Fixed #14896 -- Ensured that _meta.get_all_related_objects(include_hidden=True) also works correctly with model inheritance.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15248 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/models/options.py

@@ -371,7 +371,7 @@ class Options(object):
         cache = SortedDict()
         parent_list = self.get_parent_list()
         for parent in self.parents:
-            for obj, model in parent._meta.get_all_related_objects_with_model():
+            for obj, model in parent._meta.get_all_related_objects_with_model(include_hidden=True):
                 if (obj.field.creation_counter < 0 or obj.field.rel.parent_link) and obj.model not in parent_list:
                     continue
                 if not model:

tests/regressiontests/delete_regress/models.py

@@ -35,3 +35,12 @@ class PlayedWith(models.Model):
 class PlayedWithNote(models.Model):
     played = models.ForeignKey(PlayedWith)
     note = models.TextField()
+
+class Contact(models.Model):
+    label = models.CharField(max_length=100)
+
+class Email(Contact):
+    email_address = models.EmailField(max_length=100)
+
+class Researcher(models.Model):
+    contacts = models.ManyToManyField(Contact, related_name="research_contacts")

tests/regressiontests/delete_regress/tests.py

@@ -4,7 +4,8 @@ from django.conf import settings
 from django.db import backend, connection, transaction, DEFAULT_DB_ALIAS
 from django.test import TestCase, TransactionTestCase, skipUnlessDBFeature
 
-from models import Book, Award, AwardNote, Person, Child, Toy, PlayedWith, PlayedWithNote
+from models import (Book, Award, AwardNote, Person, Child, Toy, PlayedWith,
+    PlayedWithNote, Contact, Email, Researcher)
 
 
 # Can't run this test under SQLite, because you can't
@@ -62,17 +63,12 @@ class DeleteLockingTest(TransactionTestCase):
         transaction.commit()
         self.assertEqual(1, Book.objects.count())
 
+
 class DeleteCascadeTests(TestCase):
     def test_generic_relation_cascade(self):
         """
-        Test that Django cascades deletes through generic-related
+        Django cascades deletes through generic-related objects to their
-        objects to their reverse relations.
+        reverse relations.
-
-        This might falsely succeed if the database cascades deletes
-        itself immediately; the postgresql_psycopg2 backend does not
-        give such a false success because ForeignKeys are created with
-        DEFERRABLE INITIALLY DEFERRED, so its internal cascade is
-        delayed until transaction commit.
 
         """
         person = Person.objects.create(name='Nelson Mandela')
@@ -87,13 +83,10 @@ class DeleteCascadeTests(TestCase):
 
     def test_fk_to_m2m_through(self):
         """
-        Test that if a M2M relationship has an explicitly-specified
+        If an M2M relationship has an explicitly-specified through model, and
-        through model, and some other model has an FK to that through
+        some other model has an FK to that through model, deletion is cascaded
-        model, deletion is cascaded from one of the participants in
+        from one of the participants in the M2M, to the through model, to its
-        the M2M, to the through model, to its related model.
+        related model.
-
-        Like the above test, this could in theory falsely succeed if
-        the DB cascades deletes itself immediately.
 
         """
         juan = Child.objects.create(name='Juan')
@@ -108,6 +101,24 @@ class DeleteCascadeTests(TestCase):
         # first two asserts just sanity checks, this is the kicker:
         self.assertEquals(PlayedWithNote.objects.count(), 0)
 
+
+class DeleteCascadeTransactionTests(TransactionTestCase):
+    def test_inheritance(self):
+        """
+        Auto-created many-to-many through tables referencing a parent model are
+        correctly found by the delete cascade when a child of that parent is
+        deleted.
+
+        Refs #14896.
+        """
+        r = Researcher.objects.create()
+        email = Email.objects.create(
+            label="office-email", email_address="carl@science.edu"
+        )
+        r.contacts.add(email)
+
+        email.delete()
+
 class LargeDeleteTests(TestCase):
     def test_large_deletes(self):
         "Regression for #13309 -- if the number of objects > chunk size, deletion still occurs"