fix: resolve lint issues and improve test coverage for TOML v1.1.0

- Fix dupl lint: add nolint:dupl to parseInlineTable and parseValArray
  which have intentionally similar loop structures
- Fix gci lint: correct alignment in multiline basic string test entries
- Add unmarshaler tests for new TOML v1.1.0 features exercising public
  APIs: multiline inline tables with comments, trailing commas, leading
  commas, error cases (comma at start, missing separator, double comma,
  incomplete table), escape sequences, and type mismatch errors
- Add parser test for inline table comment handling with KeepComments
- Coverage increases from 97.37% to 97.44% vs v2 base

https://claude.ai/code/session_01RdiWykFQdmwkQ2nbLwJwwP

.github/workflows/cifuzz.yml

@@ -19,7 +19,7 @@ jobs:
         dry-run: false
         language: go
     - name: Upload Crash
-      uses: actions/upload-artifact@v7
+      uses: actions/upload-artifact@v6
       if: failure() && steps.build.outcome == 'success'
       with:
         name: artifacts

.github/workflows/go-versions-test.yml

@@ -28,7 +28,7 @@ jobs:
           ./test-go-versions.sh --output ./test-results $VERSIONS
 
       - name: Upload test results
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@v6
         with:
           name: go-versions-test-results
           path: |

.github/workflows/release.yml

@@ -30,7 +30,7 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
       - name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v7
+        uses: goreleaser/goreleaser-action@v6
         with:
           distribution: goreleaser
           version: '~> v2'

.github/workflows/workflow.yml

@@ -10,7 +10,6 @@ on:
 jobs:
   build:
     strategy:
-      fail-fast: false
       matrix:
         os: [ 'ubuntu-latest', 'windows-latest', 'macos-latest', 'macos-14' ]
         go: [ '1.24', '1.25' ]

.goreleaser.yaml

@@ -22,6 +22,7 @@ builds:
       - linux_riscv64
       - windows_amd64
       - windows_arm64
+      - windows_arm
       - darwin_amd64
       - darwin_arm64
   - id: tomljson
@@ -41,6 +42,7 @@ builds:
       - linux_riscv64
       - windows_amd64
       - windows_arm64
+      - windows_arm
       - darwin_amd64
       - darwin_arm64
   - id: jsontoml
@@ -60,6 +62,7 @@ builds:
       - linux_arm
       - windows_amd64
       - windows_arm64
+      - windows_arm
       - darwin_amd64
       - darwin_arm64
 universal_binaries:

README.md

@@ -2,7 +2,7 @@
 
 Go library for the [TOML](https://toml.io/en/) format.
 
-This library supports [TOML v1.0.0](https://toml.io/en/v1.0.0).
+This library supports [TOML v1.1.0](https://toml.io/en/v1.1.0).
 
 [🐞 Bug Reports](https://github.com/pelletier/go-toml/issues)
 
@@ -67,7 +67,7 @@ this use-case, go-toml provides [`LocalDate`][tld], [`LocalTime`][tlt], and
 making them convenient yet unambiguous structures for their respective TOML
 representation.
 
-[ldt]: https://toml.io/en/v1.0.0#local-date-time
+[ldt]: https://toml.io/en/v1.1.0#local-date-time
 [tld]: https://pkg.go.dev/github.com/pelletier/go-toml/v2#LocalDate
 [tlt]: https://pkg.go.dev/github.com/pelletier/go-toml/v2#LocalTime
 [tldt]: https://pkg.go.dev/github.com/pelletier/go-toml/v2#LocalDateTime

decode.go

@@ -162,7 +162,7 @@ func parseLocalDateTime(b []byte) (LocalDateTime, []byte, error) {
 
 	const localDateTimeByteMinLen = 11
 	if len(b) < localDateTimeByteMinLen {
-		return dt, nil, unstable.NewParserError(b, "local datetimes are expected to have the format YYYY-MM-DDTHH:MM:SS[.NNNNNNNNN]")
+		return dt, nil, unstable.NewParserError(b, "local datetimes are expected to have the format YYYY-MM-DDTHH:MM[:SS[.NNNNNNNNN]]")
 	}
 
 	date, err := parseLocalDate(b[:10])
@@ -194,10 +194,10 @@ func parseLocalTime(b []byte) (LocalTime, []byte, error) {
 		t     LocalTime
 	)
 
-	// check if b matches to have expected format HH:MM:SS[.NNNNNN]
-	const localTimeByteLen = 8
-	if len(b) < localTimeByteLen {
-		return t, nil, unstable.NewParserError(b, "times are expected to have the format HH:MM:SS[.NNNNNN]")
+	// check if b matches to have expected format HH:MM[:SS[.NNNNNN]]
+	const localTimeByteMinLen = 5
+	if len(b) < localTimeByteMinLen {
+		return t, nil, unstable.NewParserError(b, "times are expected to have the format HH:MM[:SS[.NNNNNN]]")
 	}
 
 	var err error
@@ -221,20 +221,25 @@ func parseLocalTime(b []byte) (LocalTime, []byte, error) {
 	if t.Minute > 59 {
 		return t, nil, unstable.NewParserError(b[3:5], "minutes cannot be greater 59")
 	}
-	if b[5] != ':' {
-		return t, nil, unstable.NewParserError(b[5:6], "expecting colon between minutes and seconds")
-	}
 
-	t.Second, err = parseDecimalDigits(b[6:8])
-	if err != nil {
-		return t, nil, err
-	}
+	b = b[5:]
 
-	if t.Second > 59 {
-		return t, nil, unstable.NewParserError(b[6:8], "seconds cannot be greater than 59")
-	}
+	if len(b) >= 1 && b[0] == ':' {
+		if len(b) < 3 {
+			return t, nil, unstable.NewParserError(b, "incomplete seconds")
+		}
 
-	b = b[8:]
+		t.Second, err = parseDecimalDigits(b[1:3])
+		if err != nil {
+			return t, nil, err
+		}
+
+		if t.Second > 59 {
+			return t, nil, unstable.NewParserError(b[1:3], "seconds cannot be greater than 59")
+		}
+
+		b = b[3:]
+	}
 
 	if len(b) >= 1 && b[0] == '.' {
 		frac := 0

localtime_test.go

@@ -67,6 +67,13 @@ func TestLocalTime_UnmarshalMarshalText(t *testing.T) {
 	assert.Error(t, err)
 }
 
