bug#16533: 24.3.50; "s" no longer works as documented in dired

[Glenn Morris <rgm@gnu.org>]

Eli Zaretskii wrote:

> The problem here seems to be that dired-sort-toggle blindly adds the
> "-t" flag to dired-actual-switches, although in this case the sorting
> is not by date at all.  I don't understand the logic here; it seems
> like dired-sort-toggle assumes without testing that the directory is
> sorted either by date or by name, which is of course false.
>
> Is it a portable assumption that the last switch that determines the
> sorting order overrides all the previous ones?  If so, ls-lisp.el
> should be fixed to implement that requirement.  But if not, we need to
> fix dired.el not to put more than one sorting option into
> dired-actual-switches.  In particular, the logic in dired-sort-toggle
> seems to be flawed.

Duh, I seem to have been very thick here, since the original report
seems clear now. I guess I missed the 'then press "s"'.

I guess it is not a portable assumption, since presumably whatever
crappy ls Mac OS X uses does not work that way.

Prior to r101356, dired-sort-toggle removed dired-ls-sorting-switches.
Now it seems not to. That change was made to fix another bug,
http://debbugs.gnu.org/6987