Implement operator-is for interfaces' supertypes and String's supertypes. Also, improve stack trace…

dart/tests/corelib/src/IsOperatorBasicTypesTest.dart

Index: dart/tests/corelib/src/IsOperatorBasicTypesTest.dart
diff --git a/dart/tests/corelib/src/IsOperatorBasicTypesTest.dart b/dart/tests/corelib/src/IsOperatorBasicTypesTest.dart
new file mode 100644
index 0000000000000000000000000000000000000000..285c79346d539484f58ab0d8816d75ad7d7eeae3
--- /dev/null
+++ b/dart/tests/corelib/src/IsOperatorBasicTypesTest.dart
@@ -0,0 +1,71 @@
+// Copyright (c) 2012, 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 the "is" type test operator.
+
+check(args) {
+  var list = args[0];
+  var string = args[1];
+  var nullObject = args[2];
+
+  Expect.isTrue(list is Object);
+  Expect.isTrue(list is List);
+  Expect.isTrue(list is Collection);
+  Expect.isTrue(list is Iterable);
+  Expect.isFalse(list is Comparable);
+  Expect.isFalse(list is Hashable);
+  Expect.isFalse(list is Pattern);
+  Expect.isFalse(list is String);
+
+  Expect.isFalse(list is !List);
+  Expect.isFalse(list is !Collection);
+  Expect.isFalse(list is !Iterable);
+  Expect.isTrue(list is !Comparable);
+  Expect.isTrue(list is !Hashable);
+  Expect.isTrue(list is !Pattern);
+  Expect.isTrue(list is !String);
+
+  Expect.isTrue(string is Object);
+  Expect.isFalse(string is List);
+  Expect.isFalse(string is Collection);
+  Expect.isFalse(string is Iterable);
+  Expect.isTrue(string is Comparable);
+  Expect.isTrue(string is Hashable);
+  Expect.isTrue(string is Pattern);
+  Expect.isTrue(string is String);
+
+  Expect.isTrue(string is !List);
+  Expect.isTrue(string is !Collection);
+  Expect.isTrue(string is !Iterable);
+  Expect.isFalse(string is !Comparable);
+  Expect.isFalse(string is !Hashable);
+  Expect.isFalse(string is !Pattern);
+  Expect.isFalse(string is !String);
+
+  Expect.isTrue(nullObject is Object);
+  Expect.isFalse(nullObject is List);
+  Expect.isFalse(nullObject is Collection);
+  Expect.isFalse(nullObject is Iterable);
+  Expect.isFalse(nullObject is Comparable);
+  Expect.isFalse(nullObject is Hashable);
+  Expect.isFalse(nullObject is Pattern);
+  Expect.isFalse(nullObject is String);
+
+  Expect.isTrue(nullObject is !List);
+  Expect.isTrue(nullObject is !Collection);
+  Expect.isTrue(nullObject is !Iterable);
+  Expect.isTrue(nullObject is !Comparable);
+  Expect.isTrue(nullObject is !Hashable);
+  Expect.isTrue(nullObject is !Pattern);
+  Expect.isTrue(nullObject is !String);
+}
+
+main() {
+  // Try to make it hard for an optimizing compiler to inline the
+  // tests.
+  check([[], 'string', null]);
+
+  // Try to make it even harder.
+  var string = new String.fromCharCodes([new Date.now().year % 100 + 1]);
+  check([string.charCodes(), string, null]);
+}