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From: kjones@talos.uu.net (Kyle Jones)
Newsgroups: gnu.emacs.bug
Subject: Re: Suspected bug in set-window-point
Message-ID: <1990Jan23.133024.29492@talos.uu.net>
Date: 23 Jan 90 13:30:24 GMT
References: <9001230152.AA02410@tarski.mit.edu>
Reply-To: kjones@talos.uu.net
Lines: 38

drw@BOURBAKI.MIT.EDU writes about:
 > I believe there is a bug in the code for set-window-point.  [...]
 > The apparent cause is that the code of set-window-point is:
 > 
 > 	if WINDOW == selected-window()
 > 	then goto-char(POS)
 > 	else set-marker(WINDOW->pointm, POS, WINDOW->buffer)
 > 
 > This appears to omit a check that the current buffer is the buffer of
 > WINDOW, as is done in window-point:
 > 
 > 	if WINDOW == selected-window() && current-buffer() == WINDOW->buffer
 > 	then return point()
 > 	else return marker-position(WINDOW->pointm)

Correct.  I reported this bug and received this new definition of
Fset_window_point from RMS to test; it fixes the problem.  Since it
hasn't made it into the distribution yet, here it is.

DEFUN ("set-window-point", Fset_window_point, Sset_window_point, 2, 2, 0,
  "Make point value in WINDOW be at position POS in WINDOW's buffer.")
  (window, pos)
     Lisp_Object window, pos;
{
  register struct window *w = decode_window (window);

  CHECK_NUMBER_COERCE_MARKER (pos, 1);
  if (w == XWINDOW (selected_window))
    {
      struct buffer *obuf = bf_cur;
      Fset_buffer (w->buffer);
      Fgoto_char (pos);
      SetBfp (obuf);
    }
  else
    Fset_marker (w->pointm, pos, w->buffer);
  return pos;
}