Merge branch 'goccy:master' into master

2024-06-24 23:46:58 +02:00 · 2024-06-24 23:46:58 +02:00 · 3aaec8ddc2
parent b43a13ce79 5e2ae3f23c
commit 3aaec8ddc2
21 changed files with 153 additions and 69 deletions
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@ -13,12 +13,13 @@ jobs:
      uses: actions/checkout@v3
    - name: build
      run: docker-compose run go-json
+
  test:
    name: Test
    strategy:
      matrix:
        os: [ "ubuntu-latest", "macos-latest", "windows-latest" ]
-        go-version: [ "1.18", "1.19", "1.20" ]
+        go-version: [ "1.19", "1.20", "1.21" ]
    runs-on: ${{ matrix.os }}
    steps:
    - name: setup Go ${{ matrix.go-version }}
@ -35,6 +36,20 @@ jobs:
        GOGC: 1
    - name: test with race detector
      run: go test -v -race ./... -count=1
+
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: checkout
+        uses: actions/checkout@v3
+      - name: setup Go
+        uses: actions/setup-go@v3
+        with:
+          go-version: '1.21'
+      - name: lint
+        run: |
+          make lint
  bench:
    name: Benchmark
    runs-on: ubuntu-latest
@ -42,7 +57,7 @@ jobs:
      - name: setup Go
        uses: actions/setup-go@v3
        with:
-          go-version: '1.20'
+          go-version: '1.21'
      - name: checkout ( feature )
        uses: actions/checkout@v3
      - name: run benchmark ( feature )
@ -57,19 +72,21 @@ jobs:
        run: cd benchmarks && go test -bench GoJson | tee $HOME/old.txt
      - name: compare benchmark results
        run: benchstat $HOME/old.txt $HOME/new.txt
+
  coverage:
    name: Coverage
    runs-on: ubuntu-latest
    steps:
+      - name: checkout
+        uses: actions/checkout@v3
      - name: setup Go
        uses: actions/setup-go@v3
        with:
-          go-version: '1.20'
-      - name: checkout
-        uses: actions/checkout@v3
+          go-version: '1.21'
      - name: measure coverage
        run: make cover
-      - uses: codecov/codecov-action@v3
+      - uses: codecov/codecov-action@v4
        with:
          fail_ci_if_error: true
          verbose: true
+          token: ${{ secrets.CODECOV_TOKEN }}
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@ -1,16 +0,0 @@
-name: lint
-on:
-  push:
-    branches:
-      - master
-  pull_request:
-jobs:
-  golangci:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - uses: golangci/golangci-lint-action@v3
-        with:
-          version: v1.45.2
-          args: --timeout=5m
--- a/.golangci.yml
+++ b/.golangci.yml
@ -56,6 +56,9 @@ linters:
    - cyclop
    - containedctx
    - revive
+    - nosnakecase
+    - exhaustruct
+    - depguard

 issues:
  exclude-rules:
--- a/2
+++ b/2
@ -30,7 +30,7 @@ golangci-lint: | $(BIN_DIR)
 		GOLANGCI_LINT_TMP_DIR=$$(mktemp -d); \
 		cd $$GOLANGCI_LINT_TMP_DIR; \
 		go mod init tmp; \
-		GOBIN=$(BIN_DIR) go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.48.0; \
+		GOBIN=$(BIN_DIR) go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.54.2; \
 		rm -rf $$GOLANGCI_LINT_TMP_DIR; \
 	}

