Fixed #36837 -- Skipped backends not implementing (a)get_user() in (a)force_login().

Co-authored-by: Mykhailo Havelia <Arfey17.mg@gmail.com>

2 files changed, 26 insertions, 1 deletions

diff --git a/tests/test_client/auth_backends.py b/tests/test_client/auth_backends.py
index 97a2763aaa..a20b0be4de 100644
--- a/tests/test_client/auth_backends.py
+++ b/tests/test_client/auth_backends.py
@@ -1,4 +1,4 @@
-from django.contrib.auth.backends import ModelBackend
+from django.contrib.auth.backends import BaseBackend, ModelBackend
 
 
 class TestClientBackend(ModelBackend):
@@ -7,3 +7,9 @@ class TestClientBackend(ModelBackend):
 
 class BackendWithoutGetUserMethod:
     pass
+
+
+class PermissionOnlyBackend(BaseBackend):
+    """This class inherits from BaseBackend but does not implement get_user."""
+
+    pass
diff --git a/tests/test_client/tests.py b/tests/test_client/tests.py
index bc1472d88b..2ba9455d0c 100644
--- a/tests/test_client/tests.py
+++ b/tests/test_client/tests.py
@@ -794,6 +794,25 @@ class ClientTest(TestCase):
         self.client.force_login(self.u1)
         self.assertEqual(self.u1.backend, "django.contrib.auth.backends.ModelBackend")
 
+    @override_settings(
+        AUTHENTICATION_BACKENDS=[
+            "test_client.auth_backends.PermissionOnlyBackend",
+            "django.contrib.auth.backends.ModelBackend",
+        ]
+    )
+    def test_force_login_skips_noop_get_user_backend(self):
+        """force_login() skips auth backends without concrete get_user()."""
+        self.client.force_login(self.u1)
+        self.assertEqual(self.u1.backend, "django.contrib.auth.backends.ModelBackend")
+
+    @override_settings(
+        AUTHENTICATION_BACKENDS=[
+            "test_client.auth_backends.PermissionOnlyBackend",
+        ]
+    )
+    def test_force_login_all_backends_noop(self):
+        self.assertIsNone(self.client._get_backend())
+
     @override_settings(SESSION_ENGINE="django.contrib.sessions.backends.signed_cookies")
     def test_logout_cookie_sessions(self):
         self.test_logout()