c# - 如何对线程安全队列进行单元测试

Question

我需要一个满足这些要求的简单数据结构:

• 它应该表现得像一个队列，
• 所有入队操作都应该是原子的。

我在多线程方面的经验非常有限，但这是我想到的:

public class Tickets
{
    private ConcurrentQueue<uint> _tickets;

    public Tickets(uint from, uint to)
    {
        Initialize(from, to);
    }

    private readonly object _lock = new object();
    public void Initialize(uint from, uint to)
    {
        lock(_lock)
        {
            _tickets = new ConcurrentQueue<uint>();

            for (uint i = from; i <= to; i++)
            {
                _tickets.Enqueue(i);
            }
        }
    }

    public uint Dequeue()
    {
        uint number;
        if (_tickets.TryDequeue(out number))
        {
            return number;
        }

        throw new ArgumentException("Ticket queue empty!");
    }
}

第一个问题:这段代码可以吗？

第二个问题:我如何对这个类进行单元测试(例如，有两个线程在具有元素(1、2、3、4、5、6)的队列上定期执行出队操作，第一个线程应该只获取奇数和第二个线程只有偶数)？我试过了，但断言没有执行:

[Test]
public void Test()
{
    var tickets = new Tickets(1, 4);
    var t1 = new Thread(() =>
                            {
                                Assert.AreEqual(1, tickets.Dequeue());
                                Thread.Sleep(100);
                                Assert.AreEqual(3, tickets.Dequeue());
                            });


    var t2 = new Thread(() =>
                            {
                                Assert.AreEqual(2, tickets.Dequeue());
                                Thread.Sleep(100);
                                Assert.AreEqual(4, tickets.Dequeue());
                            });

    t1.Start();
    t2.Start();
}

Answer 1

我会用国际象棋:http://research.microsoft.com/en-us/projects/chess

CHESS is a tool for finding and reproducing Heisenbugs in concurrent programs. CHESS repeatedly runs a concurrent test ensuring that every run takes a different interleaving. If an interleaving results in an error, CHESS can reproduce the interleaving for improved debugging. CHESS is available for both managed and native programs.