Commit 272de9eb authored by David Cramer's avatar David Cramer
Browse files

Send post_delete signals immediately 

In a normal relational construct, if you're listening for an event
that signals a child was deleted, you dont expect that the parent
was deleted already.

This change ensures that post_delete signals are fired immediately
after objects are deleted in the graph.
parent 4720117a

django/db/models/deletion.py

+12 −10
Original line number Diff line number Diff line
@@ -262,6 +262,14 @@ class Collector(object): 
        self.data = SortedDict([(model, self.data[model])

                                for model in sorted_models])



    def send_post_delete_signals(self, model, instances):

        if model._meta.auto_created:

            return

        for obj in instances:

            signals.post_delete.send(

                sender=model, instance=obj, using=self.using

            )



    @force_managed

    def delete(self):

        # sort instance collections
@@ -300,13 +308,7 @@ class Collector(object): 
            query = sql.DeleteQuery(model)

            pk_list = [obj.pk for obj in instances]

            query.delete_batch(pk_list, self.using)



        # send post_delete signals

        for model, obj in self.instances_with_model():

            if not model._meta.auto_created:

                signals.post_delete.send(

                    sender=model, instance=obj, using=self.using

                )

            self.send_post_delete_signals(model, instances)



        # update collected instances

        for model, instances_for_fieldvalues in six.iteritems(self.field_updates):

tests/modeltests/delete/tests.py

+12 −0
Original line number Diff line number Diff line
@@ -229,6 +229,18 @@ class DeletionTests(TestCase): 
        models.signals.post_delete.disconnect(log_post_delete)

        models.signals.post_delete.disconnect(log_pre_delete)



    def test_relational_post_delete_signals_happen_before_parent_object(self):

        def log_post_delete(instance, **kwargs):

            self.assertTrue(R.objects.filter(pk=instance.r_id))



        models.signals.post_delete.connect(log_post_delete, sender=S)



        r = R.objects.create(pk=1)

        S.objects.create(pk=1, r=r)

        r.delete()



        models.signals.post_delete.disconnect(log_post_delete)



    @skipUnlessDBFeature("can_defer_constraint_checks")

    def test_can_defer_constraint_checks(self):

        u = User.objects.create(