Scala 3 unnecessarily resolves type aliases in function argument types

[xerial]

object MyMacros {
  def typeNameOf[A: Type](using Quotes): Expr[String] = {
    val name = Type.show[A]
    Expr(name)
  }
}

object Test extends App {
  inline def typeNameOf[A]: String = ${
    MyMacros.typeNameOf[A]
  }

  inline def typeNameOfF1[A](f: A => Unit): String = ${
    MyMacros.typeNameOf[A]
  }

  type MyString = String

  println(typeNameOf[MyString]) 
  // MyString (OK)
  println(typeNameOfF1 { (x: MyString) =>  })   
  // java.lang.String <---------- NG: This should be MyString
  println(typeNameOfF1[MyString] { (x: MyString) =>  })  
  // MyString <--- OK. If the type name is given as type param, the alias is preserved 
  
  println(typeNameOfF1 { (x: Seq[MyString]) => })
  // scala.colleciton.immutable.Seq[MyString]
  prinrln(typeNameOfF1 { (x: (MyString, Int)) => })
  // scala.Tuple2[MyString, scala.Int]
}

Scala 3 (3.1.2) shows inconsistent behavior in resolving type aliases.

[xerial]

It looks like a bug of Scala 3 inline methods. Reported this issue https://github.com/lampepfl/dotty/issues/15304

[xerial]

Related https://github.com/lampepfl/dotty/issues/9421

[xerial]

This problem causes an issue in DI if provider binding with alias type arguments:

type MyString = String

Design.newDesign
  .bind[MyString].toInstance("hello")
  .bind[X].toProvider{ (s: MyString) => println(s) }      /// MISSING_DEPENDENCY String

[xerial]

A workaround is using type tag (@@):

import wvlet.airframe.surface.tag.* 
trait Env

Design.newDesign
  .bind[String @@ Env].toInstance("hello")
  .bind[X].toProvider{ (s: String @@ Env) => println(s) }

Let's close this ticket as Scala 3 might not be fixed to make type resolver lazy.