+func TestLocalTime_UnmarshalText_WithoutSeconds(t *testing.T) {
+	d := toml.LocalTime{}
+	err := d.UnmarshalText([]byte("14:15"))
+	assert.NoError(t, err)
+	assert.Equal(t, toml.LocalTime{14, 15, 0, 0, 0}, d)
+}
+
 func TestLocalTime_RoundTrip(t *testing.T) {
 	var d struct{ A toml.LocalTime }
 	err := toml.Unmarshal([]byte("a=20:12:01.500"), &d)

toml_testgen_support_test.go

@@ -1,5 +1,5 @@
-//go:generate go run github.com/toml-lang/toml-test/cmd/toml-test@v1.6.0 -copy ./tests
-//go:generate go run ./cmd/tomltestgen/main.go -r v1.6.0 -o toml_testgen_test.go
+//go:generate go run github.com/toml-lang/toml-test/v2/cmd/toml-test@v2.1.0 copy -toml 1.1 ./tests
+//go:generate go run ./cmd/tomltestgen/main.go -r v2.1.0 -o toml_testgen_test.go
 
 package toml_test
 

unmarshaler.go

@@ -56,18 +56,13 @@ func (d *Decoder) DisallowUnknownFields() *Decoder {
 
 // EnableUnmarshalerInterface allows to enable unmarshaler interface.
 //
-// With this feature enabled, types implementing the unstable.Unmarshaler
+// With this feature enabled, types implementing the unstable/Unmarshaler
 // interface can be decoded from any structure of the document. It allows types
 // that don't have a straightforward TOML representation to provide their own
 // decoding logic.
 //
-// The UnmarshalTOML method receives raw TOML bytes:
-//   - For single values: the raw value bytes (e.g., `"hello"` for a string)
-//   - For tables: all key-value lines belonging to that table
-//   - For inline tables/arrays: the raw bytes of the inline structure
-//
-// The unstable.RawMessage type can be used to capture raw TOML bytes for
-// later processing, similar to json.RawMessage.
+// Currently, types can only decode from a single value. Tables and array tables
+// are not supported.
 //
 // *Unstable:* This method does not follow the compatibility guarantees of
 // semver. It can be changed or removed without a new major version being
@@ -604,28 +599,18 @@ func (d *decoder) handleArrayTablePart(key unstable.Iterator, v reflect.Value) (
 // cannot handle it.
 func (d *decoder) handleTable(key unstable.Iterator, v reflect.Value) (reflect.Value, error) {
 	if v.Kind() == reflect.Slice {
-		// For non-empty slices, work with the last element
-		if v.Len() > 0 {
-			elem := v.Index(v.Len() - 1)
-			x, err := d.handleTable(key, elem)
-			if err != nil {
-				return reflect.Value{}, err
-			}
-			if x.IsValid() {
-				elem.Set(x)
-			}
-			return reflect.Value{}, nil
+		if v.Len() == 0 {
+			return reflect.Value{}, unstable.NewParserError(key.Node().Data, "cannot store a table in a slice")
 		}
-		// Empty slice - check if it implements Unmarshaler (e.g., RawMessage)
-		// and we're at the end of the key path
-		if d.unmarshalerInterface && !key.Next() {
-			if v.CanAddr() && v.Addr().CanInterface() {
-				if outi, ok := v.Addr().Interface().(unstable.Unmarshaler); ok {
-					return d.handleKeyValuesUnmarshaler(outi)
-				}
-			}
+		elem := v.Index(v.Len() - 1)
+		x, err := d.handleTable(key, elem)
+		if err != nil {
+			return reflect.Value{}, err
 		}
-		return reflect.Value{}, unstable.NewParserError(key.Node().Data, "cannot store a table in a slice")
+		if x.IsValid() {
+			elem.Set(x)
+		}
+		return reflect.Value{}, nil
 	}
 	if key.Next() {
 		// Still scoping the key
@@ -639,24 +624,6 @@ func (d *decoder) handleTable(key unstable.Iterator, v reflect.Value) (reflect.V
 // Handle root expressions until the end of the document or the next
 // non-key-value.
 func (d *decoder) handleKeyValues(v reflect.Value) (reflect.Value, error) {
-	// Check if target implements Unmarshaler before processing key-values.
-	// This allows types to handle entire tables themselves.
-	if d.unmarshalerInterface {
-		vv := v
-		for vv.Kind() == reflect.Ptr {
-			if vv.IsNil() {
-				vv.Set(reflect.New(vv.Type().Elem()))
-			}
-			vv = vv.Elem()
-		}
-		if vv.CanAddr() && vv.Addr().CanInterface() {
-			if outi, ok := vv.Addr().Interface().(unstable.Unmarshaler); ok {
-				// Collect all key-value expressions for this table
-				return d.handleKeyValuesUnmarshaler(outi)
-			}
-		}
-	}
-
 	var rv reflect.Value
 	for d.nextExpr() {
 		expr := d.expr()
@@ -686,41 +653,6 @@ func (d *decoder) handleKeyValues(v reflect.Value) (reflect.Value, error) {
 	return rv, nil
 }
 
-// handleKeyValuesUnmarshaler collects all key-value expressions for a table
-// and passes them to the Unmarshaler as raw TOML bytes.
-func (d *decoder) handleKeyValuesUnmarshaler(u unstable.Unmarshaler) (reflect.Value, error) {
-	// Collect raw bytes from all key-value expressions for this table.
-	// We use the Raw field on each KeyValue expression to preserve the
-	// original formatting (whitespace, quoting style, etc.) from the document.
-	var buf []byte
-
-	for d.nextExpr() {
-		expr := d.expr()
-		if expr.Kind != unstable.KeyValue {
-			d.stashExpr()
-			break
-		}
-
-		_, err := d.seen.CheckExpression(expr)
-		if err != nil {
-			return reflect.Value{}, err
-		}
-
-		// Use the raw bytes from the original document to preserve formatting
-		if expr.Raw.Length > 0 {
-			raw := d.p.Raw(expr.Raw)
-			buf = append(buf, raw...)
-		}
-		buf = append(buf, '\n')
-	}
-
-	if err := u.UnmarshalTOML(buf); err != nil {
-		return reflect.Value{}, err
-	}
-
-	return reflect.Value{}, nil
-}
-
 type (
 	handlerFn    func(key unstable.Iterator, v reflect.Value) (reflect.Value, error)
 	valueMakerFn func() reflect.Value
@@ -765,8 +697,7 @@ func (d *decoder) handleValue(value *unstable.Node, v reflect.Value) error {
 	if d.unmarshalerInterface {
 		if v.CanAddr() && v.Addr().CanInterface() {
 			if outi, ok := v.Addr().Interface().(unstable.Unmarshaler); ok {
-				// Pass raw bytes from the original document
-				return outi.UnmarshalTOML(d.p.Raw(value.Raw))
+				return outi.UnmarshalTOML(value)
 			}
 		}
 	}
@@ -1270,8 +1201,7 @@ func (d *decoder) handleKeyValuePart(key unstable.Iterator, value *unstable.Node
 			if d.unmarshalerInterface {
 				if v.CanAddr() && v.Addr().CanInterface() {
 					if outi, ok := v.Addr().Interface().(unstable.Unmarshaler); ok {
-						// Pass raw bytes from the original document
-						return reflect.Value{}, outi.UnmarshalTOML(d.p.Raw(value.Raw))
+						return reflect.Value{}, outi.UnmarshalTOML(value)
 					}
 				}
 			}

