bug#23551: 24.5; beginning-of-line wrong in repeated kbd macro

[Eli Zaretskii <eliz@gnu.org>]

> Date: Mon, 16 May 2016 16:30:32 +0000
> From: abbott@dima.unige.it
> Cc: Abbott John <abbott@dima.unige.it>
> 
> Open the attached file in Emacs, and move point to the first position.
> Define a keyboard macro: (I want to put each line inside double-quotes)
> "			;; self-insert-command
> C-e			;; move-end-of-line
> "			;; self-insert-command
> C-a			;; message-beginning-of-line
> <down>			;; next-line
> 
> Now ask Emacs to repeat this macro 49 times.
> The result is wrong: at around line 35, the first double-quote
> is no longer at the start of the line; then on successive lines
> the position of the first inserted double-quote walks to the right.

Thanks.

This is a duplicate of the (old, but unsolved) bug #13452.  The
problem is not in beginning-of-line, it's in next-line: when the
window needs to scroll as result of next-line, point ends up in
columns 1, 2, 3, ... (i.e. gains one column per line moved down),
instead of sticking to column zero.

To work around, set line-move-visual to nil before running the macro
(or as part of the macro), then the problem goes away.

I'll try to debug this one of these days.