add test set for exhaustivity and redundancy check

1 files changed, 58 insertions, 0 deletions

diff --git a/tests/patmat/exhausting.scala b/tests/patmat/exhausting.scala
new file mode 100644
index 000000000..03e8198dd
--- /dev/null
+++ b/tests/patmat/exhausting.scala
@@ -0,0 +1,58 @@
+object Test {
+  sealed abstract class Foo[T]
+  case object Bar1 extends Foo[Int]
+  case object Bar2 extends Foo[String]
+  case object Bar3 extends Foo[Any]
+
+  def ex1[T](xs: List[T]) = xs match {
+    case ys: List[_]  => "ok"
+  }
+  def ex2[T](xx: (Foo[T], Foo[T])) = xx match {
+    case (Bar1, Bar1) => ()
+    case (_, Bar1) => ()
+    case (_, Bar3) => ()
+    case (_, Bar2) => ()
+  }
+  def ex3[T](xx: (Foo[T], Foo[T])) = xx match {
+    case (_: Foo[_], _: Foo[_]) => ()
+  }
+
+  // fails for: ::(_, Nil), ::(_, ::(_, ::(_, _))), ...
+  def fail1[T](xs: List[T]) = xs match {
+    case Nil            => "ok"
+    case x :: y :: Nil  => "ok"
+  }
+
+  // fails for: Nil
+  def fail2[T](xs: List[T]) = xs match {
+    case _ :: _ => "ok"
+  }
+
+  // fails for: ::(<not in (2, 1)>, _)
+  def fail3a(xs: List[Int]) = xs match {
+    case 1 :: _ =>
+    case 2 :: _ =>
+    case Nil =>
+  }
+
+  // fails for: Bar3
+  def fail3[T](x: Foo[T]) = x match {
+    case Bar1   => "ok"
+    case Bar2   => "ok"
+  }
+  // fails for: (Bar2, Bar2)
+  def fail4[T <: AnyRef](xx: (Foo[T], Foo[T])) = xx match {
+    case (Bar1, Bar1) => ()
+    case (Bar2, Bar3) => ()
+    case (Bar3, _) => ()
+  }
+  // fails for: (Bar1, Bar2)
+  // fails for: (Bar1, Bar3)
+  // fails for: (Bar2, Bar1)
+  // fails for: (Bar2, Bar2)
+  def fail5[T](xx: (Foo[T], Foo[T])) = xx match {
+    case (Bar1, Bar1) => ()
+    case (Bar2, Bar3) => ()
+    case (Bar3, _) => ()
+  }
+}