlined Go struct fields %s and %s cannot both be a Go map or jsontext.Value", t.Field(inlinedFallbackIndex).Name, sf.Name)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+				inlinedFallbackIndex = i
+
+				inlinedFallbacks = append(inlinedFallbacks, f)
+			} else {
+				// Handle normal Go struct field that serializes to/from
+				// a single JSON object member.
+
+				// Provide a function that uses a type's IsZero method.
+				switch {
+				case sf.Type.Kind() == reflect.Interface && sf.Type.Implements(isZeroerType):
+					f.isZero = func(va addressableValue) bool {
+						// Avoid panics calling IsZero on a nil interface or
+						// non-nil interface with nil pointer.
+						return va.IsNil() || (va.Elem().Kind() == reflect.Pointer && va.Elem().IsNil()) || va.Interface().(isZeroer).IsZero()
+					}
+				case sf.Type.Kind() == reflect.Pointer && sf.Type.Implements(isZeroerType):
+					f.isZero = func(va addressableValue) bool {
+						// Avoid panics calling IsZero on nil pointer.
+						return va.IsNil() || va.Interface().(isZeroer).IsZero()
+					}
+				case sf.Type.Implements(isZeroerType):
+					f.isZero = func(va addressableValue) bool { return va.Interface().(isZeroer).IsZero() }
+				case reflect.PointerTo(sf.Type).Implements(isZeroerType):
+					f.isZero = func(va addressableValue) bool { return va.Addr().Interface().(isZeroer).IsZero() }
+				}
+
+				// Provide a function that can determine whether the value would
+				// serialize as an empty JSON value.
+				switch sf.Type.Kind() {
+				case reflect.String, reflect.Map, reflect.Array, reflect.Slice:
+					f.isEmpty = func(va addressableValue) bool { return va.Len() == 0 }
+				case reflect.Pointer, reflect.Interface:
+					f.isEmpty = func(va addressableValue) bool { return va.IsNil() }
+				}
+
+				// Reject user-specified names with invalid UTF-8.
+				if !utf8.ValidString(f.name) {
+					err := fmt.Errorf("Go struct field %s has JSON object name %q with invalid UTF-8", sf.Name, f.name)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+				// Reject multiple fields with same name within the same struct.
+				if j, ok := namesIndex[f.name]; ok {
+					err := fmt.Errorf("Go struct fields %s and %s conflict over JSON object name %q", t.Field(j).Name, sf.Name, f.name)
+					return structFields{}, &SemanticError{GoType: t, Err: err}
+				}
+				namesIndex[f.name] = i
+
+				f.id = len(allFields)
+				f.fncs = lookupArshaler(sf.Type)
+				allFields = append(allFields, f)
+			}
+		}
+
+		// NOTE: New users to the json package are occasionally surprised that
+		// unexported fields are ignored. This occurs by necessity due to our
+		// inability to directly introspect such fields with Go reflection
+		// without the use of unsafe.
+		//
+		// To reduce friction here, refuse to serialize any Go struct that
+		// has no JSON serializable fields, has at least one Go struct field,
+		// and does not have any `json` tags present. For example,
+		// errors returned by errors.New would fail to serialize.
+		isEmptyStruct := t.NumField() == 0
+		if !isEmptyStruct && !hasAnyJSONTag && !hasAnyJSONField {
+			err := errors.New("Go struct has no exported fields")
+			return structFields{}, &SemanticError{GoType: t, Err: err}
+		}
+	}
+
+	// Sort the fields by exact name (breaking ties by depth and
+	// then by presence of an explicitly provided JSON name).
+	// Select the dominant field from each set of fields with the same name.
+	// If multiple fields have the same name, then the dominant field
+	// is the one that exists alone at the shallowest depth,
+	// or the one that is uniquely tagged with a JSON name.
+	// Otherwise, no dominant field exists for the set.
+	flattened := allFields[:0]
+	slices.SortFunc(allFields, func(x, y structField) int {
+		switch {
+		case x.name != y.name:
+			return strings.Compare(x.name, y.name)
+		case len(x.index) != len(y.index):
+			return cmp.Compare(len(x.index), len(y.index))
+		case x.hasName && !y.hasName:
+			return -1
+		case !x.hasName && y.hasName:
+			return +1
+		default:
+			return 0 // TODO(https://go.dev/issue/61643): Compare bools better.
+		}
+	})
+	for len(allFields) > 0 {
+		n := 1 // number of fields with the same exact name
+		for n < len(allFields) && allFields[n-1].name == allFields[n].name {
+			n++
+		}
+		if n == 1 || len(allFields[0].index) != len(allFields[1].index) || allFields[0].hasName != allFields[1].hasName {
+			flattened = append(flattened, allFields[0]) // only keep field if there is a dominant field
+		}
+		allFields = allFields[n:]
+	}
+
+	// Sort the fields according to a breadth-first ordering
+	// so that we can re-number IDs with the smallest possible values.
+	// This optimizes use of uintSet such that it fits in the 64-entry bit set.
+	slices.SortFunc(flattened, func(x, y structField) int {
+		return cmp.Compare(x.id, y.id)
+	})
+	for i := range flattened {
+		flattened[i].id = i
+	}
+
+	// Sort the fields according to a depth-first ordering
+	// as the typical order that fields are marshaled.
+	slices.SortFunc(flattened, func(x, y structField) int {
+		return slices.Compare(x.index, y.index)
+	})
+
+	// Compute the mapping of fields in the byActualName map.
+	// Pre-fold all names so that we can lookup folded names quickly.
+	fs := structFields{
+		flattened:    flattened,
+		byActualName: make(map[string]*structField, len(flattened)),
+		byFoldedName: make(map[string][]*structField, len(flattened)),
+	}
+	for i, f := range fs.flattened {
+		foldedName := string(foldName([]byte(f.name)))
+		fs.byActualName[f.name] = &fs.flattened[i]
+		fs.byFoldedName[foldedName] = append(fs.byFoldedName[foldedName], &fs.flattened[i])
+	}
+	for foldedName, fields := range fs.byFoldedName {
+		if len(fields) > 1 {
+			// The precedence order for conflicting nocase names
+			// is by breadth-first order, rather than depth-first order.
+			slices.SortFunc(fields, func(x, y *structField) int {
+				return cmp.Compare(x.id, y.id)
+			})
+			fs.byFoldedName[foldedName] = fields
+		}
+	}
+	if n := len(inlinedFallbacks); n == 1 || (n > 1 && len(inlinedFallbacks[0].index) != len(inlinedFallbacks[1].index)) {
+		fs.inlinedFallback = &inlinedFallbacks[0] // dominant inlined fallback field
+	}
+
+	return fs, nil
+}
+
+// matchFoldedName matches a case-insensitive name depending on the options.
+// It assumes that foldName(f.name) == foldName(name).
+//
+// Case-insensitive matching is used if the `nocase` tag option is specified
+// or the MatchCaseInsensitiveNames call option is specified
+// (and the `strictcase` tag option is not specified).
+// Functionally, the `nocase` and `strictcase` tag options take precedence.
+//
+// The v1 definition of case-insensitivity operated under strings.EqualFold
+// and would strictly compare dashes and underscores,
+// while the v2 definition would ignore the presence of dashes and underscores.
+// Thus, if the MatchCaseSensitiveDelimiter call option is specified,
+// the match is further restricted to using strings.EqualFold.
+func (f *structField) matchFoldedName(name []byte, flags *jsonflags.Flags) bool {
+	if f.casing == nocase || (flags.Get(jsonflags.MatchCaseInsensitiveNames) && f.casing != strictcase) {
+		if !flags.Get(jsonflags.MatchCaseSensitiveDelimiter) || strings.EqualFold(string(name), f.name) {
+			return true
+		}
+	}
+	return false
+}
+
+const (
+	nocase     = 1
+	strictcase = 2
+)
+
+type fieldOptions struct {
+	name       string
+	quotedName string // quoted name per RFC 8785, section 3.2.2.2.
+	hasName    bool
+	casing     int8 // either 0, nocase, or strictcase
+	inline     bool
+	unknown    bool
+	omitzero   bool
+	omitempty  bool
+	string     bool
+	format     string
+}
+
+// parseFieldOptions parses the `json` tag in a Go struct field as
+// a structured set of options configuring parameters such as
+// the JSON member name and other features.
+func parseFieldOptions(sf reflect.StructField) (out fieldOptions, ignored bool, err error) {
+	tag, hasTag := sf.Tag.Lookup("json")
+
+	// Check whether this field is explicitly ignored.
+	if tag == "-" {
+		return fieldOptions{}, true, nil
+	}
+
+	// Check whether this field is unexported.
+	if !sf.IsExported() {
+		// In contrast to v1, v2 no longer forwards exported fields from
+		// embedded fields of unexported types since Go reflection does not
+		// allow the same set of operations that are available in normal cases
+		// of purely exported fields.
+		// See https://go.dev/issue/21357 and https://go.dev/issue/24153.
+		if sf.Anonymous {
+			err = firstError(err, fmt.Errorf("embedded Go struct field %s of an unexported type must be explicitly ignored with a `json:\"-\"` tag", sf.Type.Name()))
+		}
+		// Tag options specified on an unexported field suggests user error.
+		if hasTag {
+			err = firstError(err, fmt.Errorf("unexported Go struct field %s cannot have non-ignored `json:%q` tag", sf.Name, tag))
+		}
+		return fieldOptions{}, true, err
+	}
+
+	// Determine the JSON member name for this Go field. A user-specified name
+	// may be provided as either an identifier or a single-quoted string.
+	// The single-quoted string allows arbitrary characters in the name.
+	// See https://go.dev/issue/2718 and https://go.dev/issue/3546.
+	out.name = sf.Name // always starts with an uppercase character
+	if len(tag) > 0 && !strings.HasPrefix(tag, ",") {
+		// For better compatibility with v1, accept almost any unescaped name.
+		n := len(tag) - len(strings.TrimLeftFunc(tag, func(r rune) bool {
+			return !strings.ContainsRune(",\\'\"`", r) // reserve comma, backslash, and quotes
+		}))
+		opt := tag[:n]
+		if n == 0 {
+			// Allow a single quoted string for arbitrary names.
+			var err2 error
+			opt, n, err2 = consumeTagOption(tag)
+			if err2 != nil {
+				err = firstError(err, fmt.Errorf("Go struct field %s has malformed `json` tag: %v", sf.Name, err2))
+			}
+		}
+		out.hasName = true
+		out.name = opt
+		tag = tag[n:]
+	}
+	b, _ := jsonwire.AppendQuote(nil, out.name, &jsonflags.Flags{})
+	out.quotedName = string(b)
+
+	// Handle any additional tag options (if any).
+	var wasFormat bool
+	seenOpts := make(map[string]bool)
+	for len(tag) > 0 {
+		// Consume comma delimiter.
+		if tag[0] != ',' {
+			err = firstError(err, fmt.Errorf("Go struct field %s has malformed `json` tag: invalid character %q before next option (expecting ',')", sf.Name, tag[0]))
+		} else {
+			tag = tag[len(","):]
+			if len(tag) == 0 {
+				err = firstError(err, fmt.Errorf("Go struct field %s has malformed `json` tag: invalid trailing ',' character", sf.Name))
+				break
+			}
+		}
+
+		// Consume and process the tag option.
+		opt, n, err2 := consumeTagOption(tag)
+		if err2 != nil {
+			err = firstError(err, fmt.Errorf("Go struct field %s has malformed `json` tag: %v", sf.Name, err2))
+		}
+		rawOpt := tag[:n]
+		tag = tag[n:]
+		switch {
+		case wasFormat:
+			err = firstError(err, fmt.Errorf("Go struct field %s has `format` tag option that was not specified last", sf.Name))
+		case strings.HasPrefix(rawOpt, "'") && strings.TrimFunc(opt, isLetterOrDigit) == "":
+			err = firstError(err, fmt.Errorf("Go struct field %s has unnecessarily quoted appearance of `%s` tag option; specify `%s` instead", sf.Name, rawOpt, opt))
+		}
+		switch opt {
+		case "nocase":
+			out.casing |= nocase
+		case "strictcase":
+			out.casing |= strictcase
+		case "inline":
+			out.inline = true
+		case "unknown":
+			out.unknown = true
+		case "omitzero":
+			out.omitzero = true
+		case "omitempty":
+			out.omitempty = true
+		case "string":
+			out.string = true
+		case "format":
+			if !strings.HasPrefix(tag, ":") {
+				err = firstError(err, fmt.Errorf("Go struct field %s is missing value for `format` tag option", sf.Name))
+				break
+			}
+			tag = tag[len(":"):]
+			opt, n, err2 := consumeTagOption(tag)
+			if err2 != nil {
+				err = firstError(err, fmt.Errorf("Go struct field %s has malformed value for `format` tag option: %v", sf.Name, err2))
+				break
+			}
+			tag = tag[n:]
+			out.format = opt
+			wasFormat = true
+		default:
+			// Reject keys that resemble one of the supported options.
+			// This catches invalid mutants such as "omitEmpty" or "omit_empty".
+			normOpt := strings.ReplaceAll(strings.ToLower(opt), "_", "")
+			switch normOpt {
+			case "nocase", "strictcase", "inline", "unknown", "omitzero", "omitempty", "string", "format":
+				err = firstError(err, fmt.Errorf("Go struct field %s has invalid appearance of `%s` tag option; specify `%s` instead", sf.Name, opt, normOpt))
+			}
+
+			// NOTE: Everything else is ignored. This does not mean it is
+			// forward compatible to insert arbitrary tag options since
+			// a future version of this package may understand that tag.
+		}
+
+		// Reject duplicates.
+		switch {
+		case out.casing == nocase|strictcase:
+			err = firstError(err, fmt.Errorf("Go struct field %s cannot have both `nocase` and `structcase` tag options", sf.Name))
+		case seenOpts[opt]:
+			err = firstError(err, fmt.Errorf("Go struct field %s has duplicate appearance of `%s` tag option", sf.Name, rawOpt))
+		}
+		seenOpts[opt] = true
+	}
+	return out, false, err
+}
+
+func consumeTagOption(in string) (string, int, error) {
+	// For legacy compatibility with v1, assume options are comma-separated.
+	i := strings.IndexByte(in, ',')
+	if i < 0 {
+		i = len(in)
+	}
+
+	switch r, _ := utf8.DecodeRuneInString(in); {
+	// Option as a Go identifier.
+	case r == '_' || unicode.IsLetter(r):
+		n := len(in) - len(strings.TrimLeftFunc(in, isLetterOrDigit))
+		return in[:n], n, nil
+	// Option as a single-quoted string.
+	case r == '\'':
+		// The grammar is nearly identical to a double-quoted Go string literal,
+		// but uses single quotes as the terminators. The reason for a custom
+		// grammar is because both backtick and double quotes cannot be used
+		// verbatim in a struct tag.
+		//
+		// Convert a single-quoted string to a double-quote string and rely on
+		// strconv.Unquote to handle the rest.
+		var inEscape bool
+		b := []byte{'"'}
+		n := len(`'`)
+		for len(in) > n {
+			r, rn := utf8.DecodeRuneInString(in[n:])
+			switch {
+			case inEscape:
+				if r == '\'' {
+					b = b[:len(b)-1] // remove escape character: `\'` => `'`
+				}
+				inEscape = false
+			case r == '\\':
+				inEscape = true
+			case r == '"':
+				b = append(b, '\\') // insert escape character: `"` => `\"`
+			case r == '\'':
+				b = append(b, '"')
+				n += len(`'`)
+				out, err := strconv.Unquote(string(b))
+				if err != nil {
+					return in[:i], i, fmt.Errorf("invalid single-quoted string: %s", in[:n])
+				}
+				return out, n, nil
+			}
+			b = append(b, in[n:][:rn]...)
+			n += rn
+		}
+		if n > 10 {
+			n = 10 // limit the amount of context printed in the error
+		}
+		return in[:i], i, fmt.Errorf("single-quoted string not terminated: %s...", in[:n])
+	case len(in) == 0:
+		return in[:i], i, io.ErrUnexpectedEOF
+	default:
+		return in[:i], i, fmt.Errorf("invalid character %q at start of option (expecting Unicode letter or single quote)", r)
+	}
+}
+
+func isLetterOrDigit(r rune) bool {
+	return r == '_' || unicode.IsLetter(r) || unicode.IsNumber(r)
+}

vendor/github.com/go-json-experiment/json/fold.go

@@ -0,0 +1,56 @@
+// 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 json
+
+import (
+	"unicode"
+	"unicode/utf8"
+)
+
+// foldName returns a folded string such that foldName(x) == foldName(y)
+// is similar to strings.EqualFold(x, y), but ignores underscore and dashes.
+// This allows foldName to match common naming conventions.
+func foldName(in []byte) []byte {
+	// This is inlinable to take advantage of "function outlining".
+	// See https://blog.filippo.io/efficient-go-apis-with-the-inliner/
+	var arr [32]byte // large enough for most JSON names
+	return appendFoldedName(arr[:0], in)
+}
+func appendFoldedName(out, in []byte) []byte {
+	for i := 0; i < len(in); {
+		// Handle single-byte ASCII.
+		if c := in[i]; c < utf8.RuneSelf {
+			if c != '_' && c != '-' {
+				if 'a' <= c && c <= 'z' {
+					c -= 'a' - 'A'
+				}
+				out = append(out, c)
+			}
+			i++
+			continue
+		}
+		// Handle multi-byte Unicode.
+		r, n := utf8.DecodeRune(in[i:])
+		out = utf8.AppendRune(out, foldRune(r))
+		i += n
+	}
+	return out
+}
+
+// foldRune is a variation on unicode.SimpleFold that returns the same rune
+// for all runes in the same fold set.
+//
+// Invariant:
+//
+//	foldRune(x) == foldRune(y) ⇔ strings.EqualFold(string(x), string(y))
+func foldRune(r rune) rune {
+	for {
+		r2 := unicode.SimpleFold(r)
+		if r2 <= r {
+			return r2 // smallest character in the fold set
+		}
+		r = r2
+	}
+}

vendor/github.com/go-json-experiment/json/intern.go

@@ -0,0 +1,86 @@
+// Copyright 2022 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 json
+
+import (
+	"encoding/binary"
+	"math/bits"
+)
+
+// stringCache is a cache for strings converted from a []byte.
+type stringCache = [256]string // 256*unsafe.Sizeof(string("")) => 4KiB
+
+// makeString returns the string form of b.
+// It returns a pre-allocated string from c if present, otherwise
+// it allocates a new string, inserts it into the cache, and returns it.
+func makeString(c *stringCache, b []byte) string {
+	const (
+		minCachedLen = 2   // single byte strings are already interned by the runtime
+		maxCachedLen = 256 // large enough for UUIDs, IPv6 addresses, SHA-256 checksums, etc.
+	)
+	if c == nil || len(b) < minCachedLen || len(b) > maxCachedLen {
+		return string(b)
+	}
+
+	// Compute a hash from the fixed-width prefix and suffix of the string.
+	// This ensures hashing a string is a constant time operation.
+	var h uint32
+	switch {
+	case len(b) >= 8:
+		lo := binary.LittleEndian.Uint64(b[:8])
+		hi := binary.LittleEndian.Uint64(b[len(b)-8:])
+		h = hash64(uint32(lo), uint32(lo>>32)) ^ hash64(uint32(hi), uint32(hi>>32))
+	case len(b) >= 4:
+		lo := binary.LittleEndian.Uint32(b[:4])
+		hi := binary.LittleEndian.Uint32(b[len(b)-4:])
+		h = hash64(lo, hi)
+	case len(b) >= 2:
+		lo := binary.LittleEndian.Uint16(b[:2])
+		hi := binary.LittleEndian.Uint16(b[len(b)-2:])
+		h = hash64(uint32(lo), uint32(hi))
+	}
+
+	// Check the cache for the string.
+	i := h % uint32(len(*c))
+	if s := (*c)[i]; s == string(b) {
+		return s
+	}
+	s := string(b)
+	(*c)[i] = s
+	return s
+}
+
+// hash64 returns the hash of two uint32s as a single uint32.
+func hash64(lo, hi uint32) uint32 {
+	// If avalanche=true, this is identical to XXH32 hash on a 8B string:
+	//	var b [8]byte
+	//	binary.LittleEndian.PutUint32(b[:4], lo)
+	//	binary.LittleEndian.PutUint32(b[4:], hi)
+	//	return xxhash.Sum32(b[:])
+	const (
+		prime1 = 0x9e3779b1
+		prime2 = 0x85ebca77
+		prime3 = 0xc2b2ae3d
+		prime4 = 0x27d4eb2f
+		prime5 = 0x165667b1
+	)
+	h := prime5 + uint32(8)
+	h += lo * prime3
+	h = bits.RotateLeft32(h, 17) * prime4
+	h += hi * prime3
+	h = bits.RotateLeft32(h, 17) * prime4
+	// Skip final mix (avalanche) step of XXH32 for performance reasons.
+	// Empirical testing shows that the improvements in unbiased distribution
+	// does not outweigh the extra cost in computational complexity.
+	const avalanche = false
+	if avalanche {
+		h ^= h >> 15
+		h *= prime2
+		h ^= h >> 13
+		h *= prime3
+		h ^= h >> 16
+	}
+	return h
+}

vendor/github.com/go-json-experiment/json/internal/internal.go

@@ -0,0 +1,14 @@
+// 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.
+
+package internal
+
+// NotForPublicUse is a marker type that an API is for internal use only.
+// It does not perfectly prevent usage of that API, but helps to restrict usage.
+// Anything with this marker is not covered by the Go compatibility agreement.
+type NotForPublicUse struct{}
+
+// AllowInternalUse is passed from "json" to "jsontext" to authenticate
+// that the caller can have access to internal functionality.
+var AllowInternalUse NotForPublicUse

vendor/github.com/go-json-experiment/json/internal/jsonflags/flags.go

@@ -0,0 +1,184 @@
+// 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"
+//   - (Expand | Indent | 1) means "Expand 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 |
+		Deterministic |
+		FormatNilMapAsNull |
+		FormatNilSliceAsNull |
+		MatchCaseInsensitiveNames |
+		FormatByteArrayAsArray |
+		FormatTimeDurationAsNanosecond |
+		IgnoreStructErrors |
+		MatchCaseSensitiveDelimiter |
+		MergeWithLegacySemantics |
+		OmitEmptyWithLegacyDefinition |
+		RejectFloatOverflow |
+		ReportLegacyErrorValues |
+		SkipUnaddressableMethods |
+		StringifyWithLegacySemantics |
+		UnmarshalArrayFromAnyLength
+)
+
+// 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; for internal use by jsontext.Value.Canonicalize
+	CanonicalizeNumbers // encode only; for internal use by jsontext.Value.Canonicalize
+	EscapeForHTML       // encode only
+	EscapeForJS         // encode only
+	Expand              // 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
+	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
+
+	FormatByteArrayAsArray         // marshal or unmarshal
+	FormatTimeDurationAsNanosecond // marshal or unmarshal
+	IgnoreStructErrors             // marshal or unmarshal
+	MatchCaseSensitiveDelimiter    // marshal or unmarshal
+	MergeWithLegacySemantics       // unmarshal
+	OmitEmptyWithLegacyDefinition  // marshal
+	RejectFloatOverflow            // unmarshal
+	ReportLegacyErrorValues        // marshal or unmarshal
+	SkipUnaddressableMethods       // marshal or unmarshal
+	StringifyWithLegacySemantics   // marshal or unmarshal
+	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
+}

