| // 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 = 2.9 |
| |
| library timer_test; |
| |
| import 'dart:async'; |
| import 'package:expect/expect.dart'; |
| import 'package:async_helper/async_helper.dart'; |
| |
| const ms = const Duration(milliseconds: 1); |
| |
| expectGTE(min, actual, msg) { |
| if (actual >= min) return; |
| Expect.fail(msg.replaceAll('{0}', "$min").replaceAll('{1}', "$actual")); |
| } |
| |
| main() { |
| int interval = 20; |
| asyncStart(); |
| var sw = new Stopwatch()..start(); |
| int nextTick = 1; |
| bool running = true; |
| var timer = new Timer.periodic(ms * interval, (t) { |
| expectGTE(nextTick, t.tick, "tick {1} before expect next tick {0}."); |
| nextTick += 1; |
| int time = sw.elapsedMilliseconds; |
| int minTime = interval * t.tick; |
| expectGTE(minTime, time, "Actual time {1} before {0} at tick ${t.tick}"); |
| if (t.tick > 20) { |
| running = false; |
| t.cancel(); |
| asyncEnd(); |
| } |
| }); |
| |
| /// Test that ticks still happen when the rest of the system is slow. |
| delay() { |
| int time = new DateTime.now().millisecondsSinceEpoch; |
| int limit = time + 3 * interval; |
| while (new DateTime.now().millisecondsSinceEpoch < limit) { |
| // Idle. |
| } |
| nextTick = timer.tick + 2; // At least increment by two, probably more. |
| if (running) Timer.run(delay); |
| } |
| |
| Timer.run(delay); |
| } |