django/tests/generic_relations/tests.py

656 lines
27 KiB
Python

from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import FieldError
from django.db import IntegrityError
from django.db.models import Q
from django.test import SimpleTestCase, TestCase
from .models import (
AllowsNullGFK, Animal, Carrot, Comparison, ConcreteRelatedModel,
ForConcreteModelModel, ForProxyModelModel, Gecko, ManualPK, Mineral,
ProxyRelatedModel, Rock, TaggedItem, ValuableRock, ValuableTaggedItem,
Vegetable,
)
class GenericRelationsTests(TestCase):
@classmethod
def setUpTestData(cls):
cls.lion = Animal.objects.create(common_name='Lion', latin_name='Panthera leo')
cls.platypus = Animal.objects.create(
common_name='Platypus',
latin_name='Ornithorhynchus anatinus',
)
Vegetable.objects.create(name="Eggplant", is_yucky=True)
cls.bacon = Vegetable.objects.create(name='Bacon', is_yucky=False)
cls.quartz = Mineral.objects.create(name='Quartz', hardness=7)
# Tagging stuff.
cls.fatty = cls.bacon.tags.create(tag='fatty')
cls.salty = cls.bacon.tags.create(tag='salty')
cls.yellow = cls.lion.tags.create(tag='yellow')
cls.hairy = cls.lion.tags.create(tag='hairy')
def comp_func(self, obj):
# Original list of tags:
return obj.tag, obj.content_type.model_class(), obj.object_id
def test_generic_update_or_create_when_created(self):
"""
Should be able to use update_or_create from the generic related manager
to create a tag. Refs #23611.
"""
count = self.bacon.tags.count()
tag, created = self.bacon.tags.update_or_create(tag='stinky')
self.assertTrue(created)
self.assertEqual(count + 1, self.bacon.tags.count())
def test_generic_update_or_create_when_updated(self):
"""
Should be able to use update_or_create from the generic related manager
to update a tag. Refs #23611.
"""
count = self.bacon.tags.count()
tag = self.bacon.tags.create(tag='stinky')
self.assertEqual(count + 1, self.bacon.tags.count())
tag, created = self.bacon.tags.update_or_create(defaults={'tag': 'juicy'}, id=tag.id)
self.assertFalse(created)
self.assertEqual(count + 1, self.bacon.tags.count())
self.assertEqual(tag.tag, 'juicy')
def test_generic_get_or_create_when_created(self):
"""
Should be able to use get_or_create from the generic related manager
to create a tag. Refs #23611.
"""
count = self.bacon.tags.count()
tag, created = self.bacon.tags.get_or_create(tag='stinky')
self.assertTrue(created)
self.assertEqual(count + 1, self.bacon.tags.count())
def test_generic_get_or_create_when_exists(self):
"""
Should be able to use get_or_create from the generic related manager
to get a tag. Refs #23611.
"""
count = self.bacon.tags.count()
tag = self.bacon.tags.create(tag="stinky")
self.assertEqual(count + 1, self.bacon.tags.count())
tag, created = self.bacon.tags.get_or_create(id=tag.id, defaults={'tag': 'juicy'})
self.assertFalse(created)
self.assertEqual(count + 1, self.bacon.tags.count())
# shouldn't had changed the tag
self.assertEqual(tag.tag, 'stinky')
def test_generic_relations_m2m_mimic(self):
"""
Objects with declared GenericRelations can be tagged directly -- the
API mimics the many-to-many API.
"""
self.assertSequenceEqual(self.lion.tags.all(), [self.hairy, self.yellow])
self.assertSequenceEqual(self.bacon.tags.all(), [self.fatty, self.salty])
def test_access_content_object(self):
"""
Test accessing the content object like a foreign key.
"""
tagged_item = TaggedItem.objects.get(tag="salty")
self.assertEqual(tagged_item.content_object, self.bacon)
def test_query_content_object(self):
qs = TaggedItem.objects.filter(
animal__isnull=False).order_by('animal__common_name', 'tag')
self.assertSequenceEqual(qs, [self.hairy, self.yellow])
mpk = ManualPK.objects.create(id=1)
mpk.tags.create(tag='mpk')
qs = TaggedItem.objects.filter(
Q(animal__isnull=False) | Q(manualpk__id=1)).order_by('tag')
self.assertQuerysetEqual(
qs, ["hairy", "mpk", "yellow"], lambda x: x.tag)
def test_exclude_generic_relations(self):
"""
Test lookups over an object without GenericRelations.
