Re: [PATCH] p3400: stop using tac(1)

From: Junio C Hamano <gitster@pobox.com>
Date: Oct 7, 2021, 23:44 UTC
Message-ID: <xmqqzgrkmmd7.fsf@gitster.g>
In-Reply-To: <a3377973-4f4a-376a-f02e-94a3b20dd9ad@web.de>

René Scharfe <l.s.r@web.de> writes:

> In my mind, test is an external command.  Wikipedia [1] says it has been
> a builtin since the early 80ies, and I couldn't find a shell without it.
> I wonder where I picked up that outdated assumption -- I'm not actually
> _that_ old.  Time for an update..

Funny, as I was wondering about the same thing the other day in a totally different context.

Our older shell script (like tests) tends to strongly prefer "case ... esac" over "test" for this exact reason, e.g option parsing loop often uses

    while case $#,$1 in 0,*) break ;; *,-*) ;; *) break ;; esac
    do
	...

instead of

    while test $# -gt 0 && ...

to avoid "test". I'm not actually _that_ old, either, but my current suspicion is that those who traind us are old enough ;-)