[BUG] pyproject.toml: name, version not recognized (UNKNOWN 0.0.0)

setuptools version

62.1.0

Python version

3.10

OS

Ubuntu 22.04

Additional environment information

No response

Description

I recently started using Python 3.10 and found the pyproject.toml-based installation lacking. It now doesn’t reads name and version incorrectly:

pip install .

Defaulting to user installation because normal site-packages is not writeable
Processing /path/to/foobar
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Installing backend dependencies ... done
  Preparing metadata (pyproject.toml) ... done
Building wheels for collected packages: UNKNOWN
  Building wheel for UNKNOWN (pyproject.toml) ... done
  Created wheel for UNKNOWN: filename=UNKNOWN-0.0.0-py3-none-any.whl size=1227 sha256=sgrhihehihg
  Stored in directory: /path/to/.cache/pip/wheels/dsliughredshg
Successfully built UNKNOWN
Installing collected packages: UNKNOWN
  Attempting uninstall: UNKNOWN
    Found existing installation: UNKNOWN 0.0.0
    Uninstalling UNKNOWN-0.0.0:
      Successfully uninstalled UNKNOWN-0.0.0
Successfully installed UNKNOWN-0.0.0

Any idea why this might be? Perhaps package that’s missing in my 3.10 installation? I was surprised not to get an error message here either.

[tim-eves]

TLDR; On Ubuntu 22.04 (Jammy) ensure the environment variable DEB_PYTHON_INSTALL_LAYOUT=deb_system before installing a PEP621 compliant project with pip and setuptools.

This issue is occurring on Jammy because pip is unable to get an accurate list of system package directories to remove from its temporary build environment’s sys.path. As a result, when the temporary build env’s site/sitecustomize.py script runs /usr/lib/python3/dist-packages is left at the end of sys.path, before the overlay and normal paths are appended, thus placing it before those dirs in the search path. This means Jammy’s debian packaged setuptools (at version 59) is found and loaded ahead of whatever version the pyproject.toml requested. That version does not support PEP621 and is unable to extract name and version metadata, resulting in UNKNOWN-0.0.0.

This was not an issue on 20.04 (Focal) because the get_purelib and get_platlib logic inside pip/_internal/locations/__init__.py switched at runtime between using the older distutils and newer sysconfig modules for determining purelib and platlib paths. That choice is based on the value of sysconfig._PIP_USE_SYSCONFIG, which only defaults to False if the python version is less than 3.10. The older distuils knew how to deal with Debian’s install scheme layout, where the newer sysconfig doesn’t unless the env var DEB_PYTHON_INSTALL_LAYOUT is set to either deb or deb_system.

This means this is a distro configuration/packaging issue, but I’m posting this comment on a closed bug because this bug report comes up as the top result when googling for this issue.

[wimglenn]

I think this person had the same problem 😃 https://pypi.org/project/UNKNOWN/