1
0
mirror of https://github.com/django/django.git synced 2024-12-23 09:36:06 +00:00
django/tests/invalid_models_tests/test_relative_fields.py

1712 lines
63 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

# -*- encoding: utf-8 -*-
from __future__ import unicode_literals
import warnings
from django.core.checks import Error, Warning as DjangoWarning
from django.db import models
from django.db.models.fields.related import ForeignObject
from django.test import ignore_warnings
from django.test.testcases import SimpleTestCase, skipIfDBFeature
from django.test.utils import isolate_apps, override_settings
from django.utils import six
from django.utils.deprecation import RemovedInDjango20Warning
from django.utils.version import get_docs_version
@isolate_apps('invalid_models_tests')
class RelativeFieldTests(SimpleTestCase):
def test_valid_foreign_key_without_accessor(self):
class Target(models.Model):
# There would be a clash if Model.field installed an accessor.
model = models.IntegerField()
class Model(models.Model):
field = models.ForeignKey(Target, models.CASCADE, related_name='+')
field = Model._meta.get_field('field')
errors = field.check()
self.assertEqual(errors, [])
@ignore_warnings(category=RemovedInDjango20Warning)
def test_valid_foreign_key_without_on_delete(self):
class Target(models.Model):
model = models.IntegerField()
class Model(models.Model):
field = models.ForeignKey(Target, related_name='+')
def test_foreign_key_without_on_delete_warning(self):
with warnings.catch_warnings(record=True) as warns:
warnings.simplefilter('always') # prevent warnings from appearing as errors
class Target(models.Model):
model = models.IntegerField()
class Model(models.Model):
field = models.ForeignKey(Target, related_name='+')
self.assertEqual(len(warns), 1)
self.assertEqual(
str(warns[0].message),
'on_delete will be a required arg for ForeignKey in Django '
'2.0. Set it to models.CASCADE on models and in existing '
'migrations if you want to maintain the current default '
'behavior. See https://docs.djangoproject.com/en/%s/ref/models/fields/'
'#django.db.models.ForeignKey.on_delete' % get_docs_version(),
)
def test_foreign_key_to_field_as_arg(self):
with warnings.catch_warnings(record=True) as warns:
warnings.simplefilter('always') # prevent warnings from appearing as errors
class Target(models.Model):
model = models.IntegerField()
class Model(models.Model):
field = models.ForeignKey(Target, 'id')
self.assertEqual(len(warns), 1)
self.assertEqual(
str(warns[0].message),
"The signature for ForeignKey will change in Django 2.0. "
"Pass to_field='id' as a kwarg instead of as an arg."
)
def test_one_to_one_field_without_on_delete_warning(self):
with warnings.catch_warnings(record=True) as warns:
warnings.simplefilter('always') # prevent warnings from appearing as errors
class Target(models.Model):
model = models.IntegerField()
class Model(models.Model):
field = models.OneToOneField(Target, related_name='+')
self.assertEqual(len(warns), 1)
self.assertEqual(
str(warns[0].message),
'on_delete will be a required arg for OneToOneField in Django '
'2.0. Set it to models.CASCADE on models and in existing '
'migrations if you want to maintain the current default '
'behavior. See https://docs.djangoproject.com/en/%s/ref/models/fields/'
'#django.db.models.ForeignKey.on_delete' % get_docs_version(),
)
def test_one_to_one_field_to_field_as_arg(self):
with warnings.catch_warnings(record=True) as warns:
warnings.simplefilter('always') # prevent warnings from appearing as errors
class Target(models.Model):
model = models.IntegerField()
class Model(models.Model):
field = models.OneToOneField(Target, 'id')
self.assertEqual(len(warns), 1)
self.assertEqual(
str(warns[0].message),
"The signature for OneToOneField will change in Django 2.0. "
"Pass to_field='id' as a kwarg instead of as an arg."
)
def test_foreign_key_to_missing_model(self):
# Model names are resolved when a model is being created, so we cannot
# test relative fields in isolation and we need to attach them to a
# model.
class Model(models.Model):
foreign_key = models.ForeignKey('Rel1', models.CASCADE)
field = Model._meta.get_field('foreign_key')
errors = field.check()
expected = [
Error(
"Field defines a relation with model 'Rel1', "
"which is either not installed, or is abstract.",
obj=field,
id='fields.E300',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
def test_foreign_key_to_isolate_apps_model(self):
"""
#25723 - Referenced model registration lookup should be run against the
field's model registry.
"""
class OtherModel(models.Model):
pass
class Model(models.Model):
foreign_key = models.ForeignKey('OtherModel', models.CASCADE)
field = Model._meta.get_field('foreign_key')
self.assertEqual(field.check(from_model=Model), [])
def test_many_to_many_to_missing_model(self):
class Model(models.Model):
m2m = models.ManyToManyField("Rel2")
field = Model._meta.get_field('m2m')
errors = field.check(from_model=Model)
expected = [
Error(
"Field defines a relation with model 'Rel2', "
"which is either not installed, or is abstract.",
obj=field,
id='fields.E300',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
def test_many_to_many_to_isolate_apps_model(self):
"""
#25723 - Referenced model registration lookup should be run against the
field's model registry.
