Merge pull request #11028 from dotty-staging/fix-#9296

Add regression test

Author: nicolasstucki

tests/pos-macros/i9296/Macros_1.scala

@@ -0,0 +1,28 @@
+package a
+
+import scala.quoted._
+import scala.concurrent._
+
+object M {
+
+  inline def resolveInMacros[F[_],T](f: Future[T]):Conversion[Future[T],F[T]] =
+     ${ resolveInMacrosImpl[F,T]('f) }
+
+  def resolveInMacrosImpl[F[_]:Type,T:Type](f:Expr[Future[T]])(using qctx:Quotes):Expr[
+                                                      Conversion[Future[T],F[T]]]={
+     import quotes.reflect._
+     val conversion = TypeIdent(Symbol.classSymbol("scala.Conversion")).tpe
+     val inFuture = f.asTerm.tpe.widen
+     val tType = TypeRepr.of[T]
+     val fType = TypeRepr.of[F]
+     val inCB = fType.appliedTo(tType).simplified
+     val taConversion = conversion.appliedTo(List(inFuture, inCB))
+     Implicits.search(taConversion) match
+       case implSuccess: ImplicitSearchSuccess =>
+               implSuccess.tree.asExpr.asInstanceOf[Expr[Conversion[Future[T],F[T]]]]
+       case implFailure: ImplicitSearchFailure =>
+               println(s"searchFailure: ${implFailure.explanation}")
+               throw new RuntimeException("implicit search failed")
+  }
+
+}

tests/pos-macros/i9296/Test_2.scala

@@ -0,0 +1,19 @@
+package a
+
+import scala.language.implicitConversions
+import scala.concurrent._
+
+trait CB[T]
+
+given myConversion[T]: Conversion[Future[T],CB[T]] = (ft => ???)
+
+object O {
+
+  def main(argvs: Array[String]): Unit = {
+    val p = Promise[Int]()
+    //val cbp = summon[Conversion[Future[Int],CB[Int]]] //works
+    val cbp = M.resolveInMacros[CB,Int](p.future)
+    val x = cbp(p.future)
+  }
+
+}