Add more tests

tests/explicit-nulls/flexible-unpickle/Flexible_2.scala

@@ -1,6 +1,6 @@
 import unsafeNulls.Foo.*
 import unsafeNulls.Unsafe_1
-import unsafeNulls.{A, B, C}
+import unsafeNulls.{A, B, C, F, G, H, I, J, L, M}
 import scala.reflect.Selectable.reflectiveSelectable
 
 class Inherit_1 extends Unsafe_1 {
@@ -31,6 +31,9 @@ class Inherit_4 extends Unsafe_1 {
 
 case class cc()
 
+class K(val b: String) extends J(b) {
+}
+
 @main
 def Flexible_2() =
   val s2: String | Null = "foo"
@@ -66,3 +69,31 @@ def Flexible_2() =
   val constructorTest = new Unsafe_1(null)
   val member: String = constructorTest.member
   constructorTest.member = null
+
+  bar match {
+    case str @ null: String => ()
+    case other => ()
+  }
+
+  val f = new F(null, G(12))
+  val F(x, y) = f
+
+  val g: (List[F] | String | List[Int]) = F.many
+  F.many = null :: null :: Nil
+  F.many = null
+
+  val h: H { val s: String } = new H { override val s: String = "foo" }
+
+  val jBox: I[J] = new I(new J(null))
+  val kBox: I[K] = new I(new K("foo"))
+
+  val box: I[J] = kBox
+
+  val jBox2: L[J] = new L[J](j => ())
+  val kBox2: L[K] = new L[K](k => ())
+
+  val box2: L[K] = jBox2
+  val box3: I[J | Null] = box
+
+  val m: String = M.test(null)
+

tests/explicit-nulls/flexible-unpickle/Unsafe_1.scala

@@ -35,6 +35,7 @@ trait C {
   var stringC: String
 }
 
+
 object Foo {
   extension (c: C)
     def reverse: String = c.stringC.reverse
@@ -45,4 +46,30 @@ object Foo {
   var singleton: bar.type = bar
   var intersection: A & B = ???
   var union: A | B = ???
-}
+}
+
+class F(var x: String, var y: G)
+
+class G(var z: Int)
+
+object F {
+  def unapply(f: F): (String, G) = (f.x, f.y)
+  var many: (List[F] | String | List[Int]) = null
+}
+
+class H {
+  val s: String = null
+}
+
+class I[+A](val value: A)
+
+class J(val a: String) {}
+
+class L[-A](f: A => Unit)
+
+class M {}
+
+object M {
+  def test(input: => String): String = "foo " + input
+}
+