django/tests/auth_tests/test_middleware.py

from django.contrib.auth.middleware import AuthenticationMiddleware
from django.contrib.auth.models import User
from django.http import HttpRequest
from django.test import TestCase


class TestAuthenticationMiddleware(TestCase):
    def setUp(self):
        self.user = User.objects.create_user('test_user', 'test@example.com', 'test_password')
        self.middleware = AuthenticationMiddleware()
        self.client.force_login(self.user)
        self.request = HttpRequest()
        self.request.session = self.client.session

    def test_no_password_change_doesnt_invalidate_session(self):
        self.request.session = self.client.session
        self.middleware.process_request(self.request)
        self.assertIsNotNone(self.request.user)
        self.assertFalse(self.request.user.is_anonymous())

    def test_changed_password_invalidates_session(self):
        # After password change, user should be anonymous
        self.user.set_password('new_password')
        self.user.save()
        self.middleware.process_request(self.request)
        self.assertIsNotNone(self.request.user)
        self.assertTrue(self.request.user.is_anonymous())
        # session should be flushed
        self.assertIsNone(self.request.session.session_key)