* `streamId`.
   *
   * @param streamId client-initiated stream ID.  Must be an odd number.
   * @param promisedStreamId server-initiated stream ID.  Must be an even number.
   * @param requestHeaders minimally includes `:method`, `:scheme`, `:authority`, and `:path`.
   */
  @Throws(IOException::class)
  fun pushPromise(
    streamId: Int,
    promisedStreamId: Int,
    requestHeaders: List<Header>,
  ) {

     *
     * @param streamId client-initiated stream ID.  Must be an odd number.
     * @param promisedStreamId server-initiated stream ID.  Must be an even number.
     * @param requestHeaders minimally includes `:method`, `:scheme`, `:authority`, and `:path`.
     */
    @Throws(IOException::class)
    fun pushPromise(
      streamId: Int,
      promisedStreamId: Int,
      requestHeaders: List<Header>,

  }

  fun ensureAllConnectionsReleased() {
    testClient?.let {
      val connectionPool = it.connectionPool

      connectionPool.evictAll()
      if (connectionPool.connectionCount() > 0) {
        // Minimise test flakiness due to possible race conditions with connections closing.
        // Some number of tests will report here, but not fail due to this delay.
        println("Delaying to avoid flakes")
        Thread.sleep(500L)