feat: allow newlines and trailing commas in inline tables

TOML v1.1.0 relaxes inline table syntax to allow newlines, comments,
and trailing commas, matching the existing behavior of arrays.

toml_testgen_test.go

@@ -743,25 +743,8 @@ func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Empty3(t *testing.T) {
 	testgenInvalid(t, input)
 }
 
-func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Linebreak1(t *testing.T) {
+// TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Linebreak1 through Linebreak4
-	input := "# No newlines are allowed between the curly braces unless they are valid within\n# a value.\nsimple = { a = 1 \n}\n"
+// are removed because TOML v1.1.0 allows newlines in inline tables.
-	testgenInvalid(t, input)
-}
-
-func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Linebreak2(t *testing.T) {
-	input := "t = {a=1,\nb=2}\n"
-	testgenInvalid(t, input)
-}
-
-func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Linebreak3(t *testing.T) {
-	input := "t = {a=1\n,b=2}\n"
-	testgenInvalid(t, input)
-}
-
-func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Linebreak4(t *testing.T) {
-	input := "json_like = {\n          first = \"Tom\",\n          last = \"Preston-Werner\"\n}\n"
-	testgenInvalid(t, input)
-}
 
 func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_NoClose1(t *testing.T) {
 	input := "a={\n"
@@ -833,10 +816,8 @@ func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_Overwrite10(t *testing.T) {
 	testgenInvalid(t, input)
 }
 
-func TestTOMLTest_Invalid_Tests_Invalid_InlineTable_TrailingComma(t *testing.T) {
+// TestTOMLTest_Invalid_Tests_Invalid_InlineTable_TrailingComma is removed
-	input := "# A terminating comma (also called trailing comma) is not permitted after the\n# last key/value pair in an inline table\nabc = { abc = 123, }\n"
+// because TOML v1.1.0 allows trailing commas in inline tables.
-	testgenInvalid(t, input)
-}
 
 func TestTOMLTest_Invalid_Tests_Invalid_Integer_CapitalBin(t *testing.T) {
 	input := "capital-bin = 0B0\n"

unmarshaler_test.go

@@ -1094,6 +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"}]`,

unstable/parser.go

@@ -460,12 +460,14 @@ func (p *Parser) parseLiteralString(b []byte) ([]byte, []byte, []byte, error) {
 	return v, v[1 : len(v)-1], rest, nil
 }
 
+//nolint:funlen,cyclop
 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:]),
@@ -473,45 +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
+		var cref reference
-		b = p.parseWhitespace(b)
+		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 {
+		if b[0] == ',' {
-			b, err = expect(',', b)
+			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 {
+		addChild(kv)
-			p.builder.AttachChild(parent, kv)
+
-		} else {
+		cref, b, err = p.parseOptionalWhitespaceCommentNewline(b)
-			p.builder.Chain(child, kv)
+		if err != nil {
+			return parent, nil, err
+		}
+		if cref != invalidReference {
+			addChild(cref)
 		}
-		child = kv
 
 		first = false
 	}

unstable/parser_test.go

@@ -331,6 +331,87 @@ 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`),
+					},
+				},
+			},
+		},
 	}
 
 	for _, e := range examples {