Subject: Re: [StGit PATCH] edit: Allow setting git tree SHA1 of a patch

From: David Kågedal <[email-masked]>
Date: Fri, 21 May 2010 15:59:23 +0200

Catalin Marinas <[email-masked]> writes:

> Hi Gustav,
>
> 2010/5/16 Gustav Hållberg <[email-masked]>:
>> I would like to have something similar to this patch, which allows for
>> setting the (git) tree of a particular patch. I would like to use it
>> (from the Emacs mode) to make it easier to split an old patch into two
>> (or more).
>>
>> It might be that this is too "powerful" (read: unsafe), and maybe a
>> better (safer) command would use whatever is currently in the index
>> rather than a SHA1.
>
> I'm not against such option (as long as it is somehow mentioned that's
> dangerous) though I don't fully understand how one would use it,
> especially when the patch is buried under other patches. With a series
> of patches, any easily accessible tree (sha1) belongs to one of the
> patches.

The idea is that Gustav wants to allow the editing of a file as it
appears in an earlier version. Lets say you have patches A, B, C and
D. You realize that one of the changes in to foo.c in C shuold really be
done in A. So you open the "A version of foo.c" in your editor, do the
change, and then save it. The save operation needs to update A to be
the new tree that contains the updated foo.c, and the remaining patches
will keep their tree. The effect is that the moved change now appears as
a diff in A, but not in C (nor B or D).

Working like this means that we don't really see the series as a string
of pateches, but as a series of named commits that we can go back and
edit. But this is a natural way of working with it once the tools get
powerful enough to support it.

-- 
David Kågedal