stylelint-bundle-worker.js
function toRegex(glob, options) {
  // clone options to prevent  mutating the original object
  var opts = Object.create(options || {});
  var flags = opts.flags || '';
  if (opts.nocase && flags.indexOf('i') === -1) {
    flags += 'i';
  }

  var parsed = expand(glob, opts);

  // pass in tokens to avoid parsing more than once
  opts.negated = opts.negated || parsed.negated;
  opts.negate = opts.negated;
  glob = wrapGlob(parsed.pattern, opts);
  var re;

  try {
    re = new RegExp(glob, flags);
    return re;
  } catch (err) {
    err.reason = 'micromatch invalid regex: (' + re + ')';
    if (opts.strict) throw new SyntaxError(err);
  }

  // we're only here if a bad pattern was used and the user
  // passed `options.silent`, so match nothing
  return /$^/;
}
function toRegex(glob, options) {
  // clone options to prevent  mutating the original object
  var opts = Object.create(options || {});
  var flags = opts.flags || '';
  if (opts.nocase && flags.indexOf('i') === -1) {
    flags += 'i';
  }

  var parsed = expand(glob, opts);

  // pass in tokens to avoid parsing more than once
  opts.negated = opts.negated || parsed.negated;
  opts.negate = opts.negated;
  glob = wrapGlob(parsed.pattern, opts);
  var re;

  try {
    re = new RegExp(glob, flags);
    return re;
  } catch (err) {
    err.reason = 'micromatch invalid regex: (' + re + ')';
    if (opts.strict) throw new SyntaxError(err);
  }

  // we're only here if a bad pattern was used and the user
  // passed `options.silent`, so match nothing
  return /$^/;
}
Create and cache a regular expression for matching
file paths.

If the leading character in the `glob` is `!`, a negation
regex is returned.

@param  {String} `glob`
@param  {Object} `options`
@return {RegExp}