RFC: Rename jj backout to jj revert

[zx8]

Forking this discussion from #5676 (comment)

The name of this subcommand is something that stood out to me from the moment I started using jj and instinctively looked for a revert subcommand in the output of jj --help. Revert feels like a naturally better name to me, coming from Git.

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Does anyone strongly prefer "back out"? Our current template is identical to Git's except that Git says "revert". I find "back out" somewhat awkward and not more accurate, so I would prefer we adjust the default template and rename the command.

— @emilazy in #5676 (comment)

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FWIW, I agree @emilazy

It also mildly irks me that the subcommand is jj backout while the verb form is two separate words "back out".

"Revert" is both more familiar to Git users and a single word in both forms.

— @zx8 in #5676 (comment)

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@martinvonz said in #5397 (comment):

revert is confusing for hg users (hg revert is jj restore). We could still use that, or we could use reverse. Another option is rollback (or roll-back to be more grammatically correct).

Personally I think a little confusion for Mercurial users an acceptable cost for what I think is the better name (we confuse Git users a fair bit already!). I don’t mind reverse either, but I think it’s more ambiguous (maybe it could reverse commit ordering?) and the Git terminology is good enough that we can just reuse it.

— @emilazy in #5676 (comment)

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Looking into things a bit further, StackOverflow conducted a survey in 2023 that revealed around 1% of developers use Mercurial. I don't think this is a compelling enough reason to fumble around trying to find a different name (reverse, rollback, roll-back, etc. were floated @ #5397 (comment)) to avoid confusing such a small percentage of VCS users.

So, what does everyone think about renaming jj backout to jj revert?

[PhilipMetzger]

In my opinion both backout and rollback are a more appropriate name for the command since Jujutsu is no Git descendant (its command-line interface is shaped like Mercurial) and while familiarity is "great" for people coming from Git, the project shouldn't optimize for it.

[joyously]

To me, revert sounds like it moves a pointer in a stack of things (sort of like an undo), which in jj is restore?
The description suggests invert.
I would not have guessed backout to be a match for the description. It seems like abandon is better suited for it.
Maybe there are too many commands, and several should be condensed to one command with options, much like how squash was.

[emilazy]

In my opinion both backout and rollback are a more appropriate name for the command since Jujutsu is no Git descendant (its command-line interface is shaped like Mercurial) and while familiarity is "great" for people coming from Git, the project shouldn't optimize for it.

I don’t think being used in Git is an argument against a name, though, if it’s better than the Mercurial name (and I don’t think being used in Mercurial is an argument for a name either, really). I think backout is a bad name.

Personally rollback makes me think of jj undo/jj op restore more than revert does.

Personally I haven’t heard a name I like better than revert and I think revert is just fine. I wouldn’t mind invert.

[PhilipMetzger]

n my opinion both backout and rollback are a more appropriate name for the command since Jujutsu is no Git descendant (its command-line interface is shaped like Mercurial) and while familiarity is "great" for people coming from Git, the project shouldn't optimize for it.

I don’t think being used in Git is an argument against a name, though, if it’s better than the Mercurial name (and I don’t think being used in Mercurial is an argument for a name either, really). I think backout is a bad name.

If it being used in Git is not an argument against it then it neither is one in favor of it. Since Jujutsu actually is something new, some unfamiliarity should be a given for users coming from Git, but that is not a bad thing.

[martinvonz]

I think I also like revert best (even though I'm the one who picked backout).

Is it worth coordinating a rename with the change in behavior we've talked about (#2802)? We could do it by adding revert with the new behavior and deprecating backout (without changing its behavior).

[zx8]

If it being used in Git is not an argument against it then it neither is one in favor of it. Since Jujutsu actually is something new, some unfamiliarity should be a given for users coming from Git, but that is not a bad thing.

@PhilipMetzger That's a reasonable assessment based on the OP. Re-reading my OP, I can see how it came across as "This is what is used ingit, so it makes sense to do the same in jj!" – but that wasn't my intention at all.

The reality is, I simply think "revert" is better terminology here, and is what I use in day-to-day parlance when speaking with colleagues, e.g. it feels natural to me to say to someone "Could you please revert yesterday's change?" but appreciate this could be a cultural difference.

[emilazy]

If it being used in Git is not an argument against it then it neither is one in favor of it. Since Jujutsu actually is something new, some unfamiliarity should be a given for users coming from Git, but that is not a bad thing.

I just think that either previous systems are irrelevant and we shouldn’t talk about them at all, or familiarity with Git can only, all else being equal, be a positive – perhaps a very mild positive, but not a negative, as long as the name is good on its own merits and the familiarity doesn’t lead to an inaccurate perception. If I thought git revert was a bad name I wouldn’t suggest it, but I think it’s better than hg backout, I can’t think of anything that seems strictly better, and so Git familiarity is just a cherry on top. “Git uses this name, so we shouldn’t, because we’re not Git” doesn’t make sense to me absent arguments that it’s not actually a good name.

Is it worth coordinating a rename with the change in behavior we've talked about (#2802)? We could do it by adding revert with the new behavior and deprecating backout (without changing its behavior).

If you mean making -d/-B/-A mandatory, I think that would be a sensible idea. I’m not sure I’m a fan of the original proposal in the issue.

[joyously]

I reread the help and it still seems like backout is similar to the concept of abandon. It has revset and destination options.
But the abandon help talks about rebasing descendants, and refers to similarity of restore. The help for restore refers to similarity of abandon.
If they are all different, the differences should be more apparent.

[PhilipMetzger]

@PhilipMetzger That's a reasonable assessment based on the OP. Re-reading my OP, I can see how it came across as "This is what is used ingit, so it makes sense to do the same in jj!" – but that wasn't my intention at all.

The reality is, I simply think "revert" is better terminology here, and is what I use in day-to-day parlance when speaking with colleagues, e.g. it feels natural to me to say to someone "Could you please revert yesterday's change?" but appreciate this could be a cultural difference.

Yes, and that presumably stems from Git's dominance since it is the thing you're used to (like when you say you merge a PR/MR, etc). In Mercurial-like systems it is natural to say "backout the Changeset ". See Saplings history for an example.

If it being used in Git is not an argument against it then it neither is one in favor of it. Since Jujutsu actually is something new, some unfamiliarity should be a given for users coming from Git, but that is not a bad thing.

I just think that either previous systems are irrelevant and we shouldn’t talk about them at all, or familiarity with Git can only, all else being equal, be a positive – perhaps a very mild positive, but not a negative

I disagree that it is not a negative, as it gives people the perception that Jujutsu just is another frontend for Git which may seem true now, but won't be in the future. It also carries all the baggage from Git's model with it.

If I thought git revert was a bad name I wouldn’t suggest it, but I think it’s better than hg backout, I can’t think of anything that seems strictly better, and so Git familiarity is just a cherry on top. “Git uses this name, so we shouldn’t, because we’re not Git” doesn’t make sense to me absent arguments that it’s not actually a good name.

I didn't say it was a bad name, it just carries a association which I deem to not favor us in the future. I prefer invert just to get that context away.

Is it worth coordinating a rename with the change in behavior we've talked about (#2802)?

SGTM