[unstable option] required_version

[scampi]

Tracking issue for required_version

[reynoldsbd]

Would it make sense for required_version to support SemVer semantics similar to Cargo dependencies? This would make it easier to use in cases where CI agents are updated automatically.

For instance, if somebody sets required_version = "1.4.36" but their CI agent is updated separately with a newer patch-release such as 1.4.37, currently their CI build would fail.

[tseli0s]

Why is this not stabilized yet?

[calebcartwright]

Why is this not stabilized yet?

#5365
#5367

[boozook]

There should be semver match instead of just eq, I suppose.

[Awayume]

There should be semver match instead of just eq, I suppose.

I think so too.

[wesleymatosdev]

There should be semver match instead of just eq, I suppose.

Hey guys, willing to help. Should I open a PR to it?

[ytmimi]

@ologbonowiwi thanks for offering to help. Before submitting a PR could you open an issue describing what you're planning to implement. I think it might be useful to discuss the approach before jumping in and working on this.

[wesleymatosdev]

#6063 opened @ytmimi. Can you check if it makes sense?

[wesleymatosdev]

And regarding the conditions:

• Is the default value correct ?
• The design and implementation of the option are sound and clean.
• The option is well tested, both in unit tests and, optimally, in real usage.
• There is no open bug about the option that prevents its use. (I've checked this one, no bugs open)

Which of them still needs to be worked on?

[wesleymatosdev]

There should be semver match instead of just eq, I suppose.

I think so too.

Now we have semver match

rustfmt/src/config/mod.rs

Line 305 in c6c8159

if !check_semver_version(&required_version, version) {

Can someone help me out on drafting next steps to make this stable?

required_version now is well tested, I added a bunch of tests to make sure it matches semver spec. You can check the whole discussion/implementation on #6066.
TL;DR the only missing thing from semver spec is pre-release versions. https://github.com/dtolnay/semver does not use it, but if we decide here it's needed, I can make a contribution there to implement so we don't need to do hacky the support on this codebase.

I assume we need to review design and implementation to check if it's sound and clean. Feel free to comment on #6066 if you see anything that could be fixed, and I can create a PR.

Besides that, probably handle default value and and tests for it, afterward we should be ready to make this field stable. I'd love to hear your thoughts on it. cc: @ytmimi

[ytmimi]

I'd say we're still a ways away from stabilizing this option. We'll want to get feedback on real world usage. The semver change has only recently been merged, but it's not been released to nightly yet. That'll happen the next time we sync rustfmt with rust-lang/rust.