* multiset1}, with repeated occurrences of the same element appearing consecutively.
   *
   * <p>Results are undefined if {@code multiset1} and {@code multiset2} are based on different
   * equivalence relations (as {@code HashMultiset} and {@code TreeMultiset} are).
   *
   * @since 14.0
   */
  public static <E extends @Nullable Object> Multiset<E> union(

   * multiset1}, with repeated occurrences of the same element appearing consecutively.
   *
   * <p>Results are undefined if {@code multiset1} and {@code multiset2} are based on different
   * equivalence relations (as {@code HashMultiset} and {@code TreeMultiset} are).
   *
   * @since 14.0
   */
  public static <E extends @Nullable Object> Multiset<E> union(

  enum Strength {
    STRONG {
      @Override
      Equivalence<Object> defaultEquivalence() {
        return Equivalence.equals();
      }
    },

    WEAK {
      @Override
      Equivalence<Object> defaultEquivalence() {
        return Equivalence.identity();
      }
    };

    /**
     * Returns the default equivalence strategy used to compare and hash keys or values referenced

     * elements.
     *
     * <p><b>Warning:</b> this may have unexpected results if a backing set of this view uses a
     * nonstandard notion of equivalence, for example if it is a {@link TreeSet} using a comparator
     * that is inconsistent with {@link Object#equals(Object)}.
     */
    public ImmutableSet<@NonNull E> immutableCopy() {

import static org.mockito.ArgumentMatchers.isA;
import static org.mockito.Mockito.eq;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import com.google.common.base.Equivalence;
import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import com.google.common.collect.testing.google.MultisetTestSuiteBuilder;

 * limitations under the License.
 */

package com.google.common.testing;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.base.CharMatcher;
import com.google.common.base.Equivalence;
import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.base.Splitter;
import com.google.common.base.Ticker;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Equivalence;
import com.google.common.base.Function;
import com.google.common.collect.MapMaker.Dummy;
import com.google.common.collect.MapMakerInternalMap.InternalEntry;
import com.google.errorprone.annotations.CanIgnoreReturnValue;

    assertThrows(IllegalArgumentException.class, () -> builder.setCount("a", -2));
  }

  public void testToImmutableSortedMultiset() {
    BiPredicate<ImmutableSortedMultiset<String>, ImmutableSortedMultiset<String>> equivalence =
        (ms1, ms2) ->
            ms1.equals(ms2)
                && ms1.entrySet().asList().equals(ms2.entrySet().asList())
                && ms1.comparator().equals(ms2.comparator());
    CollectorTester.of(

  }

  @Generates
  <T> Equivalence<T> generateEquivalence() {
    return new Equivalence<T>() {
      @Override
      protected boolean doEquivalent(T a, T b) {
        return false;
      }

      @Override
      protected int doHash(T t) {
        return 0;
      }

      final String string = paramString(Equivalence.class, generateInt());

      @Override

  }

  @Generates
  <T> Equivalence<T> generateEquivalence() {
    return new Equivalence<T>() {
      @Override
      protected boolean doEquivalent(T a, T b) {
        return false;
      }

      @Override
      protected int doHash(T t) {
        return 0;
      }

      final String string = paramString(Equivalence.class, generateInt());

      @Override