Throw FallThroughError when we fall through a case in a switch statement. Fixes

parser.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // TODO(jimhug): Error recovery needs major work!
 /**
  * A simple recursive descent parser for the dart language.
  *
  * This parser is designed to be more permissive than the official
  * Dart grammar.  It is expected that many grammar errors would be
@@ skipping 601 matching lines @@
     var cases = [];
     _eat(TokenKind.LBRACE);
     while (!_maybeEat(TokenKind.RBRACE)) {
       cases.add(caseNode());
     }
     return new SwitchStatement(test, cases, _makeSpan(start));
   }
 
   _peekCaseEnd() {
     var kind = _peek();
+    //TODO(efortuna): also if the first is an identifier followed by a colon, we
+    //have a label for the case statement.
     return kind == TokenKind.RBRACE || kind == TokenKind.CASE ||
       kind == TokenKind.DEFAULT;
   }
 
   caseNode() {
     int start = _peekToken.start;
     var label = null;
     if (_peekIdentifier()) {
+      label = identifier();

[jimhug, 2011/10/28 20:02:44]

Whoa!  How was this working before?

       _eat(TokenKind.COLON);
-      label = identifier();
     }
     var cases = [];
     while (true) {
       if (_maybeEat(TokenKind.CASE)) {
         cases.add(expression());
         _eat(TokenKind.COLON);
       } else if (_maybeEat(TokenKind.DEFAULT)) {
         cases.add(null);
         _eat(TokenKind.COLON);
       } else {
@@ skipping 978 matching lines @@
   /** Converts an expression into a label. */
   _makeLabel(expr) {
     if (expr is VarExpression) {
       return expr.name;
     } else {
       _errorExpected('label');
       return null;
     }
   }
 }