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Mocked method do not pass correct value

I am trying to understand how mocking works in Xunit with AutoFixture. I have created Service and Repository classes and their interfaces. Mocked method should pass value which is different from default value.
Mocked method always pass default values instead of values which i am writing in ".Returns()". I have tried AutoConfiguredMoqCustomization but it provides completely random values which i can't get back.
Repository.cs
public class Repository : IRepository
{
public int GetInt()
{
return 999;
}
}
Service.cs
public class Service : IService
{
private readonly Repository _repository;
public Service()
{
_repository = new Repository();
}
public string GetStringFromInt()
{
return _repository.GetInt().ToString();
}
}
Test
[Fact]
public void Test()
{
var fixture = new Fixture().Customize(new AutoMoqCustomization());
var repositoryMock = fixture.Create<Mock<IRepository>>();
var service = fixture.Create<Service>();
repositoryMock.Setup(x => x.GetInt()).Returns(1);
var act = service.GetStringFromInt();
Assert.Equal("1", act);
}
As you see value by default in Repository is 999 and I am expecting 1 from repositoryMock but result is "999" instead of "1".
Ow I have understood my problem. When I declare parameters with auto moq testing service must be AFTER all mocked repositories
Test
[Theory, AutoMoqData]
public void Test([Frozen] Mock<IRepository> repositoryMock, Service service)
{
...
}
Attribute
public class AutoMoqDataAttribute : AutoDataAttribute
{
public AutoMoqDataAttribute() : base(GetDefaultFixture)
{
}
private static IFixture GetDefaultFixture()
{
return new Fixture().Customize(new AutoMoqCustomization());
}
}

You should freeze your mock first. When you call Create on AutoFixture, it will create you a new instance every time. Try the following in the modified code (where you are using an interface of the type in your constructor).
public class ServiceTests
{
private readonly IFixture fixture = new Fixture().Customize(new AutoMoqCustomization());
public ServiceTests()
{
fixture.Register<IService>(() => fixture.Create<Service>());
}
[Fact]
public void Test()
{
// Arrange
var repositoryMock = fixture.Freeze<Mock<IRepository>>();
repositoryMock.Setup(x => x.GetInt()).Returns(1);
var service = fixture.Create<IService>();
// Act
var act = service.GetStringFromInt();
// Verify
Assert.Equal("1", act);
}
}
To check that you have set up autofixture correctly, you can try the following in the unit test in future.
var repo1 = fixture.Create<IRepository>();
var repo2 = fixture.Create<IRepository>();
Assert.Equal(repo1.GetHashCode(), repo2.GetHashCode());
If the above fails, that indicates that you have not frozen a type. These lines of code have saved me so much head scratching in the past...

You are doing DI wrong, you are not injecting Repository into Your serice.
Try like this.
public class Repository : IRepository
{
public int GetInt()
{
return 999;
}
}
public class Service : IService
{
IRepository Repository;
public Service(IRepository repository)
{
this.Repository = repository;
}
public string GetStringFromInt()
{
return Repository.GetInt().ToString();
}
}
Now when you mock IRepository, you can add it to Service.
You are using a new Repository() in constructor, so you are using that implementation

How to mock UserManager in .Net Core testing?

