)
    val call =
      client.newCall(
        Request
          .Builder()
          .url(server.url("/"))
          .post(AsyncRequestBody())
          .build(),
      )
    call.execute().use { response ->
      val requestBody = (call.request().body as AsyncRequestBody?)!!.takeSink()
      requestBody.writeUtf8("request A\n")
      requestBody.flush()
      val responseBody = response.body.source()

    url = server.url("/")
    setLevel(Level.BODY)
    server.enqueue(
      MockResponse
        .Builder()
        .body("Hello response!")
        .build(),
    )
    val asyncRequestBody: RequestBody =
      object : RequestBody() {
        override fun contentType(): MediaType? = null

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