[1.8.x] Fixed #25685 -- Fixed a duplicate query regression on deletion of proxied models.

Thanks to Trac alias ppetrid for the report and Tim for the review.

2 files changed, 17 insertions, 0 deletions

diff --git a/tests/delete/models.py b/tests/delete/models.py
index 408b6b83f8..8deb65c315 100644
--- a/tests/delete/models.py
+++ b/tests/delete/models.py
@@ -98,6 +98,12 @@ class Avatar(models.Model):
     desc = models.TextField(null=True)
 
 
+# This model is used to test a duplicate query regression (#25685)
+class AvatarProxy(Avatar):
+    class Meta:
+        proxy = True
+
+
 class User(models.Model):
     avatar = models.ForeignKey(Avatar, null=True)
 
diff --git a/tests/delete/tests.py b/tests/delete/tests.py
index 6c7c800483..a2b910ff5d 100644
--- a/tests/delete/tests.py
+++ b/tests/delete/tests.py
@@ -349,6 +349,17 @@ class DeletionTests(TestCase):
         self.assertFalse(S.objects.exists())
         self.assertFalse(T.objects.exists())
 
+    def test_proxied_model_duplicate_queries(self):
+        """
+        #25685 - Deleting instances of a model with existing proxy
+        classes should not issue multiple queries during cascade
+        deletion of referring models.
+        """
+        avatar = Avatar.objects.create()
+        # One query for the Avatar table and a second for the User one.
+        with self.assertNumQueries(2):
+            avatar.delete()
+
 
 class FastDeleteTests(TestCase):