@Test
public void testGetTotalMentionsForEmoji() {

    Interval timeInterval = new Interval(mentionDate, mentionDate.plusHours(3));
    // Make sure that 0 is returned when nothing is found
    assertEquals(0, underTest.getTotalMentionsForEmoji("unknownemoji",
                                                       timeInterval,
                                                       ImmutableList.of(),
                                                       ImmutableList.of(),
                                                       true));
    // make sure that the sums are correct for a bunch of different queries
    int result = underTest.getTotalMentionsForEmoji("e1", timeInterval,
                                                    ImmutableList.of(),
                                                    ImmutableList.of(),
                                                    true);
    assertEquals(3, result);
    result = underTest.getTotalMentionsForEmoji("e1", timeInterval,
                                                ImmutableList.of("room1"),
                                                ImmutableList.of(),
                                                true);
    assertEquals(2, result);
    result = underTest.getTotalMentionsForEmoji("e1", timeInterval,
                                                ImmutableList.of("room1"),
                                                ImmutableList.of("giannis"),
                                                true);
    assertEquals(1, result);
}