From: Jonathan Nieder <jrnieder@gmail.com>
Date: Mon, 13 Oct 2014 16:10:22 GMT
Subject: Re: [PATCH 2/3] t5304: use helper to report failure of "test foo = bar"
Message-ID: <20141013161022.GA20520@google.com>
In-Reply-To: <20141010061114.GB15277@peff.net>

Jeff King wrote:

> For small outputs, we sometimes use:
>
>   test "$(some_cmd)" = "something we expect"
>
> instead of a full test_cmp. The downside of this is that
> when it fails, there is no output at all from the script.

There's another downside to that construct: it loses the exit
status from some_cmd.

[...]
> --- a/t/t5304-prune.sh
> +++ b/t/t5304-prune.sh
> @@ -13,7 +13,7 @@ add_blob() {
>  	before=$(git count-objects | sed "s/ .*//") &&
>  	BLOB=$(echo aleph_0 | git hash-object -w --stdin) &&
>  	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
> -	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
> +	verbose test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&

So ideally this would be something like:

	git count-objects >output &&
	verbose test "$((1 + $before))" = "$(sed "s/ .*//" output)" &&

[...]
> @@ -45,11 +45,11 @@ test_expect_success 'prune --expire' '
>  
>  	add_blob &&
>  	git prune --expire=1.hour.ago &&
> -	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
> +	verbose test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&

and likewise elsewhere in the file.

Alternatively, maybe there could be a helper in the same spirit as
test_cmp_rev?

	test_object_count () {
		git count-objects >output &&
		sed "s/ .*//" output >count &&
		printf "%s\n" "$1" >expect &&
		test_cmp expect count
	}

My two cents,
Jonathan