Import "numpy" could not be resolved.

[ianyepan]

I'm using pyright as a LSP server in Emacs (via the lsp-mode package), and pyright is having trouble resolving pip3 installed packages like numpy or matplotlib. I checked numpy's installation location and it's under /home/ianpan/.local/lib/python3.8/site-packages, and when I ran pyright --verbose I do see this exact same path being found both under "Search paths found for configured python interpreter" and "Received 5 paths from interpreter".
In this case, is the pyrightconfig.json file still needed? If it is, what exactly should I put in the configuration file? All I need is for pyright to recognize my pip3 packages that installed "globally". Thanks in advance!

[erictraut]

You shouldn't need to specify your python environment in pyrightconfig.json. Python will use the default python environment configured in your shell. It does this by executing "python3" and running a small script in the selected Python interpreter to dump the paths the sys.path. From your description, it sounds like it is finding these properly. Those are the paths it lists under "Received 5 paths from interpreter".

When you say "having trouble resolving installed packages", what symptoms are you seeing?

With the --verbose flag enabled, pyright should output details when it attempts and fails to resolve a module. Are there any other clues in the verbose output?

[ianyepan]

Solved

Thanks for the fast reply @erictraut ! The symptoms I was seeing was an import resolution error, i.e. "Import numpy could not be resolved" etc. You mentioned that pyright executes "python3" and runs a small script in the selected Python interpreter to dump the paths the sys.path, and it turns out the command "python3" was exactly the problem! Emacs' LSP client for pyright "lsp-pyright" via "lsp-mode" defaults the command to "python", which points to python2 on my system. So after adding the following configuration in my Emacs' setting file init.el, the problem went away:

(setq lsp-pyright-python-executable-cmd "python3")

For fellow Emacs users seeking the answer, the following snippet is the complete solution to have Pyright working in Emacs:

(use-package python
  :config
  (setq python-shell-interpreter "python3"))

(use-package lsp-pyright
  :hook (python-mode . (lambda () (require 'lsp-pyright)))
  :init (when (executable-find "python3")
          (setq lsp-pyright-python-executable-cmd "python3")))