Ordering<@Nullable Integer> ordering = Ordering.<Integer>natural().<Integer>nullsFirst();
    Helpers.<@Nullable Integer>testComparator(ordering, null, Integer.MIN_VALUE, 0, 1);

    new EqualsTester()
        .addEqualityGroup(ordering, Ordering.natural().nullsFirst())
        .addEqualityGroup(numberOrdering.nullsFirst())
        .addEqualityGroup(Ordering.natural())
        .testEquals();
  }

    Ordering<@Nullable Integer> ordering = Ordering.<Integer>natural().<Integer>nullsFirst();
    Helpers.<@Nullable Integer>testComparator(ordering, null, Integer.MIN_VALUE, 0, 1);

    new EqualsTester()
        .addEqualityGroup(ordering, Ordering.natural().nullsFirst())
        .addEqualityGroup(numberOrdering.nullsFirst())
        .addEqualityGroup(Ordering.natural())
        .testEquals();
  }

    return insertionOrder;
  }

  /**
   * Compares strings in natural order except that null comes immediately before a given value. This
   * works better than Ordering.natural().nullsFirst() because, if null comes before all other
   * values, it lies outside the submap/submultiset ranges we test, and the variety of tests that
   * exercise null handling fail on those subcollections.
   */

    return insertionOrder;
  }

  /**
   * Compares strings in natural order except that null comes immediately before a given value. This
   * works better than Ordering.natural().nullsFirst() because, if null comes before all other
   * values, it lies outside the submap/submultiset ranges we test, and the variety of tests that
   * exercise null handling fail on those subcollections.
   */

 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public class MultimapsTest extends TestCase {

  private static final Comparator<Integer> INT_COMPARATOR =
      Ordering.<Integer>natural().reverse().nullsFirst();

  @SuppressWarnings({"deprecation", "InlineMeInliner"}) // test of a deprecated method
  public void testUnmodifiableListMultimapShortCircuit() {
    ListMultimap<String, Integer> mod = ArrayListMultimap.create();