Add test case

Author: odersky

tests/pos/i23611.scala

@@ -0,0 +1,26 @@
+import java.io.{File, IOException}
+import java.net.URI
+import java.nio.file.{Path, Paths}
+import scala.reflect.ClassTag
+
+trait FileConnectors {
+  def listPath(path: => Path): ZStream[Any, IOException, Path]
+
+  final def listFile(file: => File): ZStream[Any, IOException, File] =
+    for {
+      path <- null.asInstanceOf[ZStream[Any, IOException, Path]]
+      r    <- listPath(path).mapZIO(a => ZIO.attempt(a.toFile).refineToOrDie)
+    } yield r
+}
+
+sealed trait ZIO[-R, +E, +A]
+extension [R, E <: Throwable, A](self: ZIO[R, E, A])
+  def refineToOrDie[E1 <: E: ClassTag]: ZIO[R, E1, A] = ???
+
+object ZIO:
+  def attempt[A](code: => A): ZIO[Any, Throwable, A] = ???
+
+sealed trait ZStream[-R, +E, +A]:
+  def map[B](f: A => B): ZStream[R, E, B] = ???
+  def flatMap[R1 <: R, E1 >: E, B](f: A => ZStream[R1, E1, B]): ZStream[R1, E1, B]
+  def mapZIO[R1 <: R, E1 >: E, A1](f: A => ZIO[R1, E1, A1]): ZStream[R1, E1, A1]