bug#2282: Bug#2282: rmail-summary splits frame into three parts

[martin rudalics <rudalics@gmx.at>]

 > I'm tempted to just replace all pop-to-buffers in rmail*.el with
 >
 > (defun rmail-pop-to-buffer (buffer-or-name &optional other-window norecord)
 >   (let (split-width-threshold)
 >     (pop-to-buffer buffer-or-name other-window norecord)))

I suppose the following code in `rmail-new-summary' is responsible for
the behavior described earlier.

       (if (and (one-window-p)
	       pop-up-windows
	       (not pop-up-frames))
	  ;; If there is just one window, put the summary on the top.
	  (progn
	    (split-window (selected-window) rmail-summary-window-size)
	    (select-window (next-window (frame-first-window)))
	    (pop-to-buffer rmail-summary-buffer)
	    ;; If pop-to-buffer did not use that window, delete that
	    ;; window.  (This can happen if it uses another frame.)
	    (if (not (eq rmail-summary-buffer
			 (window-buffer (frame-first-window))))
		(delete-other-windows)))
	(pop-to-buffer rmail-summary-buffer))

What is that code supposed to do what a simple `pop-to-buffer' cannot
accomplish?  If it's to display the summary on top of the frame, then
splitting horizontally obviously won't make sense here.

martin