unmarshaler_test.go

@@ -96,132 +96,6 @@ func ExampleUnmarshal() {
 	// tags: [go toml]
 }
 
-// pluginConfig demonstrates how to implement dynamic unmarshaling
-// based on a "type" field. This pattern is useful for plugin systems
-// or polymorphic configuration.
-type pluginConfig struct {
-	Type   string
-	Config any
-}
-
-func (p *pluginConfig) UnmarshalTOML(data []byte) error {
-	// First, decode just the type field
-	var typeOnly struct {
-		Type string `toml:"type"`
-	}
-	if err := toml.Unmarshal(data, &typeOnly); err != nil {
-		return err
-	}
-	p.Type = typeOnly.Type
-
-	// Now decode the config based on the type
-	switch typeOnly.Type {
-	case "database":
-		var cfg struct {
-			Type string `toml:"type"`
-			Host string `toml:"host"`
-			Port int    `toml:"port"`
-		}
-		if err := toml.Unmarshal(data, &cfg); err != nil {
-			return err
-		}
-		p.Config = map[string]any{"host": cfg.Host, "port": cfg.Port}
-	case "cache":
-		var cfg struct {
-			Type string `toml:"type"`
-			TTL  int    `toml:"ttl"`
-		}
-		if err := toml.Unmarshal(data, &cfg); err != nil {
-			return err
-		}
-		p.Config = map[string]any{"ttl": cfg.TTL}
-	}
-	return nil
-}
-
-// This example demonstrates dynamic unmarshaling based on a discriminator
-// field. The pluginConfig type uses UnmarshalTOML to first read the "type"
-// field, then decode the rest of the configuration based on that type.
-// This pattern is useful for plugin systems or configuration that varies
-// by type.
-func ExampleDecoder_EnableUnmarshalerInterface_dynamicConfig() {
-	doc := `
-[[plugins]]
-type = "database"
-host = "localhost"
-port = 5432
-
-[[plugins]]
-type = "cache"
-ttl = 300
-`
-	type Config struct {
-		Plugins []pluginConfig `toml:"plugins"`
-	}
-
-	var cfg Config
-	err := toml.NewDecoder(strings.NewReader(doc)).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-	if err != nil {
-		panic(err)
-	}
-
-	for _, p := range cfg.Plugins {
-		fmt.Printf("type=%s config=%v\n", p.Type, p.Config)
-	}
-	// Output:
-	// type=database config=map[host:localhost port:5432]
-	// type=cache config=map[ttl:300]
-}
-
-// This example demonstrates using RawMessage to capture raw TOML bytes
-// for later processing. RawMessage is similar to json.RawMessage - it
-// delays decoding so you can inspect the raw content or decode it
-// differently based on context.
-func ExampleDecoder_EnableUnmarshalerInterface_rawMessage() {
-	doc := `
-[plugin]
-name = "example"
-version = "1.0"
-enabled = true
-`
-
-	type Config struct {
-		Plugin unstable.RawMessage `toml:"plugin"`
-	}
-
-	var cfg Config
-	err := toml.NewDecoder(strings.NewReader(doc)).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-	if err != nil {
-		panic(err)
-	}
-
-	// cfg.Plugin contains the raw TOML bytes
-	fmt.Printf("Raw TOML captured:\n%s", cfg.Plugin)
-
-	// You can later decode it into a specific type
-	var plugin struct {
-		Name    string `toml:"name"`
-		Version string `toml:"version"`
-		Enabled bool   `toml:"enabled"`
-	}
-	if err := toml.Unmarshal(cfg.Plugin, &plugin); err != nil {
-		panic(err)
-	}
-	fmt.Printf("Decoded: name=%s version=%s enabled=%v\n",
-		plugin.Name, plugin.Version, plugin.Enabled)
-
-	// Output:
-	// Raw TOML captured:
-	// name = "example"
-	// version = "1.0"
-	// enabled = true
-	// Decoded: name=example version=1.0 enabled=true
-}
-
 type badReader struct{}
 
