Ticket #16128: 16128.4.patch

django/db/models/deletion.py

@@ -202 +202 @@
             for model in models:
                 if model in sorted_models:
                     continue
-                dependencies = self.dependencies.get(model)
+                # Dependencies keys are not proxy models
+                base_model = model._meta.proxy and model._meta.proxy_for_model or model
+                dependencies = self.dependencies.get(base_model)
                 if not (dependencies and dependencies.difference(sorted_models)):
                     sorted_models.append(model)
                     found = True

tests/modeltests/proxy_models/models.py

@@ -5 +5 @@
 providing a modified interface to the data from the base class.
 """
 
+from django.contrib.auth.models import User as AuthUser
 from django.contrib.contenttypes.models import ContentType
 from django.db import models
 
@@ -161 +162 @@
 
 class ProxyImprovement(Improvement):
     class Meta:
-        proxy = True
- No newline at end of file
+        proxy = True
+
+
+class AuthUserProxy(AuthUser):
+    class Meta:
+        proxy = True
+
+class Profile(models.Model):
+    user = models.ForeignKey(AuthUser)

tests/modeltests/proxy_models/tests.py

@@ -11 +11 @@
 from models import UserProxyProxy, Country, State, StateProxy, TrackerUser
 from models import BaseUser, Bug, ProxyTrackerUser, Improvement, ProxyProxyBug
 from models import ProxyBug, ProxyImprovement
+from models import AuthUser, AuthUserProxy, Profile
 
 class ProxyModelTests(TestCase):
     def test_same_manager_queries(self):
@@ -312 +313 @@
         management.call_command('loaddata', 'mypeople.json', verbosity=0, commit=False)
         p = MyPerson.objects.get(pk=100)
         self.assertEqual(p.name, 'Elvis Presley')
+
+    def test_delete_cascade_to_proxy_objects(self):
+        """
+        Test that delete() cascades to proxy objects. Regression for #16128.
+        """
+        proxy_joe = AuthUserProxy.objects.create()
+        joe_s_profile = Profile.objects.create(user=proxy_joe)
+        self.assertEqual(Profile.objects.count(), 1)
+        proxy_joe.delete()
+        self.assertEqual(Profile.objects.count(), 0)