public void SynchronisedDoubleEndedQueueClearRemovesAllItems()
        {
            var items = new[] { 1, 2, 3, 4, 5, 6, 7, 8 };

            var deque = new SynchronisedDeque <int>(items);

            deque.Clear();

            Assert.AreEqual(0, deque.Count);
        }