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django/tests/generic_relations/tests.py
2015-02-06 08:16:28 -05:00

633 lines
26 KiB
Python

from __future__ import unicode_literals
from django import forms
from django.contrib.contenttypes.forms import generic_inlineformset_factory
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import FieldError
from django.db.models import Q
from django.test import TestCase
from django.utils import six
from .models import (
AllowsNullGFK, Animal, Comparison, ConcreteRelatedModel,
ForConcreteModelModel, ForProxyModelModel, Gecko, ManualPK, Mineral,
ProxyRelatedModel, Rock, TaggedItem, ValuableTaggedItem, Vegetable,
)
class GenericRelationsTests(TestCase):
def setUp(self):
self.lion = Animal.objects.create(
common_name="Lion", latin_name="Panthera leo")
self.platypus = Animal.objects.create(
common_name="Platypus", latin_name="Ornithorhynchus anatinus")
Vegetable.objects.create(name="Eggplant", is_yucky=True)
self.bacon = Vegetable.objects.create(name="Bacon", is_yucky=False)
self.quartz = Mineral.objects.create(name="Quartz", hardness=7)
# Tagging stuff.
self.bacon.tags.create(tag="fatty")
self.bacon.tags.create(tag="salty")
self.lion.tags.create(tag="yellow")
self.lion.tags.create(tag="hairy")
# Original list of tags:
self.comp_func = lambda obj: (
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.assertQuerysetEqual(self.lion.tags.all(), [
"<TaggedItem: hairy>",
"<TaggedItem: yellow>"
])
self.assertQuerysetEqual(self.bacon.tags.all(), [
"<TaggedItem: fatty>",
"<TaggedItem: 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.assertQuerysetEqual(
qs, ["<TaggedItem: hairy>", "<TaggedItem: 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.
TaggedItem.objects.create(content_object=self.quartz, tag="shiny")
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.assertQuerysetEqual(q, [
"<TaggedItem: clearish>",
"<TaggedItem: 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.assertQuerysetEqual(
Animal.objects.filter(tags__content_type=ctype),
["<Animal: 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.assertQuerysetEqual(
self.platypus.tags.all(),
["<TaggedItem: shiny>"])
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.assertQuerysetEqual(Animal.objects.order_by('common_name'), [
"<Animal: Lion>",
"<Animal: 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.assertQuerysetEqual(
Animal.objects.filter(tags__tag='fatty'), ["<Animal: Platypus>"])
self.assertQuerysetEqual(
Animal.objects.exclude(tags__tag='fatty'), ["<Animal: 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.assertQuerysetEqual(self.lion.tags.all(), ["<TaggedItem: 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_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.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
"<TaggedItem: salty>",
])
bacon.tags.set([fatty])
self.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
])
bacon.tags.set([])
self.assertQuerysetEqual(bacon.tags.all(), [])
bacon.tags.set([fatty, salty], clear=True)
self.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
"<TaggedItem: salty>",
])
bacon.tags.set([fatty], clear=True)
self.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
])
bacon.tags.set([], clear=True)
self.assertQuerysetEqual(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 = [fatty, salty]
self.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
"<TaggedItem: salty>",
])
bacon.tags = [fatty]
self.assertQuerysetEqual(bacon.tags.all(), [
"<TaggedItem: fatty>",
])
bacon.tags = []
self.assertQuerysetEqual(bacon.tags.all(), [])
def test_assign_with_queryset(self):
# Ensure that querysets used in reverse GFK assignments are pre-evaluated
# so their value isn't affected by the clearing operation in
# ManyRelatedObjectsDescriptor.__set__. Refs #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 = qs
self.assertEqual(1, bacon.tags.count())
self.assertEqual(1, qs.count())
def test_generic_relation_related_name_default(self):
