tarfile.TarFile.next() adds an unnecessary traceback frame when reraising exceptions

[lpyu001]

description:

https://gist.github.com/devdanzin/f8af359770ff200eac8474de5644be82

tarfile.TarFile.next() currently reraises non-zlib exceptions with raise e
inside its generic exception handler:

except Exception as e:
    try:
        import zlib
        if isinstance(e, zlib.error):
            raise ReadError(f'zlib error: {e}') from None
        else:
            raise e
    except ImportError:
        raise e

Using raise e adds an extra traceback frame at the re-raise site. A bare
raise would keep the traceback cleaner while preserving the original exception
and its traceback.

CPython versions tested on:

3.14, CPython main branch

Operating systems tested on:

Windows

Linked PRs

• gh-149760:Fix TarFile.next() to reraises non-zlib exceptions with a bare raise instead of raise e. #149761
• gh-149760: Improve exception tracebacks from TarFile.next() #157257