py_lsp.nvim

What is py_lsp?

py_lsp.nvim is a neovim plugin that helps with using the lsp feature for python development.

It tackles the problem about the activation and usage of python virtual environments and conda environments for the nvim lsp.

Includes optional support for nvim-notify plugins (for custom popup information) and nvim-lsp-installer for LSP detection. Includes a detection inside the Virtual Environment for the LSP presence as last fallback (before check in the host machine).

Installation

Using vim-plug:

Plug 'HallerPatrick/py_lsp.nvim'

Using packer.nvim:

use {
    'HallerPatrick/py_lsp.nvim',
    -- Support for versioning
    -- tag = "v0.0.1" 
}

Usage

Instead of initializing the server on your own, like in nvim-lspconfig, py_lsp is doing that for you.

Put this in your init.lua (or wrap in lua call for your init.vim)

require'py_lsp'.setup {
  -- This is optional, but allows to create virtual envs from nvim
  host_python = "/path/to/python/bin",
  default_venv_name = ".venv" -- For local venv
}

This minimal setup will automatically pass a python virtual environment path to the LSP client for completion/linting.

WARNING: py_lsp is currently not agnostic against other python lsp servers that are starting or attaching. Please be aware of other plugins, autostarting lsp servers.

Features

py_lsp exposes several commands that help with a virtual env workflow.

Command	Parameter	Usage
:PyLspCurrentVenv	No	Prints the currently used python venv
:PyLspDeactiveVenv	No	Shuts down the current LSP client
:PyLspReload	No	Reload LSP client with current python venv
:PyLspActivateVenv	venv name	Activates a virtual env with given name (default: 'venv'). This venv should lie in project root
:PyLspActivateCondaEnv	env name	Activates a conda env with given name (default: 'base'). Requires conda to be installed on the system
:PyLspCreateVenv	venv name	Creates a virtual env with given name (default: 'venv'). Requires host_python to be set and have virtualenv installed
:PyRun	Optional	Run files and modules from current virtuale env. If no arguments specified, will run current buffer
:PyLspFindVenvs	No	List all found Virtualenvs found by different strategies. Select and reload LSP

Most of these commands can be also run over a popup menu with :PyLspPopup.

PyRun

The :PyRun command uses the currently activated virtuale environment to either execute the current buffer on or the arguments passed to pather. If toggleterm is an available plugin the command is executed through a toggleterm terminal.

Configuration

The configurations are not sensible yet, and are suiting my setup. This will change.

Default:

Default Values:
    auto_source = true,
    language_server = "pyright",
    source_strategies = {"default", "poetry", "conda", "system"},
    capabilities = nil,
    host_python = nil,
    on_attach = nil,
    on_server_ready = nil
    default_venv_name = nil,
    pylsp_plugins = {}, // the table with the various pylsp plugins with their parameters
    venvs = {}

One can also provide settings like default_venv_name or source_stragie in a pyproject.toml file, to have a per-project setting which venv to use.

[tool.py_lsp]
default_venv_name = "my_conda_venv"

# Beware, that the source_strategie is a string, not a table
source_strategie = "conda"

This requires a plugin for loading toml files, so include the following in your nvim config: Lazy:

{
    "HallerPatrick/py_lsp.nvim",
    dependencies = { "dharmx/toml.nvim" },
    ...
}

Other Language servers

I am using pyright and therefore works well with pyright. When using a not registered language server like jedi-language-server you can register it like following:

local nvim_lsp_configs = require "lspconfig.configs"

nvim_lsp_configs["jedi_language_server"] = {
    default_config = {
        cmd = {"jedi-language-server"},

        -- Depending on your environment
        root_dir = nvim_lsp.util.root_pattern(".git", "setup.py",
                                              "pyproject.toml"),
        filetypes = {"python"}
    }
}

local capabilities = require('cmp_nvim_lsp').update_capabilities(vim.lsp
                                                                     .protocol
                                                                     .make_client_capabilities())

require("py_lsp").setup({
    language_server = "jedi_language_server",
    capabilities = capabilities
})

Todo

• Support for different environment systems:
  • virtualenvwrapper
  • Pipenv
• Agnostic against other python lsp server