Re: [PATCH] diff: add a config option to control orderfile

[Jeff King <peff@peff.net>]

On Wed, Sep 18, 2013 at 12:03:25AM +0300, Michael S. Tsirkin wrote:

> > It may be esoteric enough not to worry about, though. By far the most
> > common use of patch-ids is going to be in a single "rev-list
> > --cherry-pick" situation where you are trying to omit commits during
> > a rebase.
> > 
> > I am mostly thinking of the problems we had with the "kup" tool, which
> > expected stability across diffs that would be signed by both kernel.org.
> > But as far as I know, they do not use patch-id.
> 
> We can always do a compatibility option. --order-sensitive ?
> --ignore-order ?

That may make sense as an escape hatch in case somebody has a use we
didn't foresee.

If it is just about "consistent order" versus "whatever is in the diff",
I do not know that we need to worry as much; only the minority using
orderfile is affected, and they have _always_ been affected. IOW, we are
fixing a bug, and they should be happier.

But if it is changing the output entirely in all cases (e.g., the
1s-complement sum), I think you would want to have a "classic" mode that
tries to be compatible with the old style (with the caveat that of
course it depends on patch ordering).

-Peff