Setup Emacs for Python with Treesitter and Eglot

emacs-python-treesitter-eglot.org

Emacs, Python, Treesitter and Eglot

Treesitter (“better”/faster syntax highlighting)

1. Make sure you have Emacs with treesitter support:

   M-: (treesit-available-p) RET should return t

2. Make sure you have installed python treesitter grammar
   • Windows: download libtree-sitter-python.dll from https://corwin.bru.st/emacs-tree-sitter/ into ~/.emacs.d/tree-sitter/
   • GNU/Linux: run M-x treesit-install-language-grammar RET type python RET and do a couple of additional y for default options. You will need to have git and C/Cpp compiler available as it would download repo and build grammar library.
3. Open python file and do M-x python-ts-mode RET to activate treesitter python mode.
4. Press C-h m to see if python treesitter is in place, third line should state:

   Major mode for editing Python files, using tree-sitter library.
       

5. Optional, auto enable treesitter for python:

   (setq major-mode-remap-alist
         '((python-mode . python-ts-mode)))
       

Eglot (Emacs LSP client)

1. Install eglot (not needed for Emacs 29.1)
2. Install python language server, example for Debian 12:

   $ sudo apt install python3-pylsp
       

   For others, check the their corresponding docs. Or use venv.

3. In python buffer run M-x eglot RET

It should state it is successfully connected.

Completion UI

For completion UI corfu might work. Install and enable with (global-corfu-mode).

Use (setq tab-always-indent 'complete) to let you TAB to trigger completion. Default is C-M-i.

$ sudo apt install python3-pylsp

Under python-ts-mode, I can not turn on eglot, for it will report:

[eglot] Sorry, couldn't guess for `python-ts-mode'!
Enter program to execute (or <host>:<port>): 

Solved:
It turns out that my eglot version is too old. The built-in version will support all xxx-ts-mode.