WIP: Scala3 remaining modules

[jtjeferreira]

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• Have you referenced any issues you're fixing using commit message keywords?
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• Have you added tests for any changed functionality?

Helpful things

Fixes

Fixes #11260

Purpose

Scala 3

Background Context

Why did you take this approach?

References

Are there any relevant issues / PRs / mailing lists discussions?

[mkurz]

@jtjeferreira Same here... Thanks!

[jtjeferreira]

@jtjeferreira Same here... Thanks!

Fixed, but this is still WIP because there are some tests failing.
I think the failures are related to using NettyBackend instead of AkkaHttp. Feel free to have a look

[mkurz]

@jtjeferreira Can you please resolve the conflicts once more, obrigado!

[jtjeferreira]

@jtjeferreira Can you please resolve the conflicts once more, obrigado!

Will do after #11550 is merged

[mkurz]

@jtjeferreira I wanted to take quick a look at this, so I rebased myself and resolved the conflicts.

[mkurz]

Wow. It's green 😉 Not perfect yet however, but very very nice... I will provide more details what I have done here the next days, too late here now...

[jtjeferreira]

Wow. It's green 😉 Not perfect yet however, but very very nice... I will provide more details what I have done here the next days, too late here now...

Thanks for pushing this to the finish line.

Regarding b2f7a71 (#11551) and the java.lang.VerifyError: Bad type on operand stack error, will you open an issue in dotty? That looks really scary...

[mkurz]

Thanks for pushing this to the finish line.

It's not completely done, there are some things I am not yet happy with. I will give this PR a pause for a couple of days since I have other stuff to do as well. But IMHO it's a huge step forward, there is nothing really blocking and everything that needs to be done is pretty clear.

Regarding b2f7a71 (#11551) and the java.lang.VerifyError: Bad type on operand stack error, will you open an issue in dotty? That looks really scary...

Yeah I was thinking about that, I just was too tired yesterday, also have to come up with an isolated reproducer.

[mkurz]

We also want to have a Scala 3 migration page in the docs for migration steps we already know about.

[mkurz]

Thanks for pushing this to the finish line.

Oh and @jtjeferreira: Thank you!

[mkurz]

Started to split this PR into multiple ones, starting with #11698

[mkurz]

@jtjeferreira like for #11550, thanks! This has been incorporated into the main branch via various pull requests: https://github.com/playframework/playframework/issues?q=label%3Ascala3+is%3Aclosed

Yesterday I tagged Play 2.9.0-M3 which now publishes Scala 3 artifacts. Everyone is welcome to try it and give feedback. You can also get started with a seed project by using sbt new playframework/play-scala-seed.g8 --branch 2.9.x