A few API changes:

tests/html/js_test.dart

 // Copyright (c) 2013, 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.
 
 library jsTest;
 
 import 'dart:async';
 import 'dart:html';
 import 'dart:js';
 
@@ skipping 192 matching lines @@
 
     test('retrieve same dart Object', () {
       final date = new DateTime.now();
       context['dartDate'] = date;
       expect(context['dartDate'], same(date));
       context.deleteProperty('dartDate');
     });
 
   });
 
-  test('read global field', () {
-    expect(context['x'], equals(42));
-    expect(context['y'], isNull);
-  });
-
-  test('read global field with underscore', () {
-    expect(context['_x'], equals(123));
-    expect(context['y'], isNull);
-  });
-
-  test('hashCode and operator==(other)', () {
-    final o1 = context['Object'];
-    final o2 = context['Object'];
-    expect(o1 == o2, isTrue);
-    expect(o1.hashCode == o2.hashCode, isTrue);
-    final d = context['document'];
-    expect(o1 == d, isFalse);
-  });
-
-  test('js instantiation : new Foo()', () {
-    final Foo2 = context['container']['Foo'];
-    final foo = new JsObject(Foo2, [42]);
-    expect(foo['a'], 42);
-    expect(Foo2['b'], 38);
-  });
-
-  test('js instantiation : new Array()', () {
-    final a = new JsObject(context['Array']);
-    expect(a, isNotNull);
-    expect(a['length'], equals(0));
-
-    a.callMethod('push', ["value 1"]);
-    expect(a['length'], equals(1));
-    expect(a[0], equals("value 1"));
-
-    a.callMethod('pop');
-    expect(a['length'], equals(0));
-  });
-
-  test('js instantiation : new Date()', () {
-    final a = new JsObject(context['Date']);
-    expect(a.callMethod('getTime'), isNotNull);
-  });
-
-  test('js instantiation : new Date(12345678)', () {
-    final a = new JsObject(context['Date'], [12345678]);
-    expect(a.callMethod('getTime'), equals(12345678));
-  });
-
-  test('js instantiation : new Date("December 17, 1995 03:24:00 GMT")',
-      () {
-    final a = new JsObject(context['Date'],
-                           ["December 17, 1995 03:24:00 GMT"]);
-    expect(a.callMethod('getTime'), equals(819170640000));
-  });
-
-  test('js instantiation : new Date(1995,11,17)', () {
-    // Note: JS Date counts months from 0 while Dart counts from 1.
-    final a = new JsObject(context['Date'], [1995, 11, 17]);
-    final b = new DateTime(1995, 12, 17);
-    expect(a.callMethod('getTime'), equals(b.millisecondsSinceEpoch));
-  });
-
-  test('js instantiation : new Date(1995,11,17,3,24,0)', () {
-    // Note: JS Date counts months from 0 while Dart counts from 1.
-    final a = new JsObject(context['Date'],
-                                       [1995, 11, 17, 3, 24, 0]);
-    final b = new DateTime(1995, 12, 17, 3, 24, 0);
-    expect(a.callMethod('getTime'), equals(b.millisecondsSinceEpoch));
-  });
-
-  test('js instantiation : new Object()', () {
-    final a = new JsObject(context['Object']);
-    expect(a, isNotNull);
-
-    a['attr'] = "value";
-    expect(a['attr'], equals("value"));
-  });
-
-  test(r'js instantiation : new RegExp("^\w+$")', () {
-    final a = new JsObject(context['RegExp'], [r'^\w+$']);
-    expect(a, isNotNull);
-    expect(a.callMethod('test', ['true']), isTrue);
-    expect(a.callMethod('test', [' false']), isFalse);
-  });
-
-  test('js instantiation via map notation : new Array()', () {
-    final a = new JsObject(context['Array']);
-    expect(a, isNotNull);
-    expect(a['length'], equals(0));
-
-    a['push'].apply(a, ["value 1"]);
-    expect(a['length'], equals(1));
-    expect(a[0], equals("value 1"));
-
-    a['pop'].apply(a);
-    expect(a['length'], equals(0));
-  });
-
-  test('js instantiation via map notation : new Date()', () {
-    final a = new JsObject(context['Date']);
-    expect(a['getTime'].apply(a), isNotNull);
-  });
-
-  test('js instantiation : typed array', () {
-    if (Platform.supportsTypedData) {
-      final codeUnits = "test".codeUnits;
-      final buf = new JsObject(context['ArrayBuffer'], [codeUnits.length]);
-      final bufView = new JsObject(context['Uint8Array'], [buf]);
