Merge pull request #12615 from dotty-staging/fix-12583

Fix implicit ValueOf synthesis

Author: nicolasstucki

compiler/src/dotty/tools/dotc/typer/Synthesizer.scala

@@ -162,7 +162,7 @@ class Synthesizer(typer: Typer)(using @constructorOnly c: Context):
       New(defn.ValueOfClass.typeRef.appliedTo(t.tpe), t :: Nil).withSpan(span)
     formal.argInfos match
       case arg :: Nil =>
-        fullyDefinedType(arg.dealias, "ValueOf argument", span).normalized match
+        fullyDefinedType(arg, "ValueOf argument", span).normalized.dealias match
           case ConstantType(c: Constant) =>
             success(Literal(c))
           case tp: TypeRef if tp.isRef(defn.UnitClass) =>

tests/pos/i12583.scala

@@ -0,0 +1,5 @@
+case class Wrapper[A <: Singleton](a: A)(using ValueOf[A])
+
+def test[A <: Singleton](blabla: Wrapper[A]): Unit = ()
+
+val _ = test(Wrapper("yo"))