Ignore existing venv dir when PIPENV_VENV_IN_PROJECT is false

[arnaud-dezandee]

Hi !

The issue

I have a project installed on my host (macOS) which use the PIPENV_VENV_IN_PROJECT=1 env vars to install pipenv deps into my_project/.venv folder. Now I am working on a docker-compose setup, which has another Python version, with the local project bind mounted into the container.

In the Dockerfile, I am only copying Pipfiles and running pipenv install with PIPENV_VENV_IN_PROJECT=0 so that the venv is built specifically for this container env and embedded in the docker image.

With my local code mounted inside the container, alongside the host .venv, I was expecting pipenv commands to follow PIPENV_VENV_IN_PROJECT=0 set inside the container context and ignore the mounted .venv.

Turns out, it is not working even though the documentation clearly states:

self.PIPENV_VENV_IN_PROJECT = get_from_env("VENV_IN_PROJECT")
""" When set True, will create or use the ``.venv`` in your project directory.
When Set False, will ignore the .venv in your project directory even if it exists.
If unset (default), will use the .venv of project directory should it exist, otherwise
will create new virtual environments in a global location.
"""

This issue was already raised in this comment #2763 (comment)

The fix

Tweaked the get_location_for_virtualenv function to adjust loading priorities based on the expected behavior and added an integration test

[matteius]

Please add a behavior news fragment since this is technically a behavior change.

[arnaud-dezandee]

Hello @matteius, sorry for the delay. I was about to add the fragment today. Anyway, thanks for the merge