"""
class OtherModel(models.Model):
pass
class Model(models.Model):
m2m = models.ManyToManyField('OtherModel')
field = Model._meta.get_field('m2m')
self.assertEqual(field.check(from_model=Model), [])
def test_many_to_many_with_limit_choices_auto_created_no_warning(self):
class Model(models.Model):
name = models.CharField(max_length=20)
class ModelM2M(models.Model):
m2m = models.ManyToManyField(Model, limit_choices_to={'name': 'test_name'})
self.assertEqual(ModelM2M.check(), [])
def test_many_to_many_with_useless_options(self):
class Model(models.Model):
name = models.CharField(max_length=20)
class ModelM2M(models.Model):
m2m = models.ManyToManyField(
Model,
null=True,
validators=[''],
limit_choices_to={'name': 'test_name'},
through='ThroughModel',
through_fields=('modelm2m', 'model'),
)
class ThroughModel(models.Model):
model = models.ForeignKey('Model', models.CASCADE)
modelm2m = models.ForeignKey('ModelM2M', models.CASCADE)
errors = ModelM2M.check()
field = ModelM2M._meta.get_field('m2m')
expected = [
DjangoWarning(
'null has no effect on ManyToManyField.',
obj=field,
id='fields.W340',
),
DjangoWarning(
'ManyToManyField does not support validators.',
obj=field,
id='fields.W341',
),
DjangoWarning(
'limit_choices_to has no effect on ManyToManyField '
'with a through model.',
obj=field,
id='fields.W343',
),
]
self.assertEqual(errors, expected)
def test_ambiguous_relationship_model(self):
class Person(models.Model):
pass
class Group(models.Model):
field = models.ManyToManyField('Person', through="AmbiguousRelationship", related_name='tertiary')
class AmbiguousRelationship(models.Model):
# Too much foreign keys to Person.
first_person = models.ForeignKey(Person, models.CASCADE, related_name="first")
second_person = models.ForeignKey(Person, models.CASCADE, related_name="second")
second_model = models.ForeignKey(Group, models.CASCADE)
field = Group._meta.get_field('field')
errors = field.check(from_model=Group)
expected = [
Error(
"The model is used as an intermediate model by "
"'invalid_models_tests.Group.field', but it has more than one "
"foreign key to 'Person', which is ambiguous. You must specify "
"which foreign key Django should use via the through_fields "
"keyword argument.",
hint=(
'If you want to create a recursive relationship, use '
'ForeignKey("self", symmetrical=False, through="AmbiguousRelationship").'
),
obj=field,
id='fields.E335',
),
]
self.assertEqual(errors, expected)
def test_relationship_model_with_foreign_key_to_wrong_model(self):
class WrongModel(models.Model):
pass
class Person(models.Model):
pass
class Group(models.Model):
members = models.ManyToManyField('Person', through="InvalidRelationship")
class InvalidRelationship(models.Model):
person = models.ForeignKey(Person, models.CASCADE)
wrong_foreign_key = models.ForeignKey(WrongModel, models.CASCADE)
# The last foreign key should point to Group model.
field = Group._meta.get_field('members')
errors = field.check(from_model=Group)
expected = [
Error(
"The model is used as an intermediate model by "
"'invalid_models_tests.Group.members', but it does not "
"have a foreign key to 'Group' or 'Person'.",
obj=InvalidRelationship,
id='fields.E336',
),
]
self.assertEqual(errors, expected)
def test_relationship_model_missing_foreign_key(self):
class Person(models.Model):
pass
class Group(models.Model):
members = models.ManyToManyField('Person', through="InvalidRelationship")
class InvalidRelationship(models.Model):
group = models.ForeignKey(Group, models.CASCADE)
# No foreign key to Person
field = Group._meta.get_field('members')
errors = field.check(from_model=Group)
expected = [
Error(
"The model is used as an intermediate model by "
"'invalid_models_tests.Group.members', but it does not have "
"a foreign key to 'Group' or 'Person'.",
obj=InvalidRelationship,
id='fields.E336',
),
]
self.assertEqual(errors, expected)
def test_missing_relationship_model(self):
class Person(models.Model):
pass
class Group(models.Model):
members = models.ManyToManyField('Person', through="MissingM2MModel")
field = Group._meta.get_field('members')
errors = field.check(from_model=Group)
expected = [
Error(
"Field specifies a many-to-many relation through model "
"'MissingM2MModel', which has not been installed.",
obj=field,
id='fields.E331',
),
]
self.assertEqual(errors, expected)
def test_missing_relationship_model_on_model_check(self):
class Person(models.Model):
pass
class Group(models.Model):
members = models.ManyToManyField('Person', through='MissingM2MModel')
self.assertEqual(Group.check(), [
Error(
"Field specifies a many-to-many relation through model "
"'MissingM2MModel', which has not been installed.",
obj=Group._meta.get_field('members'),
id='fields.E331',
),
])
@isolate_apps('invalid_models_tests')
def test_many_to_many_through_isolate_apps_model(self):
"""
#25723 - Through model registration lookup should be run against the
field's model registry.
"""
class GroupMember(models.Model):
person = models.ForeignKey('Person', models.CASCADE)
group = models.ForeignKey('Group', models.CASCADE)
class Person(models.Model):
pass
class Group(models.Model):
members = models.ManyToManyField('Person', through='GroupMember')
field = Group._meta.get_field('members')
self.assertEqual(field.check(from_model=Group), [])
def test_symmetrical_self_referential_field(self):
class Person(models.Model):
# Implicit symmetrical=False.
friends = models.ManyToManyField('self', through="Relationship")
class Relationship(models.Model):
first = models.ForeignKey(Person, models.CASCADE, related_name="rel_from_set")
second = models.ForeignKey(Person, models.CASCADE, related_name="rel_to_set")
field = Person._meta.get_field('friends')
errors = field.check(from_model=Person)
expected = [
Error(
'Many-to-many fields with intermediate tables must not be symmetrical.',
obj=field,
id='fields.E332',
),
]
self.assertEqual(errors, expected)
def test_too_many_foreign_keys_in_self_referential_model(self):
class Person(models.Model):
friends = models.ManyToManyField('self', through="InvalidRelationship", symmetrical=False)
class InvalidRelationship(models.Model):
first = models.ForeignKey(Person, models.CASCADE, related_name="rel_from_set_2")
second = models.ForeignKey(Person, models.CASCADE, related_name="rel_to_set_2")
third = models.ForeignKey(Person, models.CASCADE, related_name="too_many_by_far")
field = Person._meta.get_field('friends')
errors = field.check(from_model=Person)
expected = [
Error(
"The model is used as an intermediate model by "
"'invalid_models_tests.Person.friends', but it has more than two "
"foreign keys to 'Person', which is ambiguous. You must specify "
"which two foreign keys Django should use via the through_fields "
"keyword argument.",
hint='Use through_fields to specify which two foreign keys Django should use.',
obj=InvalidRelationship,
id='fields.E333',
),
]
self.assertEqual(errors, expected)
def test_symmetric_self_reference_with_intermediate_table(self):
class Person(models.Model):
