From: Po Lu <luangruo@yahoo.com>
Date: Sat, 20 Nov 2021 06:30:12 +0000 (+0800)
Subject: Use `xwidget-live-p' inside `xwidget-at'.
X-Git-Tag: emacs-29.0.90~2852^2~175
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=da508cf4bd437f8fd9a06fce33f6e62590e1e4d9;p=emacs.git

Use `xwidget-live-p' inside `xwidget-at'.

It should no longer be possible for Lisp code to abuse internal
xwidget state, or cause crashes with killed xwidgets and such,
so the pedantic checking done in this function is no longer
necessary.  (In fact, it is even wrong, as it won't catch
killed xwidgets.)

* lisp/xwidget.el (xwidget-at): Use `xwidget-live-p'.
---

diff --git a/lisp/xwidget.el b/lisp/xwidget.el
index 89f81bb8164..91580efa49a 100644
--- a/lisp/xwidget.el
+++ b/lisp/xwidget.el
@@ -58,6 +58,7 @@
 (declare-function xwidget-webkit-back-forward-list "xwidget.c" (xwidget &optional limit))
 (declare-function xwidget-webkit-estimated-load-progress "xwidget.c" (xwidget))
 (declare-function xwidget-webkit-set-cookie-storage-file "xwidget.c" (xwidget file))
+(declare-function xwidget-live-p "xwidget.c" (xwidget))
 
 (defgroup xwidget nil
   "Displaying native widgets in Emacs buffers."
@@ -77,12 +78,9 @@ This returns the result of `make-xwidget'."
 
 (defun xwidget-at (pos)
   "Return xwidget at POS."
-  ;; TODO this function is a bit tedious because the C layer isn't well
-  ;; protected yet and xwidgetp apparently doesn't work yet.
   (let* ((disp (get-text-property pos 'display))
-         (xw (car (cdr (cdr  disp)))))
-    ;;(if (xwidgetp  xw) xw nil)
-    (if (equal 'xwidget (car disp)) xw)))
+         (xw (car (cdr (cdr disp)))))
+    (when (xwidget-live-p xw) xw)))