I have following code. Im trying to running a test case for create user.Following is what i have tried so far.
public class CreateUserCommandHandlerTest
{
private Mock<UserManager<ApplicationUser>> _userManager;
private CreateUserCommandHandler _systemUnderTest;
public CreateUserCommandHandlerTest()
{
_userManager = MockUserManager.GetUserManager<ApplicationUser>();
var user = new ApplicationUser() { UserName = "ancon1", Email = "ancon#mail.com", RoleType = RoleTypes.Anonymous };
_userManager
.Setup(u => u.CreateAsync(user, "ancon2")).ReturnsAsync(IdentityResult.Success);
_systemUnderTest = new CreateUserCommandHandler(_userManager.Object);
}
[Fact]
public async void Handle_GivenValidInput_ReturnsCreatedResponse()
{
var command = new CreateUserCommand { Username = "ancon1", Email = "ancon#mail.com", Password = "ancon2", RoleType = RoleTypes.Anonymous };
var result = await _systemUnderTest.Handle(command, default(CancellationToken));
Assert.NotNull(result);
Assert.IsType<Application.Commands.CreatedResponse>(result);
}
}
My User manager is here:
public static class MockUserManager
{
public static Mock<UserManager<TUser>> GetUserManager<TUser>()
where TUser : class
{
var store = new Mock<IUserStore<TUser>>();
var passwordHasher = new Mock<IPasswordHasher<TUser>>();
IList<IUserValidator<TUser>> userValidators = new List<IUserValidator<TUser>>
{
new UserValidator<TUser>()
};
IList<IPasswordValidator<TUser>> passwordValidators = new List<IPasswordValidator<TUser>>
{
new PasswordValidator<TUser>()
};
userValidators.Add(new UserValidator<TUser>());
passwordValidators.Add(new PasswordValidator<TUser>());
var userManager = new Mock<UserManager<TUser>>(store.Object, null, passwordHasher.Object, userValidators, passwordValidators, null, null, null, null);
return userManager;
}
}
and my Command handler is this:
public class CreateUserCommandHandler : IRequestHandler<CreateUserCommand, BaseCommandResponse>
{
private readonly UserManager<ApplicationUser> _userManager;
public CreateUserCommandHandler(UserManager<ApplicationUser> userManager)
{
_userManager = userManager;
}
public async Task<BaseCommandResponse> Handle(CreateUserCommand createUserCommand, CancellationToken cancellationToken)
{
var user = new ApplicationUser { UserName = createUserCommand.Username, Email = createUserCommand.Email, RoleType = createUserCommand.RoleType };
var result = await _userManager.CreateAsync(user, createUserCommand.Password);
if (result.Succeeded)
{
return new CreatedResponse();
}
ErrorResponse errorResponse = new ErrorResponse(result.Errors.Select(e => e.Description).First());
return errorResponse;
}
}
when i'm running my test it fails and saying Object reference not set to an instant of an object.
What am i doing wrong here??

I know this is months old but I keep getting back to this thread. I will extend my own answer on this topic because just pointing to Haok's GitHub example is like saying: "Read a book" as it is huge. It does not pinpoint the issue and what you need to do. You need to isolate a Mock object, but not only that but also you need to 'Setup' the method for 'CreateAsync'. So let's put this in three parts:
You need to MOCK if you are using MOQ or a similar framework to make a mocked up creation of the UserManager.
You need to Setup the methods of UserManager you expect to get results back from.
Optionally you would want to inject some generic list from a mocked Entity Framework Core 2.1 or similar so that you can actually see that a list of IDentity Users actually increases or decreases. Not just that UserManager succeeded and nothing else
So say I have a helper method for returning a Mocked UserManager. Which is just slightly altered from the Haok code:
public static Mock<UserManager<TUser>> MockUserManager<TUser>(List<TUser> ls) where TUser : class
{
var store = new Mock<IUserStore<TUser>>();
var mgr = new Mock<UserManager<TUser>>(store.Object, null, null, null, null, null, null, null, null);
mgr.Object.UserValidators.Add(new UserValidator<TUser>());
mgr.Object.PasswordValidators.Add(new PasswordValidator<TUser>());
mgr.Setup(x => x.DeleteAsync(It.IsAny<TUser>())).ReturnsAsync(IdentityResult.Success);
mgr.Setup(x => x.CreateAsync(It.IsAny<TUser>(), It.IsAny<string>())).ReturnsAsync(IdentityResult.Success).Callback<TUser, string>((x, y) => ls.Add(x));
mgr.Setup(x => x.UpdateAsync(It.IsAny<TUser>())).ReturnsAsync(IdentityResult.Success);
return mgr;
}
What is key to this is I am injecting a generic 'TUser' that is what I will be testing as well injecting a list of this. Similar to my example of:
private List<ApplicationUser> _users = new List<ApplicationUser>
{
new ApplicationUser("User1", "user1#bv.com") { Id = 1 },
new ApplicationUser("User2", "user2#bv.com") { Id = 2 }
};
...
private _userManager = MockUserManager<ApplicationUser>(_users).Object;
Then finally I am testing a pattern with a repository similar to this implementation I want to test:
public async Task<int> CreateUser(ApplicationUser user, string password) => (await _userManager.CreateAsync(user, password)).Succeeded ? user.Id : -1;
I test it like this:
[Fact]
public async Task CreateAUser()
{
var newUser = new ApplicationUser("NewUser", "New#test.com");
var password = "P#ssw0rd!";
var result = await CreateUser(newUser, password);
Assert.Equal(3, _users.Count);
}
The key to what I did is that not only did I 'Setup' the CreateAsync but I provided a callback so I can actually see my list I inject get incremented. Hope this helps someone.

