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Date: Thu, 7 Dec 2023 15:47:13 -0500
From: Taylor Blau <me@ttaylorr.com>
To: Patrick Steinhardt <ps@pks.im>
Cc: git@vger.kernel.org, Jeff King <peff@peff.net>,
	Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH 16/24] pack-objects: prepare `write_reused_pack()` for
 multi-pack reuse
Message-ID: <ZXIvUfRaXUxB+m7w@nand.local>
References: <cover.1701198172.git.me@ttaylorr.com>
 <67a8196978244b56d4f60861f140b78c59d15e30.1701198172.git.me@ttaylorr.com>
 <ZXHE-cLrP7iRHWHY@tanuki>
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In-Reply-To: <ZXHE-cLrP7iRHWHY@tanuki>

On Thu, Dec 07, 2023 at 02:13:29PM +0100, Patrick Steinhardt wrote:
> On Tue, Nov 28, 2023 at 02:08:37PM -0500, Taylor Blau wrote:
> > The function `write_reused_pack()` within `builtin/pack-objects.c` is
> > responsible for performing pack-reuse on a single pack, and has two main
> > functions:
> >
> >   - it dispatches a call to `write_reused_pack_verbatim()` to see if we
> >     can reuse portions of the packfile in whole-word chunks
> >
> >   - for any remaining objects (that is, any objects that appear after
> >     the first "gap" in the bitmap), call write_reused_pack_one() on that
> >     object to record it for reuse.
> >
> > Prepare this function for multi-pack reuse by removing the assumption
> > that the bit position corresponding to the first object being reused
> > from a given pack may not be at bit position zero.
>
> Is this double-negation intended? We remove the assumption that we start
> reading at position zero, but the paragraph here states that we remove
> the assumption that we do _not_ start at bit zero.

Oops, great catch. I'll s/may not/must in the last paragraph to clarify.

> I'll stop reviewing here and will come back to this series somewhen next
> week.

Thanks as usual for your review -- I appreciate you digging through this
rather dense series.

Thanks,
Taylor