@Override
    protected Map<AnEnum, String> create(Entry<AnEnum, String>[] entries) {
      EnumMap<AnEnum, String> map = new EnumMap<>(AnEnum.class);
      for (Entry<AnEnum, String> entry : entries) {
        map.put(entry.getKey(), entry.getValue());
      }
      return ImmutableMap.copyOf(map);
    }

    @Override
    public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {

    ImmutableMap<AnEnum, String> map =
        Maps.immutableEnumMap(ImmutableMap.of(AnEnum.C, "c", AnEnum.A, "a", AnEnum.E, "e"));

    assertThat(map.entrySet())
        .containsExactly(mapEntry(AnEnum.A, "a"), mapEntry(AnEnum.C, "c"), mapEntry(AnEnum.E, "e"))
        .inOrder();
  }

  public void testToImmutableEnumMap() {
    Collector<Entry<AnEnum, Integer>, ?, ImmutableMap<AnEnum, Integer>> collector =

    @Override
    protected Map<AnEnum, String> create(Entry<AnEnum, String>[] entries) {
      EnumMap<AnEnum, String> map = new EnumMap<>(AnEnum.class);
      for (Entry<AnEnum, String> entry : entries) {
        map.put(entry.getKey(), entry.getValue());
      }
      return ImmutableMap.copyOf(map);
    }

    @Override
    public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {

    return suite;
  }

  public void testIteratesOnce() {
    Map<AnEnum, AnEnum> map =
        Maps.asMap(
            ImmutableSet.of(AnEnum.A),
            new Function<AnEnum, AnEnum>() {
              boolean used = false;

              @Override
              public AnEnum apply(AnEnum ae) {
                checkState(!used, "should not be applied more than once");
                used = true;

  private static TestEnumMultisetGenerator enumMultisetGenerator() {
    return new TestEnumMultisetGenerator() {
      @Override
      protected Multiset<AnEnum> create(AnEnum[] elements) {
        return (elements.length == 0)
            ? EnumMultiset.create(AnEnum.class)
            : EnumMultiset.create(asList(elements));
      }
    };
  }

  private enum Color {
    BLUE,
    RED,
    YELLOW,
    GREEN,

  private static TestEnumMultisetGenerator enumMultisetGenerator() {
    return new TestEnumMultisetGenerator() {
      @Override
      protected Multiset<AnEnum> create(AnEnum[] elements) {
        return (elements.length == 0)
            ? EnumMultiset.create(AnEnum.class)
            : EnumMultiset.create(asList(elements));
      }
    };
  }

  private enum Color {
    BLUE,
    RED,
    YELLOW,
    GREEN,

    suite.addTest(
        SetTestSuiteBuilder.using(
                new TestEnumSetGenerator() {
                  @Override
                  protected Set<AnEnum> create(AnEnum[] elements) {
                    AnEnum[] otherElements = new AnEnum[elements.length - 1];
                    arraycopy(elements, 1, otherElements, 0, otherElements.length);
                    return Sets.immutableEnumSet(elements[0], otherElements);