"""
# Recall that the Mineral class doesn't have an explicit GenericRelation
# defined. That's OK, because you can create TaggedItems explicitly.
# However, excluding GenericRelations means your lookups have to be a
# bit more explicit.
shiny = TaggedItem.objects.create(content_object=self.quartz, tag="shiny")
clearish = TaggedItem.objects.create(content_object=self.quartz, tag="clearish")
ctype = ContentType.objects.get_for_model(self.quartz)
q = TaggedItem.objects.filter(
content_type__pk=ctype.id, object_id=self.quartz.id
)
self.assertSequenceEqual(q, [clearish, shiny])
def test_access_via_content_type(self):
"""
Test lookups through content type.
"""
self.lion.delete()
self.platypus.tags.create(tag="fatty")
ctype = ContentType.objects.get_for_model(self.platypus)
self.assertSequenceEqual(
Animal.objects.filter(tags__content_type=ctype),
[self.platypus],
)
def test_set_foreign_key(self):
"""
You can set a generic foreign key in the way you'd expect.
"""
tag1 = TaggedItem.objects.create(content_object=self.quartz, tag="shiny")
tag1.content_object = self.platypus
tag1.save()
self.assertSequenceEqual(self.platypus.tags.all(), [tag1])
def test_queries_across_generic_relations(self):
"""
Queries across generic relations respect the content types. Even though
there are two TaggedItems with a tag of "fatty", this query only pulls
out the one with the content type related to Animals.
"""
self.assertSequenceEqual(
Animal.objects.order_by('common_name'),
[self.lion, self.platypus],
)
def test_queries_content_type_restriction(self):
"""
Create another fatty tagged instance with different PK to ensure there
is a content type restriction in the generated queries below.
"""
mpk = ManualPK.objects.create(id=self.lion.pk)
mpk.tags.create(tag="fatty")
self.platypus.tags.create(tag="fatty")
self.assertSequenceEqual(
Animal.objects.filter(tags__tag='fatty'),
[self.platypus],
)
self.assertSequenceEqual(
Animal.objects.exclude(tags__tag='fatty'),
[self.lion],
)
def test_object_deletion_with_generic_relation(self):
"""
If you delete an object with an explicit Generic relation, the related
objects are deleted when the source object is deleted.
"""
self.assertQuerysetEqual(TaggedItem.objects.all(), [
('fatty', Vegetable, self.bacon.pk),
('hairy', Animal, self.lion.pk),
('salty', Vegetable, self.bacon.pk),
('yellow', Animal, self.lion.pk)
],
self.comp_func
)
self.lion.delete()
self.assertQuerysetEqual(TaggedItem.objects.all(), [
('fatty', Vegetable, self.bacon.pk),
('salty', Vegetable, self.bacon.pk),
],
self.comp_func
)
def test_object_deletion_without_generic_relation(self):
"""
If Generic Relation is not explicitly defined, any related objects
remain after deletion of the source object.
"""
TaggedItem.objects.create(content_object=self.quartz, tag="clearish")
quartz_pk = self.quartz.pk
self.quartz.delete()
self.assertQuerysetEqual(TaggedItem.objects.all(), [
('clearish', Mineral, quartz_pk),
('fatty', Vegetable, self.bacon.pk),
('hairy', Animal, self.lion.pk),
('salty', Vegetable, self.bacon.pk),
('yellow', Animal, self.lion.pk),
],
self.comp_func
)
def test_tag_deletion_related_objects_unaffected(self):
"""
If you delete a tag, the objects using the tag are unaffected (other
than losing a tag).
