alt Hacker NewsIs it a good thing to have merges that never fail? Often a merge failure indicates a semantic conflict, not just "two changes in the same place". You want to be aware of and forced to manually deal with such cases.
I assume the proposed system addresses it somehow but I don't see it in my quick read of this.
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It says that merges that involve overlap get flagged to the user. I don't think that's much more than a defaults difference to git really. You could have a version of git that just warns on conflict and blindly concats the sides.
Should you be counting on confusion of an underpowered text-merge to catch such problems?
It'll fire on merge issues that aren't code problems under a smarter merge, while also missing all the things that merge OK but introduce deeper issues.
Post-merge syntax checks are better for that purpose.
And imminently: agent-based sanity-checks of preserved intent – operating on a logically-whole result file, without merge-tool cruft. Perhaps at higher intensity when line-overlaps – or even more-meaningful hints of cross-purposes – are present.
Indeed. And plenty of successful merges end up with code that won't compile.
FWIW I've struggled to get AI tools to handle merge conflicts well (especially rebase) for the same underlying reason.
I agree. Nevertheless I wonder if this approach can help with certain other places where Git sometimes struggles, such as whether or not two commits which have identical diffs but different parents should be considered equivalent.
In the general case, such commits cannot be considered the same — consider a commit which flips a boolean that one branch had flipped in another file. But there are common cases where the commits should be considered equivalent, such as many rebased branches. Can the CRDT approach help with e.g. deciding that `git branch -d BRANCH` should succeed when a rebased version of BRANCH has been merged?
My understanding of the way this is presented is that merges don't _block_ the workflow. In git, a merge conflict is a failure to merge, but in this idea a merge conflict is still present but the merge still succeeds. You can commit with conflicts unresolved. This allows you to defer conflict resolution to later. I believe jj does this as well?
Technically you could include conflict markers in your commits but I don't think people like that very much
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This
They address this; it's not that they don't fail, in practice...
the key insight is that changes should be flagged as conflicting when they touch each other, giving you informative conflict presentation on top of a system which never actually fails.