Subject: bug#15760: closed (Re: bug#15760: Bug #15760: 24.3; move-to-window-line goes to wrong line)

From: [email-masked] (GNU bug Tracking System)
Date: Mon, 27 Jun 2016 15:35:02 +0000

Your bug report

#15760: 24.3; move-to-window-line goes to wrong line

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
15760: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15760
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#15760: Bug #15760: 24.3; move-to-window-line goes to wrong line
From: Eli Zaretskii <[email-masked]>
To: Noam Postavsky <[email-masked]>
Cc: [email-masked], [email-masked]
Date: Mon, 27 Jun 2016 18:33:38 +0300
List-Id: <debbugs-submit.debbugs.gnu.org>

> From: Noam Postavsky <[email-masked]>
> Date: Sun, 26 Jun 2016 22:35:34 -0400
> Cc: John Hagerman <[email-masked]>, [email-masked]
> 
> >> Ah, the line is indeed fully visible according to
> >> pos-visible-in-window-p. But trying with emacs 24.5 the problem
> >> doesn't occur, so actually this must be a bug that was fixed sometime
> >> between 24.3 and 24.5.
> >
> > I think I see it in 25.0.95.  I will take a look.
> 
> Oh yeah, I see it too. Regression :(

Not a regression, actually.  There was a subtle off-by-one error in a
subroutine of move-to-window-line, which was present there since the
day the function was written.  I see the same problem in 24.5.  Now
hopefully fixed on master.

I also updated the documentation, which was very vague about the exact
meaning of the argument -1.

Thanks.

Subject: 24.3; move-to-window-line goes to wrong line
From: John Hagerman <[email-masked]>
To: "[email-masked]" <[email-masked]>
Date: Wed, 30 Oct 2013 18:22:42 +0000
List-Id: <debbugs-submit.debbugs.gnu.org>

Using X Windows, I start 'emacs -Q' and get a window of height "30".  I
need a buffer with more lines than window height, so I enter 35 lines
into an empty buffer.  At that point the last line of the buffer is
somewhere in the middle of the window.  Since 'point' is at the end of
the buffer, doing (move-to-window-line -1) does not move point, as
expected.  Then, since 'point' is at the end of the buffer, doing ESC -
^L adjusts the display so the last line of the buffer is on the last
line of the window.  Now doing (move-to-window-line -1) _does_ move
point, to the previous line.  I believe this is incorrect behavior.
Then, since 'point' has moved, doing ESC - ^L puts the second-to-last
line of the buffer on the last line of the window.  And now doing
(move-to-window-line -1) does not move point, as expected.

Dribble file (unprintable chars edited to, eg, "^X"):
^Xbfoo<return>1<return>2<return>3<return>4<return>5<return>6<return>7<return>8<return>9<return>0<return>1<return>2<return>3<return>4<return>5<return>6<return>7<return>8<return>9<return>0<return>1<return>2<return>3<return>4<return>5<return>6<return>7<return>8<return>9<return>0<return>1<return>2<return>3<return>4<return>5<return><escape>-1<escape>xmove-to-window-line<return><escape>-^L<escape>-1<escape>xmove-to-window-line<return><escape>-^L<escape>-1<escape>xmove-to-window-line<return>^X^C

Thanks ~ John

In GNU Emacs 24.3.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4)
 of 2013-05-03 on depbldrh55
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
System Description:	Red Hat Enterprise Linux Client release 5.7 (Tikanga)

Configured using:
 `configure '--prefix=/depot/emacs-24.3' '--with-gif=no'
 '--with-x-toolkit=yes''

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

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  tooltip-mode: t
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  tool-bar-mode: t
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  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
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