anchor.diff:      testWidgets((WidgetTester tester) {
         tester.pumpWidget(new MarkdownBody(data: ""));
   
  -      List<Element> elements = _listElements(tester);
  -      _expectWidgetTypes(elements, <Type>[MarkdownBody, Column]);
  +      Iterable<Widget> widgets = tester.widgets;
  +      _expectWidgetTypes(widgets, <Type>[MarkdownBody, Column]);
       });
     });
   
  
positive.code:   });
  }
  
  List<Element> _listElements(WidgetTester tester) {
    List<Element> elements = <Element>[];
    tester.walkElements((Element element) {
      elements.add(element);
    });
    return elements;
  }
  
  void _expectWidgetTypes(List<Element> elements, List<Type> types) {
    expect(elements.length, equals(types.length));
    for (int i = 0; i < elements.length; i += 1) {
      Element element = elements[i];
      Type type = types[i];
      if (type == null) continue;
      expect(element.widget.runtimeType, equals(type));
    }
  }
  
  void _expectTextStrings(List<Element> elements, List<String> strings) {
    int currentString = 0;
    for (Element element in elements) {
      Widget widget = element.widget;
      if (widget is RichText) {
        TextSpan span = widget.text;
        String text = _extractTextFromTextSpan(span);
  
negative.code:     testWidgets((WidgetTester tester) {
        tester.pumpWidget(new Markdown(data: "[Link Text](href)"));
  
        RichText textWidget = tester.widgets.firstWhere((Widget widget) => widget is RichText);
        TextSpan span = textWidget.text;
  
        expect(span.children[0].recognizer.runtimeType, equals(TapGestureRecognizer));
  