Compile of Django admin.py with django-mass-edit package creates error when saving about cython HOT 6 CLOSED

from cython.

Have tested latest version - 3.0.7. Problem still occurs.

Not sure how to provide the traceback. The problem is reported in the GUI/Web page when I attempt to make changes to a field in my application.

I have attached a sample application to demonstrate the problem. Use username="sam" and password="Secret_123" to login to the admin screen ( /admin ). You can start the dev server using "python manage.py runserver 0:8000" from the pixel directory.

Further testing shows that the issue arrises when I create a custom save for my model. It does not occur if I don't have a custom save mode. The issue also only occurs only when I compile using Cython.
django_cython_error.tar.gz

The tar archive contains the Django project but you will likely need to install the requirements ( assume you will use a python venv).

The specific part of the code that causes the issue is in admin.py.

   # sample save_model - note indentation not shown

   def save_model(self, request, obj, form, change):
        obj.save()
        print(change)
        if change:
            print("change", change, obj.id)
            if not os.path.isdir(f'/tmp/{obj.id}'):
                os.mkdir(f'/tmp/{obj.id}')

Again - this code only creates the issue when the project is compiled with Cython. There is a setup.py file in the pixel directory that I used to compile the project with command "python setup.py build_ext --inplace"

Please let me know if there is anything else you need.

from cython.

Looking through Django's code a bit, there seems to be a metaclass involved for this class: MediaDefiningClass. It doesn't touch this specific method, but at least, it changes the way the class is instantiated. The method itself seems to be very ordinary and overriding it shouldn't harm. Also, the fact that it says "3 arguments given" instead of 5 seems odd. If anything goes wrong with a method, it's usually off by one due to self, not off by two. Difficult to say what's going wrong here.

from cython.

Not a Cython bug - this is a choice that django-mass-edit has made:

https://github.com/burke-software/django-mass-edit/blob/8f455b1ee05e9d5b7b3e4e5094928b4397fc405b/massadmin/massadmin.py#L125

        for (varname, var) in self.get_overrided_properties().items():
            if not varname.startswith('_') and not isinstance(var, types.FunctionType):
                self.__dict__[varname] = var

Cython functions don't pass the check isinstance(var, types.FunctionType), which checks for an regular Python function. Therefore your CustomerAdmin.save_model gets inappropriately copied over to overwrite MassAdmin.save_model and you end up in some sort of mess.

Cython functions are not regular Python functions by necessity. We made them look as much like Python functions as possible, but we can never pass an isinstance type check.

from cython.

If you want a reproducible example that doesn't use Cython then change your CustomerAdmin class to be:

class CustomerAdmin(...):  # put in the correct base class

    class Callable:
        def __call__(self, request, obj, form, change):
            ... # implementation of save_model goes here
    save_model = Callable()

This'll demonstrate the (roughly) same issue you see here.

from cython.

from cython.