public void GetUserById_Test()
{
var userId = 1;
var expected = "AAA";
var user = new User {
UserName = expected, Id = userId
};
var userRepositoryMock = new Mock <IRepository <User> >();
userRepositoryMock.Setup(m => m.GetById(userId)).Returns(user).Verifiable();
var unitOfWorkMock = new Mock <IUnitOfWork>();
unitOfWorkMock.Setup(m => m.UserRepository).Returns(userRepositoryMock.Object);
IUserSystem sut = new UserSystem(unitOfWorkMock.Object);
//Act
var actual = sut.GetUser(userId);
//Assert
userRepositoryMock.Verify();
Assert.IsNotNull(actual);
Assert.AreEqual(expected, actual.UserName);
}