Fixed #25354 -- Added class/app_label interpolation for related_query_name.

tests/model_inheritance/models.py

@@ -56,7 +56,12 @@ class Post(models.Model):
 
 @python_2_unicode_compatible
 class Attachment(models.Model):
-    post = models.ForeignKey(Post, models.CASCADE, related_name='attached_%(class)s_set')
+    post = models.ForeignKey(
+        Post,
+        models.CASCADE,
+        related_name='attached_%(class)s_set',
+        related_query_name='attached_%(app_label)s_%(class)ss',
+    )
     content = models.TextField()
 
     class Meta:

tests/model_inheritance/tests.py

@@ -72,6 +72,15 @@ class ModelInheritanceTests(TestCase):
             AttributeError, getattr, post, "attached_%(class)s_set"
         )
 
+    def test_model_with_distinct_related_query_name(self):
+        self.assertQuerysetEqual(Post.objects.filter(attached_model_inheritance_comments__is_spam=True), [])
+
+        # The Post model doesn't have a related query accessor based on
+        # related_name (attached_comment_set).
+        msg = "Cannot resolve keyword 'attached_comment_set' into field."
+        with self.assertRaisesMessage(FieldError, msg):
+            Post.objects.filter(attached_comment_set__is_spam=True)
+
     def test_meta_fields_and_ordering(self):
         # Make sure Restaurant and ItalianRestaurant have the right fields in
         # the right order.