Merge pull request #984 from joroKr21/hkt-id-selector

Add missing asInstanceOf call

core/src/main/scala/shapeless/generic.scala

@@ -941,7 +941,7 @@ class GenericMacros(val c: whitebox.Context) extends CaseClassMacros {
     val (p, ts) = ctorDtor.binding
     val to = cq"$p => ${mkHListValue(ts)}.asInstanceOf[$repr]"
     val (rp, rts) = ctorDtor.reprBinding
-    val from = cq"$rp => ${ctorDtor.construct(rts)}"
+    val from = cq"$rp => ${ctorDtor.construct(rts)}.asInstanceOf[$tpe]"
     q"$generic.instance[$tpe, $repr]({ case $to }, { case $from })"
   }
 

core/src/test/scala_2.13+/shapeless/LabelledGenericTests213.scala

@@ -0,0 +1,22 @@
+package shapeless
+
+import org.junit.Assert._
+import org.junit.Test
+import shapeless.ops.record.Selector
+
+class LabelledGenericTests213 {
+  import LabelledGenericTests213._
+
+  @Test
+  def testSelectorWithHkt(): Unit = {
+    assertEquals(0, new Func[Hkt[Option]].select("foo"))
+    assertEquals(0, new Func[Hkt[Id]].select("foo"))
+  }
+}
+
+object LabelledGenericTests213 {
+  case class Hkt[F[_]](foo: F[String])
+  class Func[T] {
+    def select[R <: HList](k: Witness)(implicit gen: LabelledGeneric.Aux[T, R], selector: Selector[R, k.T]) = 0
+  }
+}