processWorkerReply(
  metadata: WorkerMetadata,
  fileMetadata: FileMetaData,
) {
  fileMetadata[H.VISITED] = 1;

  const metadataId = metadata.id;

  if (metadataId != null) {
    fileMetadata[H.ID] = metadataId;
  }

  fileMetadata[H.DEPENDENCIES] = metadata.dependencies
    ? metadata.dependencies.join(H.DEPENDENCY_DELIM)
    : '';

  if (metadata.sha1 != null) {
    fileMetadata[H.SHA1] = metadata.sha1;
  }

  return metadata.content;
}
Creates workers or parses files and extracts metadata in-process.