Add support for Kotlin 2.x

[barbulescu]

What's changed?

What's your motivation?

• Closes https://github.com/openrewrite/rewrite/pull/5575

Anything in particular you'd like reviewers to focus on?

Anyone you would like to review specifically?

Have you considered any alternatives or workarounds?

Any additional context

Checklist

• [ ] I've added unit tests to cover both positive and negative cases
• [ ] I've read and applied the recipe conventions and best practices
• [ ] I've used the IntelliJ IDEA auto-formatter on affected files

[timtebeek]

Gradle 9 should be interesting, as that now requires Kotlin 2.1. All the more appreciative of your efforts here!

[timtebeek]

Linking the relevant thread in the Kotlin lang Slack here as well. Let us know if you could use more help!

[e5l]

Hey @barbulescu, we're looking forward to having Kotlin 2.x support 🙂.

Could you please let me know if you have any issues or require assistance?

[timtebeek]

Thanks for your interest @e5l ; there's also this parallel alternative approach, where we're exploring a separate Kotlin 2 parser which more closely matches the model of the underlying compiler:

• https://github.com/openrewrite/rewrite/pull/5963

It's expected that we can take learnings from the work done here, but might have that flow into the new Kotlin 2 parser, such that we can support these two in parallel rather than a hard switch over.