"""
ctype = ContentType.objects.get_for_model(self.lion)
tag = TaggedItem.objects.get(
content_type__pk=ctype.id, object_id=self.lion.id, tag="hairy")
tag.delete()
self.assertSequenceEqual(self.lion.tags.all(), [self.yellow])
self.assertQuerysetEqual(TaggedItem.objects.all(), [
('fatty', Vegetable, self.bacon.pk),
('salty', Vegetable, self.bacon.pk),
('yellow', Animal, self.lion.pk)
],
self.comp_func
)
def test_add_bulk(self):
bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
t1 = TaggedItem.objects.create(content_object=self.quartz, tag="shiny")
t2 = TaggedItem.objects.create(content_object=self.quartz, tag="clearish")
# One update() query.
with self.assertNumQueries(1):
bacon.tags.add(t1, t2)
self.assertEqual(t1.content_object, bacon)
self.assertEqual(t2.content_object, bacon)
def test_add_bulk_false(self):
bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
t1 = TaggedItem.objects.create(content_object=self.quartz, tag="shiny")
t2 = TaggedItem.objects.create(content_object=self.quartz, tag="clearish")
# One save() for each object.
with self.assertNumQueries(2):
bacon.tags.add(t1, t2, bulk=False)
self.assertEqual(t1.content_object, bacon)
self.assertEqual(t2.content_object, bacon)
def test_add_rejects_unsaved_objects(self):
t1 = TaggedItem(content_object=self.quartz, tag="shiny")
msg = "<TaggedItem: shiny> instance isn't saved. Use bulk=False or save the object first."
with self.assertRaisesMessage(ValueError, msg):
self.bacon.tags.add(t1)
def test_add_rejects_wrong_instances(self):
msg = "'TaggedItem' instance expected, got <Animal: Lion>"
with self.assertRaisesMessage(TypeError, msg):
self.bacon.tags.add(self.lion)
def test_set(self):
bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
fatty = bacon.tags.create(tag="fatty")
salty = bacon.tags.create(tag="salty")
bacon.tags.set([fatty, salty])
self.assertSequenceEqual(bacon.tags.all(), [fatty, salty])
bacon.tags.set([fatty])
self.assertSequenceEqual(bacon.tags.all(), [fatty])
bacon.tags.set([])
self.assertSequenceEqual(bacon.tags.all(), [])
bacon.tags.set([fatty, salty], bulk=False, clear=True)
self.assertSequenceEqual(bacon.tags.all(), [fatty, salty])
bacon.tags.set([fatty], bulk=False, clear=True)
self.assertSequenceEqual(bacon.tags.all(), [fatty])
bacon.tags.set([], clear=True)
self.assertSequenceEqual(bacon.tags.all(), [])
def test_assign(self):
bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
fatty = bacon.tags.create(tag="fatty")
salty = bacon.tags.create(tag="salty")
bacon.tags.set([fatty, salty])
self.assertSequenceEqual(bacon.tags.all(), [fatty, salty])
bacon.tags.set([fatty])
self.assertSequenceEqual(bacon.tags.all(), [fatty])
bacon.tags.set([])
self.assertSequenceEqual(bacon.tags.all(), [])
def test_assign_with_queryset(self):
# Querysets used in reverse GFK assignments are pre-evaluated so their
# value isn't affected by the clearing operation
# in ManyRelatedManager.set() (#19816).
bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
bacon.tags.create(tag="fatty")
bacon.tags.create(tag="salty")
self.assertEqual(2, bacon.tags.count())
qs = bacon.tags.filter(tag="fatty")
bacon.tags.set(qs)
self.assertEqual(1, bacon.tags.count())
self.assertEqual(1, qs.count())
def test_clear(self):
self.assertSequenceEqual(
TaggedItem.objects.order_by('tag'),
[self.fatty, self.hairy, self.salty, self.yellow],
)
self.bacon.tags.clear()
self.assertSequenceEqual(self.bacon.tags.all(), [])
self.assertSequenceEqual(
TaggedItem.objects.order_by('tag'),
[self.hairy, self.yellow],
)
def test_remove(self):
self.assertSequenceEqual(
TaggedItem.objects.order_by('tag'),
[self.fatty, self.hairy, self.salty, self.yellow],
)
self.bacon.tags.remove(self.fatty)
self.assertSequenceEqual(self.bacon.tags.all(), [self.salty])
self.assertSequenceEqual(
TaggedItem.objects.order_by('tag'),
[self.hairy, self.salty, self.yellow],
)
def test_generic_relation_related_name_default(self):
