@Test
public void testGetUserPhotoURLs() {

    String url1 = "http://u1.com";
    String url2 = "http://u1.com";
    User user1 = new User("u1", "u1@email.com", false, false, false, "name", "mu1", url1,
                          DateTime.now(), DateTime.now(), null, null, null, null);
    User user2 = new User("u2", "u2@email.com", false, false, false, "name", "mu2", url2,
                          DateTime.now(), DateTime.now(), null, null, null, null);
    Map<String, User> users = ImmutableMap.of("id1", user1, "id2", user2);
    when(chatApiDao.getUsers()).thenReturn(users);
    Map<String, String> expectedResult = ImmutableMap.of(user1.getMentionName(), url1,
                                                         user2.getMentionName(), url2);
    Map<String, String> result = underTest.getUserPhotoURLs();
    assertEquals(expectedResult, result);
}