anchor.diff:  
     @override
     Future<List<DiagramMetadata>> get diagrams async => <DiagramMetadata>[
  -    const CustomListItemDiagram('custom_list_item'),
  -  ];
  +        const CustomListItemDiagram('custom_list_item'),
  +      ];
   
     @override
     Future<File> generateDiagram(DiagramMetadata diagram) async {
  
positive.code:       child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: <Widget>[
            Text(title,
              style: const TextStyle(
                fontWeight: FontWeight.w500,
                fontSize: 14.0,
              ),
            ),
            const Padding(padding: EdgeInsets.symmetric(vertical: 2.0)),
            Text(user, style: const TextStyle(fontSize: 10.0)),
            const Padding(padding: EdgeInsets.symmetric(vertical: 1.0)),
            Text('$viewCount views', style: const TextStyle(fontSize: 10.0),
            ),
          ],
        ),
  
negative.code:             CustomListItem(
                user: 'Flutter',
                viewCount: 999000,
                thumbnail: Icon(
                  Icons.videocam,
                  size: 80,
                  color: Colors.blueGrey,
                ),
                title: 'The Flutter YouTube Channel',
              ),
              CustomListItem(
                user: 'Dash',
                viewCount: 884000,
                thumbnail:
                  Icon(
                    Icons.flight_takeoff,
                    size: 80,
                    color: Colors.blueGrey,
                  ),
                title: 'Announcing Flutter 1.0',
              ),
            ],
  