Added logic and tests for unchecked refinements.

3 files changed, 41 insertions, 0 deletions

diff --git a/test/files/neg/unchecked-refinement.check b/test/files/neg/unchecked-refinement.check
new file mode 100644
index 0000000000..d81517464f
--- /dev/null
+++ b/test/files/neg/unchecked-refinement.check
@@ -0,0 +1,13 @@
+unchecked-refinement.scala:17: error: abstract type U in type pattern Foo[U,U,V] is unchecked since it is eliminated by erasure
+    /*   warn */ case _: Foo[U, U, V] if b       => ()
+                         ^
+unchecked-refinement.scala:19: error: non-variable type argument Any in type pattern Foo[Any,U,V] is unchecked since it is eliminated by erasure
+    /*   warn */ case _: Foo[Any, U, V] if b     => ()
+                         ^
+unchecked-refinement.scala:23: error: a pattern match on a refinement type is unchecked
+    /* nowarn - todo */ case x: AnyRef { def bippy: Int } if b => x.bippy  // this could/should do an instance check and not warn
+                                ^
+unchecked-refinement.scala:24: error: a pattern match on a refinement type is unchecked
+    /* nowarn - todo */ case x: AnyRef { def size: Int } if b  => x.size   // this could/should do a static conformance test and not warn
+                                ^
+four errors found
diff --git a/test/files/neg/unchecked-refinement.flags b/test/files/neg/unchecked-refinement.flags
new file mode 100644
index 0000000000..85d8eb2ba2
--- /dev/null
+++ b/test/files/neg/unchecked-refinement.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
diff --git a/test/files/neg/unchecked-refinement.scala b/test/files/neg/unchecked-refinement.scala
new file mode 100644
index 0000000000..79ed7f13c1
--- /dev/null
+++ b/test/files/neg/unchecked-refinement.scala
@@ -0,0 +1,27 @@
+// a.scala
+// Thu Sep 27 09:42:16 PDT 2012
+
+trait Bar[-T1, T2, +T3] { }
+trait Foo[-T1, T2, +T3] extends Bar[T1, T2, T3]
+
+class A {
+  var b = true
+
+  def f1(x: Foo[Int, Int, Int]) = x match {
+    /* nowarn */ case _: Foo[Nothing, Int, Any] => true
+  }
+  def f2[T, U, V](x: Foo[T, U, V]) = x match {
+    /* nowarn */ case _: Foo[Nothing, U, Any] => true
+  }
+  def f3[T, U, V](x: Foo[T, U, V]) = x match {
+    /*   warn */ case _: Foo[U, U, V] if b       => ()
+    /* nowarn */ case _: Foo[Nothing, U, V] if b => ()
+    /*   warn */ case _: Foo[Any, U, V] if b     => ()
+  }
+
+  def f4(xs: List[Int]) = xs match {
+    /* nowarn - todo */ case x: AnyRef { def bippy: Int } if b => x.bippy  // this could/should do an instance check and not warn
+    /* nowarn - todo */ case x: AnyRef { def size: Int } if b  => x.size   // this could/should do a static conformance test and not warn
+    /* nowarn */ case x: ((AnyRef { def size: Int }) @unchecked) if b  => x.size
+  }
+}