@Test(expected = AssertionError.class)
 public void
     testAssertThat_child_at_property_path_builder_does_exist_fails_when_child_doesnt_exist() {
   assertThat(null)
       .child(PropertyPath.createBuilder().withRoot().withPropertyName("value"))
       .doesExist();
 }
 @Test
 public void testAssertThat_child_at_property_path_builder_does_exist_succeeds_when_child_exist() {
   final ObjectWithString working = new ObjectWithString("foo");
   final ObjectWithString base = new ObjectWithString("bar");
   final Node node = ObjectDifferFactory.getInstance().compare(working, base);
   assertThat(node)
       .child(PropertyPath.createBuilder().withRoot().withPropertyName("value"))
       .doesExist();
 }