clientListener.assertOpen()
    val server = serverListener.assertOpen()
    val e = RuntimeException()
    clientListener.setNextEventDelegate(
      object : WebSocketListener() {
        override fun onMessage(
          webSocket: WebSocket,
          text: String,
        ) {
          throw e
        }
      },
    )
    server.send("Hello, WebSockets!")
    clientListener.assertFailure(e)