anchor.diff:    static final _BOWER_REGISTRY_INFO_URL_REGEXP =
         new RegExp(_BOWER_REGISTRY_INFO_URL);
   
  +  static const _GIT_TAG = r'refs/tags/(.+)';
  +  static final _GIT_TAG_REGEXP = new RegExp(_GIT_TAG);
  +
     final String name;
     final String fullPath;
     String path;
  
positive.code:     });
    }
  
    Future<List<Map<String, dynamic>>> _fetchTags() {
      return util.downloadFileViaXhr(getTagsUrl()).then((String tagsStr) {
        try {
          return JSON.decode(tagsStr);
        } on FormatException catch (e) {
          return null;
        }
      });
    }
  
    Future<_Resolution> _resolveWith(_Resolution resolution) {
  
negative.code:       }
      }
  
      return _fetchTags().then((List<String> tags) {
        if (tags == null || tags.isEmpty) {
          return _resolveWith(_Unresolved.BAD_OR_MISSING_GITHUB_TAGS);
        }
  