}

  static <K extends @Nullable Object, V extends @Nullable Object> BiMap<K, V> biMap(
      BiMap<K, V> bimap, @Nullable Object mutex) {
    if (bimap instanceof SynchronizedBiMap || bimap instanceof ImmutableBiMap) {
      return bimap;
    }
    return new SynchronizedBiMap<>(bimap, mutex, null);
  }

  }

  static <K extends @Nullable Object, V extends @Nullable Object> BiMap<K, V> biMap(
      BiMap<K, V> bimap, @Nullable Object mutex) {
    if (bimap instanceof SynchronizedBiMap || bimap instanceof ImmutableBiMap) {
      return bimap;
    }
    return new SynchronizedBiMap<>(bimap, mutex, null);
  }

      public <K extends Comparable<K>, V> BiMap<K, V> create(Map<K, V> map) {
        return HashBiMap.create(map);
      }
    },
    ImmutableBiMapImpl {
      @Override
      public <K extends Comparable<K>, V> BiMap<K, V> create(Map<K, V> map) {
        return ImmutableBiMap.copyOf(map);
      }
    };

    @Override
    public abstract <K extends Comparable<K>, V> BiMap<K, V> create(Map<K, V> map);
  }

  public void testIdentityKeySetIteratorRemove() {
    BiMap<Integer, String> bimap =
        new AbstractBiMap<Integer, String>(
            new IdentityHashMap<Integer, String>(), new IdentityHashMap<String, Integer>()) {};
    bimap.put(1, "one");
    bimap.put(2, "two");
    bimap.put(3, "three");
    Iterator<Integer> iterator = bimap.keySet().iterator();
    iterator.next();
    iterator.next();

  public void testIdentityKeySetIteratorRemove() {
    BiMap<Integer, String> bimap =
        new AbstractBiMap<Integer, String>(
            new IdentityHashMap<Integer, String>(), new IdentityHashMap<String, Integer>()) {};
    bimap.put(1, "one");
    bimap.put(2, "two");
    bimap.put(3, "three");
    Iterator<Integer> iterator = bimap.keySet().iterator();
    iterator.next();
    iterator.next();

import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_REMOVE;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.BiMap;
import com.google.common.collect.testing.features.MapFeature;
import org.junit.Ignore;

/**
 * Tester for {@code BiMap.clear}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import java.util.Collections;
import java.util.List;
import org.junit.Ignore;

/**
 * Tests for the {@code inverse} view of a BiMap.
 *
 * <p>This assumes that {@code bimap.inverse().inverse() == bimap}, which is not technically
 * required but is fulfilled by all current implementations.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

/**
 * A {@code BiMap} backed by an {@code EnumMap} instance for keys-to-values, and a {@code HashMap}
 * instance for values-to-keys. Null keys are not permitted, but null values are. An {@code
 * EnumHashBiMap} and its inverse are both serializable.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#bimap">{@code BiMap}</a>.
 *
 * @author Mike Bostock

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.BiMap;
import com.google.common.collect.ImmutableBiMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;

/**
 * Generators of various {@link com.google.common.collect.BiMap}s and derived collections.
 *
 * @author Jared Levy
 * @author Hayward Chan
 */

import com.google.common.collect.BiMap;
import com.google.common.collect.testing.AbstractMapTester;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;
import org.junit.Ignore;

/** Skeleton for a tester of a {@code BiMap}. */
@GwtCompatible