# Test that GenericRelation by default isn't usable from
# the reverse side.
with self.assertRaises(FieldError):
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
Comparison.objects.create(
first_obj=cheetah, other_obj=tiger, comparative="faster"
)
Comparison.objects.create(
first_obj=tiger, other_obj=cheetah, comparative="cooler"
)
# Create using GenericRelation
tiger.comparisons.create(other_obj=bear, comparative="cooler")
tiger.comparisons.create(other_obj=cheetah, comparative="stronger")
self.assertQuerysetEqual(cheetah.comparisons.all(), [
"<Comparison: cheetah is faster than tiger>"
])
# Filtering works
self.assertQuerysetEqual(tiger.comparisons.filter(comparative="cooler"), [
"<Comparison: tiger is cooler than cheetah>",
"<Comparison: tiger is cooler than bear>",
], ordered=False)
# Filtering and deleting works
subjective = ["cooler"]
tiger.comparisons.filter(comparative__in=subjective).delete()
self.assertQuerysetEqual(Comparison.objects.all(), [
"<Comparison: cheetah is faster than tiger>",
"<Comparison: tiger is stronger than cheetah>"
], ordered=False)
# 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.assertQuerysetEqual(Comparison.objects.all(), [
"<Comparison: tiger is stronger than None>"
])
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_inline_formsets(self):
GenericFormSet = generic_inlineformset_factory(TaggedItem, extra=1)
formset = GenericFormSet()
self.assertHTMLEqual(''.join(form.as_p() for form in formset.forms), """<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-tag">Tag:</label> <input id="id_generic_relations-taggeditem-content_type-object_id-0-tag" type="text" name="generic_relations-taggeditem-content_type-object_id-0-tag" maxlength="50" /></p>
<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-DELETE">Delete:</label> <input type="checkbox" name="generic_relations-taggeditem-content_type-object_id-0-DELETE" id="id_generic_relations-taggeditem-content_type-object_id-0-DELETE" /><input type="hidden" name="generic_relations-taggeditem-content_type-object_id-0-id" id="id_generic_relations-taggeditem-content_type-object_id-0-id" /></p>""")
formset = GenericFormSet(instance=Animal())
self.assertHTMLEqual(''.join(form.as_p() for form in formset.forms), """<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-tag">Tag:</label> <input id="id_generic_relations-taggeditem-content_type-object_id-0-tag" type="text" name="generic_relations-taggeditem-content_type-object_id-0-tag" maxlength="50" /></p>
<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-DELETE">Delete:</label> <input type="checkbox" name="generic_relations-taggeditem-content_type-object_id-0-DELETE" id="id_generic_relations-taggeditem-content_type-object_id-0-DELETE" /><input type="hidden" name="generic_relations-taggeditem-content_type-object_id-0-id" id="id_generic_relations-taggeditem-content_type-object_id-0-id" /></p>""")
platypus = Animal.objects.create(
common_name="Platypus", latin_name="Ornithorhynchus anatinus"
)
platypus.tags.create(tag="shiny")
GenericFormSet = generic_inlineformset_factory(TaggedItem, extra=1)
formset = GenericFormSet(instance=platypus)
tagged_item_id = TaggedItem.objects.get(
tag='shiny', object_id=platypus.id
).id
self.assertHTMLEqual(''.join(form.as_p() for form in formset.forms), """<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-tag">Tag:</label> <input id="id_generic_relations-taggeditem-content_type-object_id-0-tag" type="text" name="generic_relations-taggeditem-content_type-object_id-0-tag" value="shiny" maxlength="50" /></p>
<p><label for="id_generic_relations-taggeditem-content_type-object_id-0-DELETE">Delete:</label> <input type="checkbox" name="generic_relations-taggeditem-content_type-object_id-0-DELETE" id="id_generic_relations-taggeditem-content_type-object_id-0-DELETE" /><input type="hidden" name="generic_relations-taggeditem-content_type-object_id-0-id" value="%s" id="id_generic_relations-taggeditem-content_type-object_id-0-id" /></p><p><label for="id_generic_relations-taggeditem-content_type-object_id-1-tag">Tag:</label> <input id="id_generic_relations-taggeditem-content_type-object_id-1-tag" type="text" name="generic_relations-taggeditem-content_type-object_id-1-tag" maxlength="50" /></p>
<p><label for="id_generic_relations-taggeditem-content_type-object_id-1-DELETE">Delete:</label> <input type="checkbox" name="generic_relations-taggeditem-content_type-object_id-1-DELETE" id="id_generic_relations-taggeditem-content_type-object_id-1-DELETE" /><input type="hidden" name="generic_relations-taggeditem-content_type-object_id-1-id" id="id_generic_relations-taggeditem-content_type-object_id-1-id" /></p>""" % tagged_item_id)
lion = Animal.objects.create(common_name="Lion", latin_name="Panthera leo")
formset = GenericFormSet(instance=lion, prefix='x')
self.assertHTMLEqual(''.join(form.as_p() for form in formset.forms), """<p><label for="id_x-0-tag">Tag:</label> <input id="id_x-0-tag" type="text" name="x-0-tag" maxlength="50" /></p>
<p><label for="id_x-0-DELETE">Delete:</label> <input type="checkbox" name="x-0-DELETE" id="id_x-0-DELETE" /><input type="hidden" name="x-0-id" id="id_x-0-id" /></p>""")
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):
"""
Test that 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.filter(tags__tag="countertop").count(), 1)
def test_generic_inline_formsets_initial(self):
"""
Test for #17927 Initial values support for BaseGenericInlineFormSet.
