From c98bc9821f4a402d5fda67fe141ed34622c50e4f Mon Sep 17 00:00:00 2001
From: Phillip Lord <phillip.lord@russet.org.uk>
Date: Fri, 17 Jun 2016 22:34:50 +0100
Subject: [PATCH] Ensure undo-boundary after all commands
* lisp/simple.el (undo-auto--boundaries): Ensure an undo-boundary after
every command whether it (apparently) changes the buffer or not.
See Bug#23785 for discussion.
---
lisp/simple.el | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/lisp/simple.el b/lisp/simple.el
index a502448b31c..bc3e7b83b8d 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2884,6 +2884,10 @@ REASON describes the reason that the boundary is being added; see
"Check recently changed buffers and add a boundary if necessary.
REASON describes the reason that the boundary is being added; see
`undo-last-boundary' for more information."
+ ;; (Bug #23785) All commands should ensure that there is an undo
+ ;; boundary whether they have changed the current buffer or not.
+ (when (eq cause 'command)
+ (add-to-list 'undo-auto--undoably-changed-buffers (current-buffer)))
(dolist (b undo-auto--undoably-changed-buffers)
(when (buffer-live-p b)
(with-current-buffer b
--
2.39.5