bug#222: isearch-repeat-forward: wrong overlay after failure

[David Reitter <david.reitter@gmail.com>]

isearch wrongly highlights a part of a buffer when `isearch-forward'  
fails.

To reproduce, create buffer A, containing just the following:

123456

Also, create buffer B, containing

12346

Now switch to buffer A, move point to the beginning, and do C-s 5.   
The `5' will be highlighted.
Then switch to buffer B and move point to the beginning.  (You can  
show the buffers in two windows, or just switch between them: it  
doesn't matter.)
Then do M-x isearch-repeat-forward.  (Do NOT do C-s C-s.)

You will find that `6' is highlighted, and a (correct) message is  
displayed that the search failed.  (It appears that the text at a  
position equivalent to where the last match was in the previous buffer  
is highlighted.)

The overlay in buffer B shouldn't be there.

This issue has been around for a long time, and I suspect it was never  
noticed because many people just do C-s C-s rather than binding a key  
to `isearch-repeat-forward'.






In GNU Emacs 22.2.50.2 (i386-apple-darwin9.2.2, Carbon Version 1.6.0)
  of 2008-04-26 on plume.sr.unh.edu
Windowing system distributor `Apple Inc.', version 10.5.2
configured using `configure  '--without-x' '--prefix=/usr/local''

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
   locale-coding-system: iso-8859-1
   default-enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
   tooltip-mode: t
   tool-bar-mode: t
   mouse-wheel-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   unify-8859-on-encoding-mode: t
   utf-translate-cjk-mode: t
   auto-compression-mode: t
   line-number-mode: t

Recent input:
C-x b <return> <up> <up> <up> <up> <up> C-k C-k C-k
C-k C-k C-k 1 <return> 2 <return> 3 <return> 4 <return>
5 <return> 6 5 <return> <backspace> <backspace> <return>
<escape> x v i s i t - n e <tab> <backspace> <backspace>
<backspace> <backspace> <backspace> <backspace> <backspace>
<backspace> c r e a t e - b <tab> u <backspace> <backspace>
<backspace> <backspace> <backspace> <backspace> <backspace>
<backspace> <backspace> <backspace> v i s i <tab> C-x
C-f T e m p SPC t 1 <backspace> <backspace> <backspace>
/ t 2 <return> 1 <return> 2 <return> 3 <return> 4 <return>
6 <return> <up> <up> <up> <up> <up> <up> <up> <up>
<up> <up> C-x b <return> <up> <up> <up> <up> <up> <up>
<up> <up> <up> <up> <up> <up> <up> C-s 5 C-x b <return>
<escape> x i s e a r c h - r e <tab> <tab> p e <tab>
f o r <tab> <return> <menu-bar> <help-menu> <send-
emacs-bug-report>

Recent messages:
Making completion list...
Loading help-mode...done
Quit
(New file)
Mark saved where search started
Making completion list...
Loading emacsbug...
Loading regexp-opt...done
Loading emacsbug...done
byte-code: Text is read-only [2 times]