Throwable failure = new Throwable();
    future.setException(failure);
    assertThat(future.tryInternalFastPathGetFailure()).isEqualTo(failure);
  }

  public void testTrustedGetFailure_notCompleted() {
    SettableFuture<String> future = SettableFuture.create();
    assertThat(future.isDone()).isFalse();
    assertThat(future.tryInternalFastPathGetFailure()).isNull();
  }