Refs #24590 -- Ensured isolation between autodetector tests

Fixed a regression introduced in e1427cc609 when running tests in reverse order.

tests/field_deconstruction/tests.py

@@ -226,6 +226,7 @@ class FieldDeconstructionTests(SimpleTestCase):
             # there's no validation. We just want to check the setting stuff works.
             field = models.ForeignKey("auth.Permission", models.CASCADE)
             name, path, args, kwargs = field.deconstruct()
+
         self.assertEqual(path, "django.db.models.ForeignKey")
         self.assertEqual(args, [])
         self.assertEqual(kwargs, {"to": "auth.Permission", "on_delete": models.CASCADE})
@@ -305,6 +306,7 @@ class FieldDeconstructionTests(SimpleTestCase):
             # there's no validation. We just want to check the setting stuff works.
             field = models.ManyToManyField("auth.Permission")
             name, path, args, kwargs = field.deconstruct()
+
         self.assertEqual(path, "django.db.models.ManyToManyField")
         self.assertEqual(args, [])
         self.assertEqual(kwargs, {"to": "auth.Permission"})

tests/migrations/test_autodetector.py

@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 import re
 
+from django.apps import apps
 from django.conf import settings
 from django.contrib.auth.models import AbstractBaseUser
 from django.core.validators import RegexValidator, validate_slug
@@ -11,6 +12,7 @@ from django.db.migrations.loader import MigrationLoader
 from django.db.migrations.questioner import MigrationQuestioner
 from django.db.migrations.state import ModelState, ProjectState
 from django.test import TestCase, mock, override_settings
+from django.test.utils import isolate_lru_cache
 
 from .models import FoodManager, FoodQuerySet
 
@@ -1310,10 +1312,12 @@ class AutodetectorTests(TestCase):
 
     @override_settings(AUTH_USER_MODEL="thirdapp.CustomUser")
     def test_swappable(self):
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             before = self.make_project_state([self.custom_user])
             after = self.make_project_state([self.custom_user, self.author_with_custom_user])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'testapp', 1)
         self.assertOperationTypes(changes, 'testapp', 0, ["CreateModel"])
@@ -1321,11 +1325,13 @@ class AutodetectorTests(TestCase):
         self.assertMigrationDependencies(changes, 'testapp', 0, [("__setting__", "AUTH_USER_MODEL")])
 
     def test_swappable_changed(self):
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             before = self.make_project_state([self.custom_user, self.author_with_user])
             with override_settings(AUTH_USER_MODEL="thirdapp.CustomUser"):
                 after = self.make_project_state([self.custom_user, self.author_with_custom_user])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'testapp', 1)
         self.assertOperationTypes(changes, 'testapp', 0, ["AlterField"])
@@ -1815,11 +1821,13 @@ class AutodetectorTests(TestCase):
     @override_settings(AUTH_USER_MODEL="thirdapp.CustomUser")
     def test_swappable_first_setting(self):
         """Tests that swappable models get their CreateModel first."""
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             # Make state
             before = self.make_project_state([])
             after = self.make_project_state([self.custom_user_no_inherit, self.aardvark])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'thirdapp', 1)
         self.assertOperationTypes(changes, 'thirdapp', 0, ["CreateModel", "CreateModel"])
@@ -1999,6 +2007,7 @@ class AutodetectorTests(TestCase):
         #23322 - Tests that the dependency resolver knows to explicitly resolve
         swappable models.
         """
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             tenant = ModelState("a", "Tenant", [
                 ("id", models.AutoField(primary_key=True)),
                 ("primary_address", models.ForeignKey("b.Address", models.CASCADE))],
@@ -2013,6 +2022,7 @@ class AutodetectorTests(TestCase):
             after = self.make_project_state([address, tenant])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'a', 2)
         self.assertOperationTypes(changes, 'a', 0, ["CreateModel"])
@@ -2031,6 +2041,7 @@ class AutodetectorTests(TestCase):
         swappable models but with the swappable not being the first migrated
         model.
         """
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             address = ModelState("a", "Address", [
                 ("id", models.AutoField(primary_key=True)),
                 ("tenant", models.ForeignKey(settings.AUTH_USER_MODEL, models.CASCADE)),
@@ -2045,6 +2056,7 @@ class AutodetectorTests(TestCase):
             after = self.make_project_state([address, tenant])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'a', 2)
         self.assertOperationTypes(changes, 'a', 0, ["CreateModel"])
@@ -2062,6 +2074,7 @@ class AutodetectorTests(TestCase):
         #23322 - Tests that the dependency resolver knows to explicitly resolve
         swappable models.
         """
+        with isolate_lru_cache(apps.get_swappable_settings_name):
             person = ModelState("a", "Person", [
                 ("id", models.AutoField(primary_key=True)),
                 ("parent1", models.ForeignKey(settings.AUTH_USER_MODEL, models.CASCADE, related_name='children'))
@@ -2071,6 +2084,7 @@ class AutodetectorTests(TestCase):
             after = self.make_project_state([person])
             autodetector = MigrationAutodetector(before, after)
             changes = autodetector._detect_changes()
+
         # Right number/type of migrations?
         self.assertNumberMigrations(changes, 'a', 1)
         self.assertOperationTypes(changes, 'a', 0, ["CreateModel"])