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From: Junio C Hamano <gitster@pobox.com>
To: Phillip Wood <phillip.wood123@gmail.com>
Cc: Antonin Delpeuch <antonin@delpeuch.eu>,  git@vger.kernel.org,  Elijah
 Newren <newren@gmail.com>
Subject: Re: [PATCH] merge-file: add --diff-algorithm option
In-Reply-To: <de04aec0-a195-45da-8951-bb30f2a629a3@gmail.com> (Phillip Wood's
	message of "Sun, 19 Nov 2023 16:43:19 +0000")
References: <pull.1606.git.git.1699480494355.gitgitgadget@gmail.com>
	<653b08fd-2df3-4a7a-8082-fdb809e87784@delpeuch.eu>
	<de04aec0-a195-45da-8951-bb30f2a629a3@gmail.com>
Date: Mon, 20 Nov 2023 08:30:25 +0900
Message-ID: <xmqq7cmdpbhq.fsf@gitster.g>
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Phillip Wood <phillip.wood123@gmail.com> writes:

> I can see there's an argument for changing the default algorithm of
> "git merge-file" to match what "ort" uses. I know Elijah found the
> histogram algorithm gave better results in his testing when he was
> developing "ort". While it would be a breaking change if on the
> average the new default gives better conflicts it might be worth
> it. This patch would mean that someone wanting to use the "myers"
> algorithm could still do so.

Sounds like a sensible thing to do.  First allow to configure the
custom algorithm from the command line option (and optionally via a
configuration variable) and ship it in a release, start giving a
warning if the using script did not specify the configuration or the
command line option and used the current default and ship it in the
next release, wait for a few releases and then finally flip the
default, or something like that.

Thanks.