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From: Junio C Hamano <gitster@pobox.com>
To: Han-Wen Nienhuys <hanwen@google.com>
Cc: Patrick Steinhardt <ps@pks.im>,  git@vger.kernel.org
Subject: Re: [PATCH 00/11] t: reduce direct disk access to data structures
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	(Han-Wen Nienhuys's message of "Thu, 19 Oct 2023 12:13:12 +0200")
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Date: Thu, 19 Oct 2023 10:55:08 -0700
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 A542318A-6EA8-11EE-A972-78DCEB2EC81B-77302942!pb-smtp1.pobox.com

Han-Wen Nienhuys <hanwen@google.com> writes:

> I think it would be really great if there were separate unittests for
> the ref backend API. Some of the reftable work was needlessly
> difficult because the contract of the API was underspecified. The API
> is well compartmentalized in refs-internal.h, and a lot of the API
> behavior can be tested as a black box, eg.
>
> * setup symref HEAD pointing to R1
> * setup transaction updating ref R1 from C1 to C2
> * commit transaction, check that it succeeds
> * read ref R1, check if it is C2
> * read reflog for R1, see that it has a C1 => C2 update
> * read reflog for HEAD, see that it has a C1 => C2 update
>
> Tests for the loose/packed backend could directly mess with the
> on-disk files to test failure scenarios.
>
> With unittests like that, the tests can zoom in on the functionality
> of the ref backend, and provide more convenient coverage for
> dynamic/static analysis.

Yeah, I agree that something like that would really be great.