@Test
public void test_singleton_file_fallback() throws Exception {

    SingletonParent singletonParent = config.get(SingletonParent.class);
    assertNotNull(singletonParent);
    // test that reference to other lookup exist
    assertThat(singletonParent.getProperty(), is(SINGLETON_PARENT_SCHEMA_NAME));
    Singleton singleton = singletonParent.getSingleton();
    assertNotNull(singleton);
    assertThat(singleton.getProperty(), is(SINGLETON_SCHEMA_NAME));
    // also check that references to other non-lookup instances exist
    Parent p10 = singleton.getParent();
    assertThat(p10.getProp1(), is("p10"));
    // ... and its references
    List<Child> children = p10.getProp7();
    assertNotNull(children);
    assertThat(children.size(), is(1));
    Child child = children.get(0);
    assertThat(child.getBeanId().getInstanceId(), is("c10"));
    assertThat(child.getProp11(), is(1.1f));
}