.post(
            object : RequestBody() {
              override fun contentType() = null

              override fun writeTo(sink: BufferedSink) {
                for (i in 0..9) {
                  sink.writeByte(0)
                  sink.flush()
                  sleep(100)
                }
                fail("Expected connection to be closed")
              }
            },

  override fun contentType(): MediaType? = null

  override fun writeTo(sink: BufferedSink) {
    requestBodySinks.add(sink)
  }

  override fun isDuplex(): Boolean = true

  @Throws(InterruptedException::class)
  fun takeSink(): BufferedSink = requestBodySinks.poll(5, SECONDS) ?: throw AssertionError("no sink to take")

  fun assertNoMoreSinks() {
    assertTrue(requestBodySinks.isEmpty())
  }

  /**
   * Sends a stream of data from the {@code from} object into the sink {@code into}. There is no
   * requirement that this data be complete enough to fully reconstitute the object later.
   *
   * @since 12.0 (in Guava 11.0, {@code PrimitiveSink} was named {@code Sink})
   */
  void funnel(@ParametricNullness T from, PrimitiveSink into);

    )
    val asyncRequestBody: RequestBody =
      object : RequestBody() {
        override fun contentType(): MediaType? = null

        override fun writeTo(sink: BufferedSink) {
          sink.writeUtf8("Hello request!")
          sink.close()
        }

        override fun isDuplex(): Boolean = true
      }
    val request =
      request()
        .post(asyncRequestBody)

      mutableByteCount -= bytesWritten
    }
  }

  /**
   * Copy [byteCount] bytes from the file at [pos] into `sink`. It is the
   * caller's responsibility to make sure there are sufficient bytes to read: if there aren't this
   * method throws an `EOFException`.
   */
  fun read(
    pos: Long,
    sink: Buffer,
    byteCount: Long,
  ) {
    if (byteCount < 0L) {
      throw IndexOutOfBoundsException()
    }

    val pipe = Pipe(1024)
    val sink = pipe.sink.buffer()
    val relay = edit(file, pipe.source, metadata, 5)
    val future1 = executor.submit(sourceReader(relay.newSource()))
    val future2 = executor.submit(sourceReader(relay.newSource()))
    Thread.sleep(500)
    sink.writeUtf8("abcdefghij")
    Thread.sleep(500)
    sink.writeUtf8("klmnopqrst")
    sink.close()
    assertThat<ByteString>(future1.get())

    val stream = connection.newStream(headerEntries("b", "banana"), true)
    val sink = stream.sink
    sink.write(Buffer().writeUtf8("abcde"), 5)
    stream.writeTimeout().timeout(500, TimeUnit.MILLISECONDS)
    val startNanos = System.nanoTime()
    sink.write(Buffer().writeUtf8("f"), 1)
    assertFailsWith<InterruptedIOException> {
      sink.flush() // This will time out waiting on the write window.
    }

      override fun contentType(): MediaType? = "text/plain".toMediaTypeOrNull()

      @Throws(IOException::class)
      override fun writeTo(sink: BufferedSink) {
        try {
          sink.writeUtf8("abc")
          sink.flush()
          Thread.sleep(sleepMillis.toLong())
          sink.writeUtf8("def")
        } catch (e: InterruptedException) {
          throw InterruptedIOException()
        }
      }
    }

   *
   * @param sink the output byte array
   * @param offset the offset into the array at which to start writing
   * @param value the value to write
   */
  static void store64(byte[] sink, int offset, long value) {
    // We don't want to assert in production code.
    assert offset >= 0 && offset + 8 <= sink.length;
    // Delegates to the fast (unsafe)version or the fallback.

    s: String,
    responseSent: CountDownLatch = CountDownLatch(1),
  ) = apply {
    actions += { stream ->
      stream.sink.writeUtf8(s)
      stream.sink.flush()
      responseSent.countDown()
    }
  }

  fun exhaustResponse() =
    apply {
      actions += { stream -> stream.sink.close() }
    }

  fun sleep(
    duration: Long,
    unit: TimeUnit,
  ) = apply {