# Explicit symmetrical=True.
friends = models.ManyToManyField('self', through="Relationship", symmetrical=True)
class Relationship(models.Model):
first = models.ForeignKey(Person, models.CASCADE, related_name="rel_from_set")
second = models.ForeignKey(Person, models.CASCADE, related_name="rel_to_set")
field = Person._meta.get_field('friends')
errors = field.check(from_model=Person)
expected = [
Error(
'Many-to-many fields with intermediate tables must not be symmetrical.',
obj=field,
id='fields.E332',
),
]
self.assertEqual(errors, expected)
def test_symmetric_self_reference_with_intermediate_table_and_through_fields(self):
"""
Using through_fields in a m2m with an intermediate model shouldn't
mask its incompatibility with symmetry.
"""
class Person(models.Model):
# Explicit symmetrical=True.
friends = models.ManyToManyField(
'self',
symmetrical=True,
through="Relationship",
through_fields=('first', 'second'),
)
class Relationship(models.Model):
first = models.ForeignKey(Person, models.CASCADE, related_name="rel_from_set")
second = models.ForeignKey(Person, models.CASCADE, related_name="rel_to_set")
referee = models.ForeignKey(Person, models.CASCADE, related_name="referred")
field = Person._meta.get_field('friends')
errors = field.check(from_model=Person)
expected = [
Error(
'Many-to-many fields with intermediate tables must not be symmetrical.',
obj=field,
id='fields.E332',
),
]
self.assertEqual(errors, expected)
def test_foreign_key_to_abstract_model(self):
class AbstractModel(models.Model):
class Meta:
abstract = True
class Model(models.Model):
rel_string_foreign_key = models.ForeignKey('AbstractModel', models.CASCADE)
rel_class_foreign_key = models.ForeignKey(AbstractModel, models.CASCADE)
fields = [
Model._meta.get_field('rel_string_foreign_key'),
Model._meta.get_field('rel_class_foreign_key'),
]
expected_error = Error(
"Field defines a relation with model 'AbstractModel', "
"which is either not installed, or is abstract.",
id='fields.E300',
)
for field in fields:
expected_error.obj = field
errors = field.check()
self.assertEqual(errors, [expected_error])
def test_m2m_to_abstract_model(self):
class AbstractModel(models.Model):
class Meta:
abstract = True
class Model(models.Model):
rel_string_m2m = models.ManyToManyField('AbstractModel')
rel_class_m2m = models.ManyToManyField(AbstractModel)
fields = [
Model._meta.get_field('rel_string_m2m'),
Model._meta.get_field('rel_class_m2m'),
]
expected_error = Error(
"Field defines a relation with model 'AbstractModel', "
"which is either not installed, or is abstract.",
id='fields.E300',
)
for field in fields:
expected_error.obj = field
errors = field.check(from_model=Model)
self.assertEqual(errors, [expected_error])
def test_unique_m2m(self):
class Person(models.Model):
name = models.CharField(max_length=5)
class Group(models.Model):
members = models.ManyToManyField('Person', unique=True)
field = Group._meta.get_field('members')
errors = field.check(from_model=Group)
expected = [
Error(
'ManyToManyFields cannot be unique.',
obj=field,
id='fields.E330',
),
]
self.assertEqual(errors, expected)
def test_foreign_key_to_non_unique_field(self):
class Target(models.Model):
bad = models.IntegerField() # No unique=True
class Model(models.Model):
foreign_key = models.ForeignKey('Target', models.CASCADE, to_field='bad')
field = Model._meta.get_field('foreign_key')
errors = field.check()
expected = [
Error(
"'Target.bad' must set unique=True because it is referenced by a foreign key.",
obj=field,
id='fields.E311',
),
]
self.assertEqual(errors, expected)
def test_foreign_key_to_non_unique_field_under_explicit_model(self):
class Target(models.Model):
bad = models.IntegerField()
class Model(models.Model):
field = models.ForeignKey(Target, models.CASCADE, to_field='bad')
field = Model._meta.get_field('field')
errors = field.check()
expected = [
Error(
"'Target.bad' must set unique=True because it is referenced by a foreign key.",
obj=field,
id='fields.E311',
),
]
self.assertEqual(errors, expected)
def test_foreign_object_to_non_unique_fields(self):
class Person(models.Model):
# Note that both fields are not unique.
country_id = models.IntegerField()
city_id = models.IntegerField()
class MMembership(models.Model):
person_country_id = models.IntegerField()
person_city_id = models.IntegerField()
person = models.ForeignObject(
Person,
on_delete=models.CASCADE,
from_fields=['person_country_id', 'person_city_id'],
to_fields=['country_id', 'city_id'],
)
field = MMembership._meta.get_field('person')
errors = field.check()
expected = [
Error(
"No subset of the fields 'country_id', 'city_id' on model 'Person' is unique.",
hint=(
"Add unique=True on any of those fields or add at least "
"a subset of them to a unique_together constraint."