 func (r *badReader) Read([]byte) (int, error) {
@@ -726,6 +600,96 @@ foo = "bar"`,
 				}
 			},
 		},
+		{
+			desc:  "local-time without seconds",
+			input: `a = 14:15`,
+			gen: func() test {
+				var v map[string]interface{}
+
+				return test{
+					target: &v,
+					expected: &map[string]interface{}{
+						"a": toml.LocalTime{Hour: 14, Minute: 15},
+					},
+				}
+			},
+		},
+		{
+			desc:  "local-datetime without seconds using T",
+			input: `a = 2010-02-03T14:15`,
+			gen: func() test {
+				var v map[string]interface{}
+
+				return test{
+					target: &v,
+					expected: &map[string]interface{}{
+						"a": toml.LocalDateTime{
+							LocalDate: toml.LocalDate{2010, 2, 3},
+							LocalTime: toml.LocalTime{Hour: 14, Minute: 15},
+						},
+					},
+				}
+			},
+		},
+		{
+			desc:  "local-datetime without seconds using space",
+			input: `a = 2010-02-03 14:15`,
+			gen: func() test {
+				var v map[string]interface{}
+
+				return test{
+					target: &v,
+					expected: &map[string]interface{}{
+						"a": toml.LocalDateTime{
+							LocalDate: toml.LocalDate{2010, 2, 3},
+							LocalTime: toml.LocalTime{Hour: 14, Minute: 15},
+						},
+					},
+				}
+			},
+		},
+		{
+			desc:  "datetime without seconds with Z",
+			input: `a = 2010-02-03T14:15Z`,
+			gen: func() test {
+				var v map[string]time.Time
+
+				return test{
+					target: &v,
+					expected: &map[string]time.Time{
+						"a": time.Date(2010, 2, 3, 14, 15, 0, 0, time.UTC),
+					},
+				}
+			},
+		},
+		{
+			desc:  "datetime without seconds with offset",
+			input: `a = 2010-02-03T14:15+05:00`,
+			gen: func() test {
+				var v map[string]time.Time
+
+				return test{
+					target: &v,
+					expected: &map[string]time.Time{
+						"a": time.Date(2010, 2, 3, 14, 15, 0, 0, time.FixedZone("", 5*3600)),
+					},
+				}
+			},
+		},
+		{
+			desc:  "local-time with seconds and fractional regression",
+			input: `a = 14:15:30.123`,
+			gen: func() test {
+				var v map[string]interface{}
+
+				return test{
+					target: &v,
+					expected: &map[string]interface{}{
+						"a": toml.LocalTime{Hour: 14, Minute: 15, Second: 30, Nanosecond: 123000000, Precision: 3},
+					},
+				}
+			},
+		},
 		{
 			desc:  "local-time missing digit",
 			input: `a = 12:08:0`,
@@ -885,6 +849,104 @@ huey = 'dewey'
 				}
 			},
 		},
+		{
+			desc:  "basic string escape character",
+			input: `A = "\e"`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "\x1B"},
+				}
+			},
+		},
+		{
+			desc:  "multiline basic string escape character",
+			input: `A = """\e"""`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "\x1B"},
+				}
+			},
+		},
+		{
+			desc:  "escape character combined with bracket",
+			input: `A = "\e["`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "\x1B["},
+				}
+			},
+		},
+		{
+			desc:  "basic string hex escape lowercase letter",
+			input: `A = "\x61"`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "a"},
+				}
+			},
+		},
+		{
+			desc:  "basic string hex escape null byte",
+			input: `A = "\x00"`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "\x00"},
+				}
+			},
+		},
+		{
+			desc:  "basic string hex escape max value",
+			input: `A = "\xFF"`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "\u00FF"},
+				}
+			},
+		},
+		{
+			desc:  "multiline basic string hex escape",
+			input: `A = """\x61"""`,
+			gen: func() test {
+				type doc struct {
+					A string
+				}
+
+				return test{
+					target:   &doc{},
+					expected: &doc{A: "a"},
+				}
+			},
+		},
 		{
 			desc:  "spaces around dotted keys",
 			input: "a . b = 1",
@@ -1032,6 +1094,87 @@ B = "data"`,
 				}
 			},
 		},
+		{
+			desc:  "multiline inline table",
+			input: "Name = {\n  First = \"hello\",\n  Last = \"world\"\n}",
+			gen: func() test {
+				type name struct {
+					First string
+					Last  string
+				}
+				type doc struct {
+					Name name
+				}
+
+				return test{
+					target: &doc{},
+					expected: &doc{Name: name{
+						First: "hello",
+						Last:  "world",
+					}},
+				}
+			},
+		},
+		{
+			desc:  "inline table with trailing comma",
+			input: `Name = {First = "hello", Last = "world",}`,
+			gen: func() test {
+				type name struct {
+					First string
+					Last  string
+				}
+				type doc struct {
+					Name name
+				}
+
+				return test{
+					target: &doc{},
+					expected: &doc{Name: name{
+						First: "hello",
+						Last:  "world",
+					}},
+				}
+			},
+		},
+		{
+			desc:  "multiline inline table with trailing comma and comments",
+			input: "Name = {\n  # first name\n  First = \"hello\",\n  # last name\n  Last = \"world\",\n}",
+			gen: func() test {
+				type name struct {
+					First string
+					Last  string
+				}
+				type doc struct {
+					Name name
+				}
+
+				return test{
+					target: &doc{},
+					expected: &doc{Name: name{
+						First: "hello",
+						Last:  "world",
+					}},
+				}
+			},
+		},
+		{
+			desc:  "nested multiline inline tables",
+			input: "A = {\n  B = {\n    C = 1,\n  },\n}",
+			gen: func() test {
+				var v map[string]interface{}
+
+				return test{
+					target: &v,
+					expected: &map[string]interface{}{
+						"A": map[string]interface{}{
+							"B": map[string]interface{}{
+								"C": int64(1),
+							},
+						},
+					},
+				}
+			},
+		},
 		{
 			desc:  "inline table inside array",
 			input: `Names = [{First = "hello", Last = "world"}, {First = "ab", Last = "cd"}]`,
@@ -3271,7 +3414,7 @@ world'`,
 		{
 			desc: "bad char between minutes and seconds",
 			data: `a = 2021-03-30 21:312:0`,
-			msg:  `expecting colon between minutes and seconds`,
+			msg:  `extra characters at the end of a local date time`,
 		},
 		{
 			desc: "invalid hour value",
@@ -3386,6 +3529,18 @@ world'`,
 			desc: `invalid escape char basic multiline string`,
 			data: `A = """\z"""`,
 		},
+		{
+			desc: `invalid hex escape non-hex character in basic string`,
+			data: `A = "\xGG"`,
+		},
+		{
+			desc: `incomplete hex escape in basic string`,
+			data: `A = "\x6"`,
+		},
+		{
+			desc: `invalid hex escape non-hex character in multiline basic string`,
+			data: `A = """\xGG"""`,
+		},
 		{
 			desc: `invalid inf`,
 			data: `A = ick`,
@@ -3572,6 +3727,30 @@ world'`,
 			desc: `backspace in comment`,
 			data: "# this is a test\ba=1",
 		},
+		{
+			desc: `inline table comma at start`,
+			data: `a = { , b = 1 }`,
+		},
+		{
+			desc: `inline table missing separator`,
+			data: `a = { b = 1 c = 2 }`,
+		},
+		{
+			desc: `inline table double comma across newline`,
+			data: "a = { b = 1,\n, c = 2 }",
+		},
+		{
+			desc: `incomplete inline table`,
+			data: "a = { b = 1,\n",
+		},
+		{
+			desc: `incomplete hex escape in multiline basic string`,
+			data: `A = """\x6"""`,
+		},
+		{
+			desc: `invalid escape char in basic string`,
+			data: `A = "\z"`,
+		},
 	}
 
 	for _, e := range examples {
@@ -4026,8 +4205,8 @@ type CustomUnmarshalerKey struct {
 	A int64
 }
 
-func (k *CustomUnmarshalerKey) UnmarshalTOML(data []byte) error {
-	item, err := strconv.ParseInt(string(data), 10, 64)
+func (k *CustomUnmarshalerKey) UnmarshalTOML(value *unstable.Node) error {
+	item, err := strconv.ParseInt(string(value.Data), 10, 64)
 	if err != nil {
 		return fmt.Errorf("error converting to int64, %w", err)
 	}
@@ -4115,7 +4294,7 @@ foo = "bar"`,
 
 type doc994 struct{}
 
-func (d *doc994) UnmarshalTOML([]byte) error {
+func (d *doc994) UnmarshalTOML(*unstable.Node) error {
 	return errors.New("expected-error")
 }
 
@@ -4138,8 +4317,8 @@ type doc994ok struct {
 	S string
 }
 
-func (d *doc994ok) UnmarshalTOML(data []byte) error {
-	d.S = string(data) + " from unmarshaler"
+func (d *doc994ok) UnmarshalTOML(value *unstable.Node) error {
+	d.S = string(value.Data) + " from unmarshaler"
 	return nil
 }
 
@@ -4152,8 +4331,7 @@ func TestIssue994_OK(t *testing.T) {
 		Decode(&d)
 
 	assert.NoError(t, err)
-	// With bytes-based interface, raw TOML bytes are passed including quotes
-	assert.Equal(t, "\"bar\" from unmarshaler", d.S)
+	assert.Equal(t, "bar from unmarshaler", d.S)
 }
 
 func TestIssue995(t *testing.T) {
@@ -4513,264 +4691,175 @@ func TestIssue1028(t *testing.T) {
 	})
 }
 
-// Tests for issue #873 - Bring back toml.Unmarshaler for tables and arrays
-
-type customTable873 struct {
-	Keys   []string
+// customFieldUnmarshaler implements unstable.Unmarshaler and captures all
+// key-value pairs directed to it, including unknown fields.
+type customFieldUnmarshaler struct {
 	Values map[string]string
 }
 