# GenericRelation isn't usable from the reverse side by default.
msg = (
"Cannot resolve keyword 'vegetable' into field. Choices are: "
"animal, content_object, content_type, content_type_id, id, "
"manualpk, object_id, tag, valuabletaggeditem"
)
with self.assertRaisesMessage(FieldError, msg):
TaggedItem.objects.filter(vegetable__isnull=True)
def test_multiple_gfk(self):
# Simple tests for multiple GenericForeignKeys
# only uses one model, since the above tests should be sufficient.
tiger = Animal.objects.create(common_name="tiger")
cheetah = Animal.objects.create(common_name="cheetah")
bear = Animal.objects.create(common_name="bear")
# Create directly
c1 = Comparison.objects.create(
first_obj=cheetah, other_obj=tiger, comparative="faster"
)
c2 = Comparison.objects.create(
first_obj=tiger, other_obj=cheetah, comparative="cooler"
)
# Create using GenericRelation
c3 = tiger.comparisons.create(other_obj=bear, comparative="cooler")
c4 = tiger.comparisons.create(other_obj=cheetah, comparative="stronger")
self.assertSequenceEqual(cheetah.comparisons.all(), [c1])
# Filtering works
self.assertCountEqual(
tiger.comparisons.filter(comparative='cooler'),
[c2, c3],
)
# Filtering and deleting works
subjective = ["cooler"]
tiger.comparisons.filter(comparative__in=subjective).delete()
self.assertCountEqual(Comparison.objects.all(), [c1, c4])
# If we delete cheetah, Comparisons with cheetah as 'first_obj' will be
# deleted since Animal has an explicit GenericRelation to Comparison
# through first_obj. Comparisons with cheetah as 'other_obj' will not
# be deleted.
cheetah.delete()
self.assertSequenceEqual(Comparison.objects.all(), [c4])
def test_gfk_subclasses(self):
# GenericForeignKey should work with subclasses (see #8309)
quartz = Mineral.objects.create(name="Quartz", hardness=7)
valuedtag = ValuableTaggedItem.objects.create(
content_object=quartz, tag="shiny", value=10
)
self.assertEqual(valuedtag.content_object, quartz)
def test_generic_relation_to_inherited_child(self):
# GenericRelations to models that use multi-table inheritance work.
granite = ValuableRock.objects.create(name='granite', hardness=5)
ValuableTaggedItem.objects.create(content_object=granite, tag="countertop", value=1)
self.assertEqual(ValuableRock.objects.filter(tags__value=1).count(), 1)
# We're generating a slightly inefficient query for tags__tag - we
# first join ValuableRock -> TaggedItem -> ValuableTaggedItem, and then
# we fetch tag by joining TaggedItem from ValuableTaggedItem. The last
# join isn't necessary, as TaggedItem <-> ValuableTaggedItem is a
# one-to-one join.
self.assertEqual(ValuableRock.objects.filter(tags__tag="countertop").count(), 1)
granite.delete() # deleting the rock should delete the related tag.
self.assertEqual(ValuableTaggedItem.objects.count(), 0)
def test_gfk_manager(self):
# GenericForeignKey should not use the default manager (which may filter objects) #16048
tailless = Gecko.objects.create(has_tail=False)
tag = TaggedItem.objects.create(content_object=tailless, tag="lizard")
self.assertEqual(tag.content_object, tailless)
def test_subclasses_with_gen_rel(self):
"""
Concrete model subclasses with generic relations work
correctly (ticket 11263).
"""
granite = Rock.objects.create(name='granite', hardness=5)
TaggedItem.objects.create(content_object=granite, tag="countertop")
self.assertEqual(Rock.objects.get(tags__tag="countertop"), granite)
def test_subclasses_with_parent_gen_rel(self):
"""
Generic relations on a base class (Vegetable) work correctly in
subclasses (Carrot).
