Re: [PATCH 1/3] revision: support tracking uninteresting commits

From: Derrick Stolee <derrickstolee@github.com>
Date: Apr 25, 2023, 18:15 UTC
Message-ID: <0b8884ea-f37b-b7d4-6edb-825ca935a893@github.com>
In-Reply-To: <a643678c0ff7d1a910b1d6c33a839166e2a6a7b2.1682380788.git.me@ttaylorr.com>

On 4/24/2023 8:00 PM, Taylor Blau wrote:

Show 5 quoted lines

> The boundary-based bitmap walk will want to know which commits were
> marked UNINTERESTING in the walk used to discover the boundary.
> 
> Track which commits are marked as such during list limitation as well as
> the topo walk step, though the latter is not used.

I was surprised to see this as an addition to revision.c, and only specific to limit_list() (and its iterative copy). I would expect this to work for non-topo-order, too. I suppose we couldn't completely trust that the first visit to a commit includes the UNINTERESTING flag if there is clock skew in the commit history.

But could we also do this at the caller's end by passing a callback that checks each walked commit if it is UNINTERESTING and adds it to a set?

I know that the walking code in builtin/pack-objects.c does this same computation, but it's muddled with other checks and the trees are marked as UNINTERESTING at the same time. It doesn't seem like we can reuse anything directly out of there, but it did give me the idea to try a callback.

Thanks, -Stolee