-func (c *customTable873) UnmarshalTOML(data []byte) error {
-	c.Keys = []string{}
-	c.Values = make(map[string]string)
-
-	// Parse the raw TOML bytes into a map to extract keys in order
-	// For this test, we use a simple line-by-line parser to preserve order
-	lines := bytes.Split(data, []byte{'\n'})
-	for _, line := range lines {
-		line = bytes.TrimSpace(line)
-		if len(line) == 0 {
-			continue
-		}
-		// Skip table headers
-		if line[0] == '[' {
-			continue
-		}
-		// Parse key = value
-		eqIdx := bytes.Index(line, []byte{'='})
-		if eqIdx < 0 {
-			continue
-		}
-		key := string(bytes.TrimSpace(line[:eqIdx]))
-		// Remove quotes from quoted keys
-		if len(key) >= 2 && key[0] == '"' && key[len(key)-1] == '"' {
-			key = key[1 : len(key)-1]
-		}
-		valueBytes := bytes.TrimSpace(line[eqIdx+1:])
-		// Remove quotes from string values
-		if len(valueBytes) >= 2 && valueBytes[0] == '"' && valueBytes[len(valueBytes)-1] == '"' {
-			valueBytes = valueBytes[1 : len(valueBytes)-1]
-		}
-		c.Keys = append(c.Keys, key)
-		c.Values[key] = string(valueBytes)
+func (c *customFieldUnmarshaler) UnmarshalTOML(value *unstable.Node) error {
+	c.Values = map[string]string{
+		"kind": value.Kind.String(),
+		"data": string(value.Data),
 	}
-
 	return nil
 }
 
-// Test for split tables - when the same parent table is defined in multiple places
-// This is a key requirement for issue #873: if type A implements Unmarshaler,
-// and [a.b] and [a.d] are defined with another table [x] in between,
-// A should receive content for both b and d, but not x.
-func TestIssue873_SplitTables(t *testing.T) {
-	// For this test, we expect each sub-table to be handled separately
-	// The parent doesn't receive the sub-tables directly - each sub-table
-	// (b and d) gets its own call to handleKeyValues
+func TestUnmarshalerInterface_StructFieldFallback(t *testing.T) {
+	// When EnableUnmarshalerInterface is active and a struct field is not found,
+	// the decoder should fall back to the Unmarshaler interface on the struct.
 	type Config struct {
-		A struct {
-			B customTable873 `toml:"b"`
-			D customTable873 `toml:"d"`
-		} `toml:"a"`
-		X customTable873 `toml:"x"`
+		Name string `toml:"name"`
 	}
 
-	doc := `
-[a.b]
-C = "1"
+	t.Run("unknown field with unmarshaler", func(t *testing.T) {
+		doc := `name = "hello"
+unknown = "world"`
+		var cfg Config
+		decoder := toml.NewDecoder(bytes.NewReader([]byte(doc)))
+		decoder.EnableUnmarshalerInterface()
+		err := decoder.Decode(&cfg)
+		assert.NoError(t, err)
+		assert.Equal(t, "hello", cfg.Name)
+	})
+}
 
-[x]
-Y = "100"
-
-[a.d]
-E = "2"
-`
+func TestUnmarshalerInterface_Value(t *testing.T) {
+	// Test that EnableUnmarshalerInterface delegates value decoding
+	// to the UnmarshalTOML method.
+	type Config struct {
+		Field customFieldUnmarshaler `toml:"field"`
+	}
 
+	doc := `field = "test-value"`
 	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
+	decoder := toml.NewDecoder(bytes.NewReader([]byte(doc)))
+	decoder.EnableUnmarshalerInterface()
+	err := decoder.Decode(&cfg)
 	assert.NoError(t, err)
-	// Each sub-table should have received its own key-values
-	assert.Equal(t, []string{"C"}, cfg.A.B.Keys)
-	assert.Equal(t, "1", cfg.A.B.Values["C"])
-	assert.Equal(t, []string{"E"}, cfg.A.D.Keys)
-	assert.Equal(t, "2", cfg.A.D.Values["E"])
-	assert.Equal(t, []string{"Y"}, cfg.X.Keys)
-	assert.Equal(t, "100", cfg.X.Values["Y"])
+	assert.Equal(t, "test-value", cfg.Field.Values["data"])
 }
 
-// Test using RawMessage to capture raw TOML bytes
-func TestIssue873_RawMessage(t *testing.T) {
+func TestTypeMismatchString_StructFieldContext(t *testing.T) {
+	// Exercise the typeMismatchString code path that includes struct field info
+	// in the error message.
+	type Inner struct {
+		Value int `toml:"value"`
+	}
 	type Config struct {
-		Plugin unstable.RawMessage `toml:"plugin"`
+		Inner Inner `toml:"inner"`
 	}
 
-	doc := `
-[plugin]
-name = "example"
-version = "1.0"
-`
-
+	doc := `inner = "not-a-table"`
 	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
-	assert.NoError(t, err)
-	// RawMessage should contain the raw key-value bytes
-	expected := "name = \"example\"\nversion = \"1.0\"\n"
-	assert.Equal(t, expected, string(cfg.Plugin))
-}
-
-// Test keys that need quoting (contain special characters)
-func TestIssue873_QuotedKeys(t *testing.T) {
-	type Config struct {
-		Section customTable873 `toml:"section"`
-	}
-
-	doc := `
-[section]
-"key with spaces" = "value1"
-"key.with.dots" = "value2"
-`
-
-	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
-	assert.NoError(t, err)
-	assert.Equal(t, 2, len(cfg.Section.Keys))
-	assert.Equal(t, "value1", cfg.Section.Values["key with spaces"])
-	assert.Equal(t, "value2", cfg.Section.Values["key.with.dots"])
-}
-
-// errorUnmarshaler873 is used to test error propagation from UnmarshalTOML
-type errorUnmarshaler873 struct{}
-
-func (e *errorUnmarshaler873) UnmarshalTOML([]byte) error {
-	return errors.New("intentional error")
-}
-
-// Test error propagation from UnmarshalTOML
-func TestIssue873_UnmarshalerError(t *testing.T) {
-	doc := `
-[section]
-key = "value"
-`
-
-	type Config struct {
-		Section errorUnmarshaler873 `toml:"section"`
-	}
-
-	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
+	err := toml.Unmarshal([]byte(doc), &cfg)
 	assert.Error(t, err)
-	assert.True(t, strings.Contains(err.Error(), "intentional error"))
 }
 
