@J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testStringConverterSerialization() {
    SerializableTester.reserializeAndAssert(Doubles.stringConverter());
  }

  public void testToArray() {
    // need explicit type parameter to avoid javac warning!?
    List<Double> none = Arrays.<Double>asList();
    assertThat(Doubles.toArray(none)).isEqualTo(EMPTY);

    List<Double> one = Arrays.asList(1.0);

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testStringConverterSerialization() {
    SerializableTester.reserializeAndAssert(Floats.stringConverter());
  }

  public void testToArray() {
    // need explicit type parameter to avoid javac warning!?
    List<Float> none = Arrays.<Float>asList();
    assertThat(Floats.toArray(none)).isEqualTo(EMPTY);

    List<Float> one = Arrays.asList(1.0f);

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testStringConverterSerialization() {
    SerializableTester.reserializeAndAssert(Ints.stringConverter());
  }

  public void testToArray() {
    // need explicit type parameter to avoid javac warning!?
    List<Integer> none = Arrays.<Integer>asList();
    assertThat(Ints.toArray(none)).isEqualTo(EMPTY);

    List<Integer> one = Arrays.asList((int) 1);

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testStringConverterSerialization() {
    SerializableTester.reserializeAndAssert(Floats.stringConverter());
  }

  public void testToArray() {
    // need explicit type parameter to avoid javac warning!?
    List<Float> none = Arrays.<Float>asList();
    assertThat(Floats.toArray(none)).isEqualTo(EMPTY);

    List<Float> one = Arrays.asList(1.0f);

    String[] array = Iterators.toArray(iterator, String.class);
    assertThat(array).isEqualTo(new String[] {"a"});
  }

  @GwtIncompatible // Iterators.toArray(Iterator, Class)
  public void testToArray() {
    String[] sourceArray = new String[] {"a", "b", "c"};
    Iterator<String> iterator = asList(sourceArray).iterator();
    String[] newArray = Iterators.toArray(iterator, String.class);