vendor/github.com/go-json-experiment/json/internal/jsonopts/options.go

@@ -0,0 +1,190 @@
+// 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.
+
+package jsonopts
+
+import (
+	"github.com/go-json-experiment/json/internal"
+	"github.com/go-json-experiment/json/internal/jsonflags"
+)
+
+// Options is the common options type shared across json packages.
+type Options interface {
+	// JSONOptions is exported so related json packages can implement Options.
+	JSONOptions(internal.NotForPublicUse)
+}
+
+// Struct is the combination of all options in struct form.
+// This is efficient to pass down the call stack and to query.
+type Struct struct {
+	Flags jsonflags.Flags
+
+	CoderValues
+	ArshalValues
+}
+
+type CoderValues struct {
+	Indent       string // jsonflags.Indent
+	IndentPrefix string // jsonflags.IndentPrefix
+	ByteLimit    int64  // jsonflags.ByteLimit
+	DepthLimit   int    // jsonflags.DepthLimit
+}
+
+type ArshalValues struct {
+	// The Marshalers and Unmarshalers fields use the any type to avoid a
+	// concrete dependency on *json.Marshalers and *json.Unmarshalers,
+	// which would in turn create a dependency on the "reflect" package.
+
+	Marshalers   any // jsonflags.Marshalers
+	Unmarshalers any // jsonflags.Unmarshalers
+
+	Format      string
+	FormatDepth int
+}
+
+// DefaultOptionsV2 is the set of all options that define default v2 behavior.
+var DefaultOptionsV2 = Struct{
+	Flags: jsonflags.Flags{
+		Presence: uint64(jsonflags.AllFlags),
+		Values:   uint64(0),
+	},
+	CoderValues: CoderValues{Indent: "\t"}, // Indent is set, but Expand is set to false
+}
+
+// DefaultOptionsV1 is the set of all options that define default v1 behavior.
+var DefaultOptionsV1 = Struct{
+	Flags: jsonflags.Flags{
+		Presence: uint64(jsonflags.AllFlags),
+		Values:   uint64(jsonflags.DefaultV1Flags),
+	},
+	CoderValues: CoderValues{Indent: "\t"}, // Indent is set, but Expand is set to false
+}
+
+// CopyCoderOptions copies coder-specific options from src to dst.
+// This is used by json.MarshalEncode and json.UnmarshalDecode since those
+// functions ignore any coder-specific options and uses the options from the
+// Encoder or Decoder that is passed in.
+func (dst *Struct) CopyCoderOptions(src *Struct) {
+	srcFlags := src.Flags
+	srcFlags.Clear(^jsonflags.AllCoderFlags)
+	dst.Flags.Join(srcFlags)
+	dst.CoderValues = src.CoderValues
+}
+
+func (*Struct) JSONOptions(internal.NotForPublicUse) {}
+
+// GetUnknownOption is injected by the "json" package to handle Options
+// declared in that package so that "jsonopts" can handle them.
+var GetUnknownOption = func(*Struct, Options) (any, bool) { panic("unknown option") }
+
+func GetOption[T any](opts Options, setter func(T) Options) (T, bool) {
+	// Collapse the options to *Struct to simplify lookup.
+	structOpts, ok := opts.(*Struct)
+	if !ok {
+		var structOpts2 Struct
+		structOpts2.Join(opts)
+		structOpts = &structOpts2
+	}
+
+	// Lookup the option based on the return value of the setter.
+	var zero T
+	switch opt := setter(zero).(type) {
+	case jsonflags.Bools:
+		v := structOpts.Flags.Get(opt)
+		ok := structOpts.Flags.Has(opt)
+		return any(v).(T), ok
+	case Indent:
+		if !structOpts.Flags.Has(jsonflags.Indent) {
+			return zero, false
+		}
+		return any(structOpts.Indent).(T), true
+	case IndentPrefix:
+		if !structOpts.Flags.Has(jsonflags.IndentPrefix) {
+			return zero, false
+		}
+		return any(structOpts.IndentPrefix).(T), true
+	case ByteLimit:
+		if !structOpts.Flags.Has(jsonflags.ByteLimit) {
+			return zero, false
+		}
+		return any(structOpts.ByteLimit).(T), true
+	case DepthLimit:
+		if !structOpts.Flags.Has(jsonflags.DepthLimit) {
+			return zero, false
+		}
+		return any(structOpts.DepthLimit).(T), true
+	default:
+		v, ok := GetUnknownOption(structOpts, opt)
+		return v.(T), ok
+	}
+}
+
+// JoinUnknownOption is injected by the "json" package to handle Options
+// declared in that package so that "jsonopts" can handle them.
+var JoinUnknownOption = func(*Struct, Options) { panic("unknown option") }
+
+func (dst *Struct) Join(srcs ...Options) {
+	for _, src := range srcs {
+		switch src := src.(type) {
+		case nil:
+			continue
+		case jsonflags.Bools:
+			dst.Flags.Set(src)
+		case Indent:
+			dst.Flags.Set(jsonflags.Expand | jsonflags.Indent | 1)
+			dst.Indent = string(src)
+		case IndentPrefix:
+			dst.Flags.Set(jsonflags.Expand | jsonflags.IndentPrefix | 1)
+			dst.IndentPrefix = string(src)
+		case ByteLimit:
+			dst.Flags.Set(jsonflags.ByteLimit | 1)
+			dst.ByteLimit = int64(src)
+		case DepthLimit:
+			dst.Flags.Set(jsonflags.DepthLimit | 1)
+			dst.DepthLimit = int(src)
+		case *Struct:
+			dst.Flags.Join(src.Flags)
+			if src.Flags.Has(jsonflags.NonBooleanFlags) {
+				if src.Flags.Has(jsonflags.Indent) {
+					dst.Indent = src.Indent
+				}
+				if src.Flags.Has(jsonflags.IndentPrefix) {
+					dst.IndentPrefix = src.IndentPrefix
+				}
+				if src.Flags.Has(jsonflags.ByteLimit) {
+					dst.ByteLimit = src.ByteLimit
+				}
+				if src.Flags.Has(jsonflags.DepthLimit) {
+					dst.DepthLimit = src.DepthLimit
+				}
+				if src.Flags.Has(jsonflags.Marshalers) {
+					dst.Marshalers = src.Marshalers
+				}
+				if src.Flags.Has(jsonflags.Unmarshalers) {
+					dst.Unmarshalers = src.Unmarshalers
+				}
+			}
+			if src.Format != "" {
+				dst.Format = src.Format
+				dst.FormatDepth = src.FormatDepth
+			}
+		default:
+			JoinUnknownOption(dst, src)
+		}
+	}
+}
+
+type (
+	Indent       string // jsontext.WithIndent
+	IndentPrefix string // jsontext.WithIndentPrefix
+	ByteLimit    int64  // jsontext.WithByteLimit
+	DepthLimit   int    // jsontext.WithDepthLimit
+	// type for jsonflags.Marshalers declared in "json" package
+	// type for jsonflags.Unmarshalers declared in "json" package
+)
+
+func (Indent) JSONOptions(internal.NotForPublicUse)       {}
+func (IndentPrefix) JSONOptions(internal.NotForPublicUse) {}
+func (ByteLimit) JSONOptions(internal.NotForPublicUse)    {}
+func (DepthLimit) JSONOptions(internal.NotForPublicUse)   {}

vendor/github.com/go-json-experiment/json/internal/jsonwire/decode.go

@@ -0,0 +1,640 @@
+// 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.
+
+package jsonwire
+
+import (
+	"io"
+	"math"
+	"slices"
+	"strconv"
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+type ValueFlags uint
+
+const (
+	_ ValueFlags = (1 << iota) / 2 // powers of two starting with zero
+
+	stringNonVerbatim  // string cannot be naively treated as valid UTF-8
+	stringNonCanonical // string not formatted according to RFC 8785, section 3.2.2.2.
+	// TODO: Track whether a number is a non-integer?
+)
+
+func (f *ValueFlags) Join(f2 ValueFlags) { *f |= f2 }
+func (f ValueFlags) IsVerbatim() bool    { return f&stringNonVerbatim == 0 }
+func (f ValueFlags) IsCanonical() bool   { return f&stringNonCanonical == 0 }
+
+// ConsumeWhitespace consumes leading JSON whitespace per RFC 7159, section 2.
+func ConsumeWhitespace(b []byte) (n int) {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	for len(b) > n && (b[n] == ' ' || b[n] == '\t' || b[n] == '\r' || b[n] == '\n') {
+		n++
+	}
+	return n
+}
+
+// ConsumeNull consumes the next JSON null literal per RFC 7159, section 3.
+// It returns 0 if it is invalid, in which case consumeLiteral should be used.
+func ConsumeNull(b []byte) int {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	const literal = "null"
+	if len(b) >= len(literal) && string(b[:len(literal)]) == literal {
+		return len(literal)
+	}
+	return 0
+}
+
+// ConsumeFalse consumes the next JSON false literal per RFC 7159, section 3.
+// It returns 0 if it is invalid, in which case consumeLiteral should be used.
+func ConsumeFalse(b []byte) int {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	const literal = "false"
+	if len(b) >= len(literal) && string(b[:len(literal)]) == literal {
+		return len(literal)
+	}
+	return 0
+}
+
+// ConsumeTrue consumes the next JSON true literal per RFC 7159, section 3.
+// It returns 0 if it is invalid, in which case consumeLiteral should be used.
+func ConsumeTrue(b []byte) int {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	const literal = "true"
+	if len(b) >= len(literal) && string(b[:len(literal)]) == literal {
+		return len(literal)
+	}
+	return 0
+}
+
+// ConsumeLiteral consumes the next JSON literal per RFC 7159, section 3.
+// If the input appears truncated, it returns io.ErrUnexpectedEOF.
+func ConsumeLiteral(b []byte, lit string) (n int, err error) {
+	for i := 0; i < len(b) && i < len(lit); i++ {
+		if b[i] != lit[i] {
+			return i, NewInvalidCharacterError(b[i:], "within literal "+lit+" (expecting "+strconv.QuoteRune(rune(lit[i]))+")")
+		}
+	}
+	if len(b) < len(lit) {
+		return len(b), io.ErrUnexpectedEOF
+	}
+	return len(lit), nil
+}
+
+// ConsumeSimpleString consumes the next JSON string per RFC 7159, section 7
+// but is limited to the grammar for an ASCII string without escape sequences.
+// It returns 0 if it is invalid or more complicated than a simple string,
+// in which case consumeString should be called.
+//
+// It rejects '<', '>', and '&' for compatibility reasons since these were
+// always escaped in the v1 implementation. Thus, if this function reports
+// non-zero then we know that the string would be encoded the same way
+// under both v1 or v2 escape semantics.
+func ConsumeSimpleString(b []byte) (n int) {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	if len(b) > 0 && b[0] == '"' {
+		n++
+		for len(b) > n && b[n] < utf8.RuneSelf && escapeASCII[b[n]] == 0 {
+			n++
+		}
+		if uint(len(b)) > uint(n) && b[n] == '"' {
+			n++
+			return n
+		}
+	}
+	return 0
+}
+
+// ConsumeString consumes the next JSON string per RFC 7159, section 7.
+// If validateUTF8 is false, then this allows the presence of invalid UTF-8
+// characters within the string itself.
+// It reports the number of bytes consumed and whether an error was encountered.
+// If the input appears truncated, it returns io.ErrUnexpectedEOF.
+func ConsumeString(flags *ValueFlags, b []byte, validateUTF8 bool) (n int, err error) {
+	return ConsumeStringResumable(flags, b, 0, validateUTF8)
+}
+
+// ConsumeStringResumable is identical to consumeString but supports resuming
+// from a previous call that returned io.ErrUnexpectedEOF.
+func ConsumeStringResumable(flags *ValueFlags, b []byte, resumeOffset int, validateUTF8 bool) (n int, err error) {
+	// Consume the leading double quote.
+	switch {
+	case resumeOffset > 0:
+		n = resumeOffset // already handled the leading quote
+	case uint(len(b)) == 0:
+		return n, io.ErrUnexpectedEOF
+	case b[0] == '"':
+		n++
+	default:
+		return n, NewInvalidCharacterError(b[n:], `at start of string (expecting '"')`)
+	}
+
+	// Consume every character in the string.
+	for uint(len(b)) > uint(n) {
+		// Optimize for long sequences of unescaped characters.
+		noEscape := func(c byte) bool {
+			return c < utf8.RuneSelf && ' ' <= c && c != '\\' && c != '"'
+		}
+		for uint(len(b)) > uint(n) && noEscape(b[n]) {
+			n++
+		}
+		if uint(len(b)) <= uint(n) {
+			return n, io.ErrUnexpectedEOF
+		}
+
+		// Check for terminating double quote.
+		if b[n] == '"' {
+			n++
+			return n, nil
+		}
+
+		switch r, rn := utf8.DecodeRune(b[n:]); {
+		// Handle UTF-8 encoded byte sequence.
+		// Due to specialized handling of ASCII above, we know that
+		// all normal sequences at this point must be 2 bytes or larger.
+		case rn > 1:
+			n += rn
+		// Handle escape sequence.
+		case r == '\\':
+			flags.Join(stringNonVerbatim)
+			resumeOffset = n
+			if uint(len(b)) < uint(n+2) {
+				return resumeOffset, io.ErrUnexpectedEOF
+			}
+			switch r := b[n+1]; r {
+			case '/':
+				// Forward slash is the only character with 3 representations.
+				// Per RFC 8785, section 3.2.2.2., this must not be escaped.
+				flags.Join(stringNonCanonical)
+				n += 2
+			case '"', '\\', 'b', 'f', 'n', 'r', 't':
+				n += 2
+			case 'u':
+				if uint(len(b)) < uint(n+6) {
+					if hasEscapedUTF16Prefix(b[n:], false) {
+						return resumeOffset, io.ErrUnexpectedEOF
+					}
+					flags.Join(stringNonCanonical)
+					return n, NewInvalidEscapeSequenceError(b[n:])
+				}
+				v1, ok := parseHexUint16(b[n+2 : n+6])
+				if !ok {
+					flags.Join(stringNonCanonical)
+					return n, NewInvalidEscapeSequenceError(b[n : n+6])
+				}
+				// Only certain control characters can use the \uFFFF notation
+				// for canonical formatting (per RFC 8785, section 3.2.2.2.).
+				switch v1 {
+				// \uFFFF notation not permitted for these characters.
+				case '\b', '\f', '\n', '\r', '\t':
+					flags.Join(stringNonCanonical)
+				default:
+					// \uFFFF notation only permitted for control characters.
+					if v1 >= ' ' {
+						flags.Join(stringNonCanonical)
+					} else {
+						// \uFFFF notation must be lower case.
+						for _, c := range b[n+2 : n+6] {
+							if 'A' <= c && c <= 'F' {
+								flags.Join(stringNonCanonical)
+							}
+						}
+					}
+				}
+				n += 6
+
+				r := rune(v1)
+				if validateUTF8 && utf16.IsSurrogate(r) {
+					if uint(len(b)) < uint(n+6) {
+						if hasEscapedUTF16Prefix(b[n:], true) {
+							return resumeOffset, io.ErrUnexpectedEOF
+						}
+						flags.Join(stringNonCanonical)
+						return n - 6, NewInvalidEscapeSequenceError(b[n-6:])
+					} else if v2, ok := parseHexUint16(b[n+2 : n+6]); b[n] != '\\' || b[n+1] != 'u' || !ok {
+						flags.Join(stringNonCanonical)
+						return n - 6, NewInvalidEscapeSequenceError(b[n-6 : n+6])
+					} else if r = utf16.DecodeRune(rune(v1), rune(v2)); r == utf8.RuneError {
+						flags.Join(stringNonCanonical)
+						return n - 6, NewInvalidEscapeSequenceError(b[n-6 : n+6])
+					} else {
+						n += 6
+					}
+				}
+			default:
+				flags.Join(stringNonCanonical)
+				return n, NewInvalidEscapeSequenceError(b[n : n+2])
+			}
+		// Handle invalid UTF-8.
+		case r == utf8.RuneError:
+			if !utf8.FullRune(b[n:]) {
+				return n, io.ErrUnexpectedEOF
+			}
+			flags.Join(stringNonVerbatim | stringNonCanonical)
+			if validateUTF8 {
+				return n, ErrInvalidUTF8
+			}
+			n++
+		// Handle invalid control characters.
+		case r < ' ':
+			flags.Join(stringNonVerbatim | stringNonCanonical)
+			return n, NewInvalidCharacterError(b[n:], "within string (expecting non-control character)")
+		default:
+			panic("BUG: unhandled character " + QuoteRune(b[n:]))
+		}
+	}
+	return n, io.ErrUnexpectedEOF
+}
+
+// AppendUnquote appends the unescaped form of a JSON string in src to dst.
+// Any invalid UTF-8 within the string will be replaced with utf8.RuneError,
+// but the error will be specified as having encountered such an error.
+// The input must be an entire JSON string with no surrounding whitespace.
+func AppendUnquote[Bytes ~[]byte | ~string](dst []byte, src Bytes) (v []byte, err error) {
+	dst = slices.Grow(dst, len(src))
+
+	// Consume the leading double quote.
+	var i, n int
+	switch {
+	case uint(len(src)) == 0:
+		return dst, io.ErrUnexpectedEOF
+	case src[0] == '"':
+		i, n = 1, 1
+	default:
+		return dst, NewInvalidCharacterError(src, `at start of string (expecting '"')`)
+	}
+
+	// Consume every character in the string.
+	for uint(len(src)) > uint(n) {
+		// Optimize for long sequences of unescaped characters.
+		noEscape := func(c byte) bool {
+			return c < utf8.RuneSelf && ' ' <= c && c != '\\' && c != '"'
+		}
+		for uint(len(src)) > uint(n) && noEscape(src[n]) {
+			n++
+		}
+		if uint(len(src)) <= uint(n) {
+			dst = append(dst, src[i:n]...)
+			return dst, io.ErrUnexpectedEOF
+		}
+
+		// Check for terminating double quote.
+		if src[n] == '"' {
+			dst = append(dst, src[i:n]...)
+			n++
+			if n < len(src) {
+				err = NewInvalidCharacterError(src[n:], "after string value")
+			}
+			return dst, err
+		}
+
+		switch r, rn := utf8.DecodeRuneInString(string(truncateMaxUTF8(src[n:]))); {
+		// Handle UTF-8 encoded byte sequence.
+		// Due to specialized handling of ASCII above, we know that
+		// all normal sequences at this point must be 2 bytes or larger.
+		case rn > 1:
+			n += rn
+		// Handle escape sequence.
+		case r == '\\':
+			dst = append(dst, src[i:n]...)
+
+			// Handle escape sequence.
+			if uint(len(src)) < uint(n+2) {
+				return dst, io.ErrUnexpectedEOF
+			}
+			switch r := src[n+1]; r {
+			case '"', '\\', '/':
+				dst = append(dst, r)
+				n += 2
+			case 'b':
+				dst = append(dst, '\b')
+				n += 2
+			case 'f':
+				dst = append(dst, '\f')
+				n += 2
+			case 'n':
+				dst = append(dst, '\n')
+				n += 2
+			case 'r':
+				dst = append(dst, '\r')
+				n += 2
+			case 't':
+				dst = append(dst, '\t')
+				n += 2
+			case 'u':
+				if uint(len(src)) < uint(n+6) {
+					if hasEscapedUTF16Prefix(src[n:], false) {
+						return dst, io.ErrUnexpectedEOF
+					}
+					return dst, NewInvalidEscapeSequenceError(src[n:])
+				}
+				v1, ok := parseHexUint16(src[n+2 : n+6])
+				if !ok {
+					return dst, NewInvalidEscapeSequenceError(src[n : n+6])
+				}
+				n += 6
+
+				// Check whether this is a surrogate half.
+				r := rune(v1)
+				if utf16.IsSurrogate(r) {
+					r = utf8.RuneError // assume failure unless the following succeeds
+					if uint(len(src)) < uint(n+6) {
+						if hasEscapedUTF16Prefix(src[n:], true) {
+							return utf8.AppendRune(dst, r), io.ErrUnexpectedEOF
+						}
+						err = NewInvalidEscapeSequenceError(src[n-6:])
+					} else if v2, ok := parseHexUint16(src[n+2 : n+6]); src[n] != '\\' || src[n+1] != 'u' || !ok {
+						err = NewInvalidEscapeSequenceError(src[n-6 : n+6])
+					} else if r = utf16.DecodeRune(rune(v1), rune(v2)); r == utf8.RuneError {
+						err = NewInvalidEscapeSequenceError(src[n-6 : n+6])
+					} else {
+						n += 6
+					}
+				}
+
+				dst = utf8.AppendRune(dst, r)
+			default:
+				return dst, NewInvalidEscapeSequenceError(src[n : n+2])
+			}
+			i = n
+		// Handle invalid UTF-8.
+		case r == utf8.RuneError:
+			dst = append(dst, src[i:n]...)
+			if !utf8.FullRuneInString(string(truncateMaxUTF8(src[n:]))) {
+				return dst, io.ErrUnexpectedEOF
+			}
+			// NOTE: An unescaped string may be longer than the escaped string
+			// because invalid UTF-8 bytes are being replaced.
+			dst = append(dst, "\uFFFD"...)
+			n += rn
+			i = n
+			err = ErrInvalidUTF8
+		// Handle invalid control characters.
+		case r < ' ':
+			dst = append(dst, src[i:n]...)
+			return dst, NewInvalidCharacterError(src[n:], "within string (expecting non-control character)")
+		default:
+			panic("BUG: unhandled character " + QuoteRune(src[n:]))
+		}
+	}
+	dst = append(dst, src[i:n]...)
+	return dst, io.ErrUnexpectedEOF
+}
+
+// hasEscapedUTF16Prefix reports whether b is possibly
+// the truncated prefix of a \uFFFF escape sequence.
+func hasEscapedUTF16Prefix[Bytes ~[]byte | ~string](b Bytes, lowerSurrogateHalf bool) bool {
+	for i := 0; i < len(b); i++ {
+		switch c := b[i]; {
+		case i == 0 && c != '\\':
+			return false
+		case i == 1 && c != 'u':
+			return false
+		case i == 2 && lowerSurrogateHalf && c != 'd' && c != 'D':
+			return false // not within ['\uDC00':'\uDFFF']
+		case i == 3 && lowerSurrogateHalf && !('c' <= c && c <= 'f') && !('C' <= c && c <= 'F'):
+			return false // not within ['\uDC00':'\uDFFF']
+		case i >= 2 && i < 6 && !('0' <= c && c <= '9') && !('a' <= c && c <= 'f') && !('A' <= c && c <= 'F'):
+			return false
+		}
+	}
+	return true
+}
+
+// UnquoteMayCopy returns the unescaped form of b.
+// If there are no escaped characters, the output is simply a subslice of
+// the input with the surrounding quotes removed.
+// Otherwise, a new buffer is allocated for the output.
+// It assumes the input is valid.
+func UnquoteMayCopy(b []byte, isVerbatim bool) []byte {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	if isVerbatim {
+		return b[len(`"`) : len(b)-len(`"`)]
+	}
+	b, _ = AppendUnquote(nil, b)
+	return b
+}
+
+// ConsumeSimpleNumber consumes the next JSON number per RFC 7159, section 6
+// but is limited to the grammar for a positive integer.
+// It returns 0 if it is invalid or more complicated than a simple integer,
+// in which case consumeNumber should be called.
+func ConsumeSimpleNumber(b []byte) (n int) {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	if len(b) > 0 {
+		if b[0] == '0' {
+			n++
+		} else if '1' <= b[0] && b[0] <= '9' {
+			n++
+			for len(b) > n && ('0' <= b[n] && b[n] <= '9') {
+				n++
+			}
+		} else {
+			return 0
+		}
+		if uint(len(b)) <= uint(n) || (b[n] != '.' && b[n] != 'e' && b[n] != 'E') {
+			return n
+		}
+	}
+	return 0
+}
+
+type ConsumeNumberState uint
+
+const (
+	consumeNumberInit ConsumeNumberState = iota
+	beforeIntegerDigits
+	withinIntegerDigits
+	beforeFractionalDigits
+	withinFractionalDigits
+	beforeExponentDigits
+	withinExponentDigits
+)
+
+// ConsumeNumber consumes the next JSON number per RFC 7159, section 6.
+// It reports the number of bytes consumed and whether an error was encountered.
+// If the input appears truncated, it returns io.ErrUnexpectedEOF.
+//
+// Note that JSON numbers are not self-terminating.
+// If the entire input is consumed, then the caller needs to consider whether
+// there may be subsequent unread data that may still be part of this number.
+func ConsumeNumber(b []byte) (n int, err error) {
+	n, _, err = ConsumeNumberResumable(b, 0, consumeNumberInit)
+	return n, err
+}
+
+// ConsumeNumberResumable is identical to consumeNumber but supports resuming
+// from a previous call that returned io.ErrUnexpectedEOF.
+func ConsumeNumberResumable(b []byte, resumeOffset int, state ConsumeNumberState) (n int, _ ConsumeNumberState, err error) {
+	// Jump to the right state when resuming from a partial consumption.
+	n = resumeOffset
+	if state > consumeNumberInit {
+		switch state {
+		case withinIntegerDigits, withinFractionalDigits, withinExponentDigits:
+			// Consume leading digits.
+			for uint(len(b)) > uint(n) && ('0' <= b[n] && b[n] <= '9') {
+				n++
+			}
+			if uint(len(b)) <= uint(n) {
+				return n, state, nil // still within the same state
+			}
+			state++ // switches "withinX" to "beforeY" where Y is the state after X
+		}
+		switch state {
+		case beforeIntegerDigits:
+			goto beforeInteger
+		case beforeFractionalDigits:
+			goto beforeFractional
+		case beforeExponentDigits:
+			goto beforeExponent
+		default:
+			return n, state, nil
+		}
+	}
+
+	// Consume required integer component (with optional minus sign).
+beforeInteger:
+	resumeOffset = n
+	if uint(len(b)) > 0 && b[0] == '-' {
+		n++
+	}
+	switch {
+	case uint(len(b)) <= uint(n):
+		return resumeOffset, beforeIntegerDigits, io.ErrUnexpectedEOF
+	case b[n] == '0':
+		n++
+		state = beforeFractionalDigits
+	case '1' <= b[n] && b[n] <= '9':
+		n++
+		for uint(len(b)) > uint(n) && ('0' <= b[n] && b[n] <= '9') {
+			n++
+		}
+		state = withinIntegerDigits
+	default:
+		return n, state, NewInvalidCharacterError(b[n:], "within number (expecting digit)")
+	}
+
+	// Consume optional fractional component.
+beforeFractional:
+	if uint(len(b)) > uint(n) && b[n] == '.' {
+		resumeOffset = n
+		n++
+		switch {
+		case uint(len(b)) <= uint(n):
+			return resumeOffset, beforeFractionalDigits, io.ErrUnexpectedEOF
+		case '0' <= b[n] && b[n] <= '9':
+			n++
+		default:
+			return n, state, NewInvalidCharacterError(b[n:], "within number (expecting digit)")
+		}
+		for uint(len(b)) > uint(n) && ('0' <= b[n] && b[n] <= '9') {
+			n++
+		}
+		state = withinFractionalDigits
+	}
+
+	// Consume optional exponent component.
+beforeExponent:
+	if uint(len(b)) > uint(n) && (b[n] == 'e' || b[n] == 'E') {
+		resumeOffset = n
+		n++
+		if uint(len(b)) > uint(n) && (b[n] == '-' || b[n] == '+') {
+			n++
+		}
+		switch {
+		case uint(len(b)) <= uint(n):
+			return resumeOffset, beforeExponentDigits, io.ErrUnexpectedEOF
+		case '0' <= b[n] && b[n] <= '9':
+			n++
+		default:
+			return n, state, NewInvalidCharacterError(b[n:], "within number (expecting digit)")
+		}
+		for uint(len(b)) > uint(n) && ('0' <= b[n] && b[n] <= '9') {
+			n++
+		}
+		state = withinExponentDigits
+	}
+
+	return n, state, nil
+}
+
+// parseHexUint16 is similar to strconv.ParseUint,
+// but operates directly on []byte and is optimized for base-16.
+// See https://go.dev/issue/42429.
+func parseHexUint16[Bytes ~[]byte | ~string](b Bytes) (v uint16, ok bool) {
+	if len(b) != 4 {
+		return 0, false
+	}
+	for i := 0; i < 4; i++ {
+		c := b[i]
+		switch {
+		case '0' <= c && c <= '9':
+			c = c - '0'
+		case 'a' <= c && c <= 'f':
+			c = 10 + c - 'a'
+		case 'A' <= c && c <= 'F':
+			c = 10 + c - 'A'
+		default:
+			return 0, false
+		}
+		v = v*16 + uint16(c)
+	}
+	return v, true
+}
+
+// ParseUint parses b as a decimal unsigned integer according to
+// a strict subset of the JSON number grammar, returning the value if valid.
+// It returns (0, false) if there is a syntax error and
+// returns (math.MaxUint64, false) if there is an overflow.
+func ParseUint(b []byte) (v uint64, ok bool) {
+	const unsafeWidth = 20 // len(fmt.Sprint(uint64(math.MaxUint64)))
+	var n int
+	for ; len(b) > n && ('0' <= b[n] && b[n] <= '9'); n++ {
+		v = 10*v + uint64(b[n]-'0')
+	}
+	switch {
+	case n == 0 || len(b) != n || (b[0] == '0' && string(b) != "0"):
+		return 0, false
+	case n >= unsafeWidth && (b[0] != '1' || v < 1e19 || n > unsafeWidth):
+		return math.MaxUint64, false
+	}
+	return v, true
+}
+
+// ParseFloat parses a floating point number according to the Go float grammar.
+// Note that the JSON number grammar is a strict subset.
+//
+// If the number overflows the finite representation of a float,
+// then we return MaxFloat since any finite value will always be infinitely
+// more accurate at representing another finite value than an infinite value.
+func ParseFloat(b []byte, bits int) (v float64, ok bool) {
+	// Fast path for exact integer numbers which fit in the
+	// 24-bit or 53-bit significand of a float32 or float64.
+	var negLen int // either 0 or 1
+	if len(b) > 0 && b[0] == '-' {
+		negLen = 1
+	}
+	u, ok := ParseUint(b[negLen:])
+	if ok && ((bits == 32 && u <= 1<<24) || (bits == 64 && u <= 1<<53)) {
+		return math.Copysign(float64(u), float64(-1*negLen)), true
+	}
+
+	// Note that the []byte->string conversion unfortunately allocates.
+	// See https://go.dev/issue/42429 for more information.
+	fv, err := strconv.ParseFloat(string(b), bits)
+	if math.IsInf(fv, 0) {
+		switch {
+		case bits == 32 && math.IsInf(fv, +1):
+			fv = +math.MaxFloat32
+		case bits == 64 && math.IsInf(fv, +1):
+			fv = +math.MaxFloat64
+		case bits == 32 && math.IsInf(fv, -1):
+			fv = -math.MaxFloat32
+		case bits == 64 && math.IsInf(fv, -1):
+			fv = -math.MaxFloat64
+		}
+	}
+	return fv, err == nil
+}

