@Override
              protected NavigableMap<String, String> create(Entry<String, String>[] entries) {
                return Collections.unmodifiableNavigableMap(populate(new TreeMap<>(), entries));
              }
            })
        .named("unmodifiableNavigableMap/TreeMap, natural")
        .withFeatures(
            MapFeature.ALLOWS_NULL_VALUES,
            CollectionFeature.KNOWN_ORDER,

                    SafeTreeMap<String, String> map = new SafeTreeMap<>();
                    putEntries(map, entries);
                    return Maps.unmodifiableNavigableMap(map);
                  }
                })
            .named("unmodifiableNavigableMap[SafeTreeMap]")
            .withFeatures(
                CollectionSize.ANY, MapFeature.ALLOWS_NULL_VALUES, CollectionFeature.SERIALIZABLE)
            .createTestSuite());

                    SafeTreeMap<String, String> map = new SafeTreeMap<>();
                    putEntries(map, entries);
                    return Maps.unmodifiableNavigableMap(map);
                  }
                })
            .named("unmodifiableNavigableMap[SafeTreeMap]")
            .withFeatures(
                CollectionSize.ANY, MapFeature.ALLOWS_NULL_VALUES, CollectionFeature.SERIALIZABLE)
            .createTestSuite());

          .put(ImmutableMap.class, ImmutableMap.of())
          .put(SortedMap.class, ImmutableSortedMap.of())
          .put(ImmutableSortedMap.class, ImmutableSortedMap.of())
          .put(NavigableMap.class, Maps.unmodifiableNavigableMap(Maps.newTreeMap()))
          .put(Multimap.class, ImmutableMultimap.of())
          .put(ImmutableMultimap.class, ImmutableMultimap.of())
          .put(ListMultimap.class, ImmutableListMultimap.of())

          .put(ImmutableMap.class, ImmutableMap.of())
          .put(SortedMap.class, ImmutableSortedMap.of())
          .put(ImmutableSortedMap.class, ImmutableSortedMap.of())
          .put(NavigableMap.class, Maps.unmodifiableNavigableMap(Maps.newTreeMap()))
          .put(Multimap.class, ImmutableMultimap.of())
          .put(ImmutableMultimap.class, ImmutableMultimap.of())
          .put(ListMultimap.class, ImmutableListMultimap.of())