Fixed #25746 -- Isolated inlined test models registration.

Thanks to Tim for the review.

7 files changed, 79 insertions, 93 deletions

diff --git a/tests/invalid_models_tests/base.py b/tests/invalid_models_tests/base.py
deleted file mode 100644
index 9459b313d6..0000000000
--- a/tests/invalid_models_tests/base.py
+++ /dev/null
@@ -1,18 +0,0 @@
-# -*- encoding: utf-8 -*-
-from __future__ import unicode_literals
-
-from django.apps import apps
-from django.test import SimpleTestCase
-
-
-class IsolatedModelsTestCase(SimpleTestCase):
-
-    def setUp(self):
-        # The unmanaged models need to be removed after the test in order to
-        # prevent bad interactions with the flush operation in other tests.
-        self._old_models = apps.app_configs['invalid_models_tests'].models.copy()
-
-    def tearDown(self):
-        apps.app_configs['invalid_models_tests'].models = self._old_models
-        apps.all_models['invalid_models_tests'] = self._old_models
-        apps.clear_cache()
diff --git a/tests/invalid_models_tests/test_backend_specific.py b/tests/invalid_models_tests/test_backend_specific.py
index 5be1d6f691..fd73853a03 100644
--- a/tests/invalid_models_tests/test_backend_specific.py
+++ b/tests/invalid_models_tests/test_backend_specific.py
@@ -3,9 +3,8 @@ from __future__ import unicode_literals
 
 from django.core.checks import Error
 from django.db import connections, models
-from django.test import mock
-
-from .base import IsolatedModelsTestCase
+from django.test import SimpleTestCase, mock
+from django.test.utils import isolate_apps
 
 
 def dummy_allow_migrate(db, app_label, **hints):
@@ -14,7 +13,8 @@ def dummy_allow_migrate(db, app_label, **hints):
     return db == 'default'
 
 
-class BackendSpecificChecksTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class BackendSpecificChecksTests(SimpleTestCase):
 
     @mock.patch('django.db.models.fields.router.allow_migrate', new=dummy_allow_migrate)
     def test_check_field(self):
diff --git a/tests/invalid_models_tests/test_custom_fields.py b/tests/invalid_models_tests/test_custom_fields.py
index 03e65b599b..4c379e70f5 100644
--- a/tests/invalid_models_tests/test_custom_fields.py
+++ b/tests/invalid_models_tests/test_custom_fields.py
@@ -1,9 +1,10 @@
 from django.db import models
+from django.test import SimpleTestCase
+from django.test.utils import isolate_apps
 
-from .base import IsolatedModelsTestCase
 
-
-class CustomFieldTest(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class CustomFieldTest(SimpleTestCase):
 
     def test_none_column(self):
         class NoColumnField(models.AutoField):
diff --git a/tests/invalid_models_tests/test_deprecated_fields.py b/tests/invalid_models_tests/test_deprecated_fields.py
index fa646515b3..7826596895 100644
--- a/tests/invalid_models_tests/test_deprecated_fields.py
+++ b/tests/invalid_models_tests/test_deprecated_fields.py
@@ -1,10 +1,11 @@
 from django.core import checks
 from django.db import models
+from django.test import SimpleTestCase
+from django.test.utils import isolate_apps
 
-from .base import IsolatedModelsTestCase
 
-
-class DeprecatedFieldsTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class DeprecatedFieldsTests(SimpleTestCase):
     def test_IPAddressField_deprecated(self):
         class IPAddressModel(models.Model):
             ip = models.IPAddressField()
diff --git a/tests/invalid_models_tests/test_models.py b/tests/invalid_models_tests/test_models.py
index 8e1f515b13..5764764341 100644
--- a/tests/invalid_models_tests/test_models.py
+++ b/tests/invalid_models_tests/test_models.py
@@ -6,9 +6,8 @@ import unittest
 from django.conf import settings
 from django.core.checks import Error
 from django.db import connections, models
-from django.test.utils import override_settings
-
-from .base import IsolatedModelsTestCase
+from django.test import SimpleTestCase
+from django.test.utils import isolate_apps, override_settings
 
 
 def get_max_column_name_length():
@@ -31,7 +30,8 @@ def get_max_column_name_length():
     return (allowed_len, db_alias)
 
 
-class IndexTogetherTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class IndexTogetherTests(SimpleTestCase):
 
     def test_non_iterable(self):
         class Model(models.Model):
@@ -146,7 +146,8 @@ class IndexTogetherTests(IsolatedModelsTestCase):
 
