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From:   Junio C Hamano <gitster@pobox.com>
To:     Elijah Newren <newren@gmail.com>
Cc:     Derrick Stolee <stolee@gmail.com>,
        Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>,
        Git Mailing List <git@vger.kernel.org>
Subject: Re: [PATCH 3/3] diff: correct warning message when renameLimit
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Date:   Tue, 13 Jul 2021 22:17:16 -0700
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Elijah Newren <newren@gmail.com> writes:

> Am I mixing up negatives/positives (as I'm prone to do), or would it
> be more correct to say the new algorithm risks suboptimal positives
> rather than that it risks false negatives?

I'm prone to mixing them up, too, but I think they are the sides of
the same coin.  Imagine there is a path X on the source side, and
two paths Y and Z on the destination side.  With exhaustive match,
Z might be a better match (content-wise) to X than Y is to X.

For the path X on the source that is matched with a suboptimal
counterpart Y on the destination side, we may call the situation a
false-positive because with a more exhaustive search we might have
been able to find Z that is a better match.  For the path Z on the
destination side that was culled too early with heuristics and
failed to be matched with the source path X that got matched with a
suboptimal destination path Y, it is a loss for Z---it wasn't chosen
when it should have been (i.e. a false negative, as Z saw no
counterparts).

In any case, during the word search for "inexact", "more precise",
"more expensive", I do not think negatives and positives will play a
big role anyway, so...