Ticket #17256: ticket-17256-with-tests.diff

django/contrib/contenttypes/tests.py

@@ -44 +44 @@
     def test_lookup_cache(self):
         """
         Make sure that the content type cache (see ContentTypeManager)
-        works correctly. Lookups for a particular content type -- by model or
-        by ID -- should hit the database only on the first lookup.
+        works correctly. Lookups for a particular content type -- by model, ID
+        or natural key -- should hit the database only on the first lookup.
         """
 
         # At this point, a lookup for a ContentType should hit the DB
@@ -53 +53 @@
             ContentType.objects.get_for_model(ContentType)
 
         # A second hit, though, won't hit the DB, nor will a lookup by ID
+        # or natural key
         with self.assertNumQueries(0):
             ct = ContentType.objects.get_for_model(ContentType)
         with self.assertNumQueries(0):
             ContentType.objects.get_for_id(ct.id)
+        with self.assertNumQueries(0):
+            ContentType.objects.get_by_natural_key('contenttypes',
+                                                   'contenttype')
 
         # Once we clear the cache, another lookup will again hit the DB
         ContentType.objects.clear_cache()
         with self.assertNumQueries(1):
             ContentType.objects.get_for_model(ContentType)
 
+        # The same should happen with a lookup by natural key
+        ContentType.objects.clear_cache()
+        with self.assertNumQueries(1):
+            ContentType.objects.get_by_natural_key('contenttypes',
+                                                   'contenttype')
+        # And a second hit shouldn't hit the DB
+        with self.assertNumQueries(0):
+            ContentType.objects.get_by_natural_key('contenttypes',
+                                                   'contenttype')
+
     def test_get_for_models_empty_cache(self):
         # Empty cache.
         with self.assertNumQueries(1):

django/contrib/contenttypes/models.py

@@ -13 +13 @@
             ct = self.__class__._cache[self.db][(app_label, model)]
         except KeyError:
             ct = self.get(app_label=app_label, model=model)
+            self._add_to_cache(self.db, ct)
         return ct
 
     def _get_opts(self, model):