From: Yuan Fu <casouri@gmail.com>
Date: Mon, 24 Oct 2022 01:51:35 +0000 (-0700)
Subject: * lisp/treesit.el (treesit-parser-range-on): New function.
X-Git-Tag: emacs-29.0.90~1793
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=1787e651d376486909e736478b1be92c949a368d;p=emacs.git

* lisp/treesit.el (treesit-parser-range-on): New function.
---

diff --git a/lisp/treesit.el b/lisp/treesit.el
index 16c5aab8507..0df9b6c6876 100644
--- a/lisp/treesit.el
+++ b/lisp/treesit.el
@@ -298,6 +298,21 @@ in-order.  START and END are passed to each range function."
   (dolist (range-fn treesit-range-functions)
     (funcall range-fn (or start (point-min)) (or end (point-max)))))
 
+(defun treesit-parser-range-on (parser beg &optional end)
+  "Check if PARSER's range covers the portion between BEG and END.
+
+If it does, return the range covering that portion in the form
+of (RANGE-BEG . RANGE-END), if not, return nil.  If nil or
+omitted, default END to BEG."
+  (let ((ranges (treesit-parser-included-ranges parser))
+        (end (or end beg)))
+    (if (null ranges)
+        (cons (point-min) (point-max))
+      (cl-loop for rng in ranges
+               if (<= (car rng) beg end (cdr rng))
+               return rng
+               finally return nil))))
+
 ;;; Font-lock
 
 (define-error 'treesit-font-lock-error