Add microsecond support to DateTime.

tests/corelib/date_time4_test.dart

 // 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.
 
 import "package:expect/expect.dart";
 
 // Test fromString with 6 digits after the decimal point.
 
+bool get supportsMicroseconds =>
+    new DateTime.fromMicrosecondsSinceEpoch(1).microsecondsSinceEpoch == 1;
+
+
 main() {
+  if (supportsMicroseconds) {
+    testMicrosecondPrecision();
+  } else {
+    testMillisecondPrecision();
+  }
+}
+
+void testMillisecondPrecision() {
   // We only support milliseconds. If the user supplies more data (the "51"
   // here), we round.
-  // If (eventually) we support more than just milliseconds this test could
-  // fail. Please update the test in this case.
   DateTime dt1 = DateTime.parse("1999-01-02 23:59:59.999519");
   Expect.equals(1999, dt1.year);
   Expect.equals(1, dt1.month);
   Expect.equals(3, dt1.day);
   Expect.equals(0, dt1.hour);
   Expect.equals(0, dt1.minute);
   Expect.equals(0, dt1.second);
   Expect.equals(0, dt1.millisecond);
   Expect.equals(false, dt1.isUtc);
   dt1 = DateTime.parse("1999-01-02 23:58:59.999519Z");
@@ skipping 17 matching lines @@
   String svnDate = "2012-03-30T04:28:13.752341Z";
   dt1 = DateTime.parse(svnDate);
   Expect.equals(2012, dt1.year);
   Expect.equals(3, dt1.month);
   Expect.equals(30, dt1.day);
   Expect.equals(4, dt1.hour);
   Expect.equals(28, dt1.minute);
   Expect.equals(13, dt1.second);
   Expect.equals(752, dt1.millisecond);
   Expect.equals(true, dt1.isUtc);
-  
 }
+
+void testMicrosecondPrecision() {
+  DateTime dt1 = DateTime.parse("1999-01-02 23:59:59.999519");
+  Expect.equals(1999, dt1.year);
+  Expect.equals(1, dt1.month);
+  Expect.equals(2, dt1.day);
+  Expect.equals(23, dt1.hour);
+  Expect.equals(59, dt1.minute);
+  Expect.equals(59, dt1.second);
+  Expect.equals(999, dt1.millisecond);
+  Expect.equals(519, dt1.microsecond);
+  Expect.equals(false, dt1.isUtc);
+  dt1 = DateTime.parse("1999-01-02 23:58:59.999519Z");
+  Expect.equals(1999, dt1.year);
+  Expect.equals(1, dt1.month);
+  Expect.equals(2, dt1.day);
+  Expect.equals(23, dt1.hour);
+  Expect.equals(58, dt1.minute);
+  Expect.equals(59, dt1.second);
+  Expect.equals(999, dt1.millisecond);
+  Expect.equals(519, dt1.microsecond);
+  Expect.equals(true, dt1.isUtc);
+  dt1 = DateTime.parse("0009-09-09 09:09:09.009411Z");
+  Expect.equals(9, dt1.year);
+  Expect.equals(9, dt1.month);
+  Expect.equals(9, dt1.day);
+  Expect.equals(9, dt1.hour);
+  Expect.equals(9, dt1.minute);
+  Expect.equals(9, dt1.second);
+  Expect.equals(9, dt1.millisecond);
+  Expect.equals(411, dt1.microsecond);
+  Expect.equals(true, dt1.isUtc);
+  String svnDate = "2012-03-30T04:28:13.752341Z";
+  dt1 = DateTime.parse(svnDate);
+  Expect.equals(2012, dt1.year);
+  Expect.equals(3, dt1.month);
+  Expect.equals(30, dt1.day);
+  Expect.equals(4, dt1.hour);
+  Expect.equals(28, dt1.minute);
+  Expect.equals(13, dt1.second);
+  Expect.equals(752, dt1.millisecond);
+  Expect.equals(341, dt1.microsecond);
+  Expect.equals(true, dt1.isUtc);
+}