aspnet/Identity is opensource so what you can do is see how they mock it themselves.
Here's how they do it: MockHelpers.cs
TestUserManager
public static UserManager<TUser> TestUserManager<TUser>(IUserStore<TUser> store = null) where TUser : class
{
store = store ?? new Mock<IUserStore<TUser>>().Object;
var options = new Mock<IOptions<IdentityOptions>>();
var idOptions = new IdentityOptions();
idOptions.Lockout.AllowedForNewUsers = false;
options.Setup(o => o.Value).Returns(idOptions);
var userValidators = new List<IUserValidator<TUser>>();
var validator = new Mock<IUserValidator<TUser>>();
userValidators.Add(validator.Object);
var pwdValidators = new List<PasswordValidator<TUser>>();
pwdValidators.Add(new PasswordValidator<TUser>());
var userManager = new UserManager<TUser>(store, options.Object, new PasswordHasher<TUser>(),
userValidators, pwdValidators, new UpperInvariantLookupNormalizer(),
new IdentityErrorDescriber(), null,
new Mock<ILogger<UserManager<TUser>>>().Object);
validator.Setup(v => v.ValidateAsync(userManager, It.IsAny<TUser>()))
.Returns(Task.FromResult(IdentityResult.Success)).Verifiable();
return userManager;
}

In .NetCore 2.2 you have to do it slightly different. Treat it like an update to #Nick Chapsas answer.
First of all, you have to use IUserPasswordStore instead of IUserStore. IUserPasswordStore inherits IUserStore, but UserManager would like to get IUserPasswordStore. In other way, some things won't work.
If you want to test real behaviour of UserManager (for example CreateUserAsync), you can use real implementations of UserValidator and PasswordValidator. You may want to just to be sure that your method reacts how it supposed to for CreateUser errors.
This is my updated example:
UserManager<TUser> CreateUserManager() where TUser : class
{
Mock<IUserPasswordStore<TUser>> userPasswordStore = new Mock<IUserPasswordStore<TUser>>();
userPasswordStore.Setup(s => s.CreateAsync(It.IsAny<TUser>(), It.IsAny<CancellationToken>()))
.Returns(Task.FromResult(IdentityResult.Success));
var options = new Mock<IOptions<IdentityOptions>>();
var idOptions = new IdentityOptions();
//this should be keep in sync with settings in ConfigureIdentity in WebApi -> Startup.cs
idOptions.Lockout.AllowedForNewUsers = false;
idOptions.Password.RequireDigit = true;
idOptions.Password.RequireLowercase = true;
idOptions.Password.RequireNonAlphanumeric = true;
idOptions.Password.RequireUppercase = true;
idOptions.Password.RequiredLength = 8;
idOptions.Password.RequiredUniqueChars = 1;
idOptions.SignIn.RequireConfirmedEmail = false;
// Lockout settings.
idOptions.Lockout.DefaultLockoutTimeSpan = TimeSpan.FromMinutes(5);
idOptions.Lockout.MaxFailedAccessAttempts = 5;
idOptions.Lockout.AllowedForNewUsers = true;
options.Setup(o => o.Value).Returns(idOptions);
var userValidators = new List<IUserValidator<TUser>>();
UserValidator<TUser> validator = new UserValidator<TUser>();
userValidators.Add(validator);
var passValidator = new PasswordValidator<TUser>();
var pwdValidators = new List<IPasswordValidator<TUser>>();
pwdValidators.Add(passValidator);
var userManager = new UserManager<TUser>(userPasswordStore.Object, options.Object, new PasswordHasher<TUser>(),
userValidators, pwdValidators, new UpperInvariantLookupNormalizer(),
new IdentityErrorDescriber(), null,
new Mock<ILogger<UserManager<TUser>>>().Object);
return userManager;
}
Notice that UserPasswordStore has a method (CreateAsync) that should be mocked if you want to test CreateAsync from UserManager.
Password and Lockout settings are taken from my project. They should be kept in sync with your settings, so that you can test the real thing.
Of course you don't test for example PasswordValidator, but you can test your methods, for example:
//Part of user service
public async Task<IdentityResult> Register(UserDto data)
{
SystemUser user = ConvertDtoToUser(data);
IdentityResult result = userManager.CreateAsync(user, data.Password);
//some more code that is dependent on the result
}

Unable to get Default Constructor

I an getting the below issue when running the Unit Test project.
Unable to get Default Constructor For class ********
[TestClass]
public class PersonRegistration
{
private ILoggingService _loggingService;
private IUserManager _userManager;
public PersonRegistration(IUserManager userManager, ILoggingService loggingService)
{
this._userManager = userManager;
this._loggingService = loggingService;
}
[TestMethod]
public void TestMethod1()
{
RegisterBindingModel model = new RegisterBindingModel();
AccountController ac = new AccountController(_userManager, _loggingService);
model.UserName = "test123#gmail.com";
var result = ac.Register(model);
Assert.AreEqual("User Registered Successfully", result);
}
How to fix that. Some answers says that to use a parameter less constructor. But here I need params.
RegisterBindingModel()
public class RegisterBindingModel
{
public RegisterBindingModel();
[Display(Name = "User name")]
[Required]
public string UserName { get; set; }
}
Issue

