// 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

/// @assertion void clear()
/// Removes all elements in the queue. The size of the queue becomes zero.
/// @description Checks that all elements of the queue removed.
/// @author kaigorodov

import "../../../Utils/expect.dart";
import "dart:collection";

main() {
  DoubleLinkedQueue list = new DoubleLinkedQueue();
  list.clear();
  Expect.isTrue(list.isEmpty);
  
  list.addFirst(1);
  list.addFirst(1);
  Expect.isFalse(list.isEmpty);
  list.clear();
  Expect.isTrue(list.isEmpty);
  list.clear();
  Expect.isTrue(list.isEmpty);
  for(int i = 0; i < 1000; i++) {
    list.add(i);
  }
  list.clear();
  Expect.isTrue(list.isEmpty);
}