From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: Possible --remove-empty bug
Date: Sun, 12 Mar 2006 21:41:51 -0800
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Cc: Marco Costalba <mcostalba@gmail.com>, git@vger.kernel.org
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To: Linus Torvalds <torvalds@osdl.org>
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Junio C Hamano <junkio@cox.net> writes:

> Linus Torvalds <torvalds@osdl.org> writes:
>
>> It's supposed to stop traversing the tree once a pathname disappears.
>
> Then what we should simplify is the parent commit that does not
> have those pathnames (i.e. remove parents from that parent
> commit).  In other words, currently the code removes the parent
> commit that makes the tree disappear, but we would want to keep
> that parent, remove the grandparents, and then mark the parent
> uninteresting.

Sorry, the last clause in the above comment is wrong, and does
not describe what the code attached does.

It removes the grandparents from the parent, and leaves the
parent still interesting.  As a result, in your example:

    ... if you have

                a
               / \
              b   c
               \ /
                d

    where the pathname disappeared in "b"...

we would get this world view:

                a
               / \
              b   c
                 /
                d

because when inspecting a and finding that "b" does not have any
paths we are interested in, b loses all of its parents.