assertFalse(multimap().containsKey(k0()));
    assertFalse(multimap().containsEntry(k0(), v0()));
    assertEmpty(result);

    assertTrue(result.add(v1()));
    assertTrue(result.add(v2()));

    assertContentsAnyOrder(result, v1(), v2());
    assertContentsAnyOrder(multimap().get(k0()), v1(), v2());
    assertTrue(multimap().containsKey(k0()));
    assertFalse(multimap().containsEntry(k0(), v0()));

        assertTrue(map.containsKey("maven-test:t09-a"), "maven-test:t09-a is not in the project");
        assertTrue(map.containsKey("maven-test:t09-b"), "maven-test:t09-b is not in the project");
        assertTrue(map.containsKey("maven-test:t09-c"), "maven-test:t09-c is not in the project");
        assertTrue(map.containsKey("maven-test:t09-d"), "maven-test:t09-d is not in the project");
    }

    return delegate().remove(key);
  }

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

  @Override
  public boolean containsKey(@Nullable Object key) {
    return delegate().containsKey(key);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return delegate().containsValue(value);
  }

  @Override

        Map<String, String> aliases = lifecycle.getDelegate().aliases().stream()
                .collect(Collectors.toMap(a -> a.v3Phase(), a -> a.v4Phase()));

        if (aliases.containsKey(lifecyclePhase)) {
            lifecyclePhase = PhaseId.of(aliases.get(lifecyclePhase)).phase();
        }

        boolean passed = false;
        for (String phase : lifecycle.getPhases()) {

      return;
    }
    assertFalse(map.containsKey(unmappedKey));
    try {
      assertFalse(map.containsKey(new IncompatibleKeyType()));
    } catch (ClassCastException tolerated) {
    }
    assertTrue(map.containsKey(map.keySet().iterator().next()));
    if (allowsNullKeys) {
      boolean unused = map.containsKey(null);
    } else {
      try {

        map = null;
    }

    /**
     * @throws Exception
     */
    @Test
    public void testContainsKey() throws Exception {
        assertThat(map.containsKey("ONE"), is(true));
        assertThat(map.containsKey("one"), is(true));
        assertThat(map.containsKey("onex"), is(not(true)));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testGet() throws Exception {

      return value;
    }
  }

  final @Nullable V getWithoutCaching(Object key) {
    checkNotNull(key);
    return backingMap.get(key);
  }

  final boolean containsKey(@Nullable Object key) {
    return getIfCached(key) != null || backingMap.containsKey(key);
  }

  final Set<K> unmodifiableKeySet() {
    return new AbstractSet<K>() {
      @Override
      public UnmodifiableIterator<K> iterator() {

    }

    @Override
    public void clear() {
      assertTrue(Thread.holdsLock(mutex));
      super.clear();
    }

    @Override
    public boolean containsKey(Object key) {
      assertTrue(Thread.holdsLock(mutex));
      return super.containsKey(key);
    }

    @Override
    public boolean containsValue(Object value) {
      assertTrue(Thread.holdsLock(mutex));
      return super.containsValue(value);
    }

        if (!jApiMethod.getName().startsWith("getIs")) {
            return false;
        }
        String methodName = "get" + jApiMethod.getName().substring(5);
        return currentMethods.containsKey(AccessorKey.ofMethodWithSameSignatureButNewName(methodName, jApiMethod));
    }

    private static boolean isCurrentGetterThatReplacesBooleanIsGetter(JApiMethod jApiMethod, Map<AccessorKey, UpgradedProperty> currentMethods) {

@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible
public enum MapFeature implements Feature<Map> {
  /**
   * The map does not throw {@code NullPointerException} on calls such as {@code containsKey(null)},
   * {@code get(null)}, {@code keySet().contains(null)} or {@code remove(null)}.
   */
  ALLOWS_NULL_KEY_QUERIES,
  ALLOWS_NULL_KEYS(ALLOWS_NULL_KEY_QUERIES),
  /**