我正在使用异步xUnit测试,我注意到不一致的传递行为:
public async Task FetchData()
{
//Arrange
var result = await arrangedService.FetchDataAsync().ConfigureAwait(false);
//Assert
}
我已经完成了此测试执行的调用堆栈,并且已经验证我的所有库代码在每个任务之后都在调用 .ConfigureAwait(false)
. 但是,尽管如此,此测试和其他测试在执行 Run All
时会间歇性地失败,但是当我在调试器上完成时,会通过断言和手动检查 . 很明显,我没有正确地做某事 . 我已经尝试在测试中删除对 ConfigureAwait(false)
的调用,以防有特殊的xUnit同步上下文,但它没有改变任何东西 . 以一致的方式测试异步代码的最佳方法是什么?
EDIT 好的,这是我尝试创建一个运行的代码的超简化示例,以提供正在发生的事情的示例:
using Graph = Microsoft.Azure.ActiveDirectory.GraphClient;
public async Task FetchData()
{
var adUsers = baseUsers //IEnumerable<Graph.User>
.Cast<Graph.IUser>()
.ToList();
var nextPageUsers = Enumerable
.Range(GoodIdMin, GoodIdMax)
.Select(number => new Graph.User
{
Mail = (-number).ToString()
})
.Cast<Graph.IUser>()
.ToList();
var mockUserPages = new Mock<IPagedCollection<Graph.IUser>>();
mockUserPages
.Setup(pages => pages.MorePagesAvailable)
.Returns(true);
mockUserPages
.Setup(pages => pages.CurrentPage)
.Returns(new ReadOnlyCollection<Graph.IUser>(adUsers));
mockUserPages
.Setup(pages => pages.GetNextPageAsync())
.ReturnsAsync(mockUserPages.Object)
.Callback(() =>
{
mockUserPages
.Setup(pages => pages.CurrentPage)
.Returns(new ReadOnlyCollection<Graph.IUser>(nextPageUsers));
mockUserPages
.Setup(pages => pages.MorePagesAvailable)
.Returns(false);
});
var mockUsers = new Mock<Graph.IUserCollection>();
mockUsers
.Setup(src => src.ExecuteAsync())
.ReturnsAsync(mockUserPages.Object);
var mockGraphClient = new Mock<Graph.IActiveDirectoryClient>();
mockGraphClient
.Setup(src => src.Users)
.Returns(mockUsers.Object);
var mockDbUsers = CreateBasicMockDbSet(baseUsers.Take(10)
.Select(user => new User
{
Mail = user.Mail
})
.AsQueryable());
var mockContext = new Mock<MyDbContext>();
mockContext
.Setup(context => context.Set<User>())
.Returns(mockDbUsers.Object);
var mockGraphProvider = new Mock<IGraphProvider>();
mockGraphProvider
.Setup(src => src.GetClient()) //Creates an IActiveDirectoryClient
.Returns(mockGraphClient.Object);
var getter = new UserGetter(mockContext.Object, mockGraphProvider.Object);
var result = await getter.GetData().ConfigureAwait(false);
Assert.True(result.Success); //Not the actual assert
}
这是在 var result = ...
行上执行的代码:
public UserGetterResult GetData()
{
var adUsers = await GetAdUsers().ConfigureAwait(false);
var dbUsers = Context.Set<User>().ToList(); //This is the injected context from before
return new UserGetterResult //Just a POCO
{
AdUsers = adUsers
.Except(/*Expression that indicates whether
or not this user is in the database*/)
.ProjectTo<User>()
.ToList(),
DbUsers = dbUsers.ProjectTo<User>().ToList() //Automapper 6.1.1
};
}
private async Task<List<User>> GetAdUsers()
{
var userPages = await client //Injected IActiveDirectoryClient from before
.Users
.ExecuteAsync()
.ConfigureAwait(false);
var users = userPages.CurrentPage.ToList();
while(userPages.MorePagesAvailable)
{
userPages = await userPages.GetNextPageAsync().ConfigureAwait(false);
users.AddRange(userPages.CurrentPage);
}
return users;
}
代码的目的是获取AD中但不是数据库的用户列表以及数据库中的用户列表 .
EDIT EDIT 由于我忘了在原始更新中包含它,因此在调用`IUserCollection.ExecuteAsync()时都会发生错误 .
2 回答
我怀疑问题可能是执行回调和下一次请求mockUserPages.CurrentPage之间的延迟
尝试分离用户页面集合:
IUserCollection.ExecuteAsync()
似乎根据原始帖子中显示的内容正确配置 .现在关注以下方法......
我关心如何在模拟中设置用户页面 . 鉴于
GetAdUsers
方法的流程,最好使用SetupSequence
模拟重复调用CurrentPage
和MorePagesAvailable
.参考Moq Quickstart