Support Scala 3.3.0-RC1

[gvolpe]

Any chances of publishing a milestone or RC for this Scala version? A lot of folks are interested in the new -Wunused:imports flag :)

scala/scala3#16157

[ghik]

Hi, can you make a PR?
https://github.com/ghik/zerowaste#how-to-submit-a-pr-with-a-new-scala-version

[gvolpe]

Happy to do so! Expect one later this evening :)

[ghik]

Fixed in 0.2.3

[kubukoz]

As a fellow plugin author, I'd like to suggest backpublishing (publishing an artifact under an existing version) - it can be kinda annoying when the plugin keeps getting updates that don't change anything for existing Scala versions, especially if you're trying to support Scala milestones.

I made this: https://github.com/polyvariant/better-tostring/blob/main/project/BackpublishPlugin.scala - for projects publishing with sbt-typelevel, but maybe it can easily be modified to work for your build as well. The downside is that you make these releases locally and not from CI (that should be possible as well, though)

[ghik]

@kubukoz yeah, I used to backpublish silencer but it became sufficiently annoying to publish locally that I dropped it. Maybe I'll look into it again, thanks for the reference.

[kyri-petrou]

Out of curiosity, are there any additional checks that this plugin does in Scala versions 3.3.x and above, as opposed to using the new -Wvalue-discard compiler flag?

[gvolpe]

@kyri-petrou I can only speak as a user of this plugin, and can confirm -Wvalue-discard doesn't catch discarded IO values, whereas zerowaste does: https://gist.github.com/gvolpe/088f6d1a1a8071304b6ae2db444d687c

You can see this program fails to compile, but if you comment out the using plugin line, it'll compile without issues. Unrelated, but it looks like a lot of these new flags are still quite buggy --- e.g. the -Wunused:imports flag gives some false-positives.

[kyri-petrou]

@gvolpe that's quite interesting.. For some reason I can't get the flag to work at all when using scala-cli. In any way, I'll stick with zerowaste plugin until the compiler flags are in a more mature state 👍