Re: [PATCH] tests: fix and add lint for non-portable head -c N

[Junio C Hamano <gitster@pobox.com>]

Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:

> Junio: Even though this isn't a 2.19.0-rc0 regression I think it makes
> sense for 2.19.0. The fix is trivial, and it'll unbreak (at least some
> of) the tests on stock git on OpenBSD.

I would have been a bit more sympathetic if this were recent
regression (say, 2.18 or so), even if it is not new in this cycle,
and the patch applied to the target track cleanly (say, maint or
maint-2.17), but seeing that some of these are quite old, dating
back to 2009, I am not sure I am enthused.

The changes certainly look trivial.  Let's apply.

Thanks.

>
> OpenBSD guys: If you CC the git mailing list when you find you need to
> apply patches like these, we're happy to fix this more pro-actively. I
> just happened to be testing the upcoming 2.19.0 on OpenBSD and spotted
> this.
>
>  t/check-non-portable-shell.pl | 1 +
>  t/t5310-pack-bitmaps.sh       | 2 +-
>  t/test-lib.sh                 | 4 ++--
>  3 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/t/check-non-portable-shell.pl b/t/check-non-portable-shell.pl
> index d5823f71d8..94a7e6165e 100755
> --- a/t/check-non-portable-shell.pl
> +++ b/t/check-non-portable-shell.pl
> @@ -35,6 +35,7 @@ sub err {
>  		chomp;
>  	}
>  
> +	/\bhead\s+-c\b/ and err 'head -c is not portable (use test_copy_bytes BYTES <file >out)';
>  	/\bsed\s+-i/ and err 'sed -i is not portable';
>  	/\becho\s+-[neE]/ and err 'echo with option is not portable (use printf)';
>  	/^\s*declare\s+/ and err 'arrays/declare not portable';
> diff --git a/t/t5310-pack-bitmaps.sh b/t/t5310-pack-bitmaps.sh
> index 557bd0d0c0..7bff7923f2 100755
> --- a/t/t5310-pack-bitmaps.sh
> +++ b/t/t5310-pack-bitmaps.sh
> @@ -335,7 +335,7 @@ test_expect_success 'truncated bitmap fails gracefully' '
>  	git rev-list --use-bitmap-index --count --all >expect &&
>  	bitmap=$(ls .git/objects/pack/*.bitmap) &&
>  	test_when_finished "rm -f $bitmap" &&
> -	head -c 512 <$bitmap >$bitmap.tmp &&
> +	test_copy_bytes 512 <$bitmap >$bitmap.tmp &&
>  	mv -f $bitmap.tmp $bitmap &&
>  	git rev-list --use-bitmap-index --count --all >actual 2>stderr &&
>  	test_cmp expect actual &&
> diff --git a/t/test-lib.sh b/t/test-lib.sh
> index 8bb0f4348e..44288cbb59 100644
> --- a/t/test-lib.sh
> +++ b/t/test-lib.sh
> @@ -867,7 +867,7 @@ then
>  		# handle only executables, unless they are shell libraries that
>  		# need to be in the exec-path.
>  		test -x "$1" ||
> -		test "# " = "$(head -c 2 <"$1")" ||
> +		test "# " = "$(test_copy_bytes 2 <"$1")" ||
>  		return;
>  
>  		base=$(basename "$1")
> @@ -882,7 +882,7 @@ then
>  		# do not override scripts
>  		if test -x "$symlink_target" &&
>  		    test ! -d "$symlink_target" &&
> -		    test "#!" != "$(head -c 2 < "$symlink_target")"
> +		    test "#!" != "$(test_copy_bytes 2 <"$symlink_target")"
>  		then
>  			symlink_target=../valgrind.sh
>  		fi