UPD: more test.

dav_base/tests/test_apps.py

@@ -1,16 +1,13 @@
 from django.apps import apps
-from django.test import SimpleTestCase
+
+from .generic import AppSetting, AppsTestCase
 
 
-class AppsTestCase(SimpleTestCase):
-    def setUp(self):
-        app_config = apps.get_containing_app_config(__package__)
-        self.settings = app_config.settings
+class TestCase(AppsTestCase):
+    app_config = apps.get_app_config('dav_base')
 
-    def test_settings(self):
-        setting_names = ('email_sender',
-                         'email_base_url',
-                         'email_subject_prefix')
-
-        for s in setting_names:
-            self.assertTrue(hasattr(self.settings, s), 'Settings do not contain {}'.format(s))
+    settings = (
+        AppSetting('email_sender', basestring),
+        AppSetting('email_base_url', basestring),
+        AppSetting('email_subject_prefix', basestring),
+    )