@Test
public void testAddTagToTeam() throws Exception {

    TeamTagMap ttm = new TeamTagMap();
    TeamTagMap ttmAfter = ttm.addTagToTeam("ABCDEFF012", 0);
    assertThat(ttm.tagToTeam("ABCDEFF012"), equalTo(Optional.empty()));
    assertThat(ttmAfter.getTagToTeam(), hasEntry(new TagId("ABCDEFF012"), 0));
    assertThat(ttmAfter.tagToTeam("ABCDEFF012"), equalTo(Optional.of(0)));
}