*/
  public <K extends K0, V extends V0> Multimap<K, V> build(
      Multimap<? extends K, ? extends V> multimap) {
    Multimap<K, V> result = build();
    result.putAll(multimap);
    return result;
  }

  /**
   * A specialization of {@link MultimapBuilder} that generates {@link ListMultimap} instances.
   *
   * @since 16.0
   */
  public abstract static class ListMultimapBuilder<

   */
  public <K extends K0, V extends V0> Multimap<K, V> build(
      Multimap<? extends K, ? extends V> multimap) {
    Multimap<K, V> result = build();
    result.putAll(multimap);
    return result;
  }

  /**
   * A specialization of {@link MultimapBuilder} that generates {@link ListMultimap} instances.
   *
   * @since 16.0
   */
  public abstract static class ListMultimapBuilder<

  }

  public void testMultimapReads() {
    Multimap<String, Integer> multimap = createMultimap();
    assertTrue(multimap.containsKey("foo"));
    assertFalse(multimap.containsKey("cat"));
    assertTrue(multimap.containsValue(1));
    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));

    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());
    assertThat(multimap.toString()).isEqualTo("{foo=[1, 3], bar=[2]}");
  }

  public void testMultimapWrites() {

    Collection<V> result = multimap().get(k0());
    assertTrue(result.add(v3()));
    assertTrue(multimap().containsKey(k0()));
    assertEquals(getNumElements() + 1, multimap().size());
    assertTrue(multimap().containsEntry(k0(), v3()));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPropagatesAddAllToMultimap() {
    Collection<V> result = multimap().get(k0());

 * implementation.
 *
 * @author Louis Wasserman
 */
@GwtIncompatible
public class MultimapTestSuiteBuilder<K, V, M extends Multimap<K, V>>
    extends PerCollectionSizeTestSuiteBuilder<
        MultimapTestSuiteBuilder<K, V, M>, TestMultimapGenerator<K, V, M>, M, Entry<K, V>> {

  public static <K, V, M extends Multimap<K, V>> MultimapTestSuiteBuilder<K, V, M> using(

  }

  @MapFeature.Require({SUPPORTS_PUT, SUPPORTS_REMOVE})
  public void testReplaceValuesWithDuplicates() {
    int size = multimap().size();
    List<V> oldValues = new ArrayList<>(multimap().get(k0()));
    List<V> values = asList(v0(), v3(), v0());
    assertEquals(oldValues, new ArrayList<V>(multimap().replaceValues(k0(), values)));

    assertFalse(multimap.containsValue(5));
    assertTrue(multimap.containsEntry("foo", 1));
    assertFalse(multimap.containsEntry("cat", 1));
    assertFalse(multimap.containsEntry("foo", 5));
    assertFalse(multimap.entries().isEmpty());
    assertEquals(3, multimap.size());
    assertFalse(multimap.isEmpty());
    assertThat(multimap.toString()).isEqualTo("{foo=[1, 3], bar=[2]}");
  }

 * already in the multimap has no effect. This interface does not specify the ordering of the
 * multimap's keys. See the {@link Multimap} documentation for information common to all multimaps.
 *
 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods each return a {@link
 * SortedSet} of values, while {@link Multimap#entries()} returns a {@link Set} of map entries.

        NullPointerException.class, () -> multimap().putAll(k3(), newArrayList(v3(), null)));

    Collection<V> values = multimap().get(k3());
    if (values.size() == 0) {
      expectUnchanged();
      // Be extra thorough in case internal state was corrupted by the expected null.
      assertEquals(new ArrayList<>(), new ArrayList<>(values));
      assertEquals(size, multimap().size());
    } else {