No `VIRTUAL_ENV` variable available?

Description: In an activated Python virtual environment (venv), the environment variable VIRTUAL_ENV contains the path to the base of the venv. That variable doesn’t exists, and it doesn’t seem possible to activate the environment in the action either? I could pass in that variable but then I’d have to make an assumption about where this Action installs Python on the runner.

Action version: v3, latest

Platform:

• Ubuntu
• macOS
• Windows

Runner type:

• Hosted
• Self-hosted

Tools version: I tried with 3.9 and 3.10 and it failed for both.

Repro steps:
Failed activate:

• https://github.com/jenstroeger/python-package-template/runs/5686105935
• https://github.com/jenstroeger/python-package-template/runs/5686092462

No VIRTUAL_ENV variable:

• https://github.com/jenstroeger/python-package-template/runs/5686059948

Expected behavior: Either being able to activate the environment (which is tricky from an Action considering the differences between Windows (Scripts/ folder) and Linux/Mac (bin/ folder). Ideally, the VIRTUAL_ENV would be set?

Actual behavior: The variable isn’t available.

[vsafonkin]

@jenstroeger, it’s correct. You can use GITHUB_ENV to pass values between steps.

- name: venv activate Linux
  run: |
    mkdir test-venv
    cd test-venv
    python -m venv .
    source ./bin/activate
    echo "VIRTUAL_ENV: $VIRTUAL_ENV"
    echo "VIRTUAL_ENV=$VIRTUAL_ENV" >> $GITHUB_ENV

- name: test
  run: |
    echo "VIRTUAL_ENV: $VIRTUAL_ENV"

[vsafonkin]

@jenstroeger, the setting up and activation of venv are not in scope of setup-python action because using of venv is not mandatory for all python developers, someone can use the other tools and packages. The main goal of setup-python action is installation of required python version on the runner.