Julia major mode using tree-sitter

Emacs major mode for the Julia programming language using tree-sitter for font-lock, indentation, imenu, and navigation. It is derived from julia-mode.

Installation

Dependencies

This package requires:

1. Emacs 29 or newer built with tree-sitter support;
2. Julia tree-sitter grammar; and
3. The package julia-mode.

Installation from MELPA

julia-ts-mode is available on MELPA. The recommended way to install it is using use-package. The following code installs julia-ts-mode and selects it as the default major mode for Julia files:

(use-package julia-ts-mode
  :ensure t
  :mode "\\.jl$")

Installation from source

You can install this package from source by cloning this directory and adding the following lines to your Emacs configuration:

(add-to-list 'load-path "<path to the source-code tree>")
(require 'julia-ts-mode)

Installing Julia Tree-Sitter Grammar

The recommended way to install the tree-sitter grammar is using the package treesit-auto. In this case, the Julia tree-sitter grammar will be automatically downloaded and compiled when a Julia file is opened using the major mode julia-ts-mode. For more information on how to install and configure treesit-auto, check the package documentation.

Upgrading grammar after a package update

Note that the tree-sitter grammar for Julia is under active development, and breaking changes are often introduced between versions. To provide maximum compatibility, the exact version of the grammar library is fixed in julia-ts-mode.el, with planned regular updates to both the grammar version and the tree-sitter queries built on top of it. However, the grammar library itself isn't updated automatically by Emacs. If, after a julia-ts-mode package update, you get some quirky tree-sitter error messages, and font-locking fails to work in a julia-ts-mode buffer, run M-x treesit-install-language-grammar RET julia RET to upgrade the grammar library. This should resolve the issues.

LSP Configuration

This mode is derived from julia-mode. Hence, most of the feature available for it will also work in julia-ts-mode. However, the LSP requires additional configuration. First, it is necessary to install the package lsp-julia, and apply the desired configuration as stated in its documentation. Afterward, add the following code to your Emacs configuration file:

(add-to-list 'lsp-language-id-configuration '(julia-ts-mode . "julia"))
(lsp-register-client
(make-lsp-client :new-connection (lsp-stdio-connection 'lsp-julia--rls-command)
                 :major-modes '(julia-mode ess-julia-mode julia-ts-mode)
                 :server-id 'julia-ls
                 :multi-root t))