assertNotSame(features, FeatureUtil.impliedFeatures(features));
  }

  public void testImpliedFeatures_returnsImpliedFeatures() throws Exception {
    Set<Feature<?>> features;

    features = Sets.<Feature<?>>newHashSet(ExampleDerivedFeature.DERIVED_FEATURE_1);
    assertTrue(FeatureUtil.impliedFeatures(features).isEmpty());

    features = Sets.<Feature<?>>newHashSet(ExampleDerivedFeature.DERIVED_FEATURE_2);

    abstract Map<String, String> wrap(HashMap<String, String> map);
  }

  private static TestSuite wrappedHashMapTests(
      WrappedHashMapGenerator generator, String name, Feature<?>... features) {
    List<Feature<?>> featuresList = Lists.newArrayList(features);
    Collections.addAll(
        featuresList,
        MapFeature.GENERAL_PURPOSE,
        CollectionFeature.SUPPORTS_ITERATOR_REMOVE,
        CollectionSize.ANY);

   * @return the implied set of features
   */
  public static Set<Feature<?>> impliedFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> impliedSet = new LinkedHashSet<>();
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (!features.contains(implied) && impliedSet.add(implied)) {

    abstract Map<String, String> wrap(HashMap<String, String> map);
  }

  private static TestSuite wrappedHashMapTests(
      WrappedHashMapGenerator generator, String name, Feature<?>... features) {
    List<Feature<?>> featuresList = Lists.newArrayList(features);
    Collections.addAll(
        featuresList,
        MapFeature.GENERAL_PURPOSE,
        CollectionFeature.SUPPORTS_ITERATOR_REMOVE,
        CollectionSize.ANY);

   * @return the implied set of features
   */
  public static Set<Feature<?>> impliedFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> impliedSet = new LinkedHashSet<>();
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (!features.contains(implied) && impliedSet.add(implied)) {

  @CanIgnoreReturnValue
  public B withFeatures(Iterable<? extends Feature<?>> features) {
    for (Feature<?> feature : features) {
      this.features.add(feature);
    }
    return self();
  }

  public Set<Feature<?>> getFeatures() {
    return Collections.unmodifiableSet(features);
  }

  // Name

  private @Nullable String name;

  private static final Feature<?>[] COLLECTION_FEATURES = {
    CollectionSize.ANY, CollectionFeature.ALLOWS_NULL_QUERIES
  };

  private static final Feature<?>[] COLLECTION_FEATURES_ORDER = {
    CollectionSize.ANY, CollectionFeature.KNOWN_ORDER, CollectionFeature.ALLOWS_NULL_QUERIES
  };

  private static final Feature<?>[] COLLECTION_FEATURES_REMOVE = {

  @CanIgnoreReturnValue
  public B withFeatures(Iterable<? extends Feature<?>> features) {
    for (Feature<?> feature : features) {
      this.features.add(feature);
    }
    return self();
  }

  public Set<Feature<?>> getFeatures() {
    return Collections.unmodifiableSet(features);
  }

  // Name

  private @Nullable String name;

import com.google.common.collect.testing.DerivedCollectionGenerators.MapValueCollectionGenerator;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.MapFeature;
import com.google.common.collect.testing.testers.MapClearTester;

          .put(MapFeature.SUPPORTS_PUT, CollectionFeature.SUPPORTS_ADD)
          .build();

  Set<Feature<?>> computeMultimapGetFeatures(Set<Feature<?>> multimapFeatures) {
    Set<Feature<?>> derivedFeatures = Helpers.copyToSet(multimapFeatures);
    for (Entry<Feature<?>, Feature<?>> entry : GET_FEATURE_MAP.entries()) {
      if (derivedFeatures.contains(entry.getKey())) {
        derivedFeatures.add(entry.getValue());