}

  public Test testsForEmptyList() {
    return ListTestSuiteBuilder.using(
            new TestStringListGenerator() {
              @Override
              public List<String> create(String[] elements) {
                return Collections.emptyList();
              }
            })
        .named("emptyList")
        .withFeatures(CollectionFeature.SERIALIZABLE, CollectionSize.ZERO)

            new TestStringSortedMapGenerator() {
              @Override
              protected SortedMap<String, String> create(Entry<String, String>[] entries) {
                /*
                 * TODO(cpovirk): it would be nice to create an input Map and use
                 * the copy constructor here and in the other tests
                 */

    suite.addTest(
        SortedMultisetTestSuiteBuilder.using(
                new TestStringMultisetGenerator() {
                  @Override
                  protected Multiset<String> create(String[] elements) {
                    return TreeMultiset.create(Arrays.asList(elements));
                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {

  }

  public Test testsForCheckedNavigableSet() {
    return SortedSetTestSuiteBuilder.using(
            new TestStringSortedSetGenerator() {
              @Override
              public NavigableSet<String> create(String[] elements) {
                NavigableSet<String> innerSet = new TreeSet<>();
                Collections.addAll(innerSet, elements);
                return Collections.checkedNavigableSet(innerSet, String.class);

  }

  public Test testsForEmptySet() {
    return SetTestSuiteBuilder.using(
            new TestStringSetGenerator() {
              @Override
              public Set<String> create(String[] elements) {
                return Collections.emptySet();
              }
            })
        .named("emptySet")
        .withFeatures(CollectionFeature.SERIALIZABLE, CollectionSize.ZERO)

    BiPredicate<Multimap<?, ?>, Multimap<?, ?>> equivalence =
        Equivalence.equals()
            .onResultOf((Multimap<?, ?> mm) -> ImmutableList.copyOf(mm.asMap().entrySet()))
            .and(Equivalence.equals());
    TreeMultimap<String, Integer> empty = TreeMultimap.create();
    TreeMultimap<String, Integer> filled = TreeMultimap.create();
    filled.put("a", 1);

  protected TreeBasedTable<String, Integer, Character> create(@Nullable Object... data) {
    TreeBasedTable<String, Integer, Character> table = TreeBasedTable.create();
    table.put("foo", 4, 'a');
    table.put("cat", 1, 'b');
    table.clear();
    populate(table, data);
    return table;
  }

  public void testCreateExplicitComparators() {
    table = TreeBasedTable.create(Collections.reverseOrder(), Ordering.usingToString());

                        mapEntry(Range.closed(20, 22), "umbrella"));
                  }

                  @Override
                  public Map<Range<Integer>, String> create(Object... elements) {
                    RangeMap<Integer, String> rangeMap = TreeRangeMap.create();
                    for (Object o : elements) {
                      @SuppressWarnings("unchecked")

    create().lastEntry();
  }

  public void testLastKey() {
    NavigableMap<String, Integer> map = create();
    map.put("a", 1);
    map.lastKey();
  }

  public void testLowerEntry() {
    create().lowerEntry("a");
  }

  public void testLowerKey() {
    create().lowerKey("a");
  }

  public void testNavigableKeySet() {
    NavigableMap<String, Integer> map = create();

	if err := DB.Omit("Languages.*").Create(&user).Error; err == nil {
		t.Fatalf("should raise error when create users without languages reference")
	}

	if err := DB.Create(&user.Languages).Error; err != nil {
		t.Fatalf("no error should happen when create languages, but got %v", err)
	}

	if err := DB.Omit("Languages.*").Create(&user).Error; err != nil {