Method _cleanup

lib/socket.ts:773–777

* Makes the socket leave all the rooms it was part of and prevents it from joining any other room * * @private

()

   * @private
   */
  _cleanup() {
    this.leaveAll();
    this.nsp._remove(this);
    this.join = noop;
  }

  /**
   * Produces an `error` packet.