BiMap<String, Integer> bimap = ImmutableBiMap.copyOf(ImmutableMap.of("one", 1, "two", 2));
    assertThrows(UnsupportedOperationException.class, () -> bimap.forcePut("three", 3));
  }

  public void testKeySet() {
    ImmutableBiMap<String, Integer> bimap =
        ImmutableBiMap.copyOf(ImmutableMap.of("one", 1, "two", 2, "three", 3, "four", 4));
    Set<String> keys = bimap.keySet();

    assertNotInstantiable(new TypeToken<ArrayList<EmptyEnum>>() {});
  }

  public void testLinkedList() {
    assertFreshInstance(new TypeToken<LinkedList<String>>() {});
  }

  public void testSet() {
    assertFreshInstance(new TypeToken<Set<String>>() {});
    assertNotInstantiable(new TypeToken<Set<EmptyEnum>>() {});
  }

  public void testHashSet() {

  public void testToSortedList_withDuplicates() {
    assertEquals(
        Lists.newArrayList(4, 3, 1, 1),
        fluent(1, 4, 1, 3).toSortedList(Ordering.<Integer>natural().reverse()));
  }

  public void testToSet() {
    assertThat(fluent(1, 2, 3, 4).toSet()).containsExactly(1, 2, 3, 4).inOrder();
  }

  public void testToSet_removeDuplicates() {
    assertThat(fluent(1, 2, 1, 2).toSet()).containsExactly(1, 2).inOrder();