More test cases

Author: odersky

tests/neg/singletonOrs.scala

@@ -4,3 +4,31 @@ object Test {
    def c: 1 | 2 = 1
    def d: 1 = a // error
 }
+
+// Following examples are from issue #1551
+object Test2 {
+  type ABC = 'A' | 'B' | 'C'
+  type A2F = ABC | 'D' | 'E' | 'F'
+
+  def foo(x: A2F) = ()
+  foo('F') // ok
+  foo('G') // error
+}
+
+object Get2As1 {
+  class OrIntroFn[T, U, TU >: T|U]{
+    type V = TU
+    def tuToV(): (TU => V) = p => p
+  }
+  class Or11X[X] extends OrIntroFn[1&1, X, (1&1|X)]{
+    def get2as11X:V = tuToV()(2)  // error
+  }
+  class Or11Nothing extends Or11X[Nothing]
+  def get2as1:1 = new Or11Nothing().get2as11X // error
+
+  def main(a:Array[String]) = {
+    println(get2as1) // prints 2
+    val one:1 = get2as1
+    println(one) // prints 1
+  }
+}

tests/pos/single-unions.scala

@@ -2,4 +2,14 @@ object A {
   val x1: 3 | 4 = 3
   val x2: 3 | 4 = 4
   val x3: 3 | 4 = if (???) 3 else 4
-}
+}
+
+// The following example is from issue #1551
+object Test1 {
+  sealed trait Fence[+T, +S]
+  case object End extends Fence[Nothing, Nothing]
+  case class Post[+T, +S](value: T, next: Panel[T, S] | End.type) extends Fence[T, S]
+  case class Panel[+T, +S](value: S, next: Post[T, S]) extends Fence[T, S]
+
+  val fence = Post(1, Panel("two", Post(3, End)))
+}