From fea9cb46aacc73cabac883a806ccb7fdc1f979dd Mon Sep 17 00:00:00 2001
From: Paulo <commonzenpython@gmail.com>
Date: Mon, 14 Aug 2017 17:27:25 -0400
Subject: [PATCH] Fixed #28375 -- Fixed KeyError crash on reverse prefetch of a
model with OneToOneField primary key to a non-pk field.
---
django/db/models/fields/related_descriptors.py | 9 ++-------
tests/prefetch_related/models.py | 7 ++++++-
tests/prefetch_related/tests.py | 17 +++++++++++++++++
3 files changed, 25 insertions(+), 8 deletions(-)
diff --git a/django/db/models/fields/related_descriptors.py b/django/db/models/fields/related_descriptors.py
index d65af02f32..189e67fab7 100644
--- a/django/db/models/fields/related_descriptors.py
+++ b/django/db/models/fields/related_descriptors.py
@@ -63,8 +63,6 @@ and two directions (forward and reverse) for a total of six combinations.
``ReverseManyToManyDescriptor``, use ``ManyToManyDescriptor`` instead.
"""
-from operator import attrgetter
-
from django.db import connections, router, transaction
from django.db.models import Q, signals
from django.db.models.query import QuerySet
@@ -334,11 +332,8 @@ class ReverseOneToOneDescriptor:
queryset = self.get_queryset()
queryset._add_hints(instance=instances[0])
- rel_obj_attr = attrgetter(self.related.field.attname)
-
- def instance_attr(obj):
- return obj.pk
-
+ rel_obj_attr = self.related.field.get_local_related_value
+ instance_attr = self.related.field.get_foreign_related_value
instances_dict = {instance_attr(inst): inst for inst in instances}
query = {'%s__in' % self.related.field.name: instances}
queryset = queryset.filter(**query)
diff --git a/tests/prefetch_related/models.py b/tests/prefetch_related/models.py
index 08e62c26e0..68fdc2686d 100644
--- a/tests/prefetch_related/models.py
+++ b/tests/prefetch_related/models.py
@@ -65,7 +65,12 @@ class BookWithYear(Book):
class Bio(models.Model):
- author = models.OneToOneField(Author, models.CASCADE)
+ author = models.OneToOneField(
+ Author,
+ models.CASCADE,
+ primary_key=True,
+ to_field='name',
+ )
books = models.ManyToManyField(Book, blank=True)
diff --git a/tests/prefetch_related/tests.py b/tests/prefetch_related/tests.py
index 85de08b184..36d60ea1f4 100644
--- a/tests/prefetch_related/tests.py
+++ b/tests/prefetch_related/tests.py
@@ -81,6 +81,23 @@ class PrefetchRelatedTests(TestCase):
with self.assertRaises(BookWithYear.DoesNotExist):
book.bookwithyear
+ def test_onetoone_reverse_with_to_field_pk(self):
+ """
+ A model (Bio) with a OneToOneField primary key (author) that references
+ a non-pk field (name) on the related model (Author) is prefetchable.
+ """
+ Bio.objects.bulk_create([
+ Bio(author=self.author1),
+ Bio(author=self.author2),
+ Bio(author=self.author3),
+ ])
+ authors = Author.objects.filter(
+ name__in=[self.author1, self.author2, self.author3],
+ ).prefetch_related('bio')
+ with self.assertNumQueries(2):
+ for author in authors:
+ self.assertEqual(author.name, author.bio.author.name)
+
def test_survives_clone(self):
with self.assertNumQueries(2):
[list(b.first_time_authors.all())