-      for (var i = 0; i < codeUnits.length; i++) {
-        bufView[i] = codeUnits[i];
-      }
-    }
-  });
-
-  test('js instantiation : >10 parameters', () {
-    final o = new JsObject(context['Baz'], [1,2,3,4,5,6,7,8,9,10,11]);
-    for (var i = 1; i <= 11; i++) {
-      expect(o["f$i"], i);
-    }
-    expect(o['constructor'], same(context['Baz']));
-  });
-
-  test('write global field', () {
-    context['y'] = 42;
-    expect(context['y'], equals(42));
-  });
-
-  test('get JS JsFunction', () {
-    var razzle = context['razzle'];
-    expect(razzle.apply(context), equals(42));
-  });
-
-  test('call JS function', () {
-    expect(context.callMethod('razzle'), equals(42));
-    expect(() => context.callMethod('dazzle'), throwsA(isNoSuchMethodError));
-  });
-
-  test('call JS function via map notation', () {
-    expect(context['razzle'].apply(context), equals(42));
-    expect(() => context['dazzle'].apply(context),
-        throwsA(isNoSuchMethodError));
-  });
-
-  test('call JS function with varargs', () {
-    expect(context.callMethod('varArgs', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]),
-      equals(55));
-  });
-
-  test('allocate JS object', () {
-    var foo = new JsObject(context['Foo'], [42]);
-    expect(foo['a'], equals(42));
-    expect(foo.callMethod('bar'), equals(42));
-    expect(() => foo.callMethod('baz'), throwsA(isNoSuchMethodError));
-  });
-
-  test('call toString()', () {
-    var foo = new JsObject(context['Foo'], [42]);
-    expect(foo.toString(), equals("I'm a Foo a=42"));
-    var container = context['container'];
-    expect(container.toString(), equals("[object Object]"));
-  });
-
-  test('allocate simple JS array', () {
-    final list = [1, 2, 3, 4, 5, 6, 7, 8];
-    var array = jsify(list);
-    expect(context.callMethod('isArray', [array]), isTrue);
-    expect(array['length'], equals(list.length));
-    for (var i = 0; i < list.length ; i++) {
-      expect(array[i], equals(list[i]));
-    }
-  });
-
-  test('allocate JS array with iterable', () {
-    final set = new Set.from([1, 2, 3, 4, 5, 6, 7, 8]);
-    var array = jsify(set);
-    expect(context.callMethod('isArray', [array]), isTrue);
-    expect(array['length'], equals(set.length));
-    for (var i = 0; i < array['length'] ; i++) {
-      expect(set.contains(array[i]), isTrue);
-    }
-  });
-
-  test('allocate simple JS map', () {
-    var map = {'a': 1, 'b': 2, 'c': 3};
-    var jsMap = jsify(map);
-    expect(!context.callMethod('isArray', [jsMap]), isTrue);
-    for (final key in map.keys) {
-      expect(context.callMethod('checkMap', [jsMap, key, map[key]]), isTrue);
-    }
-  });
-
-  test('allocate complex JS object', () {
-    final object =
-      {
-        'a': [1, [2, 3]],
-        'b': {
-          'c': 3,
-          'd': new JsObject(context['Foo'], [42])
-        },
-        'e': null
-      };
-    var jsObject = jsify(object);
-    expect(jsObject['a'][0], equals(object['a'][0]));
-    expect(jsObject['a'][1][0], equals(object['a'][1][0]));
-    expect(jsObject['a'][1][1], equals(object['a'][1][1]));
-    expect(jsObject['b']['c'], equals(object['b']['c']));
-    expect(jsObject['b']['d'], equals(object['b']['d']));
-    expect(jsObject['b']['d'].callMethod('bar'), equals(42));
-    expect(jsObject['e'], isNull);
-  });
-
-  test('invoke Dart callback from JS', () {
-    expect(() => context.callMethod('invokeCallback'), throws);
-
-    context['callback'] = new Callback(() => 42);
-    expect(context.callMethod('invokeCallback'), equals(42));
-
-    context.deleteProperty('callback');
-    expect(() => context.callMethod('invokeCallback'), throws);
-
-    context['callback'] = () => 42;
-    expect(context.callMethod('invokeCallback'), equals(42));
-
-    context.deleteProperty('callback');
-  });
-
-  test('callback as parameter', () {
-    expect(context.callMethod('getTypeOf', [context['razzle']]),
-        equals("function"));
-  });
-
-  test('invoke Dart callback from JS with this', () {
-    final constructor = new Callback.withThis(($this, arg1) {