vendor/github.com/go-json-experiment/json/internal/jsonwire/encode.go

@@ -0,0 +1,234 @@
+// 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.
+
+package jsonwire
+
+import (
+	"math"
+	"slices"
+	"strconv"
+	"unicode/utf16"
+	"unicode/utf8"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+)
+
+// escapeASCII reports whether the ASCII character needs to be escaped.
+// It conservatively assumes EscapeForHTML.
+var escapeASCII = [...]uint8{
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // escape control characters
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // escape control characters
+	0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, // escape '"' and '&'
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, // escape '<' and '>'
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, // escape '\\'
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+}
+
+// NeedEscape reports whether src needs escaping of any characters.
+// It conservatively assumes EscapeForHTML and EscapeForJS.
+// It reports true for inputs with invalid UTF-8.
+func NeedEscape[Bytes ~[]byte | ~string](src Bytes) bool {
+	var i int
+	for uint(len(src)) > uint(i) {
+		if c := src[i]; c < utf8.RuneSelf {
+			if escapeASCII[c] > 0 {
+				return true
+			}
+			i++
+		} else {
+			r, rn := utf8.DecodeRuneInString(string(truncateMaxUTF8(src[i:])))
+			if r == utf8.RuneError || r == '\u2028' || r == '\u2029' {
+				return true
+			}
+			i += rn
+		}
+	}
+	return false
+}
+
+// AppendQuote appends src to dst as a JSON string per RFC 7159, section 7.
+//
+// It takes in flags and respects the following:
+//   - EscapeForHTML escapes '<', '>', and '&'.
+//   - EscapeForJS escapes '\u2028' and '\u2029'.
+//   - AllowInvalidUTF8 avoids reporting an error for invalid UTF-8.
+//
+// Regardless of whether AllowInvalidUTF8 is specified,
+// invalid bytes are replaced with the Unicode replacement character ('\ufffd').
+// If no escape flags are set, then the shortest representable form is used,
+// which is also the canonical form for strings (RFC 8785, section 3.2.2.2).
+func AppendQuote[Bytes ~[]byte | ~string](dst []byte, src Bytes, flags *jsonflags.Flags) ([]byte, error) {
+	var i, n int
+	var hasInvalidUTF8 bool
+	dst = slices.Grow(dst, len(`"`)+len(src)+len(`"`))
+	dst = append(dst, '"')
+	for uint(len(src)) > uint(n) {
+		// Handle single-byte ASCII.
+		if c := src[n]; c < utf8.RuneSelf {
+			n++
+			if escapeASCII[c] > 0 {
+				if (c == '<' || c == '>' || c == '&') && !flags.Get(jsonflags.EscapeForHTML) {
+					continue
+				}
+				dst = append(dst, src[i:n-1]...)
+				dst = appendEscapedASCII(dst, c)
+				i = n
+			}
+			continue
+		}
+
+		// Handle multi-byte Unicode.
+		switch r, rn := utf8.DecodeRuneInString(string(truncateMaxUTF8(src[n:]))); {
+		case r == utf8.RuneError && rn == 1:
+			hasInvalidUTF8 = true
+			dst = append(dst, src[i:n]...)
+			dst = append(dst, "\ufffd"...)
+			n += rn
+			i = n
+		case (r == '\u2028' || r == '\u2029') && flags.Get(jsonflags.EscapeForJS):
+			dst = append(dst, src[i:n]...)
+			dst = appendEscapedUnicode(dst, r)
+			n += rn
+			i = n
+		default:
+			n += rn
+		}
+	}
+	dst = append(dst, src[i:n]...)
+	dst = append(dst, '"')
+	if hasInvalidUTF8 && !flags.Get(jsonflags.AllowInvalidUTF8) {
+		return dst, ErrInvalidUTF8
+	}
+	return dst, nil
+}
+
+func appendEscapedASCII(dst []byte, c byte) []byte {
+	switch c {
+	case '"', '\\':
+		dst = append(dst, '\\', c)
+	case '\b':
+		dst = append(dst, "\\b"...)
+	case '\f':
+		dst = append(dst, "\\f"...)
+	case '\n':
+		dst = append(dst, "\\n"...)
+	case '\r':
+		dst = append(dst, "\\r"...)
+	case '\t':
+		dst = append(dst, "\\t"...)
+	default:
+		dst = appendEscapedUTF16(dst, uint16(c))
+	}
+	return dst
+}
+
+func appendEscapedUnicode(dst []byte, r rune) []byte {
+	if r1, r2 := utf16.EncodeRune(r); r1 != '\ufffd' && r2 != '\ufffd' {
+		dst = appendEscapedUTF16(dst, uint16(r1))
+		dst = appendEscapedUTF16(dst, uint16(r2))
+	} else {
+		dst = appendEscapedUTF16(dst, uint16(r))
+	}
+	return dst
+}
+
+func appendEscapedUTF16(dst []byte, x uint16) []byte {
+	const hex = "0123456789abcdef"
+	return append(dst, '\\', 'u', hex[(x>>12)&0xf], hex[(x>>8)&0xf], hex[(x>>4)&0xf], hex[(x>>0)&0xf])
+}
+
+// ReformatString consumes a JSON string from src and appends it to dst,
+// reformatting it if necessary for the given escapeRune parameter.
+// It returns the appended output and the number of consumed input bytes.
+func ReformatString(dst, src []byte, flags *jsonflags.Flags) ([]byte, int, error) {
+	// TODO: Should this update ValueFlags as input?
+	var valFlags ValueFlags
+	n, err := ConsumeString(&valFlags, src, !flags.Get(jsonflags.AllowInvalidUTF8))
+	if err != nil {
+		return dst, n, err
+	}
+	isCanonical := !flags.Get(jsonflags.EscapeForHTML | jsonflags.EscapeForJS)
+	if flags.Get(jsonflags.PreserveRawStrings) || (isCanonical && valFlags.IsCanonical()) {
+		dst = append(dst, src[:n]...) // copy the string verbatim
+		return dst, n, nil
+	}
+
+	// TODO: Implement a direct, raw-to-raw reformat for strings.
+	// If the escapeRune option would have resulted in no changes to the output,
+	// it would be faster to simply append src to dst without going through
+	// an intermediary representation in a separate buffer.
+	b, _ := AppendUnquote(nil, src[:n])
+	dst, _ = AppendQuote(dst, string(b), flags)
+	return dst, n, nil
+}
+
+// AppendFloat appends src to dst as a JSON number per RFC 7159, section 6.
+// It formats numbers similar to the ES6 number-to-string conversion.
+// See https://go.dev/issue/14135.
+//
+// The output is identical to ECMA-262, 6th edition, section 7.1.12.1 and with
+// RFC 8785, section 3.2.2.3 for 64-bit floating-point numbers except for -0,
+// which is formatted as -0 instead of just 0.
+//
+// For 32-bit floating-point numbers,
+// the output is a 32-bit equivalent of the algorithm.
+// Note that ECMA-262 specifies no algorithm for 32-bit numbers.
+func AppendFloat(dst []byte, src float64, bits int) []byte {
+	if bits == 32 {
+		src = float64(float32(src))
+	}
+
+	abs := math.Abs(src)
+	fmt := byte('f')
+	if abs != 0 {
+		if bits == 64 && (float64(abs) < 1e-6 || float64(abs) >= 1e21) ||
+			bits == 32 && (float32(abs) < 1e-6 || float32(abs) >= 1e21) {
+			fmt = 'e'
+		}
+	}
+	dst = strconv.AppendFloat(dst, src, fmt, -1, bits)
+	if fmt == 'e' {
+		// Clean up e-09 to e-9.
+		n := len(dst)
+		if n >= 4 && dst[n-4] == 'e' && dst[n-3] == '-' && dst[n-2] == '0' {
+			dst[n-2] = dst[n-1]
+			dst = dst[:n-1]
+		}
+	}
+	return dst
+}
+
+// ReformatNumber consumes a JSON string from src and appends it to dst,
+// canonicalizing it if specified.
+// It returns the appended output and the number of consumed input bytes.
+func ReformatNumber(dst, src []byte, canonicalize bool) ([]byte, int, error) {
+	n, err := ConsumeNumber(src)
+	if err != nil {
+		return dst, n, err
+	}
+	if !canonicalize {
+		dst = append(dst, src[:n]...) // copy the number verbatim
+		return dst, n, nil
+	}
+
+	// Canonicalize the number per RFC 8785, section 3.2.2.3.
+	// As an optimization, we can copy integer numbers below 2⁵³ verbatim.
+	const maxExactIntegerDigits = 16 // len(strconv.AppendUint(nil, 1<<53, 10))
+	if n < maxExactIntegerDigits && ConsumeSimpleNumber(src[:n]) == n {
+		dst = append(dst, src[:n]...) // copy the number verbatim
+		return dst, n, nil
+	}
+	fv, _ := strconv.ParseFloat(string(src[:n]), 64)
+	switch {
+	case fv == 0:
+		fv = 0 // normalize negative zero as just zero
+	case math.IsInf(fv, +1):
+		fv = +math.MaxFloat64
+	case math.IsInf(fv, -1):
+		fv = -math.MaxFloat64
+	}
+	return AppendFloat(dst, fv, 64), n, nil
+}

vendor/github.com/go-json-experiment/json/internal/jsonwire/wire.go

@@ -0,0 +1,169 @@
+// 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.
+
+// Package jsonwire implements stateless functionality for handling JSON text.
+package jsonwire
+
+import (
+	"cmp"
+	"errors"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+// TrimSuffixWhitespace trims JSON from the end of b.
+func TrimSuffixWhitespace(b []byte) []byte {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	n := len(b) - 1
+	for n >= 0 && (b[n] == ' ' || b[n] == '\t' || b[n] == '\r' || b[n] == '\n') {
+		n--
+	}
+	return b[:n+1]
+}
+
+// TrimSuffixString trims a valid JSON string at the end of b.
+// The behavior is undefined if there is not a valid JSON string present.
+func TrimSuffixString(b []byte) []byte {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	if len(b) > 0 && b[len(b)-1] == '"' {
+		b = b[:len(b)-1]
+	}
+	for len(b) >= 2 && !(b[len(b)-1] == '"' && b[len(b)-2] != '\\') {
+		b = b[:len(b)-1] // trim all characters except an unescaped quote
+	}
+	if len(b) > 0 && b[len(b)-1] == '"' {
+		b = b[:len(b)-1]
+	}
+	return b
+}
+
+// HasSuffixByte reports whether b ends with c.
+func HasSuffixByte(b []byte, c byte) bool {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	return len(b) > 0 && b[len(b)-1] == c
+}
+
+// TrimSuffixByte removes c from the end of b if it is present.
+func TrimSuffixByte(b []byte, c byte) []byte {
+	// NOTE: The arguments and logic are kept simple to keep this inlinable.
+	if len(b) > 0 && b[len(b)-1] == c {
+		return b[:len(b)-1]
+	}
+	return b
+}
+
+// QuoteRune quotes the first rune in the input.
+func QuoteRune[Bytes ~[]byte | ~string](b Bytes) string {
+	r, n := utf8.DecodeRuneInString(string(truncateMaxUTF8(b)))
+	if r == utf8.RuneError && n == 1 {
+		return `'\x` + strconv.FormatUint(uint64(b[0]), 16) + `'`
+	}
+	return strconv.QuoteRune(r)
+}
+
+// CompareUTF16 lexicographically compares x to y according
+// to the UTF-16 codepoints of the UTF-8 encoded input strings.
+// This implements the ordering specified in RFC 8785, section 3.2.3.
+func CompareUTF16[Bytes ~[]byte | ~string](x, y Bytes) int {
+	// NOTE: This is an optimized, mostly allocation-free implementation
+	// of CompareUTF16Simple in wire_test.go. FuzzCompareUTF16 verifies that the
+	// two implementations agree on the result of comparing any two strings.
+	isUTF16Self := func(r rune) bool {
+		return ('\u0000' <= r && r <= '\uD7FF') || ('\uE000' <= r && r <= '\uFFFF')
+	}
+
+	var invalidUTF8 bool
+	x0, y0 := x, y
+	for {
+		if len(x) == 0 || len(y) == 0 {
+			if len(x) == len(y) && invalidUTF8 {
+				return strings.Compare(string(x0), string(y0))
+			}
+			return cmp.Compare(len(x), len(y))
+		}
+
+		// ASCII fast-path.
+		if x[0] < utf8.RuneSelf || y[0] < utf8.RuneSelf {
+			if x[0] != y[0] {
+				return cmp.Compare(x[0], y[0])
+			}
+			x, y = x[1:], y[1:]
+			continue
+		}
+
+		// Decode next pair of runes as UTF-8.
+		rx, nx := utf8.DecodeRuneInString(string(truncateMaxUTF8(x)))
+		ry, ny := utf8.DecodeRuneInString(string(truncateMaxUTF8(y)))
+
+		selfx := isUTF16Self(rx)
+		selfy := isUTF16Self(ry)
+		switch {
+		// The x rune is a single UTF-16 codepoint, while
+		// the y rune is a surrogate pair of UTF-16 codepoints.
+		case selfx && !selfy:
+			ry, _ = utf16.EncodeRune(ry)
+		// The y rune is a single UTF-16 codepoint, while
+		// the x rune is a surrogate pair of UTF-16 codepoints.
+		case selfy && !selfx:
+			rx, _ = utf16.EncodeRune(rx)
+		}
+		if rx != ry {
+			return cmp.Compare(rx, ry)
+		}
+		invalidUTF8 = invalidUTF8 || (rx == utf8.RuneError && nx == 1) || (ry == utf8.RuneError && ny == 1)
+		x, y = x[nx:], y[ny:]
+	}
+}
+
+// truncateMaxUTF8 truncates b such it contains at least one rune.
+//
+// The utf8 package currently lacks generic variants, which complicates
+// generic functions that operates on either []byte or string.
+// As a hack, we always call the utf8 function operating on strings,
+// but always truncate the input such that the result is identical.
+//
+// Example usage:
+//
+//	utf8.DecodeRuneInString(string(truncateMaxUTF8(b)))
+//
+// Converting a []byte to a string is stack allocated since
+// truncateMaxUTF8 guarantees that the []byte is short.
+func truncateMaxUTF8[Bytes ~[]byte | ~string](b Bytes) Bytes {
+	// TODO(https://go.dev/issue/56948): Remove this function and
+	// instead directly call generic utf8 functions wherever used.
+	if len(b) > utf8.UTFMax {
+		return b[:utf8.UTFMax]
+	}
+	return b
+}
+
+// NewError and ErrInvalidUTF8 are injected by the "jsontext" package,
+// so that these error types use the jsontext.SyntacticError type.
+var (
+	NewError       = errors.New
+	ErrInvalidUTF8 = errors.New("invalid UTF-8 within string")
+)
+
+func NewInvalidCharacterError[Bytes ~[]byte | ~string](prefix Bytes, where string) error {
+	what := QuoteRune(prefix)
+	return NewError("invalid character " + what + " " + where)
+}
+
+func NewInvalidEscapeSequenceError[Bytes ~[]byte | ~string](what Bytes) error {
+	label := "escape sequence"
+	if len(what) > 6 {
+		label = "surrogate pair"
+	}
+	needEscape := strings.IndexFunc(string(what), func(r rune) bool {
+		return r == '`' || r == utf8.RuneError || unicode.IsSpace(r) || !unicode.IsPrint(r)
+	}) >= 0
+	if needEscape {
+		return NewError("invalid " + label + " " + strconv.Quote(string(what)) + " within string")
+	} else {
+		return NewError("invalid " + label + " `" + string(what) + "` within string")
+	}
+}

