LibTest/collection/DoubleLinkedQueue/any_A01_t02.dart

// 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 bool any(bool f(E element))
///  Checks whether any element of this iterable satisfies [test].
///  Checks every element in iteration order, and returns [true] if any of them
///  make test return [true], otherwise returns [false].
/// @description Checks that the method returns true if at least one element
/// of this collection satisfies the predicate test.
/// @author kaigorodov

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

main() {
  DoubleLinkedQueue queue = new DoubleLinkedQueue();
  Expect.isFalse(queue.any((e) => false));
  Expect.isFalse(queue.any((e) => true));
  Expect.isFalse(queue.any((e) => e == 1));
  
  queue.addFirst(1);
  Expect.isFalse(queue.any((e) => false));
  Expect.isFalse(queue.any((e) => e == 0));
  Expect.isTrue(queue.any((e) => e == 1));
  
  queue.addFirst(1);
  Expect.isTrue(queue.any((e) => e == 1));
  
  queue.addLast(2);
  Expect.isFalse(queue.any((e) => e == 0));
  Expect.isTrue(queue.any((e) => e == 1));
  Expect.isTrue(queue.any((e) => e == 2));
}