implement dirty checking for @observable objects

pkg/mdv/test/custom_element_bindings_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 custom_element_bindings_test;
 
 import 'dart:async';
 import 'dart:html';
 import 'package:mdv/mdv.dart' as mdv;
 import 'package:observe/observe.dart';
 import 'package:unittest/html_config.dart';
 import 'package:unittest/unittest.dart';
-import 'observe_utils.dart';
+import 'mdv_test_utils.dart';
 
 main() {
   mdv.initialize();
   useHtmlConfiguration();
   group('Custom Element Bindings', customElementBindingsTest);
 }
 
 sym(x) => new Symbol(x);
 
 customElementBindingsTest() {
@@ skipping 14 matching lines @@
     testDiv.append(div);
 
     for (var node in div.queryAll('*')) {
       if (node.isTemplate) TemplateElement.decorate(node);
     }
 
     return div;
   }
 
 
-  test('override bind/unbind/unbindAll', () {
+  observeTest('override bind/unbind/unbindAll', () {
     var element = new MyCustomElement();
     var model = toSymbolMap({'a': new Point(123, 444), 'b': new Monster(100)});
 
     element.bind('my-point', model, 'a');
     element.bind('scary-monster', model, 'b');
 
     expect(element.attributes, isNot(contains('my-point')));
     expect(element.attributes, isNot(contains('scary-monster')));
 
     expect(element.myPoint, model[sym('a')]);
     expect(element.scaryMonster, model[sym('b')]);
 
     model[sym('a')] = null;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.myPoint, null);
     element.unbind('my-point');
 
     model[sym('a')] = new Point(1, 2);
     model[sym('b')] = new Monster(200);
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.scaryMonster, model[sym('b')]);
     expect(element.myPoint, null, reason: 'a was unbound');
 
     element.unbindAll();
     model[sym('b')] = null;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.scaryMonster.health, 200);
   });
 
-  test('override attribute setter', () {
+  observeTest('override attribute setter', () {
     var element = new WithAttrsCustomElement().real;
     var model = toSymbolMap({'a': 1, 'b': 2});
     element.bind('hidden?', model, 'a');
     element.bind('id', model, 'b');
 
     expect(element.attributes, contains('hidden'));
     expect(element.attributes['hidden'], '');
     expect(element.id, '2');
 
     model[sym('a')] = null;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.attributes, isNot(contains('hidden')),
         reason: 'null is false-y');
 
     model[sym('a')] = false;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.attributes, isNot(contains('hidden')));
 
     model[sym('a')] = 'foo';
+    // TODO(jmesserly): this is here to force an ordering between the two
+    // changes. Otherwise the order depends on what order StreamController
+    // chooses to fire the two listeners in.
+    performMicrotaskCheckpoint();
+
     model[sym('b')] = 'x';
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.attributes, contains('hidden'));
     expect(element.attributes['hidden'], '');
     expect(element.id, 'x');
 
     expect(element.xtag.attributes.log, [
       ['remove', 'hidden?'],
       ['[]=', 'hidden', ''],
       ['remove', 'id'],
       ['[]=', 'id', '2'],
       ['remove', 'hidden'],
       ['remove', 'hidden'],
       ['[]=', 'hidden', ''],
       ['[]=', 'id', 'x'],
     ]);
   });
 
-  test('template bind uses overridden custom element bind', () {
+  observeTest('template bind uses overridden custom element bind', () {
 
     var model = toSymbolMap({'a': new Point(123, 444), 'b': new Monster(100)});
 
     var div = createTestHtml('<template bind>'
           '<my-custom-element my-point="{{a}}" scary-monster="{{b}}">'
           '</my-custom-element>'
         '</template>');
 
     mdv.instanceCreated.listen((fragment) {
       for (var e in fragment.queryAll('my-custom-element')) {
         new MyCustomElement.attach(e);
       }
     });
 
     div.query('template').model = model;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
 
     var element = div.nodes[1];
 
     expect(element.xtag is MyCustomElement, true,
         reason: '${element.xtag} should be a MyCustomElement');
 
     expect(element.xtag.myPoint, model[sym('a')]);
     expect(element.xtag.scaryMonster, model[sym('b')]);
 
     expect(element.attributes, isNot(contains('my-point')));
     expect(element.attributes, isNot(contains('scary-monster')));
 
     model[sym('a')] = null;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
     expect(element.xtag.myPoint, null);
 
     div.query('template').model = null;
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
 
     expect(element.parentNode, null, reason: 'element was detached');
 
     model[sym('a')] = new Point(1, 2);
     model[sym('b')] = new Monster(200);
-    deliverChangeRecords();
+    performMicrotaskCheckpoint();
 
     expect(element.xtag.myPoint, null, reason: 'model was unbound');
     expect(element.xtag.scaryMonster.health, 100, reason: 'model was unbound');
   });
 
 }
 
 class Monster {
   int health;
   Monster(this.health);
@@ skipping 111 matching lines @@
   }
 
   void clear() => _map.clear();
   void forEach(void f(K key, V value)) => _map.forEach(f);
   Iterable<K> get keys => _map.keys;
   Iterable<V> get values => _map.values;
   int get length => _map.length;
   bool get isEmpty => _map.isEmpty;
   bool get isNotEmpty => _map.isNotEmpty;
 }