Fixed #30501 -- Preventing QuerySet.reverse() from mutating expressions in QuerySet.order_by and Meta.ordering.

1 files changed, 31 insertions, 7 deletions

diff --git a/tests/ordering/tests.py b/tests/ordering/tests.py
index f0c4bba999..1466d350a1 100644
--- a/tests/ordering/tests.py
+++ b/tests/ordering/tests.py
@@ -211,6 +211,15 @@ class OrderingTests(TestCase):
         qs1 = Article.objects.order_by(F('headline').asc())
         qs2 = qs1.reverse()
         self.assertQuerysetEqual(
+            qs2, [
+                'Article 4',
+                'Article 3',
+                'Article 2',
+                'Article 1',
+            ],
+            attrgetter('headline'),
+        )
+        self.assertQuerysetEqual(
             qs1, [
                 "Article 1",
                 "Article 2",
@@ -219,14 +228,29 @@ class OrderingTests(TestCase):
             ],
             attrgetter("headline")
         )
+
+    def test_reverse_meta_ordering_pure(self):
+        Article.objects.create(
+            headline='Article 5',
+            pub_date=datetime(2005, 7, 30),
+            author=self.author_1,
+            second_author=self.author_2,
+        )
+        Article.objects.create(
+            headline='Article 5',
+            pub_date=datetime(2005, 7, 30),
+            author=self.author_2,
+            second_author=self.author_1,
+        )
         self.assertQuerysetEqual(
-            qs2, [
-                "Article 4",
-                "Article 3",
-                "Article 2",
-                "Article 1",
-            ],
-            attrgetter("headline")
+            Article.objects.filter(headline='Article 5').reverse(),
+            ['Name 2', 'Name 1'],
+            attrgetter('author.name'),
+        )
+        self.assertQuerysetEqual(
+            Article.objects.filter(headline='Article 5'),
+            ['Name 1', 'Name 2'],
+            attrgetter('author.name'),
         )
 
     def test_no_reordering_after_slicing(self):