Indeed, it looks like the bug is not introduced by this pull request.

With latest master, without this pull request:

a.pyx:

# cython: binding=True, language_level=3
import cython

cdef class A:
	def __call__(self, int a, float b):
		"""
		hello world
		"""
		print(1)

print(A.__call__.__doc__)

→

[tmp]$ CFLAGS=-DPy_LIMITED_API=0x03090000 cythonize -i a.pyx
Compiling /tmp/a.pyx because it changed.
[1/1] Cythonizing /tmp/a.pyx
[tmp]$ python -c "import a"
Call self as a function.
[tmp]$ rm -f a.c a.cpython-*
[tmp]$ cythonize -i a.pyx
Compiling /tmp/a.pyx because it changed.
[1/1] Cythonizing /tmp/a.pyx
[tmp]$ python -c "import a"

                hello world

What should I do (it shouldn't be in the scope of this pull request to also fix that issue?)

I think this is something where we can live with the Limited API not working quite right (especially since it seems to be pre-existing).

If you do

cdef extern from *:
    int CYTHON_COMPILING_IN_LIMITED_API

limited_api_on = True if CYTHON_COMPILING_IN_LIMITED_API else False

(or something similar) then you can see that's it's activated and disable the individual test.

Any idea why include.pyx → include "testinclude.pxi" works but
include "skip_limited_api_helper.pxi" is failing? Maybe because of the initial test or the underscore?

Not sure about the first but the test runner automatically copies all files called "currenttestname*.*" into the test execution directory (every test has its own directory) but not apparently unrelated files.

Maybe that's the cause.

    def related_files(self, test_directory, module_name):
        is_related = re.compile('%s_.*[.].*' % module_name).match
        return [filename for filename in list_unchanging_dir(test_directory)
                if is_related(filename)]

What is your recommendation here, copy paste the function to every file as before? (the alternative is to modify related_files to parse for include or some magic comment, I guess?)

… maybe the cause is I forget to git add it.

I guess I can run CI on my fork too, then no need for approval for debugging on my side. Let's see. https://github.com/user202729/cython/actions/runs/14247014745

Edit: yes looks like they all passes.

Thanks