From: Stefan Monnier <monnier@iro.umontreal.ca>
To: git@vger.kernel.org
Subject: Re: Can't diff against the 00000000 revision
Date: Tue, 12 Jan 2016 11:26:24 -0500 [thread overview]
Message-ID: <jwvr3hmwz1n.fsf-monnier+gmane.comp.version-control.git@gnu.org> (raw)
In-Reply-To: 20160112153239.GA8041@sigill.intra.peff.net
>> I currently work around the problem by adding a dummy empty branch, but
>> being able to use the revision 00000000 as a known reference to an empty
>> tree would come in really handy, and since it's already used at various
>> places in Git (post-receive hook and "git show" output, at least), it
>> would seem like a natural extension.
> The empty tree also has a name:
>
> $ git hash-object -t tree /dev/null
> 4b825dc642cb6eb9a060e54bf8d69288fbee4904
Yay!
git diff 4b825dc642cb6eb9a060e54bf8d69288fbee4904..d59cfff346c3e210adc26501f8cebf8da5ab2e7d
seems to give me the expected diff.
Thanks!
> And hopefully that explains why "000000" does not necessarily make a
> good placeholder for "the empty thing". There are multiple empty things,
> and it is not clear what:
> git diff 0000000 1234abcd
> means. Is 0000000 a tree? A blob?
Well, Git is the one who uses 000000 to refer to an empty thing, but
indeed it seems like it does inconsistently: it's sometimes used as the
"empty blob" and sometimes as an "empty tree".
Stefan
next prev parent reply other threads:[~2016-01-12 16:26 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-12 15:17 Can't diff against the 00000000 revision Stefan Monnier
2016-01-12 15:32 ` Jeff King
2016-01-12 15:37 ` Jeff King
2016-01-12 16:26 ` Stefan Monnier [this message]
2016-01-12 18:20 ` Jeff King
2016-01-12 18:52 ` Junio C Hamano
2016-01-12 18:11 ` Andreas Schwab
2016-01-12 18:21 ` Jeff King
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