* be non-null.
   *
   * If the exchange was canceled or timed out, this will wrap [e] in an exception that provides
   * that additional context. Otherwise [e] is returned as-is.
   */
  internal fun messageDone(
    exchange: Exchange,
    requestDone: Boolean = false,
    responseDone: Boolean = false,
    e: IOException?,
  ): IOException? {