}

    @Override
    @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
    public <T extends @Nullable Object> T[] toArray(T[] array) {
      return Lists.newArrayList(iterator()).toArray(array);
    }
  }

  /**
   * Returns a collection that applies {@code function} to each element of {@code fromCollection}.

  public void testRetainAll_duplicatesKept() {
    E[] array = createSamplesArray();
    array[1] = e0();
    collection = getSubjectGenerator().create(array);
    assertFalse(
        "containsDuplicates.retainAll(superset) should return false",
        collection.retainAll(MinimalCollection.of(createSamplesArray())));
    expectContents(array);
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)

    assertThat(Doubles.toArray(bytes)).isEqualTo(array);
    assertThat(Doubles.toArray(shorts)).isEqualTo(array);
    assertThat(Doubles.toArray(ints)).isEqualTo(array);
    assertThat(Doubles.toArray(floats)).isEqualTo(array);
    assertThat(Doubles.toArray(longs)).isEqualTo(array);
    assertThat(Doubles.toArray(doubles)).isEqualTo(array);
  }

    assertThat(Longs.toArray(bytes)).isEqualTo(array);
    assertThat(Longs.toArray(shorts)).isEqualTo(array);
    assertThat(Longs.toArray(ints)).isEqualTo(array);
    assertThat(Longs.toArray(floats)).isEqualTo(array);
    assertThat(Longs.toArray(longs)).isEqualTo(array);
    assertThat(Longs.toArray(doubles)).isEqualTo(array);
  }

    assertThat(Doubles.toArray(bytes)).isEqualTo(array);
    assertThat(Doubles.toArray(shorts)).isEqualTo(array);
    assertThat(Doubles.toArray(ints)).isEqualTo(array);
    assertThat(Doubles.toArray(floats)).isEqualTo(array);
    assertThat(Doubles.toArray(longs)).isEqualTo(array);
    assertThat(Doubles.toArray(doubles)).isEqualTo(array);
  }

    assertThat(Longs.toArray(bytes)).isEqualTo(array);
    assertThat(Longs.toArray(shorts)).isEqualTo(array);
    assertThat(Longs.toArray(ints)).isEqualTo(array);
    assertThat(Longs.toArray(floats)).isEqualTo(array);
    assertThat(Longs.toArray(longs)).isEqualTo(array);
    assertThat(Longs.toArray(doubles)).isEqualTo(array);
  }

  @SuppressWarnings("DoNotCall")
  public void testRemove() {
    final String[] array = {"a", "b", "c"};

    Iterator<String> iterator =
        new UnmodifiableIterator<String>() {
          int i;

          @Override
          public boolean hasNext() {
            return i < array.length;
          }

          @Override
          public String next() {
            if (!hasNext()) {

    return new Strings();
  }

  @Override
  public Queue<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Queue<String> create(String[] elements);

  @Override
  public String[] createArray(int length) {

    return new Strings();
  }

  @Override
  public Collection<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Collection<String> create(String[] elements);

  @Override
  public String[] createArray(int length) {

    return new Strings();
  }

  @Override
  public Set<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Set<String> create(String[] elements);

  @Override
  public String[] createArray(int length) {