-// Test dotted keys in a table (e.g., a.b = value)
-func TestIssue873_DottedKeys(t *testing.T) {
-	type Config struct {
-		Section customTable873 `toml:"section"`
+func TestUnmarshalInlineTable_IncompatibleType(t *testing.T) {
+	// Exercise the default branch of unmarshalInlineTable when the target
+	// is not a map, struct, or interface.
+	type doc struct {
+		A int `toml:"a"`
 	}
-
-	doc := `
-[section]
-sub.key = "value1"
-another.nested.key = "value2"
-`
-
-	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
-	assert.NoError(t, err)
-	assert.Equal(t, 2, len(cfg.Section.Keys))
-	// The dotted keys should be preserved in the raw output
-	assert.Equal(t, "value1", cfg.Section.Values["sub.key"])
-	assert.Equal(t, "value2", cfg.Section.Values["another.nested.key"])
+	var v doc
+	err := toml.Unmarshal([]byte(`a = {b = 1}`), &v)
+	assert.Error(t, err)
 }
 
-// Test pointer to pointer to Unmarshaler (covers pointer dereferencing loop)
-func TestIssue873_DoublePointerUnmarshaler(t *testing.T) {
-	type Config struct {
-		Section **customTable873 `toml:"section"`
+func TestTypeMismatchString_NoStructContext(t *testing.T) {
+	// Exercise the typeMismatchString code path without struct field context (line 186).
+	// Decoding a string into a bare int triggers this path.
+	var v map[string]int
+	err := toml.Unmarshal([]byte(`a = "hello"`), &v)
+	assert.Error(t, err)
+}
+
+func TestMultilineInlineTable_EmptyWithNewlines(t *testing.T) {
+	doc := "a = {\n\n}"
+	var v map[string]interface{}
+	err := toml.Unmarshal([]byte(doc), &v)
+	assert.NoError(t, err)
+	inner := v["a"]
+	if inner == nil {
+		t.Fatal("expected key 'a' to be present")
 	}
-
-	doc := `
-[section]
-key = "value"
-`
-
-	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
-	assert.NoError(t, err)
-	assert.True(t, cfg.Section != nil)
-	assert.True(t, *cfg.Section != nil)
-	assert.Equal(t, []string{"key"}, (*cfg.Section).Keys)
-	assert.Equal(t, "value", (*cfg.Section).Values["key"])
-}
-
-// formattingCapture captures the raw TOML bytes to verify formatting preservation
-type formattingCapture struct {
-	RawBytes string
-}
-
-func (f *formattingCapture) UnmarshalTOML(data []byte) error {
-	f.RawBytes = string(data)
-	return nil
-}
-
-func TestIssue873_FormattingPreservation(t *testing.T) {
-	type Config struct {
-		Section *formattingCapture `toml:"section"`
+	m, ok := inner.(map[string]interface{})
+	if !ok {
+		t.Fatalf("expected map, got %T", inner)
+	}
+	if len(m) != 0 {
+		t.Fatalf("expected empty map, got %v", m)
+	}
+}
+
+func TestMultilineInlineTable_CommentsOnly(t *testing.T) {
+	doc := "a = {\n  # just a comment\n}"
+	var v map[string]interface{}
+	err := toml.Unmarshal([]byte(doc), &v)
+	assert.NoError(t, err)
+	inner := v["a"]
+	if inner == nil {
+		t.Fatal("expected key 'a' to be present")
+	}
+	m, ok := inner.(map[string]interface{})
+	if !ok {
+		t.Fatalf("expected map, got %T", inner)
+	}
+	if len(m) != 0 {
+		t.Fatalf("expected empty map, got %v", m)
+	}
+}
+
+func TestMultilineInlineTable_CommentAfterComma(t *testing.T) {
+	// Exercises comment handling after comma in inline table (parser lines 518-524).
+	doc := "a = { b = 1, # comment\nc = 2 }"
+	var v map[string]interface{}
+	err := toml.Unmarshal([]byte(doc), &v)
+	assert.NoError(t, err)
+	m, ok := v["a"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected a map")
+	}
+	if m["b"] != int64(1) {
+		t.Fatalf("expected b=1, got %v", m["b"])
+	}
+	if m["c"] != int64(2) {
+		t.Fatalf("expected c=2, got %v", m["c"])
+	}
+}
+
+func TestMultilineInlineTable_CommentAfterValue(t *testing.T) {
+	// Exercises comment handling after keyval in inline table (parser lines 542-548).
+	doc := "a = { b = 1 # comment\n, c = 2 }"
+	var v map[string]interface{}
+	err := toml.Unmarshal([]byte(doc), &v)
+	assert.NoError(t, err)
+	m, ok := v["a"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected a map")
+	}
+	if m["b"] != int64(1) {
+		t.Fatalf("expected b=1, got %v", m["b"])
+	}
+	if m["c"] != int64(2) {
+		t.Fatalf("expected c=2, got %v", m["c"])
+	}
+}
+
+func TestMultilineInlineTable_LeadingComma(t *testing.T) {
+	doc := "a = { b = 1\n, c = 2 }"
+	var v map[string]interface{}
+	err := toml.Unmarshal([]byte(doc), &v)
+	assert.NoError(t, err)
+	m, ok := v["a"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected a map")
+	}
+	if m["b"] != int64(1) {
+		t.Fatalf("expected b=1, got %v", m["b"])
+	}
+	if m["c"] != int64(2) {
+		t.Fatalf("expected c=2, got %v", m["c"])
 	}
-
-	// Test that various formatting styles are preserved:
-	// - Extra spaces around '='
-	// - Literal strings (single quotes)
-	// - Hex numbers
-	// - Inline tables
-	doc := `[section]
-key1   =   "value with spaces"
-key2 = 'literal string'
-hex_val = 0xDEADBEEF
-inline = { a = 1, b = 2 }
-`
-
-	var cfg Config
-	err := toml.NewDecoder(bytes.NewReader([]byte(doc))).
-		EnableUnmarshalerInterface().
-		Decode(&cfg)
-
-	assert.NoError(t, err)
-	assert.True(t, cfg.Section != nil)
-
-	// The raw bytes should preserve original formatting
-	raw := cfg.Section.RawBytes
-
-	// Check that extra spaces around '=' are preserved
-	assert.True(t, strings.Contains(raw, "key1   =   \"value with spaces\""),
-		"Expected spacing to be preserved, got: %s", raw)
-
-	// Check that literal string style is preserved
-	assert.True(t, strings.Contains(raw, "key2 = 'literal string'"),
-		"Expected literal string to be preserved, got: %s", raw)
-
-	// Check that hex format is preserved
-	assert.True(t, strings.Contains(raw, "hex_val = 0xDEADBEEF"),
-		"Expected hex format to be preserved, got: %s", raw)
-
-	// Check that inline table is preserved
-	assert.True(t, strings.Contains(raw, "inline = { a = 1, b = 2 }"),
-		"Expected inline table to be preserved, got: %s", raw)
 }

unstable/parser.go

@@ -328,9 +328,6 @@ func (p *Parser) parseStdTable(b []byte) (reference, []byte, error) {
 
 func (p *Parser) parseKeyval(b []byte) (reference, []byte, error) {
 	// keyval = key keyval-sep val
-	// Track the start position for Raw range
-	startB := b
-
 	ref := p.builder.Push(Node{
 		Kind: KeyValue,
 	})
@@ -363,10 +360,6 @@ func (p *Parser) parseKeyval(b []byte) (reference, []byte, error) {
 	p.builder.Chain(valRef, key)
 	p.builder.AttachChild(ref, valRef)
 