-      $this['a'] = 42;
-      $this['b'] = jsify(["a", arg1]);
-    });
-    var o = new JsObject(constructor, ["b"]);
-    expect(o['a'], equals(42));
-    expect(o['b'][0], equals("a"));
-    expect(o['b'][1], equals("b"));
-  });
-
-  test('invoke Dart callback from JS with 11 parameters', () {
-    context['callbackWith11params'] = new Callback((p1, p2, p3, p4, p5, p6, p7,
-        p8, p9, p10, p11) => '$p1$p2$p3$p4$p5$p6$p7$p8$p9$p10$p11');
-    expect(context.callMethod('invokeCallbackWith11params'),
-        equals('1234567891011'));
-  });
-
-  test('return a JS proxy to JavaScript', () {
-    var result = context.callMethod('testJsMap', [() => jsify({'value': 42})]);
-    expect(result, 42);
-  });
-
-  test('test instanceof', () {
-    var foo = new JsObject(context['Foo'], [1]);
-    expect(foo.instanceof(context['Foo']), isTrue);
-    expect(foo.instanceof(context['Object']), isTrue);
-    expect(foo.instanceof(context['String']), isFalse);
-  });
-
-  test('test deleteProperty', () {
-    var object = jsify({});
-    object['a'] = 1;
-    expect(context['Object'].callMethod('keys', [object])['length'], 1);
-    expect(context['Object'].callMethod('keys', [object])[0], "a");
-    object.deleteProperty("a");
-    expect(context['Object'].callMethod('keys', [object])['length'], 0);
-  });
-
-  test('test hasProperty', () {
-    var object = jsify({});
-    object['a'] = 1;
-    expect(object.hasProperty('a'), isTrue);
-    expect(object.hasProperty('b'), isFalse);
-  });
-
-  test('test index get and set', () {
-    final myArray = context['myArray'];
-    expect(myArray['length'], equals(1));
-    expect(myArray[0], equals("value1"));
-    myArray[0] = "value2";
-    expect(myArray['length'], equals(1));
-    expect(myArray[0], equals("value2"));
-
-    final foo = new JsObject(context['Foo'], [1]);
-    foo["getAge"] = () => 10;
-    expect(foo.callMethod('getAge'), equals(10));
-  });
-
-  test('access a property of a function', () {
-    expect(context.callMethod('Bar'), "ret_value");
-    expect(context['Bar']['foo'], "property_value");
-  });
-
-  test('usage of Serializable', () {
+  group('context', () {
+
+    test('read global field', () {
+      expect(context['x'], equals(42));
+      expect(context['y'], isNull);
+    });
+
+    test('read global field with underscore', () {
+      expect(context['_x'], equals(123));
+      expect(context['y'], isNull);
+    });
+
+    test('write global field', () {
+      context['y'] = 42;
+      expect(context['y'], equals(42));
+    });
+
+  });
+
+  group('new JsObject()', () {
+
+    test('allocate JS object', () {
+      var foo = new JsObject(context['Foo'], [42]);
+      expect(foo['a'], equals(42));
+      expect(foo.callMethod('bar'), equals(42));
+      expect(() => foo.callMethod('baz'), throwsA(isNoSuchMethodError));
+    });
+
+    test('new Foo()', () {
+      final Foo2 = context['container']['Foo'];
+      final foo = new JsObject(Foo2, [42]);
+      expect(foo['a'], 42);
+      expect(Foo2['b'], 38);
+    });
+
+    test('new Array()', () {
+      final a = new JsObject(context['Array']);
+      expect(a, isNotNull);
+      expect(a['length'], equals(0));
+
+      a.callMethod('push', ["value 1"]);
+      expect(a['length'], equals(1));
+      expect(a[0], equals("value 1"));
+
+      a.callMethod('pop');
+      expect(a['length'], equals(0));
+    });
+
+    test('new Date()', () {
+      final a = new JsObject(context['Date']);
+      expect(a.callMethod('getTime'), isNotNull);
+    });
+
+    test('new Date(12345678)', () {
+      final a = new JsObject(context['Date'], [12345678]);
+      expect(a.callMethod('getTime'), equals(12345678));
+    });
+
+    test('new Date("December 17, 1995 03:24:00 GMT")',
+        () {
+      final a = new JsObject(context['Date'],
+                             ["December 17, 1995 03:24:00 GMT"]);
+      expect(a.callMethod('getTime'), equals(819170640000));
+    });
+
+    test('new Date(1995,11,17)', () {
+      // Note: JS Date counts months from 0 while Dart counts from 1.
