如何使用 Moq 和 xUnit 测试异步方法

Question

I am having the following method which calls an insert and update methods.

Conditions

1. In the below ProcessBspLoan function, I am calling other function named getBspData if getBspData returns any result. I will insert the result and update the database as a success for a particular Id

2. if getBspData throws any Exception I will only update the database as a fail for a particular Id without inserting

Here is the ProcessBspLoan function in the given class

    public class BspLoanProcessor : IBspLoanProcessor
    {
        private readonly IBspClient _bspService;
        private readonly IBspRepository _bspRepository;
        private readonly ILogger<BspLoanProcessor> _logger;
        private readonly IMapper _mapper;
        private readonly IFhaRepository _fhaRepository;

        public BspLoanProcessor(IBspClient bspService, ILogger<BspLoanProcessor> logger, 
            IMapper mapper, IBspRepository bSPRepository, IFhaRepository fhaRepository)
        {
            _bspService = bspService;
            _logger = logger;
            _mapper = mapper;
            _bspRepository = bSPRepository;
            _fhaRepository = fhaRepository;
        }

        public async Task<bool> ProcessBspLoan(BspLoanDetails bspLoanDetails, string transactionId, string triggerType)
        {
            FhaTransactionDetails fhaData = _mapper.Map<FhaTransactionDetails>(bspLoanDetails);

            try
            {
                ////////////////////////////Calling getBspData///////////////////////////////////////
                var result = await _bspService.getBspData(bspLoanDetails.NsmLoanNumber, transactionId);

                result.TransactionId = transactionId;

                await _bspRepository.InsertBspResponse(result);
                
                await _fhaRepository.UpdateFhaTransactionWithLoanNumber(transactionId,"SUCCESS");
                return true;
            }
            catch(Exception ex)
            {
                await _fhaRepository.UpdateFhaTransactionWithLoanNumber(transactionId,"FAIL");
                return false;
            }
        }
    }

I wrote the test method for the above function want to check it is returning true or false based on inputs provided

Here is my test function

    public async Task Test1Async()
    {
        Mock<IBspLoanProcessor> _bspLoanProcessor = new Mock<IBspLoanProcessor>();
        Mock<IBspRepository> _bspRepository = new Mock<IBspRepository>();
        Mock<IFhaRepository> _fhaRepository = new Mock<IFhaRepository>();
        Mock<IBspClient> _bspClient = new Mock<IBspClient>();
        BspLoanDetails bspLoanDetails = new BspLoanDetails
        {
            TriggerType = "BLOB",
            Attempts = 1,
            FirstRunDateTime = DateTime.Now.ToUniversalTime()
        };
        ----> 1
        _bspClient.Setup(x => x.getBspData(It.IsAny<string>(), It.IsAny<string>())).Returns(Task.FromResult(new BspResponseDetails()));
        ----> 2
        _bspRepository.Setup(x => x.InsertBspResponse(It.IsAny<BspResponseDetails>())).Returns(Task.CompletedTask);
        ----> 3
        _fhaRepository.Setup(x => x.UpdateFhaTransactionWithLoanNumber(It.IsAny<string>(),It.IsAny<string>())).Returns(Task.CompletedTask);
        bool value = await _bspLoanProcessor.Object.ProcessBspLoan(bspLoanDetails, "123", "SCHEDULE");
        Assert.True(value);
    }

In the above the test, I am checking the first condition

1. I am returning data as an object whenever anyone called gets data
2. Inserting BspResponsemethod also I am returning task.completedTask
3. UpdateFhaTransactionWithLoanNumber also I am returning task.completedTask

The actual expected output is true, but it is returning false.

I am new to Moq and xUnit. Please help me to resolve this issue and also test async and await methods.

IBspClient interface

    public interface IBspClient
    {
        Task<BspResponseDetails> getBspData(string loanNumber,string tid);

        Task<BspHealthCheck> GetHealthStatus();
    }

IBspRepository Interface

    public interface IBspRepository
    {
        Task InsertBspResponse(BspResponseDetails bsp);
    }

IFhaRepository interface

    public interface IFhaRepository
    {
        Task UpdateFhaTransactionWithLoanNumber(string tid, string status);    
    }

Thanks in advance

Answer 1

bool value = await _bspLoanProcessor.Object

You're calling a method on your mock. You shouldn't mock the system-under-test, you only mock its dependencies.

Just new the class you want to test, otherwise you will be testing that your mock framework does what you set it up to.

And because you didn't setup ProcessBspLoan() , it returns the default for its return value, so false .