Re: [PATCH v2 02/11] cache-tree tests: use a sub-shell with less indirection

From: Jeff King <peff@peff.net>
Date: Jan 17, 2021, 16:55 UTC
Message-ID: <YARsCsgXuiXr4uFX@coredump.intra.peff.net>
In-Reply-To: <20210116153554.12604-3-avarab@gmail.com>

On Sat, Jan 16, 2021 at 04:35:45PM +0100, Ævar Arnfjörð Bjarmason wrote:

Show 16 quoted lines

> diff --git a/t/t0090-cache-tree.sh b/t/t0090-cache-tree.sh
> index 354b7f15f7..2e3efeb80e 100755
> --- a/t/t0090-cache-tree.sh
> +++ b/t/t0090-cache-tree.sh
> @@ -27,20 +27,15 @@ generate_expected_cache_tree_rec () {
>  	printf "SHA $dir (%d entries, %d subtrees)\n" "$entries" "$subtree_count" &&
>  	for subtree in $subtrees
>  	do
> -		cd "$subtree"
> -		generate_expected_cache_tree_rec "$dir$subtree" || return 1
> -		cd ..
> +		(
> +			cd "$subtree"
> +			generate_expected_cache_tree_rec "$dir$subtree" || return 1
> +		)
>  	done

We don't check that "cd" worked either before or after your patch. Should we?

After your patch, we "return" from inside a subshell. Is that portable? ISTR issues around that before, but it just have been when we are not in a function at all. Still, I wonder if:

  for ...
  do
	(
		cd "$subtree" &&
		generate_expected_cache_tree_rec "$dir$subtree"
	) || return 1
  done

might be more obvious.

Show 5 quoted lines

> -generate_expected_cache_tree () {
> -	(
> -		generate_expected_cache_tree_rec
> -	)
> -}

I wondered what the "rec" was for, but I guess it is "recurse". Not a problem to keep it, but I wonder if it could be dropped in the name of shortness/simplicity (not worth a re-roll for sure, but maybe worth doing so if you re-roll for the above issues).

-Peff