*     .testEquals(); // or testNulls(), testSerializable() etc.
 * </pre>
 *
 * @author Ben Yu
 * @since 14.0
 */
@GwtIncompatible
@J2ktIncompatible
@NullUnmarked
@SuppressWarnings("nullness")
public final class ClassSanityTester {

  private static final Ordering<Invokable<?, ?>> BY_METHOD_NAME =
      new Ordering<Invokable<?, ?>>() {
        @Override

        default:
          /*
           * The suppression is safe because we ensure that the first `distinct` elements have been
           * populated.
           */
          @SuppressWarnings("nullness")
          Object[] elements =
              (distinct == dedupedElements.length)
                  ? dedupedElements
                  : Arrays.copyOf(dedupedElements, distinct);

   *
   * @since 7.0
   */
  public static <T extends @Nullable Object> List<T> reverse(List<T> list) {
    if (list instanceof ImmutableList) {
      // Avoid nullness warnings.
      List<?> reversed = ((ImmutableList<?>) list).reverse();
      @SuppressWarnings("unchecked")
      List<T> result = (List<T>) reversed;
      return result;
    } else if (list instanceof ReverseList) {

  /*
   * The following methods are safe to call as long as the conditions in the *previous* comment are
   * met *and* the index is less than size().
   *
   * (The above explains when these methods are safe from a `nullness` perspective. From an
   * `unchecked` perspective, they're safe because we put only K/V elements into each array.)
   */

  @SuppressWarnings("unchecked")
  private K key(int i) {

@J2ktIncompatible
@GwtIncompatible
@SuppressWarnings({
  "GuardedBy", // TODO(b/35466881): Fix or suppress.
  "nullness", // too much trouble for the payoff
})
@NullUnmarked // TODO(cpovirk): Annotate for nullness.
final class MapMakerInternalMap<
        K,
        V,
        E extends MapMakerInternalMap.InternalEntry<K, V, E>,

      return forward.descendingIterator();
    }

    @Override
    public @Nullable Object[] toArray() {
      return standardToArray();
    }

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

    @Override