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From:   Junio C Hamano <gitster@pobox.com>
To:     Johannes Schindelin <Johannes.Schindelin@gmx.de>
Cc:     Thomas Guyot-Sionnest <tguyot@gmail.com>,
        Jeff King <peff@peff.net>, git@vger.kernel.org,
        Thomas Guyot-Sionnest <dermoth@aei.ca>
Subject: Re: [PATCH 1/2] diff: Fix modified lines stats with --stat and
 --numstat
References: <20200918113256.8699-1-tguyot@gmail.com>
        <20200918113256.8699-2-tguyot@gmail.com>
        <20200918172747.GD183026@coredump.intra.peff.net>
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        <nycvar.QRO.7.76.6.2009231709340.5061@tvgsbejvaqbjf.bet>
Date:   Wed, 23 Sep 2020 12:23:46 -0700
In-Reply-To: <nycvar.QRO.7.76.6.2009231709340.5061@tvgsbejvaqbjf.bet>
        (Johannes Schindelin's message of "Wed, 23 Sep 2020 21:16:20 +0200
        (CEST)")
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Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

> I believe that that is exactly the reason why we want this:
>
> -	same_contents = oideq(&one->oid, &two->oid);
> +	same_contents = one->oid_valid && two->oid_valid ?
> 		oideq(&one->oid, &two->oid) : !strcmp(one->data, two->data);

Not quite.  The other side should either be

	one->size == two->size && !memcmp(...)

or just left to false, as the downstream code must be prepared for
same_contents being false even when one and two turns out to be
not-byte-for-byte-same but equivalent anyway.