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From:   Junio C Hamano <gitster@pobox.com>
To:     Karthik Nayak <karthik.188@gmail.com>
Cc:     git@vger.kernel.org, me@ttaylorr.com
Subject: Re: [PATCH v4] revision: add `--ignore-missing-links` user option
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        (Karthik Nayak's message of "Sun, 24 Sep 2023 18:14:30 +0200")
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Date:   Mon, 25 Sep 2023 09:57:08 -0700
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Karthik Nayak <karthik.188@gmail.com> writes:

> Let me prefix with saying that I was partly wrong. `--missing` does work for
> trees, only that it's ineffective when used along with the
> `ignore_missing_links` bit.
>
> But for commits, `--missing` was never configured to work with. I
> did a quick look at the code, we can do something like this for
> commits too, i.e.  add support for the `--missing` option. We'll
> have to add a new flag (maybe MISSING) so it can be set during
> within `repo_parse_commit_gently` so we can parse this as a
> missing object in rev-list.c and act accordingly.

Do you mean that process_parents() would now throw such a commit to
the resulting list successfully instead of omitting when "--missing"
is requested?  That sounds like a right thing to do but at the same
time is a fix with major impact.  I do not offhand know what the
ramifications are, for example, when bitmap traversal is in use (I
assume such a missing commit would not be catalogued in the bitmap?).

Taylor, what do you think?