Add comparison operators to Date class.

tests/corelib/date_time6_test.dart

Index: tests/corelib/date_time6_test.dart
diff --git a/tests/corelib/date_time6_test.dart b/tests/corelib/date_time6_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..d99a634b3dfcaa3195540c203f4a8e4c38c3db90
--- /dev/null
+++ b/tests/corelib/date_time6_test.dart
@@ -0,0 +1,29 @@
+// 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.
+
+// Test Date comparison operators.
+
+main() {
+  var d = new Date.fromEpoch(0, const TimeZone.utc());
+  var d2 = new Date.fromEpoch(1, const TimeZone.utc());
+  Expect.isTrue(d < d2);
+  Expect.isTrue(d <= d2);
+  Expect.isTrue(d2 > d);
+  Expect.isTrue(d2 >= d);
+  Expect.isFalse(d2 < d);
+  Expect.isFalse(d2 <= d);
+  Expect.isFalse(d > d2);
+  Expect.isFalse(d >= d2);
+
+  d = new Date.fromEpoch(-1, const TimeZone.utc());
+  d2 = new Date.fromEpoch(0, const TimeZone.utc());
+  Expect.isTrue(d < d2);
+  Expect.isTrue(d <= d2);
+  Expect.isTrue(d2 > d);
+  Expect.isTrue(d2 >= d);
+  Expect.isFalse(d2 < d);
+  Expect.isFalse(d2 <= d);
+  Expect.isFalse(d > d2);
+  Expect.isFalse(d >= d2);
+}