code: function parseOptions(options) {
      var defaultOptions = {
        verbose: false,
        prune: false,
        placeholder: false
      };
      options = options || {};
  
      // Delete sort option if not valid.
      if (options.sort && ['asc', 'desc'].indexOf(options.sort.toLowerCase()) === -1) {
        delete options.sort;
      }
  
      return _.extend(defaultOptions, options);
    }
docs: Parse options.
  
  @param {object} options - options object
  @returns {object}