Filter abstract classes when computing candidate classes for custom elements.

tests/html/custom/document_register_basic_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 document_register_basic_test;
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_config.dart';
 import 'dart:html';
 import '../utils.dart';
 
@@ skipping 17 matching lines @@
   static final tag = 'x-baz';
   factory Baz() => new Element.tag(tag);
   Baz.created() : super.created();
 
   get thisIsAlsoACustomClass => true;
 }
 
 class BadB {
 }
 
-class BadE implements HtmlElement {
-  static final tag = 'x-tag-e';
-  factory BadE() => new Element.tag(tag);
+abstract class BadC extends HtmlElement {
+  BadC.created() : super.created();
+}
+
+class BadF implements HtmlElement {
+  static final tag = 'x-tag-f';
+  factory BadF() => new Element.tag(tag);
 }
 
 main() {
   useHtmlConfiguration();
 
   // Adapted from Blink's fast/dom/custom/document-register-basic test.
 
   setUp(() => customElementsReady);
 
   test('Testing document.registerElement() basic behaviors', () {
     document.registerElement(Foo.tag, Foo);
 
     // Cannot register an existing dart:html type.
     expect(() => document.registerElement('x-bad-a', HtmlElement), throws);
 
     // Invalid user type.  Doesn't inherit from HtmlElement.
     expect(() => document.registerElement('x-bad-b', BadB), throws);
 
+    // Cannot register abstract class.
+    expect(() => document.registerElement('x-bad-c', BadC), throws);

[karlklose, 2014/09/09 13:02:22]

You could make this a multitest with label OK and add a comment to the status
file to remove the label when fixing the bug.

[herhut, 2014/09/09 13:33:26]

Just for the record: It seems this is not supported.

+
     // Not a type.
-    expect(() => document.registerElement('x-bad-c', null), throws);
+    expect(() => document.registerElement('x-bad-d', null), throws);
 
     // Cannot register system type.
-    expect(() => document.registerElement('x-bad-d', Object), throws);
+    expect(() => document.registerElement('x-bad-e', Object), throws);
 
     // Must extend HtmlElement, not just implement it.
-    expect(() => document.registerElement(BadE.tag, BadE), throws);
+    expect(() => document.registerElement(BadF.tag, BadF), throws);
 
     // Constructor initiated instantiation
     var createdFoo = new Foo();
     expect(createdFoo.thisIsACustomClass, isTrue);
 
     // Dart type correctness
     expect(createdFoo is HtmlElement, isTrue);
     expect(createdFoo is Foo, isTrue);
     expect(createdFoo.runtimeType, Foo);
 
@@ skipping 55 matching lines @@
     expect(container.firstChild.tagName, "X-BAR");
     expect(container.lastChild is Bar, isTrue);
     expect(container.lastChild.tagName, "X-BAR");
 
     // Constructors shouldn't interfere with each other
     expect((new Foo()).tagName, "X-FOO");
     expect((new Bar()).tagName, "X-BAR");
     expect((new Baz()).tagName, "X-BAZ");
   });
 }