python: avoid using existing virtual env or poetry binary

[bobvanderlinden]

Currently poetry is called in one instance with just poetry. There were cases where the poetry binary from devenv's root project leaked into the devenv of the python-poetry test. This often is not a problem, but in this case it was a poetry version that was built against a different glibc, resulting in an error.

I've tried to harden the poetry module a bit more by explicitly calling all executables to avoid leakage of executables from a parent environment.

While debugging also found a minor issue when manually executing poetry after removing .venv, poetry will create a new .venv directory. In this case devenv should remove it and create a new symlink. This is what ln -sf was meant to do, however it instead created a symlink inside the .venv directory. I tried to avoid this by using --no-target-directory.

Lastly, this resets the VIRTUAL_ENV so that poetry won't try to use python from a VIRTUAL_ENV that was already active before devenv shell started.

[domenkozar]

Seems to still have the same failure

[bobvanderlinden]

Seems to still have the same failure

I had a hard time understanding what was going wrong. I think it's a combination:

It seems that all examples (that I run using devenv-test-example) are run against devenv modules from github:cachix/devenv. To circumvent this during development I used:

inputs:
  nixpkgs:
    url: github:NixOS/nixpkgs/nixpkgs-unstable
  devenv:
    url: /home/bob.vanderlinden/projects/devenv/src/modules

Next it seemed as it poetry would default to using a different Python version than what was in PATH. It used the one from the devenv root's venv. Unsetting VIRTUAL_ENV seemed to fix the problem locally.

I had a hard time getting stable results from the tests, as there are numerous factors that affect the test:

• Am I in a devenv of ~/projects/devenv or not? (if not, it already worked)
• Is there a lock file still in examples/python-poetry from a previous debug session?
• Have I still got a devenv entry in examples/python-poetry/devenv.yaml?

Might need to look into the tests for a solution.

[bobvanderlinden]

Could you try rerunning CI?

[bobvanderlinden]

Yay, it succeeds now 👍 Just MySQL that is still failing.

[bobvanderlinden]

Thanks for your patience

[domenkozar]

Thanks for fixing this :)