stylelint-bundle-worker.js
function brackets(pattern, options) {
  debug('initializing from <%s>', __filename);
  var res = brackets.create(pattern, options);
  return res.output;
}
function brackets(pattern, options) {
  debug('initializing from <%s>', __filename);
  var res = brackets.create(pattern, options);
  return res.output;
}
Parses the given POSIX character class `pattern` and returns a
string that can be used for creating regular expressions for matching.

@param {String} `pattern`
@param {Object} `options`
@return {Object}
@api public