public static <K, V> ImmutableMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    if ((map instanceof ImmutableMap) && !(map instanceof ImmutableSortedMap)) {
      @SuppressWarnings("unchecked") // safe since map is not writable
      ImmutableMap<K, V> kvMap = (ImmutableMap<K, V>) map;
      return kvMap;
    } else if (map instanceof EnumMap) {
      EnumMap<?, ?> enumMap = (EnumMap<?, ?>) map;

   *
   * @see #assertMoreInvariants
   * @param map the map to check.
   */
  protected final void assertInvariants(Map<K, V> map) {
    Set<K> keySet = map.keySet();
    Collection<V> valueCollection = map.values();
    Set<Entry<K, V>> entrySet = map.entrySet();

    assertEquals(map.size() == 0, map.isEmpty());
    assertEquals(map.size(), keySet.size());
    assertEquals(keySet.size() == 0, keySet.isEmpty());

    MapMakerInternalMap<Object, Object, ?, ?> map = makeMap(createMapMaker());

    assertSame(Strength.STRONG, map.keyStrength());
    assertSame(Strength.STRONG, map.valueStrength());
    assertSame(map.keyStrength().defaultEquivalence(), map.keyEquivalence);
    assertSame(map.valueStrength().defaultEquivalence(), map.valueEquivalence());

    assertThat(map.entryHelper)

    MapMakerInternalMap<Object, Object, ?, ?> map = makeMap(createMapMaker());

    assertSame(Strength.STRONG, map.keyStrength());
    assertSame(Strength.STRONG, map.valueStrength());
    assertSame(map.keyStrength().defaultEquivalence(), map.keyEquivalence);
    assertSame(map.valueStrength().defaultEquivalence(), map.valueEquivalence());

    assertThat(map.entryHelper)

    @Override
    protected final Map<String, String> create(Entry<String, String>[] entries) {
      HashMap<String, String> map = Maps.newHashMap();
      for (Entry<String, String> entry : entries) {
        map.put(entry.getKey(), entry.getValue());
      }
      return wrap(map);
    }

    abstract Map<String, String> wrap(HashMap<String, String> map);
  }

  private static TestSuite wrappedHashMapTests(

    private final AtomicBoolean setUpRan;

    CheckSetUpInvocationHandler(Map<String, String> map, AtomicBoolean setUpRan) {
      this.map = map;
      this.setUpRan = setUpRan;
    }

    @Override
    public Object invoke(Object target, Method method, Object[] args) throws Throwable {
      assertTrue("setUp should have run", setUpRan.get());
      try {
        return method.invoke(map, args);

                  @Override
                  protected Map<String, String> create(Entry<String, String>[] entries) {
                    Map<String, String> map = Maps.newHashMap();
                    putEntries(map, entries);
                    map.putAll(ENTRIES_TO_FILTER);
                    map = Maps.filterEntries(map, FILTER_ENTRIES_1);
                    return Maps.filterEntries(map, FILTER_ENTRIES_2);
                  }

    IntHolder holderB = new IntHolder(2);
    Map<String, IntHolder> map = ImmutableSortedMap.of("a", holderA, "b", holderB);
    holderA.value = 3;
    assertTrue(map.entrySet().contains(Maps.immutableEntry("a", new IntHolder(3))));
    Map<String, Integer> intMap = ImmutableSortedMap.of("a", 3, "b", 2);
    assertEquals(intMap.hashCode(), map.entrySet().hashCode());
    assertEquals(intMap.hashCode(), map.hashCode());
  }

  @J2ktIncompatible

    final ConcurrentMap<?, ?> map;

    AbstractCacheSet(ConcurrentMap<?, ?> map) {
      this.map = map;
    }

    @Override
    public int size() {
      return map.size();
    }

    @Override
    public boolean isEmpty() {
      return map.isEmpty();
    }

    @Override
    public void clear() {
      map.clear();
    }
  }

     * map.remove(x)} returns the same value which {@code map.get(x)} did immediately beforehand.
     */
    @Override
    public void testRemove() {
      final Map<String, Map<Integer, Character>> map;
      final String keyToRemove;
      try {
        map = makePopulatedMap();
      } catch (UnsupportedOperationException e) {
        return;
      }
      keyToRemove = map.keySet().iterator().next();