Using Git's rerere feature to escape recurring conflict hell

(gist.github.com)

45 points | by ankitg12 8 hours ago

6 comments

  • dools 1 hour ago
    I never get conflicts during a merge because I only ever merge in one direction. I get all my conflicts on branches because I rebase before merging. I started doing this years and years ago because I kept coming across these mysterious silent regressions with my team. I searched something like "git merge silent regressions" and came across this stackoverflow answer:

    https://stackoverflow.com/a/28510260

    That completely fixed the problem. Now I only ever get conflicts on my feature branches. The rule is always: rebase away from main, and merge towards main. All conflicts are then on your branches, never on main, and always from rebase, never from merge. Then I set the pull behaviour to rebase, too.

    I've never had a silent regression since, and never had a problematic conflict scenario.

    I did recently learn about ORIG_HEAD though which was very cool, because I had accidentally rebased to main instead of to a dev branch from which I had created a bunch of worktrees, then when I merged back to the dev branch all hell broke loose, and I learned that I could revert a merge by checking out ORIG_HEAD:

    https://icinga.com/blog/undo-git-reset-hard/

    • barbazoo 32 minutes ago
      rerere is still useful here to handle merge conflicts after repeated rebases.
    • ubercore 1 hour ago
      I've never even seen someone suggest a rebase master onto feature workflow! TIL.
      • dools 1 hour ago
        I think the terminology would be the other way around, like you're rebasing the feature onto the main:

        git checkout feature

        git rebase main

        git checkout main

        git merge feature

        that way you get all your conflicts on the feature branch during rebase and your merge is always clean.

      • barbazoo 30 minutes ago
        > I get all my conflicts on branches because I rebase before merging

        Pretty sure it's the other way around. You're on the branch and rebase it atop current master. If you merge after that, you won't have merge conflicts.

  • mamcx 7 minutes ago
    I use rerere when "forced" by team to use rebase. It not even work that much at the end (you can't control workflows outside yourself, that is why git ux is wrong: it desperately need total discipline).

    THEN, I move to jujutsu. Only has a few problems at start trying to use it as git, but after get the idea, all fine.

    BTW, this was with the same team and they never know, so JJ is in fact better: It survive OTHERS workflows.

  • 0123456789ABCDE 2 hours ago

      #~/.config/git/config
      [rerere]
          enabled = true
          autoUpdate = true
    
    while you're editing git config, consider these:

        [pull]
          rebase = true
    
      [rebase]
          autoSquash = true
          autoStash = true
    
      [merge]
          # zdiff3 adds original text markers and removes matching lines from conflict regions
          # https://git-scm.com/docs/git-config#Documentation/git-config.txt-mergeconflictStyle
          conflictStyle = zdiff3
          autoStash = true
    
      [push]
          autoSetupRemote = true
          default = simple
    
      [init]
          defaultBranch = main
    • 0123456789ABCDE 24 minutes ago
      addendum

      these are changes tacked to my git config over time. they're the result of working in a constant crunch state, where smooth forward move was more import than the state of the git history you left behind. these options remove small annoying road bumps. you should avoid some of them if you're working under different constraints, or the commit process differs such that these options don't apply.

      it all starts with `pull.rebase=true` it makes `git pull --rebase` the default behavior. then comes `rebase.autoStash`, which just wraps the rebase with a stash push/pop envelop. if rebase is not your thing, and you prefer merge, `merge.autoStash=true` works the same. finally `push.autoSetupRemote=true` will skip asking you to set a remote tracking branch, it makes `git push` default to `git push --set-upstream`.

    • Izkata 15 minutes ago

          [pull]
            rebase = true
      
      Don't use this one unless you really know what you're doing. Multiple co-workers gave gotten into really bizarre rebases because of it (like rebasing 70+ commits from master on top of their branch instead of the other way around), it seems to cause more problems than it solves.

      The man page for "git pull" even has a warning about using this flag.

  • adithyassekhar 1 hour ago
    Do people really merge left and right between branches? Tell me if I got this wrong, this is how I work.

    You got 4 devs. Each branched off from master. And we never merge from each other. Suppose 3 other people merged to master I pull it from master and fix only those conflicts. I’m not bringing your code into my branch unless it’s already finished and on master. If I need something you’re working on and it’s not on master when I need it, it’s a much larger planning issue.

    If you have multiple environments before a stable master, do it only in one direction: feature > dev > staging > master. Don’t merge branches straight into staging or master.

    I thought this was how everyone worked.

    • powersjcb 25 minutes ago
      Yeah, I absolutely never run into this problem.

      Sometimes we will have a huge stack of changes one of us is "finished but not clear to merge".

      either:

      - We just swap ownership of the branches and eng 2 now commits directly in branch 1. We review the final content together and typically pull in a 3rd person to review our combined work. Eng 1 either pairs with eng 2 until its finished or starts on a task that is decoupled from those changes.

      - We use an integration branch that gets threated like the temporary master branch until the feature is ready to merge.

    • convolvatron 10 minutes ago
      when you're not just doing small patches (like Greenfield work), and you have multiple developers, it can be unreasonable and wasteful to do what you describe. say we're redoing the way memory management it being done, or changing a foundational api. A and B could go through master, but they'd have to redo a whole bunch of work. Or we could make an integration branch where A and B hash things out together and only push to master when their work is done. you can also see how this allows a lot more back and forth about the places where the designs interact rather than 'I got in master before you, so you get to eat a multi-day merge and I'm outta here'

      this kind of interaction shows up more in a 'release' based model than CI environment, and one where the cost of testing is non-zero (because we're actually doing testing). I know that's not a very popular model, but not all software development is CI websites.

  • davidelettieri 2 hours ago
    I'm using these options https://blog.gitbutler.com/how-git-core-devs-configure-git and I'm happy with it
  • cautiouscat 2 hours ago
    Every time I think I am adept in git, something like this is shown to me. I really should read into it more lol.