vendor/github.com/go-json-experiment/json/jsontext/doc.go

@@ -0,0 +1,105 @@
+// 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.
+
+// Package jsontext implements syntactic processing of JSON
+// as specified in RFC 4627, RFC 7159, RFC 7493, RFC 8259, and RFC 8785.
+// JSON is a simple data interchange format that can represent
+// primitive data types such as booleans, strings, and numbers,
+// in addition to structured data types such as objects and arrays.
+//
+// The [Encoder] and [Decoder] types are used to encode or decode
+// a stream of JSON tokens or values.
+//
+// # Tokens and Values
+//
+// A JSON token refers to the basic structural elements of JSON:
+//
+//   - a JSON literal (i.e., null, true, or false)
+//   - a JSON string (e.g., "hello, world!")
+//   - a JSON number (e.g., 123.456)
+//   - a start or end delimiter for a JSON object (i.e., '{' or '}')
+//   - a start or end delimiter for a JSON array (i.e., '[' or ']')
+//
+// A JSON token is represented by the [Token] type in Go. Technically,
+// there are two additional structural characters (i.e., ':' and ','),
+// but there is no [Token] representation for them since their presence
+// can be inferred by the structure of the JSON grammar itself.
+// For example, there must always be an implicit colon between
+// the name and value of a JSON object member.
+//
+// A JSON value refers to a complete unit of JSON data:
+//
+//   - a JSON literal, string, or number
+//   - a JSON object (e.g., `{"name":"value"}`)
+//   - a JSON array (e.g., `[1,2,3,]`)
+//
+// A JSON value is represented by the [Value] type in Go and is a []byte
+// containing the raw textual representation of the value. There is some overlap
+// between tokens and values as both contain literals, strings, and numbers.
+// However, only a value can represent the entirety of a JSON object or array.
+//
+// The [Encoder] and [Decoder] types contain methods to read or write the next
+// [Token] or [Value] in a sequence. They maintain a state machine to validate
+// whether the sequence of JSON tokens and/or values produces a valid JSON.
+// [Options] may be passed to the [NewEncoder] or [NewDecoder] constructors
+// to configure the syntactic behavior of encoding and decoding.
+//
+// # Terminology
+//
+// The terms "encode" and "decode" are used for syntactic functionality
+// that is concerned with processing JSON based on its grammar, and
+// the terms "marshal" and "unmarshal" are used for semantic functionality
+// that determines the meaning of JSON values as Go values and vice-versa.
+// This package (i.e., [jsontext]) deals with JSON at a syntactic layer,
+// while [encoding/json/v2] deals with JSON at a semantic layer.
+// The goal is to provide a clear distinction between functionality that
+// is purely concerned with encoding versus that of marshaling.
+// For example, one can directly encode a stream of JSON tokens without
+// needing to marshal a concrete Go value representing them.
+// Similarly, one can decode a stream of JSON tokens without
+// needing to unmarshal them into a concrete Go value.
+//
+// This package uses JSON terminology when discussing JSON, which may differ
+// from related concepts in Go or elsewhere in computing literature.
+//
+//   - a JSON "object" refers to an unordered collection of name/value members.
+//   - a JSON "array" refers to an ordered sequence of elements.
+//   - a JSON "value" refers to either a literal (i.e., null, false, or true),
+//     string, number, object, or array.
+//
+// See RFC 8259 for more information.
+//
+// # Specifications
+//
+// Relevant specifications include RFC 4627, RFC 7159, RFC 7493, RFC 8259,
+// and RFC 8785. Each RFC is generally a stricter subset of another RFC.
+// In increasing order of strictness:
+//
+//   - RFC 4627 and RFC 7159 do not require (but recommend) the use of UTF-8
+//     and also do not require (but recommend) that object names be unique.
+//   - RFC 8259 requires the use of UTF-8,
+//     but does not require (but recommends) that object names be unique.
+//   - RFC 7493 requires the use of UTF-8
+//     and also requires that object names be unique.
+//   - RFC 8785 defines a canonical representation. It requires the use of UTF-8
+//     and also requires that object names be unique and in a specific ordering.
+//     It specifies exactly how strings and numbers must be formatted.
+//
+// The primary difference between RFC 4627 and RFC 7159 is that the former
+// restricted top-level values to only JSON objects and arrays, while
+// RFC 7159 and subsequent RFCs permit top-level values to additionally be
+// JSON nulls, booleans, strings, or numbers.
+//
+// By default, this package operates on RFC 7493, but can be configured
+// to operate according to the other RFC specifications.
+// RFC 7493 is a stricter subset of RFC 8259 and fully compliant with it.
+// In particular, it makes specific choices about behavior that RFC 8259
+// leaves as undefined in order to ensure greater interoperability.
+package jsontext
+
+// requireKeyedLiterals can be embedded in a struct to require keyed literals.
+type requireKeyedLiterals struct{}
+
+// nonComparable can be embedded in a struct to prevent comparability.
+type nonComparable [0]func()

vendor/github.com/go-json-experiment/json/jsontext/encode.go

@@ -0,0 +1,900 @@
+// 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 jsontext
+
+import (
+	"bytes"
+	"io"
+	"math/bits"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+// Encoder is a streaming encoder from raw JSON tokens and values.
+// It is used to write a stream of top-level JSON values,
+// each terminated with a newline character.
+//
+// [Encoder.WriteToken] and [Encoder.WriteValue] calls may be interleaved.
+// For example, the following JSON value:
+//
+//	{"name":"value","array":[null,false,true,3.14159],"object":{"k":"v"}}
+//
+// can be composed with the following calls (ignoring errors for brevity):
+//
+//	e.WriteToken(ObjectStart)        // {
+//	e.WriteToken(String("name"))     // "name"
+//	e.WriteToken(String("value"))    // "value"
+//	e.WriteValue(Value(`"array"`))   // "array"
+//	e.WriteToken(ArrayStart)         // [
+//	e.WriteToken(Null)               // null
+//	e.WriteToken(False)              // false
+//	e.WriteValue(Value("true"))      // true
+//	e.WriteToken(Float(3.14159))     // 3.14159
+//	e.WriteToken(ArrayEnd)           // ]
+//	e.WriteValue(Value(`"object"`))  // "object"
+//	e.WriteValue(Value(`{"k":"v"}`)) // {"k":"v"}
+//	e.WriteToken(ObjectEnd)          // }
+//
+// The above is one of many possible sequence of calls and
+// may not represent the most sensible method to call for any given token/value.
+// For example, it is probably more common to call [Encoder.WriteToken] with a string
+// for object names.
+type Encoder struct {
+	s encoderState
+}
+
+// encoderState is the low-level state of Encoder.
+// It has exported fields and method for use by the "json" package.
+type encoderState struct {
+	state
+	encodeBuffer
+	jsonopts.Struct
+
+	SeenPointers map[any]struct{} // only used when marshaling; identical to json.seenPointers
+}
+
+// encodeBuffer is a buffer split into 2 segments:
+//
+//   - buf[0:len(buf)]        // written (but unflushed) portion of the buffer
+//   - buf[len(buf):cap(buf)] // unused portion of the buffer
+type encodeBuffer struct {
+	Buf []byte // may alias wr if it is a bytes.Buffer
+
+	// baseOffset is added to len(buf) to obtain the absolute offset
+	// relative to the start of io.Writer stream.
+	baseOffset int64
+
+	wr io.Writer
+
+	// maxValue is the approximate maximum Value size passed to WriteValue.
+	maxValue int
+	// unusedCache is the buffer returned by the UnusedBuffer method.
+	unusedCache []byte
+	// bufStats is statistics about buffer utilization.
+	// It is only used with pooled encoders in pools.go.
+	bufStats bufferStatistics
+}
+
+// NewEncoder constructs a new streaming encoder writing to w
+// configured with the provided options.
+// It flushes the internal buffer when the buffer is sufficiently full or
+// when a top-level value has been written.
+//
+// If w is a [bytes.Buffer], then the encoder appends directly into the buffer
+// without copying the contents from an intermediate buffer.
+func NewEncoder(w io.Writer, opts ...Options) *Encoder {
+	e := new(Encoder)
+	e.Reset(w, opts...)
+	return e
+}
+
+// Reset resets an encoder such that it is writing afresh to w and
+// configured with the provided options. Reset must not be called on
+// a Encoder passed to the [encoding/json/v2.MarshalerV2.MarshalJSONV2] method
+// or the [encoding/json/v2.MarshalFuncV2] function.
+func (e *Encoder) Reset(w io.Writer, opts ...Options) {
+	switch {
+	case e == nil:
+		panic("jsontext: invalid nil Encoder")
+	case w == nil:
+		panic("jsontext: invalid nil io.Writer")
+	case e.s.Flags.Get(jsonflags.WithinArshalCall):
+		panic("jsontext: cannot reset Encoder passed to json.MarshalerV2")
+	}
+	e.s.reset(nil, w, opts...)
+}
+
+func (e *encoderState) reset(b []byte, w io.Writer, opts ...Options) {
+	e.state.reset()
+	e.encodeBuffer = encodeBuffer{Buf: b, wr: w, bufStats: e.bufStats}
+	if bb, ok := w.(*bytes.Buffer); ok && bb != nil {
+		e.Buf = bb.Bytes()[bb.Len():] // alias the unused buffer of bb
+	}
+	e.Struct = jsonopts.Struct{}
+	e.Struct.Join(opts...)
+	if e.Flags.Get(jsonflags.Expand) && !e.Flags.Has(jsonflags.Indent) {
+		e.Indent = "\t"
+	}
+}
+
+// NeedFlush determines whether to flush at this point.
+func (e *encoderState) NeedFlush() bool {
+	// NOTE: This function is carefully written to be inlinable.
+
+	// Avoid flushing if e.wr is nil since there is no underlying writer.
+	// Flush if less than 25% of the capacity remains.
+	// Flushing at some constant fraction ensures that the buffer stops growing
+	// so long as the largest Token or Value fits within that unused capacity.
+	return e.wr != nil && (e.Tokens.Depth() == 1 || len(e.Buf) > 3*cap(e.Buf)/4)
+}
+
+// Flush flushes the buffer to the underlying io.Writer.
+// It may append a trailing newline after the top-level value.
+func (e *encoderState) Flush() error {
+	if e.wr == nil || e.avoidFlush() {
+		return nil
+	}
+
+	// In streaming mode, always emit a newline after the top-level value.
+	if e.Tokens.Depth() == 1 && !e.Flags.Get(jsonflags.OmitTopLevelNewline) {
+		e.Buf = append(e.Buf, '\n')
+	}
+
+	// Inform objectNameStack that we are about to flush the buffer content.
+	e.Names.copyQuotedBuffer(e.Buf)
+
+	// Specialize bytes.Buffer for better performance.
+	if bb, ok := e.wr.(*bytes.Buffer); ok {
+		// If e.buf already aliases the internal buffer of bb,
+		// then the Write call simply increments the internal offset,
+		// otherwise Write operates as expected.
+		// See https://go.dev/issue/42986.
+		n, _ := bb.Write(e.Buf) // never fails unless bb is nil
+		e.baseOffset += int64(n)
+
+		// If the internal buffer of bytes.Buffer is too small,
+		// append operations elsewhere in the Encoder may grow the buffer.
+		// This would be semantically correct, but hurts performance.
+		// As such, ensure 25% of the current length is always available
+		// to reduce the probability that other appends must allocate.
+		if avail := bb.Available(); avail < bb.Len()/4 {
+			bb.Grow(avail + 1)
+		}
+
+		e.Buf = bb.AvailableBuffer()
+		return nil
+	}
+
+	// Flush the internal buffer to the underlying io.Writer.
+	n, err := e.wr.Write(e.Buf)
+	e.baseOffset += int64(n)
+	if err != nil {
+		// In the event of an error, preserve the unflushed portion.
+		// Thus, write errors aren't fatal so long as the io.Writer
+		// maintains consistent state after errors.
+		if n > 0 {
+			e.Buf = e.Buf[:copy(e.Buf, e.Buf[n:])]
+		}
+		return &ioError{action: "write", err: err}
+	}
+	e.Buf = e.Buf[:0]
+
+	// Check whether to grow the buffer.
+	// Note that cap(e.buf) may already exceed maxBufferSize since
+	// an append elsewhere already grew it to store a large token.
+	const maxBufferSize = 4 << 10
+	const growthSizeFactor = 2 // higher value is faster
+	const growthRateFactor = 2 // higher value is slower
+	// By default, grow if below the maximum buffer size.
+	grow := cap(e.Buf) <= maxBufferSize/growthSizeFactor
+	// Growing can be expensive, so only grow
+	// if a sufficient number of bytes have been processed.
+	grow = grow && int64(cap(e.Buf)) < e.previousOffsetEnd()/growthRateFactor
+	if grow {
+		e.Buf = make([]byte, 0, cap(e.Buf)*growthSizeFactor)
+	}
+
+	return nil
+}
+
+// injectSyntacticErrorWithPosition wraps a SyntacticError with the position,
+// otherwise it returns the error as is.
+// It takes a position relative to the start of the start of e.buf.
+func (e *encodeBuffer) injectSyntacticErrorWithPosition(err error, pos int) error {
+	if serr, ok := err.(*SyntacticError); ok {
+		return serr.withOffset(e.baseOffset + int64(pos))
+	}
+	return err
+}
+
+func (e *encodeBuffer) previousOffsetEnd() int64 { return e.baseOffset + int64(len(e.Buf)) }
+func (e *encodeBuffer) unflushedBuffer() []byte  { return e.Buf }
+
+// avoidFlush indicates whether to avoid flushing to ensure there is always
+// enough in the buffer to unwrite the last object member if it were empty.
+func (e *encoderState) avoidFlush() bool {
+	switch {
+	case e.Tokens.Last.Length() == 0:
+		// Never flush after ObjectStart or ArrayStart since we don't know yet
+		// if the object or array will end up being empty.
+		return true
+	case e.Tokens.Last.needObjectValue():
+		// Never flush before the object value since we don't know yet
+		// if the object value will end up being empty.
+		return true
+	case e.Tokens.Last.NeedObjectName() && len(e.Buf) >= 2:
+		// Never flush after the object value if it does turn out to be empty.
+		switch string(e.Buf[len(e.Buf)-2:]) {
+		case `ll`, `""`, `{}`, `[]`: // last two bytes of every empty value
+			return true
+		}
+	}
+	return false
+}
+
+// UnwriteEmptyObjectMember unwrites the last object member if it is empty
+// and reports whether it performed an unwrite operation.
+func (e *encoderState) UnwriteEmptyObjectMember(prevName *string) bool {
+	if last := e.Tokens.Last; !last.isObject() || !last.NeedObjectName() || last.Length() == 0 {
+		panic("BUG: must be called on an object after writing a value")
+	}
+
+	// The flushing logic is modified to never flush a trailing empty value.
+	// The encoder never writes trailing whitespace eagerly.
+	b := e.unflushedBuffer()
+
+	// Detect whether the last value was empty.
+	var n int
+	if len(b) >= 3 {
+		switch string(b[len(b)-2:]) {
+		case "ll": // last two bytes of `null`
+			n = len(`null`)
+		case `""`:
+			// It is possible for a non-empty string to have `""` as a suffix
+			// if the second to the last quote was escaped.
+			if b[len(b)-3] == '\\' {
+				return false // e.g., `"\""` is not empty
+			}
+			n = len(`""`)
+		case `{}`:
+			n = len(`{}`)
+		case `[]`:
+			n = len(`[]`)
+		}
+	}
+	if n == 0 {
+		return false
+	}
+
+	// Unwrite the value, whitespace, colon, name, whitespace, and comma.
+	b = b[:len(b)-n]
+	b = jsonwire.TrimSuffixWhitespace(b)
+	b = jsonwire.TrimSuffixByte(b, ':')
+	b = jsonwire.TrimSuffixString(b)
+	b = jsonwire.TrimSuffixWhitespace(b)
+	b = jsonwire.TrimSuffixByte(b, ',')
+	e.Buf = b // store back truncated unflushed buffer
+
+	// Undo state changes.
+	e.Tokens.Last.decrement() // for object member value
+	e.Tokens.Last.decrement() // for object member name
+	if !e.Flags.Get(jsonflags.AllowDuplicateNames) {
+		if e.Tokens.Last.isActiveNamespace() {
+			e.Namespaces.Last().removeLast()
+		}
+		e.Names.clearLast()
+		if prevName != nil {
+			e.Names.copyQuotedBuffer(e.Buf) // required by objectNameStack.replaceLastUnquotedName
+			e.Names.replaceLastUnquotedName(*prevName)
+		}
+	}
+	return true
+}
+
+// UnwriteOnlyObjectMemberName unwrites the only object member name
+// and returns the unquoted name.
+func (e *encoderState) UnwriteOnlyObjectMemberName() string {
+	if last := e.Tokens.Last; !last.isObject() || last.Length() != 1 {
+		panic("BUG: must be called on an object after writing first name")
+	}
+
+	// Unwrite the name and whitespace.
+	b := jsonwire.TrimSuffixString(e.Buf)
+	isVerbatim := bytes.IndexByte(e.Buf[len(b):], '\\') < 0
+	name := string(jsonwire.UnquoteMayCopy(e.Buf[len(b):], isVerbatim))
+	e.Buf = jsonwire.TrimSuffixWhitespace(b)
+
+	// Undo state changes.
+	e.Tokens.Last.decrement()
+	if !e.Flags.Get(jsonflags.AllowDuplicateNames) {
+		if e.Tokens.Last.isActiveNamespace() {
+			e.Namespaces.Last().removeLast()
+		}
+		e.Names.clearLast()
+	}
+	return name
+}
+
+// WriteToken writes the next token and advances the internal write offset.
+//
+// The provided token kind must be consistent with the JSON grammar.
+// For example, it is an error to provide a number when the encoder
+// is expecting an object name (which is always a string), or
+// to provide an end object delimiter when the encoder is finishing an array.
+// If the provided token is invalid, then it reports a [SyntacticError] and
+// the internal state remains unchanged. The offset reported
+// in [SyntacticError] will be relative to the [Encoder.OutputOffset].
+func (e *Encoder) WriteToken(t Token) error {
+	return e.s.WriteToken(t)
+}
+func (e *encoderState) WriteToken(t Token) error {
+	k := t.Kind()
+	b := e.Buf // use local variable to avoid mutating e in case of error
+
+	// Append any delimiters or optional whitespace.
+	b = e.Tokens.MayAppendDelim(b, k)
+	if e.Flags.Get(jsonflags.Expand) {
+		b = e.appendWhitespace(b, k)
+	}
+	pos := len(b) // offset before the token
+
+	// Append the token to the output and to the state machine.
+	var err error
+	switch k {
+	case 'n':
+		b = append(b, "null"...)
+		err = e.Tokens.appendLiteral()
+	case 'f':
+		b = append(b, "false"...)
+		err = e.Tokens.appendLiteral()
+	case 't':
+		b = append(b, "true"...)
+		err = e.Tokens.appendLiteral()
+	case '"':
+		if b, err = t.appendString(b, &e.Flags); err != nil {
+			break
+		}
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) && e.Tokens.Last.NeedObjectName() {
+			if !e.Tokens.Last.isValidNamespace() {
+				err = errInvalidNamespace
+				break
+			}
+			if e.Tokens.Last.isActiveNamespace() && !e.Namespaces.Last().insertQuoted(b[pos:], false) {
+				err = newDuplicateNameError(b[pos:])
+				break
+			}
+			e.Names.ReplaceLastQuotedOffset(pos) // only replace if insertQuoted succeeds
+		}
+		err = e.Tokens.appendString()
+	case '0':
+		if b, err = t.appendNumber(b, e.Flags.Get(jsonflags.CanonicalizeNumbers)); err != nil {
+			break
+		}
+		err = e.Tokens.appendNumber()
+	case '{':
+		b = append(b, '{')
+		if err = e.Tokens.pushObject(); err != nil {
+			break
+		}
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) {
+			e.Names.push()
+			e.Namespaces.push()
+		}
+	case '}':
+		b = append(b, '}')
+		if err = e.Tokens.popObject(); err != nil {
+			break
+		}
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) {
+			e.Names.pop()
+			e.Namespaces.pop()
+		}
+	case '[':
+		b = append(b, '[')
+		err = e.Tokens.pushArray()
+	case ']':
+		b = append(b, ']')
+		err = e.Tokens.popArray()
+	default:
+		err = &SyntacticError{str: "invalid json.Token"}
+	}
+	if err != nil {
+		return e.injectSyntacticErrorWithPosition(err, pos)
+	}
+
+	// Finish off the buffer and store it back into e.
+	e.Buf = b
+	if e.NeedFlush() {
+		return e.Flush()
+	}
+	return nil
+}
+
+// AppendRaw appends either a raw string (without double quotes) or number.
+// Specify safeASCII if the string output is guaranteed to be ASCII
+// without any characters (including '<', '>', and '&') that need escaping,
+// otherwise this will validate whether the string needs escaping.
+// The appended bytes for a JSON number must be valid.
+//
+// This is a specialized implementation of Encoder.WriteValue
+// that allows appending directly into the buffer.
+// It is only called from marshal logic in the "json" package.
+func (e *encoderState) AppendRaw(k Kind, safeASCII bool, appendFn func([]byte) ([]byte, error)) error {
+	b := e.Buf // use local variable to avoid mutating e in case of error
+
+	// Append any delimiters or optional whitespace.
+	b = e.Tokens.MayAppendDelim(b, k)
+	if e.Flags.Get(jsonflags.Expand) {
+		b = e.appendWhitespace(b, k)
+	}
+	pos := len(b) // offset before the token
+
+	var err error
+	switch k {
+	case '"':
+		// Append directly into the encoder buffer by assuming that
+		// most of the time none of the characters need escaping.
+		b = append(b, '"')
+		if b, err = appendFn(b); err != nil {
+			return err
+		}
+		b = append(b, '"')
+
+		// Check whether we need to escape the string and if necessary
+		// copy it to a scratch buffer and then escape it back.
+		isVerbatim := safeASCII || !jsonwire.NeedEscape(b[pos+len(`"`):len(b)-len(`"`)])
+		if !isVerbatim {
+			var err error
+			b2 := append(e.unusedCache, b[pos+len(`"`):len(b)-len(`"`)]...)
+			b, err = jsonwire.AppendQuote(b[:pos], string(b2), &e.Flags)
+			e.unusedCache = b2[:0]
+			if err != nil {
+				return e.injectSyntacticErrorWithPosition(err, pos)
+			}
+		}
+
+		// Update the state machine.
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) && e.Tokens.Last.NeedObjectName() {
+			if !e.Tokens.Last.isValidNamespace() {
+				return errInvalidNamespace
+			}
+			if e.Tokens.Last.isActiveNamespace() && !e.Namespaces.Last().insertQuoted(b[pos:], isVerbatim) {
+				err := newDuplicateNameError(b[pos:])
+				return e.injectSyntacticErrorWithPosition(err, pos)
+			}
+			e.Names.ReplaceLastQuotedOffset(pos) // only replace if insertQuoted succeeds
+		}
+		if err := e.Tokens.appendString(); err != nil {
+			return e.injectSyntacticErrorWithPosition(err, pos)
+		}
+	case '0':
+		if b, err = appendFn(b); err != nil {
+			return err
+		}
+		if err := e.Tokens.appendNumber(); err != nil {
+			return e.injectSyntacticErrorWithPosition(err, pos)
+		}
+	default:
+		panic("BUG: invalid kind")
+	}
+
+	// Finish off the buffer and store it back into e.
+	e.Buf = b
+	if e.NeedFlush() {
+		return e.Flush()
+	}
+	return nil
+}
+
+// WriteValue writes the next raw value and advances the internal write offset.
+// The Encoder does not simply copy the provided value verbatim, but
+// parses it to ensure that it is syntactically valid and reformats it
+// according to how the Encoder is configured to format whitespace and strings.
+// If [AllowInvalidUTF8] is specified, then any invalid UTF-8 is mangled
+// as the Unicode replacement character, U+FFFD.
+//
+// The provided value kind must be consistent with the JSON grammar
+// (see examples on [Encoder.WriteToken]). If the provided value is invalid,
+// then it reports a [SyntacticError] and the internal state remains unchanged.
+// The offset reported in [SyntacticError] will be relative to the
+// [Encoder.OutputOffset] plus the offset into v of any encountered syntax error.
+func (e *Encoder) WriteValue(v Value) error {
+	return e.s.WriteValue(v)
+}
+func (e *encoderState) WriteValue(v Value) error {
+	e.maxValue |= len(v) // bitwise OR is a fast approximation of max
+
+	k := v.Kind()
+	b := e.Buf // use local variable to avoid mutating e in case of error
+
+	// Append any delimiters or optional whitespace.
+	b = e.Tokens.MayAppendDelim(b, k)
+	if e.Flags.Get(jsonflags.Expand) {
+		b = e.appendWhitespace(b, k)
+	}
+	pos := len(b) // offset before the value
+
+	// Append the value the output.
+	var n int
+	n += jsonwire.ConsumeWhitespace(v[n:])
+	b, m, err := e.reformatValue(b, v[n:], e.Tokens.Depth())
+	if err != nil {
+		return e.injectSyntacticErrorWithPosition(err, pos+n+m)
+	}
+	n += m
+	n += jsonwire.ConsumeWhitespace(v[n:])
+	if len(v) > n {
+		err = newInvalidCharacterError(v[n:], "after top-level value")
+		return e.injectSyntacticErrorWithPosition(err, pos+n)
+	}
+
+	// Append the kind to the state machine.
+	switch k {
+	case 'n', 'f', 't':
+		err = e.Tokens.appendLiteral()
+	case '"':
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) && e.Tokens.Last.NeedObjectName() {
+			if !e.Tokens.Last.isValidNamespace() {
+				err = errInvalidNamespace
+				break
+			}
+			if e.Tokens.Last.isActiveNamespace() && !e.Namespaces.Last().insertQuoted(b[pos:], false) {
+				err = newDuplicateNameError(b[pos:])
+				break
+			}
+			e.Names.ReplaceLastQuotedOffset(pos) // only replace if insertQuoted succeeds
+		}
+		err = e.Tokens.appendString()
+	case '0':
+		err = e.Tokens.appendNumber()
+	case '{':
+		if err = e.Tokens.pushObject(); err != nil {
+			break
+		}
+		if err = e.Tokens.popObject(); err != nil {
+			panic("BUG: popObject should never fail immediately after pushObject: " + err.Error())
+		}
+	case '[':
+		if err = e.Tokens.pushArray(); err != nil {
+			break
+		}
+		if err = e.Tokens.popArray(); err != nil {
+			panic("BUG: popArray should never fail immediately after pushArray: " + err.Error())
+		}
+	}
+	if err != nil {
+		return e.injectSyntacticErrorWithPosition(err, pos)
+	}
+
+	// Finish off the buffer and store it back into e.
+	e.Buf = b
+	if e.NeedFlush() {
+		return e.Flush()
+	}
+	return nil
+}
+
+// appendWhitespace appends whitespace that immediately precedes the next token.
+func (e *encoderState) appendWhitespace(b []byte, next Kind) []byte {
+	if e.Tokens.needDelim(next) == ':' {
+		return append(b, ' ')
+	} else {
+		return e.AppendIndent(b, e.Tokens.NeedIndent(next))
+	}
+}
+
+// AppendIndent appends the appropriate number of indentation characters
+// for the current nested level, n.
+func (e *encoderState) AppendIndent(b []byte, n int) []byte {
+	if n == 0 {
+		return b
+	}
+	b = append(b, '\n')
+	b = append(b, e.IndentPrefix...)
+	for ; n > 1; n-- {
+		b = append(b, e.Indent...)
+	}
+	return b
+}
+
+// reformatValue parses a JSON value from the start of src and
+// appends it to the end of dst, reformatting whitespace and strings as needed.
+// It returns the extended dst buffer and the number of consumed input bytes.
+func (e *encoderState) reformatValue(dst []byte, src Value, depth int) ([]byte, int, error) {
+	// TODO: Should this update ValueFlags as input?
+	if len(src) == 0 {
+		return dst, 0, io.ErrUnexpectedEOF
+	}
+	switch k := Kind(src[0]).normalize(); k {
+	case 'n':
+		if jsonwire.ConsumeNull(src) == 0 {
+			n, err := jsonwire.ConsumeLiteral(src, "null")
+			return dst, n, err
+		}
+		return append(dst, "null"...), len("null"), nil
+	case 'f':
+		if jsonwire.ConsumeFalse(src) == 0 {
+			n, err := jsonwire.ConsumeLiteral(src, "false")
+			return dst, n, err
+		}
+		return append(dst, "false"...), len("false"), nil
+	case 't':
+		if jsonwire.ConsumeTrue(src) == 0 {
+			n, err := jsonwire.ConsumeLiteral(src, "true")
+			return dst, n, err
+		}
+		return append(dst, "true"...), len("true"), nil
+	case '"':
+		if n := jsonwire.ConsumeSimpleString(src); n > 0 {
+			dst, src = append(dst, src[:n]...), src[n:] // copy simple strings verbatim
+			return dst, n, nil
+		}
+		return jsonwire.ReformatString(dst, src, &e.Flags)
+	case '0':
+		if n := jsonwire.ConsumeSimpleNumber(src); n > 0 && !e.Flags.Get(jsonflags.CanonicalizeNumbers) {
+			dst, src = append(dst, src[:n]...), src[n:] // copy simple numbers verbatim
+			return dst, n, nil
+		}
+		return jsonwire.ReformatNumber(dst, src, e.Flags.Get(jsonflags.CanonicalizeNumbers))
+	case '{':
+		return e.reformatObject(dst, src, depth)
+	case '[':
+		return e.reformatArray(dst, src, depth)
+	default:
+		return dst, 0, newInvalidCharacterError(src, "at start of value")
+	}
+}
+
+// reformatObject parses a JSON object from the start of src and
+// appends it to the end of src, reformatting whitespace and strings as needed.
+// It returns the extended dst buffer and the number of consumed input bytes.
+func (e *encoderState) reformatObject(dst []byte, src Value, depth int) ([]byte, int, error) {
+	// Append object start.
+	if len(src) == 0 || src[0] != '{' {
+		panic("BUG: reformatObject must be called with a buffer that starts with '{'")
+	} else if depth == maxNestingDepth+1 {
+		return dst, 0, errMaxDepth
+	}
+	dst = append(dst, '{')
+	n := len("{")
+
+	// Append (possible) object end.
+	n += jsonwire.ConsumeWhitespace(src[n:])
+	if uint(len(src)) <= uint(n) {
+		return dst, n, io.ErrUnexpectedEOF
+	}
+	if src[n] == '}' {
+		dst = append(dst, '}')
+		n += len("}")
+		return dst, n, nil
+	}
+
+	var err error
+	var names *objectNamespace
+	if !e.Flags.Get(jsonflags.AllowDuplicateNames) {
+		e.Namespaces.push()
+		defer e.Namespaces.pop()
+		names = e.Namespaces.Last()
+	}
+	depth++
+	for {
+		// Append optional newline and indentation.
+		if e.Flags.Get(jsonflags.Expand) {
+			dst = e.AppendIndent(dst, depth)
+		}
+
+		// Append object name.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		m := jsonwire.ConsumeSimpleString(src[n:])
+		if m > 0 {
+			dst = append(dst, src[n:n+m]...)
+		} else {
+			dst, m, err = jsonwire.ReformatString(dst, src[n:], &e.Flags)
+			if err != nil {
+				return dst, n + m, err
+			}
+		}
+		// TODO: Specify whether the name is verbatim or not.
+		if !e.Flags.Get(jsonflags.AllowDuplicateNames) && !names.insertQuoted(src[n:n+m], false) {
+			return dst, n, newDuplicateNameError(src[n : n+m])
+		}
+		n += m
+
+		// Append colon.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		if src[n] != ':' {
+			return dst, n, newInvalidCharacterError(src[n:], "after object name (expecting ':')")
+		}
+		dst = append(dst, ':')
+		n += len(":")
+		if e.Flags.Get(jsonflags.Expand) {
+			dst = append(dst, ' ')
+		}
+
+		// Append object value.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		dst, m, err = e.reformatValue(dst, src[n:], depth)
+		if err != nil {
+			return dst, n + m, err
+		}
+		n += m
+
+		// Append comma or object end.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		switch src[n] {
+		case ',':
+			dst = append(dst, ',')
+			n += len(",")
+			continue
+		case '}':
+			if e.Flags.Get(jsonflags.Expand) {
+				dst = e.AppendIndent(dst, depth-1)
+			}
+			dst = append(dst, '}')
+			n += len("}")
+			return dst, n, nil
+		default:
+			return dst, n, newInvalidCharacterError(src[n:], "after object value (expecting ',' or '}')")
+		}
+	}
+}
+
+// reformatArray parses a JSON array from the start of src and
+// appends it to the end of dst, reformatting whitespace and strings as needed.
+// It returns the extended dst buffer and the number of consumed input bytes.
+func (e *encoderState) reformatArray(dst []byte, src Value, depth int) ([]byte, int, error) {
+	// Append array start.
+	if len(src) == 0 || src[0] != '[' {
+		panic("BUG: reformatArray must be called with a buffer that starts with '['")
+	} else if depth == maxNestingDepth+1 {
+		return dst, 0, errMaxDepth
+	}
+	dst = append(dst, '[')
+	n := len("[")
+
+	// Append (possible) array end.
+	n += jsonwire.ConsumeWhitespace(src[n:])
+	if uint(len(src)) <= uint(n) {
+		return dst, n, io.ErrUnexpectedEOF
+	}
+	if src[n] == ']' {
+		dst = append(dst, ']')
+		n += len("]")
+		return dst, n, nil
+	}
+
+	var err error
+	depth++
+	for {
+		// Append optional newline and indentation.
+		if e.Flags.Get(jsonflags.Expand) {
+			dst = e.AppendIndent(dst, depth)
+		}
+
+		// Append array value.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		var m int
+		dst, m, err = e.reformatValue(dst, src[n:], depth)
+		if err != nil {
+			return dst, n + m, err
+		}
+		n += m
+
+		// Append comma or array end.
+		n += jsonwire.ConsumeWhitespace(src[n:])
+		if uint(len(src)) <= uint(n) {
+			return dst, n, io.ErrUnexpectedEOF
+		}
+		switch src[n] {
+		case ',':
+			dst = append(dst, ',')
+			n += len(",")
+			continue
+		case ']':
+			if e.Flags.Get(jsonflags.Expand) {
+				dst = e.AppendIndent(dst, depth-1)
+			}
+			dst = append(dst, ']')
+			n += len("]")
+			return dst, n, nil
+		default:
+			return dst, n, newInvalidCharacterError(src[n:], "after array value (expecting ',' or ']')")
+		}
+	}
+}
+
+// OutputOffset returns the current output byte offset. It gives the location
+// of the next byte immediately after the most recently written token or value.
+// The number of bytes actually written to the underlying [io.Writer] may be less
+// than this offset due to internal buffering effects.
+func (e *Encoder) OutputOffset() int64 {
+	return e.s.previousOffsetEnd()
+}
+
+// UnusedBuffer returns a zero-length buffer with a possible non-zero capacity.
+// This buffer is intended to be used to populate a [Value]
+// being passed to an immediately succeeding [Encoder.WriteValue] call.
+//
+// Example usage:
+//
+//	b := d.UnusedBuffer()
+//	b = append(b, '"')
+//	b = appendString(b, v) // append the string formatting of v
+//	b = append(b, '"')
+//	... := d.WriteValue(b)
+//
+// It is the user's responsibility to ensure that the value is valid JSON.
+func (e *Encoder) UnusedBuffer() []byte {
+	// NOTE: We don't return e.buf[len(e.buf):cap(e.buf)] since WriteValue would
+	// need to take special care to avoid mangling the data while reformatting.
+	// WriteValue can't easily identify whether the input Value aliases e.buf
+	// without using unsafe.Pointer. Thus, we just return a different buffer.
+	// Should this ever alias e.buf, we need to consider how it operates with
+	// the specialized performance optimization for bytes.Buffer.
+	n := 1 << bits.Len(uint(e.s.maxValue|63)) // fast approximation for max length
+	if cap(e.s.unusedCache) < n {
+		e.s.unusedCache = make([]byte, 0, n)
+	}
+	return e.s.unusedCache
+}
+
+// StackDepth returns the depth of the state machine for written JSON data.
+// Each level on the stack represents a nested JSON object or array.
+// It is incremented whenever an [ObjectStart] or [ArrayStart] token is encountered
+// and decremented whenever an [ObjectEnd] or [ArrayEnd] token is encountered.
+// The depth is zero-indexed, where zero represents the top-level JSON value.
+func (e *Encoder) StackDepth() int {
+	// NOTE: Keep in sync with Decoder.StackDepth.
+	return e.s.Tokens.Depth() - 1
+}
+
+// StackIndex returns information about the specified stack level.
+// It must be a number between 0 and [Encoder.StackDepth], inclusive.
+// For each level, it reports the kind:
+//
+//   - 0 for a level of zero,
+//   - '{' for a level representing a JSON object, and
+//   - '[' for a level representing a JSON array.
+//
+// It also reports the length of that JSON object or array.
+// Each name and value in a JSON object is counted separately,
+// so the effective number of members would be half the length.
+// A complete JSON object must have an even length.
+func (e *Encoder) StackIndex(i int) (Kind, int) {
+	// NOTE: Keep in sync with Decoder.StackIndex.
+	switch s := e.s.Tokens.index(i); {
+	case i > 0 && s.isObject():
+		return '{', s.Length()
+	case i > 0 && s.isArray():
+		return '[', s.Length()
+	default:
+		return 0, s.Length()
+	}
+}
+
+// StackPointer returns a JSON Pointer (RFC 6901) to the most recently written value.
+// Object names are only present if [AllowDuplicateNames] is false, otherwise
+// object members are represented using their index within the object.
+func (e *Encoder) StackPointer() string {
+	e.s.Names.copyQuotedBuffer(e.s.Buf)
+	return string(e.s.appendStackPointer(nil))
+}

