Cleanup bugs in wrapExpressionAsClosure Fix bug in how setters were handled and filter out 'this' f…

tools/dom/src/native_DOMImplementation.dart

 // Copyright (c) 2012, 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.
 
 part of html;
 
 class _ConsoleVariables {
   Map<String, Object> _data = new Map<String, Object>();
   
   /**
    * Forward member accesses to the backing JavaScript object.
    */
   noSuchMethod(Invocation invocation) {
     String member = MirrorSystem.getName(invocation.memberName);
     if (invocation.isGetter) {
       return _data[member];
     } else if (invocation.isSetter) {
+      assert(member.endsWith('='));
+      member = member.substring(0, member.length - 1);
       _data[member] = invocation.positionalArguments[0];
     } else {
       return Function.apply(_data[member], invocation.positionalArguments, invocation.namedArguments);
     }
   }
   
   void clear() => _data.clear();
 
   /**
    * List all variables currently defined.
@@ skipping 98 matching lines @@
     }
     return map;
   }
 
   static _ConsoleVariables _consoleTempVariables = new _ConsoleVariables();
   /**
    * Takes an [expression] and a list of [local] variable and returns an
    * expression for a closure with a body matching the original expression
    * where locals are passed in as arguments. Returns a list containing the
    * String expression for the closure and the list of arguments that should
-   * be passed to it.
+   * be passed to it. The expression should then be evaluated using
+   * Dart_EvaluateExpr which will generate a closure that should be invoked
+   * with the list of arguments passed to this method.
    *
    * For example:
    * <code>wrapExpressionAsClosure("foo + bar", ["bar", 40, "foo", 2])</code>
    * will return:
    * <code>["(final $var, final bar, final foo) => foo + bar", [40, 2]]</code>
    */
   static List wrapExpressionAsClosure(String expression, List locals) {
     var args = {};
     var sb = new StringBuffer("(");
     addArg(arg, value) {
       arg = stripMemberName(arg);
       if (args.containsKey(arg)) return;
+      // We ignore arguments with the name 'this' rather than throwing an
+      // exception because Dart_GetLocalVariables includes 'this' and it
+      // is more convenient to filter it out here than from C++ code.
+      // 'this' needs to be handled by calling Dart_EvaluateExpr with
+      // 'this' as the target rather than by passing it as an argument.
+      if (arg == 'this') return;
       if (args.isNotEmpty) {
         sb.write(", ");
       }
       sb.write("final $arg");
       args[arg] = value;
     }
     
     addArg("\$var", _consoleTempVariables);
     
     for (int i = 0; i < locals.length; i+= 2) {
@@ skipping 331 matching lines @@
   _send(msg) {
     _sendToHelperIsolate(msg, _sendPort);
   }
 
   bool get isActive => _isActive;
 }
 
 get _pureIsolateTimerFactoryClosure =>
     ((int milliSeconds, void callback(Timer time), bool repeating) =>
         new _PureIsolateTimer(milliSeconds, callback, repeating));