assertThat(function.apply("Null")).isNull();

    new EqualsTester()
        .addEqualityGroup(function, Functions.forMap(map, 42))
        .addEqualityGroup(Functions.forMap(map))
        .addEqualityGroup(Functions.forMap(map, null))
        .addEqualityGroup(Functions.forMap(map, 43))
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester

    assertThat(function.apply("Null")).isNull();

    new EqualsTester()
        .addEqualityGroup(function, Functions.forMap(map, 42))
        .addEqualityGroup(Functions.forMap(map))
        .addEqualityGroup(Functions.forMap(map, null))
        .addEqualityGroup(Functions.forMap(map, 43))
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester

                    return multimap.build().keySet();
                  }
                })
            .named("Multimaps.forMap.keySet")
            .withFeatures(FOR_MAP_FEATURES_ANY)
            .createTestSuite());

    // TODO: use collection testers on Multimaps.forMap.values

    suite.addTest(
        MultisetTestSuiteBuilder.using(
                new TestStringMultisetGenerator() {

                    return multimap.build().keySet();
                  }
                })
            .named("Multimaps.forMap.keySet")
            .withFeatures(FOR_MAP_FEATURES_ANY)
            .createTestSuite());

    // TODO: use collection testers on Multimaps.forMap.values

    suite.addTest(
        MultisetTestSuiteBuilder.using(
                new TestStringMultisetGenerator() {

      Map<K, V> map) {
    return new FunctionForMapNoDefault<>(map);
  }

  /**
   * Returns a function which performs a map lookup with a default value. The function created by
   * this method returns {@code defaultValue} for all inputs that do not belong to the map's key
   * set. See also {@link #forMap(Map)}, which throws an exception in this case.
   *

    map.put("bar", 2);
    Multimap<String, Integer> multimapView = Multimaps.forMap(map);
    SerializableTester.reserializeAndAssert(multimapView);
  }

  public void testForMapRemoveAll() {
    Map<String, Integer> map = new HashMap<>();
    map.put("foo", 1);
    map.put("bar", 2);
    map.put("cow", 3);
    Multimap<String, Integer> multimap = Multimaps.forMap(map);
    assertEquals(3, multimap.size());