Re: [RFC] get_sha1() shorthands for blob/tree objects

From: Junio C Hamano <junkio@cox.net>
Date: Apr 19, 2006, 04:02 UTC
Message-ID: <7v8xq2ciws.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <Pine.LNX.4.64.0604181836400.3701@g5.osdl.org>

Linus Torvalds <torvalds@osdl.org> writes:

Show 22 quoted lines

> Actually, it's not ambiguous. Just take the named file. If you want to 
> diff it against HEAD:<named-file>, you should just say so.
>
> Now, if you _really_ want to be difficult, there's a third option: to diff 
> it against the named file as named in the index. "git diff" does have the 
> "--cached" option that would make that case unambiguous too, of course.
>
> Ie:
>
>  (a) diff against the current HEAD:
>
> 	git diff v0.99.6:git-commit-script HEAD:git-commit.sh
>
>  (b) diff against the current index contents for "git-commit.sh":
>
> 	git diff --cached v0.99.6:git-commit-script git-commit.sh
>
>  (c) diff against a random file (which may not even be in the index):
>
> 	git diff v0.99.6:git-commit-script git-commit.sh
>
> are all sensible operations, and unambiguous.

A small fry in the ointment. What should the parts that are output with --name-only say for such a diff?

Blob references like v0.99.6:git-commit-script are resolved by the extended SHA1 interpreter, and all what the caller of setup_revisions() can see and feed the diff machinery with has are their object names. Something like this is a possibility, but is ugly.

        diff --git a/a2455b0... b/01c73bd...
        index a2455b0..01c73bd 100644
        --- a/a2455b0...
        +++ b/01c73bd...
        @@ -1,118 +1,509 @@
         #!/bin/sh
         #
         # Copyright (c) 2005 Linus Torvalds
        +# Copyright (c) 2006 Junio C Hamano
        +
        +USAGE='[-a] [-s] [-v] [--no-verify] [-m <message>...
        +SUBDIRECTORY_OK=Yes
        ...