}
    }.start();

    try {
      computingSignal.await();
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }

    map.put(one, two);
    assertSame(two, map.get(one));
    startSignal.countDown();

    try {
      doneSignal.await();
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }

    map.cleanUp(); // force notifications

      client
        .newBuilder()
        .addNetworkInterceptor(
          Interceptor { chain: Interceptor.Chain ->
            try {
              latch.await()
            } catch (e: InterruptedException) {
              throw AssertionError(e)
            }
            chain.proceed(chain.request())
          },
        ).build()
    val call = client.newCall(Request(server.url("/a")))