+      final a = new JsObject(context['Date'], [1995, 11, 17]);
+      final b = new DateTime(1995, 12, 17);
+      expect(a.callMethod('getTime'), equals(b.millisecondsSinceEpoch));
+    });
+
+    test('new Date(1995,11,17,3,24,0)', () {
+      // Note: JS Date counts months from 0 while Dart counts from 1.
+      final a = new JsObject(context['Date'],
+                                         [1995, 11, 17, 3, 24, 0]);
+      final b = new DateTime(1995, 12, 17, 3, 24, 0);
+      expect(a.callMethod('getTime'), equals(b.millisecondsSinceEpoch));
+    });
+
+    test('new Object()', () {
+      final a = new JsObject(context['Object']);
+      expect(a, isNotNull);
+
+      a['attr'] = "value";
+      expect(a['attr'], equals("value"));
+    });
+
+    test(r'new RegExp("^\w+$")', () {
+      final a = new JsObject(context['RegExp'], [r'^\w+$']);
+      expect(a, isNotNull);
+      expect(a.callMethod('test', ['true']), isTrue);
+      expect(a.callMethod('test', [' false']), isFalse);
+    });
+
+    test('js instantiation via map notation : new Array()', () {
+      final a = new JsObject(context['Array']);
+      expect(a, isNotNull);
+      expect(a['length'], equals(0));
+
+      a['push'].apply(a, ["value 1"]);
+      expect(a['length'], equals(1));
+      expect(a[0], equals("value 1"));
+
+      a['pop'].apply(a);
+      expect(a['length'], equals(0));
+    });
+
+    test('js instantiation via map notation : new Date()', () {
+      final a = new JsObject(context['Date']);
+      expect(a['getTime'].apply(a), isNotNull);
+    });
+
+    test('typed array', () {
+      if (Platform.supportsTypedData) {
+        final codeUnits = "test".codeUnits;
+        final buf = new JsObject(context['ArrayBuffer'], [codeUnits.length]);
+        final bufView = new JsObject(context['Uint8Array'], [buf]);
+        for (var i = 0; i < codeUnits.length; i++) {
+          bufView[i] = codeUnits[i];
+        }
+      }
+    });
+
+    test('>10 parameters', () {
+      final o = new JsObject(context['Baz'], [1,2,3,4,5,6,7,8,9,10,11]);
+      for (var i = 1; i <= 11; i++) {
+        expect(o["f$i"], i);
+      }
+      expect(o['constructor'], same(context['Baz']));
+    });
+  });
+
+  group('JsFunction', () {
+
+    test('get JS JsFunction', () {
+      var razzle = context['razzle'];
+      expect(razzle.apply(context), equals(42));
+    });
+
+    test('call JS function', () {
+      expect(context.callMethod('razzle'), equals(42));
+      expect(() => context.callMethod('dazzle'), throwsA(isNoSuchMethodError));
+    });
+
+    test('call JS function via map notation', () {
+      expect(context['razzle'].apply(context), equals(42));
+      expect(() => context['dazzle'].apply(context),
+          throwsA(isNoSuchMethodError));
+    });
+
+    test('call JS function with varargs', () {
+      expect(context.callMethod('varArgs', [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]),
+        equals(55));
+    });
+
+    test('access a property of a function', () {
+      expect(context.callMethod('Bar'), "ret_value");
+      expect(context['Bar']['foo'], "property_value");
+    });
+
+  });
+
+  group('Dart callback', () {
+    test('invoke Dart callback from JS', () {
+      expect(() => context.callMethod('invokeCallback'), throws);
+
+      // context['callback'] = new Callback(() => 42);
+      // expect(context.callMethod('invokeCallback'), equals(42));
+
+      // context.deleteProperty('callback');
+      // expect(() => context.callMethod('invokeCallback'), throws);
+
+      context['callback'] = () => 42;
+      expect(context.callMethod('invokeCallback'), equals(42));
+
+      context.deleteProperty('callback');
+    });
+
+    test('callback as parameter', () {
+      expect(context.callMethod('getTypeOf', [context['razzle']]),
+          equals("function"));
+    });
+
+    test('invoke Dart callback from JS with this', () {
+      // A JavaScript constructor function implemented in Dart which
+      // uses 'this'
+      final constructor = new JsFunction.withThis(($this, arg1) {
+        var t = $this;
+        $this['a'] = 42;
+      });
+      var o = new JsObject(constructor, ["b"]);
+      expect(o['a'], equals(42));
+    });
+
+    test('invoke Dart callback from JS with 11 parameters', () {