vendor/github.com/go-json-experiment/json/jsontext/errors.go

@@ -0,0 +1,60 @@
+// 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 jsontext
+
+import (
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+const errorPrefix = "jsontext: "
+
+type ioError struct {
+	action string // either "read" or "write"
+	err    error
+}
+
+func (e *ioError) Error() string {
+	return errorPrefix + e.action + " error: " + e.err.Error()
+}
+func (e *ioError) Unwrap() error {
+	return e.err
+}
+
+// SyntacticError is a description of a syntactic error that occurred when
+// encoding or decoding JSON according to the grammar.
+//
+// The contents of this error as produced by this package may change over time.
+type SyntacticError struct {
+	requireKeyedLiterals
+	nonComparable
+
+	// ByteOffset indicates that an error occurred after this byte offset.
+	ByteOffset int64
+	str        string
+}
+
+func (e *SyntacticError) Error() string {
+	return errorPrefix + e.str
+}
+func (e *SyntacticError) withOffset(pos int64) error {
+	return &SyntacticError{ByteOffset: pos, str: e.str}
+}
+
+func newDuplicateNameError[Bytes ~[]byte | ~string](quoted Bytes) *SyntacticError {
+	return &SyntacticError{str: "duplicate name " + string(quoted) + " in object"}
+}
+
+func newInvalidCharacterError[Bytes ~[]byte | ~string](prefix Bytes, where string) *SyntacticError {
+	what := jsonwire.QuoteRune(prefix)
+	return &SyntacticError{str: "invalid character " + what + " " + where}
+}
+
+// TODO: Error types between "json", "jsontext", and "jsonwire" is a mess.
+// Clean this up.
+func init() {
+	// Inject behavior in "jsonwire" so that it can produce SyntacticError types.
+	jsonwire.NewError = func(s string) error { return &SyntacticError{str: s} }
+	jsonwire.ErrInvalidUTF8 = &SyntacticError{str: jsonwire.ErrInvalidUTF8.Error()}
+}

vendor/github.com/go-json-experiment/json/jsontext/export.go

@@ -0,0 +1,83 @@
+// 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.
+
+package jsontext
+
+import (
+	"io"
+
+	"github.com/go-json-experiment/json/internal"
+)
+
+// Internal is for internal use only.
+// This is exempt from the Go compatibility agreement.
+var Internal exporter
+
+type exporter struct{}
+
+// Export exposes internal functionality from "jsontext" to "json".
+// This cannot be dynamically called by other packages since
+// they cannot obtain a reference to the internal.AllowInternalUse value.
+func (exporter) Export(p *internal.NotForPublicUse) export {
+	if p != &internal.AllowInternalUse {
+		panic("unauthorized call to Export")
+	}
+	return export{}
+}
+
+// The export type exposes functionality to packages with visibility to
+// the internal.AllowInternalUse variable. The "json" package uses this
+// to modify low-level state in the Encoder and Decoder types.
+// It mutates the state directly instead of calling ReadToken or WriteToken
+// since this is more performant. The public APIs need to track state to ensure
+// that users are constructing a valid JSON value, but the "json" implementation
+// guarantees that it emits valid JSON by the structure of the code itself.
+type export struct{}
+
+// Encoder returns a pointer to the underlying encoderState.
+func (export) Encoder(e *Encoder) *encoderState { return &e.s }
+
+// Decoder returns a pointer to the underlying decoderState.
+func (export) Decoder(d *Decoder) *decoderState { return &d.s }
+
+func (export) GetBufferedEncoder(o ...Options) *Encoder {
+	return getBufferedEncoder(o...)
+}
+func (export) PutBufferedEncoder(e *Encoder) {
+	putBufferedEncoder(e)
+}
+
+func (export) GetStreamingEncoder(w io.Writer, o ...Options) *Encoder {
+	return getStreamingEncoder(w, o...)
+}
+func (export) PutStreamingEncoder(e *Encoder) {
+	putStreamingEncoder(e)
+}
+
+func (export) GetBufferedDecoder(b []byte, o ...Options) *Decoder {
+	return getBufferedDecoder(b, o...)
+}
+func (export) PutBufferedDecoder(d *Decoder) {
+	putBufferedDecoder(d)
+}
+
+func (export) GetStreamingDecoder(r io.Reader, o ...Options) *Decoder {
+	return getStreamingDecoder(r, o...)
+}
+func (export) PutStreamingDecoder(d *Decoder) {
+	putStreamingDecoder(d)
+}
+
+func (export) NewDuplicateNameError(quoted []byte, pos int64) error {
+	return newDuplicateNameError(quoted).withOffset(pos)
+}
+func (export) NewInvalidCharacterError(prefix, where string, pos int64) error {
+	return newInvalidCharacterError(prefix, where).withOffset(pos)
+}
+func (export) NewMissingNameError(pos int64) error {
+	return errMissingName.withOffset(pos)
+}
+func (export) NewInvalidUTF8Error(pos int64) error {
+	return errInvalidUTF8.withOffset(pos)
+}

vendor/github.com/go-json-experiment/json/jsontext/options.go

@@ -0,0 +1,178 @@
+// 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.
+
+package jsontext
+
+import (
+	"strings"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+// Options configures [NewEncoder], [Encoder.Reset], [NewDecoder],
+// and [Decoder.Reset] with specific features.
+// Each function takes in a variadic list of options, where properties
+// set in latter options override the value of previously set properties.
+//
+// The Options type is identical to [encoding/json.Options] and
+// [encoding/json/v2.Options]. Options from the other packages may
+// be passed to functionality in this package, but are ignored.
+// Options from this package may be used with the other packages.
+type Options = jsonopts.Options
+
+// AllowDuplicateNames specifies that JSON objects may contain
+// duplicate member names. Disabling the duplicate name check may provide
+// performance benefits, but breaks compliance with RFC 7493, section 2.3.
+// The input or output will still be compliant with RFC 8259,
+// which leaves the handling of duplicate names as unspecified behavior.
+//
+// This affects either encoding or decoding.
+func AllowDuplicateNames(v bool) Options {
+	if v {
+		return jsonflags.AllowDuplicateNames | 1
+	} else {
+		return jsonflags.AllowDuplicateNames | 0
+	}
+}
+
+// AllowInvalidUTF8 specifies that JSON strings may contain invalid UTF-8,
+// which will be mangled as the Unicode replacement character, U+FFFD.
+// This causes the encoder or decoder to break compliance with
+// RFC 7493, section 2.1, and RFC 8259, section 8.1.
+//
+// This affects either encoding or decoding.
+func AllowInvalidUTF8(v bool) Options {
+	if v {
+		return jsonflags.AllowInvalidUTF8 | 1
+	} else {
+		return jsonflags.AllowInvalidUTF8 | 0
+	}
+}
+
+// EscapeForHTML specifies that '<', '>', and '&' characters within JSON strings
+// should be escaped as a hexadecimal Unicode codepoint (e.g., \u003c) so that
+// the output is safe to embed within HTML.
+//
+// This only affects encoding and is ignored when decoding.
+func EscapeForHTML(v bool) Options {
+	if v {
+		return jsonflags.EscapeForHTML | 1
+	} else {
+		return jsonflags.EscapeForHTML | 0
+	}
+}
+
+// EscapeForJS specifies that U+2028 and U+2029 characters within JSON strings
+// should be escaped as a hexadecimal Unicode codepoint (e.g., \u2028) so that
+// the output is valid to embed within JavaScript. See RFC 8259, section 12.
+//
+// This only affects encoding and is ignored when decoding.
+func EscapeForJS(v bool) Options {
+	if v {
+		return jsonflags.EscapeForJS | 1
+	} else {
+		return jsonflags.EscapeForJS | 0
+	}
+}
+
+// Expand specifies that the JSON output should be expanded,
+// where every JSON object member or JSON array element
+// appears on a new, indented line according to the nesting depth.
+// If an indent is not already specified, then it defaults to using "\t".
+//
+// If set to false, then the output is compact,
+// where no whitespace is emitted between JSON values.
+//
+// This only affects encoding and is ignored when decoding.
+func Expand(v bool) Options {
+	if v {
+		return jsonflags.Expand | 1
+	} else {
+		return jsonflags.Expand | 0
+	}
+}
+
+// WithIndent specifies that the encoder should emit multiline output
+// where each element in a JSON object or array begins on a new, indented line
+// beginning with the indent prefix (see [WithIndentPrefix])
+// followed by one or more copies of indent according to the nesting depth.
+// The indent must only be composed of space or tab characters.
+//
+// If the intent to emit indented output without a preference for
+// the particular indent string, then use [Expand] instead.
+//
+// This only affects encoding and is ignored when decoding.
+// Use of this option implies [Expand] being set to true.
+func WithIndent(indent string) Options {
+	// Fast-path: Return a constant for common indents, which avoids allocating.
+	// These are derived from analyzing the Go module proxy on 2023-07-01.
+	switch indent {
+	case "\t":
+		return jsonopts.Indent("\t") // ~14k usages
+	case "    ":
+		return jsonopts.Indent("    ") // ~18k usages
+	case "   ":
+		return jsonopts.Indent("   ") // ~1.7k usages
+	case "  ":
+		return jsonopts.Indent("  ") // ~52k usages
+	case " ":
+		return jsonopts.Indent(" ") // ~12k usages
+	case "":
+		return jsonopts.Indent("") // ~1.5k usages
+	}
+
+	// Otherwise, allocate for this unique value.
+	if s := strings.Trim(indent, " \t"); len(s) > 0 {
+		panic("json: invalid character " + jsonwire.QuoteRune(s) + " in indent")
+	}
+	return jsonopts.Indent(indent)
+}
+
+// WithIndentPrefix specifies that the encoder should emit multiline output
+// where each element in a JSON object or array begins on a new, indented line
+// beginning with the indent prefix followed by one or more copies of indent
+// (see [WithIndent]) according to the nesting depth.
+// The prefix must only be composed of space or tab characters.
+//
+// This only affects encoding and is ignored when decoding.
+// Use of this option implies [Expand] being set to true.
+func WithIndentPrefix(prefix string) Options {
+	if s := strings.Trim(prefix, " \t"); len(s) > 0 {
+		panic("json: invalid character " + jsonwire.QuoteRune(s) + " in indent prefix")
+	}
+	return jsonopts.IndentPrefix(prefix)
+}
+
+/*
+// TODO(https://go.dev/issue/56733): Implement WithByteLimit and WithDepthLimit.
+
+// WithByteLimit sets a limit on the number of bytes of input or output bytes
+// that may be consumed or produced for each top-level JSON value.
+// If a [Decoder] or [Encoder] method call would need to consume/produce
+// more than a total of n bytes to make progress on the top-level JSON value,
+// then the call will report an error.
+// Whitespace before and within the top-level value are counted against the limit.
+// Whitespace after a top-level value are counted against the limit
+// for the next top-level value.
+//
+// A non-positive limit is equivalent to no limit at all.
+// If unspecified, the default limit is no limit at all.
+func WithByteLimit(n int64) Options {
+	return jsonopts.ByteLimit(max(n, 0))
+}
+
+// WithDepthLimit sets a limit on the maximum depth of JSON nesting
+// that may be consumed or produced for each top-level JSON value.
+// If a [Decoder] or [Encoder] method call would need to consume or produce
+// a depth greater than n to make progress on the top-level JSON value,
+// then the call will report an error.
+//
+// A non-positive limit is equivalent to no limit at all.
+// If unspecified, the default limit is 10000.
+func WithDepthLimit(n int) Options {
+	return jsonopts.DepthLimit(max(n, 0))
+}
+*/

