How to set python interpreter in neovim for python language server depending on pyenv / virtualenv

This is not actually an answer, there is this issue in nvim-lsp where they explore some alternatives, it turns out nvim (or pyright, I don't know exactly) don't respect/load pyenv local .python-version file. An alternative is to use regular venv. Using pyenv shell myvenv before running nvim also works, but it goes against the convenience of .python-version file. Maybe there is a way to load the correct venv with some scripts in bashrc/zshrc/config.fish, but again this is not that convenient, IMHO.

https://github.com/neovim/nvim-lspconfig/issues/717

EDIT: Found a good solution

There is a simple way to get pyright work with pyenv virtualenvs:

Create pyrightconfig.json file in root directory of your project, and paste the following, relacing USERNAME and MY-VENV with your user and venv, supposing your pyenv is installed in ~/.pyenv. It adds another file beyond .python-version, but its easy and don't mess with your shell configs.

{
    "venvPath": "/home/USERNAME/.pyenv/versions/",
    "venv": "MY-VENV"
}

You can check full doc here: https://github.com/microsoft/pyright/blob/master/docs/configuration.md

EDIT 2: Checkout this plugin pyenv-pyright I created. With it you can setup pyright to use pyenv venvs with only one command:

pyenv local my-venv
pyenv pyright

or

pyenv pyright my-venv

This will automatically create/update pyrightconfig.json file with the pyenv virtualenv of your choice. Its a convenient way to overcome neovim+pyright+pyenv virtualenvs setup. https://github.com/alefpereira/pyenv-pyright

TLDR;

echo '{ "venvPath": ".", "venv": ".venv" }' >> pyrightconfig.json

It works with the default pyenv and poetry setup.

I failed to make other options work, so I use

pyenv shell [virtual_env_name]

and it works for me.

I use LazyVim as nvim distribution, and in their setup they include venv-selector plugin. It has worked quite well to me out of the box.

seems like this config is working for me in nvim to activate either a virtual env, a pyenv env, or fallback to the standard python installation

in my init.lua

local function get_python_path()
    -- Use activated virtualenv
    if vim.env.VIRTUAL_ENV then
        return vim.env.VIRTUAL_ENV .. "/bin/python"
    end

    -- Find and use pyenv environment
    local pyenv_path = vim.fn.system("pyenv which python"):gsub("\n", "")
    if vim.fn.filereadable(pyenv_path) == 1 then
        return pyenv_path
    end

    -- Default to system Python
    return vim.fn.exepath("python3") or vim.fn.exepath("python") or "python"
end

require('lspconfig').pyright.setup({
    before_init = function(_, config)
        config.settings.python.pythonPath = get_python_path()
    end
})