diff options
| -rw-r--r-- | django/db/models/fields/related.py | 35 | ||||
| -rw-r--r-- | tests/one_to_one/tests.py | 4 | ||||
| -rw-r--r-- | tests/reverse_single_related/tests.py | 13 |
3 files changed, 45 insertions, 7 deletions
diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py index 5bfb1022a8..87404ed931 100644 --- a/django/db/models/fields/related.py +++ b/django/db/models/fields/related.py @@ -156,6 +156,16 @@ class SingleRelatedObjectDescriptor(six.with_metaclass(RenameRelatedObjectDescri self.related = related self.cache_name = related.get_cache_name() + @cached_property + def RelatedObjectDoesNotExist(self): + # The exception isn't created at initialization time for the sake of + # consistency with `ReverseSingleRelatedObjectDescriptor`. + return type( + str('RelatedObjectDoesNotExist'), + (self.related.model.DoesNotExist, AttributeError), + {} + ) + def is_cached(self, instance): return hasattr(instance, self.cache_name) @@ -200,9 +210,12 @@ class SingleRelatedObjectDescriptor(six.with_metaclass(RenameRelatedObjectDescri setattr(rel_obj, self.related.field.get_cache_name(), instance) setattr(instance, self.cache_name, rel_obj) if rel_obj is None: - raise self.related.model.DoesNotExist("%s has no %s." % ( - instance.__class__.__name__, - self.related.get_accessor_name())) + raise self.RelatedObjectDoesNotExist( + "%s has no %s." % ( + instance.__class__.__name__, + self.related.get_accessor_name() + ) + ) else: return rel_obj @@ -255,6 +268,17 @@ class ReverseSingleRelatedObjectDescriptor(six.with_metaclass(RenameRelatedObjec self.field = field_with_rel self.cache_name = self.field.get_cache_name() + @cached_property + def RelatedObjectDoesNotExist(self): + # The exception can't be created at initialization time since the + # related model might not be resolved yet; `rel.to` might still be + # a string model reference. + return type( + str('RelatedObjectDoesNotExist'), + (self.field.rel.to.DoesNotExist, AttributeError), + {} + ) + def is_cached(self, instance): return hasattr(instance, self.cache_name) @@ -321,8 +345,9 @@ class ReverseSingleRelatedObjectDescriptor(six.with_metaclass(RenameRelatedObjec setattr(rel_obj, self.field.related.get_cache_name(), instance) setattr(instance, self.cache_name, rel_obj) if rel_obj is None and not self.field.null: - raise self.field.rel.to.DoesNotExist( - "%s has no %s." % (self.field.model.__name__, self.field.name)) + raise self.RelatedObjectDoesNotExist( + "%s has no %s." % (self.field.model.__name__, self.field.name) + ) else: return rel_obj 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')) |