assertThat(map.values() instanceof Set).isFalse();
    assertThat(map.values().removeAll(ImmutableSet.of("bar"))).isTrue();
    assertThat(map).hasSize(1);
  }

  public void testComputeIfAbsent_removalListener() {
    List<RemovalNotification<Object, Object>> notifications = new ArrayList<>();
    RemovalListener<Object, Object> removalListener =
        new RemovalListener<Object, Object>() {
          @Override