"""
bear = Carrot.objects.create(name='carrot')
TaggedItem.objects.create(content_object=bear, tag='orange')
self.assertEqual(Carrot.objects.get(tags__tag='orange'), bear)
def test_get_or_create(self):
# get_or_create should work with virtual fields (content_object)
quartz = Mineral.objects.create(name="Quartz", hardness=7)
tag, created = TaggedItem.objects.get_or_create(tag="shiny", defaults={'content_object': quartz})
self.assertTrue(created)
self.assertEqual(tag.tag, "shiny")
self.assertEqual(tag.content_object.id, quartz.id)
def test_update_or_create_defaults(self):
# update_or_create should work with virtual fields (content_object)
quartz = Mineral.objects.create(name="Quartz", hardness=7)
diamond = Mineral.objects.create(name="Diamond", hardness=7)
tag, created = TaggedItem.objects.update_or_create(tag="shiny", defaults={'content_object': quartz})
self.assertTrue(created)
self.assertEqual(tag.content_object.id, quartz.id)
tag, created = TaggedItem.objects.update_or_create(tag="shiny", defaults={'content_object': diamond})
self.assertFalse(created)
self.assertEqual(tag.content_object.id, diamond.id)
def test_query_content_type(self):
msg = "Field 'content_object' does not generate an automatic reverse relation"
with self.assertRaisesMessage(FieldError, msg):
TaggedItem.objects.get(content_object='')
def test_unsaved_instance_on_generic_foreign_key(self):
"""
Assigning an unsaved object to GenericForeignKey should raise an
exception on model.save().
"""
quartz = Mineral(name="Quartz", hardness=7)
with self.assertRaises(IntegrityError):
TaggedItem.objects.create(tag="shiny", content_object=quartz)
def test_cache_invalidation_for_content_type_id(self):
# Create a Vegetable and Mineral with the same id.
new_id = max(Vegetable.objects.order_by('-id')[0].id,
Mineral.objects.order_by('-id')[0].id) + 1
broccoli = Vegetable.objects.create(id=new_id, name="Broccoli")
diamond = Mineral.objects.create(id=new_id, name="Diamond", hardness=7)
tag = TaggedItem.objects.create(content_object=broccoli, tag="yummy")
tag.content_type = ContentType.objects.get_for_model(diamond)
self.assertEqual(tag.content_object, diamond)
def test_cache_invalidation_for_object_id(self):
broccoli = Vegetable.objects.create(name="Broccoli")
cauliflower = Vegetable.objects.create(name="Cauliflower")
tag = TaggedItem.objects.create(content_object=broccoli, tag="yummy")
tag.object_id = cauliflower.id
self.assertEqual(tag.content_object, cauliflower)
def test_assign_content_object_in_init(self):
spinach = Vegetable(name="spinach")
tag = TaggedItem(content_object=spinach)
self.assertEqual(tag.content_object, spinach)
def test_create_after_prefetch(self):
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [])
weird_tag = platypus.tags.create(tag='weird')
self.assertSequenceEqual(platypus.tags.all(), [weird_tag])
def test_add_after_prefetch(self):
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [])
weird_tag = TaggedItem.objects.create(tag='weird', content_object=platypus)
platypus.tags.add(weird_tag)
self.assertSequenceEqual(platypus.tags.all(), [weird_tag])
def test_remove_after_prefetch(self):
weird_tag = self.platypus.tags.create(tag='weird')
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [weird_tag])
platypus.tags.remove(weird_tag)
self.assertSequenceEqual(platypus.tags.all(), [])
def test_clear_after_prefetch(self):
weird_tag = self.platypus.tags.create(tag='weird')
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [weird_tag])
platypus.tags.clear()
self.assertSequenceEqual(platypus.tags.all(), [])
def test_set_after_prefetch(self):
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [])
furry_tag = TaggedItem.objects.create(tag='furry', content_object=platypus)
platypus.tags.set([furry_tag])
self.assertSequenceEqual(platypus.tags.all(), [furry_tag])
weird_tag = TaggedItem.objects.create(tag='weird', content_object=platypus)
