How do you specify a path to a virtualenv?

[ryankask]

I'm trying to migrate my existing emacs setup to use python-language-server via eglot. I am currently using emacs with the emacs-jedi package. I'm able to pass a path to a virtualenv that ends up instantiating a Jedi environment like this: jedienv = jedi.create_environment(venv, safe=safe)

Is there a way to run python-language-server installed in one virtualenv (one that I use for packages requires across projects) but use a different one (ie the project virtualenv) for completion like is done above?

I've read through the existing issues but I'm not sure of the answer (#143, for example). Is it to set VIRTUAL_ENV when running pyls? Is there a way to pass a path instead like described above?

[ccordoba12]

At the moment there's no way to specify a path to a virtualenv, but we're working on it for a future release.

[ryankask]

Thanks for the quick response. I'll keep an eye on the repo.

[kawing-chiu]

Hi. Is there an open issue where I can track the progress of this?

[ccordoba12]

See #680.

[muffinmad]

@ryankask I'm using python-language-server via eglot. The solution is to set VIRTUAL_ENV variable before starting pyls:

(defvar mad/lsp-venv nil)

(require 'eglot)

(defun mad/eglot-pyls (_interactive)
  (when mad/lsp-venv
    ;; set your path to virtualenvs here
    (setenv "VIRTUAL_ENV" (concat "/Users/mad/.virtualenvs/" mad/lsp-venv)))
  (list "pyls"))

(add-hook 'eglot-server-initialized-hook #'(lambda (_server) (setenv "VIRTUAL_ENV")))

(add-to-list 'eglot-server-programs '(python-mode . mad/eglot-pyls))

To specify virtualenv I have .dir-locals.el in each project folder:

((nil . ((mad/lsp-venv . "envname"))))

Surely, you can specify virtualenv name in your way, like project directory name or something.

Jedi is read VIRTUAL_ENV variable: https://github.com/davidhalter/jedi/blob/03920502c42e2d77220cdc5f72fe790e6633ac44/jedi/api/environment.py#L150