vendor/github.com/go-json-experiment/json/jsontext/pools.go

@@ -0,0 +1,150 @@
+// 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 jsontext
+
+import (
+	"bytes"
+	"io"
+	"math/bits"
+	"sync"
+)
+
+// TODO(https://go.dev/issue/47657): Use sync.PoolOf.
+
+var (
+	// This owns the internal buffer since there is no io.Writer to output to.
+	// Since the buffer can get arbitrarily large in normal usage,
+	// there is statistical tracking logic to determine whether to recycle
+	// the internal buffer or not based on a history of utilization.
+	bufferedEncoderPool = &sync.Pool{New: func() any { return new(Encoder) }}
+
+	// This owns the internal buffer, but it is only used to temporarily store
+	// buffered JSON before flushing it to the underlying io.Writer.
+	// In a sufficiently efficient streaming mode, we do not expect the buffer
+	// to grow arbitrarily large. Thus, we avoid recycling large buffers.
+	streamingEncoderPool = &sync.Pool{New: func() any { return new(Encoder) }}
+
+	// This does not own the internal buffer since
+	// it is taken directly from the provided bytes.Buffer.
+	bytesBufferEncoderPool = &sync.Pool{New: func() any { return new(Encoder) }}
+)
+
+// bufferStatistics is statistics to track buffer utilization.
+// It is used to determine whether to recycle a buffer or not
+// to avoid https://go.dev/issue/23199.
+type bufferStatistics struct {
+	strikes int // number of times the buffer was under-utilized
+	prevLen int // length of previous buffer
+}
+
+func getBufferedEncoder(opts ...Options) *Encoder {
+	e := bufferedEncoderPool.Get().(*Encoder)
+	if e.s.Buf == nil {
+		// Round up to nearest 2ⁿ to make best use of malloc size classes.
+		// See runtime/sizeclasses.go on Go1.15.
+		// Logical OR with 63 to ensure 64 as the minimum buffer size.
+		n := 1 << bits.Len(uint(e.s.bufStats.prevLen|63))
+		e.s.Buf = make([]byte, 0, n)
+	}
+	e.s.reset(e.s.Buf[:0], nil, opts...)
+	return e
+}
+func putBufferedEncoder(e *Encoder) {
+	// Recycle large buffers only if sufficiently utilized.
+	// If a buffer is under-utilized enough times sequentially,
+	// then it is discarded, ensuring that a single large buffer
+	// won't be kept alive by a continuous stream of small usages.
+	//
+	// The worst case utilization is computed as:
+	//	MIN_UTILIZATION_THRESHOLD / (1 + MAX_NUM_STRIKES)
+	//
+	// For the constants chosen below, this is (25%)/(1+4) ⇒ 5%.
+	// This may seem low, but it ensures a lower bound on
+	// the absolute worst-case utilization. Without this check,
+	// this would be theoretically 0%, which is infinitely worse.
+	//
+	// See https://go.dev/issue/27735.
+	switch {
+	case cap(e.s.Buf) <= 4<<10: // always recycle buffers smaller than 4KiB
+		e.s.bufStats.strikes = 0
+	case cap(e.s.Buf)/4 <= len(e.s.Buf): // at least 25% utilization
+		e.s.bufStats.strikes = 0
+	case e.s.bufStats.strikes < 4: // at most 4 strikes
+		e.s.bufStats.strikes++
+	default: // discard the buffer; too large and too often under-utilized
+		e.s.bufStats.strikes = 0
+		e.s.bufStats.prevLen = len(e.s.Buf) // heuristic for size to allocate next time
+		e.s.Buf = nil
+	}
+	bufferedEncoderPool.Put(e)
+}
+
+func getStreamingEncoder(w io.Writer, opts ...Options) *Encoder {
+	if _, ok := w.(*bytes.Buffer); ok {
+		e := bytesBufferEncoderPool.Get().(*Encoder)
+		e.s.reset(nil, w, opts...) // buffer taken from bytes.Buffer
+		return e
+	} else {
+		e := streamingEncoderPool.Get().(*Encoder)
+		e.s.reset(e.s.Buf[:0], w, opts...) // preserve existing buffer
+		return e
+	}
+}
+func putStreamingEncoder(e *Encoder) {
+	if _, ok := e.s.wr.(*bytes.Buffer); ok {
+		bytesBufferEncoderPool.Put(e)
+	} else {
+		if cap(e.s.Buf) > 64<<10 {
+			e.s.Buf = nil // avoid pinning arbitrarily large amounts of memory
+		}
+		streamingEncoderPool.Put(e)
+	}
+}
+
+var (
+	// This does not own the internal buffer since it is externally provided.
+	bufferedDecoderPool = &sync.Pool{New: func() any { return new(Decoder) }}
+
+	// This owns the internal buffer, but it is only used to temporarily store
+	// buffered JSON fetched from the underlying io.Reader.
+	// In a sufficiently efficient streaming mode, we do not expect the buffer
+	// to grow arbitrarily large. Thus, we avoid recycling large buffers.
+	streamingDecoderPool = &sync.Pool{New: func() any { return new(Decoder) }}
+
+	// This does not own the internal buffer since
+	// it is taken directly from the provided bytes.Buffer.
+	bytesBufferDecoderPool = bufferedDecoderPool
+)
+
+func getBufferedDecoder(b []byte, opts ...Options) *Decoder {
+	d := bufferedDecoderPool.Get().(*Decoder)
+	d.s.reset(b, nil, opts...)
+	return d
+}
+func putBufferedDecoder(d *Decoder) {
+	bufferedDecoderPool.Put(d)
+}
+
+func getStreamingDecoder(r io.Reader, opts ...Options) *Decoder {
+	if _, ok := r.(*bytes.Buffer); ok {
+		d := bytesBufferDecoderPool.Get().(*Decoder)
+		d.s.reset(nil, r, opts...) // buffer taken from bytes.Buffer
+		return d
+	} else {
+		d := streamingDecoderPool.Get().(*Decoder)
+		d.s.reset(d.s.buf[:0], r, opts...) // preserve existing buffer
+		return d
+	}
+}
+func putStreamingDecoder(d *Decoder) {
+	if _, ok := d.s.rd.(*bytes.Buffer); ok {
+		bytesBufferDecoderPool.Put(d)
+	} else {
+		if cap(d.s.buf) > 64<<10 {
+			d.s.buf = nil // avoid pinning arbitrarily large amounts of memory
+		}
+		streamingDecoderPool.Put(d)
+	}
+}

vendor/github.com/go-json-experiment/json/jsontext/quote.go

@@ -0,0 +1,31 @@
+// 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.
+
+package jsontext
+
+import (
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+var errInvalidUTF8 = &SyntacticError{str: "invalid UTF-8 within string"}
+
+// AppendQuote appends a double-quoted JSON string literal representing src
+// to dst and returns the extended buffer.
+// It uses the minimal string representation per RFC 8785, section 3.2.2.2.
+// Invalid UTF-8 bytes are replaced with the Unicode replacement character
+// and an error is returned at the end indicating the presence of invalid UTF-8.
+func AppendQuote[Bytes ~[]byte | ~string](dst []byte, src Bytes) ([]byte, error) {
+	return jsonwire.AppendQuote(dst, src, &jsonflags.Flags{})
+}
+
+// AppendUnquote appends the decoded interpretation of src as a
+// double-quoted JSON string literal to dst and returns the extended buffer.
+// The input src must be a JSON string without any surrounding whitespace.
+// Invalid UTF-8 bytes are replaced with the Unicode replacement character
+// and an error is returned at the end indicating the presence of invalid UTF-8.
+// Any trailing bytes after the JSON string literal results in an error.
+func AppendUnquote[Bytes ~[]byte | ~string](dst []byte, src Bytes) ([]byte, error) {
+	return jsonwire.AppendUnquote(dst, src)
+}

vendor/github.com/go-json-experiment/json/jsontext/state.go

@@ -0,0 +1,715 @@
+// 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 jsontext
+
+import (
+	"math"
+	"strconv"
+
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+var (
+	errMissingName   = &SyntacticError{str: "missing string for object name"}
+	errMissingColon  = &SyntacticError{str: "missing character ':' after object name"}
+	errMissingValue  = &SyntacticError{str: "missing value after object name"}
+	errMissingComma  = &SyntacticError{str: "missing character ',' after object or array value"}
+	errMismatchDelim = &SyntacticError{str: "mismatching structural token for object or array"}
+	errMaxDepth      = &SyntacticError{str: "exceeded max depth"}
+
+	errInvalidNamespace = &SyntacticError{str: "object namespace is in an invalid state"}
+)
+
+// Per RFC 8259, section 9, implementations may enforce a maximum depth.
+// Such a limit is necessary to prevent stack overflows.
+const maxNestingDepth = 10000
+
+type state struct {
+	// Tokens validates whether the next token kind is valid.
+	Tokens stateMachine
+
+	// Names is a stack of object names.
+	// Not used if AllowDuplicateNames is true.
+	Names objectNameStack
+
+	// Namespaces is a stack of object namespaces.
+	// For performance reasons, Encoder or Decoder may not update this
+	// if Marshal or Unmarshal is able to track names in a more efficient way.
+	// See makeMapArshaler and makeStructArshaler.
+	// Not used if AllowDuplicateNames is true.
+	Namespaces objectNamespaceStack
+}
+
+func (s *state) reset() {
+	s.Tokens.reset()
+	s.Names.reset()
+	s.Namespaces.reset()
+}
+
+// appendStackPointer appends a JSON Pointer (RFC 6901) to the current value.
+// The returned pointer is only accurate if s.names is populated,
+// otherwise it uses the numeric index as the object member name.
+//
+// Invariant: Must call s.names.copyQuotedBuffer beforehand.
+func (s state) appendStackPointer(b []byte) []byte {
+	var objectDepth int
+	for i := 1; i < s.Tokens.Depth(); i++ {
+		e := s.Tokens.index(i)
+		if e.Length() == 0 {
+			break // empty object or array
+		}
+		b = append(b, '/')
+		switch {
+		case e.isObject():
+			if objectDepth < s.Names.length() {
+				for _, c := range s.Names.getUnquoted(objectDepth) {
+					// Per RFC 6901, section 3, escape '~' and '/' characters.
+					switch c {
+					case '~':
+						b = append(b, "~0"...)
+					case '/':
+						b = append(b, "~1"...)
+					default:
+						b = append(b, c)
+					}
+				}
+			} else {
+				// Since the names stack is unpopulated, the name is unknown.
+				// As a best-effort replacement, use the numeric member index.
+				// While inaccurate, it produces a syntactically valid pointer.
+				b = strconv.AppendUint(b, uint64((e.Length()-1)/2), 10)
+			}
+			objectDepth++
+		case e.isArray():
+			b = strconv.AppendUint(b, uint64(e.Length()-1), 10)
+		}
+	}
+	return b
+}
+
+// stateMachine is a push-down automaton that validates whether
+// a sequence of tokens is valid or not according to the JSON grammar.
+// It is useful for both encoding and decoding.
+//
+// It is a stack where each entry represents a nested JSON object or array.
+// The stack has a minimum depth of 1 where the first level is a
+// virtual JSON array to handle a stream of top-level JSON values.
+// The top-level virtual JSON array is special in that it doesn't require commas
+// between each JSON value.
+//
+// For performance, most methods are carefully written to be inlinable.
+// The zero value is a valid state machine ready for use.
+type stateMachine struct {
+	Stack []stateEntry
+	Last  stateEntry
+}
+
+// reset resets the state machine.
+// The machine always starts with a minimum depth of 1.
+func (m *stateMachine) reset() {
+	m.Stack = m.Stack[:0]
+	if cap(m.Stack) > 1<<10 {
+		m.Stack = nil
+	}
+	m.Last = stateTypeArray
+}
+
+// Depth is the current nested depth of JSON objects and arrays.
+// It is one-indexed (i.e., top-level values have a depth of 1).
+func (m stateMachine) Depth() int {
+	return len(m.Stack) + 1
+}
+
+// index returns a reference to the ith entry.
+// It is only valid until the next push method call.
+func (m *stateMachine) index(i int) *stateEntry {
+	if i == len(m.Stack) {
+		return &m.Last
+	}
+	return &m.Stack[i]
+}
+
+// DepthLength reports the current nested depth and
+// the length of the last JSON object or array.
+func (m stateMachine) DepthLength() (int, int) {
+	return m.Depth(), m.Last.Length()
+}
+
+// appendLiteral appends a JSON literal as the next token in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) appendLiteral() error {
+	switch {
+	case m.Last.NeedObjectName():
+		return errMissingName
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	default:
+		m.Last.Increment()
+		return nil
+	}
+}
+
+// appendString appends a JSON string as the next token in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) appendString() error {
+	switch {
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	default:
+		m.Last.Increment()
+		return nil
+	}
+}
+
+// appendNumber appends a JSON number as the next token in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) appendNumber() error {
+	return m.appendLiteral()
+}
+
+// pushObject appends a JSON start object token as next in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) pushObject() error {
+	switch {
+	case m.Last.NeedObjectName():
+		return errMissingName
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	case len(m.Stack) == maxNestingDepth:
+		return errMaxDepth
+	default:
+		m.Last.Increment()
+		m.Stack = append(m.Stack, m.Last)
+		m.Last = stateTypeObject
+		return nil
+	}
+}
+
+// popObject appends a JSON end object token as next in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) popObject() error {
+	switch {
+	case !m.Last.isObject():
+		return errMismatchDelim
+	case m.Last.needObjectValue():
+		return errMissingValue
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	default:
+		m.Last = m.Stack[len(m.Stack)-1]
+		m.Stack = m.Stack[:len(m.Stack)-1]
+		return nil
+	}
+}
+
+// pushArray appends a JSON start array token as next in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) pushArray() error {
+	switch {
+	case m.Last.NeedObjectName():
+		return errMissingName
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	case len(m.Stack) == maxNestingDepth:
+		return errMaxDepth
+	default:
+		m.Last.Increment()
+		m.Stack = append(m.Stack, m.Last)
+		m.Last = stateTypeArray
+		return nil
+	}
+}
+
+// popArray appends a JSON end array token as next in the sequence.
+// If an error is returned, the state is not mutated.
+func (m *stateMachine) popArray() error {
+	switch {
+	case !m.Last.isArray() || len(m.Stack) == 0: // forbid popping top-level virtual JSON array
+		return errMismatchDelim
+	case !m.Last.isValidNamespace():
+		return errInvalidNamespace
+	default:
+		m.Last = m.Stack[len(m.Stack)-1]
+		m.Stack = m.Stack[:len(m.Stack)-1]
+		return nil
+	}
+}
+
+// NeedIndent reports whether indent whitespace should be injected.
+// A zero value means that no whitespace should be injected.
+// A positive value means '\n', indentPrefix, and (n-1) copies of indentBody
+// should be appended to the output immediately before the next token.
+func (m stateMachine) NeedIndent(next Kind) (n int) {
+	willEnd := next == '}' || next == ']'
+	switch {
+	case m.Depth() == 1:
+		return 0 // top-level values are never indented
+	case m.Last.Length() == 0 && willEnd:
+		return 0 // an empty object or array is never indented
+	case m.Last.Length() == 0 || m.Last.needImplicitComma(next):
+		return m.Depth()
+	case willEnd:
+		return m.Depth() - 1
+	default:
+		return 0
+	}
+}
+
+// MayAppendDelim appends a colon or comma that may precede the next token.
+func (m stateMachine) MayAppendDelim(b []byte, next Kind) []byte {
+	switch {
+	case m.Last.needImplicitColon():
+		return append(b, ':')
+	case m.Last.needImplicitComma(next) && len(m.Stack) != 0: // comma not needed for top-level values
+		return append(b, ',')
+	default:
+		return b
+	}
+}
+
+// needDelim reports whether a colon or comma token should be implicitly emitted
+// before the next token of the specified kind.
+// A zero value means no delimiter should be emitted.
+func (m stateMachine) needDelim(next Kind) (delim byte) {
+	switch {
+	case m.Last.needImplicitColon():
+		return ':'
+	case m.Last.needImplicitComma(next) && len(m.Stack) != 0: // comma not needed for top-level values
+		return ','
+	default:
+		return 0
+	}
+}
+
+// checkDelim reports whether the specified delimiter should be there given
+// the kind of the next token that appears immediately afterwards.
+func (m stateMachine) checkDelim(delim byte, next Kind) error {
+	switch needDelim := m.needDelim(next); {
+	case needDelim == delim:
+		return nil
+	case needDelim == ':':
+		return errMissingColon
+	case needDelim == ',':
+		return errMissingComma
+	default:
+		return newInvalidCharacterError([]byte{delim}, "before next token")
+	}
+}
+
+// InvalidateDisabledNamespaces marks all disabled namespaces as invalid.
+//
+// For efficiency, Marshal and Unmarshal may disable namespaces since there are
+// more efficient ways to track duplicate names. However, if an error occurs,
+// the namespaces in Encoder or Decoder will be left in an inconsistent state.
+// Mark the namespaces as invalid so that future method calls on
+// Encoder or Decoder will return an error.
+func (m *stateMachine) InvalidateDisabledNamespaces() {
+	for i := 0; i < m.Depth(); i++ {
+		e := m.index(i)
+		if !e.isActiveNamespace() {
+			e.invalidateNamespace()
+		}
+	}
+}
+
+// stateEntry encodes several artifacts within a single unsigned integer:
+//   - whether this represents a JSON object or array,
+//   - whether this object should check for duplicate names, and
+//   - how many elements are in this JSON object or array.
+type stateEntry uint64
+
+const (
+	// The type mask (1 bit) records whether this is a JSON object or array.
+	stateTypeMask   stateEntry = 0x8000_0000_0000_0000
+	stateTypeObject stateEntry = 0x8000_0000_0000_0000
+	stateTypeArray  stateEntry = 0x0000_0000_0000_0000
+
+	// The name check mask (2 bit) records whether to update
+	// the namespaces for the current JSON object and
+	// whether the namespace is valid.
+	stateNamespaceMask    stateEntry = 0x6000_0000_0000_0000
+	stateDisableNamespace stateEntry = 0x4000_0000_0000_0000
+	stateInvalidNamespace stateEntry = 0x2000_0000_0000_0000
+
+	// The count mask (61 bits) records the number of elements.
+	stateCountMask    stateEntry = 0x1fff_ffff_ffff_ffff
+	stateCountLSBMask stateEntry = 0x0000_0000_0000_0001
+	stateCountOdd     stateEntry = 0x0000_0000_0000_0001
+	stateCountEven    stateEntry = 0x0000_0000_0000_0000
+)
+
+// Length reports the number of elements in the JSON object or array.
+// Each name and value in an object entry is treated as a separate element.
+func (e stateEntry) Length() int {
+	return int(e & stateCountMask)
+}
+
+// isObject reports whether this is a JSON object.
+func (e stateEntry) isObject() bool {
+	return e&stateTypeMask == stateTypeObject
+}
+
+// isArray reports whether this is a JSON array.
+func (e stateEntry) isArray() bool {
+	return e&stateTypeMask == stateTypeArray
+}
+
+// NeedObjectName reports whether the next token must be a JSON string,
+// which is necessary for JSON object names.
+func (e stateEntry) NeedObjectName() bool {
+	return e&(stateTypeMask|stateCountLSBMask) == stateTypeObject|stateCountEven
+}
+
+// needImplicitColon reports whether an colon should occur next,
+// which always occurs after JSON object names.
+func (e stateEntry) needImplicitColon() bool {
+	return e.needObjectValue()
+}
+
+// needObjectValue reports whether the next token must be a JSON value,
+// which is necessary after every JSON object name.
+func (e stateEntry) needObjectValue() bool {
+	return e&(stateTypeMask|stateCountLSBMask) == stateTypeObject|stateCountOdd
+}
+
+// needImplicitComma reports whether an comma should occur next,
+// which always occurs after a value in a JSON object or array
+// before the next value (or name).
+func (e stateEntry) needImplicitComma(next Kind) bool {
+	return !e.needObjectValue() && e.Length() > 0 && next != '}' && next != ']'
+}
+
+// Increment increments the number of elements for the current object or array.
+// This assumes that overflow won't practically be an issue since
+// 1<<bits.OnesCount(stateCountMask) is sufficiently large.
+func (e *stateEntry) Increment() {
+	(*e)++
+}
+
+// decrement decrements the number of elements for the current object or array.
+// It is the callers responsibility to ensure that e.length > 0.
+func (e *stateEntry) decrement() {
+	(*e)--
+}
+
+// DisableNamespace disables the JSON object namespace such that the
+// Encoder or Decoder no longer updates the namespace.
+func (e *stateEntry) DisableNamespace() {
+	*e |= stateDisableNamespace
+}
+
+// isActiveNamespace reports whether the JSON object namespace is actively
+// being updated and used for duplicate name checks.
+func (e stateEntry) isActiveNamespace() bool {
+	return e&(stateDisableNamespace) == 0
+}
+
+// invalidateNamespace marks the JSON object namespace as being invalid.
+func (e *stateEntry) invalidateNamespace() {
+	*e |= stateInvalidNamespace
+}
+
+// isValidNamespace reports whether the JSON object namespace is valid.
+func (e stateEntry) isValidNamespace() bool {
+	return e&(stateInvalidNamespace) == 0
+}
+
+// objectNameStack is a stack of names when descending into a JSON object.
+// In contrast to objectNamespaceStack, this only has to remember a single name
+// per JSON object.
+//
+// This data structure may contain offsets to encodeBuffer or decodeBuffer.
+// It violates clean abstraction of layers, but is significantly more efficient.
+// This ensures that popping and pushing in the common case is a trivial
+// push/pop of an offset integer.
+//
+// The zero value is an empty names stack ready for use.
+type objectNameStack struct {
+	// offsets is a stack of offsets for each name.
+	// A non-negative offset is the ending offset into the local names buffer.
+	// A negative offset is the bit-wise inverse of a starting offset into
+	// a remote buffer (e.g., encodeBuffer or decodeBuffer).
+	// A math.MinInt offset at the end implies that the last object is empty.
+	// Invariant: Positive offsets always occur before negative offsets.
+	offsets []int
+	// unquotedNames is a back-to-back concatenation of names.
+	unquotedNames []byte
+}
+
+func (ns *objectNameStack) reset() {
+	ns.offsets = ns.offsets[:0]
+	ns.unquotedNames = ns.unquotedNames[:0]
+	if cap(ns.offsets) > 1<<6 {
+		ns.offsets = nil // avoid pinning arbitrarily large amounts of memory
+	}
+	if cap(ns.unquotedNames) > 1<<10 {
+		ns.unquotedNames = nil // avoid pinning arbitrarily large amounts of memory
+	}
+}
+
+func (ns *objectNameStack) length() int {
+	return len(ns.offsets)
+}
+
+// getUnquoted retrieves the ith unquoted name in the namespace.
+// It returns an empty string if the last object is empty.
+//
+// Invariant: Must call copyQuotedBuffer beforehand.
+func (ns *objectNameStack) getUnquoted(i int) []byte {
+	ns.ensureCopiedBuffer()
+	if i == 0 {
+		return ns.unquotedNames[:ns.offsets[0]]
+	} else {
+		return ns.unquotedNames[ns.offsets[i-1]:ns.offsets[i-0]]
+	}
+}
+
+// invalidOffset indicates that the last JSON object currently has no name.
+const invalidOffset = math.MinInt
+
+// push descends into a nested JSON object.
+func (ns *objectNameStack) push() {
+	ns.offsets = append(ns.offsets, invalidOffset)
+}
+
+// ReplaceLastQuotedOffset replaces the last name with the starting offset
+// to the quoted name in some remote buffer. All offsets provided must be
+// relative to the same buffer until copyQuotedBuffer is called.
+func (ns *objectNameStack) ReplaceLastQuotedOffset(i int) {
+	// Use bit-wise inversion instead of naive multiplication by -1 to avoid
+	// ambiguity regarding zero (which is a valid offset into the names field).
+	// Bit-wise inversion is mathematically equivalent to -i-1,
+	// such that 0 becomes -1, 1 becomes -2, and so forth.
+	// This ensures that remote offsets are always negative.
+	ns.offsets[len(ns.offsets)-1] = ^i
+}
+
+// replaceLastUnquotedName replaces the last name with the provided name.
+//
+// Invariant: Must call copyQuotedBuffer beforehand.
+func (ns *objectNameStack) replaceLastUnquotedName(s string) {
+	ns.ensureCopiedBuffer()
+	var startOffset int
+	if len(ns.offsets) > 1 {
+		startOffset = ns.offsets[len(ns.offsets)-2]
+	}
+	ns.unquotedNames = append(ns.unquotedNames[:startOffset], s...)
+	ns.offsets[len(ns.offsets)-1] = len(ns.unquotedNames)
+}
+
+// clearLast removes any name in the last JSON object.
+// It is semantically equivalent to ns.push followed by ns.pop.
+func (ns *objectNameStack) clearLast() {
+	ns.offsets[len(ns.offsets)-1] = invalidOffset
+}
+
+// pop ascends out of a nested JSON object.
+func (ns *objectNameStack) pop() {
+	ns.offsets = ns.offsets[:len(ns.offsets)-1]
+}
+
+// copyQuotedBuffer copies names from the remote buffer into the local names
+// buffer so that there are no more offset references into the remote buffer.
+// This allows the remote buffer to change contents without affecting
+// the names that this data structure is trying to remember.
+func (ns *objectNameStack) copyQuotedBuffer(b []byte) {
+	// Find the first negative offset.
+	var i int
+	for i = len(ns.offsets) - 1; i >= 0 && ns.offsets[i] < 0; i-- {
+		continue
+	}
+
+	// Copy each name from the remote buffer into the local buffer.
+	for i = i + 1; i < len(ns.offsets); i++ {
+		if i == len(ns.offsets)-1 && ns.offsets[i] == invalidOffset {
+			if i == 0 {
+				ns.offsets[i] = 0
+			} else {
+				ns.offsets[i] = ns.offsets[i-1]
+			}
+			break // last JSON object had a push without any names
+		}
+
+		// As a form of Hyrum proofing, we write an invalid character into the
+		// buffer to make misuse of Decoder.ReadToken more obvious.
+		// We need to undo that mutation here.
+		quotedName := b[^ns.offsets[i]:]
+		if quotedName[0] == invalidateBufferByte {
+			quotedName[0] = '"'
+		}
+
+		// Append the unquoted name to the local buffer.
+		var startOffset int
+		if i > 0 {
+			startOffset = ns.offsets[i-1]
+		}
+		if n := jsonwire.ConsumeSimpleString(quotedName); n > 0 {
+			ns.unquotedNames = append(ns.unquotedNames[:startOffset], quotedName[len(`"`):n-len(`"`)]...)
+		} else {
+			ns.unquotedNames, _ = jsonwire.AppendUnquote(ns.unquotedNames[:startOffset], quotedName)
+		}
+		ns.offsets[i] = len(ns.unquotedNames)
+	}
+}
+
+func (ns *objectNameStack) ensureCopiedBuffer() {
+	if len(ns.offsets) > 0 && ns.offsets[len(ns.offsets)-1] < 0 {
+		panic("BUG: copyQuotedBuffer not called beforehand")
+	}
+}
+
+// objectNamespaceStack is a stack of object namespaces.
+// This data structure assists in detecting duplicate names.
+type objectNamespaceStack []objectNamespace
+
+// reset resets the object namespace stack.
+func (nss *objectNamespaceStack) reset() {
+	if cap(*nss) > 1<<10 {
+		*nss = nil
+	}
+	*nss = (*nss)[:0]
+}
+
+// push starts a new namespace for a nested JSON object.
+func (nss *objectNamespaceStack) push() {
+	if cap(*nss) > len(*nss) {
+		*nss = (*nss)[:len(*nss)+1]
+		nss.Last().reset()
+	} else {
+		*nss = append(*nss, objectNamespace{})
+	}
+}
+
+// Last returns a pointer to the last JSON object namespace.
+func (nss objectNamespaceStack) Last() *objectNamespace {
+	return &nss[len(nss)-1]
+}
+
+// pop terminates the namespace for a nested JSON object.
+func (nss *objectNamespaceStack) pop() {
+	*nss = (*nss)[:len(*nss)-1]
+}
+
+// objectNamespace is the namespace for a JSON object.
+// In contrast to objectNameStack, this needs to remember a all names
+// per JSON object.
+//
+// The zero value is an empty namespace ready for use.
+type objectNamespace struct {
+	// It relies on a linear search over all the names before switching
+	// to use a Go map for direct lookup.
+
+	// endOffsets is a list of offsets to the end of each name in buffers.
+	// The length of offsets is the number of names in the namespace.
+	endOffsets []uint
+	// allUnquotedNames is a back-to-back concatenation of every name in the namespace.
+	allUnquotedNames []byte
+	// mapNames is a Go map containing every name in the namespace.
+	// Only valid if non-nil.
+	mapNames map[string]struct{}
+}
+
+// reset resets the namespace to be empty.
+func (ns *objectNamespace) reset() {
+	ns.endOffsets = ns.endOffsets[:0]
+	ns.allUnquotedNames = ns.allUnquotedNames[:0]
+	ns.mapNames = nil
+	if cap(ns.endOffsets) > 1<<6 {
+		ns.endOffsets = nil // avoid pinning arbitrarily large amounts of memory
+	}
+	if cap(ns.allUnquotedNames) > 1<<10 {
+		ns.allUnquotedNames = nil // avoid pinning arbitrarily large amounts of memory
+	}
+}
+
+// length reports the number of names in the namespace.
+func (ns *objectNamespace) length() int {
+	return len(ns.endOffsets)
+}
+
+// getUnquoted retrieves the ith unquoted name in the namespace.
+func (ns *objectNamespace) getUnquoted(i int) []byte {
+	if i == 0 {
+		return ns.allUnquotedNames[:ns.endOffsets[0]]
+	} else {
+		return ns.allUnquotedNames[ns.endOffsets[i-1]:ns.endOffsets[i-0]]
+	}
+}
+
+// lastUnquoted retrieves the last name in the namespace.
+func (ns *objectNamespace) lastUnquoted() []byte {
+	return ns.getUnquoted(ns.length() - 1)
+}
+
+// insertQuoted inserts a name and reports whether it was inserted,
+// which only occurs if name is not already in the namespace.
+// The provided name must be a valid JSON string.
+func (ns *objectNamespace) insertQuoted(name []byte, isVerbatim bool) bool {
+	if isVerbatim {
+		name = name[len(`"`) : len(name)-len(`"`)]
+	}
+	return ns.insert(name, !isVerbatim)
+}
+func (ns *objectNamespace) InsertUnquoted(name []byte) bool {
+	return ns.insert(name, false)
+}
+func (ns *objectNamespace) insert(name []byte, quoted bool) bool {
+	var allNames []byte
+	if quoted {
+		allNames, _ = jsonwire.AppendUnquote(ns.allUnquotedNames, name)
+	} else {
+		allNames = append(ns.allUnquotedNames, name...)
+	}
+	name = allNames[len(ns.allUnquotedNames):]
+
+	// Switch to a map if the buffer is too large for linear search.
+	// This does not add the current name to the map.
+	if ns.mapNames == nil && (ns.length() > 64 || len(ns.allUnquotedNames) > 1024) {
+		ns.mapNames = make(map[string]struct{})
+		var startOffset uint
+		for _, endOffset := range ns.endOffsets {
+			name := ns.allUnquotedNames[startOffset:endOffset]
+			ns.mapNames[string(name)] = struct{}{} // allocates a new string
+			startOffset = endOffset
+		}
+	}
+
+	if ns.mapNames == nil {
+		// Perform linear search over the buffer to find matching names.
+		// It provides O(n) lookup, but does not require any allocations.
+		var startOffset uint
+		for _, endOffset := range ns.endOffsets {
+			if string(ns.allUnquotedNames[startOffset:endOffset]) == string(name) {
+				return false
+			}
+			startOffset = endOffset
+		}
+	} else {
+		// Use the map if it is populated.
+		// It provides O(1) lookup, but requires a string allocation per name.
+		if _, ok := ns.mapNames[string(name)]; ok {
+			return false
+		}
+		ns.mapNames[string(name)] = struct{}{} // allocates a new string
+	}
+
+	ns.allUnquotedNames = allNames
+	ns.endOffsets = append(ns.endOffsets, uint(len(ns.allUnquotedNames)))
+	return true
+}
+
+// removeLast removes the last name in the namespace.
+func (ns *objectNamespace) removeLast() {
+	if ns.mapNames != nil {
+		delete(ns.mapNames, string(ns.lastUnquoted()))
+	}
+	if ns.length()-1 == 0 {
+		ns.endOffsets = ns.endOffsets[:0]
+		ns.allUnquotedNames = ns.allUnquotedNames[:0]
+	} else {
+		ns.endOffsets = ns.endOffsets[:ns.length()-1]
+		ns.allUnquotedNames = ns.allUnquotedNames[:ns.endOffsets[ns.length()-1]]
+	}
+}

