import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multimaps;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.Immutable;
import com.google.errorprone.annotations.concurrent.LazyInit;

   * assertThat(colorForName).containsEntry("red", red);
   * }
   *
   * <p>If your index may associate multiple values with each key, use {@link
   * Multimaps#index(Iterable, Function) Multimaps.index}.
   *
   * <p><b>Note:</b> on Java 8+, it is usually better to use streams. For example:
   *
   * {@snippet :
   * import static com.google.common.collect.ImmutableMap.toImmutableMap;

   * assertThat(colorForName).containsEntry("red", red);
   * }
   *
   * <p>If your index may associate multiple values with each key, use {@link
   * Multimaps#index(Iterable, Function) Multimaps.index}.
   *
   * <p><b>Note:</b> on Java 8+, it is usually better to use streams. For example:
   *
   * {@snippet :
   * import static com.google.common.collect.ImmutableMap.toImmutableMap;

   * iterable will be stored as a value in the resulting multimap, yielding a multimap with the same
   * size as this iterable. The key used to store that value in the multimap will be the result of
   * calling the function on that value. The resulting multimap is created as an immutable snapshot.
   * In the returned multimap, keys appear in the order they are first encountered, and the values

        assertThrows(
            IllegalArgumentException.class,
            () -> Maps.uniqueIndex(ImmutableSet.of("one", "uno"), Functions.constant(1)));
    assertThat(expected).hasMessageThat().contains("Multimaps.index");
  }

  /** Null values are not allowed. */
  public void testUniqueIndexNullValue() {
    List<@Nullable String> listWithNull = Lists.newArrayList((String) null);
    assertThrows(

        assertThrows(
            IllegalArgumentException.class,
            () -> Maps.uniqueIndex(ImmutableSet.of("one", "uno"), Functions.constant(1)));
    assertThat(expected).hasMessageThat().contains("Multimaps.index");
  }

  /** Null values are not allowed. */
  public void testUniqueIndexNullValue() {
    List<@Nullable String> listWithNull = Lists.newArrayList((String) null);
    assertThrows(

    SetMultimap<K, V> multimap1 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k0(), v4()));
    SetMultimap<K, V> multimap2 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v1()), mapEntry(k0(), v0()), mapEntry(k0(), v4()));
    new EqualsTester().addEqualityGroup(multimap1, multimap2).testEquals();
  }

    ListMultimap<K, V> multimap1 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k0(), v0()));
    ListMultimap<K, V> multimap2 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v1()), mapEntry(k0(), v0()), mapEntry(k0(), v0()));
    new EqualsTester().addEqualityGroup(multimap1).addEqualityGroup(multimap2).testEquals();
  }

    } catch (UnsupportedOperationException expected) {
    }
    assertMultimapRemainsUnmodified(multimap, originalEntries);

    // Test #putAll(Multimap<K, V>)
    Multimap<K, V> multimap2 = ArrayListMultimap.create();
    multimap2.put(sampleKey, sampleValue);
    try {
      multimap.putAll(multimap2);
      fail("putAll(Multimap<K, V>) succeeded on unmodifiable multimap");

    ListMultimap<K, V> multimap1 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v0()), mapEntry(k0(), v1()), mapEntry(k0(), v0()));
    ListMultimap<K, V> multimap2 =
        getSubjectGenerator()
            .create(mapEntry(k0(), v1()), mapEntry(k0(), v0()), mapEntry(k0(), v0()));
    new EqualsTester().addEqualityGroup(multimap1).addEqualityGroup(multimap2).testEquals();
  }