tests/dartdevc/hot_restart_timer_test.dart

// Copyright (c) 2019, 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:async_helper/async_helper.dart';
import 'package:expect/expect.dart';
import 'dart:async';
import 'dart:_runtime' as dart;

void main() {
  asyncTest(() async {
    await timeoutTest();
    await periodicTest();
  });
}

Future<void> timeoutTest() async {
  bool beforeRestart = true;
  bool calledBeforeRestart = false;
  bool calledAfterRestart = false;
  void callback() {
    if (beforeRestart) {
      calledBeforeRestart = true;
    } else {
      calledAfterRestart = true;
    }
  }

  Timer(Duration(milliseconds: 500), callback);
  dart.hotRestart();
  // The async_helper library will have been reset so retrigger asyncStart.
  asyncStart();
  beforeRestart = false;
  await new Future.delayed(Duration(milliseconds: 600));
  Expect.isFalse(calledBeforeRestart);
  Expect.isFalse(calledAfterRestart);
}

Future<void> periodicTest() async {
  bool beforeRestart = true;
  bool calledBeforeRestart = false;
  bool calledAfterRestart = false;
  void callback(_) {
    if (beforeRestart) {
      calledBeforeRestart = true;
    } else {
      calledAfterRestart = true;
    }
  }

  Timer.periodic(Duration(milliseconds: 10), callback);
  await new Future.delayed(Duration(milliseconds: 100));
  dart.hotRestart();
  // The async_helper library will have been reset so retrigger asyncStart.
  asyncStart();
  beforeRestart = false;
  await new Future.delayed(Duration(milliseconds: 100));
  Expect.isTrue(calledBeforeRestart);
  Expect.isFalse(calledAfterRestart);
}