[Haskell-cafe] Re: [ANNOUNCE] git-darcs-import 0.1

This is drifting off-topic, but... On 2008-06-03, Peter Hercek wrote:

Aaron Denney wrote:

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On 2008-06-03, Peter Hercek wrote:

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Loup Vaillant wrote:

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2008/6/3 Darrin Thompson :

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<--cut--> What's the appeal of this? I personally love git, but I thought all the cool kids at this school used darcs and that was that. Disclaimer: I'm no expert, this is what I've heard. Anyone please confirm or deny the following?

Basically, git is waaay faster than Darcs on a number of use cases. Other reason can be "git rebase". Of course there is a question how good practice it is ... but it is being used.

Darcs patches are pretty much an implicit rebase.

You cannot push patch B if it depends on patch A without also pushing A. And darcs currently does not alow you to reorder B before A

True. This is a *feature* not a bug. You shouldn't be able to do this automatically, because it can't be done right. You need to do this sort of thing manually. If you don't, the heuristics used will bite you at some point. When they do commute, there is no problem.

Git rebase works quite well even in cloned repositories.

Meh. It can, if you're really really lucky.

See: http://bugs.darcs.net/issue891 Some discussin about it is also here: http://lists.osuosl.org/pipermail/darcs-users/2008-February/011564.html

When the issue is fixed then darcs will be really patch based and will become the ultimate DSCM :-)

Rebasing is doable in git as a one-repository operation because each repository has multiple branches. As darcs has one repo per branch, it fundamentally needs to be done in multiple repos. There are naturally two repos, upstream, and your-feature-development. your-feature-development has a patch A that you want to rebase. What you should do is pull upstream into new-tracking, then pull patch A from your-feature-development into new-tracking. If it applies with no problem, great: mv your-feature-development your-feature-development-old; new-tracking your-feature-development. Of course, in this case, you could have just pulled into your-feature-development. If there weren't any other patches to save in the old your-feature-development, you can delete it instead of moving it. When there is a conflict, then you need to handle it somehow. Neither git nor darcs can do it automatically. You can just record the merge conflict and your resolution. This keeps repos that pulled from you valid, but this won't give you the "clean history" that you presumably want. So you need to combine the merger and cleanup into a new patch with the same log message, etc. It's true that git does make *this* process very nice. There is one thing that git rebase does easily (and correctly) that darcs doesn't do nicely: rewriting history by merging commits "prior" to the head. I put prior in quotes, because darcs doesn't preserve history in the first place. I don't find that a compelling use, as opposed to maintaing topic branches. -- Aaron Denney -><-