bug#2350: 23.0.90; compilation-mode inserts output in the wrong location

[Eric Hanchrow <erich@cozi.com>]

Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

Your bug report will be posted to the emacs-pretest-bug@gnu.org mailing list.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

I started a long-running "compilation" that simply emmitted the time every two seconds:

        M-x compile RET C-a C-k while sleep 2; do date; done RET

I then narrowed the *compilation* buffer to the first few lines:

        C-@ C-u C-n C-u C-n C-x n n

I then sat and watched as the current date got inserted at the end of my
narrowed region.  I'd expected it to be inserted instead at the end of
the buffer, even though that happened to be invisible.

This is arguably not a bug, but the behavior I'd expected is indeed
useful: sometimes when a compilation is running, I want to study just
part of the output, and it's convenient to narrow to just the part I
want.  With the current behavior, though, in order to avoid getting the
*compilation* buffer's lines all mixed up, I must copy the interesting
region to another buffer.

In GNU Emacs 23.0.90.1 (i686-pc-linux-gnu, GTK+ Version 2.12.9)
 of 2009-02-04 on ubuntu-erich
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: nil
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default-enable-multibyte-characters: t

Major mode: Compilation

Minor modes in effect:
  erc-ring-mode: t
  erc-pcomplete-mode: t
  erc-netsplit-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-autojoin-mode: t
  erc-track-mode: t
  erc-match-mode: t
  erc-services-mode: t
  erc-networks-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-readonly-mode: t
  desktop-save-mode: t
  display-time-mode: t
  global-auto-revert-mode: t
  diff-auto-refine-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-e RET ESC p C-b C-b C-b C-b C-b \ n C-f C-f \ n C-e 
RET C-u C-p C-@ ESC C-n ESC w C-x o C-n ESC m ESC C-o 
C-y , C-p C-a C-k C-x C-o C-x C-s C-p ESC m ESC . C-n 
C-n C-n ESC C-f ESC f ESC . C-x o ESC > q ( ) . RET 
C-x k RET ESC x m a k e RET y e s RET C-x o C-u C-@ 
C-x 0 ESC > C-x [ ESC > C-h v C-x [ C-g C-h v C-x [ 
C-g C-g C-h c C-x [ C-x [ C-x ] C-u C-x $ C-x [ C-x 
$ C-x [ C-x ] C-n ESC 0 C-l C-x ] C-p C-x n p ESC < 
C-x 2 C-x o C-v C-u C-x $ C-x 0 C-s n o t SPC t C-n 
C-a C-p C-x $ C-u C-x $ C-n C-n C-n C-n C-n C-n C-n 
C-n C-s k i C-w C-r C-r C-r C-s C-s C-s C-s C-s C-s 
C-s C-s C-s C-a C-u C-@ C-x n p ESC < C-v C-x n w C-x 
n p C-x n w C-c C-k ESC > C-c C-k ESC x w o m a n RET 
y e s RET q ESC x c o m p i l e RET C-a C-k w h i l 
e SPC s l e e p SPC 2 ; SPC d o SPC e c h o SPC ESC 
DEL d a t e ; SPC d o n e RET C-@ C-u C-n C-u C-n C-p 
C-x n n C-x n w ESC > C-g C-c C-k ESC x r e p o r t 
- TAB m e TAB DEL DEL e m TAB RET

Recent messages:
Mark saved where search started
Mark set [2 times]
Compilation interrupt
uncompressing yes.1.gz...done
WoMan formatting buffer...done in 0 seconds
(No files need saving)
Mark activated
Quit
Compilation interrupt
Making completion list...