"""
quartz = Mineral.objects.create(name="Quartz", hardness=7)
GenericFormSet = generic_inlineformset_factory(TaggedItem, extra=1)
ctype = ContentType.objects.get_for_model(quartz)
initial_data = [{
'tag': 'lizard',
'content_type': ctype.pk,
'object_id': quartz.pk,
}]
formset = GenericFormSet(initial=initial_data)
self.assertEqual(formset.forms[0].initial, initial_data[0])
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='')
class CustomWidget(forms.TextInput):
pass
class TaggedItemForm(forms.ModelForm):
class Meta:
model = TaggedItem
fields = '__all__'
widgets = {'tag': CustomWidget}
class GenericInlineFormsetTest(TestCase):
def test_generic_inlineformset_factory(self):
"""
Regression for #14572: Using base forms with widgets
defined in Meta should not raise errors.
"""
Formset = generic_inlineformset_factory(TaggedItem, TaggedItemForm)
form = Formset().forms[0]
self.assertIsInstance(form['tag'].field.widget, CustomWidget)
def test_save_new_uses_form_save(self):
"""
Regression for #16260: save_new should call form.save()
"""
class SaveTestForm(forms.ModelForm):
def save(self, *args, **kwargs):
self.instance.saved_by = "custom method"
return super(SaveTestForm, self).save(*args, **kwargs)
Formset = generic_inlineformset_factory(
ForProxyModelModel, fields='__all__', form=SaveTestForm)
instance = ProxyRelatedModel.objects.create()
data = {
'form-TOTAL_FORMS': '1',
'form-INITIAL_FORMS': '0',
'form-MAX_NUM_FORMS': '',
'form-0-title': 'foo',
}
formset = Formset(data, instance=instance, prefix='form')
self.assertTrue(formset.is_valid())
new_obj = formset.save()[0]
self.assertEqual(new_obj.saved_by, "custom method")
def test_save_new_for_proxy(self):
Formset = generic_inlineformset_factory(ForProxyModelModel,
fields='__all__', for_concrete_model=False)
instance = ProxyRelatedModel.objects.create()
data = {
'form-TOTAL_FORMS': '1',
'form-INITIAL_FORMS': '0',
'form-MAX_NUM_FORMS': '',
'form-0-title': 'foo',
}
formset = Formset(data, instance=instance, prefix='form')
self.assertTrue(formset.is_valid())
new_obj, = formset.save()
self.assertEqual(new_obj.obj, instance)
def test_save_new_for_concrete(self):
Formset = generic_inlineformset_factory(ForProxyModelModel,
fields='__all__', for_concrete_model=True)
instance = ProxyRelatedModel.objects.create()
data = {
'form-TOTAL_FORMS': '1',
'form-INITIAL_FORMS': '0',
'form-MAX_NUM_FORMS': '',
'form-0-title': 'foo',
}
formset = Formset(data, instance=instance, prefix='form')
self.assertTrue(formset.is_valid())
new_obj, = formset.save()
self.assertNotIsInstance(new_obj.obj, ProxyRelatedModel)
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 = [base]
newrel = ConcreteRelatedModel.objects.get(pk=newrel.pk)
self.assertEqual(base, newrel.bases.get())
class TestInitWithNoneArgument(TestCase):
def test_none_not_allowed(self):
# TaggedItem requires a content_type, initializing with None should
# raise a ValueError.
with six.assertRaisesRegex(self, ValueError,
'Cannot assign None: "TaggedItem.content_type" does not allow null values'):
TaggedItem(content_object=None)
def test_none_allowed(self):
# AllowsNullGFK doesn't require a content_type, so None argument should
# also be allowed.
AllowsNullGFK(content_object=None)