`ExprMap` cannot map over call sites taking by name parameters

[rmgk]

Compiler version

3.1.2, Scala 3.2.0-RC1-bin-20220517-e5abec0-NIGHTLY

Minimized code

Boilerplate to just do an empty transform using ExpMap

import scala.quoted.*

inline def mac[T](inline expr: T): T =
  ${ impl('expr) }

class MyMap() extends ExprMap {
  override def transform[T](e: Expr[T])(using Type[T])(using q: Quotes): Expr[T] =
    transformChildren(e)
}

def impl[T: Type](expr: Expr[T])(using quotes: Quotes): Expr[T] = {
  MyMap().transform(expr)
}

Then call with something that takes a by name parameter, for example mac(None.getOrElse(3))

Output

java.lang.Exception: Expr cast exception: 3
of type: 3
did not conform to type:  => scala.Int
	at scala.quoted.runtime.impl.QuotesImpl.asExprOf(QuotesImpl.scala:71)
	at scala.quoted.runtime.impl.QuotesImpl$reflect$TreeMethods$.asExprOf(QuotesImpl.scala:114)
	at scala.quoted.runtime.impl.QuotesImpl$reflect$TreeMethods$.asExprOf(QuotesImpl.scala:113)
	at scala.quoted.ExprMap.transformChildren(ExprMap.scala:150)
	at scala.quoted.ExprMap.transformChildren$(ExprMap.scala:3)

Expectation

Should return the unmodified expression

[nicolasstucki]

We probably need to strip the ByNameType types here https://github.com/lampepfl/dotty/blob/main/library/src/scala/quoted/ExprMap.scala#L51.