code: function rejectHandler(reject, error, removeFolders) {
    logger.warn(error);
    Promise.all(removeFolders.map(folder => fs.removeAsync(folder)))
      .then(() => {
        reject(error);
      })
      .catch((err) => {
        reject(new Error(`${error.message}\n${err.message}`));
      });
  }
docs: Util Methods