Updated parser with support for unknown @ rule error recovery (fixes #211)

Author: Nicholas C. Zakas

lib/parserlib.js

@@ -21,7 +21,7 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 
 */
-/* Build time: 1-November-2011 12:11:55 */
+/* Build time: 16-November-2011 01:11:51 */
 var parserlib = {};
 (function(){
 
@@ -925,7 +925,7 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 
 */
-/* Build time: 1-November-2011 12:11:55 */
+/* Build time: 16-November-2011 01:11:51 */
 (function(){
 var EventTarget = parserlib.util.EventTarget,
 TokenStreamBase = parserlib.util.TokenStreamBase,
@@ -1258,6 +1258,7 @@ Parser.prototype = function(){
 
                 var tokenStream = this._tokenStream,
                     charset     = null,
+                    count,
                     token,
                     tt;
 
@@ -1304,7 +1305,36 @@ Parser.prototype = function(){
                             case Tokens.KEYFRAMES_SYM:
                                 this._keyframes(); 
                                 this._skipCruft();
-                                break;  
+                                break;                                
+                            case Tokens.UNKNOWN_SYM:  //unknown @ rule
+                                tokenStream.get();
+                                if (!this.options.strict){
+                                
+                                    //fire error event
+                                    this.fire({
+                                        type:       "error",
+                                        error:      null,
+                                        message:    "Unknown @ rule: " + tokenStream.LT(0).value + ".",
+                                        line:       tokenStream.LT(0).startLine,
+                                        col:        tokenStream.LT(0).startCol
+                                    });                          
+                                    
+                                    //skip braces
+                                    count=0;
+                                    while (tokenStream.advance([Tokens.LBRACE, Tokens.RBRACE]) == Tokens.LBRACE){
+                                        count++;    //keep track of nesting depth
+                                    }
+                                    
+                                    while(count){
+                                        tokenStream.advance([Tokens.RBRACE]);
+                                        count--;
+                                    }
+                                    
+                                } else {
+                                    //not a syntax error, rethrow it
+                                    throw new SyntaxError("Unknown @ rule.", tokenStream.LT(0).startLine, tokenStream.LT(0).startCol);;
+                                }                                
+                                break;
                             case Tokens.S:
                                 this._readWhitespace();
                                 break;
@@ -4728,9 +4758,13 @@ TokenStream.prototype = mix(new TokenStreamBase(), {
 
         //if it's not valid, use the first character only and reset the reader
         if (tt == Tokens.CHAR || tt == Tokens.UNKNOWN){
-            tt = Tokens.CHAR;
-            rule = first;
-            reader.reset();
+            if (rule.length > 1){
+                tt = Tokens.UNKNOWN_SYM;                
+            } else {
+                tt = Tokens.CHAR;
+                rule = first;
+                reader.reset();
+            }
         }
 
         return this.createToken(tt, rule, startLine, startCol);
@@ -5396,6 +5430,7 @@ var Tokens  = [
     { name: "FONT_FACE_SYM", text: "@font-face"},
     { name: "CHARSET_SYM", text: "@charset"},
     { name: "NAMESPACE_SYM", text: "@namespace"},
+    { name: "UNKNOWN_SYM" },
     //{ name: "ATKEYWORD"},
 
     //CSS3 animations