Improve support for virtual env. (#26)

[sathlan]

When VIRTUAL_ENV variable is present in the environment, use "python mypy" instead of "mypy" so that library loaded in the VIRTUAL_ENV get correctly loaded. This works because python is always present is the VIRTUAL_ENV, but requires that mypy to be present is the directory where the caller is. In the context of the python-lsp-server and pipx install/inject this is the case.

[Richardk2n]

I assume you are talking about "python -m mypy"? "python mypy" wont work i think? "python -m mypy" would?

[sathlan]

Hi,

so python mypy does work, basically the code as provided work in my env. I agree though that the exact mechanism that makes it work doesn't feel very robust:

• the python-lsp-server runs from ~/.local/pipx/venvs/python-lsp-server/bin/ (installed with pipx install python-lsp-server) as it's called by pylsp from ~/.local/bin/pylsp:

~/.local/bin/pylsp -> ~/.local/pipx/venvs/python-lsp-server/bin/pylsp

• in that directory we have the binary "mypy" (installed with pipx inject pylsp-mypy):~/.local/pipx/venvs/python-lsp-server/bin/mypy : note that ~/.local/pipx/venvs/python-lsp-server/bin is not in the PATH, only ~/.local/bin/pylsp is. pipx install in the PATH only the first application installed, not the application provided by the injected package;
• hence running "python mypy" runs the equivalent of:

cd ~/.local/pipx/venvs/python-lsp-server/bin && python mypy (cwd is set by pylsp)

which is equivalent to:

~/src/my-nice-python-project/venvs/bin/python ~/.local/pipx/venvs/python-lsp-server/bin/mypy ^^^ this is overrided by the venvs loading

• that file which has a "main" section and make the whole process successful as:
  • python is coming from the currently defined venvs and thus has the right library defined.

At least that's how I understand it worked :), but it definitively worked in my env.

Don't have a ton of time to work on this, but happy to find a better way to achieve that.

[Richardk2n]

The feature set requested here is covered by the changes in #24 (as far as I am aware)