+      context['callbackWith11params'] = (p1, p2, p3, p4, p5, p6, p7,
+          p8, p9, p10, p11) => '$p1$p2$p3$p4$p5$p6$p7$p8$p9$p10$p11';
+      expect(context.callMethod('invokeCallbackWith11params'),
+          equals('1234567891011'));
+    });
+
+    test('return a JS proxy to JavaScript', () {
+      var result = context.callMethod('testJsMap', [() => new JsObject.jsify({'value': 42})]);
+      expect(result, 42);
+    });
+
+  });
+
+  group('new JsObject.jsify', () {
+
+    test('allocate simple JS array', () {
+      final list = [1, 2, 3, 4, 5, 6, 7, 8];
+      var array = new JsObject.jsify(list);
+      expect(context.callMethod('isArray', [array]), isTrue);
+      expect(array['length'], equals(list.length));
+      for (var i = 0; i < list.length ; i++) {
+        expect(array[i], equals(list[i]));
+      }
+    });
+
+    test('allocate JS array with iterable', () {
+      final set = new Set.from([1, 2, 3, 4, 5, 6, 7, 8]);
+      var array = new JsObject.jsify(set);
+      expect(context.callMethod('isArray', [array]), isTrue);
+      expect(array['length'], equals(set.length));
+      for (var i = 0; i < array['length'] ; i++) {
+        expect(set.contains(array[i]), isTrue);
+      }
+    });
+
+    test('allocate simple JS map', () {
+      var map = {'a': 1, 'b': 2, 'c': 3};
+      var jsMap = new JsObject.jsify(map);
+      expect(!context.callMethod('isArray', [jsMap]), isTrue);
+      for (final key in map.keys) {
+        expect(context.callMethod('checkMap', [jsMap, key, map[key]]), isTrue);
+      }
+    });
+
+    test('allocate complex JS object', () {
+      final object =
+        {
+          'a': [1, [2, 3]],
+          'b': {
+            'c': 3,
+            'd': new JsObject(context['Foo'], [42])
+          },
+          'e': null
+        };
+      var jsObject = new JsObject.jsify(object);
+      expect(jsObject['a'][0], equals(object['a'][0]));
+      expect(jsObject['a'][1][0], equals(object['a'][1][0]));
+      expect(jsObject['a'][1][1], equals(object['a'][1][1]));
+      expect(jsObject['b']['c'], equals(object['b']['c']));
+      expect(jsObject['b']['d'], equals(object['b']['d']));
+      expect(jsObject['b']['d'].callMethod('bar'), equals(42));
+      expect(jsObject['e'], isNull);
+    });
+
+  });
+
+  group('JsObject methods', () {
+
+    test('hashCode and operator==(other)', () {
+      final o1 = context['Object'];
+      final o2 = context['Object'];
+      expect(o1 == o2, isTrue);
+      expect(o1.hashCode == o2.hashCode, isTrue);
+      final d = context['document'];
+      expect(o1 == d, isFalse);
+    });
+
+    test('toString()', () {
+      var foo = new JsObject(context['Foo'], [42]);
+      expect(foo.toString(), equals("I'm a Foo a=42"));
+      var container = context['container'];
+      expect(container.toString(), equals("[object Object]"));
+    });
+
+    test('instanceof', () {
+      var foo = new JsObject(context['Foo'], [1]);
+      expect(foo.instanceof(context['Foo']), isTrue);
+      expect(foo.instanceof(context['Object']), isTrue);
+      expect(foo.instanceof(context['String']), isFalse);
+    });
+
+    test('deleteProperty', () {
+      var object = new JsObject.jsify({});
+      object['a'] = 1;
+      expect(context['Object'].callMethod('keys', [object])['length'], 1);
+      expect(context['Object'].callMethod('keys', [object])[0], "a");
+      object.deleteProperty("a");
+      expect(context['Object'].callMethod('keys', [object])['length'], 0);
+    });
+
+    test('hasProperty', () {
+      var object = new JsObject.jsify({});
+      object['a'] = 1;
+      expect(object.hasProperty('a'), isTrue);
+      expect(object.hasProperty('b'), isFalse);
+    });
+
+    test('index get and set', () {
+      final myArray = context['myArray'];
+      expect(myArray['length'], equals(1));
+      expect(myArray[0], equals("value1"));
+      myArray[0] = "value2";
+      expect(myArray['length'], equals(1));
+      expect(myArray[0], equals("value2"));
+
+      final foo = new JsObject(context['Foo'], [1]);
+      foo["getAge"] = () => 10;
+      expect(foo.callMethod('getAge'), equals(10));
+    });
+
+  });
+
+  test('Serializable', () {
     final red = Color.RED;
     context['color'] = red;
     expect(context['color'], equals(red._value));
   });
 }