keyIterator.next();
    keyIterator.remove();
    assertFalse(underlying.containsKey("c"));

    Collection<String> values = map.values();
    values.remove("4");
    assertFalse(underlying.containsKey("d"));

    Iterator<String> valueIterator = values.iterator();
    valueIterator.next();
    valueIterator.remove();
    assertFalse(underlying.containsKey("e"));

  }

  private SampleElements<V> values() {
    return new SampleElements<>(v0(), v1(), v2(), v3(), v4());
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testReplaceAllRotate() {
    getMap()
        .replaceAll(
            (K k, V v) -> {
              int index = keys().asList().indexOf(k);
              return values().asList().get(index + 1);
            });

existingThing.convention("some-value")
```

It's not acceptable to treat an unset Provider as if the convention is requested when the convention could be set elsewhere:

```groovy
public interface NewThing {
    Property<String> getSomeProperty()
}

// Unacceptable
String value
if (!getSomeProperty().isPresent()) {
   value = "convention"
} else {
   value = getSomeProperty().get()
}

  /**
   * Sets two distinct values for {@code type}. These values can be used for both null pointer
   * testing and equals testing.
   *
   * @since 17.0
   */
  protected final <T> void setDistinctValues(Class<T> type, T value1, T value2) {
    tester.setDistinctValues(type, value1, value2);
  }

  /** Specifies that classes that satisfy the given predicate aren't tested for sanity. */

		reflectValue = reflect.ValueOf(&user)
	)

	// test valuer
	values := map[string]interface{}{
		"name":       user.Name,
		"id":         user.ID,
		"created_at": user.CreatedAt,
		"updated_at": user.UpdatedAt,
		"deleted_at": user.DeletedAt,
		"age":        user.Age,
		"birthday":   user.Birthday,
		"active":     true,
	}
	checkField(t, userSchema, reflectValue, values)

	var f *bool
	// test setter

 *       as that of its keys. This is sometimes called an "invertible map," since the restriction on
 *       values enables it to support an {@linkplain BiMap#inverse inverse view} -- which is another
 *       instance of {@code BiMap}.
 *   <dt>{@link Table}
 *   <dd>A new type, which is similar to {@link java.util.Map}, but which indexes its values by an

            }

            int indexOfEntryWithValue(V value) {
              for (int i = 0; i < orderedEntries.size(); i++) {
                if (equal(orderedEntries.get(i).getValue(), value)) {
                  return i;
                }
              }
              throw new IllegalArgumentException(
                  "Map.values generator can order only sample values");
            }
          });

  /**
   * Associates {@code value} with {@code key} in this cache. If the cache previously contained a
   * value associated with {@code key}, the old value is replaced by {@code value}.
   *
   * <p>Prefer {@link #get(Object, Callable)} when using the conventional "if cached, return;
   * otherwise create, cache and return" pattern.
   *
   * @since 11.0
   */
  void put(K key, V value);

  /**

    Collection<V> values = multimap().get(k3());
    if (values.size() == 0) {
      expectUnchanged();
      // Be extra thorough in case internal state was corrupted by the expected null.
      assertEquals(new ArrayList<>(), new ArrayList<>(values));
      assertEquals(size, multimap().size());
    } else {
      assertEquals(newArrayList(v3()), new ArrayList<>(values));

        for (PomArtifactTransformer transformer : transformers.values()) {
            request = transformer.remapInstallArtifacts(session, request);
        }
        return request;
    }

    @Override
    public DeployRequest remapDeployArtifacts(RepositorySystemSession session, DeployRequest request) {
        for (PomArtifactTransformer transformer : transformers.values()) {