/** Tests for {@link AbstractSequentialIterator}. */
@GwtCompatible
@NullMarked
public class AbstractSequentialIteratorTest extends TestCase {
  @GwtIncompatible // Too slow
  public void testDoublerExhaustive() {
    new IteratorTester<Integer>(
        3, UNMODIFIABLE, ImmutableList.of(1, 2), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<Integer> newTargetIterator() {