 
 # unique_together tests are very similar to index_together tests.
-class UniqueTogetherTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class UniqueTogetherTests(SimpleTestCase):
 
     def test_non_iterable(self):
         class Model(models.Model):
@@ -251,7 +252,8 @@ class UniqueTogetherTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class FieldNamesTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class FieldNamesTests(SimpleTestCase):
 
     def test_ending_with_underscore(self):
         class Model(models.Model):
@@ -434,7 +436,8 @@ class FieldNamesTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ShadowingFieldsTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class ShadowingFieldsTests(SimpleTestCase):
 
     def test_field_name_clash_with_child_accessor(self):
         class Parent(models.Model):
@@ -558,7 +561,8 @@ class ShadowingFieldsTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class OtherModelTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class OtherModelTests(SimpleTestCase):
 
     def test_unique_primary_key(self):
         invalid_id = models.IntegerField(primary_key=False)
diff --git a/tests/invalid_models_tests/test_ordinary_fields.py b/tests/invalid_models_tests/test_ordinary_fields.py
index 033970aae4..2a7e912f8c 100644
--- a/tests/invalid_models_tests/test_ordinary_fields.py
+++ b/tests/invalid_models_tests/test_ordinary_fields.py
@@ -5,14 +5,13 @@ import unittest
 
 from django.core.checks import Error, Warning as DjangoWarning
 from django.db import connection, models
-from django.test import TestCase
-from django.test.utils import override_settings
+from django.test import SimpleTestCase, TestCase
+from django.test.utils import isolate_apps, override_settings
 from django.utils.timezone import now
 
-from .base import IsolatedModelsTestCase
 
-
-class AutoFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class AutoFieldTests(SimpleTestCase):
 
     def test_valid_case(self):
         class Model(models.Model):
@@ -46,7 +45,8 @@ class AutoFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class BooleanFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class BooleanFieldTests(SimpleTestCase):
 
     def test_nullable_boolean_field(self):
         class Model(models.Model):
@@ -65,7 +65,8 @@ class BooleanFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class CharFieldTests(IsolatedModelsTestCase, TestCase):
+@isolate_apps('invalid_models_tests')
+class CharFieldTests(TestCase):
 
     def test_valid_field(self):
         class Model(models.Model):
@@ -216,7 +217,8 @@ class CharFieldTests(IsolatedModelsTestCase, TestCase):
         self.assertEqual(errors, expected)
 
 
-class DateFieldTests(IsolatedModelsTestCase, TestCase):
+@isolate_apps('invalid_models_tests')
+class DateFieldTests(TestCase):
 
     def test_auto_now_and_auto_now_add_raise_error(self):
         class Model(models.Model):
@@ -282,7 +284,8 @@ class DateFieldTests(IsolatedModelsTestCase, TestCase):
         self.test_fix_default_value()
 
 
-class DateTimeFieldTests(IsolatedModelsTestCase, TestCase):
+@isolate_apps('invalid_models_tests')
+class DateTimeFieldTests(TestCase):
 
     def test_fix_default_value(self):
         class Model(models.Model):
@@ -326,7 +329,8 @@ class DateTimeFieldTests(IsolatedModelsTestCase, TestCase):
         self.test_fix_default_value()
 
 
-class DecimalFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class DecimalFieldTests(SimpleTestCase):
 
     def test_required_attributes(self):
         class Model(models.Model):
@@ -420,7 +424,8 @@ class DecimalFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class FileFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class FileFieldTests(SimpleTestCase):
 
     def test_valid_case(self):
         class Model(models.Model):
@@ -464,7 +469,8 @@ class FileFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class FilePathFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class FilePathFieldTests(SimpleTestCase):
 
     def test_forbidden_files_and_folders(self):
         class Model(models.Model):
@@ -483,7 +489,8 @@ class FilePathFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class GenericIPAddressFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class GenericIPAddressFieldTests(SimpleTestCase):
 
     def test_non_nullable_blank(self):
         class Model(models.Model):
@@ -503,7 +510,8 @@ class GenericIPAddressFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ImageFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class ImageFieldTests(SimpleTestCase):
 
     def test_pillow_installed(self):
         try:
@@ -530,7 +538,8 @@ class ImageFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class IntegerFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class IntegerFieldTests(SimpleTestCase):
 
     def test_max_length_warning(self):
         class Model(models.Model):
@@ -549,7 +558,8 @@ class IntegerFieldTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class TimeFieldTests(IsolatedModelsTestCase, TestCase):
+@isolate_apps('invalid_models_tests')
+class TimeFieldTests(TestCase):
 
     def test_fix_default_value(self):
         class Model(models.Model):
diff --git a/tests/invalid_models_tests/test_relative_fields.py b/tests/invalid_models_tests/test_relative_fields.py
index f157f2beb8..c2895f681f 100644
--- a/tests/invalid_models_tests/test_relative_fields.py
+++ b/tests/invalid_models_tests/test_relative_fields.py
@@ -3,21 +3,19 @@ from __future__ import unicode_literals
 
 import warnings
 
-from django.apps.registry import Apps
 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
+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
 