I've just tested this in my unit tests.
Add
public PersonRegistration()
{
}
And it should run fine.
There is no need for constructors on your unit test classses. If you are using a mocking framework like Moq then I use a factory to return the dependent moqs for the classes I'm testing.
public ILoggingService ReturnMockLoggingService()
{
var mockService = new Mock<ILoggingService>();
return mockService.Object;
}
Then in the test fixture.
[TestMethod]
public void TestMethod1()
{
RegisterBindingModel model = new RegisterBindingModel();
var logService = MockFactory.ReturnMockLoggingService();
var userService = MockFactory.ReturnMockUserService();
AccountController ac = new AccountController(userService, logService);
model.UserName = "test123#gmail.com";
var result = ac.Register(model);
Assert.AreEqual("User Registered Successfully", result);
}
if you're not using mocks then simply instance the user and log service in the test or create a SetUp.
[ClassInitialize]
public void SetUp()
{
_loggingService = new LoggingService();
_userManager = new UserManager();
}
Hope that helps.

You should use a mocking framework like Moq.
Example:
[TestClass]
public class PersonRegistration
{
[TestMethod]
public void TestMethod()
{
RegisterBindingModel model = new RegisterBindingModel();
var mockService = new Mock<ILoggingService>();//Mock
//Do something as per your requirement
//var reg= new List<RegisterBindingModel >(); // provide some sample list
//mockService .Setup(r => r.GetAll=()).Return(reg);
var mockManager = new Mock<IUserManager>();//Mock
//Do something as per your requirement
//var user= new List<User>(); // provide some sample list
//mockManager .Setup(r => r.GetAll=()).Return(user);
AccountController ac = new AccountController(mockManager.Object, mockService.Object);
model.UserName = "test123#gmail.com";
var result = ac.Register(model);
Assert.AreEqual("User Registered Successfully", result);
}
}
You can get help form this and this link.

How to write a simple testing case using XUnit?

Totally new to testing, I have a controller like this:
public class CheckRegController : Controller
{
private readonly ApplicationDbContext _context;
private readonly AppSettings _appSettings;
public CheckRegController(ApplicationDbContext context, IOptions<AppSettings> appSettings)
{
_context = context;
_appSettings = appSettings.Value;
}
[HttpGet]
public IActionResult Get(string var1, int numberusers)
{
//...
}
}
Now I have added a test project in which I am trying to use XUnit and Moq. I just wanted to create an object of controller like I have done in a very simple project, but it doesn't work in this.When I tried:
CheckRegController cr = new CheckRegController();
It says:
There is no argument given that corresponds to the required formal
parameter 'context' of
'CheckRegController.CheckRegController(ApplicationDbContext,
IOptions)' XUnitTestProjectOA
Then I tried:
var moqHome = new Mock<ApplicationDbContext>();
but I don't know is it right or not OR what I need to do ahead?
How to pass _context and _appsettings ??

You were on the right track. Mock the dependencies and inject them into the subject under test.
//Arrange
var dbmock = new Mock<ApplicationDbContext>();
//...setup dbmock as needed to exercise test
var options = new Mock<IOption<AppSetting>();
var appSetting = new AppSetting {
//...populate appSetting as needed to exercise test
};
options.Setup(_ => _.Value).Returns(appSetting);
var sut = new CheckRegController(dbMock.Object, options.Object);
var var1 = "testing";
var numberusers = 2;
//Act
var actual = sut.Get(var1,numberusers)
//Assert
//...assert expected behavior to actual.
I would also suggest abstracting away the context to also make the controller more maintainable.

