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From:   Junio C Hamano <gitster@pobox.com>
To:     "Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com>
Cc:     git@vger.kernel.org, johannes.schindelin@gmx.de, me@ttaylorr.com,
        Jeff Hostetler <git@jeffhostetler.com>,
        Phillip Wood <phillip.wood123@gmail.com>,
        Elijah Newren <newren@gmail.com>,
        Derrick Stolee <derrickstolee@github.com>
Subject: Re: [PATCH v2 6/7] sequencer: implement 'update-refs' command
References: <pull.1247.git.1654263472.gitgitgadget@gmail.com>
        <pull.1247.v2.git.1654634569.gitgitgadget@gmail.com>
        <68f8e51b19c024e1cb075dffd07f81cceaba5957.1654634569.git.gitgitgadget@gmail.com>
Date:   Tue, 07 Jun 2022 15:23:08 -0700
In-Reply-To: <68f8e51b19c024e1cb075dffd07f81cceaba5957.1654634569.git.gitgitgadget@gmail.com>
        (Derrick Stolee via GitGitGadget's message of "Tue, 07 Jun 2022
        20:42:48 +0000")
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"Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Derrick Stolee <derrickstolee@github.com>
>
> The previous change allowed 'git rebase --update-refs' to create 'label'
> commands for each branch  among the commits being rewritten and add an
> 'update-refs' command at the end of the todo list. Now, teach Git to
> update the refs during that final 'update-refs' command.
>
> We need to create an array of new and old OIDs for each ref by iterating
> over the refs/rewritten/for-update-refs/ namespace. We cannot update the
> refs in-place since this will confuse the refs iterator.

In other words, grab everything we need to do and then use that
in-core information to tell refs API what refs to change to what
values?  That dounds like a quite reasonable thing to do.

Looking at the patch text, the only thing that stands out at me is
that this does not seem to perform the updates in a single
transaction, which may often not matter in practice, but may be a
prudent thing to do anyway at philosophical level.

Thanks, will queue.