我如何模拟 AddAsync？

Question

我正在编写单元测试。为了测试下面的方法，

public async Task<Guid> CreateWebJobStatus(string blobId, Guid loggedInUserId, string loggedInUserEmail) {

    Guid webJobStatusId = Guid.NewGuid();

    WebJobStatus newWebJobStatus = new WebJobStatus
    {
        WorkJobStatusId = webJobStatusId,
        TransactionId = Guid.NewGuid(),
        Status = (int)WebJobStatusEnum.PENDING,
        BlobId = blobId,
        UserId = loggedInUserId,
        UserEmail = loggedInUserEmail,
    };
    await _dbContext.WebJobStatus.AddAsync(newWebJobStatus);
    await _dbContext.SaveChangesAsync();

    return webJobStatusId;
}

我模拟了 dbset 和 dbcontext

public async void CreateWebJobStatusTest() {
    var dbOption = new DbContextOptions<TimeSeriesDbContext>();
    var mockDbContext = new Mock<TimeSeriesDbContext>(dbOption);
    var mockConfig = new Mock<IConfiguration>();
    var instance = new WebJobStatusRepository(mockConfig.Object, mockDbContext.Object);
    var mockValidWebJobId = "11111111-1111-1111-1111-111111111111";
    var webjobStatusList = new List<WebJobStatus>() {
        new WebJobStatus {
            WorkJobStatusId = Guid.Parse(mockValidWebJobId),
            GroupName = "testGroupName",
            Status = 3,
            CreatedDate = DateTimeOffset.UtcNow.AddDays(-10)
        }
    };
    var mockWebJobDbSet = UnitTestUtil.CreateDbSetMock<WebJobStatus>(webjobStatusList.AsQueryable());
    mockDbContext.Setup(x => x.WebJobStatus).Returns(mockWebJobDbSet.Object);

    mockWebJobDbSet.Setup(x => x.AddAsync(It.IsAny<WebJobStatus>(), It.IsAny<System.Threading.CancellationToken>())).Callback((WebJobStatus wj) =>{webjobstatusList.add(wj);});


    var mockuserId = Guid.Parse("22222222-1111-1111-1111-111111111111");

    var result = await instance.CreateWebJobStatus("testBlobId.tsv", mockuserId, "testEmail");
    Assert.IsType<Guid>(result);
    mockDbContext.Verify(x => x.SaveChangesAsync(It.IsAny<System.Threading.CancellationToken>()), Times.Once);
    mockWebJobDbSet.Verify(x => x.AddAsync(It.IsAny<WebJobStatus>(), It.IsAny<System.Threading.CancellationToken>()), Times.Once);
}

除 AddAsync 外，一切正常，例外是

Invalid callback. Setup on method with parameters (WebJobStatus,CancellationToken) cannot invoke callback with parameters (WebJobStatus).

有人知道吗？

Answer 1

您将需要 return 一个任务以允许 async/await 调用

await _dbContext.WebJobStatus.AddAsync(newWebJobStatus);

流向完成。

所以假设 Add returns 添加了对象

mockWebJobDbSet
    .Setup(_ => _.AddAsync(It.IsAny<WebJobStatus>(), It.IsAny<System.Threading.CancellationToken>()))
    .Callback((WebJobStatus model, CancellationToken token) => { webjobstatusList.Add(model); })
    .Returns((WebJobStatus model, CancellationToken token) => Task.FromResult((EntityEntry<WebJobStatus>)null));

请注意，Setup 方法有两个参数，因此 Callback 和 Returns 如果要使用捕获的参数，也需要有两个参数。

Answer 2

在 .net core 3.1 中，我不得不重写 Returns 如下：

.Returns((T model, CancellationToken token) => new ValueTask<EntityEntry<T>>());

Answer 3

不漂亮，但这是我发现模拟 AddAsync 并使其 return 成为实际值的唯一方法：

mockWebJobDbSet
.Setup(_ => _.AddAsync(It.IsAny<WebJobStatus>(), It.IsAny<CancellationToken>()))
.Callback((WebJobStatus model, CancellationToken token) => { webjobStatusList.Add(model); })
.Returns((WebJobStatus model, CancellationToken token) => ValueTask.FromResult(new EntityEntry<WebJobStatus>
(new InternalEntityEntry(
    new Mock<IStateManager>().Object,
    new RuntimeEntityType("WebJobStatus", typeof(WebJobStatus), false, null, null, null, ChangeTrackingStrategy.Snapshot, null, false),
    model)
)));

Answer 4

我模拟的方式如下：-

var myList = new List<MyClass>();
       
_dataContext.Setup(m => m.MyClasses.AddAsync(It.IsAny<MyClass>(), default))
            .Callback<Slide, CancellationToken>((s, token) => {myList.Add(s);});
        
_dataContext.Setup(c => c.SaveChangesAsync(default))
            .Returns(Task.FromResult(1))
            .Verifiable();

实际执行情况如下：-

public async Task<int> AddMyClassAsync(MyClass myClass)
{
    await _careMapsDataContext.MyClasses.AddAsync(myClass);
        
    return await _careMapsDataContext.SaveChangesAsync();
}

我如何模拟 AddAsync？

How do I mock AddAsync?

c#

unit-testing

moq

xunit

entity-framework-core