From: Junio C Hamano <gitster@pobox.com>
Date: Fri, 18 Dec 2009 23:46:55 GMT
Subject: Re: [PATCH 2/2] read-tree: at least one tree-ish argument is required
Message-ID: <7vr5qrsv4g.fsf@alter.siamese.dyndns.org>
In-Reply-To: <m3d42cc4i8.fsf@localhost.localdomain>

Jakub Narebski <jnareb@gmail.com> writes:

> Johannes Sixt <j.sixt@viscovery.net> writes:
>
>> Running read-tree without any arguments purges the index, but this is not
>> documented. This behavior is dubious at best because contrary to many
>> other commands, it does not use HEAD if nothing else is specified.
>> 
>> If one really wants to clear the index, this can be achieved with
>> 'git rm --cached .' or 'rm -f .git/index' in a more explicit way.
>
> One can (I think) also always use "git read-tree <empty tree>",
> where <empty tree> = 4b825dc642cb6eb9a060e54bf8d69288fbee4904

Come on.  If you genuinely believe that

    $ git read-tree 4b825dc642cb6eb9a060e54bf8d69288fbee4904

is a better way to purge the index than

    $ git read-tree

then you need to get your head examined.  No, read-tree does not default
to examine HEAD and that will not change ;-).

Besides, read-tree is a plumbing.

Come back with a proof that there has never existed any script that uses
"read-tree" without arguments to purge the index, and I'd immediately
accept and apply the patch to retroactively forbid what the implementation
has allowed users to do for a long time.  Otherwise, I won't be involved
in discussing this before the next release is cut, as a change like this
needs a reasonable transition strategy as usual, and needs to happen after
the next release.