Fixed #13190 -- Improved error handling for the case where no authentication backends are defined. Thanks to Joel3000 for the report, and Łukasz Rekucki for the final patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14793 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/auth/__init__.py

@@ -37,6 +37,8 @@ def get_backends():
     backends = []
     for backend_path in settings.AUTHENTICATION_BACKENDS:
         backends.append(load_backend(backend_path))
+    if not backends:
+        raise ImproperlyConfigured('No authentication backends have been defined. Does AUTHENTICATION_BACKENDS contain anything?')
     return backends
 
 def authenticate(**credentials):

django/contrib/auth/tests/__init__.py

@@ -1,4 +1,4 @@
-from django.contrib.auth.tests.auth_backends import BackendTest, RowlevelBackendTest, AnonymousUserBackendTest, NoAnonymousUserBackendTest
+from django.contrib.auth.tests.auth_backends import BackendTest, RowlevelBackendTest, AnonymousUserBackendTest, NoAnonymousUserBackendTest, NoBackendsTest
 from django.contrib.auth.tests.basic import BasicTestCase
 from django.contrib.auth.tests.decorators import LoginRequiredTestCase
 from django.contrib.auth.tests.forms import UserCreationFormTest, AuthenticationFormTest, SetPasswordFormTest, PasswordChangeFormTest, UserChangeFormTest, PasswordResetFormTest

django/contrib/auth/tests/auth_backends.py

@@ -3,6 +3,7 @@ import warnings
 from django.conf import settings
 from django.contrib.auth.models import User, Group, Permission, AnonymousUser
 from django.contrib.contenttypes.models import ContentType
+from django.core.exceptions import ImproperlyConfigured
 from django.test import TestCase
 
 
@@ -251,3 +252,18 @@ class NoAnonymousUserBackendTest(TestCase):
 
     def test_get_all_permissions(self):
         self.assertEqual(self.user1.get_all_permissions(TestObj()), set())
+
+class NoBackendsTest(TestCase):
+    """
+    Tests that an appropriate error is raised if no auth backends are provided.
+    """
+    def setUp(self):
+        self.old_AUTHENTICATION_BACKENDS = settings.AUTHENTICATION_BACKENDS
+        settings.AUTHENTICATION_BACKENDS = []
+        self.user = User.objects.create_user('test', 'test@example.com', 'test')
+
+    def tearDown(self):
+        settings.AUTHENTICATION_BACKENDS = self.old_AUTHENTICATION_BACKENDS
+
+    def test_raises_exception(self):
+        self.assertRaises(ImproperlyConfigured, self.user.has_perm, ('perm', TestObj(),))