Fixed #21563 -- Single related object descriptors should work with `hasattr`.

Thanks to Aymeric Augustin for the review and Trac alias monkut for the report.

2 files changed, 15 insertions, 2 deletions

diff --git a/tests/one_to_one/tests.py b/tests/one_to_one/tests.py
index 84ada2cc51..d5d955b08e 100644
--- a/tests/one_to_one/tests.py
+++ b/tests/one_to_one/tests.py
@@ -25,6 +25,10 @@ class OneToOneTests(TestCase):
         # p2 doesn't have an associated restaurant.
         with self.assertRaisesMessage(Restaurant.DoesNotExist, 'Place has no restaurant'):
             self.p2.restaurant
+        # The exception raised on attribute access when a related object
+        # doesn't exist should be an instance of a subclass of `AttributeError`
+        # refs #21563
+        self.assertFalse(hasattr(self.p2, 'restaurant'))
 
     def test_setter(self):
         # Set the place using assignment notation. Because place is the primary
diff --git a/tests/reverse_single_related/tests.py b/tests/reverse_single_related/tests.py
index fd1a5196fe..2a8b96ddbc 100644
--- a/tests/reverse_single_related/tests.py
+++ b/tests/reverse_single_related/tests.py
@@ -33,5 +33,14 @@ class ReverseSingleRelatedTests(TestCase):
         # of the "bare" queryset. Usually you'd define this as a property on the class,
         # but this approximates that in a way that's easier in tests.
         Source.objects.use_for_related_fields = True
-        private_item = Item.objects.get(pk=private_item.pk)
-        self.assertRaises(Source.DoesNotExist, lambda: private_item.source)
+        try:
+            private_item = Item.objects.get(pk=private_item.pk)
+            self.assertRaises(Source.DoesNotExist, lambda: private_item.source)
+        finally:
+            Source.objects.use_for_related_fields = False
+
+    def test_hasattr_single_related(self):
+        # The exception raised on attribute access when a related object
+        # doesn't exist should be an instance of a subclass of `AttributeError`
+        # refs #21563
+        self.assertFalse(hasattr(Item(), 'source'))