[Fixed]-User_passes_test: raise exception if user does not pass

In Django 1.9+, you can use the UserPassesTestMixin instead of a decorator, and set raise_exception to True.

Since you are using Django 1.4, which is insecure and obsolete, you won’t be able to do this. There isn’t an option to make user_passes_test raise PermissionDenied rather than redirect. You could either try to detect the redirect in your JavaScript, or look at the user_passes_test source code and implement something similar that returns the response you want.