Fixed #14270 - related manager classes should be cached

Thanks to Alex Gaynor for the report and initial patch, and mrmachine for
more work on it.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16916 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 24 insertions, 0 deletions

diff --git a/tests/modeltests/many_to_one/tests.py b/tests/modeltests/many_to_one/tests.py
index 9f60c21f47..4f561b40ca 100644
--- a/tests/modeltests/many_to_one/tests.py
+++ b/tests/modeltests/many_to_one/tests.py
@@ -399,3 +399,13 @@ class ManyToOneTests(TestCase):
         self.assertEqual(repr(a3),
                          repr(Article.objects.get(reporter_id=self.r2.id,
                                              pub_date=datetime(2011, 5, 7))))
+
+    def test_manager_class_caching(self):
+        r1 = Reporter.objects.create(first_name='Mike')
+        r2 = Reporter.objects.create(first_name='John')
+
+        # Same twice
+        self.assertTrue(r1.article_set.__class__ is r1.article_set.__class__)
+
+        # Same as each other
+        self.assertTrue(r1.article_set.__class__ is r2.article_set.__class__)
diff --git a/tests/regressiontests/m2m_regress/tests.py b/tests/regressiontests/m2m_regress/tests.py
index 7bf2381a91..9ae888a6ce 100644
--- a/tests/regressiontests/m2m_regress/tests.py
+++ b/tests/regressiontests/m2m_regress/tests.py
@@ -73,3 +73,17 @@ class M2MRegressionTests(TestCase):
 
         self.assertQuerysetEqual(c1.tags.all(), ["<Tag: t1>", "<Tag: t2>"])
         self.assertQuerysetEqual(t1.tag_collections.all(), ["<TagCollection: c1>"])
+
+    def test_manager_class_caching(self):
+        e1 = Entry.objects.create()
+        e2 = Entry.objects.create()
+        t1 = Tag.objects.create()
+        t2 = Tag.objects.create()
+
+        # Get same manager twice in a row:
+        self.assertTrue(t1.entry_set.__class__ is t1.entry_set.__class__)
+        self.assertTrue(e1.topics.__class__ is e1.topics.__class__)
+
+        # Get same manager for different instances
+        self.assertTrue(e1.topics.__class__ is e2.topics.__class__)
+        self.assertTrue(t1.entry_set.__class__ is t2.entry_set.__class__)