Very simple version of Isolates.

runtime/tests/vm/dart/isolate_unhandled_exception_uri_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.
-
-library isolate_unhandled_exception_uri_helper;
-
-import "package:expect/expect.dart";
-import 'dart:async';
-import 'dart:isolate';
-
-// Tests that isolate code in another script keeps message handling working
-// after throwing an unhandled exception, if it has a function called
-// unhandledExceptionCallback that returns true (continue handling).
-
-// Note: this test will hang if an uncaught exception isn't handled,
-// either by an error in the callback or it returning false.
-
-void main() {
-  var isolate_port = spawnUri('isolate_unhandled_exception_uri_helper.dart');
-
-  // Send a message that will cause an ignorable exception to be thrown.
-  Future f = isolate_port.call('throw exception');
-  f.catchError((error) {
-    Expect.fail("Error not expected");
-  });
-
-  // Verify that isolate can still handle messages.
-  isolate_port.call('hi').then((value) {
-    Expect.equals('hello', value);
-  }, onError: (error) {
-    Expect.fail("Error not expected");
-  });
-
-}