From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] unpack-trees: don't update files flagged for deletion
Date: Fri, 17 Jul 2015 13:05:19 -0700
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References: <1437162532-31933-1-git-send-email-dturner@twopensource.com>
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Cc: git@vger.kernel.org, Anatole Shaw <git-devel@omni.poc.net>
To: David Turner <dturner@twopensource.com>
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In-Reply-To: <1437162532-31933-1-git-send-email-dturner@twopensource.com>
	(David Turner's message of "Fri, 17 Jul 2015 15:48:52 -0400")
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David Turner <dturner@twopensource.com> writes:

> Don't update files in the worktree from cache entries which are
> flagged with CE_WT_REMOVE.  This is fixes merges in sparse
> checkouts.

s/This is/This/;

But more importantly, what is missing is "why" it is a good fix.
i.e. things like:

 - why is it wrong to update what is marked with CE_UPDATE bit to be
   updated in the working tree when CE_WT_REMOVE bit is on?

 - how that incorrect operation breaks which operation in what way?

 - how does the changed code fix that breakage?