docs: function getFileTypeReg(type) {
      var map = [],
          ext = ""; // fis.config.get('project.fileType.' + type);
      if (type === 'text') {
          map = TEXT_FILE_EXTS;
      } else if (type === 'image') {
          map = IMAGE_FILE_EXTS;
      } else {
          xgulp.log.error('invalid file type [%s]', type);
      }
      if (ext && ext.length) {
          if (typeof ext === 'string') {
              ext = ext.split(/\s*,\s*/);
          }
          map = map.concat(ext);
      }
      map = map.join('|');
      return new RegExp('\\.(?:' + map + ')$', 'i');
  }