From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH 1/3] t3404: preserve test_tick state across short SHA-1
 collision test
Date: Sat, 24 Aug 2013 22:55:50 -0700
Message-ID: <20130825055550.GN2882@elie.Belkin>
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Cc: git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>
To: Eric Sunshine <sunshine@sunshineco.com>
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Hi,

Eric Sunshine wrote:

> The short SHA-1 collision test requires carefully crafted commits in
> order to ensure a collision at rebase time.

Yeah, this breaks the usual rule that tests should be independent
of hashing function.  But it's the best we can do, I think.

[...]
> --- a/t/t3404-rebase-interactive.sh
> +++ b/t/t3404-rebase-interactive.sh
> @@ -994,17 +994,23 @@ test_expect_success 'short SHA-1 setup' '
>  	test_when_finished "git checkout master" &&
>  	git checkout --orphan collide &&
>  	git rm -rf . &&
> +	(
>  	unset test_tick &&
>  	test_commit collide1 collide &&
>  	test_commit --notick collide2 collide &&
>  	test_commit --notick "collide3 115158b5" collide collide3 collide3
> +	)

Would be clearer if the code in a subshell were indented:

	(
		unset test_tick &&
		test_commit ...
	)

[...]
>  test_expect_success 'short SHA-1 collide' '
>  	test_when_finished "reset_rebase && git checkout master" &&
>  	git checkout collide &&
> +	(
> +	unset test_tick &&
> +	test_tick &&
>  	FAKE_COMMIT_MESSAGE="collide2 815200e" \
>  	FAKE_LINES="reword 1 2" git rebase -i HEAD~2
> +	)

Likewise.

Hope that helps,
Jonathan