Subject: Re: [PATCH v2 2/2] t6300: check for cat-file exit status code

From: Junio C Hamano <[email-masked]>
Date: Thu, 19 Aug 2021 13:19:42 -0700

Đoàn Trần Công Danh  <[email-masked]> writes:

> In test_atom(), we're piping the output of cat-file to tail(1),
> thus, losing its exit status.
>
> Let's use a temporary file to preserve git exit status code.
>
> Signed-off-by: Đoàn Trần Công Danh <[email-masked]>
> ---
>  t/t6300-for-each-ref.sh | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
> index 93126341b3..cc0f5b6627 100755
> --- a/t/t6300-for-each-ref.sh
> +++ b/t/t6300-for-each-ref.sh
> @@ -66,7 +66,9 @@ test_atom() {
>  			case $type in
>  			tag)
>  				# We cannot use $3 as it expects sanitize_pgp to run
> -				expect=$(git cat-file tag $ref | tail -n +6 | wc -c) ;;
> +				git cat-file tag $ref >out &&
> +				expect=$(tail -n +6 <out | wc -c) &&

It is not wrong per-se, but do we need a redirect '<' here?  "tail"
takes filename(s) on the command line, but is there a reason to feed
the contents from the standard input?

> +				rm -f out ;;
>  			tree | blob)
>  				expect="" ;;
>  			commit)