Fixed #18309 - Prefetch related does not work for fkey to multitable inherited model

Thanks to milosu for the report, tests and initial patch.

2 files changed, 14 insertions, 1 deletions

diff --git a/tests/modeltests/prefetch_related/models.py b/tests/modeltests/prefetch_related/models.py
index 1dc034fa6c..589f78c7d3 100644
--- a/tests/modeltests/prefetch_related/models.py
+++ b/tests/modeltests/prefetch_related/models.py
@@ -68,6 +68,9 @@ class Reader(models.Model):
     class Meta:
         ordering = ['id']
 
+class BookReview(models.Model):
+    book = models.ForeignKey(BookWithYear)
+    notes = models.TextField(null=True, blank=True)
 
 ## Models for default manager tests
 
diff --git a/tests/modeltests/prefetch_related/tests.py b/tests/modeltests/prefetch_related/tests.py
index 5cd42a75c0..b21244b6d9 100644
--- a/tests/modeltests/prefetch_related/tests.py
+++ b/tests/modeltests/prefetch_related/tests.py
@@ -7,7 +7,7 @@ from django.test.utils import override_settings
 
 from .models import (Author, Book, Reader, Qualification, Teacher, Department,
     TaggedItem, Bookmark, AuthorAddress, FavoriteAuthors, AuthorWithAge,
-    BookWithYear, Person, House, Room, Employee, Comment)
+    BookWithYear, BookReview, Person, House, Room, Employee, Comment)
 
 
 class PrefetchRelatedTests(TestCase):
@@ -335,6 +335,10 @@ class MultiTableInheritanceTest(TestCase):
         self.authorAddress = AuthorAddress.objects.create(
             author=self.author1, address='SomeStreet 1')
         self.book2.aged_authors.add(self.author2, self.author3)
+        self.br1 = BookReview.objects.create(
+            book=self.book1, notes="review book1")
+        self.br2 = BookReview.objects.create(
+            book=self.book2, notes="review book2")
 
     def test_foreignkey(self):
         with self.assertNumQueries(2):
@@ -343,6 +347,12 @@ class MultiTableInheritanceTest(TestCase):
                          for obj in qs]
         self.assertEqual(addresses, [[unicode(self.authorAddress)], [], []])
 
+    def test_foreignkey_to_inherited(self):
+        with self.assertNumQueries(2):
+            qs = BookReview.objects.prefetch_related('book')
+            titles = [obj.book.title for obj in qs]
+        self.assertEquals(titles, ["Poems", "More poems"])
+
     def test_m2m_to_inheriting_model(self):
         qs = AuthorWithAge.objects.prefetch_related('books_with_year')
         with self.assertNumQueries(2):