return connect
  }

  /**
   * Returns the connection already attached to the call if it's eligible for a new exchange.
   *
   * If the call's connection exists and is eligible for another exchange, it is returned. If it
   * exists but cannot be used for another exchange, it is closed and this returns null.
   */
  private fun planReuseCallConnection(): ReusePlan? {
    // This may be mutated by releaseConnectionNoEvents()!

   *     Corresponds to `FLAG_FIN`.
   * @param flushHeaders true to force flush the response headers. This should be true unless the
   *     response body exists and will be written immediately.
   */
  @Throws(IOException::class)
  fun writeHeaders(
    responseHeaders: List<Header>,
    outFinished: Boolean,
    flushHeaders: Boolean,
  ) {

    assertThat(pool.closeConnections(149L)).isEqualTo(1L)
    assertThat(pool.connectionCount()).isEqualTo(1)
    assertThat(c1.socket().isClosed).isFalse()

    // Running at time 150, the pool evicts.
    assertThat(pool.closeConnections(150L)).isEqualTo(0)
    assertThat(pool.connectionCount()).isEqualTo(0)
    assertThat(c1.socket().isClosed).isTrue()