Initial commit of typescript-tree-sitter-mode

Author: theothornhill

typescript-tree-sitter.el

@@ -0,0 +1,144 @@
+;;; typescript-tree-sitter.el --- tree sitter support for Typescript  -*- lexical-binding: t; -*-
+
+;; Copyright (C) Theodor Thornhill
+
+;; Author     : Theodor Thornhill <[email protected]>
+;; Maintainer : Jostein Kjønigsen <[email protected]>
+;;              Theodor Thornhill <[email protected]>
+;; Created    : April 2022
+;; Modified   : 2022
+;; Version    : 0.4
+;; Keywords   : typescript languages
+;; X-URL      : https://github.com/emacs-typescript/typescript.el
+;; Package-Requires: ((emacs "26.1") (tree-sitter "0.12.1") (tree-sitter-indent "0.1") (tree-sitter-langs "0.9.1"))
+
+;; 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/>.
+
+
+;;; Code:
+(require 'cl-lib)
+(require 'cl-extra)
+(require 'seq)
+
+(when t
+  ;; In order for the package to be usable and installable (and hence
+  ;; compilable) without tree-sitter, wrap the `require's within a dummy `when'
+  ;; so they're only executed when loading this file but not when compiling it.
+  (require 'tree-sitter)
+  (require 'tree-sitter-hl)
+  (require 'tree-sitter-indent)
+  (require 'tree-sitter-langs))
+;; Vars and functions defined by the above packages:
+(defvar tree-sitter-major-mode-language-alist) ;From `tree-sitter-langs'.
+(declare-function tree-sitter-indent-mode "ext:tree-sitter-indent")
+(declare-function tree-sitter-indent-line "ext:tree-sitter-indent")
+(declare-function tree-sitter-hl-mode "ext:tree-sitter-hl")
+(declare-function tsc-node-end-position "ext:tree-sitter")
+(declare-function tsc-node-start-position "ext:tree-sitter")
+
+(defvar typescript-tree-sitter-syntax-table)
+(defvar typescript-tree-sitter-map)
+
+;;; Tree-sitter indentation
+
+(defgroup typescript-tree-sitter-indent nil "Indent lines using Tree-sitter as backend"
+  :group 'tree-sitter)
+
+(defcustom typescript-tree-sitter-indent-offset 2
+  "Indent offset for typescript-tree-sitter-mode."
+  :type 'integer
+  :group 'typescript)
+
+(defvar tree-sitter-indent-typescript-tree-sitter-scopes
+  '((indent-all
+     ;; these nodes are always indented
+     . ("."))
+    (indent-rest
+     ;; if parent node is one of these and node is not first → indent
+     . ())
+    (indent-body
+     ;; if parent node is one of these and current node is in middle → indent
+     . (statement_block
+        array_pattern
+        arguments
+        parenthesized_expression
+        jsx_element
+        jsx_self_closing_element
+        jsx_opening_element))
+    (paren-indent
+     ;; if parent node is one of these → indent to paren opener
+     . ())
+    (align-char-to
+     ;; chaining char → node types we move parentwise to find the first chaining char
+     . ())
+    (aligned-siblings
+     ;; siblings (nodes with same parent) should be aligned to the first child
+     . ())
+    (multi-line-text
+     ;; if node is one of these, then don't modify the indent
+     ;; this is basically a peaceful way out by saying "this looks like something
+     ;; that cannot be indented using AST, so best I leave it as-is"
+     . ())
+    (outdent
+     ;; these nodes always outdent (1 shift in opposite direction)
+     . ())
+    (align-to-node-line
+     ;; this group has lists of alist (node type . (node types... ))
+     ;; we move parentwise, searching for one of the node
+     ;; types associated with the key node type. if found,
+     ;; align key node with line where the ancestor node
+     ;; was found.
+     . ()))
+  "Scopes for indenting Typescript.")
+
+(defvar typescript-tree-sitter-mode-map
+  (let ((map (make-sparse-keymap)))
+    map)
+  "Keymap used in typescript-tree-sitter buffers.")
+
+(defvar typescript-tree-sitter-mode-syntax-table
+  (let ((table (make-syntax-table)))
+    (modify-syntax-entry ?@ "_" table)
+    table))
+
+;;;###autoload
+(define-derived-mode typescript-tree-sitter-mode prog-mode "Typescript"
+  "Major mode for editing Typescript code.
+
+Key bindings:
+\\{typescript-tree-sitter-mode-map}"
+  :group 'typescript
+  :syntax-table typescript-tree-sitter-mode-syntax-table
+
+  (setq-local indent-line-function #'tree-sitter-indent-line)
+  ;; (setq-local beginning-of-defun-function #'typescript-beginning-of-defun)
+  ;; (setq-local end-of-defun-function #'typescript-end-of-defun)
+
+  ;; https://github.com/ubolonton/emacs-tree-sitter/issues/84
+  (unless font-lock-defaults
+    (setq font-lock-defaults '(nil)))
+
+  ;; Comments
+  (setq-local comment-start "// ")
+  (setq-local comment-start-skip "\\(?://+\\|/\\*+\\)\\s *")
+  (setq-local comment-end "")
+
+  (tree-sitter-hl-mode)
+  (tree-sitter-indent-mode))
+
+(add-to-list 'tree-sitter-major-mode-language-alist '(typescript-tree-sitter-mode . tsx))
+
+(provide 'typescript-tree-sitter)
+
+;;; typescript-tree-sitter.el ends here