),
obj=field,
id='fields.E310',
)
]
self.assertEqual(errors, expected)
def test_on_delete_set_null_on_non_nullable_field(self):
class Person(models.Model):
pass
class Model(models.Model):
foreign_key = models.ForeignKey('Person', models.SET_NULL)
field = Model._meta.get_field('foreign_key')
errors = field.check()
expected = [
Error(
'Field specifies on_delete=SET_NULL, but cannot be null.',
hint='Set null=True argument on the field, or change the on_delete rule.',
obj=field,
id='fields.E320',
),
]
self.assertEqual(errors, expected)
def test_on_delete_set_default_without_default_value(self):
class Person(models.Model):
pass
class Model(models.Model):
foreign_key = models.ForeignKey('Person', models.SET_DEFAULT)
field = Model._meta.get_field('foreign_key')
errors = field.check()
expected = [
Error(
'Field specifies on_delete=SET_DEFAULT, but has no default value.',
hint='Set a default value, or change the on_delete rule.',
obj=field,
id='fields.E321',
),
]
self.assertEqual(errors, expected)
@skipIfDBFeature('interprets_empty_strings_as_nulls')
def test_nullable_primary_key(self):
class Model(models.Model):
field = models.IntegerField(primary_key=True, null=True)
field = Model._meta.get_field('field')
errors = field.check()
expected = [
Error(
'Primary keys must not have null=True.',
hint='Set null=False on the field, or remove primary_key=True argument.',
obj=field,
id='fields.E007',
),
]
self.assertEqual(errors, expected)
def test_not_swapped_model(self):
class SwappableModel(models.Model):
# A model that can be, but isn't swapped out. References to this
# model should *not* raise any validation error.
class Meta:
swappable = 'TEST_SWAPPABLE_MODEL'
class Model(models.Model):
explicit_fk = models.ForeignKey(
SwappableModel,
models.CASCADE,
related_name='explicit_fk',
)
implicit_fk = models.ForeignKey(
'invalid_models_tests.SwappableModel',
models.CASCADE,
related_name='implicit_fk',
)
explicit_m2m = models.ManyToManyField(SwappableModel, related_name='explicit_m2m')
implicit_m2m = models.ManyToManyField(
'invalid_models_tests.SwappableModel',
related_name='implicit_m2m',
)
explicit_fk = Model._meta.get_field('explicit_fk')
self.assertEqual(explicit_fk.check(), [])
implicit_fk = Model._meta.get_field('implicit_fk')
self.assertEqual(implicit_fk.check(), [])
explicit_m2m = Model._meta.get_field('explicit_m2m')
self.assertEqual(explicit_m2m.check(from_model=Model), [])
implicit_m2m = Model._meta.get_field('implicit_m2m')
self.assertEqual(implicit_m2m.check(from_model=Model), [])
@override_settings(TEST_SWAPPED_MODEL='invalid_models_tests.Replacement')
def test_referencing_to_swapped_model(self):
class Replacement(models.Model):
pass
class SwappedModel(models.Model):
class Meta:
swappable = 'TEST_SWAPPED_MODEL'
class Model(models.Model):
explicit_fk = models.ForeignKey(
SwappedModel,
models.CASCADE,
related_name='explicit_fk',
)
implicit_fk = models.ForeignKey(
'invalid_models_tests.SwappedModel',
models.CASCADE,
related_name='implicit_fk',
)
explicit_m2m = models.ManyToManyField(SwappedModel, related_name='explicit_m2m')
implicit_m2m = models.ManyToManyField(
'invalid_models_tests.SwappedModel',
related_name='implicit_m2m',
)
fields = [
Model._meta.get_field('explicit_fk'),
Model._meta.get_field('implicit_fk'),
Model._meta.get_field('explicit_m2m'),
Model._meta.get_field('implicit_m2m'),
]
expected_error = Error(
("Field defines a relation with the model "
"'invalid_models_tests.SwappedModel', which has been swapped out."),
hint="Update the relation to point at 'settings.TEST_SWAPPED_MODEL'.",
id='fields.E301',
)
for field in fields:
expected_error.obj = field
errors = field.check(from_model=Model)
self.assertEqual(errors, [expected_error])
def test_related_field_has_invalid_related_name(self):
digit = 0
illegal_non_alphanumeric = '!'
whitespace = '\t'
invalid_related_names = [
'%s_begins_with_digit' % digit,
'%s_begins_with_illegal_non_alphanumeric' % illegal_non_alphanumeric,
'%s_begins_with_whitespace' % whitespace,
'contains_%s_illegal_non_alphanumeric' % illegal_non_alphanumeric,
'contains_%s_whitespace' % whitespace,
'ends_with_with_illegal_non_alphanumeric_%s' % illegal_non_alphanumeric,
'ends_with_whitespace_%s' % whitespace,
'with', # a Python keyword
'related_name\n',
'',
]
# Python 2 crashes on non-ASCII strings.
if six.PY3:
invalid_related_names.append('')
class Parent(models.Model):
pass
for invalid_related_name in invalid_related_names:
Child = type(str('Child%s') % str(invalid_related_name), (models.Model,), {
'parent': models.ForeignKey('Parent', models.CASCADE, related_name=invalid_related_name),
'__module__': Parent.__module__,
})
field = Child._meta.get_field('parent')
errors = Child.check()
expected = [
Error(
"The name '%s' is invalid related_name for field Child%s.parent"
% (invalid_related_name, invalid_related_name),
hint="Related name must be a valid Python identifier or end with a '+'",
obj=field,
id='fields.E306',
),
]
self.assertEqual(errors, expected)
def test_related_field_has_valid_related_name(self):
lowercase = 'a'
uppercase = 'A'
digit = 0
related_names = [
'%s_starts_with_lowercase' % lowercase,
'%s_tarts_with_uppercase' % uppercase,
'_starts_with_underscore',
'contains_%s_digit' % digit,
'ends_with_plus+',
'_+',
'+',
]