--- a/benchmarks/bench_test.go
+++ b/benchmarks/bench_test.go
@ -15,7 +15,6 @@ import (
 	"compress/gzip"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"strings"
 	"testing"
@ -56,7 +55,7 @@ func codeInit() {
 	if err != nil {
 		panic(err)
 	}
-	data, err := ioutil.ReadAll(gz)
+	data, err := io.ReadAll(gz)
 	if err != nil {
 		panic(err)
 	}
@ -104,7 +103,7 @@ func Benchmark_EncodeBigData_GoJson(b *testing.B) {
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
-		enc := json.NewEncoder(ioutil.Discard)
+		enc := json.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&codeStruct); err != nil {
 				b.Fatal("Encode:", err)
@ -122,7 +121,7 @@ func Benchmark_EncodeBigData_EncodingJson(b *testing.B) {
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
-		enc := stdjson.NewEncoder(ioutil.Discard)
+		enc := stdjson.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&codeStruct); err != nil {
 				b.Fatal("Encode:", err)
@ -141,7 +140,7 @@ func Benchmark_EncodeBigData_JsonIter(b *testing.B) {
 	}
 	var json = jsoniter.ConfigCompatibleWithStandardLibrary
 	b.RunParallel(func(pb *testing.PB) {
-		enc := json.NewEncoder(ioutil.Discard)
+		enc := json.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&codeStruct); err != nil {
 				b.Fatal("Encode:", err)
@ -159,7 +158,7 @@ func Benchmark_EncodeBigData_SegmentioJson(b *testing.B) {
 		b.StartTimer()
 	}
 	b.RunParallel(func(pb *testing.PB) {
-		enc := segmentiojson.NewEncoder(ioutil.Discard)
+		enc := segmentiojson.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&codeStruct); err != nil {
 				b.Fatal("Encode:", err)
@ -316,7 +315,7 @@ func Benchmark_EncodeRawMessage_EncodingJson(b *testing.B) {
 	}{}

 	b.RunParallel(func(pb *testing.PB) {
-		enc := stdjson.NewEncoder(ioutil.Discard)
+		enc := stdjson.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&m); err != nil {
 				b.Fatal("Encode:", err)
@ -336,7 +335,7 @@ func Benchmark_EncodeRawMessage_JsonIter(b *testing.B) {
 	var json = jsoniter.ConfigCompatibleWithStandardLibrary

 	b.RunParallel(func(pb *testing.PB) {
-		enc := json.NewEncoder(ioutil.Discard)
+		enc := json.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&m); err != nil {
 				b.Fatal("Encode:", err)
@ -353,7 +352,7 @@ func Benchmark_EncodeRawMessage_GoJson(b *testing.B) {
 		B json.RawMessage
 	}{}
 	b.RunParallel(func(pb *testing.PB) {
-		enc := json.NewEncoder(ioutil.Discard)
+		enc := json.NewEncoder(io.Discard)
 		for pb.Next() {
 			if err := enc.Encode(&m); err != nil {
 				b.Fatal("Encode:", err)
--- a/benchmarks/go.mod
+++ b/benchmarks/go.mod
@ -1,6 +1,6 @@
 module benchmark

-go 1.12
+go 1.19

 require (
 	github.com/francoispqt/gojay v1.2.13
@ -9,9 +9,14 @@ require (
 	github.com/mailru/easyjson v0.0.0-20190312143242-1de009706dbe
 	github.com/pquerna/ffjson v0.0.0-20190930134022-aa0246cd15f7
 	github.com/segmentio/encoding v0.2.4
-	github.com/stretchr/testify v1.7.0 // indirect
 	github.com/valyala/fastjson v1.6.3
 	github.com/wI2L/jettison v0.7.1
 )