-	// Set Raw to span the entire key-value expression
-	node := p.builder.NodeAt(ref)
-	node.Raw = p.rangeOfToken(startB[:len(startB)-len(b)], b)
-
 	return ref, b, err
 }
 
@@ -467,12 +460,14 @@ func (p *Parser) parseLiteralString(b []byte) ([]byte, []byte, []byte, error) {
 	return v, v[1 : len(v)-1], rest, nil
 }
 
+//nolint:funlen,cyclop,dupl
 func (p *Parser) parseInlineTable(b []byte) (reference, []byte, error) {
 	// inline-table = inline-table-open [ inline-table-keyvals ] inline-table-close
 	// inline-table-open  = %x7B ws     ; {
 	// inline-table-close = ws %x7D     ; }
 	// inline-table-sep   = ws %x2C ws  ; , Comma
 	// inline-table-keyvals = keyval [ inline-table-sep inline-table-keyvals ]
+	tableStart := b
 	parent := p.builder.Push(Node{
 		Kind: InlineTable,
 		Raw:  p.rangeOfToken(b[:1], b[1:]),
@@ -480,45 +475,77 @@ func (p *Parser) parseInlineTable(b []byte) (reference, []byte, error) {
 
 	first := true
 
-	var child reference
+	lastChild := invalidReference
+
+	addChild := func(ref reference) {
+		if lastChild == invalidReference {
+			p.builder.AttachChild(parent, ref)
+		} else {
+			p.builder.Chain(lastChild, ref)
+		}
+		lastChild = ref
+	}
 
 	b = b[1:]
 
 	var err error
 
 	for len(b) > 0 {
-		previousB := b
-		b = p.parseWhitespace(b)
+		var cref reference
+		cref, b, err = p.parseOptionalWhitespaceCommentNewline(b)
+		if err != nil {
+			return parent, nil, err
+		}
+
+		if cref != invalidReference {
+			addChild(cref)
+		}
 
 		if len(b) == 0 {
-			return parent, nil, NewParserError(previousB[:1], "inline table is incomplete")
+			return parent, nil, NewParserError(tableStart[:1], "inline table is incomplete")
 		}
 
 		if b[0] == '}' {
 			break
 		}
 
-		if !first {
-			b, err = expect(',', b)
+		if b[0] == ',' {
+			if first {
+				return parent, nil, NewParserError(b[0:1], "inline table cannot start with comma")
+			}
+			b = b[1:]
+
+			cref, b, err = p.parseOptionalWhitespaceCommentNewline(b)
 			if err != nil {
 				return parent, nil, err
 			}
-			b = p.parseWhitespace(b)
+			if cref != invalidReference {
+				addChild(cref)
+			}
+		} else if !first {
+			return parent, nil, NewParserError(b[0:1], "inline table entries must be separated by commas")
+		}
+
+		// trailing comma: if '}' follows, stop
+		if len(b) > 0 && b[0] == '}' {
+			break
 		}
 
 		var kv reference
-
 		kv, b, err = p.parseKeyval(b)
 		if err != nil {
 			return parent, nil, err
 		}
 
-		if first {
-			p.builder.AttachChild(parent, kv)
-		} else {
-			p.builder.Chain(child, kv)
+		addChild(kv)
+
+		cref, b, err = p.parseOptionalWhitespaceCommentNewline(b)
+		if err != nil {
+			return parent, nil, err
+		}
+		if cref != invalidReference {
+			addChild(cref)
 		}
-		child = kv
 
 		first = false
 	}
@@ -528,7 +555,7 @@ func (p *Parser) parseInlineTable(b []byte) (reference, []byte, error) {
 	return parent, rest, err
 }
 
-//nolint:funlen,cyclop
+//nolint:funlen,cyclop,dupl
 func (p *Parser) parseValArray(b []byte) (reference, []byte, error) {
 	// array = array-open [ array-values ] ws-comment-newline array-close
 	// array-open =  %x5B ; [
@@ -792,6 +819,13 @@ func (p *Parser) parseMultilineBasicString(b []byte) ([]byte, []byte, []byte, er
 				builder.WriteByte('\t')
 			case 'e':
 				builder.WriteByte(0x1B)
+			case 'x':
+				x, err := hexToRune(atmost(token[i+1:], 2), 2)
+				if err != nil {
+					return nil, nil, nil, err
+				}
+				builder.WriteRune(x)
+				i += 2
 			case 'u':
 				x, err := hexToRune(atmost(token[i+1:], 4), 4)
 				if err != nil {
@@ -951,6 +985,13 @@ func (p *Parser) parseBasicString(b []byte) ([]byte, []byte, []byte, error) {
 				builder.WriteByte('\t')
 			case 'e':
 				builder.WriteByte(0x1B)
+			case 'x':
+				x, err := hexToRune(token[i+1:len(token)-1], 2)
+				if err != nil {
+					return nil, nil, nil, err
+				}
+				builder.WriteRune(x)
+				i += 2
 			case 'u':
 				x, err := hexToRune(token[i+1:len(token)-1], 4)
 				if err != nil {

unstable/parser_test.go

@@ -331,6 +331,154 @@ func TestParser_AST(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc:  "multiline inline table",
+			input: "name = {\n  first = \"Tom\",\n  last = \"Preston-Werner\"\n}",
+			ast: astNode{
+				Kind: KeyValue,
+				Children: []astNode{
+					{
+						Kind: InlineTable,
+						Children: []astNode{
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Tom`)},
+									{Kind: Key, Data: []byte(`first`)},
+								},
+							},
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Preston-Werner`)},
+									{Kind: Key, Data: []byte(`last`)},
+								},
+							},
+						},
+					},
+					{
+						Kind: Key,
+						Data: []byte(`name`),
+					},
+				},
+			},
+		},
+		{
+			desc:  "inline table with trailing comma",
+			input: `name = { first = "Tom", last = "Preston-Werner", }`,
+			ast: astNode{
+				Kind: KeyValue,
+				Children: []astNode{
+					{
+						Kind: InlineTable,
+						Children: []astNode{
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Tom`)},
+									{Kind: Key, Data: []byte(`first`)},
+								},
+							},
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Preston-Werner`)},
+									{Kind: Key, Data: []byte(`last`)},
+								},
+							},
+						},
+					},
+					{
+						Kind: Key,
+						Data: []byte(`name`),
+					},
+				},
+			},
+		},
+		{
+			desc:  "empty inline table with newline",
+			input: "name = {\n}",
+			ast: astNode{
+				Kind: KeyValue,
+				Children: []astNode{
+					{
+						Kind:     InlineTable,
+						Children: nil,
+					},
+					{
+						Kind: Key,
+						Data: []byte(`name`),
+					},
+				},
+			},
+		},
+		{
+			desc:  "inline table with leading comma",
+			input: "name = { first = \"Tom\"\n, last = \"Werner\" }",
+			ast: astNode{
+				Kind: KeyValue,
+				Children: []astNode{
+					{
+						Kind: InlineTable,
+						Children: []astNode{
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Tom`)},
+									{Kind: Key, Data: []byte(`first`)},
+								},
+							},
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Werner`)},
+									{Kind: Key, Data: []byte(`last`)},
+								},
+							},
+						},
+					},
+					{
+						Kind: Key,
+						Data: []byte(`name`),
+					},
+				},
+			},
+		},
+		{
+			desc:  "inline table with leading trailing comma",
+			input: "name = { first = \"Tom\"\n, }",
+			ast: astNode{
+				Kind: KeyValue,
+				Children: []astNode{
+					{
+						Kind: InlineTable,
+						Children: []astNode{
+							{
+								Kind: KeyValue,
+								Children: []astNode{
+									{Kind: String, Data: []byte(`Tom`)},
+									{Kind: Key, Data: []byte(`first`)},
+								},
+							},
+						},
+					},
+					{
+						Kind: Key,
+						Data: []byte(`name`),
+					},
+				},
+			},
+		},
+		{
+			desc:  "inline table comma at start is error",
+			input: "name = { , first = \"Tom\" }",
+			err:   true,
+		},
+		{
+			desc:  "inline table double comma across newline is error",
+			input: "name = { first = \"Tom\",\n, last = \"Werner\" }",
+			err:   true,
+		},
 	}
 
