@Test
  public void empty() throws Exception {
    check(repository.findAll().fetchAll().getUnchecked()).isEmpty();
    check(repository.find(criteria()).fetchAll().getUnchecked()).isEmpty();
  }
This one seems to fail: ageNot(30) should return no result.
mongo/test/org/immutables/mongo/fixture/criteria/PersonCriteriaTest.java