+require (
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.1 // indirect
+	github.com/stretchr/testify v1.7.0 // indirect
+)
+
 replace github.com/goccy/go-json => ../
--- a/benchmarks/go.sum
+++ b/benchmarks/go.sum
@ -56,7 +56,6 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/pty v1.1.3/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
-github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/lunixbochs/vtclean v1.0.0/go.mod h1:pHhQNgMf3btfWnGBVipUOjRYhoOsdGqdm/+2c2E2WMI=
 github.com/mailru/easyjson v0.0.0-20190312143242-1de009706dbe h1:W/GaMY0y69G4cFlmsC6B9sbuo2fP8OFP1ABjt4kPz+w=
@ -71,7 +70,6 @@ github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/neelance/astrewrite v0.0.0-20160511093645-99348263ae86/go.mod h1:kHJEU3ofeGjhHklVoIGuVj85JJwZ6kWPaJwCIxgnFmo=
 github.com/neelance/sourcemap v0.0.0-20151028013722-8c68805598ab/go.mod h1:Qr6/a/Q4r9LP1IltGz7tA7iOK1WonHEYhu1HRBA7ZiM=
-github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWbfPhv4DMiApHyliiK5xCTNVSPiaAs=
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
 github.com/openzipkin/zipkin-go v0.1.1/go.mod h1:NtoC/o8u3JlF1lSlyPNswIbeQH9bJTmOf0Erfk+hxe8=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
@ -182,7 +180,6 @@ google.golang.org/grpc v1.16.0/go.mod h1:0JHn/cJsOMiMfNA9+DeHDlAU7KAAB5GDlYFpa9M
 google.golang.org/grpc v1.17.0/go.mod h1:6QZJwpn2B+Zp71q/5VxRsJ6NXXVCE5NRUHRo+f3cWCs=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f h1:BLraFXnmrev5lT+xlilqcH8XK9/i0At2xKjWk4p6zsU=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/inf.v0 v0.9.1/go.mod h1:cWUDdTG/fYaXco+Dcufb5Vnc6Gp2YChqWtbxRZE0mXw=
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
--- a/decode_test.go
+++ b/decode_test.go
@ -197,6 +197,13 @@ func Test_Decoder(t *testing.T) {
 			assertEq(t, "interface{}", v.F, nil)
 			assertEq(t, "nilfunc", true, v.G == nil)
 		})
+		t.Run("struct.pointer must be nil", func(t *testing.T) {
+			var v struct {
+				A *int
+			}
+			json.Unmarshal([]byte(`{"a": "alpha"}`), &v)
+			assertEq(t, "struct.A", v.A, (*int)(nil))
+		})
 	})
 	t.Run("interface", func(t *testing.T) {
 		t.Run("number", func(t *testing.T) {
--- a/encode.go
+++ b/encode.go
@ -52,7 +52,7 @@ func (e *Encoder) EncodeContext(ctx context.Context, v interface{}, optFuncs ...
 	rctx.Option.Flag |= encoder.ContextOption
 	rctx.Option.Context = ctx

-	err := e.encodeWithOption(rctx, v, optFuncs...)
+	err := e.encodeWithOption(rctx, v, optFuncs...) //nolint: contextcheck

 	encoder.ReleaseRuntimeContext(rctx)
 	return err
@ -120,7 +120,7 @@ func marshalContext(ctx context.Context, v interface{}, optFuncs ...EncodeOption
 		optFunc(rctx.Option)
 	}

-	buf, err := encode(rctx, v)
+	buf, err := encode(rctx, v) //nolint: contextcheck
 	if err != nil {
 		encoder.ReleaseRuntimeContext(rctx)
 		return nil, err
--- a/go.mod
+++ b/go.mod
@ -1,3 +1,3 @@
 module github.com/goccy/go-json

-go 1.12
+go 1.19
--- a/internal/cmd/generator/main.go
+++ b/internal/cmd/generator/main.go
@ -7,7 +7,7 @@ import (
 	"go/parser"
 	"go/printer"
 	"go/token"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"runtime"
 	"strings"
@ -273,11 +273,11 @@ func (t OpType) FieldToOmitEmptyField() OpType {
 	if err != nil {
 		return err
 	}
-	return ioutil.WriteFile(path, buf, 0644)
+	return os.WriteFile(path, buf, 0644)
 }

 func generateVM() error {
-	file, err := ioutil.ReadFile("vm.go.tmpl")
+	file, err := os.ReadFile("vm.go.tmpl")
 	if err != nil {
 		return err
 	}
@ -295,7 +295,7 @@ func generateVM() error {
 		if err != nil {
 			return err
 		}
-		if err := ioutil.WriteFile(path, source, 0644); err != nil {
+		if err := os.WriteFile(path, source, 0644); err != nil {
 			return err
 		}
 	}
--- a/internal/decoder/ptr.go
+++ b/internal/decoder/ptr.go
@ -85,6 +85,7 @@ func (d *ptrDecoder) Decode(ctx *RuntimeContext, cursor, depth int64, p unsafe.P
 	}
 	c, err := d.dec.Decode(ctx, cursor, depth, newptr)
 	if err != nil {
+		*(*unsafe.Pointer)(p) = nil
 		return 0, err
 	}
 	cursor = c
--- a/internal/decoder/unmarshal_text.go
+++ b/internal/decoder/unmarshal_text.go
@ -147,7 +147,7 @@ func (d *unmarshalTextDecoder) DecodePath(ctx *RuntimeContext, cursor, depth int
 	return nil, 0, fmt.Errorf("json: unmarshal text decoder does not support decode path")
 }

