Fixed #29260 -- Skipped an UPDATE when adding a model instance with primary key that has a default.

1 files changed, 9 insertions, 1 deletions

diff --git a/tests/basic/tests.py b/tests/basic/tests.py
index b29dda64f7..89f6048c96 100644
--- a/tests/basic/tests.py
+++ b/tests/basic/tests.py
@@ -10,7 +10,10 @@ from django.test import (
 )
 from django.utils.translation import gettext_lazy
 
-from .models import Article, ArticleSelectOnSave, FeaturedArticle, SelfRef
+from .models import (
+    Article, ArticleSelectOnSave, FeaturedArticle, PrimaryKeyWithDefault,
+    SelfRef,
+)
 
 
 class ModelInstanceCreationTests(TestCase):
@@ -130,6 +133,11 @@ class ModelInstanceCreationTests(TestCase):
         # ... but there will often be more efficient ways if that is all you need:
         self.assertTrue(Article.objects.filter(id=a.id).exists())
 
+    def test_save_primary_with_default(self):
+        # An UPDATE attempt is skipped when a primary key has default.
+        with self.assertNumQueries(1):
+            PrimaryKeyWithDefault().save()
+
 
 class ModelTest(TestCase):
     def test_objects_attribute_is_only_available_on_the_class_itself(self):