Missing invalidation with 2.13.12 (zinc / compiler bridge)

[lrytz]

Missing invalidation / recompilation in zinc with 2.13.12, discovered while working on https://github.com/scala/scala/pull/10554.

• Check out this branch https://github.com/lrytz/scala/tree/missing-invalidation
• Run set sbtTest/scriptedBufferLog := false and set ThisBuild / Compile / packageDoc / publishArtifact := false in sbt
• Run sbtTest/scripted source-dependencies/empty-package

Output for reference: https://gist.github.com/lrytz/61930adc6ed4f7d0648bbc1abf3b0bef

I tested this in a small sbt project and I can reproduce the issue. Notes

• It happens with both sbt 1.9.6 and 1.9.4. The former uses the binary bridge from Scala 2.13.12, the latter compiles the bridge from source.
• ~It doesn't happend with Scala 2.13.11.~ That was wrong testing from my side. Older 2.13 versions are the same, also 2.12.18.

I also tried reproducing the issue in the scripted test in the zinc repository, but didn't manage, not sure why. Output of running the test in zinc: https://gist.github.com/lrytz/e42076ecadc49c770465f97c12a0602b

[lrytz]

Moved to https://github.com/sbt/zinc/issues/1268