vendor/github.com/go-json-experiment/json/jsontext/token.go

@@ -0,0 +1,525 @@
+// 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 jsontext
+
+import (
+	"math"
+	"strconv"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+// NOTE: Token is analogous to v1 json.Token.
+
+const (
+	maxInt64  = math.MaxInt64
+	minInt64  = math.MinInt64
+	maxUint64 = math.MaxUint64
+	minUint64 = 0 // for consistency and readability purposes
+
+	invalidTokenPanic = "invalid json.Token; it has been voided by a subsequent json.Decoder call"
+)
+
+// Token represents a lexical JSON token, which may be one of the following:
+//   - a JSON literal (i.e., null, true, or false)
+//   - a JSON string (e.g., "hello, world!")
+//   - a JSON number (e.g., 123.456)
+//   - a start or end delimiter for a JSON object (i.e., { or } )
+//   - a start or end delimiter for a JSON array (i.e., [ or ] )
+//
+// A Token cannot represent entire array or object values, while a [Value] can.
+// There is no Token to represent commas and colons since
+// these structural tokens can be inferred from the surrounding context.
+type Token struct {
+	nonComparable
+
+	// Tokens can exist in either a "raw" or an "exact" form.
+	// Tokens produced by the Decoder are in the "raw" form.
+	// Tokens returned by constructors are usually in the "exact" form.
+	// The Encoder accepts Tokens in either the "raw" or "exact" form.
+	//
+	// The following chart shows the possible values for each Token type:
+	//	╔═════════════════╦════════════╤════════════╤════════════╗
+	//	║ Token type      ║ raw field  │ str field  │ num field  ║
+	//	╠═════════════════╬════════════╪════════════╪════════════╣
+	//	║ null   (raw)    ║ "null"     │ ""         │ 0          ║
+	//	║ false  (raw)    ║ "false"    │ ""         │ 0          ║
+	//	║ true   (raw)    ║ "true"     │ ""         │ 0          ║
+	//	║ string (raw)    ║ non-empty  │ ""         │ offset     ║
+	//	║ string (string) ║ nil        │ non-empty  │ 0          ║
+	//	║ number (raw)    ║ non-empty  │ ""         │ offset     ║
+	//	║ number (float)  ║ nil        │ "f"        │ non-zero   ║
+	//	║ number (int64)  ║ nil        │ "i"        │ non-zero   ║
+	//	║ number (uint64) ║ nil        │ "u"        │ non-zero   ║
+	//	║ object (delim)  ║ "{" or "}" │ ""         │ 0          ║
+	//	║ array  (delim)  ║ "[" or "]" │ ""         │ 0          ║
+	//	╚═════════════════╩════════════╧════════════╧════════════╝
+	//
+	// Notes:
+	//   - For tokens stored in "raw" form, the num field contains the
+	//     absolute offset determined by raw.previousOffsetStart().
+	//     The buffer itself is stored in raw.previousBuffer().
+	//   - JSON literals and structural characters are always in the "raw" form.
+	//   - JSON strings and numbers can be in either "raw" or "exact" forms.
+	//   - The exact zero value of JSON strings and numbers in the "exact" forms
+	//     have ambiguous representation. Thus, they are always represented
+	//     in the "raw" form.
+
+	// raw contains a reference to the raw decode buffer.
+	// If non-nil, then its value takes precedence over str and num.
+	// It is only valid if num == raw.previousOffsetStart().
+	raw *decodeBuffer
+
+	// str is the unescaped JSON string if num is zero.
+	// Otherwise, it is "f", "i", or "u" if num should be interpreted
+	// as a float64, int64, or uint64, respectively.
+	str string
+
+	// num is a float64, int64, or uint64 stored as a uint64 value.
+	// It is non-zero for any JSON number in the "exact" form.
+	num uint64
+}
+
+// TODO: Does representing 1-byte delimiters as *decodeBuffer cause performance issues?
+
+var (
+	Null  Token = rawToken("null")
+	False Token = rawToken("false")
+	True  Token = rawToken("true")
+
+	ObjectStart Token = rawToken("{")
+	ObjectEnd   Token = rawToken("}")
+	ArrayStart  Token = rawToken("[")
+	ArrayEnd    Token = rawToken("]")
+
+	zeroString Token = rawToken(`""`)
+	zeroNumber Token = rawToken(`0`)
+
+	nanString  Token = String("NaN")
+	pinfString Token = String("Infinity")
+	ninfString Token = String("-Infinity")
+)
+
+func rawToken(s string) Token {
+	return Token{raw: &decodeBuffer{buf: []byte(s), prevStart: 0, prevEnd: len(s)}}
+}
+
+// Bool constructs a Token representing a JSON boolean.
+func Bool(b bool) Token {
+	if b {
+		return True
+	}
+	return False
+}
+
+// String constructs a Token representing a JSON string.
+// The provided string should contain valid UTF-8, otherwise invalid characters
+// may be mangled as the Unicode replacement character.
+func String(s string) Token {
+	if len(s) == 0 {
+		return zeroString
+	}
+	return Token{str: s}
+}
+
+// Float constructs a Token representing a JSON number.
+// The values NaN, +Inf, and -Inf will be represented
+// as a JSON string with the values "NaN", "Infinity", and "-Infinity".
+func Float(n float64) Token {
+	switch {
+	case math.Float64bits(n) == 0:
+		return zeroNumber
+	case math.IsNaN(n):
+		return nanString
+	case math.IsInf(n, +1):
+		return pinfString
+	case math.IsInf(n, -1):
+		return ninfString
+	}
+	return Token{str: "f", num: math.Float64bits(n)}
+}
+
+// Int constructs a Token representing a JSON number from an int64.
+func Int(n int64) Token {
+	if n == 0 {
+		return zeroNumber
+	}
+	return Token{str: "i", num: uint64(n)}
+}
+
+// Uint constructs a Token representing a JSON number from a uint64.
+func Uint(n uint64) Token {
+	if n == 0 {
+		return zeroNumber
+	}
+	return Token{str: "u", num: uint64(n)}
+}
+
+// Clone makes a copy of the Token such that its value remains valid
+// even after a subsequent [Decoder.Read] call.
+func (t Token) Clone() Token {
+	// TODO: Allow caller to avoid any allocations?
+	if raw := t.raw; raw != nil {
+		// Avoid copying globals.
+		if t.raw.prevStart == 0 {
+			switch t.raw {
+			case Null.raw:
+				return Null
+			case False.raw:
+				return False
+			case True.raw:
+				return True
+			case ObjectStart.raw:
+				return ObjectStart
+			case ObjectEnd.raw:
+				return ObjectEnd
+			case ArrayStart.raw:
+				return ArrayStart
+			case ArrayEnd.raw:
+				return ArrayEnd
+			}
+		}
+
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		// TODO(https://go.dev/issue/45038): Use bytes.Clone.
+		buf := append([]byte(nil), raw.PreviousBuffer()...)
+		return Token{raw: &decodeBuffer{buf: buf, prevStart: 0, prevEnd: len(buf)}}
+	}
+	return t
+}
+
+// Bool returns the value for a JSON boolean.
+// It panics if the token kind is not a JSON boolean.
+func (t Token) Bool() bool {
+	switch t.raw {
+	case True.raw:
+		return true
+	case False.raw:
+		return false
+	default:
+		panic("invalid JSON token kind: " + t.Kind().String())
+	}
+}
+
+// appendString appends a JSON string to dst and returns it.
+// It panics if t is not a JSON string.
+func (t Token) appendString(dst []byte, flags *jsonflags.Flags) ([]byte, error) {
+	if raw := t.raw; raw != nil {
+		// Handle raw string value.
+		buf := raw.PreviousBuffer()
+		if Kind(buf[0]) == '"' {
+			if jsonwire.ConsumeSimpleString(buf) == len(buf) {
+				return append(dst, buf...), nil
+			}
+			dst, _, err := jsonwire.ReformatString(dst, buf, flags)
+			return dst, err
+		}
+	} else if len(t.str) != 0 && t.num == 0 {
+		// Handle exact string value.
+		return jsonwire.AppendQuote(dst, t.str, flags)
+	}
+
+	panic("invalid JSON token kind: " + t.Kind().String())
+}
+
+// String returns the unescaped string value for a JSON string.
+// For other JSON kinds, this returns the raw JSON representation.
+func (t Token) String() string {
+	// This is inlinable to take advantage of "function outlining".
+	// This avoids an allocation for the string(b) conversion
+	// if the caller does not use the string in an escaping manner.
+	// See https://blog.filippo.io/efficient-go-apis-with-the-inliner/
+	s, b := t.string()
+	if len(b) > 0 {
+		return string(b)
+	}
+	return s
+}
+func (t Token) string() (string, []byte) {
+	if raw := t.raw; raw != nil {
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		buf := raw.PreviousBuffer()
+		if buf[0] == '"' {
+			// TODO: Preserve ValueFlags in Token?
+			isVerbatim := jsonwire.ConsumeSimpleString(buf) == len(buf)
+			return "", jsonwire.UnquoteMayCopy(buf, isVerbatim)
+		}
+		// Handle tokens that are not JSON strings for fmt.Stringer.
+		return "", buf
+	}
+	if len(t.str) != 0 && t.num == 0 {
+		return t.str, nil
+	}
+	// Handle tokens that are not JSON strings for fmt.Stringer.
+	if t.num > 0 {
+		switch t.str[0] {
+		case 'f':
+			return string(jsonwire.AppendFloat(nil, math.Float64frombits(t.num), 64)), nil
+		case 'i':
+			return strconv.FormatInt(int64(t.num), 10), nil
+		case 'u':
+			return strconv.FormatUint(uint64(t.num), 10), nil
+		}
+	}
+	return "<invalid json.Token>", nil
+}
+
+// appendNumber appends a JSON number to dst and returns it.
+// It panics if t is not a JSON number.
+func (t Token) appendNumber(dst []byte, canonicalize bool) ([]byte, error) {
+	if raw := t.raw; raw != nil {
+		// Handle raw number value.
+		buf := raw.PreviousBuffer()
+		if Kind(buf[0]).normalize() == '0' {
+			if !canonicalize {
+				return append(dst, buf...), nil
+			}
+			dst, _, err := jsonwire.ReformatNumber(dst, buf, canonicalize)
+			return dst, err
+		}
+	} else if t.num != 0 {
+		// Handle exact number value.
+		switch t.str[0] {
+		case 'f':
+			return jsonwire.AppendFloat(dst, math.Float64frombits(t.num), 64), nil
+		case 'i':
+			return strconv.AppendInt(dst, int64(t.num), 10), nil
+		case 'u':
+			return strconv.AppendUint(dst, uint64(t.num), 10), nil
+		}
+	}
+
+	panic("invalid JSON token kind: " + t.Kind().String())
+}
+
+// Float returns the floating-point value for a JSON number.
+// It returns a NaN, +Inf, or -Inf value for any JSON string
+// with the values "NaN", "Infinity", or "-Infinity".
+// It panics for all other cases.
+func (t Token) Float() float64 {
+	if raw := t.raw; raw != nil {
+		// Handle raw number value.
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		buf := raw.PreviousBuffer()
+		if Kind(buf[0]).normalize() == '0' {
+			fv, _ := jsonwire.ParseFloat(buf, 64)
+			return fv
+		}
+	} else if t.num != 0 {
+		// Handle exact number value.
+		switch t.str[0] {
+		case 'f':
+			return math.Float64frombits(t.num)
+		case 'i':
+			return float64(int64(t.num))
+		case 'u':
+			return float64(uint64(t.num))
+		}
+	}
+
+	// Handle string values with "NaN", "Infinity", or "-Infinity".
+	if t.Kind() == '"' {
+		switch t.String() {
+		case "NaN":
+			return math.NaN()
+		case "Infinity":
+			return math.Inf(+1)
+		case "-Infinity":
+			return math.Inf(-1)
+		}
+	}
+
+	panic("invalid JSON token kind: " + t.Kind().String())
+}
+
+// Int returns the signed integer value for a JSON number.
+// The fractional component of any number is ignored (truncation toward zero).
+// Any number beyond the representation of an int64 will be saturated
+// to the closest representable value.
+// It panics if the token kind is not a JSON number.
+func (t Token) Int() int64 {
+	if raw := t.raw; raw != nil {
+		// Handle raw integer value.
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		neg := false
+		buf := raw.PreviousBuffer()
+		if len(buf) > 0 && buf[0] == '-' {
+			neg, buf = true, buf[1:]
+		}
+		if numAbs, ok := jsonwire.ParseUint(buf); ok {
+			if neg {
+				if numAbs > -minInt64 {
+					return minInt64
+				}
+				return -1 * int64(numAbs)
+			} else {
+				if numAbs > +maxInt64 {
+					return maxInt64
+				}
+				return +1 * int64(numAbs)
+			}
+		}
+	} else if t.num != 0 {
+		// Handle exact integer value.
+		switch t.str[0] {
+		case 'i':
+			return int64(t.num)
+		case 'u':
+			if t.num > maxInt64 {
+				return maxInt64
+			}
+			return int64(t.num)
+		}
+	}
+
+	// Handle JSON number that is a floating-point value.
+	if t.Kind() == '0' {
+		switch fv := t.Float(); {
+		case fv >= maxInt64:
+			return maxInt64
+		case fv <= minInt64:
+			return minInt64
+		default:
+			return int64(fv) // truncation toward zero
+		}
+	}
+
+	panic("invalid JSON token kind: " + t.Kind().String())
+}
+
+// Uint returns the unsigned integer value for a JSON number.
+// The fractional component of any number is ignored (truncation toward zero).
+// Any number beyond the representation of an uint64 will be saturated
+// to the closest representable value.
+// It panics if the token kind is not a JSON number.
+func (t Token) Uint() uint64 {
+	// NOTE: This accessor returns 0 for any negative JSON number,
+	// which might be surprising, but is at least consistent with the behavior
+	// of saturating out-of-bounds numbers to the closest representable number.
+
+	if raw := t.raw; raw != nil {
+		// Handle raw integer value.
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		neg := false
+		buf := raw.PreviousBuffer()
+		if len(buf) > 0 && buf[0] == '-' {
+			neg, buf = true, buf[1:]
+		}
+		if num, ok := jsonwire.ParseUint(buf); ok {
+			if neg {
+				return minUint64
+			}
+			return num
+		}
+	} else if t.num != 0 {
+		// Handle exact integer value.
+		switch t.str[0] {
+		case 'u':
+			return t.num
+		case 'i':
+			if int64(t.num) < minUint64 {
+				return minUint64
+			}
+			return uint64(int64(t.num))
+		}
+	}
+
+	// Handle JSON number that is a floating-point value.
+	if t.Kind() == '0' {
+		switch fv := t.Float(); {
+		case fv >= maxUint64:
+			return maxUint64
+		case fv <= minUint64:
+			return minUint64
+		default:
+			return uint64(fv) // truncation toward zero
+		}
+	}
+
+	panic("invalid JSON token kind: " + t.Kind().String())
+}
+
+// Kind returns the token kind.
+func (t Token) Kind() Kind {
+	switch {
+	case t.raw != nil:
+		raw := t.raw
+		if uint64(raw.previousOffsetStart()) != t.num {
+			panic(invalidTokenPanic)
+		}
+		return Kind(t.raw.buf[raw.prevStart]).normalize()
+	case t.num != 0:
+		return '0'
+	case len(t.str) != 0:
+		return '"'
+	default:
+		return invalidKind
+	}
+}
+
+// Kind represents each possible JSON token kind with a single byte,
+// which is conveniently the first byte of that kind's grammar
+// with the restriction that numbers always be represented with '0':
+//
+//   - 'n': null
+//   - 'f': false
+//   - 't': true
+//   - '"': string
+//   - '0': number
+//   - '{': object start
+//   - '}': object end
+//   - '[': array start
+//   - ']': array end
+//
+// An invalid kind is usually represented using 0,
+// but may be non-zero due to invalid JSON data.
+type Kind byte
+
+const invalidKind Kind = 0
+
+// String prints the kind in a humanly readable fashion.
+func (k Kind) String() string {
+	switch k {
+	case 'n':
+		return "null"
+	case 'f':
+		return "false"
+	case 't':
+		return "true"
+	case '"':
+		return "string"
+	case '0':
+		return "number"
+	case '{':
+		return "{"
+	case '}':
+		return "}"
+	case '[':
+		return "["
+	case ']':
+		return "]"
+	default:
+		return "<invalid json.Kind: " + jsonwire.QuoteRune(string(k)) + ">"
+	}
+}
+
+// normalize coalesces all possible starting characters of a number as just '0'.
+func (k Kind) normalize() Kind {
+	if k == '-' || ('0' <= k && k <= '9') {
+		return '0'
+	}
+	return k
+}

