internal/*: add support for raw values (for grid)

Note that this doesn't strip whitespace from raw values.

Author: stephen

internal/ast/value.go

@@ -96,6 +96,13 @@ type MathParenthesizedExpression struct {
 	Value Value
 }
 
+// Raw is an otherwise non-structured but valid value.
+type Raw struct {
+	Span
+
+	Value string
+}
+
 // Comma is a single comma. Some declarations require commas,
 // e.g. font-family fallbacks or transitions.
 type Comma struct {
@@ -110,6 +117,7 @@ func (MathParenthesizedExpression) isValue() {}
 func (Comma) isValue()                       {}
 func (Identifier) isValue()                  {}
 func (HexColor) isValue()                    {}
+func (Raw) isValue()                         {}
 
 var _ Value = String{}
 var _ Value = Dimension{}
@@ -119,3 +127,4 @@ var _ Value = MathParenthesizedExpression{}
 var _ Value = Comma{}
 var _ Value = Identifier{}
 var _ Value = HexColor{}
+var _ Value = Raw{}

internal/integration_test.go

@@ -16,6 +16,7 @@ func TestIntegration(t *testing.T) {
 		"testdata/comments.css",
 		"testdata/bem.css",
 		"testdata/font-face.css",
+		"testdata/grid.css",
 	} {
 		t.Run(c, func(t *testing.T) {
 

internal/parser/parser.go

@@ -141,9 +141,15 @@ func (p *parser) parseDeclarationBlock() *ast.DeclarationBlock {
 			case lexer.EOF:
 				p.lexer.Errorf("unexpected EOF")
 
+			case lexer.Comma:
+				decl.Values = append(decl.Values, &ast.Comma{Span: p.lexer.TokenSpan()})
+				p.lexer.Next()
+
 			case lexer.Delim:
 				if p.lexer.CurrentString != "!" {
-					p.lexer.Errorf("unexpected token: %s", p.lexer.CurrentString)
+					decl.Values = append(decl.Values, &ast.Raw{Span: p.lexer.TokenSpan(), Value: p.lexer.CurrentString})
+					p.lexer.Next()
+					continue
 				}
 				p.lexer.Next()
 
@@ -154,10 +160,6 @@ func (p *parser) parseDeclarationBlock() *ast.DeclarationBlock {
 				p.lexer.Next()
 				decl.Important = true
 
-			case lexer.Comma:
-				decl.Values = append(decl.Values, &ast.Comma{Span: p.lexer.TokenSpan()})
-				p.lexer.Next()
-
 			default:
 				val := p.parseValue()
 				if val == nil {

internal/printer/printer.go

@@ -363,6 +363,9 @@ func (p *printer) print(in ast.Node) {
 		}
 		p.s.WriteRune(')')
 
+	case *ast.Raw:
+		p.s.WriteString(node.Value)
+
 	default:
 		panic(fmt.Sprintf("unknown ast node: %s", reflect.TypeOf(in).String()))
 	}

internal/testdata/grid.css

@@ -0,0 +1,19 @@
+.a {
+  grid-column: 1 / span 2;
+  grid-template: "text" auto "meter" 1fr / 1fr;
+}
+
+.b {
+  grid-column: 3 ;
+  grid-row: 1 / span 2;
+}
+
+.c {
+  grid-column: 1 ;
+  grid-row: 2 ;
+}
+
+.d {
+  grid-column: 2 ;
+  grid-row: 2 ;
+}