Re: [PATCH] t0300-credentials: Word around a solaris /bin/sh bug

From: Junio C Hamano <gitster@pobox.com>
Date: Feb 3, 2012, 21:50 UTC
Message-ID: <7vr4ybmvrq.fsf@alter.siamese.dyndns.org>
In-Reply-To: <20120203212604.GA1890@sigill.intra.peff.net>

Jeff King <peff@peff.net> writes:

Show 15 quoted lines

>> without requiring the brain-cycle to waste on the "Is this simple enough
>> for even Solaris to grok?" guess game.  This should also be reusable for
>> other stuff like $PERL_PATH, I would think.
>
> I like it. Even better would be:
>
>   write_script() {
>         echo "#!$2" >"$1" &&
>         cat >>"$1" &&
>         chmod +x "$1"
>   }
>
>   write_script foo.sh "$SHELL_PATH" <<-\EOF
>     echo my arguments are "$@"
>   EOF

I first thought that the order of parameters were unusual, but with that order, you could even go something fancier like:

	write_script () {
		case "$#" in
		1)	case "$1" in
			*.perl | *.pl) echo "#!$PERL_PATH" ;;
			*) echo "#!$SHELL_PATH" ;;
			esac
                2)	echo "#!$2" ;;
		*)	BUG ;;
                esac >"$1" &&
                cat >>"$1" &&
                chmod +x "$1"
	}

	write_script foo.sh
        write_script bar.perl
        write_script pre-receive /no/frobnication/today

The tongue-in-cheek comment aside, I think ${2-"$SHELL_PATH"} or some form of fallback would be a good idea in any case, as 99% of the time what we write in the test scripts is a shell script.

Also "chmod +x" is a very good idea.