Quoted pattern should devirtualize member selections

[nicolasstucki]

The semantics still seem incomplete in this implementation.

Consider:

trait A { def foo: Int }
trait B extends A { def foo: Int = 1 }

val e0: Expr[A] = '{ new B }
val e1: Expr[Int] = '{ $e0.foo }

The quoted expression e1 will not match a pattern like '{ ($x: B).foo }, but it should.

Originally posted by @LPTK in #10531 (comment)

[nicolasstucki]

Test for this issue

import scala.quoted._

trait A { def foo: Int }
class B extends A { def foo: Int = 1 }

inline def test(): Unit = ${ testExpr() }

def testExpr()(using Quotes): Expr[Unit] = {
  val e0: Expr[A] = '{ new B }
  val e1: Expr[Int] = '{ $e0.foo }
  e1 match
    case '{ ($x: B).foo } => '{}
    case _ => quotes.reflect.report.throwError("did not match")
}

def Test = test()