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From:   Junio C Hamano <gitster@pobox.com>
To:     Derrick Stolee <stolee@gmail.com>
Cc:     Elijah Newren via GitGitGadget <gitgitgadget@gmail.com>,
        git@vger.kernel.org, Derrick Stolee <dstolee@microsoft.com>,
        Jonathan Tan <jonathantanmy@google.com>,
        Taylor Blau <me@ttaylorr.com>, Jeff King <peff@peff.net>,
        Karsten Blees <blees@dcon.de>, Elijah Newren <newren@gmail.com>
Subject: Re: [PATCH 1/2] diffcore-rename: no point trying to find a match
 better than exact
References: <pull.842.git.1612331345.gitgitgadget@gmail.com>
        <3e69857f37e12540f7986245b99916b68702217a.1612331345.git.gitgitgadget@gmail.com>
        <515f55bd-90e2-9a7f-0973-501c9351969e@gmail.com>
Date:   Wed, 03 Feb 2021 10:46:32 -0800
In-Reply-To: <515f55bd-90e2-9a7f-0973-501c9351969e@gmail.com> (Derrick
        Stolee's message of "Wed, 3 Feb 2021 06:44:50 -0500")
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Derrick Stolee <stolee@gmail.com> writes:

>>  	/* All done? */
>> -	if (!num_destinations)
>> +	if (!num_destinations || !num_sources)
>>  		goto cleanup;
>
> And add an extra quit condition which is very possible to hit.
> Is it only hit when every "delete" is actually a rename?

When every delete is actually an unmodified exact rename, I think.
If this simple change gives us good performance gain, that is
superb.

Nicely done.