@Test
  void count() {
    check(Flowable.fromPublisher(create().count()).toList().blockingGet()).isOf(0L);
    check(Flowable.fromPublisher(create("one").count()).toList().blockingGet()).isOf(1L);
    check(Flowable.fromPublisher(create("one", "two").count()).toList().blockingGet()).isOf(2L);
    check(Flowable.fromPublisher(create("one", "two", "three").count()).toList().blockingGet()).isOf(3L);
  }
Check that correct exceptions are thrown by {@link ReactiveFetcher}
criteria/common/test/org/immutables/criteria/repository/reactive/ReactiveFetcherDelegateTest.java