Add corelib tests

test/codegen/corelib/reg_exp5_test.dart

Index: test/codegen/corelib/reg_exp5_test.dart
diff --git a/test/codegen/corelib/reg_exp5_test.dart b/test/codegen/corelib/reg_exp5_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..f67cd6d5941cc80e2a3624e35032b5a67430dc09
--- /dev/null
+++ b/test/codegen/corelib/reg_exp5_test.dart
@@ -0,0 +1,25 @@
+// Copyright (c) 2011, 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 for testing regular expressions in Dart.
+
+import "package:expect/expect.dart";
+
+main() {
+  String str = "";
+  try {
+    RegExp ex = new RegExp(str);
+  } catch (e) {
+    if (!(e is ArgumentError)) {
+      Expect.fail("Expected: ArgumentError got: ${e}");
+    }
+  }
+  Expect.isFalse(new RegExp(r"^\w+$").hasMatch(str));
+  Match fm = new RegExp(r"^\w+$").firstMatch(str);
+  Expect.equals(null, fm);
+
+  Iterable<Match> am = new RegExp(r"^\w+$").allMatches(str);
+  Expect.isFalse(am.iterator.moveNext());
+
+  Expect.equals(null, new RegExp(r"^\w+$").stringMatch(str));
+}