zipfile .suffix/.suffixes raises TypeError when zipfile has no filename

[graingert]

import io
import sys
import zipfile
import logging

logger = logging.getLogger(__name__)


def main():
    with zipfile.ZipFile(io.BytesIO(), "w") as zf:
        zfp = zipfile.Path(zf)
        try:
            print((zfp / "example").suffix)
        except TypeError:
            logger.exception("suffix failed")

        try:
            print((zfp / "example").suffixes)
        except TypeError:
            logger.exception("suffixes failed")

        try:
            print((zfp / ".gitignore")).stem
        except TypeError:
            logger.exception("stem failed")



if __name__ == "__main__":
    sys.exit(main())

output:

suffix failed
Traceback (most recent call last):
  File "/home/graingert/projects/demo_zipp_suffix.py", line 14, in main
    print((zfp / "example").suffix)
          ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/graingert/.virtualenvs/testing311/lib/python3.11/site-packages/zipp/__init__.py", line 307, in suffix
    return pathlib.Path(self.at).suffix or self.filename.suffix
                                           ^^^^^^^^^^^^^
  File "/home/graingert/.virtualenvs/testing311/lib/python3.11/site-packages/zipp/__init__.py", line 319, in filename
    return pathlib.Path(self.root.filename).joinpath(self.at)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 871, in __new__
    self = cls._from_parts(args)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 509, in _from_parts
    drv, root, parts = self._parse_args(args)
                       ^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 493, in _parse_args
    a = os.fspath(a)
        ^^^^^^^^^^^^
TypeError: expected str, bytes or os.PathLike object, not NoneType
suffixes failed
Traceback (most recent call last):
  File "/home/graingert/projects/demo_zipp_suffix.py", line 19, in main
    print((zfp / "example").suffixes)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/graingert/.virtualenvs/testing311/lib/python3.11/site-packages/zipp/__init__.py", line 311, in suffixes
    return pathlib.Path(self.at).suffixes or self.filename.suffixes
                                             ^^^^^^^^^^^^^
  File "/home/graingert/.virtualenvs/testing311/lib/python3.11/site-packages/zipp/__init__.py", line 319, in filename
    return pathlib.Path(self.root.filename).joinpath(self.at)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 871, in __new__
    self = cls._from_parts(args)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 509, in _from_parts
    drv, root, parts = self._parse_args(args)
                       ^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/pathlib.py", line 493, in _parse_args
    a = os.fspath(a)
        ^^^^^^^^^^^^
TypeError: expected str, bytes or os.PathLike object, not NoneType
stem failed
Traceback (most recent call last):
  File "/home/graingert/projects/demo_zipp_suffix.py", line 24, in main
    print((zfp / ".gitignore")).stem
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/graingert/.virtualenvs/testing311/lib/python3.11/site-packages/zipp/__init__.py", line 384, in __str__
    return posixpath.join(self.root.filename, self.at)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen posixpath>", line 76, in join
TypeError: expected str, bytes or os.PathLike object, not NoneType

[jaraco]

Thanks for the report. Will investigate.

[jaraco]

I'm not able to replicate the issue in tests. The tests are passing and they already exercised the first two concerns (filenames without an extension). And in 906d379, I added a test confirming that stem also works as expected with a filename starting with a dot.

[jaraco]

I found one error in the test above. The parentheses are misplaced for the .stem check and that's what's triggering the error. Rewriting the test allows it to pass:

        try:
            print((zfp / ".gitignore").stem)
        except TypeError:
            logger.exception("stem failed")

[jaraco]

Oh! The reason the other tests are failing is not because at has no suffix, but because root.filename has no suffix because root.filename is None.

[graingert]

@jaraco thanks for the fix!

[jaraco]

You bet. I'll be getting this and others rolled into CPython soon.

[graingert]

I'd also expect print((zfp / ".gitignore")) to work

[jaraco]

Yes. Good point. I think that came up in another thread. I'll address the __str__ concern in another bug (#107).