From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] git-new-workdir: support submodules
Date: Sun, 25 Jan 2015 21:39:25 -0800
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Cc: git@vger.kernel.org, Jonathan Nieder <jrnieder@gmail.com>,
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To: Craig Silverstein <csilvers@khanacademy.org>
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	(Craig Silverstein's message of "Sun, 25 Jan 2015 20:57:49 -0800")
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Craig Silverstein <csilvers@khanacademy.org> writes:

> This patch, in adding submodule support, I expect would be
> similarly useful to people even though it, also, imposes those
> same constraints to the submodule's config files.

I would expect that you would see exactly the same issue with Duy's
multiple work tree series.  This is not limited to new-workdir.

The right way to look at this is to fix what "git submodule" does;
its use of "config" that is shared across branches is the root cause
of the trouble.  No other part of Git keeps data that needs to be
per-branch (or more specifically "tied to the working tree state")
in .git/config in such a way that leaving it stale when the working
tree state changes breaks the system.

One way to do so might be to move the bits it stores in the config
file to somewhere else that is more closely tied to the checkout
state and handle that similar to .git/index and .git/HEAD when it
comes to multiple work-trees.