Re: [PATCH 2/2] t0000: avoid masking git exit value through pipes

From: Taylor Blau <me@ttaylorr.com>
Date: Sep 16, 2021, 05:21 UTC
Message-ID: <YULUS3kYkB4RXv2K@nand.local>
In-Reply-To: <20210916023706.55760-3-carenas@gmail.com>

On Wed, Sep 15, 2021 at 07:37:06PM -0700, Carlo Marcelo Arenas Belón wrote:

> 9af0b8dbe2 (t0000-basic: more commit-tree tests., 2006-04-26) adds
> tets for commit-tree that mask the return exit from git as described

s/tets/tests

Show 15 quoted lines

> diff --git a/t/t0000-basic.sh b/t/t0000-basic.sh
> index cb87768513..545ff5af13 100755
> --- a/t/t0000-basic.sh
> +++ b/t/t0000-basic.sh
> @@ -1270,26 +1270,31 @@ test_expect_success 'no diff after checkout and git update-index --refresh' '
>  P=$(test_oid root)
>
>  test_expect_success 'git commit-tree records the correct tree in a commit' '
> -	commit0=$(echo NO | git commit-tree $P) &&
> -	tree=$(git show --pretty=raw $commit0 |
> -		 sed -n -e "s/^tree //p" -e "/^author /q") &&
> +	echo NO | git commit-tree $P >out &&
> +	commit0=$(cat out) &&
> +	git show --pretty=raw $commit0 >out &&
> +	tree=$(cat out | sed -n -e "s/^tree //p" -e "/^author /q") &&

In this and the below tests which had a similar transformation, the first invocation does not mask its error, since it's on the right-hand side of a pipe.

But piping "git show" to sed will mask the exit code of the former. So that makes sense. But I would like to see us avoid an unnecessary cat-into-pipe and instead redirect out into sed, like "sed -n -e ... <out".

Thanks, Taylor