GNU bug report logs - #9607
incorrect behavior with "automatic-hscroll-mode nil" in ncurses/vt220 text operation; wrong in 23 but ok in 22.1

Previous Next

Package: emacs;

Reported by: David Lawless <david_lawless <at> flumedata.com>

Date: Mon, 26 Sep 2011 21:24:02 UTC

Severity: normal

Done: Eli Zaretskii <eliz <at> gnu.org>

Bug is archived. No further changes may be made.

Full log


View this message in rfc822 format

From: Eli Zaretskii <eliz <at> gnu.org>
To: Glenn Morris <rgm <at> gnu.org>
Cc: 9607 <at> debbugs.gnu.org, david_lawless <at> flumedata.com
Subject: bug#9607: incorrect behavior with "auto-hscroll-mode nil" in ncurses/vt220 text operation; wrong in 23 but ok in 22.1
Date: Tue, 27 Sep 2011 02:07:20 -0400
> From: Glenn Morris <rgm <at> gnu.org>
> Date: Tue, 27 Sep 2011 00:01:50 -0400
> Cc: David Lawless <david_lawless <at> flumedata.com>
> 
> emacs -Q --eval '(setq auto-hscroll-mode nil)'
> 
> Evaluate:
> (dotimes (j 5)
>   (insert "\n")
>   (dotimes (i 10)
>     (insert "0123456890 ")))
> 
> Put point at start of first line of digits.
> M-x scroll-left RET y
> ;; Window now scrolled to right-hand end of lines
> Down arrow  ; first time is ok
> Down arrow
>   -> second time window scrolls back to left-hand end of line
> 
> 
> (setq line-move-visual nil)
> 
> avoids the problem.
> 
> I guess it's related to the 2009-07 changes to line-move-visual for hscroll.

The problem is that line-move-visual assumes that the move begins with
cursor positioned at point, which is false when auto-hscroll-mode is
turned off and point is scrolled out of view.

Before I dive into this mess (again), do we even want to support
auto-hscroll-mode nil _and_ visual line movement?  What if we tell
line-move to invoke logical line movement instead when
auto-hscroll-mode is off?  Would someone object?




This bug report was last modified 13 years and 273 days ago.

Previous Next


GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.