.body("def")
        .throttleBody(1, 750, TimeUnit.MILLISECONDS)
        .build(),
    )
    val call = client.newCall(Request(server.url("/a")))
    val executor = Executors.newSingleThreadExecutor()
    val result = executor.submit<Response?> { call.execute() }
    Thread.sleep(100) // wait for it to go in flight.
    call.cancel()
    assertFailsWith<IOException> {
      result.get()!!.body.bytes()