[elpa] externals/org d8606c3 1/3: org-element--cache-sync: Handle silent changes for non-latin input methods

[ELPA Syncer]

branch: externals/org
commit d8606c316ee3d27ddfb38705f1c15e24087f0ee3
Author: Ihor Radchenko <yantar92@gmail.com>
Commit: Ihor Radchenko <yantar92@gmail.com>

    org-element--cache-sync: Handle silent changes for non-latin input methods
    
    * lisp/org-element.el (org-element--cache-sync): Detect silent changes
    in buffer made by quail.el when non-latin input methods are active.
    These silent changes do not modify the buffer, but only change
    `buffer-chars-modified-tick' and do no affect element cache.  Note
    that the detection uses heuristics.
    
    Fixes https://list.orgmode.org/87sfw2luhj.fsf@localhost/T/#you
---
 lisp/org-element.el | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/lisp/org-element.el b/lisp/org-element.el
index c98e95b..6c956d6 100644
--- a/lisp/org-element.el
+++ b/lisp/org-element.el
@@ -5835,8 +5835,21 @@ updated before current modification are actually 
submitted."
     (with-current-buffer (or (buffer-base-buffer buffer) buffer)
       ;; Check if the buffer have been changed outside visibility of
       ;; `org-element--cache-before-change' and 
`org-element--cache-after-change'.
-      (if (/= org-element--cache-change-tic
-             (buffer-chars-modified-tick))
+      (if (and (/= org-element--cache-change-tic
+                  (buffer-chars-modified-tick))
+               ;; FIXME: Below is a heuristics noticed by observation.
+               ;; quail.el with non-latin input does silent
+               ;; modifications in buffer increasing the tick counter
+               ;; but not actually changing the buffer text:
+               ;; https://list.orgmode.org/87sfw2luhj.fsf@localhost/T/#you
+               ;; 
https://lists.gnu.org/archive/html/bug-gnu-emacs/2021-11/msg00894.html
+               ;; However, the values of `buffer-chars-modified-tick'
+               ;; and `buffer-modified-tick' appear to be same after
+               ;; the quail.el's changes in buffer.  We do not
+               ;; consider these exact changes as a dangerous silent
+               ;; edit.
+               (/= (buffer-chars-modified-tick)
+                  (buffer-modified-tick)))
           (progn
             (org-element--cache-warn "Unregistered buffer modifications 
detected. Resetting.
 If this warning appears regularly, please report it to Org mode mailing list 
(M-x org-submit-bug-report).