.testForwarding(
            SortedSet.class,
            new Function<SortedSet, SortedSet>() {
              @Override
              public SortedSet apply(SortedSet delegate) {
                return wrap(delegate);
              }
            });
  }

  public void testEquals() {
    SortedSet<String> set1 = ImmutableSortedSet.of("one");
    SortedSet<String> set2 = ImmutableSortedSet.of("two");

  }

  private static boolean hasSameComparator(Iterable<?> elements, Comparator<?> comparator) {
    if (elements instanceof SortedSet) {
      SortedSet<?> sortedSet = (SortedSet<?>) elements;
      Comparator<?> comparator2 = sortedSet.comparator();
      return (comparator2 == null)
          ? comparator == Ordering.natural()
          : comparator.equals(comparator2);
    }
    return false;
  }

public class SortedSetNavigationTester<E extends @Nullable Object> extends AbstractSetTester<E> {

  private SortedSet<E> sortedSet;
  private List<E> values;
  private @Nullable E a;
  private @Nullable E b;
  private @Nullable E c;

  @Override
  public void setUp() throws Exception {
    super.setUp();
    sortedSet = (SortedSet<E>) getSet();
    values =
        copyToList(
            getSubjectGenerator()

import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import org.jspecify.annotations.Nullable;

/**
 * Basic implementation of a {@link SortedSetMultimap} with a sorted key set.
 *
 * <p>This superclass allows {@code TreeMultimap} to override methods to return navigable set and
 * map types in non-GWT only, while GWT code will inherit the SortedMap/SortedSet overrides.
 *
 * @author Louis Wasserman
 */
@GwtCompatible

    for (Collection<V> valueCollection : multimap().asMap().values()) {
      SortedSet<V> valueSet = (SortedSet<V>) valueCollection;
      assertEquals(multimap().valueComparator(), valueSet.comparator());
    }
  }

  public void testAsMapGetImplementsSortedSet() {
    for (K key : multimap().keySet()) {
      SortedSet<V> valueSet = (SortedSet<V>) multimap().asMap().get(key);

 */
@SuppressWarnings("JdkObsolete")
public abstract class ForwardingSortedSet<E extends @Nullable Object> extends ForwardingSet<E>
    implements SortedSet<E> {

  /** Constructor for use by subclasses. */
  protected ForwardingSortedSet() {}

  @Override
  protected abstract SortedSet<E> delegate();

  @Override
  public @Nullable Comparator<? super E> comparator() {
    return delegate().comparator();
  }

  @Override

    ms.add("a", 1);
    ms.add("b", 3);
    ms.add("c", 2);
    ms.add("d", 1);
    ms.add("e", 3);
    ms.add("f", 2);

    SortedSet<String> elementSet = ms.elementSet();
    assertThat(elementSet).containsExactly("a", "b", "c", "d", "e", "f").inOrder();
    SortedSet<String> subset = elementSet.subSet("b", "f");
    assertThat(subset).containsExactly("b", "c", "d", "e").inOrder();

    assertTrue(subset.remove("c"));

  @Override
  public Comparator<? super E> comparator() {
    return delegate().comparator();
  }

  @Override
  SortedSet<E> createElementSet() {
    return Collections.unmodifiableSortedSet(delegate().elementSet());
  }

  @Override
  public SortedSet<E> elementSet() {
    return (SortedSet<E>) super.elementSet();
  }

  private transient @Nullable UnmodifiableSortedMultiset<E> descendingMultiset;

  @Override

    implements TestSortedSetGenerator<String> {

  @Override
  public SortedSet<String> create(Object... elements) {
    return (SortedSet<String>) super.create(elements);
  }

  @Override
  protected abstract SortedSet<String> create(String[] elements);

  /** Sorts the elements by their natural ordering. */
  /*

  public void testEmpty_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    SortedSet<String> copy = SerializableTester.reserializeAndAssert(set);
    assertEquals(set.comparator(), copy.comparator());
  }

  @GwtIncompatible // SerializableTester
  public void testSingle_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    set.add("e");