Carbon: display-buffer can leave wrong frame with input focus

[David Reitter]

The below issue is reproducible in a plain GNU Emacs (Carbon). Note  
that the X11 version is reported to work fine, but not Carbon Emacs.
This might not be considered a bug by some of you (for example  
because the window manager selects the new frame), but I still think  
synchronizing the behavior of the X11 version and the Carbon  
implementation could be advantageous.


Begin forwarded message:

> From: Mark Russell <address@hidden>
> Date: 9 December 2005 18:48:52 GMT
> To: address@hidden
> Subject: [Aquamacs-bugs] display-buffer can leave wrong frame with  
> input focus
>
> display-buffer leaves the wrong frame selected in the following  
> situation:
>
>     - You have a frame selected
>
>     - You call display-buffer on a buffer which is listed in  
> special-display-buffer-names
>       (and not displayed in the frame you currently have selected)
>
> This creates a new frame to display the buffer (if it is not  
> displayed already)
> and leaves that frame selected.  Any subsequent input goes to the  
> buffer in that frame, but the documentation for display-buffer says  
> that it does not select the buffer.
>
> To reproduce the bug, load the following code:
>
>     (setq special-display-buffer-names '("*test-buffer*"))
>
>     (defun test-display-buffer ()
>       "Test frame focus by visiting a buffer in an unsplittable  
> window"
>       (interactive)
>       (display-buffer (get-buffer-create "*test-buffer*")))
>
> In one frame say M-x test-display-buffer.  A new frame will appear  
> displaying *test-buffer* and the input focus will be left there.   
> This also happens in Carbon emacs, but under X11 emacs the new  
> frame is created, but the input focus remains in the original  
> frame, which I believe is the correct behavior).
>
> I tripped over this using the compile library, where the call of  
> display-buffer in compilation-goto-locus causes the input focus to  
> alternate between the compilation error messages window and the  
> source file window each time you use next-error (I have  
> "*compilation*" listed in special-display-buffer-names).  This  
> makes stepping through a stack trace almost unusable for me.  As a  
> workaround I replaced the display-buffer call in compilation-goto- 
> locus with get-buffer-window, but I think the display-buffer  
> behavior is the actual bug.
>
> Mark Russell
>
> In GNU Emacs 22.0.50.1 (powerpc-apple-darwin7.9.0)
>  of 2005-12-02 on rodrigues.inf.ed.ac.uk - Aquamacs Distribution 0.9.7
> Distributor `Apple Computers', version 10.4.3
> configured using `configure '--without-x' '--prefix=/usr/local''
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