Fixed #7853 -- Fixed another case of deleting inherited models with foreign key

references. Thanks to Russell for the test case that demonstrated the problem.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@8128 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/query.py

@@ -835,11 +835,15 @@ def delete_objects(seen_objs):
         del_query.delete_batch_related(pk_list)
 
         update_query = sql.UpdateQuery(cls, connection)
-        for field in cls._meta.fields:
+        for field, model in cls._meta.get_fields_with_model():
             if (field.rel and field.null and field.rel.to in seen_objs and
                     filter(lambda f: f.column == field.column,
                     field.rel.to._meta.fields)):
-                update_query.clear_related(field, pk_list)
+                if model:
+                    sql.UpdateQuery(model, connection).clear_related(field,
+                            pk_list)
+                else:
+                    update_query.clear_related(field, pk_list)
 
     # Now delete the actual data.
     for cls in ordered_classes:

tests/regressiontests/model_inheritance_regress/models.py

@@ -52,7 +52,12 @@ class Parent(models.Model):
 class Child(Parent):
     name = models.CharField(max_length=10)
 
+class SelfRefParent(models.Model):
+    parent_data = models.IntegerField()
+    self_data = models.ForeignKey('self', null=True)
 
+class SelfRefChild(SelfRefParent):
+    child_data = models.IntegerField()
 
 __test__ = {'API_TESTS':"""
 # Regression for #7350, #7202
@@ -182,4 +187,11 @@ True
 >>> Supplier.objects.filter(restaurant=Restaurant(name='xx', address='yy'))
 []
 
+# Regression test for #7853
+# If the parent class has a self-referential link, make sure that any updates
+# to that link via the child update the right table.
+
+>>> obj = SelfRefChild.objects.create(child_data=37, parent_data=42)
+>>> obj.delete()
+
 """}