Fixed #30234 -- Disallowed non-upper settings in settings.configure().

tests/settings_tests/tests.py

@@ -1,7 +1,7 @@
 import os
 import sys
 import unittest
-from types import ModuleType
+from types import ModuleType, SimpleNamespace
 from unittest import mock
 
 from django.conf import ENVIRONMENT_VARIABLE, LazySettings, Settings, settings
@@ -318,6 +318,17 @@ class SettingsTests(SimpleTestCase):
         with self.assertRaisesMessage(RuntimeError, 'Settings already configured.'):
             settings.configure()
 
+    def test_nonupper_settings_prohibited_in_configure(self):
+        s = LazySettings()
+        with self.assertRaisesMessage(TypeError, "Setting 'foo' must be uppercase."):
+            s.configure(foo='bar')
+
+    def test_nonupper_settings_ignored_in_default_settings(self):
+        s = LazySettings()
+        s.configure(SimpleNamespace(foo='bar'))
+        with self.assertRaises(AttributeError):
+            getattr(s, 'foo')
+
     @requires_tz_support
     @mock.patch('django.conf.global_settings.TIME_ZONE', 'test')
     def test_incorrect_timezone(self):