Used variable for instantiation differs in Scala 3

[phkorn]

Demo Repository

The following code produces a different outcome when using Scala 3:

import com.softwaremill.macwire.wire

case class Berry(var name: String)
case class Basket(berry: Berry)

object Main extends App {
  val blackberry: Berry = Berry("blackberry")
  val basket: Basket = {
      lazy val raspberry: Berry = Berry("raspberry")
      wire[Basket]
  }
  println(basket.berry.name) // scala 2.13.30 raspberry, scala 3.0.2 blackberry
}

[adamw]

@mbore maybe you have an idea if this is possible to fix?

[djx314]

If understood macwire as scala implicit(get by Context in this position). It's better to throw a compile time Exception.

[arteme]

The problem here -in Scala 3- is not that blackberry is chosen over raspberry, but that raspberry is not considered at all!

If blackberry is removed, the code will fail to compile in Scala 3:

object Main extends App {
  val basket: Basket = {
      lazy val raspberry: Berry = Berry("raspberry")
      wire[Basket] // ERROR: Cannot find a value of type: [Berry]
  }
  println(basket.berry.name)
}