# Python 2 crashes on non-ASCII strings.
if six.PY3:
related_names.extend(['', '試驗+'])
class Parent(models.Model):
pass
for related_name in related_names:
Child = type(str('Child_%s') % str(related_name), (models.Model,), {
'parent': models.ForeignKey('Parent', models.CASCADE, related_name=related_name),
'__module__': Parent.__module__,
})
errors = Child.check()
self.assertFalse(errors)
def test_to_fields_exist(self):
class Parent(models.Model):
pass
class Child(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
parent = ForeignObject(
Parent,
on_delete=models.SET_NULL,
from_fields=('a', 'b'),
to_fields=('a', 'b'),
)
field = Child._meta.get_field('parent')
expected = [
Error(
"The to_field 'a' doesn't exist on the related model 'invalid_models_tests.Parent'.",
obj=field,
id='fields.E312',
),
Error(
"The to_field 'b' doesn't exist on the related model 'invalid_models_tests.Parent'.",
obj=field,
id='fields.E312',
),
]
self.assertEqual(field.check(), expected)
def test_to_fields_not_checked_if_related_model_doesnt_exist(self):
class Child(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
parent = ForeignObject(
'invalid_models_tests.Parent',
on_delete=models.SET_NULL,
from_fields=('a', 'b'),
to_fields=('a', 'b'),
)
field = Child._meta.get_field('parent')
self.assertEqual(field.check(), [
Error(
"Field defines a relation with model 'invalid_models_tests.Parent', "
"which is either not installed, or is abstract.",
id='fields.E300',
obj=field,
),
])
def test_invalid_related_query_name(self):
class Target(models.Model):
pass
class Model(models.Model):
first = models.ForeignKey(Target, models.CASCADE, related_name='contains__double')
second = models.ForeignKey(Target, models.CASCADE, related_query_name='ends_underscore_')
self.assertEqual(Model.check(), [
Error(
"Reverse query name 'contains__double' must not contain '__'.",
hint=("Add or change a related_name or related_query_name "
"argument for this field."),
obj=Model._meta.get_field('first'),
id='fields.E309',
),
Error(
"Reverse query name 'ends_underscore_' must not end with an "
"underscore.",
hint=("Add or change a related_name or related_query_name "
"argument for this field."),
obj=Model._meta.get_field('second'),
id='fields.E308',
),
])
@isolate_apps('invalid_models_tests')
class AccessorClashTests(SimpleTestCase):
def test_fk_to_integer(self):
self._test_accessor_clash(
target=models.IntegerField(),
relative=models.ForeignKey('Target', models.CASCADE))
def test_fk_to_fk(self):
self._test_accessor_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ForeignKey('Target', models.CASCADE))
def test_fk_to_m2m(self):
self._test_accessor_clash(
target=models.ManyToManyField('Another'),
relative=models.ForeignKey('Target', models.CASCADE))
def test_m2m_to_integer(self):
self._test_accessor_clash(
target=models.IntegerField(),
relative=models.ManyToManyField('Target'))
def test_m2m_to_fk(self):
self._test_accessor_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ManyToManyField('Target'))
def test_m2m_to_m2m(self):
self._test_accessor_clash(
target=models.ManyToManyField('Another'),
relative=models.ManyToManyField('Target'))
def _test_accessor_clash(self, target, relative):
class Another(models.Model):
pass
class Target(models.Model):
model_set = target
class Model(models.Model):
rel = relative
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.rel' clashes with field name 'Target.model_set'.",
hint=("Rename field 'Target.model_set', or add/change "
"a related_name argument to the definition "
"for field 'Model.rel'."),
obj=Model._meta.get_field('rel'),
id='fields.E302',
),
]
self.assertEqual(errors, expected)
def test_clash_between_accessors(self):
class Target(models.Model):
pass
class Model(models.Model):
foreign = models.ForeignKey(Target, models.CASCADE)
m2m = models.ManyToManyField(Target)
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.foreign' clashes with reverse accessor for 'Model.m2m'.",
hint=(
"Add or change a related_name argument to the definition "
"for 'Model.foreign' or 'Model.m2m'."
),
obj=Model._meta.get_field('foreign'),
id='fields.E304',
),
Error(
"Reverse accessor for 'Model.m2m' clashes with reverse accessor for 'Model.foreign'.",
hint=(
"Add or change a related_name argument to the definition "
"for 'Model.m2m' or 'Model.foreign'."
),
obj=Model._meta.get_field('m2m'),
id='fields.E304',
),
]
self.assertEqual(errors, expected)
def test_m2m_to_m2m_with_inheritance(self):
""" Ref #22047. """
class Target(models.Model):
pass
class Model(models.Model):
children = models.ManyToManyField('Child', related_name="m2m_clash", related_query_name="no_clash")
class Parent(models.Model):
m2m_clash = models.ManyToManyField('Target')
class Child(Parent):
pass
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.children' clashes with field name 'Child.m2m_clash'.",
hint=(
"Rename field 'Child.m2m_clash', or add/change a related_name "
"argument to the definition for field 'Model.children'."
),
obj=Model._meta.get_field('children'),
id='fields.E302',
)
]
self.assertEqual(errors, expected)
def test_no_clash_for_hidden_related_name(self):
class Stub(models.Model):
pass
class ManyToManyRel(models.Model):
thing1 = models.ManyToManyField(Stub, related_name='+')
thing2 = models.ManyToManyField(Stub, related_name='+')
class FKRel(models.Model):
thing1 = models.ForeignKey(Stub, models.CASCADE, related_name='+')
thing2 = models.ForeignKey(Stub, models.CASCADE, related_name='+')
self.assertEqual(ManyToManyRel.check(), [])
self.assertEqual(FKRel.check(), [])
@isolate_apps('invalid_models_tests')
class ReverseQueryNameClashTests(SimpleTestCase):
def test_fk_to_integer(self):
self._test_reverse_query_name_clash(
target=models.IntegerField(),
relative=models.ForeignKey('Target', models.CASCADE))
def test_fk_to_fk(self):
self._test_reverse_query_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ForeignKey('Target', models.CASCADE))
def test_fk_to_m2m(self):
self._test_reverse_query_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ForeignKey('Target', models.CASCADE))
def test_m2m_to_integer(self):
self._test_reverse_query_name_clash(
target=models.IntegerField(),
relative=models.ManyToManyField('Target'))
def test_m2m_to_fk(self):
self._test_reverse_query_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ManyToManyField('Target'))
def test_m2m_to_m2m(self):
self._test_reverse_query_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ManyToManyField('Target'))
def _test_reverse_query_name_clash(self, target, relative):
class Another(models.Model):
pass
class Target(models.Model):
model = target
class Model(models.Model):
rel = relative
errors = Model.check()
expected = [
Error(
"Reverse query name for 'Model.rel' clashes with field name 'Target.model'.",
hint=(
"Rename field 'Target.model', or add/change a related_name "
"argument to the definition for field 'Model.rel'."
),
obj=Model._meta.get_field('rel'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
class ExplicitRelatedNameClashTests(SimpleTestCase):
def test_fk_to_integer(self):
self._test_explicit_related_name_clash(
target=models.IntegerField(),
relative=models.ForeignKey('Target', models.CASCADE, related_name='clash'))
def test_fk_to_fk(self):
self._test_explicit_related_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ForeignKey('Target', models.CASCADE, related_name='clash'))
def test_fk_to_m2m(self):
self._test_explicit_related_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ForeignKey('Target', models.CASCADE, related_name='clash'))
def test_m2m_to_integer(self):
self._test_explicit_related_name_clash(
target=models.IntegerField(),
relative=models.ManyToManyField('Target', related_name='clash'))
def test_m2m_to_fk(self):
self._test_explicit_related_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ManyToManyField('Target', related_name='clash'))
def test_m2m_to_m2m(self):
self._test_explicit_related_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ManyToManyField('Target', related_name='clash'))
def _test_explicit_related_name_clash(self, target, relative):
class Another(models.Model):
pass
class Target(models.Model):
clash = target
class Model(models.Model):
rel = relative
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.rel' clashes with field name 'Target.clash'.",
hint=(
"Rename field 'Target.clash', or add/change a related_name "
"argument to the definition for field 'Model.rel'."
),
obj=Model._meta.get_field('rel'),
id='fields.E302',
),
Error(
"Reverse query name for 'Model.rel' clashes with field name 'Target.clash'.",
hint=(
"Rename field 'Target.clash', or add/change a related_name "
"argument to the definition for field 'Model.rel'."
),
obj=Model._meta.get_field('rel'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
class ExplicitRelatedQueryNameClashTests(SimpleTestCase):
def test_fk_to_integer(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.IntegerField(),
relative=models.ForeignKey(
'Target',
models.CASCADE,
related_name=related_name,
related_query_name='clash',
)
)
def test_hidden_fk_to_integer(self, related_name=None):
self.test_fk_to_integer(related_name='+')
def test_fk_to_fk(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ForeignKey(
'Target',
models.CASCADE,
related_name=related_name,
related_query_name='clash',
)
)
def test_hidden_fk_to_fk(self):
self.test_fk_to_fk(related_name='+')
def test_fk_to_m2m(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ForeignKey(
'Target',
models.CASCADE,
related_name=related_name,
related_query_name='clash',
)
)
def test_hidden_fk_to_m2m(self):
self.test_fk_to_m2m(related_name='+')
def test_m2m_to_integer(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.IntegerField(),
relative=models.ManyToManyField('Target', related_name=related_name, related_query_name='clash'))
def test_hidden_m2m_to_integer(self):
self.test_m2m_to_integer(related_name='+')
def test_m2m_to_fk(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.ForeignKey('Another', models.CASCADE),
relative=models.ManyToManyField('Target', related_name=related_name, related_query_name='clash'))
def test_hidden_m2m_to_fk(self):
self.test_m2m_to_fk(related_name='+')
def test_m2m_to_m2m(self, related_name=None):
self._test_explicit_related_query_name_clash(
target=models.ManyToManyField('Another'),
relative=models.ManyToManyField(
'Target',
related_name=related_name,
related_query_name='clash',
)
)
def test_hidden_m2m_to_m2m(self):
self.test_m2m_to_m2m(related_name='+')
def _test_explicit_related_query_name_clash(self, target, relative):
class Another(models.Model):
pass
class Target(models.Model):
clash = target
class Model(models.Model):
rel = relative
errors = Model.check()
expected = [
Error(
"Reverse query name for 'Model.rel' clashes with field name 'Target.clash'.",
hint=(
"Rename field 'Target.clash', or add/change a related_name "
"argument to the definition for field 'Model.rel'."
),
obj=Model._meta.get_field('rel'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
class SelfReferentialM2MClashTests(SimpleTestCase):
def test_clash_between_accessors(self):
class Model(models.Model):
first_m2m = models.ManyToManyField('self', symmetrical=False)
second_m2m = models.ManyToManyField('self', symmetrical=False)
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.first_m2m' clashes with reverse accessor for 'Model.second_m2m'.",
hint=(
"Add or change a related_name argument to the definition "
"for 'Model.first_m2m' or 'Model.second_m2m'."
),
obj=Model._meta.get_field('first_m2m'),
id='fields.E304',
),
Error(
"Reverse accessor for 'Model.second_m2m' clashes with reverse accessor for 'Model.first_m2m'.",
hint=(
"Add or change a related_name argument to the definition "
"for 'Model.second_m2m' or 'Model.first_m2m'."
),
obj=Model._meta.get_field('second_m2m'),
id='fields.E304',
),
]
self.assertEqual(errors, expected)
def test_accessor_clash(self):
class Model(models.Model):
model_set = models.ManyToManyField("self", symmetrical=False)
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.model_set' clashes with field name 'Model.model_set'.",
hint=(
"Rename field 'Model.model_set', or add/change a related_name "
"argument to the definition for field 'Model.model_set'."
),
obj=Model._meta.get_field('model_set'),
id='fields.E302',
),
]
self.assertEqual(errors, expected)
def test_reverse_query_name_clash(self):
class Model(models.Model):
model = models.ManyToManyField("self", symmetrical=False)
errors = Model.check()
expected = [
Error(
"Reverse query name for 'Model.model' clashes with field name 'Model.model'.",
hint=(
"Rename field 'Model.model', or add/change a related_name "
"argument to the definition for field 'Model.model'."
),
obj=Model._meta.get_field('model'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
def test_clash_under_explicit_related_name(self):
class Model(models.Model):
clash = models.IntegerField()
m2m = models.ManyToManyField("self", symmetrical=False, related_name='clash')
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.m2m' clashes with field name 'Model.clash'.",
hint=(
"Rename field 'Model.clash', or add/change a related_name "
"argument to the definition for field 'Model.m2m'."
),
obj=Model._meta.get_field('m2m'),
id='fields.E302',
),
Error(
"Reverse query name for 'Model.m2m' clashes with field name 'Model.clash'.",
hint=(
"Rename field 'Model.clash', or add/change a related_name "
"argument to the definition for field 'Model.m2m'."
),
obj=Model._meta.get_field('m2m'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
def test_valid_model(self):
class Model(models.Model):
first = models.ManyToManyField("self", symmetrical=False, related_name='first_accessor')
second = models.ManyToManyField("self", symmetrical=False, related_name='second_accessor')
errors = Model.check()
self.assertEqual(errors, [])
@isolate_apps('invalid_models_tests')
class SelfReferentialFKClashTests(SimpleTestCase):
def test_accessor_clash(self):
class Model(models.Model):
model_set = models.ForeignKey("Model", models.CASCADE)
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.model_set' clashes with field name 'Model.model_set'.",
hint=(
"Rename field 'Model.model_set', or add/change "
"a related_name argument to the definition "
"for field 'Model.model_set'."
),
obj=Model._meta.get_field('model_set'),
id='fields.E302',
),
]
self.assertEqual(errors, expected)
def test_reverse_query_name_clash(self):
class Model(models.Model):
model = models.ForeignKey("Model", models.CASCADE)
errors = Model.check()
expected = [
Error(
"Reverse query name for 'Model.model' clashes with field name 'Model.model'.",
hint=(
"Rename field 'Model.model', or add/change a related_name "
"argument to the definition for field 'Model.model'."
),
obj=Model._meta.get_field('model'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
def test_clash_under_explicit_related_name(self):
class Model(models.Model):
clash = models.CharField(max_length=10)
foreign = models.ForeignKey("Model", models.CASCADE, related_name='clash')
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.foreign' clashes with field name 'Model.clash'.",
hint=(
"Rename field 'Model.clash', or add/change a related_name "
"argument to the definition for field 'Model.foreign'."
),
obj=Model._meta.get_field('foreign'),
id='fields.E302',
),
Error(
"Reverse query name for 'Model.foreign' clashes with field name 'Model.clash'.",
hint=(
"Rename field 'Model.clash', or add/change a related_name "
"argument to the definition for field 'Model.foreign'."
),
obj=Model._meta.get_field('foreign'),
id='fields.E303',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
class ComplexClashTests(SimpleTestCase):
# New tests should not be included here, because this is a single,
# self-contained sanity check, not a test of everything.
def test_complex_clash(self):
class Target(models.Model):
tgt_safe = models.CharField(max_length=10)
clash = models.CharField(max_length=10)
model = models.CharField(max_length=10)
clash1_set = models.CharField(max_length=10)
class Model(models.Model):
src_safe = models.CharField(max_length=10)
foreign_1 = models.ForeignKey(Target, models.CASCADE, related_name='id')
foreign_2 = models.ForeignKey(Target, models.CASCADE, related_name='src_safe')
m2m_1 = models.ManyToManyField(Target, related_name='id')
m2m_2 = models.ManyToManyField(Target, related_name='src_safe')
errors = Model.check()
expected = [
Error(
"Reverse accessor for 'Model.foreign_1' clashes with field name 'Target.id'.",
hint=("Rename field 'Target.id', or add/change a related_name "
"argument to the definition for field 'Model.foreign_1'."),
obj=Model._meta.get_field('foreign_1'),
id='fields.E302',
),
Error(
"Reverse query name for 'Model.foreign_1' clashes with field name 'Target.id'.",
hint=("Rename field 'Target.id', or add/change a related_name "
"argument to the definition for field 'Model.foreign_1'."),
obj=Model._meta.get_field('foreign_1'),
id='fields.E303',
),
Error(
"Reverse accessor for 'Model.foreign_1' clashes with reverse accessor for 'Model.m2m_1'.",
hint=("Add or change a related_name argument to "
"the definition for 'Model.foreign_1' or 'Model.m2m_1'."),
obj=Model._meta.get_field('foreign_1'),
id='fields.E304',
),
Error(
"Reverse query name for 'Model.foreign_1' clashes with reverse query name for 'Model.m2m_1'.",
hint=("Add or change a related_name argument to "
"the definition for 'Model.foreign_1' or 'Model.m2m_1'."),
obj=Model._meta.get_field('foreign_1'),
id='fields.E305',
),
Error(
"Reverse accessor for 'Model.foreign_2' clashes with reverse accessor for 'Model.m2m_2'.",
hint=("Add or change a related_name argument "
"to the definition for 'Model.foreign_2' or 'Model.m2m_2'."),
obj=Model._meta.get_field('foreign_2'),
id='fields.E304',
),
Error(
"Reverse query name for 'Model.foreign_2' clashes with reverse query name for 'Model.m2m_2'.",
hint=("Add or change a related_name argument to "
"the definition for 'Model.foreign_2' or 'Model.m2m_2'."),
obj=Model._meta.get_field('foreign_2'),
id='fields.E305',
),
Error(
"Reverse accessor for 'Model.m2m_1' clashes with field name 'Target.id'.",
hint=("Rename field 'Target.id', or add/change a related_name "
"argument to the definition for field 'Model.m2m_1'."),
obj=Model._meta.get_field('m2m_1'),
id='fields.E302',
),
Error(
"Reverse query name for 'Model.m2m_1' clashes with field name 'Target.id'.",
hint=("Rename field 'Target.id', or add/change a related_name "
"argument to the definition for field 'Model.m2m_1'."),
obj=Model._meta.get_field('m2m_1'),
id='fields.E303',
),
Error(
"Reverse accessor for 'Model.m2m_1' clashes with reverse accessor for 'Model.foreign_1'.",
hint=("Add or change a related_name argument to the definition "
"for 'Model.m2m_1' or 'Model.foreign_1'."),
obj=Model._meta.get_field('m2m_1'),
id='fields.E304',
),
Error(
"Reverse query name for 'Model.m2m_1' clashes with reverse query name for 'Model.foreign_1'.",
hint=("Add or change a related_name argument to "
"the definition for 'Model.m2m_1' or 'Model.foreign_1'."),
obj=Model._meta.get_field('m2m_1'),
id='fields.E305',
),
Error(
"Reverse accessor for 'Model.m2m_2' clashes with reverse accessor for 'Model.foreign_2'.",
hint=("Add or change a related_name argument to the definition "
"for 'Model.m2m_2' or 'Model.foreign_2'."),
obj=Model._meta.get_field('m2m_2'),
id='fields.E304',
),
Error(
"Reverse query name for 'Model.m2m_2' clashes with reverse query name for 'Model.foreign_2'.",
hint=("Add or change a related_name argument to the definition "
"for 'Model.m2m_2' or 'Model.foreign_2'."),
obj=Model._meta.get_field('m2m_2'),
id='fields.E305',
),
]
self.assertEqual(errors, expected)
@isolate_apps('invalid_models_tests')
class M2mThroughFieldsTests(SimpleTestCase):
def test_m2m_field_argument_validation(self):
"""
Tests that ManyToManyField accepts the ``through_fields`` kwarg
only if an intermediary table is specified.
"""
class Fan(models.Model):
pass
with self.assertRaisesMessage(ValueError, 'Cannot specify through_fields without a through model'):
models.ManyToManyField(Fan, through_fields=('f1', 'f2'))
def test_invalid_order(self):
"""
Tests that mixing up the order of link fields to ManyToManyField.through_fields
triggers validation errors.
"""
class Fan(models.Model):
pass
class Event(models.Model):
invitees = models.ManyToManyField(Fan, through='Invitation', through_fields=('invitee', 'event'))
class Invitation(models.Model):
event = models.ForeignKey(Event, models.CASCADE)
invitee = models.ForeignKey(Fan, models.CASCADE)
inviter = models.ForeignKey(Fan, models.CASCADE, related_name='+')
field = Event._meta.get_field('invitees')
errors = field.check(from_model=Event)
expected = [
Error(
"'Invitation.invitee' is not a foreign key to 'Event'.",
hint="Did you mean one of the following foreign keys to 'Event': event?",
obj=field,
id='fields.E339',
),
Error(
"'Invitation.event' is not a foreign key to 'Fan'.",
hint="Did you mean one of the following foreign keys to 'Fan': invitee, inviter?",
obj=field,
id='fields.E339',
),
]
self.assertEqual(expected, errors)
def test_invalid_field(self):
"""
Tests that providing invalid field names to ManyToManyField.through_fields
triggers validation errors.
"""
class Fan(models.Model):
pass
class Event(models.Model):
invitees = models.ManyToManyField(
Fan,
through='Invitation',
through_fields=('invalid_field_1', 'invalid_field_2'),
)
class Invitation(models.Model):
event = models.ForeignKey(Event, models.CASCADE)
invitee = models.ForeignKey(Fan, models.CASCADE)
inviter = models.ForeignKey(Fan, models.CASCADE, related_name='+')
field = Event._meta.get_field('invitees')
errors = field.check(from_model=Event)
expected = [
Error(
"The intermediary model 'invalid_models_tests.Invitation' has no field 'invalid_field_1'.",
hint="Did you mean one of the following foreign keys to 'Event': event?",
obj=field,
id='fields.E338',
),
Error(
"The intermediary model 'invalid_models_tests.Invitation' has no field 'invalid_field_2'.",
hint="Did you mean one of the following foreign keys to 'Fan': invitee, inviter?",
obj=field,
id='fields.E338',
),
]
self.assertEqual(expected, errors)
def test_explicit_field_names(self):
"""
Tests that if ``through_fields`` kwarg is given, it must specify both
link fields of the intermediary table.
"""
class Fan(models.Model):
pass
class Event(models.Model):
invitees = models.ManyToManyField(Fan, through='Invitation', through_fields=(None, 'invitee'))
class Invitation(models.Model):
event = models.ForeignKey(Event, models.CASCADE)
invitee = models.ForeignKey(Fan, models.CASCADE)
inviter = models.ForeignKey(Fan, models.CASCADE, related_name='+')
field = Event._meta.get_field('invitees')
errors = field.check(from_model=Event)
expected = [
Error(
"Field specifies 'through_fields' but does not provide the names "
"of the two link fields that should be used for the relation "
"through model 'invalid_models_tests.Invitation'.",
hint="Make sure you specify 'through_fields' as through_fields=('field1', 'field2')",
obj=field,
id='fields.E337')]
self.assertEqual(expected, errors)
def test_superset_foreign_object(self):
class Parent(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
c = models.PositiveIntegerField()
class Meta:
unique_together = (('a', 'b', 'c'),)
class Child(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
value = models.CharField(max_length=255)
parent = ForeignObject(
Parent,
on_delete=models.SET_NULL,
from_fields=('a', 'b'),
to_fields=('a', 'b'),
related_name='children',
)
field = Child._meta.get_field('parent')
errors = field.check(from_model=Child)
expected = [
Error(
"No subset of the fields 'a', 'b' on model 'Parent' is unique.",
hint=(
"Add unique=True on any of those fields or add at least "
"a subset of them to a unique_together constraint."
),
obj=field,
id='fields.E310',
),
]
self.assertEqual(expected, errors)
def test_intersection_foreign_object(self):
class Parent(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
c = models.PositiveIntegerField()
d = models.PositiveIntegerField()
class Meta:
unique_together = (('a', 'b', 'c'),)
class Child(models.Model):
a = models.PositiveIntegerField()
b = models.PositiveIntegerField()
d = models.PositiveIntegerField()
value = models.CharField(max_length=255)
parent = ForeignObject(
Parent,
on_delete=models.SET_NULL,
from_fields=('a', 'b', 'd'),
to_fields=('a', 'b', 'd'),
related_name='children',
)
field = Child._meta.get_field('parent')
errors = field.check(from_model=Child)
expected = [
Error(
"No subset of the fields 'a', 'b', 'd' on model 'Parent' is unique.",
hint=(
"Add unique=True on any of those fields or add at least "
"a subset of them to a unique_together constraint."
),
obj=field,
id='fields.E310',
),
]
self.assertEqual(expected, errors)