ClassCastException during REPL execution

[vasilmkd]

Compiler version

3.4.1

Minimized code

It is important to apply each of the definitions/expressions one by one, otherwise the exception is not reproducible.

scala> def g1(acc: Int)(h: (Int, Int) => Int): Int = h(acc, acc)
// def g1(acc: Int)(h: (Int, Int) => Int): Int

scala> def g2(acc: Int)(h: (=> Int, => Int) => Int): Int = h(acc, acc)
// def g2(acc: => Int)(h: (=> Int, => Int) => Int): Int

scala> g2(1)(_ + _)
// java.lang.ClassCastException: class java.lang.Integer cannot be cast to class scala.Function0 (java.lang.Integer is in module
// java.base of loader 'bootstrap'; scala.Function0 is in unnamed module of loader java.net.URLClassLoader @49798e84)
//   at scala.Function2.apply$mcIII$sp(Function2.scala:40)
//   at rs$line$2$.g2(rs$line$2:1)
//   ... 35 elided

Expectation

The result should be 2, instead of a ClassCastException being thrown.

Related IntelliJ IDEA ticket: https://youtrack.jetbrains.com/issue/SCL-22382/ClassNotFoundException-when-running-a-Scala-3-worksheet

[som-snytt]

otherwise the exception is not reproducible.

oh man, hate it when that happens.

[smarter]

Fixed in nightly builds by #19983