fix #136, support watch exprs and two way bindings for component fields

test/emitter_test.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.
 
 /**
  * These are not quite unit tests, since we build on top of the analyzer and the
  * html5parser to build the input for each test.
  */
 library emitter_test;
 
@@ skipping 158 matching lines @@
   group('emit text node field', () {
     test('declaration', () {
       var elem = parseSubtree('<div>{{bar}}</div>');
       var emitter = new ContentFieldEmitter(analyzeElement(elem).children[0]);
       expect(_declarations(emitter), 'var __binding0;');
     });
 
     test('created', () {
       var elem = parseSubtree('<div>{{bar}}</div>');
       var emitter = new ContentFieldEmitter(analyzeElement(elem).children[0]);
-      expect(_created(emitter),
-        '__binding0 = autogenerated.nodeForBinding(bar);');
+      expect(_created(emitter), "__binding0 = new autogenerated.Text('');");
     });
 
     test('inserted', () {
       var elem = parseSubtree('<div>{{bar}}</div>');
       var emitter = new ContentFieldEmitter(analyzeElement(elem).children[0]);
       expect(_inserted(emitter), '');
     });
 
     test('removed', () {
       var elem = parseSubtree('<div>{{bar}}</div>');
@@ skipping 62 matching lines @@
       var elem = parseSubtree('<div foo="{{bar}}"></div>');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_created(emitter), equals('__stoppers1 = [];'));
     });
 
     test('inserted', () {
       var elem = parseSubtree('<div foo="{{bar}}"></div>');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => '
-          'bar, (__e) { __e0.attributes["foo"] = __e.newValue; }));'));
+          "bar, (__e) { __e0.attributes['foo'] = __e.newValue; }));"));
     });
 
     test('inserted for 1-way binding with dom accessor', () {
       var elem = parseSubtree('<input value="{{bar}}">');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => bar, (__e) { '
           '__e0.value = __e.newValue; }));'));
     });
 
     test('inserted for 2-way binding with dom accessor', () {
       var elem = parseSubtree('<input data-bind="value:bar">');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => bar, (__e) { '
           '__e0.value = __e.newValue; }));'));
     });
 
     test('inserted for data attribute', () {
       var elem = parseSubtree('<div data-foo="{{bar}}"></div>');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace(
           '__stoppers1.add(autogenerated.watchAndInvoke(() => bar, (__e) { '
-          '__e0.attributes["data-foo"] = __e.newValue; }));'));
+          "__e0.attributes['data-foo'] = __e.newValue; }));"));
     });
 
     test('inserted for class', () {
       var elem = parseSubtree('<div class="{{bar}} {{foo}}" />');
       var emitter = new AttributeEmitter(analyzeElement(elem));
       expect(_inserted(emitter), equalsIgnoringWhitespace('''
           __stoppers1.add(autogenerated.bindCssClasses(__e0, () => bar));
           __stoppers1.add(autogenerated.bindCssClasses(__e0, () => foo));
           '''));
     });
@@ skipping 96 matching lines @@
   var context = new Context();
   new RecursiveEmitter(null, context).visit(info);
   return context.createdMethod.toString().trim();
 }
 
 _declarationsRecursive(ElementInfo info) {
   var context = new Context();
   new RecursiveEmitter(null, context).visit(info);
   return context.declarations.toString().trim();
 }