anchor.diff:        return null;
       }
     }
  -}
  +
  +  String _getHost() {
  +    final String? host = connectionManager.url;
  +    if (host == null) {
  +      throw APIError.unspecifiedHost;
  +    }
  +    return host;
  +  }
  +}
  
positive.code:     if (connectionManager.state == connection.State.connected) {
        return _httpClient.flatten(path);
      }
      // TODO implement offline flatten
      return [];
    }
  
    Uri _getImageURI(String path) {
  
negative.code:   OfflineClient({required this.connectionManager, required this.mediaCache, required this.collectionCache});
  
    List<dto.CollectionFile> browse(String path) {
      final String host = _getHost();
      final cachedContent = collectionCache.getDirectory(host, path);
      if (cachedContent == null) {
        throw throw APIError.unexpectedCacheMiss;
  