My reading of their moving assignment operator is that it is wrong, or at the very least unclear.
Basically they do std::swap on query field. In that case you are relying on the destructor of the moved object performing the delete (if necessary). I would argue that that falls into the “too clever” spectrum, and also kind of assumes that no one is going to refactor the destructor at some point in such a way that some other property will result in them incorrectly thing that the query is null, and so leaking it.
Having now read through this, I agree with others assessment - these questions are questionable at best. What is it they’re proven to do?
Basically they do std::swap on query field. In that case you are relying on the destructor of the moved object performing the delete (if necessary). I would argue that that falls into the “too clever” spectrum, and also kind of assumes that no one is going to refactor the destructor at some point in such a way that some other property will result in them incorrectly thing that the query is null, and so leaking it.
Having now read through this, I agree with others assessment - these questions are questionable at best. What is it they’re proven to do?