* @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)) {

	sort.Strings(required)

	take := func(sl *[]string) string {
		s := (*sl)[0]
		*sl = (*sl)[1:]
		return s
	}

	for len(features) > 0 || len(required) > 0 {
		switch {
		case len(features) == 0 || (len(required) > 0 && required[0] < features[0]):
			feature := take(&required)
			if exceptionSet[feature] {
				// An "unfortunate" case: the feature was once
				// included in the API (e.g. go1.txt), but was

import static com.google.common.collect.testing.features.FeatureUtil.getTesterAnnotations;
import static com.google.common.collect.testing.features.FeatureUtil.impliedFeatures;
import static com.google.common.collect.testing.features.FeatureUtilTest.ExampleFeature.BAR;
import static com.google.common.collect.testing.features.FeatureUtilTest.ExampleFeature.FOO;

          parentBuilder) {
    TestSetGenerator<E> delegate =
        (TestSetGenerator<E>) parentBuilder.getSubjectGenerator().getInnerGenerator();

    List<Feature<?>> features = new ArrayList<>();
    features.add(DESCENDING_VIEW);
    features.addAll(parentBuilder.getFeatures());

    return NavigableSetTestSuiteBuilder.using(
            new TestSetGenerator<E>() {

              @Override

    @Override
    public Iterable<E> order(List<E> insertionOrder) {
      return gen.order(insertionOrder);
    }
  }

  private static Set<Feature<?>> computeReserializedCollectionFeatures(Set<Feature<?>> features) {
    Set<Feature<?>> derivedFeatures = new HashSet<>(features);
    derivedFeatures.remove(SERIALIZABLE);
    derivedFeatures.remove(SERIALIZABLE_INCLUDING_VIEWS);
    return derivedFeatures;
  }

import com.google.common.collect.Multiset;
import com.google.common.collect.testing.features.Feature;
import com.google.common.collect.testing.features.TesterAnnotation;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Set;

/**
 * Optional features of classes derived from {@link Multiset}.
 *
 * @author Louis Wasserman
 */

import static com.google.common.collect.testing.features.FeatureUtil.addImpliedFeatures;
import static java.util.Arrays.asList;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.features.Feature;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ITERATOR_REMOVE;
import static com.google.common.collect.testing.features.CollectionSize.ONE;
import static com.google.common.collect.testing.features.CollectionSize.SEVERAL;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEYS;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEY_QUERIES;

import static com.google.common.collect.testing.features.CollectionSize.ZERO;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEYS;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEY_QUERIES;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUE_QUERIES;

import static com.google.common.collect.testing.features.CollectionFeature.ALLOWS_NULL_VALUES;
import static com.google.common.collect.testing.features.CollectionFeature.KNOWN_ORDER;
import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_ADD;
import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_REMOVE;
import static com.google.common.collect.testing.features.CollectionSize.ZERO;