python / python/cpython

zipfile.Path.is_symlink() raises KeyError for missing entries

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stdlib type-bug
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Python
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Description

Summary

zipfile.Path.is_symlink() raises KeyError for a path that is not present in the archive, while the neighboring path predicates return booleans for the same object. This makes is_symlink() leak ZipFile.getinfo() lookup behavior instead of behaving like a predicate, and it differs from pathlib.Path.is_symlink() on a missing filesystem path.

Code path

  • Lib/zipfile/_path/__init__.py:395-402: Path.is_dir(), Path.is_file(), and Path.exists() use string/path-state checks and return booleans.
  • Lib/zipfile/_path/__init__.py:413-419: Path.is_symlink() calls self.root.getinfo(self.at) directly before checking the mode bits.
  • Lib/zipfile/__init__.py:2126-2133: ZipFile.getinfo() raises KeyError when the member name is absent.

Steps to reproduce

I reproduced this directly on Python 3.13.13 and on a local CPython main checkout built out-of-tree.

Minimal reproducer:

import io
import zipfile

buf = io.BytesIO()
with zipfile.ZipFile(buf, "w") as zf:
    zf.writestr("present.txt", b"x")

buf.seek(0)
with zipfile.ZipFile(buf) as zf:
    p = zipfile.Path(zf) / "missing.txt"
    print(p.exists(), p.is_file(), p.is_dir())
    print(p.is_symlink())

Observed on Python 3.13.13:

python: 3.13.13 | packaged by Anaconda, Inc. | (main, Apr 14 2026, 06:14:06) [Clang 20.1.8 ]
zipfile module: <python-3.13.13-env>/lib/python3.13/zipfile/__init__.py
exists/is_file/is_dir: False False False
is_symlink exception: KeyError: "There is no item named 'missing.txt' in the archive"

Observed on CPython main:

commit: 564c58c718bc3de9cf3d9bc20cdc06317411c1cd
python: 3.16.0a0 (heads/main-dirty:564c58c, Jul  1 2026, 17:29:34) [Clang 21.0.0 (clang-2100.1.1.101)]
zipfile module: <checkout>/Lib/zipfile/__init__.py
exists/is_file/is_dir: False False False
is_symlink exception: KeyError: "There is no item named 'missing.txt' in the archive"

The CPython main result was produced with the interpreter built from that checkout, without monkeypatching or shims.
The source checkout used for the anchors above was clean (git status --short produced no output); build artifacts were kept out-of-tree.

Expected behavior

zipfile.Path.is_symlink() should return False for a path that is not present in the archive. This matches the behavior of pathlib.Path.is_symlink() for a missing filesystem path and the boolean-predicate behavior of zipfile.Path.exists(), zipfile.Path.is_file(), and zipfile.Path.is_dir() on the same missing archive path.

Actual behavior

zipfile.Path.is_symlink() raises:

KeyError: "There is no item named 'missing.txt' in the archive"

Existing coverage

Related but not duplicate:

  • #119588 / #119591 added zipfile.Path.is_symlink(), but did not cover missing archive paths.
  • #133324 discusses broader file type semantics for zipfile.Path, including symlinks and directories, but does not cover this missing-path KeyError root cause.

Suggested fix

Return False before calling getinfo() when the Path does not correspond to an archive member, or otherwise catch the KeyError from getinfo() and convert it to False for this predicate.

Suggested tests

  • Add a zipfile.Path test where Path(zf) / "missing.txt" returns False from is_symlink().
  • Keep coverage that existing symlink entries still return True.
  • Consider also covering the archive root path if it is expected to behave as a non-symlink directory.

Submitted with Codex.

Linked PRs
  • gh-152924

Contributor guide

Open the contributing guide

First steps

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  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with Lib/zipfile/_path/init.py:413-419 and compare is_symlink() with the neighboring predicates at lines 395-402. Review the existing zipfile.Path tests and add coverage for a missing member, while keeping the existing symlink case covered; done means missing paths return False without changing valid symlink behavior.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
backend
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
25/100

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