Adding polyfill support for custom elements.

tests/html/custom_elements_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_elements_test;
-import '../../pkg/unittest/lib/unittest.dart';
-import '../../pkg/unittest/lib/html_individual_config.dart';
+import 'dart:async';
 import 'dart:html';
+import 'package:unittest/html_individual_config.dart';
+import 'package:unittest/unittest.dart';
 
 class CustomMixin {
   var mixinMethodCalled;
 
   void mixinMethod() {
     mixinMethodCalled = true;
   }
 }
 
 class CustomType extends HtmlElement with CustomMixin{
   factory CustomType() => null;
   bool onCreatedCalled; // = false;
   void onCreated() {
     onCreatedCalled = true;
     customCreatedCount++;
   }
 
   void invokeMixinMethod() {
     mixinMethod();
   }
 }
 
 int customCreatedCount = 0;
 
 int nextTagId = 0;
 String get nextTag => 'x-type${nextTagId++}';
 
 class NotAnElement {}
 
+loadPolyfills() {
+  if (!document.supportsRegister) {

[Jennifer Messerly, 2013/08/20 19:09:59]

this doesn't need mutation observers?

[blois, 2013/08/20 19:36:56]

It  does, they are included in the file. Per-polyfill scripts probably do not
work well with overlapping dependencies.

+    return HttpRequest.getString('/root_dart/pkg/custom_element/lib/'
+      'custom-elements.debug.js').then((code) {
+      document.head.children.add(new ScriptElement()..text = code);
+    });
+  }
+}
+
 main() {
   useHtmlIndividualConfiguration();
 
+  setUp(loadPolyfills);
+
   group('register', () {
     test('register', () {
       var tag = nextTag;
       document.register(tag, CustomType);
 
       var element = new Element.tag(tag);
       expect(element, isNotNull);
       expect(element is CustomType, isTrue);
       expect(element.onCreatedCalled, isTrue);
     });
@@ skipping 32 matching lines @@
     });
   });
 
   // TODO(vsm): Modify this test once we agree on the proper semantics.
   /*
   group('preregister', () {
 
     test('pre-registration construction', () {
       var tag = nextTag;
       var dom = new Element.html('<div><$tag></$tag></div>');
+
       var preElement = dom.children[0];
       expect(preElement, isNotNull);
       expect(preElement is HtmlElement, isTrue);
       expect(preElement is CustomType, isFalse);
       var firedOnPre = false;
       preElement.onFocus.listen((_) {
         firedOnPre = true;
       });
 
       document.register(tag, CustomType);
+      Platform.upgradeCustomElements(dom);
 
       var postElement = dom.children[0];
       expect(postElement, isNotNull);
       expect(postElement is CustomType, isTrue);
       expect(postElement.onCreatedCalled, isTrue);
 
       // Element from first query remains an UnknownElement.
       expect(preElement is HtmlElement, isTrue);
       expect(preElement.parent, dom);
       expect(dom.children.length, 1);
@@ skipping 53 matching lines @@
     test('can invoke mixin methods', () {
       var tag = nextTag;
       document.register(tag, CustomType);
 
       var element = new Element.tag(tag);
       element.invokeMixinMethod();
       expect(element.mixinMethodCalled, isTrue);
     });
   });
 }