Refs #27222 -- Restored Model.save()'s refreshing of db_returning fields even if a value is set.

The logic could likely be adjusted to assign the pre_save value in most cases
to avoid the database transit but it could break in subtle ways so it's not
worth the complexity it would require.

Regression in 94680437a45a71c70ca8bd2e68b72aa1e2eff337.

Co-authored-by: Tim Graham <timograham@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/tests/basic/tests.py b/tests/basic/tests.py
index 38e7278210..38d7d2a3d6 100644
--- a/tests/basic/tests.py
+++ b/tests/basic/tests.py
@@ -215,6 +215,14 @@ class ModelInstanceCreationTests(TestCase):
         with self.assertNumQueries(1):
             PrimaryKeyWithFalseyDbDefault().save()
 
+    def test_auto_field_with_value_refreshed(self):
+        """
+        An auto field must be refreshed by Model.save() even when a value is
+        set because the database may return a value of a different type.
+        """
+        a = Article.objects.create(pk="123456", pub_date=datetime(2025, 9, 16))
+        self.assertEqual(a.pk, 123456)
+
 
 class ModelTest(TestCase):
     def test_objects_attribute_is_only_available_on_the_class_itself(self):