Make QueryByExampleExecutor ignore Null values with MongoDb

Question

I am trying to use findAll(Example<S> example) of MongoRepository in order to filter for specific documents.

I have following nested data structure:

@Data
@Document
@Builder
@Jacksonized
public class House {

    private  List<Room> rooms;
    private String name;

}

@Data
@Builder
@Jacksonized
public class Room {
    private List<Chair> chairs;
}

@Data
@Builder
@Jacksonized
public class Chair {
    private String color;
    private Long countOfLegs;
}

Now I create two houses with corresponding rooms and chairs. Only house1 has an chair with 3 legs and only house2 has chairs with 5 legs.

I am trying to use findAll with Examples for this case:

    @Test
    @SneakyThrows
    void contextLoads() {

        final House house1hasChairWith3Legs = getHouse1();
        final House house2hasChairWith5Legs = getHouse2();
        final List<House> testData = List.of(house1hasChairWith3Legs, house2hasChairWith5Legs);
        repository.insert(testData);

        final ExampleMatcher matcher = ExampleMatcher.matchingAll().withIgnoreNullValues();

        final House probe = House.builder()
                .rooms(List.of(Room.builder().chairs(List.of(Chair.builder().countOfLegs(3L).build())).build()))
                .build();
        final Example<House> example = Example.of(probe, matcher);

        final List<House> result = repository.findAll(example); // empty result
        assertEquals(1, result.size());
    }

result is empty. Logging the query shows me that following query is used:

{ "rooms" : [{ "chairs" : [{ "countOfLegs" : 3}]}] ... }

Regarding the warning in https://www.mongodb.com/docs/manual/tutorial/query-embedded-documents/#match-an-embedded-nested-document I would expect a query with dot notation, like: {"rooms.chairs.countOfLegs": 3}. This query leads to the expected result.

Is there some configuration to use queries with dot notation? Is this expected behavior?

See https://github.com/the-bug/QueryByExampleExecutor---MongoDB/tree/master for playing around.

I was reading the specs of nested queries and tried option of the ExampleMatcher.