c# - Xunit 和 Mock 数据与最小起订量

Question

我是单元测试的新手，任何人都可以建议如何使用 xUnit 和 Moq 测试下面的公共(public)方法 (CreateUser)，谢谢!

public async Task<bool> CreateUser(UserDTO newUser)
{
  newUser.CustomerId = _userResolverService.GetCustomerId();
  if (await CheckUserExists(newUser)) return false;
  var salt = GenerateSalt(10);
  var passwordHash = GenerateHash(newUser.Password, salt);

  await _usersRepository.AddAsync(new User()
  {
    Role = newUser.Role,
    CretedOn = DateTime.Now,
    CustomerId = newUser.CustomerId,
    Email = newUser.Email,
    FirstName = newUser.FirstName,
    LastName = newUser.LastName,
    PasswordHash = passwordHash,
    Salt = salt,
    UpdatedOn = DateTime.Now
  });

  return true;
}

下面的私有(private)方法检查用户是否存在只返回现有用户数

private async Task<bool> CheckUserExists(UserDTO user)
    {
      var users = await _usersRepository.GetAllAsync();
      var userCount = users.Count(u => u.Email == user.Email);
      return userCount > 0;
    }

哈希生成

private static string GenerateHash(string input, string salt)
{
  var bytes = System.Text.Encoding.UTF8.GetBytes(input + salt);
  var sha256 = SHA256.Create();
  var hash = sha256.ComputeHash(bytes);

  return ByteArrayToString(hash);
}

盐世代

private static string GenerateSalt(int size)
{
  var rng = RandomNumberGenerator.Create();
  var buff = new byte[size];
  rng.GetBytes(buff);
  return Convert.ToBase64String(buff);
}



private static string ByteArrayToString(byte[] ba)
{
  var hex = new StringBuilder(ba.Length * 2);
  foreach (byte b in ba)
    hex.AppendFormat("{0:x2}", b);
  return hex.ToString();
}

谢谢，J

编辑 1

这是我目前所拥有的:

    [Fact]
        public async void CreateUser_True()
        {
          //arrange
          var dataSource = new Mock<IRepository<User, int>>();
          var userResolverService = new Mock<IUserResolverService>();
          var tokenService = new Mock<ITokenService>();

      var users = new List<User>();
      users.Add(new User()
      {
        Email = "test@test.com",
        CustomerId = 1
      });
      dataSource.Setup(m => m.GetAllAsync()).ReturnsAsync(users); // Error Here with converting async task to IEnumerable...

          var accountService = new AccountService(dataSource.Object,userResolverService.Object,tokenService.Object);


          //act


          //assert


        }

主要问题是我不知道如何模拟、设置私有(private)方法“CheckUserExists”的行为，因为它正在调用针对类模拟的 IRepository，所以在这种情况下会从这个私有(private)方法返回我的 GetAllAsync 模拟设置方法？

编辑 2

public async Task<TEntity> AddAsync(TEntity entity)
{
  if (entity == null)
  {
    throw new ArgumentNullException(nameof(entity));
  }
  _entities.Add(entity);
  await _context.SaveChangesAsync();
  return entity;
}

编辑 3

[Fact]
public async void CreateUser_True()
{
  //arrange
  var users = new List<User>();
  users.Add(new User()
  {
    Email = "test@test.com",
    CustomerId = 1
  });
  _dataSource.Setup(m => m.GetAllAsync()).ReturnsAsync(users);
  _dataSource.Setup(m => m.AddAsync(It.IsAny<User>())).Returns<User>(Task.FromResult);
  var accountService = new AccountService(_dataSource.Object, _userResolverService.Object, _tokenService.Object);


  //act
  var result = await accountService.CreateUser(new UserDTO()
  {
    Email = "truetest@test.com"
  });

  var updatedUsersList = await _dataSource.Object.GetAllAsync();
  var usersCount = updatedUsersList.Count();

  //assert
  Assert.True(result);
  Assert.Equal(2, usersCount);

}

Answer 1

由于被测试的方法是异步的，您需要设置所有异步依赖项以允许方法流完成。至于私有(private)方法，您想要设置该方法中使用的任何依赖项的行为，在本例中为用户存储库。

[Fact]
public async Task CreateUser_True() {
    //arrange
    var usersRepository = new Mock<IRepository<User, int>>();
    var userResolverService = new Mock<IUserResolverService>();
    var tokenService = new Mock<ITokenService>();

    var user = new User() {
        Email = "test@test.com",
        CustomerId = 1
    };
    var users = new List<User>() { user };

    usersRepository.Setup(_ => _.GetAllAsync()).ReturnsAsync(users);
    usersRepository.Setup(_ => _.AddAsync(It.IsAny<User>()))
        .Returns<User>(arg => Task.FromResult(arg)) //<-- returning the input value from task.
        .Callback<User>(arg => users.Add(arg)); //<-- use call back to perform function
    userResolverService.Setup(_ => _.GetCustomerId()).Returns(2);
    var accountService = new AccountService(usersRepository.Object, userResolverService.Object, tokenService.Object);

    //act
    var actual = await accountService.CreateUser(new UserDto { 
        Email = "email@example.com",
        Password = "monkey123",
        //...other code removed for brevity
    });

    //assert
    Assert.IsTrue(actual);
    Assert.IsTrue(users.Count == 2);
    Assert.IsTrue(users.Any(u => u.CustomerId == 2);
}

继续阅读 Moq Quickstart更好地了解如何使用模拟框架。