java exception during first attempt to do REPL completion by TAB in sbt console on Scala 3.4.1

[bjornregnell]

steps

Use Scala 3.4.1 and any sbt of version 1.9.8, 1.9.9, 1.10.0.

Start the console and type Seq. and press TAB for completion.

problem

There is this exception when pressing TAB for the first time:

exception caught when loading class module-info: java.lang.AssertionError: assertion failed: attempt to parse java.lang.Object from classfile

expectation

There should not be an exception.

notes

It works fine with Scala 3.3.3.

REPL completion works fine with scala-cli 1.3.1 and Scala 3.4.1.

Discord discussion:
https://discord.com/channels/632150470000902164/632628489719382036/1240625302317830214

[som-snytt]

IDK but scala 3 PR on -experimental says

Besides being a performance issue, this could also lead to a crash if the current package is the empty package, because we could end up forcing the magic module-info.class that Java modules place there. For some reason, this appear to only happen when building with sbt, hence the additional scripted test.

[bjornregnell]

@som-snytt Can you also reproduce this on your machine? (So that I can relax and not worry about if it's not just my box playing tricks...)

[bjornregnell]

Cross-posted here: scala/scala3#20421
If it is verified that the root cause is not sbt then this should be closed.