InjectedController trait not working with scala 3 about playframework HOT 9 OPEN

Pretty sure I nailed it down:
When decompiling HomeController.class (using javap -v) the method signature for setControllerComponents is different for Scala 2.13 and Scala 3.

Scala 2.13:

  public void setControllerComponents(play.api.mvc.ControllerComponents);
    descriptor: (Lplay/api/mvc/ControllerComponents;)V
    flags: (0x0001) ACC_PUBLIC

Scala 3:

  public void setControllerComponents(play.api.mvc.ControllerComponents);
    descriptor: (Lplay/api/mvc/ControllerComponents;)V
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC

So you see Scala 3 marks the method as synthetic bridge method (ACC_BRIDGE and ACC_SYNTHETIC).

Guice however ignores such methods:
https://github.com/google/guice/blob/f095cad8aa7b59abafacc4d4461ddfc77be83667/core/src/com/google/inject/spi/InjectionPoint.java#L819-L841

Need to find a workaround...

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So according to scala/scala3#19270 (comment) this is a problem in the Scala 3 compiler. Let's leave the things how they are currently and let's hope they fix it with Scala 3.3.3 (3.3.2 is in RC phase already, so no chance anymore)

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Thanks for the quick feedback and for your work on Play! 👏🏻

Seems pretty low level stuff (scala compiler...), I don't know why they changed this in scala 3.
Hope that, as you said, you can find a workaround.

One can still use AbstractController instead of InjectedController but if there's a way to make it work that would be better.

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If there's interest I would open a doc pull-request to add a short warning

@aumann Yes sure, please go for it, thanks!

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Can confirm, taking a look already. Thanks a lot for the report!

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This is definitely regression / breaking change in Scala 3 compiler

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So I tried lots of stuff, but couldn't make it work, and at this point I also believe this is a bug in the Scala 3 compiler, but I am not 100% sure, so I leave the judgment to the experts:

• scala/scala3#19270

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Thanks for the follow up!
Let's wait for the fix.

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Should this be added to the migration notes? It hit us in production (we only used the InjectedController in one rarely visited spot 🙈 ), and might hit others migrating to play 2.9/3.0.

If there's interest I would open a doc pull-request to add a short warning to: https://www.playframework.com/documentation/2.9.x/Scala3Migration

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