MongoEngine/mongoengine — pull request #199 by wojcikstefan (2012-12-18 03:00:57+00:00)
Title: Only allow QNode instances to be passed as positional arguments

Assume `SomeDoc.objects.filter(obj1=obj1, obj2=obj2)` returns some objects. `SomeDoc.objects.filter(obj1, obj2)` should not return ALL of them. This is especially unsafe, if combined with `.delete()`. This fix makes sure the positional arguments passed to `filter` are in fact instances of QNode.