def test_default_error_handler_calls_default_renderer(self): # Default error handler should call `render_errors` on the # registered renderer. service = Service("error service", "/error_service") renderer = mock.MagicMock() renderer.render_errors.return_value = "rendered_errors" request = mock.MagicMock() request.registry.queryUtility.return_value = renderer self.assertEqual(service.default_error_handler(request), "rendered_errors") request.registry.queryUtility.assert_called_with(IRendererFactory, name=service.renderer) renderer.render_errors.assert_called_with(request)