Re: [RFC] Importing from a patch-oriented SCM

From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Aug 19, 2005, 08:29 UTC
Message-ID: <Pine.LNX.4.63.0508191023570.11916@wgmdd8.biozentrum.uni-wuerzburg.de>
In-Reply-To: <46a038f9050819000417ed436e@mail.gmail.com>

Hi,

On Fri, 19 Aug 2005, Martin Langhoff wrote:

Show 6 quoted lines

> Each patchset has a unique identifier, and can carry metadata with the
> identifiers of the patches it "includes". If you are using gnu arch,
> when you merge across branches, it'll know to skip a particular
> patchset if it has been applied already. AFAICT there is no such
> concept in GIT, and I wonder what to do with all this metadata about
> merges.

You should include the metadata in the commit object. If the information is about parents, they should be parents in git, too. If the information is something else, you should convert it to readable text and put it in the comment part of the commit object.

> If I remember correctly, Junio added some stuff in the merge & rebase
> code that will identify if a particular patch has been seen and
> applied, and skip it even if it's a bit out of order.

The usual way of git is to use a 3-way merge: given a common ancestor, try to apply the changes between the ancestor and the second branch to the first branch. And yes, this does not take history into account. Originally, I wanted to write an "intelligent" merge, which turns the history into patches and tries to merge these, but ultimately I got convinced that this is too complicated to be worthwhile.

Ciao, Dscho