Re: protobuf-ts-mode.el -- draft for new ts-mode

[Yuan Fu]

> On Jan 6, 2023, at 5:47 AM, mail@ookami.one wrote:
> 
> 
> It's quite a fun to implement new major modes using tree-sitter :)
> 
> Here is the file:
> 
> ;;; protobuf-ts-mode.el --- tree-sitter support for Protocol Buffers -*- 
> lexical-binding: t; -*-
> 
> ;; Author   : ookami <mail@ookami.one>
> ;; Created  : January 2023
> ;; Keywords : protobuf languages tree-sitter
> 
> ;; This program is free software; you can redistribute it and/or modify
> ;; it under the terms of the GNU General Public License as published by
> ;; the Free Software Foundation, either version 3 of the License, or
> ;; (at your option) any later version.
> 
> ;; This program is distributed in the hope that it will be useful,
> ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
> ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> ;; GNU General Public License for more details.
> 
> ;; You should have received a copy of the GNU General Public License
> ;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
> 
> ;;; Commentary:
> ;;
> 
> ;;; Code:
> 
> (require 'treesit)
> (eval-when-compile (require 'rx))
> 
> (defcustom protobuf-ts-mode-indent-offset 2
>  "Number of spaces for each indentation step in `protobuf-ts-mode'"
>  :type 'integer
>  :safe 'integerp
>  :group 'protobuf)
> 
> (defvar protobuf-ts-mode--indent-rules
>  `((proto
>     ((node-is ")") parent-bol 0)
>     ((node-is "}") parent-bol 0)
>     ((parent-is "service") parent-bol protobuf-ts-mode-indent-offset)
>     ((parent-is "rpc") parent-bol protobuf-ts-mode-indent-offset)
>     ((parent-is "message_body") parent-bol protobuf-ts-mode-indent-offset)
>     ((parent-is "enum_body") parent-bol protobuf-ts-mode-indent-offset))))
> 
> (defvar protobuf-ts-mode--keywords
>  '("optional" "repeated"
>    "message" "enum" "service" "rpc"
>    "syntax" "package" "import"
>    "option" "returns"))
> 
> (defvar protobuf-ts-mode--font-lock-settings
>  (treesit-font-lock-rules
>   :language 'proto
>   :feature 'comment
>   '((comment) @font-lock-comment-face)
> 
>   :language 'proto
>   :feature 'keyword
>   `([,@protobuf-ts-mode--keywords] @font-lock-keyword-face)
> 
>   :language 'proto
>   :feature 'string
>   '((string) @font-lock-string-face)
> 
>   :language 'proto
>   :feature 'type
>   '(
>     (service_name (identifier) @font-lock-type-face)
>     (message_name (identifier) @font-lock-type-face)
>     (enum_name (identifier) @font-lock-type-face)
>     (package (full_ident) @font-lock-type-face)
>     ((key_type) @font-lock-type-face)
>     ((type) @font-lock-type-face)
>     ((message_or_enum_type) @font-lock-type-face)
>     )
> 
>   :language 'proto
>   :feature 'function
>   '((rpc (rpc_name (identifier) @font-lock-function-name-face)))
> 
>   :language 'proto
>   :feature 'variable
>   '((identifier) @font-lock-variable-name-face)))
> 
> (defun protobuf-ts-mode--defun-name (node)
>  (treesit-node-text (treesit-search-subtree node "^identifier$" nil t) t))
> 
> ;;;###autoload
> (define-derived-mode protobuf-ts-mode prog-mode "Protocol-Buffers"
>  "Major mode for editing Protocol Buffers description language."
>  :group 'protobuf
>  (when (treesit-ready-p 'proto)
>    (treesit-parser-create 'proto)
> 
>    ;; Comments
>    (setq-local comment-start "/* ")
>    (setq-local comment-end "*/ ")
>    (setq-local comment-start-skip (rx (or (seq "/" (+ "/"))
>                                           (seq "/" (+ "*")))
>                                       (* (syntax whitespace))))
> 
>    ;; Font-lock
>    (setq-local treesit-font-lock-settings 
> protobuf-ts-mode--font-lock-settings)
>    (setq-local treesit-font-lock-feature-list
>                '(( comment)
>                  ( keyword string)
>                  ( type function variable)))
> 
>    ;; Imenu
>    (setq-local treesit-simple-imenu-settings
>                `(("Service" "\\`service_name\\'" nil nil)
>                  ("RPC" "\\`rpc_name\\'" nil nil)
>                  ("Message" "\\`message_name\\'" nil nil)
>                  ("Enum" "\\`enum_name'" nil nil)))
> 
>    ;; Indent
>    (setq-local treesit-simple-indent-rules protobuf-ts-mode--indent-rules)
> 
>    ;; Navigation
>    (setq-local treesit-defun-type-regexp
>                (rx (or "service"
>                        "rpc"
>                        "message"
>                        "enum")))
>    (setq-local treesit-defun-name-function 'protobuf-ts-mode--defun-name)
> 
>    (treesit-major-mode-setup)))
> 
> ;;;###autoload
> (add-to-list 'auto-mode-alist '("\\.proto\\'" . protobuf-ts-mode))
> 
> (provide 'protobuf-ts-mode)
> 
> ;;; protobuf-ts-mode.el ends here
> 

Looks good :-)

Yuan