Add tests for dynamic settings middleware

devproject/settings.py

@@ -225,6 +225,7 @@ MIDDLEWARE = [
     'django.middleware.clickjacking.XFrameOptionsMiddleware',
 
     'misago.cache.middleware.cache_versions_middleware',
+    'misago.conf.middleware.dynamic_settings_middleware',
     'misago.users.middleware.UserMiddleware',
     'misago.acl.middleware.user_acl_middleware',
     'misago.core.middleware.ExceptionHandlerMiddleware',

misago/conf/middleware.py

@@ -0,0 +1,14 @@
+from django.utils.functional import SimpleLazyObject
+
+from .dynamicsettings import DynamicSettings
+
+
+def dynamic_settings_middleware(get_response):
+    """Sets request.settings attribute with DynamicSettings."""
+    def middleware(request):
+        def get_dynamic_settings():
+            return DynamicSettings(request.cache_versions)
+        request.settings = SimpleLazyObject(get_dynamic_settings)
+        return get_response(request)
+
+    return middleware

misago/conf/tests/test_dynamic_settings_middleware.py

@@ -0,0 +1,50 @@
+from unittest.mock import Mock, PropertyMock, patch
+
+from django.test import TestCase
+from django.utils.functional import SimpleLazyObject
+
+from misago.conf.dynamicsettings import DynamicSettings
+from misago.conf.middleware import dynamic_settings_middleware
+
+
+class MiddlewareTests(TestCase):
+    def test_middleware_sets_attr_on_request(self):
+        get_response = Mock()
+        request = Mock()
+        settings = PropertyMock()
+        type(request).settings = settings
+        middleware = dynamic_settings_middleware(get_response)
+        middleware(request)
+        settings.assert_called_once()
+
+    def test_attr_set_by_middleware_on_request_is_lazy_object(self):
+        get_response = Mock()
+        request = Mock()
+        settings = PropertyMock()
+        type(request).settings = settings
+        middleware = dynamic_settings_middleware(get_response)
+        middleware(request)
+        attr_value = settings.call_args[0][0]
+        assert isinstance(attr_value, SimpleLazyObject)
+
+    def test_middleware_calls_get_response(self):
+        get_response = Mock()
+        request = Mock()
+        middleware = dynamic_settings_middleware(get_response)
+        middleware(request)
+        get_response.assert_called_once()
+
+    def test_middleware_is_not_reading_db(self):
+        get_response = Mock()
+        request = Mock()
+        with self.assertNumQueries(0):
+            middleware = dynamic_settings_middleware(get_response)
+            middleware(request)
+
+    @patch('django.core.cache.cache.get')
+    def test_middleware_is_not_reading_cache(self, cache_get):
+        get_response = Mock()
+        request = Mock()
+        middleware = dynamic_settings_middleware(get_response)
+        middleware(request)
+        cache_get.assert_not_called()