@Test
public void testNonContentedComputation() throws Exception {

    ExtTestSubscriber<String> testSubscriber = new ExtTestSubscriber<>();
    invoker.recompute().subscribe(testSubscriber);
    testScheduler.advanceTimeBy(TASK_DELAY_MS, TimeUnit.MILLISECONDS);
    assertThat(testSubscriber.takeNext()).isEqualTo("Done round 0");
    assertThat(testSubscriber.isUnsubscribed()).isTrue();
    assertThat(invocationCounter.get()).isEqualTo(1);
}