-func unquoteBytes(s []byte) (t []byte, ok bool) {
+func unquoteBytes(s []byte) (t []byte, ok bool) { //nolint: nonamedreturns
 	length := len(s)
 	if length < 2 || s[0] != '"' || s[length-1] != '"' {
 		return
--- a/internal/encoder/compact.go
+++ b/internal/encoder/compact.go
@ -213,8 +213,8 @@ func compactString(dst, src []byte, cursor int64, escape bool) ([]byte, int64, e
 				dst = append(dst, src[start:cursor]...)
 				dst = append(dst, `\u202`...)
 				dst = append(dst, hex[src[cursor+2]&0xF])
-				cursor += 2
 				start = cursor + 3
+				cursor += 2
 			}
 		}
 		switch c {
--- a/internal/encoder/compiler.go
+++ b/internal/encoder/compiler.go
@ -480,7 +480,7 @@ func (c *Compiler) mapCode(typ *runtime.Type) (*MapCode, error) {

 func (c *Compiler) listElemCode(typ *runtime.Type) (Code, error) {
 	switch {
-	case c.isPtrMarshalJSONType(typ):
+	case c.implementsMarshalJSONType(typ) || c.implementsMarshalJSONType(runtime.PtrTo(typ)):
 		return c.marshalJSONCode(typ)
 	case !typ.Implements(marshalTextType) && runtime.PtrTo(typ).Implements(marshalTextType):
 		return c.marshalTextCode(typ)
--- a/internal/encoder/int.go
+++ b/internal/encoder/int.go
@ -1,3 +1,27 @@
+// This files's processing codes are inspired by https://github.com/segmentio/encoding.
+// The license notation is as follows.
+//
+// # MIT License
+//
+// Copyright (c) 2019 Segment.io, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
 package encoder

 import (
--- a/internal/encoder/string.go
+++ b/internal/encoder/string.go
@ -1,3 +1,27 @@
+// This files's string processing codes are inspired by https://github.com/segmentio/encoding.
+// The license notation is as follows.
+//
+// # MIT License
+//
+// Copyright (c) 2019 Segment.io, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
 package encoder

 import (
--- a/internal/runtime/rtype.go
+++ b/internal/runtime/rtype.go
@ -252,7 +252,6 @@ func IfaceIndir(*Type) bool
 //go:noescape
 func RType2Type(t *Type) reflect.Type

