bug#367: compilation-scroll-output not working on certain long line

bug#367: compilation-scroll-output not working on certain long line

[Kevin Ryde]

[-- Attachment #1: Type: text/plain, Size: 2139 bytes --]

With foo.el and foo.pl below, running

	emacs -Q foo.el
	M-x eval-buffer

produces a compilation window showing only "xxx.xx" bits, where I hoped
setting compilation-scroll-output to `t' in foo.el would make it follow
the further output after that, ie. the "bar" lines (which you can see by
switching to the *compilation* buffer and scrolling down).

The foo.pl script is merely to print the provoking output.  It's a long
line arriving as its first 1024 bytes and then enough to just fill the
10-line compilation window.  During the second sleep the end of the
"xxx.xx" is the last line in the window.

I get the problem on both a console tty and under gtk X, and in both the
debian packaged 22.2 and my build of the current cvs.  It seems to
depend on the sleeps, ie. pauses in the output, so if you don't get the
effect you might try increasing them a bit.




In GNU Emacs 22.2.1 (i486-pc-linux-gnu, GTK+ Version 2.12.9)
 of 2008-04-27 on raven, modified by Debian
configured using `configure  '--build=i486-linux-gnu' '--host=i486-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var/lib' '--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes' '--enable-locallisppath=/etc/emacs22:/etc/emacs:/usr/local/share/emacs/22.2/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/22.2/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/22.2/leim' '--with-x=yes' '--with-x-toolkit=gtk' '--with-toolkit-scroll-bars' 'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -g -O2' 'LDFLAGS=-g' 'CPPFLAGS=''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_AU
  locale-coding-system: iso-8859-1
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  show-paren-mode: t
  encoded-kbd-mode: t
  file-name-shadow-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  auto-compression-mode: t
  line-number-mode: t


[-- Attachment #2: foo.el --]
[-- Type: application/emacs-lisp, Size: 95 bytes --]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #3: foo.pl --]
[-- Type: text/x-perl, Size: 1353 bytes --]

#!/usr/bin/perl

sleep 2;
$| = 1;

print 'xxxxxxxx: xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxxxx.xx xxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx';
sleep 2;

print ' xxx.xx xxxxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxx.xx xxxxx.xx xxx.xx xxx.xx xxx.xx xxx.xx
';
sleep 2;

foreach (1..100) { print "bar\n"; }
exit 0;

bug#367: compilation-scroll-output not working on certain long line

[Stefan Monnier]

> With foo.el and foo.pl below, running

> 	emacs -Q foo.el
> 	M-x eval-buffer

> produces a compilation window showing only "xxx.xx" bits, where I hoped
> setting compilation-scroll-output to `t' in foo.el would make it follow
> the further output after that, ie. the "bar" lines (which you can see by
> switching to the *compilation* buffer and scrolling down).

> The foo.pl script is merely to print the provoking output.  It's a long
> line arriving as its first 1024 bytes and then enough to just fill the
> 10-line compilation window.  During the second sleep the end of the
> "xxx.xx" is the last line in the window.

> I get the problem on both a console tty and under gtk X, and in both the
> debian packaged 22.2 and my build of the current cvs.  It seems to
> depend on the sleeps, ie. pauses in the output, so if you don't get the
> effect you might try increasing them a bit.

I cannot reproduce it on the current CVS trunk, tho I can reproduce it
on the 22 branch.  I have just installed a change in the way
window-point is handled in compile buffers which may have fixed
your bug.
Can you confirm that your bug is now fixed on the CVS trunk?


        Stefan

bug#367: compilation-scroll-output not working on certain long line

[Kevin Ryde]

Stefan Monnier <monnier@iro.umontreal.ca> writes:
>
> Can you confirm that your bug is now fixed on the CVS trunk?

Alas, still the same, both on the console and in X/Gtk.

bug#367: compilation-scroll-output not working on certain long line

[Stefan Monnier]

>> Can you confirm that your bug is now fixed on the CVS trunk?
> Alas, still the same, both on the console and in X/Gtk.

Yes, this time I was able to reproduce it, but... no patch yet.


        Stefan

bug#367: compilation-scroll-output not working on certain long line

[Andrew Hyatt]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>>> Can you confirm that your bug is now fixed on the CVS trunk?
>> Alas, still the same, both on the console and in X/Gtk.
>
> Yes, this time I was able to reproduce it, but... no patch yet.

I was unable to reproduce in console or with in the Mac GUI with Emacs
25. I wasn't able to try with X/Gtk, but since you also were able to
reproduce with the console, and a lot of time has passed, this probably
has been fixed at some point. I'm going to mark this bug as
unreproducible, please reopen if you still see this as broken on Emacs
25.

>
>
>         Stefan