Refs #31180 -- Removed default_app_config application configuration variable per deprecation timeline.

django/apps/config.py

@@ -1,10 +1,8 @@
 import inspect
 import os
-import warnings
 from importlib import import_module
 
 from django.core.exceptions import ImproperlyConfigured
-from django.utils.deprecation import RemovedInDjango41Warning
 from django.utils.functional import cached_property
 from django.utils.module_loading import import_string, module_has_submodule
 
@@ -102,7 +100,6 @@ class AppConfig:
         """
         # create() eventually returns app_config_class(app_name, app_module).
         app_config_class = None
-        app_config_name = None
         app_name = None
         app_module = None
 
@@ -134,7 +131,6 @@ class AppConfig:
                 ]
                 if len(app_configs) == 1:
                     app_config_class = app_configs[0][1]
-                    app_config_name = '%s.%s' % (mod_path, app_configs[0][0])
                 else:
                     # Check if there's exactly one AppConfig subclass,
                     # among those that explicitly define default = True.
@@ -151,43 +147,11 @@ class AppConfig:
                         )
                     elif len(app_configs) == 1:
                         app_config_class = app_configs[0][1]
-                        app_config_name = '%s.%s' % (mod_path, app_configs[0][0])
 
-            # If app_module specifies a default_app_config, follow the link.
+            # Use the default app config class if we didn't find anything.
-            # default_app_config is deprecated, but still takes over the
+            if app_config_class is None:
-            # automatic detection for backwards compatibility during the
+                app_config_class = cls
-            # deprecation period.
+                app_name = entry
-            try:
-                new_entry = app_module.default_app_config
-            except AttributeError:
-                # Use the default app config class if we didn't find anything.
-                if app_config_class is None:
-                    app_config_class = cls
-                    app_name = entry
-            else:
-                message = (
-                    '%r defines default_app_config = %r. ' % (entry, new_entry)
-                )
-                if new_entry == app_config_name:
-                    message += (
-                        'Django now detects this configuration automatically. '
-                        'You can remove default_app_config.'
-                    )
-                else:
-                    message += (
-                        "However, Django's automatic detection %s. You should "
-                        "move the default config class to the apps submodule "
-                        "of your application and, if this module defines "
-                        "several config classes, mark the default one with "
-                        "default = True." % (
-                            "picked another configuration, %r" % app_config_name
-                            if app_config_name
-                            else "did not find this configuration"
-                        )
-                    )
-                warnings.warn(message, RemovedInDjango41Warning, stacklevel=2)
-                entry = new_entry
-                app_config_class = None
 
         # If import_string succeeds, entry is an app config class.
         if app_config_class is None:

docs/releases/4.1.txt

@@ -255,3 +255,5 @@ to remove usage of these features.
 
 * The ``whitelist`` argument and ``domain_whitelist`` attribute of
   ``django.core.validators.EmailValidator`` are removed.
+
+* The ``default_app_config`` application configuration variable is removed.

tests/apps/explicit_default_config_app/__init__.py

@@ -1 +0,0 @@
-default_app_config = 'apps.explicit_default_config_app.apps.ExplicitDefaultConfig'

tests/apps/explicit_default_config_app/apps.py

@@ -1,5 +0,0 @@
-from django.apps import AppConfig
-
-
-class ExplicitDefaultConfig(AppConfig):
-    name = 'apps.explicit_default_config_app'

tests/apps/explicit_default_config_empty_apps/__init__.py

@@ -1,7 +0,0 @@
-from django.apps import AppConfig
-
-default_app_config = 'apps.explicit_default_config_empty_apps.ExplicitDefaultConfigEmptyApps'
-
-
-class ExplicitDefaultConfigEmptyApps(AppConfig):
-    name = 'apps.explicit_default_config_empty_apps'

tests/apps/explicit_default_config_mismatch_app/__init__.py

@@ -1 +0,0 @@
-default_app_config = 'apps.explicit_default_config_mismatch_app.not_apps.ExplicitDefaultConfigMismatch'

tests/apps/explicit_default_config_mismatch_app/apps.py

@@ -1,5 +0,0 @@
-from django.apps import AppConfig
-
-
-class ImplicitDefaultConfigMismatch(AppConfig):
-    name = 'apps.explicit_default_config_mismatch_app'

tests/apps/explicit_default_config_mismatch_app/not_apps.py

@@ -1,5 +0,0 @@
-from django.apps import AppConfig
-
-
-class ExplicitDefaultConfigMismatch(AppConfig):
-    name = 'apps.explicit_default_config_mismatch_app'

tests/apps/explicit_default_config_without_apps/__init__.py

@@ -1,7 +0,0 @@
-from django.apps import AppConfig
-
-default_app_config = 'apps.explicit_default_config_without_apps.ExplicitDefaultConfigWithoutApps'
-
-
-class ExplicitDefaultConfigWithoutApps(AppConfig):
-    name = 'apps.explicit_default_config_without_apps'

tests/apps/tests.py

@@ -5,18 +5,9 @@ from django.apps.registry import Apps
 from django.contrib.admin.models import LogEntry
 from django.core.exceptions import AppRegistryNotReady, ImproperlyConfigured
 from django.db import models
-from django.test import SimpleTestCase, ignore_warnings, override_settings
+from django.test import SimpleTestCase, override_settings
 from django.test.utils import extend_sys_path, isolate_apps
-from django.utils.deprecation import RemovedInDjango41Warning
 
