Subject: Re: [GSoC] [PATCH v2 1/3] t9811: avoid using pipes to expose exit codes

From: Junio C Hamano <[email-masked]>
Date: Mon, 07 Apr 2025 17:19:57 +0000

Anthony Wang <[email-masked]> writes:

> The exit code of the upstream in a pipe is suppressed
> thus we lose any exit codes of git commands that are piped. In order to
> ensure we pick up the exit code, we can write the output of the git command
> to a file, testing the exit codes of both the commands.

Sort of correct, but ...

> ---
>  t/t9811-git-p4-label-import.sh | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)

Missing sign-off.

> diff --git a/t/t9811-git-p4-label-import.sh b/t/t9811-git-p4-label-import.sh
> index 5ac5383fb7..5abac938d0 100755
> --- a/t/t9811-git-p4-label-import.sh
> +++ b/t/t9811-git-p4-label-import.sh
> @@ -95,9 +95,10 @@ test_expect_success 'two labels on the same changelist' '
>  		cd "$git" &&
>  		git p4 sync --import-labels &&
>  
> -		git tag | grep TAG_F1 &&
> -		git tag | grep -q TAG_F1_1 &&
> -		git tag | grep -q TAG_F1_2 &&
> +		git tag >output &&
> +		grep TAG_F1 output &&
> +		grep -q TAG_F1_1 output &&
> +		grep -q TAG_F1_2 output &&

Think what these tests are trying to do.  After a "git p4 sync"
operation, they want to ensure that tags TAG_F1_1 and TAG_F1_2
exist?  Does the test want to see a tag "TAG_F1", or is it only that
the test is written in a so sloppy way that grepping for TAG_F1 will
be happy when any one of TAG_F1_1, TAG_F1_2 and TAG_F1_ONLY exists,
making its purpose of verifying that the tags are in the expected
state pretty much useless, and that is the reason why it needs to be
followed up with the two extra tests?

What is the desired state you want to ensure after "git p4 sync"
operation above?  I do not do "git p4", but you may know better than
I do, as you are the one who is patching this test file ;-)  I am
guessing that you want TAG_F1_1 and TAG_F1_2 to exist and you do not
want TAG_F1_ONLY to exist?

If so, instead of grepping around, we should be testing that in a
more direct way, perhaps with something like

	git show-ref --verify refs/tags/TAG_F1_1 &&
	git show-ref --verify refs/tags/TAG_F1_2 &&
	test_must_fail 	git show-ref --verify refs/tags/TAG_F1_ONLY &&

no?

>  		cd main &&
>  
> @@ -208,7 +209,8 @@ test_expect_success 'use git config to enable import/export of tags' '
>  		git p4 rebase --verbose &&
>  		git p4 submit --verbose &&
>  		git tag &&
> -		git tag | grep TAG_F1_1
> +		git tag >output &&
> +		grep TAG_F1_1 output
>  	) &&
>  	(
>  		cd "$cli" &&