Dired subdirectories & the ls option time-style with the %R sequence

[Gautier Ponsinet]

Hello everyone,

I use dired with the variable `dired-listing-switches' containing the
--time-style option of ls (from the GNU coreutils), itself containing
the %R sequence. Precisely, I have:

(setq dired-listing-switches "-l -Fhv --group-directories-first 
\"--time-style=+%F %a %R\" ")

in my init.el file.

I have adapted the variable `directory-listing-before-filename-regexp'
accordingly and everything works fine, except when I insert a
subdirectory in dired using `dired-maybe-insert-subdir'. It seems that
the "%R" in the time-style option is interpreted as a -R option in
dired-insert-subdir and is removed (there is a (string-replace "R" ""
switches) somewhere in the function `dired-insert-subdir'). As a result,
the expected time is not printed and only a "%" appears, so my regexp
does not work and dired is confused.

Of course, I can also replace the %R by %H:%M in my config, which I do,
and I don't have this problem. Nevertheless, the bug seems there. It
took me some time to understand the problem, and I guess other people
might encounter the same problem.

Maybe `dired-insert-subdir' could search for "R" but exclude "%R"?

(emacs version: GNU Emacs 28.2 (build 1, x86_64-pc-linux-gnu, GTK+
 Version 3.24.36, cairo version 1.17.6) of 2023-01-03).

All the best,
Gautier