-from .base import IsolatedModelsTestCase
 
-
-class RelativeFieldTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class RelativeFieldTests(SimpleTestCase):
 
     def test_valid_foreign_key_without_accessor(self):
         class Target(models.Model):
@@ -133,23 +131,18 @@ class RelativeFieldTests(IsolatedModelsTestCase):
         ]
         self.assertEqual(errors, expected)
 
-    def test_foreign_key_to_isolated_apps_model(self):
+    @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.
         """
-        test_apps = Apps(['invalid_models_tests'])
-
         class OtherModel(models.Model):
-            class Meta:
-                apps = test_apps
+            pass
 
         class Model(models.Model):
             foreign_key = models.ForeignKey('OtherModel', models.CASCADE)
 
-            class Meta:
-                apps = test_apps
-
         field = Model._meta.get_field('foreign_key')
         self.assertEqual(field.check(from_model=Model), [])
 
@@ -170,23 +163,18 @@ class RelativeFieldTests(IsolatedModelsTestCase):
         ]
         self.assertEqual(errors, expected)
 
-    def test_many_to_many_to_isolated_apps_model(self):
+    @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.
         """
-        test_apps = Apps(['invalid_models_tests'])
-
         class OtherModel(models.Model):
-            class Meta:
-                apps = test_apps
+            pass
 
         class Model(models.Model):
             m2m = models.ManyToManyField('OtherModel')
 
-            class Meta:
-                apps = test_apps
-
         field = Model._meta.get_field('m2m')
         self.assertEqual(field.check(from_model=Model), [])
 
@@ -329,30 +317,22 @@ class RelativeFieldTests(IsolatedModelsTestCase):
         ]
         self.assertEqual(errors, expected)
 
-    def test_many_to_many_through_isolated_apps_model(self):
+    @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.
         """
-        test_apps = Apps(['invalid_models_tests'])
-
         class GroupMember(models.Model):
             person = models.ForeignKey('Person', models.CASCADE)
             group = models.ForeignKey('Group', models.CASCADE)
 
-            class Meta:
-                apps = test_apps
-
         class Person(models.Model):
-            class Meta:
-                apps = test_apps
+            pass
 
         class Group(models.Model):
             members = models.ManyToManyField('Person', through='GroupMember')
 
-            class Meta:
-                apps = test_apps
-
         field = Group._meta.get_field('members')
         self.assertEqual(field.check(from_model=Group), [])
 
@@ -790,7 +770,8 @@ class RelativeFieldTests(IsolatedModelsTestCase):
             self.assertFalse(errors)
 
 
-class AccessorClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class AccessorClashTests(SimpleTestCase):
 
     def test_fk_to_integer(self):
         self._test_accessor_clash(
@@ -902,7 +883,8 @@ class AccessorClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ReverseQueryNameClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class ReverseQueryNameClashTests(SimpleTestCase):
 
     def test_fk_to_integer(self):
         self._test_reverse_query_name_clash(
@@ -958,7 +940,8 @@ class ReverseQueryNameClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ExplicitRelatedNameClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class ExplicitRelatedNameClashTests(SimpleTestCase):
 
     def test_fk_to_integer(self):
         self._test_explicit_related_name_clash(
@@ -1022,7 +1005,8 @@ class ExplicitRelatedNameClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ExplicitRelatedQueryNameClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class ExplicitRelatedQueryNameClashTests(SimpleTestCase):
 
     def test_fk_to_integer(self):
         self._test_explicit_related_query_name_clash(
@@ -1086,7 +1070,8 @@ class ExplicitRelatedQueryNameClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class SelfReferentialM2MClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class SelfReferentialM2MClashTests(SimpleTestCase):
 
     def test_clash_between_accessors(self):
         class Model(models.Model):
@@ -1181,7 +1166,8 @@ class SelfReferentialM2MClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, [])
 
 
-class SelfReferentialFKClashTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class SelfReferentialFKClashTests(SimpleTestCase):
 
     def test_accessor_clash(self):
         class Model(models.Model):
@@ -1244,7 +1230,8 @@ class SelfReferentialFKClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class ComplexClashTests(IsolatedModelsTestCase):
+@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.
@@ -1358,7 +1345,8 @@ class ComplexClashTests(IsolatedModelsTestCase):
         self.assertEqual(errors, expected)
 
 
-class M2mThroughFieldsTests(IsolatedModelsTestCase):
+@isolate_apps('invalid_models_tests')
+class M2mThroughFieldsTests(SimpleTestCase):
     def test_m2m_field_argument_validation(self):
         """
         Tests that ManyToManyField accepts the ``through_fields`` kwarg