Support runtime check of function types.

tests/language/function_subtype_cast1_test.dart

Index: tests/language/function_subtype_cast1_test.dart
diff --git a/tests/language/function_subtype_cast1_test.dart b/tests/language/function_subtype_cast1_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..74b694a6a9a294b766ff4939a00bd2fe0cc159fa
--- /dev/null
+++ b/tests/language/function_subtype_cast1_test.dart
@@ -0,0 +1,32 @@
+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+// Dart test program for constructors and initializers.
+
+// Check function subtyping casts.
+
+import 'package:expect/expect.dart';
+
+typedef void Foo<T>(T t);
+typedef void Bar(int i);
+
+class Class<T> {
+  void bar(T i) {}
+}
+
+void main() {
+  Expect.isNotNull(new Class().bar as Foo);
+  Expect.isNotNull(new Class().bar as Foo<bool>);
+  Expect.isNotNull(new Class().bar as Foo<int>);
+  Expect.isNotNull(new Class().bar as Bar);
+
+  Expect.isNotNull(new Class<int>().bar as Foo);
+  Expect.throws(() => new Class<int>().bar as Foo<bool>, (e) => true);
+  Expect.isNotNull(new Class<int>().bar as Foo<int>);
+  Expect.isNotNull(new Class<int>().bar as Bar);
+
+  Expect.isNotNull(new Class<bool>().bar as Foo);
+  Expect.isNotNull(new Class<bool>().bar as Foo<bool>);
+  Expect.throws(() => new Class<bool>().bar as Foo<int>, (e) => true);
+  Expect.throws(() => new Class<bool>().bar as Bar, (e) => true);
+}