Problems with non-zero scroll-margin

[Ralf Angeli]

As far as I can see the changset

2005-06-25  Richard M. Stallman  <address@hidden>

        * macfns.c (Fx_show_tip): Pass new arg to try_window.

        * w32fns.c (Fx_show_tip): Pass new arg to try_window.

        * xfns.c (Fx_show_tip): Pass new arg to try_window.

        * xdisp.c (try_window): New arg CHECK_MARGINS.  Calls changed.
        (redisplay_window): Handle try_window reporting point in scroll margin.

        * dispextern.h (try_window): Declare new arg.

at least broke scrolling of articles with <RET> in Gnus and makes
using GDB in Emacs (gud-mode) very inconvenient if the value of
`scroll-margin' is non-zero.  In case of Gnus the article won't be
scrolled and point will end up in the middle of the window.  In case
of GDB typing <RET> e.g. for stepping through a function will make
point end up in the middle of the window as well, which means you have
to move it manually to the prompt again.

Here is a test case which mimics the behavior of Gnus:

(progn
  (setq scroll-margin 1)
  (pop-to-buffer (get-buffer-create "*test*"))
  (dotimes (i 100) (insert (number-to-string i) "\n"))
  (goto-char (point-min))
  (scroll-up 1)
  (move-to-window-line 0))

You should see that point will not be placed on the first window line
but in the middle of the window.


In GNU Emacs 22.0.50.9 (i686-pc-linux-gnu, GTK+ Version 2.6.8)
 of 2005-07-01 on neutrino
X server distributor `The XFree86 Project, Inc', version 11.0.40300001
configured using `configure '--with-gtk''

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: en_US
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  desktop-save-mode: t
  display-time-mode: t
  iswitchb-mode: t
  show-paren-mode: t
  encoded-kbd-mode: t
  mouse-wheel-mode: t
  auto-compression-mode: t
  menu-bar-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
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  next-error-follow-minor-mode:  Fol

Recent input:
SPC C-e <backspace> <down> <tab> <down> <tab> <down> 
<left> <right> <backspace> <right> <down> <return> 
<up> <up> <up> C-k C-p C-p C-p C-y <down> <down> <down> 
<down> <down> <down> <down> <down> <left> C-x C-e C-x 
k <return> C-x o C-p C-a C-k <down> <left> C-x C-e 
C-x k <return> C-x o C-_ <down> <down> <left> C-x C-e 
C-x k <return> C-x o <down> <down> <right> <up> <up> 
<up> <up> <up> <up> <up> <up> <up> C-SPC <down> <down> 
<down> <down> <down> <down> <down> <down> <down> M-w 
M-x r e p o r t - m e <backspace> <backspace> e m <tab> 
<return>

Recent messages:
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