Re: Interdiff between amended commits

From: Michael J Gruber <git@drmicha.warpmail.net>
Date: Apr 14, 2011, 07:08 UTC
Message-ID: <4DA69D7F.5050304@drmicha.warpmail.net>
In-Reply-To: <1jzlxb0.12qxbsl1na9qhzM%lists@haller-berlin.de>

Stefan Haller venit, vidit, dixit 13.04.2011 13:54:

Show 7 quoted lines

> I'd like to show an interdiff between two commits, e.g. when a commit
> was amended.
> 
> I'm aware of the "intercommit" alias in the git wiki:
> 
>   $ git show commit1 > .git/commit1 && git show commit2 > .git/commit2 && interdiff .git/commit[12]
>

This basically computes the diff between two patches, using a tool which groks the patch format.

> It only works for simple cases though, and I'd also like to avoid the
> dependency to an external tool if possible.

You could use git diff --no-index instead, so that would work in really simple cases only, probably.

Show 6 quoted lines

> 
> So one thing I came up with is this:
> 
>   git checkout commit1^
>   git cherry-pick --no-commit commit2
>   git diff --cached

That does something completely different. It compares the tree of commit1^ with the tree of (commit1^ with commit2's patch applied). I don't see how commit1's patch plays any role here.

Depending on what your actual use case, you may be happier with "git diff commit1 commit2". Alternatively, you may produce a fake merge with parents commit1 and commit2 and tree commit1^ and look at "show -R -c" for that. Sounds weird, I know ;)

Michael