@Test
@SuppressWarnings( "unchecked" )
public void testBuildUseCaseObservableReturnCorrectResult() {

    TestSubscriber<Integer> testSubscriber = new TestSubscriber<>();
    TestScheduler testScheduler = new TestScheduler();
    given( mockPostExecutionThread.getScheduler() ).willReturn( testScheduler );
    useCase.execute( testSubscriber );
    assertThat( testSubscriber.getOnNextEvents().size(), is( 0 ) );
}