Allow unknown at-rules within CSS rules. Fixes #123

microsoft · Oct 29, 2018 · 9686d20 · 9686d20
1 parent 0bba3ee
commit 9686d20
Show file tree

Hide file tree

Showing 2 changed files with 10 additions and 1 deletion.
diff --git a/src/parser/cssParser.ts b/src/parser/cssParser.ts
@@ -320,7 +320,11 @@ export class Parser {
 	}
 
 	public _parseRuleSetDeclaration(): nodes.Node {
-		return this._parseAtApply() || this._tryParseCustomPropertyDeclaration() || this._parseDeclaration();
+		// https://www.w3.org/TR/css-syntax-3/#consume-a-list-of-declarations0
+		return this._parseAtApply()
+			|| this._tryParseCustomPropertyDeclaration()
+			|| this._parseDeclaration()
+			|| this._parseUnknownAtRule();
 	}
 
 	/**
@@ -999,6 +1003,10 @@ export class Parser {
 
 	// https://www.w3.org/TR/css-syntax-3/#consume-an-at-rule
 	public _parseUnknownAtRule(): nodes.Node {
+		if (!this.peek(TokenType.AtKeyword)) {
+			return null;
+		}
+
 		let node = <nodes.UnknownAtRule>this.create(nodes.UnknownAtRule);
 		node.addChild(this._parseUnknownAtRuleName());
 

diff --git a/src/test/css/parser.test.ts b/src/test/css/parser.test.ts
@@ -82,6 +82,7 @@ suite('CSS - Parser', () => {
 		assertNode('@unknown-rule (foo) {}', parser, parser._parseStylesheet.bind(parser));
 		assertNode('@unknown-rule (foo) { .bar {} }', parser, parser._parseStylesheet.bind(parser));
 		assertNode('@mskeyframes darkWordHighlight { from { background-color: inherit; } to { background-color: rgba(83, 83, 83, 0.7); } }', parser, parser._parseStylesheet.bind(parser));
+		assertNode('foo { @unknown-rule; }', parser, parser._parseStylesheet.bind(parser));
 
 		assertError('@unknown-rule (;', parser, parser._parseStylesheet.bind(parser), ParseError.RightParenthesisExpected);
 		assertError('@unknown-rule [foo', parser, parser._parseStylesheet.bind(parser), ParseError.RightSquareBracketExpected);