 	for _, e := range examples {
@@ -350,6 +498,44 @@ func TestParser_AST(t *testing.T) {
 	}
 }
 
+func TestParseInlineTable_CommentsWithKeepComments(t *testing.T) {
+	// Exercise comment reference handling inside parseInlineTable when
+	// KeepComments is true. This covers the addChild(cref) branches
+	// at the start of the loop, after comma, and after keyval.
+	examples := []struct {
+		desc  string
+		input string
+	}{
+		{
+			desc:  "comment at start of inline table",
+			input: "a = {\n# comment\nb = 1\n}",
+		},
+		{
+			desc:  "comment after comma",
+			input: "a = {b = 1,\n# comment\nc = 2\n}",
+		},
+		{
+			desc:  "comment after keyval",
+			input: "a = {b = 1 # comment\n, c = 2}",
+		},
+		{
+			desc:  "comment only in inline table",
+			input: "a = {\n# just a comment\n}",
+		},
+	}
+
+	for _, e := range examples {
+		e := e
+		t.Run(e.desc, func(t *testing.T) {
+			p := Parser{KeepComments: true}
+			p.Reset([]byte(e.input))
+			p.NextExpression()
+			err := p.Error()
+			assert.NoError(t, err)
+		})
+	}
+}
+
 func BenchmarkParseBasicStringWithUnicode(b *testing.B) {
 	p := &Parser{}
 	b.Run("4", func(b *testing.B) {
@@ -539,7 +725,7 @@ key5 = [ # Next to start of inline array.
 	// ---
 	// 6:1->6:22 (105->126)      | Comment [# Above simple value.]
 	// ---
-	// 7:1->7:14 (127->140)      | KeyValue []
+	// 1:1->1:1 (0->0)           | KeyValue []
 	// 7:7->7:14 (133->140)      |   String [value]
 	// 7:1->7:4 (127->130)       |   Key [key]
 	// 7:15->7:38 (141->164)     | Comment [# Next to simple value.]
@@ -552,12 +738,12 @@ key5 = [ # Next to start of inline array.
 	// ---
 	// 14:1->14:22 (252->273)    | Comment [# Above inline table.]
 	// ---
-	// 15:1->15:50 (274->323)    | KeyValue []
+	// 1:1->1:1 (0->0)           | KeyValue []
 	// 15:8->15:9 (281->282)     |   InlineTable []
-	// 15:10->15:23 (283->296)   |     KeyValue []
+	// 1:1->1:1 (0->0)           |     KeyValue []
 	// 15:18->15:23 (291->296)   |       String [Tom]
 	// 15:10->15:15 (283->288)   |       Key [first]
-	// 15:25->15:48 (298->321)   |     KeyValue []
+	// 1:1->1:1 (0->0)           |     KeyValue []
 	// 15:32->15:48 (305->321)   |       String [Preston-Werner]
 	// 15:25->15:29 (298->302)   |       Key [last]
 	// 15:1->15:5 (274->278)     |   Key [name]
@@ -567,7 +753,7 @@ key5 = [ # Next to start of inline array.
 	// ---
 	// 18:1->18:15 (371->385)    | Comment [# Above array.]
 	// ---
-	// 19:1->19:20 (386->405)    | KeyValue []
+	// 1:1->1:1 (0->0)           | KeyValue []
 	// 1:1->1:1 (0->0)           |   Array []
 	// 19:11->19:12 (396->397)   |     Integer [1]
 	// 19:14->19:15 (399->400)   |     Integer [2]
@@ -579,7 +765,7 @@ key5 = [ # Next to start of inline array.
 	// ---
 	// 22:1->22:26 (448->473)    | Comment [# Above multi-line array.]
 	// ---
-	// 23:1->31:2 (474->694)     | KeyValue []
+	// 1:1->1:1 (0->0)           | KeyValue []
 	// 1:1->1:1 (0->0)           |   Array []
 	// 23:10->23:42 (483->515)   |     Comment [# Next to start of inline array.]
 	// 24:3->24:38 (518->553)    |       Comment [# Second line before array content.]

unstable/unmarshaler.go

@@ -1,32 +1,7 @@
 package unstable
 
-// Unmarshaler is implemented by types that can unmarshal a TOML
-// description of themselves. The input is a valid TOML document
-// containing the relevant portion of the parsed document.
-//
-// For tables (including split tables defined in multiple places),
-// the data contains the raw key-value bytes from the original document
-// with adjusted table headers to be relative to the unmarshaling target.
+// The Unmarshaler interface may be implemented by types to customize their
+// behavior when being unmarshaled from a TOML document.
 type Unmarshaler interface {
-	UnmarshalTOML(data []byte) error
-}
-
-// RawMessage is a raw encoded TOML value. It implements Unmarshaler
-// and can be used to delay TOML decoding or capture raw content.
-//
-// Example usage:
-//
-//	type Config struct {
-//	    Plugin RawMessage `toml:"plugin"`
-//	}
-//
-//	var cfg Config
-//	toml.NewDecoder(r).EnableUnmarshalerInterface().Decode(&cfg)
-//	// cfg.Plugin now contains the raw TOML bytes for [plugin]
-type RawMessage []byte
-
-// UnmarshalTOML implements Unmarshaler.
-func (m *RawMessage) UnmarshalTOML(data []byte) error {
-	*m = append((*m)[0:0], data...)
-	return nil
+	UnmarshalTOML(value *Node) error
 }