-from .explicit_default_config_app.apps import ExplicitDefaultConfig
-from .explicit_default_config_empty_apps import ExplicitDefaultConfigEmptyApps
-from .explicit_default_config_mismatch_app.not_apps import (
-    ExplicitDefaultConfigMismatch,
-)
-from .explicit_default_config_without_apps import (
-    ExplicitDefaultConfigWithoutApps,
-)
 from .models import SoAlternative, TotallyNormal, new_apps
 from .one_config_app.apps import OneConfig
 from .two_configs_one_default_app.apps import TwoConfig
@@ -511,106 +502,3 @@ class NamespacePackageAppTests(SimpleTestCase):
             with self.settings(INSTALLED_APPS=['nsapp.apps.NSAppConfig']):
                 app_config = apps.get_app_config('nsapp')
                 self.assertEqual(app_config.path, self.app_path)
-
-
-class DeprecationTests(SimpleTestCase):
-    @ignore_warnings(category=RemovedInDjango41Warning)
-    def test_explicit_default_app_config(self):
-        with self.settings(INSTALLED_APPS=['apps.explicit_default_config_app']):
-            config = apps.get_app_config('explicit_default_config_app')
-        self.assertIsInstance(config, ExplicitDefaultConfig)
-
-    def test_explicit_default_app_config_warning(self):
-        """
-        Load an app that specifies a default AppConfig class matching the
-        autodetected one.
-        """
-        msg = (
-            "'apps.explicit_default_config_app' defines default_app_config = "
-            "'apps.explicit_default_config_app.apps.ExplicitDefaultConfig'. "
-            "Django now detects this configuration automatically. You can "
-            "remove default_app_config."
-        )
-        with self.assertRaisesMessage(RemovedInDjango41Warning, msg):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_app']):
-                pass
-        with ignore_warnings(category=RemovedInDjango41Warning):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_app']):
-                self.assertIsInstance(
-                    apps.get_app_config('explicit_default_config_app'),
-                    ExplicitDefaultConfig,
-                )
-
-    def test_explicit_default_app_config_mismatch(self):
-        """
-        Load an app that specifies a default AppConfig class not matching the
-        autodetected one.
-        """
-        msg = (
-            "'apps.explicit_default_config_mismatch_app' defines "
-            "default_app_config = 'apps.explicit_default_config_mismatch_app."
-            "not_apps.ExplicitDefaultConfigMismatch'. However, Django's "
-            "automatic detection picked another configuration, 'apps."
-            "explicit_default_config_mismatch_app.apps."
-            "ImplicitDefaultConfigMismatch'. You should move the default "
-            "config class to the apps submodule of your application and, if "
-            "this module defines several config classes, mark the default one "
-            "with default = True."
-        )
-        with self.assertRaisesMessage(RemovedInDjango41Warning, msg):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_mismatch_app']):
-                pass
-        with ignore_warnings(category=RemovedInDjango41Warning):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_mismatch_app']):
-                self.assertIsInstance(
-                    apps.get_app_config('explicit_default_config_mismatch_app'),
-                    ExplicitDefaultConfigMismatch,
-                )
-
-    def test_explicit_default_app_config_empty_apps(self):
-        """
-        Load an app that specifies a default AppConfig class in __init__ and
-        have an empty apps module.
-        """
-        msg = (
-            "'apps.explicit_default_config_empty_apps' defines "
-            "default_app_config = 'apps.explicit_default_config_empty_apps."
-            "ExplicitDefaultConfigEmptyApps'. However, Django's automatic "
-            "detection did not find this configuration. You should move the "
-            "default config class to the apps submodule of your application "
-            "and, if this module defines several config classes, mark the "
-            "default one with default = True."
-        )
-        with self.assertRaisesMessage(RemovedInDjango41Warning, msg):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_empty_apps']):
-                pass
-        with ignore_warnings(category=RemovedInDjango41Warning):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_empty_apps']):
-                self.assertIsInstance(
-                    apps.get_app_config('explicit_default_config_empty_apps'),
-                    ExplicitDefaultConfigEmptyApps,
-                )
-
-    def test_explicit_default_app_config_without_apps(self):
-        """
-        Load an app that specifies a default AppConfig class in __init__ and do
-        not have an apps module.
-        """
-        msg = (
-            "'apps.explicit_default_config_without_apps' defines "
-            "default_app_config = 'apps.explicit_default_config_without_apps."
-            "ExplicitDefaultConfigWithoutApps'. However, Django's automatic "
-            "detection did not find this configuration. You should move the "
-            "default config class to the apps submodule of your application "
-            "and, if this module defines several config classes, mark the "
-            "default one with default = True."
-        )
-        with self.assertRaisesMessage(RemovedInDjango41Warning, msg):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_without_apps']):
-                pass
-        with ignore_warnings(category=RemovedInDjango41Warning):
-            with self.settings(INSTALLED_APPS=['apps.explicit_default_config_without_apps']):
-                self.assertIsInstance(
-                    apps.get_app_config('explicit_default_config_without_apps'),
-                    ExplicitDefaultConfigWithoutApps,
-                )