View-quit in *Help* restores wrong window when display-buffer-reuse-frames is t

[David Reitter]

I received the bug report below from an Aquamacs user.

A little investigation traced this to the setting of `display-buffer- 
reuse-frames', which, when t, causes "View-quit" to do the wrong  
thing when restoring the previous window configuration.
In this case, the second window in the frame gets deleted, but the  
first window switches to a different buffer.

The following should reproduce it in a 22 branch CVS Emacs (with  
unrelated patches - I tried Aquamacs with -Q) and also in a 23 one (I  
tried Adrian Robert's Cocoa port):

(progn
  (setq display-buffer-reuse-frames t)
  (describe-mode)
  (other-window 1)
  (View-quit)
)



Begin forwarded message:

> From: Paul Curry <dashteacup@insightbb.com>
> Date: 10 October 2007 05:25:58 BDT
> To: aquamacs-bugs@aquamacs.org
> Subject: [Aquamacs-bugs] View-quit in *Help* restores wrong window
>
> Enter your bug report here.
>
> When I quit from a *Help* buffer (key q, command View-quit) in  
> Aquamacs
> I do not get the correct (or at least expected) behavior.  In other
> Emacsen, if you have two buffers open in a frame -- one of which is a
> *Help* buffer -- and you quit the help buffer, then the frame will  
> fill
> out to only include the other visible buffer.  In Aquamacs, however,
> View-quit fills the frame with a seemingly random unrelated buffer.
>
> For testing purposes I tried the following sequence of commands in
> both Aquamacs and Carbon Emacs:
> Start Emacs
> describe-mode
> other-window
> View-quit
> ---
> In Carbon Emacs I return to the *scratch* buffer, as expected; in
> Aquamacs I change to the *Messages* buffer.  This is reproducible
> every time.
>
> Curious, I checked out the source code for View-quit in both Emacsen
> -- they were the same.  view-mode-exit (called from View-quit) was
> also the same.  The only difference that I can notice is the value of
> view-return-to-alist.  In Carbon Emacs it is:
> ((#<window 8 on *Help*> #<window 3 on *scratch*> . t))
> and in Aqumacs it's:
> ((#<window 7 on *Help*> #<window 3 on *scratch*> . quit-window))
>
> My configuration is:
> Aquamacs 1.2
> OS X 10.4
> not using one-buffer-one-frame-mode
> opening the *Help* buffer in the current frame
>      (http://www.emacswiki.org/cgi-bin/wiki/AquamacsFAQ#toc17)
> hundreds of lines of elisp configuration
>      (I hope this isn't the problem)
>
> In GNU Emacs 22.1.50.1 (i386-apple-darwin8.10.1, Carbon Version 1.6.0)
>   of 2007-10-01 on plume.sr.unh.edu - Aquamacs Distribution 1.2a
> Windowing system distributor `Apple Inc.', version 10.4.10
> 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: Text
>
> Minor modes in effect:
>    flyspell-mode: t
>    auto-insert-mode: t
>    smart-frame-positioning-mode: t
>    aquamacs-styles-mode: t
>    recentf-mode: t
>    encoded-kbd-mode: t
>    show-paren-mode: t
>    delete-selection-mode: t
>    pc-selection-mode: t
>    cua-mode: t
>    auto-image-file-mode: t
>    tooltip-mode: t
>    mac-input-method-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
>    column-number-mode: t
>    line-number-mode: t
>    transient-mark-mode: t
>
> Recent input:
> <down-mouse-1> <mouse-1> C-x C-g <menu-bar> <help-menu>
> <report-emacs-bug> C-x C-f <return> C-n C-n C-n C-n
> C-n C-n C-n C-n C-n C-n C-n C-n C-p C-p <return> M-b
> M-b M-< M-< M-< M-< M-> M-> M-< M-x C-g M-x M-g <menu-bar>
> <help-menu> <report-emacs-bug> C-g C-g <menu-bar> <help-menu>
> <report-emacs-bug>
>
> Recent messages:
> Public License, version 3 or later. Copyright (C) 2007 Free Software
> Foundation,
> Inc. (C) 2007 D. Reitter. No Warranty.
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