bug#1415: 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument

bug#1415: 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument

[Helmut Eller]

I think that display-buffer returns sometimes the selected window even
if the NOT-THIS-WINDOW argument is true.  Here is a test case:

(progn
  (defun display-buffer-checked (buffer)
    (let ((selected (selected-window))
          (window (display-buffer buffer t)))
      (when (eq selected window)
        (error "display-buffer returned selected window"))
      window))
  
  (let ((foo (get-buffer-create "foo"))
        (bar (get-buffer-create "bar")))
    (select-window (get-buffer-window "*scratch*"))
    (save-selected-window 
      (select-window (display-buffer-checked foo)))
    (save-selected-window 
      (select-window (display-buffer-checked bar)))))


display-buffer-checked just calls display-buffer and checks that the
returned window isn't the selected window.  From looking at the code of
display-buffer, I would say that display-buffer returns the lru window
even if that's the selected window.

Helmut.


In GNU Emacs 23.0.60.10 (i686-pc-linux-gnu, GTK+ Version 2.8.20)
 of 2008-11-22 on xaital
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--without-sound' '--without-pop' '--without-gif' '--without-tiff''

bug#1415: 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument

[martin rudalics]

[-- Attachment #1: Type: text/plain, Size: 1142 bytes --]

 > I think that display-buffer returns sometimes the selected window even
 > if the NOT-THIS-WINDOW argument is true.  Here is a test case:
 >
 > (progn
 >   (defun display-buffer-checked (buffer)
 >     (let ((selected (selected-window))
 >           (window (display-buffer buffer t)))
 >       (when (eq selected window)
 >         (error "display-buffer returned selected window"))
 >       window))
 >
 >   (let ((foo (get-buffer-create "foo"))
 >         (bar (get-buffer-create "bar")))
 >     (select-window (get-buffer-window "*scratch*"))
 >     (save-selected-window
 >       (select-window (display-buffer-checked foo)))
 >     (save-selected-window
 >       (select-window (display-buffer-checked bar)))))
 >
 >
 > display-buffer-checked just calls display-buffer and checks that the
 > returned window isn't the selected window.  From looking at the code of
 > display-buffer, I would say that display-buffer returns the lru window
 > even if that's the selected window.

Nice bug.  Thanks for the precise report and test case!

Emacs 22 handled this, but I'm too lazy to figure out how.

Please try the attached patch.

martin

[-- Attachment #2: window.diff --]
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*** window.el.~1.168.~	2008-11-18 22:26:34.390625000 +0100
--- window.el	2008-11-24 10:31:29.953125000 +0100
***************
*** 1038,1051 ****
  		     (window--try-to-split-window
  		      (get-lru-window frame-to-use t))))
  	   (window--display-buffer-2 buffer window-to-use)))
!      ((setq window-to-use
! 	    ;; Reuse an existing window.
! 	    (or (get-lru-window frame-to-use)
! 		(get-buffer-window buffer 'visible)
! 		(get-largest-window 'visible nil)
! 		(get-buffer-window buffer 0)
! 		(get-largest-window 0 nil)
! 		(frame-selected-window (funcall pop-up-frame-function))))
        (window--even-window-heights window-to-use)
        (window--display-buffer-2 buffer window-to-use)))))
  
--- 1038,1063 ----
  		     (window--try-to-split-window
  		      (get-lru-window frame-to-use t))))
  	   (window--display-buffer-2 buffer window-to-use)))
!      ((let ((window-to-undedicate
! 	     ;; When NOT-THIS-WINDOW is non-nil, temporarily dedicate
! 	     ;; the selected window to its buffer, to avoid that some of
! 	     ;; the routines below choose it.  (Bug#1415)
! 	     (and not-this-window
! 		  (not (window-dedicated-p (selected-window)))
! 		  (set-window-dedicated-p (selected-window) t)
! 		  (selected-window))))
! 	(unwind-protect
! 	    (setq window-to-use
! 		  ;; Reuse an existing window.
! 		  (or (get-lru-window frame-to-use)
! 		      (get-buffer-window buffer 'visible)
! 		      (get-largest-window 'visible)
! 		      (get-buffer-window buffer 0)
! 		      (get-largest-window 0)
! 		      (frame-selected-window (funcall pop-up-frame-function))))
! 	  (when (window-live-p window-to-undedicate)
! 	    ;; Restore dedicated status of selected window.
! 	    (set-window-dedicated-p window-to-undedicate nil))))
        (window--even-window-heights window-to-use)
        (window--display-buffer-2 buffer window-to-use)))))
  

bug#1415: 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument

[Helmut Eller]

* martin rudalics [2008-11-24 10:59+0100] writes:

>
> Nice bug.  Thanks for the precise report and test case!
>
> Emacs 22 handled this, but I'm too lazy to figure out how.
>
> Please try the attached patch.

I've used the patch now for two days and it seems to work well.

Thank you for the quick fix.

Helmut.

bug#1415: marked as done (23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument)

[Emacs bug Tracking System]

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Your message dated Thu, 27 Nov 2008 14:41:11 +0100
with message-id <492EA377.40504@gmx.at>
and subject line Re: bug#1415: 23.0.60;	display-buffer doesn't honor NOT-THIS-WINDOW argument
has caused the Emacs bug report #1415,
regarding 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

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-- 
1415: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=1415
Emacs Bug Tracking System
Contact don@donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 2979 bytes --]

From: Helmut Eller <eller.helmut@gmail.com>
To: emacs-pretest-bug@gnu.org
Subject: 23.0.60; display-buffer doesn't honor NOT-THIS-WINDOW argument
Date: Sat, 22 Nov 2008 18:01:37 +0100
Message-ID: <m24p1zofta.fsf@gmail.com>


I think that display-buffer returns sometimes the selected window even
if the NOT-THIS-WINDOW argument is true.  Here is a test case:

(progn
  (defun display-buffer-checked (buffer)
    (let ((selected (selected-window))
          (window (display-buffer buffer t)))
      (when (eq selected window)
        (error "display-buffer returned selected window"))
      window))
  
  (let ((foo (get-buffer-create "foo"))
        (bar (get-buffer-create "bar")))
    (select-window (get-buffer-window "*scratch*"))
    (save-selected-window 
      (select-window (display-buffer-checked foo)))
    (save-selected-window 
      (select-window (display-buffer-checked bar)))))


display-buffer-checked just calls display-buffer and checks that the
returned window isn't the selected window.  From looking at the code of
display-buffer, I would say that display-buffer returns the lru window
even if that's the selected window.

Helmut.


In GNU Emacs 23.0.60.10 (i686-pc-linux-gnu, GTK+ Version 2.8.20)
 of 2008-11-22 on xaital
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--without-sound' '--without-pop' '--without-gif' '--without-tiff''



[-- Attachment #3: Type: message/rfc822, Size: 1708 bytes --]

From: martin rudalics <rudalics@gmx.at>
To: 1415-done@emacsbugs.donarmstrong.com
Cc: Helmut Eller <eller.helmut@gmail.com>
Subject: Re: bug#1415: 23.0.60;	display-buffer doesn't honor NOT-THIS-WINDOW argument
Date: Thu, 27 Nov 2008 14:41:11 +0100
Message-ID: <492EA377.40504@gmx.at>

> I've used the patch now for two days and it seems to work well.

I've checked in a slightly more restrictive version.
Please try again and keep an eye on this.

Thanks again for reporting, martin.