"putIfAbsent(notPresent, value) should return null", getMap().putIfAbsent(k3(), v3()));
    expectAdded(e3());
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testPutIfAbsent_supportedPresent() {
    assertEquals(
        "putIfAbsent(present, value) should return existing value",
        v0(),
        getMap().putIfAbsent(k0(), v3()));
    expectUnchanged();
  }

    for (Entry<K, V> entry : getMap().entrySet()) {
      assertThrows(NullPointerException.class, () -> entry.setValue(null));
      expectUnchanged();
    }
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullSupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      if (entry.getKey().equals(k0())) {

  @MapFeature.Require(SUPPORTS_PUT)
  public void testAbsent() {
    assertEquals(
        "Map.merge(absent, value, function) should return value",
        v3(),
        getMap()
            .merge(
                k3(),
                v3(),
                (oldV, newV) -> {
                  throw new AssertionFailedError(

  public void testReplaceAllPreservesOrder() {
    getMap()
        .replaceAll(
            (K k, V v) -> {
              int index = keys().asList().indexOf(k);
              return values().asList().get(index + 1);
            });
    List<Entry<K, V>> orderedEntries = getOrderedElements();
    int index = 0;
    for (K key : getMap().keySet()) {
      assertEquals(orderedEntries.get(index).getKey(), key);

  public void testToString_minimal() {
    assertNotNull("toString() should not return null", getMap().toString());
  }

  @CollectionSize.Require(ZERO)
  @CollectionFeature.Require(absent = NON_STANDARD_TOSTRING)
  public void testToString_size0() {
    assertEquals("emptyMap.toString should return {}", "{}", getMap().toString());
  }

  @CollectionSize.Require(ONE)

  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAll_supportedNothing() {
    getMap().putAll(emptyMap());
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testPutAll_unsupportedNothing() {
    try {
      getMap().putAll(emptyMap());
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }

  public void testForEachKnownOrder() {
    List<Entry<K, V>> entries = new ArrayList<>();
    getMap().forEach((k, v) -> entries.add(entry(k, v)));
    assertEquals(getOrderedElements(), entries);
  }

  @CollectionFeature.Require(absent = KNOWN_ORDER)
  public void testForEachUnknownOrder() {
    List<Entry<K, V>> entries = new ArrayList<>();
    getMap().forEach((k, v) -> entries.add(entry(k, v)));

  public void testForEachKnownOrder() {
    List<Entry<K, V>> entries = new ArrayList<>();
    getMap().forEach((k, v) -> entries.add(entry(k, v)));
    assertEquals(getOrderedElements(), entries);
  }

  @CollectionFeature.Require(absent = KNOWN_ORDER)
  public void testForEachUnknownOrder() {
    List<Entry<K, V>> entries = new ArrayList<>();
    getMap().forEach((k, v) -> entries.add(entry(k, v)));

  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testPut_supportedPresent() {
    assertEquals("put(present, value) should return the old value", v0(), getMap().put(k0(), v3()));
    expectReplacement(entry(k0(), v3()));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPut_supportedNotPresent() {
    assertNull("put(notPresent, value) should return null", put(e3()));

  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAll_supportedNothing() {
    getMap().putAll(emptyMap());
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testPutAll_unsupportedNothing() {
    try {
      getMap().putAll(emptyMap());
    } catch (UnsupportedOperationException tolerated) {
    }
    expectUnchanged();
  }