anchor.diff:        expect(actual.toString(), expected.toString());
       });
     });
  +
     group('examples', () {
       test('extract non-empty text', () {
         final texts = parseEvents(bookstoreXml)
  
positive.code:           .where((text) => text.isNotEmpty);
        expect(texts, ['Harry Potter', '29.99', 'Learning XML', '39.95']);
      });
      test('find specific attribute', () {
        final maxExclusive = parseEvents(shiporderXsd)
            .whereType<XmlStartElementEvent>()
            .singleWhere((event) => event.name == 'xsd:maxExclusive')
  
negative.code: 
  import 'assertions.dart';
  import 'examples.dart';
  
  void assertComplete(Iterator<XmlEvent> iterator) {
    for (var i = 0; i < 2; i++) {
  