Very simple version of Isolates.

tests/isolate/spawn_uri_nested_vm_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.
 
 // Example of nested spawning of isolates from a URI
 // Note: the following comment is used by test.dart to additionally compile the
 // other isolate's code.
 // OtherScripts=spawn_uri_nested_child1_vm_isolate.dart spawn_uri_nested_child2_vm_isolate.dart
 library NestedSpawnUriLibrary;
 import 'dart:isolate';
 import '../../pkg/unittest/lib/unittest.dart';
 
 main() {
   test('isolate fromUri - nested send and reply', () {
-    var port = spawnUri('spawn_uri_nested_child1_vm_isolate.dart');
-
-    port.call([1, 2]).then((result) => print(result));
+    ReceivePort port = new ReceivePort();
+    Isolate.spawnUri(Uri.parse('spawn_uri_nested_child1_vm_isolate.dart'),
+                     [], [[1, 2], port.sendPort]);
+    port.first.then(expectAsync1((result) => print(result)));
   });
 }