Test case

This demonstrates currently unsoundness when it comes to assignments via setters

Author: odersky

tests/neg-custom-args/captures/refs.scala

@@ -0,0 +1,42 @@
+import java.io.*
+
+class Ref[T](init: T):
+  var x: T = init
+  def setX(x: T): Unit = this.x = x
+
+def usingLogFile[sealed T](op: FileOutputStream^ => T): T =
+  val logFile = FileOutputStream("log")
+  val result = op(logFile)
+  logFile.close()
+  result
+
+type Proc = () => Unit
+def test1 =
+  usingLogFile[Proc]: f => // error
+    () =>
+      f.write(1)
+      ()
+
+def test2 =
+  val r = new Ref[Proc](() => ())
+   usingLogFile[Unit]: f =>
+    r.setX(() => f.write(10))  // should be error
+  r.x() // crash: f is closed at that point
+
+def test3 =
+  val r = new Ref[Proc](() => ())
+   usingLogFile[Unit]: f =>
+    r.x = () => f.write(10)   // should be error
+  r.x() // crash: f is closed at that point
+
+def test4 =
+  var r: Proc = () => ()  // error
+   usingLogFile[Unit]: f =>
+    r = () => f.write(10)
+  r() // crash: f is closed at that point
+
+
+
+
+
+