bug#4564: 23.1; Unexpected cursor motion in horizontally scrolled lines

[Eli Zaretskii]

To reproduce:

  emacs -Q
  M-<
  C-x 3
  C-x <
  (answer y to the query whether to enable the command)
  C-x <

Now try C-f and C-b several times and observe the strange effects.
After a while, it becomes apparent that point is actually outside the
visible portion of display, and is being moved by C-f and C-b, but the
cursor stays put in the visible portion and does not show any
movement, except when point enters a different line.

Is that the correct behavior?  Isn't point supposed to be visible at
all times?  If this is the correct behavior, it should at least be
documented.


In GNU Emacs 23.1.3 (x86_64-unknown-linux-gnu, X toolkit)
 of 2009-08-22 on fencepost
configured using `configure  '--with-jpeg=no' '--with-png=no' '--with-gif=no' 
'--with-tiff=no''

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: nil
  value of $XMODIFIERS: nil
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O B ESC O B ESC O A ESC O A C-a C-x < y ESC 
O B ESC O B ESC O B ESC O D ESC O C ESC O A C-e ESC 
O C ESC O A ESC O A ESC O B C-e ESC O A ESC O A ESC 
O D ESC O D ESC O D ESC O D ESC O D ESC O D ESC O D 
ESC O D ESC O D ESC O D ESC O D ESC O D ESC O D ESC 
O D ESC O D ESC O D ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C C-x 1 ESC x r e p o r t - e 
m a c s - TAB RET

Recent messages:
("/home/e/eliz/emacs-23.x/emacs-23.1/src/emacs" "-Q")
For information about GNU Emacs and the GNU system, type C-h C-a.
call-interactively: Text is read-only [2 times]
Quit
Type y, n, ! or SPC (the space bar):