-//go:nolint structcheck
 type emptyInterface struct {
 	_   *Type
 	ptr unsafe.Pointer
--- a/json.go
+++ b/json.go
@ -89,31 +89,31 @@ type UnmarshalerContext interface {
 //
 // Examples of struct field tags and their meanings:
 //
-//   // Field appears in JSON as key "myName".
-//   Field int `json:"myName"`
+//	// Field appears in JSON as key "myName".
+//	Field int `json:"myName"`
 //
-//   // Field appears in JSON as key "myName" and
-//   // the field is omitted from the object if its value is empty,
-//   // as defined above.
-//   Field int `json:"myName,omitempty"`
+//	// Field appears in JSON as key "myName" and
+//	// the field is omitted from the object if its value is empty,
+//	// as defined above.
+//	Field int `json:"myName,omitempty"`
 //
-//   // Field appears in JSON as key "Field" (the default), but
-//   // the field is skipped if empty.
-//   // Note the leading comma.
-//   Field int `json:",omitempty"`
+//	// Field appears in JSON as key "Field" (the default), but
+//	// the field is skipped if empty.
+//	// Note the leading comma.
+//	Field int `json:",omitempty"`
 //
-//   // Field is ignored by this package.
-//   Field int `json:"-"`
+//	// Field is ignored by this package.
+//	Field int `json:"-"`
 //
-//   // Field appears in JSON as key "-".
-//   Field int `json:"-,"`
+//	// Field appears in JSON as key "-".
+//	Field int `json:"-,"`
 //
 // The "string" option signals that a field is stored as JSON inside a
 // JSON-encoded string. It applies only to fields of string, floating point,
 // integer, or boolean types. This extra level of encoding is sometimes used
 // when communicating with JavaScript programs:
 //
-//    Int64String int64 `json:",string"`
+//	Int64String int64 `json:",string"`
 //
 // The key name will be used if it's a non-empty string consisting of
 // only Unicode letters, digits, and ASCII punctuation except quotation
@ -166,7 +166,6 @@ type UnmarshalerContext interface {
 // JSON cannot represent cyclic data structures and Marshal does not
 // handle them. Passing cyclic structures to Marshal will result in
 // an infinite recursion.
-//
 func Marshal(v interface{}) ([]byte, error) {
 	return MarshalWithOption(v)
 }
@ -264,14 +263,13 @@ func MarshalIndentWithOption(v interface{}, prefix, indent string, optFuncs ...E
 //
 // The JSON null value unmarshals into an interface, map, pointer, or slice
 // by setting that Go value to nil. Because null is often used in JSON to mean
-// ``not present,'' unmarshaling a JSON null into any other Go type has no effect
+// “not present,” unmarshaling a JSON null into any other Go type has no effect
 // on the value and produces no error.
 //
 // When unmarshaling quoted strings, invalid UTF-8 or
 // invalid UTF-16 surrogate pairs are not treated as an error.
 // Instead, they are replaced by the Unicode replacement
 // character U+FFFD.
-//
 func Unmarshal(data []byte, v interface{}) error {
 	return unmarshal(data, v)
 }
@ -299,7 +297,6 @@ func UnmarshalNoEscape(data []byte, v interface{}, optFuncs ...DecodeOptionFunc)
 //	Number, for JSON numbers
 //	string, for JSON string literals
 //	nil, for JSON null
-//
 type Token = json.Token

 // A Number represents a JSON number literal.
--- a/stream_test.go
+++ b/stream_test.go
@ -9,7 +9,6 @@ import (
 	"compress/gzip"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
@ -234,7 +233,7 @@ func TestDecoderBuffered(t *testing.T) {
 	if m.Name != "Gopher" {
 		t.Errorf("Name = %q; want Gopher", m.Name)
 	}
-	rest, err := ioutil.ReadAll(d.Buffered())
+	rest, err := io.ReadAll(d.Buffered())
 	if err != nil {
 		t.Fatal(err)
 	}
--- a/test/cover/cover_slice_test.go
+++ b/test/cover/cover_slice_test.go
@ -16,6 +16,18 @@ func (coverSliceMarshalJSON) MarshalJSON() ([]byte, error) {
 	return []byte(`"hello"`), nil
 }

+type coverSliceMarshalJSONMap map[string]any
+
+func (c coverSliceMarshalJSONMap) MarshalJSON() ([]byte, error) {
+	return json.Marshal(map[string]any(c))
+}
+
+type coverSliceMarshalJSONMapPtr map[string]any
+
+func (c *coverSliceMarshalJSONMapPtr) MarshalJSON() ([]byte, error) {
+	return json.Marshal(map[string]any(*c))
+}
+
 type coverSliceMarshalText struct {
 	A int
 }
@ -152,6 +164,22 @@ func TestCoverSlice(t *testing.T) {
 			name: "SliceMarshalJSON",
 			data: []coverSliceMarshalJSON{{A: 1}, {A: 2}},
 		},
+		{
+			name: "SliceMarshalJSONMap",
+			data: []coverSliceMarshalJSONMap{{"foo": "bar"}, {"some": 1}},
+		},
+		{
+			name: "SliceMarshalJSONMap",
+			data: []*coverSliceMarshalJSONMap{{"foo": "bar"}, {"some": 1}},
+		},
+		{
+			name: "SliceMarshalJSONMap",
+			data: []coverSliceMarshalJSONMapPtr{{"foo": "bar"}, {"some": 1}},
+		},
+		{
+			name: "SliceMarshalJSONMap",
+			data: []*coverSliceMarshalJSONMapPtr{{"foo": "bar"}, {"some": 1}},
+		},
 		{
 			name: "SliceMarshalText",
 			data: []coverSliceMarshalText{{A: 1}, {A: 2}},