pip not available error with 2.1.0

[Alex-Izquierdo]

Hello.
We have detected an issue in https://github.com/ansible/event-driven-ansible CI pipelines where we are using tox-extra, after the release of 2.1.0 we have the issues with the missing pip module:

py39-unit: commands[1]> sh -c 'ansible-test units --color --requirements --target-python default -v --num-workers 1 --coverage --truncate 0 '
Configured locale: en_US.UTF-8
Loaded configuration: tests/config.yml
Creating container database.
Run command: /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py39-unit/bin/python3 -c 'import cryptography'
Installing requirements for Python 3.9
Stream command with data: /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py39-unit/bin/python3
Execute command: /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py39-unit/bin/python3 /tmp/ansible-test-7bbql1k9-pip.py install --disable-pip-version-check coverage==6.5.0
pip is unavailable: Error while finding module specification for 'pip.__main__' (ModuleNotFoundError: No module named 'pip')
A command failed with status 1: /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py39-unit/bin/python3 /tmp/ansible-test-7bbql1k9-pip.py install --disable-pip-version-check coverage==6.5.0
Run command with data: /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py39-unit/bin/python3
FATAL: Python 3.9 at "/home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda/.tox/py[39](https://github.com/ansible/event-driven-ansible/actions/runs/11916926494/job/33210780079#step:8:40)-unit/bin/python3" does not have pip available.
py39-unit: exit 1 (1.08 seconds) /home/runner/work/event-driven-ansible/event-driven-ansible/ansible_collections/ansible/eda> sh -c 'ansible-test units --color --requirements --target-python default -v --num-workers 1 --coverage --truncate 0 ' pid=5567

Pinning the version to the previous version, 2.0.2, solves the problem.

[ssbarnea]

The problem is not with tox-extra itself, is just that you used pip assuming that is installed in tox environments. That should not be a given. If you use pip ensure it is listed as a dependency.

deps =
  pip

Long story: uv default environments do not have pip. python venv environments do "usually" have it (behaviour can be changed with environment variables).

[cidrblock]

The issue here the addition of tox-uv requires that all users switch to UV or address CI issues related to pip.

This was a breaking change and not noted as such.