Allow pipx to use active python (and pip)

[yozachar]

How would this feature be useful?

I'm using asdf to manage Python and pipx versions. I have created an asdf-pipx plugin, which executes just fine as long as you've python >= 3.7 on your system.

$ asdf which python
/home/us-er/.asdf/installs/python/3.11.3/bin/python

$ asdf which pip   
/home/us-er/.asdf/plugins/python/shims/pip

$ asdf which pipx
/home/us-er/.asdf/installs/pipx/1.2.0/bin/pipx

$ python --version
Python 3.11.3

$ pip --version   
pip 23.1.2 from /home/us-er/.asdf/installs/python/3.11.3/lib/python3.11/site-packages/pip (python 3.11)

$ pipx --version
1.2.0

$ pipx list          
nothing has been installed with pipx 😴

$ pipx install poetry
Fatal error from pip prevented installation. Full pip output in file:
    /home/us-er/.local/pipx/logs/cmd_2023-05-04_10.56.01_pip_errors.log

Error installing poetry.

$ cat /home/us-er/.local/pipx/logs/cmd_2023-05-04_10.56.01_pip_errors.log
PIP STDOUT
----------

PIP STDERR
----------
/home/us-er/.local/pipx/venvs/poetry/bin/python: No module named pip

Describe the solution you'd like

I'd like pipx to use the active python when installing python-applications.

Describe alternatives you've considered

Follow steps similar to what poetry has done:

• https://python-poetry.org/docs/configuration/#virtualenvsprefer-active-python-experimental
• fix: take virtualenvs.prefer-active-python into account on EnvManager.get() python-poetry/poetry#6986

---

Probably related to #387

[yozachar]

The issue was same as #278 #791 #888