Make MiMa aware of @akka.annotation.ApiMayChange / @akka.annotation.InternalApi

[ktoso]

We introduced a few annotations to mark that a given type should not matter when checking bin-compat:

• @ApiMayChange - API still not quite stable, will change
• @InternalAPI - internal API, can change however it wants to
• @DoNotInherit - no one except the same library which provides this class should extend this class

Full types: https://github.com/akka/akka/pull/22110/files
Example usage: akka/akka#22109

MiMa could check if a type has annotations and if the name matches these then it can ignore warnings about a given type or method.

[dwijnand]

I think it would be best to provide such a feature by enhancing MiMa's ProblemFilters:

https://github.com/typesafehub/migration-manager/blob/0.1.13/core/src/main/scala/com/typesafe/tools/mima/core/Filters.scala

[ktoso]

ExcludeAnythingAnnotatedWith?

[dwijnand]

Yeah. (maybe more simply ExcludeAnnotatedWith or ExcludeWithAnnotation)

[ktoso]

Yeah, would be very cool :) I may hack on this... Would save us a lot of explaining to contributors who touch these classes.

[dwijnand]

This is midly related to #53

[dwijnand]

I'm thinking we can do this by name. Probably best to stick to fully qualified name. But then I just realised it can a user-definable list of names, e.g. Scala 3's new @scala.annotation.experimental annotation, which the Scala 3 build can add to its build (e.g. scala/scala3#11721)

[SethTisue]

Note that #647 only implements this for Scala 3, not for Scala 2.

(Because anything involving unpickling must be separately implemented, since Scala 3's pickle format is completely different, being TASTy-based.)