tests/lib/isolate/cross_isolate_message_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.

// Dart test program for testing that isolates can communicate to isolates
// other than the main isolate.

library CrossIsolateMessageTest;

import 'dart:isolate';
import 'package:async_helper/async_helper.dart';
import 'package:expect/expect.dart';

/*
 * Everything starts in the main-isolate (in the main-method).
 * The main isolate spawns two isolates: isolate1 (with entry point
 * 'crossIsolate1') and isolate2 (with entry point 'crossIsolate2').
 *
 * The main isolate creates two isolates, isolate1 and isolate2.
 * The second isolate is created with a send-port being listened on by
 * isolate1. A message is passed along this from isolate2 to isolate1.
 * Isolate1 then sends the result back to the main isolate for final checking.
 */

void crossIsolate1(SendPort mainIsolate) {
  ReceivePort local = new ReceivePort();
  mainIsolate.send(["ready1", local.sendPort]);
  local.first.then((msg) {
    // Message from crossIsolate2
    Expect.equals(msg[0], "fromIsolate2");
    mainIsolate.send(["fromIsolate1", msg[1] + 58]); // 100.
  });
}

void crossIsolate2(SendPort toIsolate1) {
  toIsolate1.send(["fromIsolate2", 42]);
}

void main([args, port]) {
  ReceivePort fromIsolate1 = new ReceivePort();
  Isolate.spawn(crossIsolate1, fromIsolate1.sendPort);

  asyncStart();
  fromIsolate1.listen((msg) {
    switch (msg[0]) {
      case "ready1":
        SendPort toIsolate1 = msg[1];
        Isolate.spawn(crossIsolate2, toIsolate1);
        break;
      case "fromIsolate1":
        Expect.equals(msg[1], 100);
        fromIsolate1.close();
        break;
      default:
        Expect.fail("unreachable! Tag: ${msg[0]}");
    }
  }, onDone: asyncEnd);
}