@Test
void delegatesValues() {

    final String key = UUID.randomUUID()
        .toString();
    final String value = UUID.randomUUID()
        .toString();
    final InstanceState<String> parent = mock(InstanceState.class);
    when(parent.getValue(key)).thenReturn(Optional.of(value));
    final TransactionalInstanceState<String> s = new TransactionalInstanceState<>(Collections.emptyList(), parent);
    assertThat(s.getValue(key)).contains(value);
}