LibTest/collection/Queue/retainWhere_A02_t01.test.dart

// Copyright (c) 2016, 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.

/// @assertion void retainWhere(bool test(E element))
/// ...
/// The [test] function must not throw or modify the queue.
/// @description Checks that if [test] function throws an exception then
/// operation stops
/// @author sgrekhov@unipro.ru

library retainWhere_A02_t01;
 
import "../../../Utils/expect.dart";
import "dart:collection";

bool throwFunction(var element) {
  if (element < 0) {
    return true;
  } else {
    throw new Exception();
  }
}

test(Queue create([Iterable content])) {
  Queue a = create([-3, -2, -1, 0, 1, 2, 3, -1]);
  Expect.throws(() { a.retainWhere(throwFunction); });
  Expect.iterableEquals([-3, -2, -1, 0, 1, 2, 3, -1], a);
}