vendor/github.com/go-json-experiment/json/jsontext/value.go

@@ -0,0 +1,305 @@
+// 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 jsontext
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"slices"
+	"strings"
+	"sync"
+
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonwire"
+)
+
+// NOTE: Value is analogous to v1 json.RawMessage.
+
+// Value represents a single raw JSON value, which may be one of the following:
+//   - a JSON literal (i.e., null, true, or false)
+//   - a JSON string (e.g., "hello, world!")
+//   - a JSON number (e.g., 123.456)
+//   - an entire JSON object (e.g., {"fizz":"buzz"} )
+//   - an entire JSON array (e.g., [1,2,3] )
+//
+// Value can represent entire array or object values, while [Token] cannot.
+// Value may contain leading and/or trailing whitespace.
+type Value []byte
+
+// Clone returns a copy of v.
+func (v Value) Clone() Value {
+	return bytes.Clone(v)
+}
+
+// String returns the string formatting of v.
+func (v Value) String() string {
+	if v == nil {
+		return "null"
+	}
+	return string(v)
+}
+
+// IsValid reports whether the raw JSON value is syntactically valid
+// according to RFC 7493.
+//
+// It verifies whether the input is properly encoded as UTF-8,
+// that escape sequences within strings decode to valid Unicode codepoints, and
+// that all names in each object are unique.
+// It does not verify whether numbers are representable within the limits
+// of any common numeric type (e.g., float64, int64, or uint64).
+func (v Value) IsValid() bool {
+	d := getBufferedDecoder(v)
+	defer putBufferedDecoder(d)
+	_, errVal := d.ReadValue()
+	_, errEOF := d.ReadToken()
+	return errVal == nil && errEOF == io.EOF
+}
+
+// Compact removes all whitespace from the raw JSON value.
+//
+// It does not reformat JSON strings to use any other representation.
+// It is guaranteed to succeed if the input is valid.
+// If the value is already compacted, then the buffer is not mutated.
+func (v *Value) Compact() error {
+	return v.reformat(false, false, "", "")
+}
+
+// Indent reformats the whitespace in the raw JSON value so that each element
+// in a JSON object or array begins on a new, indented line beginning with
+// prefix followed by one or more copies of indent according to the nesting.
+// The value does not begin with the prefix nor any indention,
+// to make it easier to embed inside other formatted JSON data.
+//
+// It does not reformat JSON strings to use any other representation.
+// It is guaranteed to succeed if the input is valid.
+// If the value is already indented properly, then the buffer is not mutated.
+//
+// The prefix and indent strings must be composed of only spaces and/or tabs.
+func (v *Value) Indent(prefix, indent string) error {
+	return v.reformat(false, true, prefix, indent)
+}
+
+// Canonicalize canonicalizes the raw JSON value according to the
+// JSON Canonicalization Scheme (JCS) as defined by RFC 8785
+// where it produces a stable representation of a JSON value.
+//
+// The output stability is dependent on the stability of the application data
+// (see RFC 8785, Appendix E). It cannot produce stable output from
+// fundamentally unstable input. For example, if the JSON value
+// contains ephemeral data (e.g., a frequently changing timestamp),
+// then the value is still unstable regardless of whether this is called.
+//
+// Note that JCS treats all JSON numbers as IEEE 754 double precision numbers.
+// Any numbers with precision beyond what is representable by that form
+// will lose their precision when canonicalized. For example, integer values
+// beyond ±2⁵³ will lose their precision. It is recommended that
+// int64 and uint64 data types be represented as a JSON string.
+//
+// It is guaranteed to succeed if the input is valid.
+// If the value is already canonicalized, then the buffer is not mutated.
+func (v *Value) Canonicalize() error {
+	return v.reformat(true, false, "", "")
+}
+
+// TODO: Instead of implementing the v1 Marshaler/Unmarshaler,
+// consider implementing the v2 versions instead.
+
+// MarshalJSON returns v as the JSON encoding of v.
+// It returns the stored value as the raw JSON output without any validation.
+// If v is nil, then this returns a JSON null.
+func (v Value) MarshalJSON() ([]byte, error) {
+	// NOTE: This matches the behavior of v1 json.RawMessage.MarshalJSON.
+	if v == nil {
+		return []byte("null"), nil
+	}
+	return v, nil
+}
+
+// UnmarshalJSON sets v as the JSON encoding of b.
+// It stores a copy of the provided raw JSON input without any validation.
+func (v *Value) UnmarshalJSON(b []byte) error {
+	// NOTE: This matches the behavior of v1 json.RawMessage.UnmarshalJSON.
+	if v == nil {
+		return errors.New("json.Value: UnmarshalJSON on nil pointer")
+	}
+	*v = append((*v)[:0], b...)
+	return nil
+}
+
+// Kind returns the starting token kind.
+// For a valid value, this will never include '}' or ']'.
+func (v Value) Kind() Kind {
+	if v := v[jsonwire.ConsumeWhitespace(v):]; len(v) > 0 {
+		return Kind(v[0]).normalize()
+	}
+	return invalidKind
+}
+
+func (v *Value) reformat(canonical, multiline bool, prefix, indent string) error {
+	// Write the entire value to reformat all tokens and whitespace.
+	e := getBufferedEncoder()
+	defer putBufferedEncoder(e)
+	eo := &e.s.Struct
+	if canonical {
+		eo.Flags.Set(jsonflags.AllowInvalidUTF8 | 0)    // per RFC 8785, section 3.2.4
+		eo.Flags.Set(jsonflags.AllowDuplicateNames | 0) // per RFC 8785, section 3.1
+		eo.Flags.Set(jsonflags.CanonicalizeNumbers | 1) // per RFC 8785, section 3.2.2.3
+		eo.Flags.Set(jsonflags.PreserveRawStrings | 0)  // per RFC 8785, section 3.2.2.2
+		eo.Flags.Set(jsonflags.EscapeForHTML | 0)       // per RFC 8785, section 3.2.2.2
+		eo.Flags.Set(jsonflags.EscapeForJS | 0)         // per RFC 8785, section 3.2.2.2
+		eo.Flags.Set(jsonflags.Expand | 0)              // per RFC 8785, section 3.2.1
+	} else {
+		if s := strings.TrimLeft(prefix, " \t"); len(s) > 0 {
+			panic("json: invalid character " + jsonwire.QuoteRune(s) + " in indent prefix")
+		}
+		if s := strings.TrimLeft(indent, " \t"); len(s) > 0 {
+			panic("json: invalid character " + jsonwire.QuoteRune(s) + " in indent")
+		}
+		eo.Flags.Set(jsonflags.AllowInvalidUTF8 | 1)
+		eo.Flags.Set(jsonflags.AllowDuplicateNames | 1)
+		eo.Flags.Set(jsonflags.PreserveRawStrings | 1)
+		if multiline {
+			eo.Flags.Set(jsonflags.Expand | 1)
+			eo.Flags.Set(jsonflags.Indent | 1)
+			eo.Flags.Set(jsonflags.IndentPrefix | 1)
+			eo.IndentPrefix = prefix
+			eo.Indent = indent
+		} else {
+			eo.Flags.Set(jsonflags.Expand | 0)
+		}
+	}
+	eo.Flags.Set(jsonflags.OmitTopLevelNewline | 1)
+	if err := e.s.WriteValue(*v); err != nil {
+		return err
+	}
+
+	// For canonical output, we may need to reorder object members.
+	if canonical {
+		// Obtain a buffered encoder just to use its internal buffer as
+		// a scratch buffer in reorderObjects for reordering object members.
+		e2 := getBufferedEncoder()
+		defer putBufferedEncoder(e2)
+
+		// Disable redundant checks performed earlier during encoding.
+		d := getBufferedDecoder(e.s.Buf)
+		defer putBufferedDecoder(d)
+		d.s.Flags.Set(jsonflags.AllowDuplicateNames | jsonflags.AllowInvalidUTF8 | 1)
+		reorderObjects(d, &e2.s.Buf) // per RFC 8785, section 3.2.3
+	}
+
+	// Store the result back into the value if different.
+	if !bytes.Equal(*v, e.s.Buf) {
+		*v = append((*v)[:0], e.s.Buf...)
+	}
+	return nil
+}
+
+type memberName struct {
+	// name is the unescaped name.
+	name []byte
+	// before and after are byte offsets into Decoder.buf that represents
+	// the entire name/value pair. It may contain leading commas.
+	before, after int64
+}
+
+var memberNamePool = sync.Pool{New: func() any { return new([]memberName) }}
+
+func getMemberNames() *[]memberName {
+	ns := memberNamePool.Get().(*[]memberName)
+	*ns = (*ns)[:0]
+	return ns
+}
+func putMemberNames(ns *[]memberName) {
+	if cap(*ns) < 1<<10 {
+		clear(*ns) // avoid pinning name
+		memberNamePool.Put(ns)
+	}
+}
+
+// reorderObjects recursively reorders all object members in place
+// according to the ordering specified in RFC 8785, section 3.2.3.
+//
+// Pre-conditions:
+//   - The value is valid (i.e., no decoder errors should ever occur).
+//   - The value is compact (i.e., no whitespace is present).
+//   - Initial call is provided a Decoder reading from the start of v.
+//
+// Post-conditions:
+//   - Exactly one JSON value is read from the Decoder.
+//   - All fully-parsed JSON objects are reordered by directly moving
+//     the members in the value buffer.
+//
+// The runtime is approximately O(n·log(n)) + O(m·log(m)),
+// where n is len(v) and m is the total number of object members.
+func reorderObjects(d *Decoder, scratch *[]byte) {
+	switch tok, _ := d.ReadToken(); tok.Kind() {
+	case '{':
+		// Iterate and collect the name and offsets for every object member.
+		members := getMemberNames()
+		defer putMemberNames(members)
+		var prevName []byte
+		isSorted := true
+
+		beforeBody := d.InputOffset() // offset after '{'
+		for d.PeekKind() != '}' {
+			beforeName := d.InputOffset()
+			var flags jsonwire.ValueFlags
+			name, _ := d.s.ReadValue(&flags)
+			name = jsonwire.UnquoteMayCopy(name, flags.IsVerbatim())
+			reorderObjects(d, scratch)
+			afterValue := d.InputOffset()
+
+			if isSorted && len(*members) > 0 {
+				isSorted = jsonwire.CompareUTF16(prevName, []byte(name)) < 0
+			}
+			*members = append(*members, memberName{name, beforeName, afterValue})
+			prevName = name
+		}
+		afterBody := d.InputOffset() // offset before '}'
+		d.ReadToken()
+
+		// Sort the members; return early if it's already sorted.
+		if isSorted {
+			return
+		}
+		slices.SortFunc(*members, func(x, y memberName) int {
+			return jsonwire.CompareUTF16(x.name, y.name)
+		})
+
+		// Append the reordered members to a new buffer,
+		// then copy the reordered members back over the original members.
+		// Avoid swapping in place since each member may be a different size
+		// where moving a member over a smaller member may corrupt the data
+		// for subsequent members before they have been moved.
+		//
+		// The following invariant must hold:
+		//	sum([m.after-m.before for m in members]) == afterBody-beforeBody
+		sorted := (*scratch)[:0]
+		for i, member := range *members {
+			if d.s.buf[member.before] == ',' {
+				member.before++ // trim leading comma
+			}
+			sorted = append(sorted, d.s.buf[member.before:member.after]...)
+			if i < len(*members)-1 {
+				sorted = append(sorted, ',') // append trailing comma
+			}
+		}
+		if int(afterBody-beforeBody) != len(sorted) {
+			panic("BUG: length invariant violated")
+		}
+		copy(d.s.buf[beforeBody:afterBody], sorted)
+
+		// Update scratch buffer to the largest amount ever used.
+		if len(sorted) > len(*scratch) {
+			*scratch = sorted
+		}
+	case '[':
+		for d.PeekKind() != ']' {
+			reorderObjects(d, scratch)
+		}
+		d.ReadToken()
+	}
+}

vendor/github.com/go-json-experiment/json/options.go

@@ -0,0 +1,273 @@
+// 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.
+
+package json
+
+import (
+	"fmt"
+
+	"github.com/go-json-experiment/json/internal"
+	"github.com/go-json-experiment/json/internal/jsonflags"
+	"github.com/go-json-experiment/json/internal/jsonopts"
+)
+
+// Options configure [Marshal], [MarshalWrite], [MarshalEncode],
+// [Unmarshal], [UnmarshalRead], and [UnmarshalDecode] with specific features.
+// Each function takes in a variadic list of options, where properties
+// set in later options override the value of previously set properties.
+//
+// The Options type is identical to [encoding/json.Options] and
+// [encoding/json/jsontext.Options]. Options from the other packages can
+// be used interchangeably with functionality in this package.
+//
+// Options represent either a singular option or a set of options.
+// It can be functionally thought of as a Go map of option properties
+// (even though the underlying implementation avoids Go maps for performance).
+//
+// The constructors (e.g., [Deterministic]) return a singular option value:
+//
+//	opt := Deterministic(true)
+//
+// which is analogous to creating a single entry map:
+//
+//	opt := Options{"Deterministic": true}
+//
+// [JoinOptions] composes multiple options values to together:
+//
+//	out := JoinOptions(opts...)
+//
+// which is analogous to making a new map and copying the options over:
+//
+//	out := make(Options)
+//	for _, m := range opts {
+//		for k, v := range m {
+//			out[k] = v
+//		}
+//	}
+//
+// [GetOption] looks up the value of options parameter:
+//
+//	v, ok := GetOption(opts, Deterministic)
+//
+// which is analogous to a Go map lookup:
+//
+//	v, ok := Options["Deterministic"]
+//
+// There is a single Options type, which is used with both marshal and unmarshal.
+// Some options affect both operations, while others only affect one operation:
+//
+//   - [StringifyNumbers] affects marshaling and unmarshaling
+//   - [Deterministic] affects marshaling only
+//   - [FormatNilSliceAsNull] affects marshaling only
+//   - [FormatNilMapAsNull] affects marshaling only
+//   - [MatchCaseInsensitiveNames] affects marshaling and unmarshaling
+//   - [DiscardUnknownMembers] affects marshaling only
+//   - [RejectUnknownMembers] affects unmarshaling only
+//   - [WithMarshalers] affects marshaling only
+//   - [WithUnmarshalers] affects unmarshaling only
+//
+// Options that do not affect a particular operation are ignored.
+type Options = jsonopts.Options
+
+// JoinOptions coalesces the provided list of options into a single Options.
+// Properties set in later options override the value of previously set properties.
+func JoinOptions(srcs ...Options) Options {
+	var dst jsonopts.Struct
+	for _, src := range srcs {
+		dst.Join(src)
+	}
+	return &dst
+}
+
+// GetOption returns the value stored in opts with the provided setter,
+// reporting whether the value is present.
+//
+// Example usage:
+//
+//	v, ok := json.GetOption(opts, json.Deterministic)
+//
+// Options are most commonly introspected to alter the JSON representation of
+// [MarshalerV2.MarshalJSONV2] and [MarshalerV2.MarshalJSONV2] methods, and
+// [MarshalFuncV2] and [UnmarshalFuncV2] functions.
+// In such cases, the presence bit should generally be ignored.
+func GetOption[T any](opts Options, setter func(T) Options) (T, bool) {
+	return jsonopts.GetOption(opts, setter)
+}
+
+// DefaultOptionsV2 is the full set of all options that define v2 semantics.
+// It is equivalent to all boolean options under [Options],
+// [encoding/json.Options], and [encoding/json/jsontext.Options]
+// being set to false. All non-boolean options are set to the zero value,
+// except for [jsontext.WithIndent], which defaults to "\t".
+func DefaultOptionsV2() Options {
+	return &jsonopts.DefaultOptionsV2
+}
+
+// StringifyNumbers specifies that numeric Go types should be marshaled
+// as a JSON string containing the equivalent JSON number value.
+// When unmarshaling, numeric Go types can be parsed from either
+// a JSON number or a JSON string containing the JSON number
+// without any surrounding whitespace.
+//
+// According to RFC 8259, section 6, a JSON implementation may choose to
+// limit the representation of a JSON number to an IEEE 754 binary64 value.
+// This may cause decoders to lose precision for int64 and uint64 types.
+// Quoting JSON numbers as a JSON string preserves the exact precision.
+//
+// This affects either marshaling or unmarshaling.
+func StringifyNumbers(v bool) Options {
+	if v {
+		return jsonflags.StringifyNumbers | 1
+	} else {
+		return jsonflags.StringifyNumbers | 0
+	}
+}
+
+// Deterministic specifies that the same input value will be serialized
+// as the exact same output bytes. Different processes of
+// the same program will serialize equal values to the same bytes,
+// but different versions of the same program are not guaranteed
+// to produce the exact same sequence of bytes.
+//
+// This only affects marshaling and is ignored when unmarshaling.
+func Deterministic(v bool) Options {
+	if v {
+		return jsonflags.Deterministic | 1
+	} else {
+		return jsonflags.Deterministic | 0
+	}
+}
+
+// FormatNilSliceAsNull specifies that a nil Go slice should marshal as a
+// JSON null instead of the default representation as an empty JSON array
+// (or an empty JSON string in the case of ~[]byte).
+// Slice fields explicitly marked with `format:emitempty` still marshal
+// as an empty JSON array.
+//
+// This only affects marshaling and is ignored when unmarshaling.
+func FormatNilSliceAsNull(v bool) Options {
+	if v {
+		return jsonflags.FormatNilSliceAsNull | 1
+	} else {
+		return jsonflags.FormatNilSliceAsNull | 0
+	}
+}
+
+// FormatNilMapAsNull specifies that a nil Go map should marshal as a
+// JSON null instead of the default representation as an empty JSON object.
+// Map fields explicitly marked with `format:emitempty` still marshal
+// as an empty JSON object.
+//
+// This only affects marshaling and is ignored when unmarshaling.
+func FormatNilMapAsNull(v bool) Options {
+	if v {
+		return jsonflags.FormatNilMapAsNull | 1
+	} else {
+		return jsonflags.FormatNilMapAsNull | 0
+	}
+}
+
+// MatchCaseInsensitiveNames specifies that JSON object members are matched
+// against Go struct fields using a case-insensitive match of the name.
+// Go struct fields explicitly marked with `strictcase` or `nocase`
+// always use case-sensitive (or case-insensitive) name matching,
+// regardless of the value of this option.
+//
+// This affects either marshaling or unmarshaling.
+// For marshaling, this option may alter the detection of duplicate names
+// (assuming [jsontext.AllowDuplicateNames] is false) from inlined fields
+// if it matches one of the declared fields in the Go struct.
+func MatchCaseInsensitiveNames(v bool) Options {
+	if v {
+		return jsonflags.MatchCaseInsensitiveNames | 1
+	} else {
+		return jsonflags.MatchCaseInsensitiveNames | 0
+	}
+}
+
+// DiscardUnknownMembers specifies that marshaling should ignore any
+// JSON object members stored in Go struct fields dedicated to storing
+// unknown JSON object members.
+//
+// This only affects marshaling and is ignored when unmarshaling.
+func DiscardUnknownMembers(v bool) Options {
+	if v {
+		return jsonflags.DiscardUnknownMembers | 1
+	} else {
+		return jsonflags.DiscardUnknownMembers | 0
+	}
+}
+
+// RejectUnknownMembers specifies that unknown members should be rejected
+// when unmarshaling a JSON object, regardless of whether there is a field
+// to store unknown members.
+//
+// This only affects unmarshaling and is ignored when marshaling.
+func RejectUnknownMembers(v bool) Options {
+	if v {
+		return jsonflags.RejectUnknownMembers | 1
+	} else {
+		return jsonflags.RejectUnknownMembers | 0
+	}
+}
+
+// WithMarshalers specifies a list of type-specific marshalers to use,
+// which can be used to override the default marshal behavior for values
+// of particular types.
+//
+// This only affects marshaling and is ignored when unmarshaling.
+func WithMarshalers(v *Marshalers) Options {
+	return (*marshalersOption)(v)
+}
+
+// WithUnmarshalers specifies a list of type-specific unmarshalers to use,
+// which can be used to override the default unmarshal behavior for values
+// of particular types.
+//
+// This only affects unmarshaling and is ignored when marshaling.
+func WithUnmarshalers(v *Unmarshalers) Options {
+	return (*unmarshalersOption)(v)
+}
+
+// These option types are declared here instead of "jsonopts"
+// to avoid a dependency on "reflect" from "jsonopts".
+type (
+	marshalersOption   Marshalers
+	unmarshalersOption Unmarshalers
+)
+
+func (*marshalersOption) JSONOptions(internal.NotForPublicUse)   {}
+func (*unmarshalersOption) JSONOptions(internal.NotForPublicUse) {}
+
+// Inject support into "jsonopts" to handle these types.
+func init() {
+	jsonopts.GetUnknownOption = func(src *jsonopts.Struct, zero jsonopts.Options) (any, bool) {
+		switch zero.(type) {
+		case *marshalersOption:
+			if !src.Flags.Has(jsonflags.Marshalers) {
+				return (*Marshalers)(nil), false
+			}
+			return src.Marshalers.(*Marshalers), true
+		case *unmarshalersOption:
+			if !src.Flags.Has(jsonflags.Unmarshalers) {
+				return (*Unmarshalers)(nil), false
+			}
+			return src.Unmarshalers.(*Unmarshalers), true
+		default:
+			panic(fmt.Sprintf("unknown option %T", zero))
+		}
+	}
+	jsonopts.JoinUnknownOption = func(dst *jsonopts.Struct, src jsonopts.Options) {
+		switch src := src.(type) {
+		case *marshalersOption:
+			dst.Flags.Set(jsonflags.Marshalers | 1)
+			dst.Marshalers = (*Marshalers)(src)
+		case *unmarshalersOption:
+			dst.Flags.Set(jsonflags.Unmarshalers | 1)
+			dst.Unmarshalers = (*Unmarshalers)(src)
+		default:
+			panic(fmt.Sprintf("unknown option %T", src))
+		}
+	}
+}