任务最小起订量等待

Question

由于我已将我的 WCF 方法转换为 Async，我的单元测试失败了，我无法找出正确的语法来让它们工作。

客户端代理 class

 public interface IClientProxy
{
     Task DoSomething(CredentialDataList credentialData, string store);
}

服务class

  public class CredentialSync : ICredentialSync
{
    private ICredentialRepository _repository;

    private IClientProxy _client;

    public CredentialSync()
    {
        this._repository = new CredentialRepository();
        this._client = new ClientProxy();
    }

    public CredentialSync(ICredentialRepository repository, IClientProxy client)
    {
        this._repository = repository;
        this._client = client;
    }

   public async Task Synchronise(string payrollNumber)
    {
        try
        {
            if (string.IsNullOrEmpty(payrollNumber))
            {
                .... some code
              }
            else
            {
                CredentialDataList credentialData = new CredentialDataList();
                List<CredentialData> credentialList = new List<CredentialData>();

                // fetch the record from the database
                List<GetCredentialData_Result> data = this._repository.GetCredentialData(payrollNumber);
                var pinData = this._repository.GetCredentialPinData(payrollNumber);

                // get the stores for this employee
                var storeList = data.Where(a => a.StoreNumber != null)
                    .GroupBy(a => a.StoreNumber)
                    .Select(x => new Store { StoreNumber = x.Key.ToString() }).ToArray();

                var credential = this.ExtractCredentialData(data, pinData, payrollNumber);

                credentialList.Add(credential);
                credentialData.CredentialList = credentialList;

                foreach (var store in storeList)
                {       
                  //this line causes an Object reference not set to an instance of an object error
                   await  _client.DoSomething(credentialData, store.StoreNumber);

                }
            }
        }
        catch (Exception ex)
        {
            throw new FaultException<Exception>(ex);
        }
    }

测试Class

 /// </summary>
[TestClass]
public class SynchTest
{

    private Mock<ICredentialRepository> _mockRepository;
    private Mock<IClientProxy> _mockService;

    [TestInitialize]
    public void Setup()
    {
       ... some setups for repository which work fine
    }

[TestMethod]      
    public async Task SynchroniseData_WithOneEmployee_CallsReplicateService()
    {
        this._mockService = new Mock<IClientProxy>();
        this._mockService.Setup(x=>x.DoSomething(It.IsAny<CredentialDataList>(), It.IsAny<string>()));
        // arrange
        string payrollNumber = "1";
        CredentialSync service = new CredentialSync(this._mockRepository.Object, this._mockService.Object);

        // act
        await service.Synchronise(payrollNumber);

        // assert                 
        this._mockService.VerifyAll();
    }

调用ClientProxy.DoSomething时出错：

Object reference not set to an instance of an object

参数都没问题

如果我将 ClientProxy.DoSomething 方法转换为同步方法 (public void DoSomething(...) )代码工作正常，但我确实需要异步调用它

Answer 1

DoSomething returns null 而不是 returning a Task，因此在等待时会出现异常。您需要在构建模拟时指定它应该 return a Task.

在这种情况下，您似乎可以使用 Task.FromResult 简单地 return 一个已经完成的任务，因此模拟设置应该如下所示：

this._mockService.Setup(...).Returns(Task.FromResult(false));

从下一版本的 .Net (4.6) 开始，您可以像这样使用 Task.CompletedTask：

this._mockService.Setup(...).Returns(Task.CompletedTask);

Answer 2

我认为你需要 return 来自 DoSomething mock

的 Task

this._mockService.Setup(x => x.DoSomething(It.IsAny<CredentialDataList>(), It.IsAny<string>()))
    .Returns(Task.FromResult<int>(0));

Answer 3

您可以使用 ReturnsAsync

减少代码中的混乱程度

this._mockService.Setup(...).ReturnsAsync(false);

这样你就可以去掉Task.FromResult部分代码

任务最小起订量等待

Moq with Task await

.net

c#

asynchronous

moq

async-await