[xmonad] Upgrading repo formats

[Gwern Branwen]

On Mon, May 3, 2010 at 11:58 AM, Spencer Janssen
<spencerjanssen at gmail.com> wrote:
> On Sun, Apr 25, 2010 at 10:14:28PM -0400, Gwern Branwen wrote:
>> On Fri, Apr 23, 2010 at 3:40 PM, adam vogt <vogt.adam at gmail.com> wrote:
>> > On Sat, Apr 10, 2010 at 1:16 PM, Gwern Branwen <gwern0 at gmail.com> wrote:
>> >> While waiting on a slow connection today to darcs get XMC, I had time
>> >> to ponder. The patches are (or would be) in my global cache, so it
>> >> could go much faster. Why doesn't it? Because xmonad-contrib and
>> >> xmonad-core are both still using darcs-1 fomatted repositories.
>> >>
>> >> Is there any particular reason to not upgrade? Even Debian Stable has
>> >> Darcs 2.x (http://packages.debian.org/lenny/darcs), so it's not as if
>> >> there are many people who would be unable to do a darcs get.
>> >>
>> >> --
>> >> gwern
>> >
>> > I support this.
>> >
>> > Since this isn't something we can easily rollback, (without the messy
>> > situation of keeping the unupgraded repository updated in parallel), it
>> > is important to have some consensus before updating repo formats.
>>
>> What now? Nobody has objected here, and it's been several days, so I
>> would guess not many will object in the future.
>>
>> I would point out that besides the mere 12 pulls using darcs 1.x this
>> month - which could all be due to just 1 user - Xmonad has broken ghc
>> 6.6 support, and I wouldn't be surprised if ghc 6.8 support was now
>> broken. So anyone actually *using* darcs xmonad-core/xmonad-contrib
>> must be using a recent GHC, and there are Darcs 2.xs which support 6.8
>> and probably 6.6 as well.
>>
>> Which implies that anyone using darcs xmonad is capable of upgrading
>> to Darcs 2. We don't to worry about anyone locked down to Darcs 1.x.
>>
>> The question is whether we have the will to actually upgrade the repos
>> and make people re-'darcs get' the repos.
>>
>> I think we do, and that the long-term benefits of cached patches and
>> fewer conflicts and active Darcs support and whatnot justify the
>> short-term pain. But ultimately, while I could unilaterally upgrade
>> xmonad-contrib, dons and sjanssen are the only ones who can upgrade
>> xmonad-core, and I'd feel pretty silly doing only half the job.
>>
>> --
>> gwern
>
> I do support switching, but I do have one concern.  As I understand it,
> after switching we won't be able to apply any darcs 1 patches to the darcs 2
> repo.  We would need to resolve any outstanding forks and clean up all the
> pending patches on the mailing list.

darcs convert --help says

"WARNING: the repository produced by this command is not understood by
Darcs 1.x, and patches cannot be exchanged between repositories in
darcs-1 and darcs-2 formats."

(I also just converted xmonad-core and tried applying one of the old
patches; didn't work.)

> Also, is there some documentation or a guide for converting?  I really don't
> want to screw up our repository.

http://darcs.net/manual/node7.html#SECTION007111000000000000000 I think.

-- 
gwern