importlib PathFinder monkeypatch for Python issue 115911 (getcwd() EACCESS)

issue115911_mp.py

# Monkeypatch that replaces the importlib PathFinder in sys.meta_path
# with one that handles EACCES returned by libc getcwd() on macOS.
# Workaround for https://github.com/python/cpython/issues/115911

import errno
import sys
try:
    import _frozen_importlib_external
except ImportError:
    pass
else:
    class MonkeyPatchedPathFinder(_frozen_importlib_external.PathFinder):
        @classmethod
        def _path_importer_cache(cls, path):
            if path == '':
                try:
                    path = _frozen_importlib_external._os.getcwd()
                except OSError as exc:
                    if exc.errno in (errno.EACCES, errno.ENOENT):
                        return None
            return _frozen_importlib_external.PathFinder._path_importer_cache(path)

    for i, mpf in enumerate(sys.meta_path):
        if mpf is _frozen_importlib_external.PathFinder:
            sys.meta_path[i] = MonkeyPatchedPathFinder
    del i, mpf

Caveat: this only works for Python < 3.12. At time of writing Python 3.13 suffers the PermissionError before any user code is executed.