Question regarding the use of poetry in a CI workflow, and especially with caching

[Lucas-C]

• I have searched the issues of this repo and believe that this is not a duplicate.
• I have searched the documentation and believe that my question is not covered.

Issue

I have setup a GitHub Actions workflow for a Pelican plugin, using poetry as a dependency manager:
https://github.com/pelican-plugins/linkbacks/blob/master/.github/workflows/continuous-integration-workflow.yml

I have a special constraint: I need to install pelican in editable mode, to gain access to its tests.support package. Because currently poetry does not support to install dependencies in editable mode, I install my dev dependencies through a dev-requirements.txt file.

My approach works, but is a bit clunky:

• in order to cache dependencies, because poetry stores its dependencies in a virtualenv, I need 2 caching steps for both ~/.cache/pip & ~/.local/share/virtualenvs directories
• in order to call pylint, py.test or install dev-requirements.txt, I need to either prefix all commands by poetry run or else call source $(poetry env info --path)/bin/activate

poetry run is fine, but in a multi-lines workflow-step, where several commands would need to be executed in the virtualenv, entering it once can quickly becomes more efficient and less verbose IMHO

The whole workflow feels verbose and a bit cumbersome.

Would you please have any suggestion to improve this using poetry ?

And a more specific questions: are poetry developpers considering a no-virtualenv option, to install dependencies in ~/.cache/pip, which would make caching dependencies directories simpler in the case of a CI workflow, where there is not a need for virtual environments ?

[tony]

For GitHub actions users:

As of yesterday, @actions/setup-python@v3 supports this via v3.1.0: Release, Tag, actions/setup-python#281

steps:
- uses: actions/checkout@v3
- name: Install poetry
  run: pipx install poetry
- uses: actions/setup-python@v3
  with:
    python-version: '3.9'
    cache: 'poetry'
- run: poetry install
- run: poetry run pytest

If you see this via Google / Search and use gh actions, please search the tracker in case this ever changes. See also: #4205