anchor.diff:          '<li class="qux lassy">'
           '</ul>');
   
  -  Set<String> makeClassSet() => makeElementWithClasses().classes;
  +Element listElement;
  +
  +ElementList<Element> listElementSetup() {
  +  listElement = makeListElement();
  +  document.documentElement.children.add(listElement);
  +  return document.querySelectorAll('li');
  +}
  +
  +void listElementTearDown() {
  +  if (listElement != null) {
  +    document.documentElement.children.remove(listElement);
  +    listElement = null;
  +  }
  +}
  +
  +/// Returns a canonical string for Set<String> and lists of Element's classes.
  +String view(var e) {
  +  if (e is Set) return '${e.toList()..sort()}';
  +  if (e is Element) return view(e.classes);
  +  if (e is Iterable) return '${e.map(view).toList()}';
  +  throw new ArgumentError('Cannot make canonical view string for: $e}');
  +}
  +
  +main() {
  +  useHtmlConfiguration();
   
     Set<String> extractClasses(Element el) {
       final match = new RegExp('class="([^"]+)"').firstMatch(el.outerHtml);
       return new LinkedHashSet.from(match[1].split(' '));
     }
   
  -  /// Returns a canonical string for Set<String> and lists of Element's classes.
  -  String view(var e) {
  -    if (e is Set) return '${e.toList()..sort()}';
  -    if (e is Element) return view(e.classes);
  -    if (e is Iterable) return '${e.map(view).toList()}';
  -    throw new ArgumentError('Cannot make canonical view string for: $e}');
  -  }
   
     test('affects the "class" attribute', () {
       final el = makeElementWithClasses();
  
positive.code:     expect(classes, orderedEquals(['foo', 'bar', 'aardvark', 'baz']));
    });
  
  
    Element listElement;
  
    ElementList<Element> listElementSetup() {
      listElement = makeListElement();
      document.documentElement.children.add(listElement);
      return document.querySelectorAll('li');
    }
  
    tearDown(() {
      if (listElement != null) {
        document.documentElement.children.remove(listElement);
        listElement = null;
      }
    });
  
    test('list_view', () {
      // Test that the 'view' helper function is behaving.
  
negative.code: import 'dart:collection';
  import 'dart:html';
  
  Element makeElement() => new Element.tag('div');
  
  Element makeElementWithClasses() =>
      new Element.html('<div class="foo bar baz"></div>');
  
  Set<String> makeClassSet() => makeElementWithClasses().classes;
  
  Element makeListElement() =>
      new Element.html('<ul class="foo bar baz">'
          '<li class="quux qux">'
          '<li class="meta">'
  