assertSame(INT_COMPARATOR, multimap.valueComparator());
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testSerializingUnmodifiableSynchronizedTreeMultimap() {
    TreeMultimap<String, Integer> delegate =
        TreeMultimap.create(Ordering.<String>natural(), INT_COMPARATOR);