platypus.tags.set([weird_tag])
self.assertSequenceEqual(platypus.tags.all(), [weird_tag])
def test_add_then_remove_after_prefetch(self):
furry_tag = self.platypus.tags.create(tag='furry')
platypus = Animal.objects.prefetch_related('tags').get(pk=self.platypus.pk)
self.assertSequenceEqual(platypus.tags.all(), [furry_tag])
weird_tag = self.platypus.tags.create(tag='weird')
platypus.tags.add(weird_tag)
self.assertSequenceEqual(platypus.tags.all(), [furry_tag, weird_tag])
platypus.tags.remove(weird_tag)
self.assertSequenceEqual(platypus.tags.all(), [furry_tag])
def test_prefetch_related_different_content_types(self):
TaggedItem.objects.create(content_object=self.platypus, tag='prefetch_tag_1')
TaggedItem.objects.create(
content_object=Vegetable.objects.create(name='Broccoli'),
tag='prefetch_tag_2',
)
TaggedItem.objects.create(
content_object=Animal.objects.create(common_name='Bear'),
tag='prefetch_tag_3',
)
qs = TaggedItem.objects.filter(
tag__startswith='prefetch_tag_',
).prefetch_related('content_object', 'content_object__tags')
with self.assertNumQueries(4):
tags = list(qs)
for tag in tags:
self.assertSequenceEqual(tag.content_object.tags.all(), [tag])
def test_prefetch_related_custom_object_id(self):
tiger = Animal.objects.create(common_name='tiger')
cheetah = Animal.objects.create(common_name='cheetah')
Comparison.objects.create(
first_obj=cheetah, other_obj=tiger, comparative='faster',
)
Comparison.objects.create(
first_obj=tiger, other_obj=cheetah, comparative='cooler',
)
qs = Comparison.objects.prefetch_related('first_obj__comparisons')
for comparison in qs:
self.assertSequenceEqual(comparison.first_obj.comparisons.all(), [comparison])
class ProxyRelatedModelTest(TestCase):
def test_default_behavior(self):
"""
The default for for_concrete_model should be True
"""
base = ForConcreteModelModel()
base.obj = rel = ProxyRelatedModel.objects.create()
base.save()
base = ForConcreteModelModel.objects.get(pk=base.pk)
rel = ConcreteRelatedModel.objects.get(pk=rel.pk)
self.assertEqual(base.obj, rel)
def test_works_normally(self):
"""
When for_concrete_model is False, we should still be able to get
an instance of the concrete class.
"""
base = ForProxyModelModel()
base.obj = rel = ConcreteRelatedModel.objects.create()
base.save()
base = ForProxyModelModel.objects.get(pk=base.pk)
self.assertEqual(base.obj, rel)
def test_proxy_is_returned(self):
"""
Instances of the proxy should be returned when
for_concrete_model is False.
"""
base = ForProxyModelModel()
base.obj = ProxyRelatedModel.objects.create()
base.save()
base = ForProxyModelModel.objects.get(pk=base.pk)
self.assertIsInstance(base.obj, ProxyRelatedModel)
def test_query(self):
base = ForProxyModelModel()
base.obj = rel = ConcreteRelatedModel.objects.create()
base.save()
self.assertEqual(rel, ConcreteRelatedModel.objects.get(bases__id=base.id))
def test_query_proxy(self):
base = ForProxyModelModel()
base.obj = rel = ProxyRelatedModel.objects.create()
base.save()
self.assertEqual(rel, ProxyRelatedModel.objects.get(bases__id=base.id))
def test_generic_relation(self):
base = ForProxyModelModel()
base.obj = ProxyRelatedModel.objects.create()
base.save()
base = ForProxyModelModel.objects.get(pk=base.pk)
rel = ProxyRelatedModel.objects.get(pk=base.obj.pk)
self.assertEqual(base, rel.bases.get())
def test_generic_relation_set(self):
base = ForProxyModelModel()
base.obj = ConcreteRelatedModel.objects.create()
base.save()
newrel = ConcreteRelatedModel.objects.create()
newrel.bases.set([base])
newrel = ConcreteRelatedModel.objects.get(pk=newrel.pk)
self.assertEqual(base, newrel.bases.get())
class TestInitWithNoneArgument(SimpleTestCase):
def test_none_allowed(self):
# AllowsNullGFK doesn't require a content_type, so None argument should
# also be allowed.
AllowsNullGFK(content_object=None)
# TaggedItem requires a content_type but initializing with None should
# be allowed.
TaggedItem(content_object=None)