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Git's patching functionality is pretty awful in actual practice. For example, try building a git patch that applies a standard set of patches between two divergent (vendored) kernel trees. It's usually a mess.

It's also pretty easy to find a set of patches that have to be applied in order. Then someone copies those patches onto another divergent tree, which has it's own set of custom patches without renaming. This is dangerous in git and probably sensible in pijul.

Haven't use pijul in practice, but it's not hard to imagine being better than git here.

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I think patching/cherry-picking is just inherently complicated and needs intelligence applied. I don't think Pijul is going to be any better here.
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I remember working with darcs 20 years ago (pijul should be on that lineage) and cherry picking in that was way better than doing it with git since it meant "get this change and all the required ones" rather than "pick this commit".

It still required intelligence (changes across files may not be tracked as dependent but actually are) but it was a different experience from what git provides.

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If you really wanted, you could implement this on top of a snapshot based system by mixing in git blame information (or an algorithm that is similar). It's not hard to compute that text based dependency graph on the fly, though maybe expensive without caching.
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Cherry picking is just convenience for something that anyone could do manually. If it didn't exist in the VCS, people would do it anyway and make tools to do it.

Fossil's implementation is the best, since a cherry-picked commit always points back to its origin.

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For patch sets/commutation, I find their system appealing. I think it’s tempting to yearn for something better still (eg darcs had a kind of sed-like patch that could apply its search to patches that are merged with it). If you look at how big companies do development, code review, CI, etc into monorepos, this is typically done with diff-focused thinking. Having the VC system and associated metadata attached to the individual patches (or sets thereof) feels like it could be an improvement over rebases or complex merge structures.
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> Git can checkout only a set of files or directories

How do you do this? With submodules / subtrees?

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git sparse-checkout
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Speaking as a former Darcs user (Darcs is another patch-based VCS that Pijul draws inspiration from):

"This is a useless property because the graph is only encoded at the patch layer. In the real world you have far more semantic dependencies than patch dependencies. ie, I have a patch that adds a function that calls a function added in another patch. Pijul doesn't know about that."

Darcs solved this in two different ways.

1. Dependencies. While Darcs patches would inherently "depend" on the last patch which affected the same lines, the committer could specify other patches as dependencies, handling exactly the case you described.

2. Practicality. In reality, there's no scenario where someone is pulling your "use function X" patches and also not pulling the "define function X" patch. They could if they really want to, but this would be a lot of effort for a deliberately bad result. It would be like, in Git, cherry-picking the "use" patches without the "define" patches. In neither system would this happen by accident.

"Conflicts coming back is not an issue in git. For some reason people think they need to use rebase when they should almost always be using merge."

There's a big difference between "conflicts shouldn't come back as long as everyone does what I want" and "conflicts don't come back". As long as you're using Git with other people, the rebase-lovers and their problems will be a perpetual issue. I've been on 3 teams in a row with this problem.

I deliberately moved away from Darcs after a few years - the benefit of snapshot VCS is that you don't just have the change, but you have the whole context in which the change happened. (Also branch discovery in Darcs basically doesn't exist; Pijul fixed this, at least!) I love Fossil and Mercurial for their adherence to accurate history.

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What I want is a system that records how conflicts are resolved and tries to apply that resolve. Lets say I have apply patch A, then patch B, there is a conflict, I resolve it. Then someone else applies patch B and then patch A. The VCS should know that this conflict is already resolve and apply the solution. Likewise when applying first patch C, then A and B, it should let you resolve the conflict from AB to ABC and again record the resolved conflict for the future. I'm actually fine with manually resolving conflicts, but don't want to it twice if I don't have to. This would be a great way to organize something like dwm, but I couldn't get it to work with pijul at all.
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> 1. Dependencies. While Darcs patches would inherently "depend" on the last patch which affected the same lines, the committer could specify other patches as dependencies, handling exactly the case you described.

I don't know who would want to put in the work of mapping out the semantic dependency graph because maybe some day someone might want to compose a slightly different set of patches. And even if everyone tried, it would surely still fail because that's so hard or impossible.

> There's a big difference between "conflicts shouldn't come back as long as everyone does what I want" and "conflicts don't come back". As long as you're using Git with other people, the rebase-lovers and their problems will be a perpetual issue. I've been on 3 teams in a row with this problem.

Just stop using rebase is much easier to socialize than let's all move to Pijul. It's also the correct thing to do.

> the benefit of snapshot VCS is that you don't just have the change, but you have the whole context in which the change happened.

I strongly agree with this and think it's the only tractable way to operate.

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