code: function encodeRFC5987 (str) {
    return encodeURIComponent(str)
      // Note that although RFC3986 reserves "!", RFC5987 does not,
      // so we do not need to escape it
      .replace(/['()]/g, escape) // i.e., %27 %28 %29
      .replace(/\*/g, '%2A')
      // The following are not required for percent-encoding per RFC5987,
      // so we can allow for a little better readability over the wire: |`^
      .replace(/%(?:7C|60|5E)/g, unescape)
  }
docs: From https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent