Fixed #25535 -- Made ForeignObject checks less strict. (80dac8c3) · Commits · Dom Sekotill / django

django/db/models/fields/related.py

+19 −6

Original line number	Diff line number	Diff line
		@@ -464,22 +464,35 @@ class ForeignObject(RelatedField):
		if not self.foreign_related_fields:
		return []

		has_unique_field = any(rel_field.unique
		for rel_field in self.foreign_related_fields)
		if not has_unique_field and len(self.foreign_related_fields) > 1:
		unique_foreign_fields = {
		frozenset([f.name])
		for f in self.remote_field.model._meta.get_fields()
		if getattr(f, 'unique', False)
		}
		unique_foreign_fields.update({
		frozenset(ut)
		for ut in self.remote_field.model._meta.unique_together
		})
		foreign_fields = {f.name for f in self.foreign_related_fields}

		has_unique_constraint = any(u <= foreign_fields for u in unique_foreign_fields)

		if not has_unique_constraint and len(self.foreign_related_fields) > 1:
		field_combination = ', '.join("'%s'" % rel_field.name
		for rel_field in self.foreign_related_fields)
		model_name = self.remote_field.model.__name__
		return [
		checks.Error(
		"None of the fields %s on model '%s' have a unique=True constraint."
		"No subset of the fields %s on model '%s' is unique"
		% (field_combination, model_name),
		hint="Add a unique=True on any of the fields %s of '%s', or add them all or a "
		"subset to a unique_together constraint."
		% (field_combination, model_name),
		hint=None,
		obj=self,
		id='fields.E310',
		)
		]
		elif not has_unique_field:
		elif not has_unique_constraint:
		field_name = self.foreign_related_fields[0].name
		model_name = self.remote_field.model.__name__
		return [

tests/foreign_object/tests.py

+60 −0

Original line number	Diff line number	Diff line
		@@ -2,6 +2,8 @@ import datetime
		from operator import attrgetter

		from django.core.exceptions import FieldError
		from django.db import models
		from django.db.models.fields.related import ForeignObject
		from django.test import TestCase, skipUnlessDBFeature
		from django.utils import translation

		@@ -391,3 +393,61 @@ class MultiColumnFKTests(TestCase):
		""" See: https://code.djangoproject.com/ticket/21566 """
		objs = [Person(name="abcd_%s" % i, person_country=self.usa) for i in range(0, 5)]
		Person.objects.bulk_create(objs, 10)

		def test_check_composite_foreign_object(self):
		class Parent(models.Model):
		a = models.PositiveIntegerField()
		b = models.PositiveIntegerField()

		class Meta:
		unique_together = (
		('a', 'b'),
		)

		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)

		self.assertEqual(errors, [])

		def test_check_subset_composite_foreign_object(self):
		class Parent(models.Model):
		a = models.PositiveIntegerField()
		b = models.PositiveIntegerField()
		c = models.PositiveIntegerField()

		class Meta:
		unique_together = (
		('a', 'b'),
		)

		class Child(models.Model):
		a = models.PositiveIntegerField()
		b = models.PositiveIntegerField()
		c = models.PositiveIntegerField()
		d = models.CharField(max_length=255)

		parent = ForeignObject(
		Parent,
		on_delete=models.SET_NULL,
		from_fields=('a', 'b', 'c'),
		to_fields=('a', 'b', 'c'),
		related_name='children',
		)

		field = Child._meta.get_field('parent')
		errors = field.check(from_model=Child)

		self.assertEqual(errors, [])

tests/invalid_models_tests/test_relative_fields.py

+80 −3

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@ 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 skipIfDBFeature
		from django.test.utils import override_settings
		@@ -507,9 +508,9 @@ class RelativeFieldTests(IsolatedModelsTestCase):
		errors = field.check()
		expected = [
		Error(
		"None of the fields 'country_id', 'city_id' on model 'Person' "
		"have a unique=True constraint.",
		hint=None,
		"No subset of the fields 'country_id', 'city_id' on model 'Person' is unique",
		hint="Add a unique=True on any of the fields 'country_id', 'city_id' of 'Person', "
		"or add them all or a subset to a unique_together constraint.",
		obj=field,
		id='fields.E310',
		)
		@@ -1395,3 +1396,79 @@ class M2mThroughFieldsTests(IsolatedModelsTestCase):
		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 a unique=True on any of the fields 'a', 'b' of 'Parent', or add them "
		"all or a subset to a unique_together constraint.",
		obj=field,
		id='fields.E310',
		),
		]
		self.assertEqual(expected, errors)

		def test_insersection_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 a unique=True on any of the fields 'a', 'b', 'd' of 'Parent', or add "
		"them all or a subset to a unique_together constraint.",
		obj=field,
		id='fields.E310',
		),
		]
		self.assertEqual(expected, errors)