RegularImmutableSet<String> set = (RegularImmutableSet<String>) builder.build();
    assertTrue(set.elements.length <= 2 * set.size());
  }

  @GwtIncompatible // internals
  public void testReusedBuilder() {
    ImmutableSet.Builder<String> builder = new ImmutableSet.Builder<String>();
    for (int i = 0; i < 10; i++) {
      builder.add("foo");
    }
    builder.add("bar");

  public void testAsList() {
    ImmutableList<String> list = ImmutableList.of("a", "b");
    assertThat(list.asList()).isSameInstanceAs(list);
  }

  @GwtIncompatible // builder internals
  public void testReusedBuilder() {
    ImmutableList.Builder<String> builder = new ImmutableList.Builder<String>();
    for (int i = 0; i < 10; i++) {
      builder.add("foo");
    }
    builder.add("bar");

    RegularImmutableList<String> list = (RegularImmutableList<String>) set.elements;
    assertTrue(list.array.length <= 2 * set.size());
  }

  @GwtIncompatible // internals
  public void testReusedBuilder() {
    ImmutableSortedSet.Builder<String> builder = ImmutableSortedSet.naturalOrder();
    for (int i = 0; i < 10; i++) {
      builder.add("foo");
    }
    builder.add("bar");