query = function query(options) {
  var opts = merge$3({}, options);
  var queryparse = qs.parse;

  if (typeof options === 'function') {
    queryparse = options;
    opts = undefined;
  }

  if (opts !== undefined && opts.allowPrototypes === undefined) {
    // back-compat for qs module
    opts.allowPrototypes = true;
  }

  return function query(req, res, next){
    if (!req.query) {
      var val = parseUrl(req).query;
      req.query = queryparse(val, opts);
    }

    next();
  };
}
Normalize the given `type`, for example "html" becomes "text/html".

@param {String} type
@return {Object}
@api private