Mocking Session not working in MVC 5

I'm storing values in the Session in my controller Action being tested. I've read several articles on how to mock a session and I'm trying to implement Milox's answer to Setting the httpcontext current session in unit test. But when I drill into Locals | this | base | HttpContext Sessions is still null and the test fails with a Null Reference exception when setting the Session variable HttpContext.Session["BsAcId"] = vM.BusAcnt.Id;
This is working production code. vM.BusAcnt.Id returns a valid int and if I substitute it with an int value the test still fails because the Session is null and therefore no value can be stored in it.
I'm using MVC5, EF6, and the latest versions of xUnit, Moq and the Resharper test runner.
Action:
public ActionResult Details(int id)
{
var vM = new BusAcntVm();
vM.BusAcnt = _db.BusAcnts.FirstOrDefault(bA => bA.Id == id);
if ((User.IsInRole("Admin"))) return RedirectToAction("Action");
HttpContext.Session["BsAcId"] = vM.BusAcnt.Id;
return View(vM);
}
MockHelpers:
public static class MockHelpers
{
public static HttpContext FakeHttpContext()
{
var httpRequest = new HttpRequest("", "http://localhost/", "");
var stringWriter = new StringWriter();
var httpResponce = new HttpResponse(stringWriter);
var httpContext = new HttpContext(httpRequest, httpResponce);
var sessionContainer = new HttpSessionStateContainer("id", new SessionStateItemCollection(),
new HttpStaticObjectsCollection(), 10, true,
HttpCookieMode.AutoDetect,
SessionStateMode.InProc, false);
httpContext.Items["AspSession"] = typeof(HttpSessionState).GetConstructor(
BindingFlags.NonPublic | BindingFlags.Instance,
null, CallingConventions.Standard,
new[] { typeof(HttpSessionStateContainer) },
null)
.Invoke(new object[] { sessionContainer });
return httpContext;
}
}
Test:
[Fact]
public void AdminGetBusAcntById()
{
HttpContext.Current = MockHelpers.FakeHttpContext();
var mockMyDb = MockDbSetup.MockMyDb();
var controller = new BusAcntController(mockMy.Object);
var controllerContextMock = new Mock<ControllerContext>();
controllerContextMock.Setup( x => x.HttpContext.User.
IsInRole(It.Is<string>(s => s.Equals("Admin")))).Returns(true);
controller.ControllerContext = controllerContextMock.Object;
var viewResult = controller.Details(1) as ViewResult;
var model = viewResult.Model as BusAcntVm;
Assert.NotNull(model);
Assert.Equal("Company 1", model.CmpnyName);
}
Milox's code seems to make sense but I can't get it to work.
Have I missed something? Is there a change in MVC5 that breaks this code?
SOLUTION:
Implementation of Darin's answer. I now have a Session to write the values against (though the values don't actually get written into it, but that's not needed for the purpose of testing) and the test passes.
Test:
[Fact]
public void AdminGetBusAcntById()
{
var mockMyDb = MockDbSetup.MockMyDb();
var controller = new BusAcntController(mockMy.Object);
var context = new Mock<HttpContextBase>();
var session = new Mock<HttpSessionStateBase>();
var user = new GenericPrincipal(new GenericIdentity("fakeUser"), new[] { "Admin" });
context.Setup(x => x.User).Returns(user);
context.Setup(x => x.Session).Returns(session.Object);
var requestContext = new RequestContext(context.Object, new RouteData());
controller.ControllerContext = new ControllerContext(requestContext, controller);
var viewResult = controller.Details(1) as ViewResult;
var model = viewResult.Model as BusAcntVm;
Assert.NotNull(model);
Assert.Equal("Company 1", model.CmpnyName);
}

In your unit test you have set HttpContext.Current = MockHelpers.FakeHttpContext(); but ASP.NET MVC doesn't use this static property at all. Forget about HttpContext.Current in ASP.NET MVC. It's legacy and unit testing unfriendly (yes, in your case you are using it only inside your unit test, but ASP.NET MVC doesn't use it and is the reason why your code doesn't work).
The whole point is that ASP.NET MVC is working with abstractions such as HttpContextBase, HttpRequestBase, HttpResponseBase, HttpSessionStateBase, ... that you could easily mock in your unit test.
Let's take an example controller:
public class HomeController : Controller
{
public ActionResult Index()
{
if ((this.User.IsInRole("Admin")))
{
return RedirectToAction("Action");
}
this.HttpContext.Session["foo"] = "bar";
return View();
}
}
and how a corresponding unit test might look like by mocking the required abstractions using Moq:
// arrange
var controller = new HomeController();
var context = new Mock<HttpContextBase>();
var session = new Mock<HttpSessionStateBase>();
var user = new GenericPrincipal(new GenericIdentity("john"), new[] { "Contributor" });
context.Setup(x => x.User).Returns(user);
context.Setup(x => x.Session).Returns(session.Object);
var requestContext = new RequestContext(context.Object, new RouteData());
controller.ControllerContext = new ControllerContext(requestContext, controller);
// act
var actual = controller.Index();
// assert
session.VerifySet(x => x["foo"] = "bar");
...
And if you wanted to enter the User.IsInRole("Admin") condition, all you have to do is provide the proper role to the mocked identity.

The way, I would apply Mocking of Sessions using MOQ is as follows.
I would create a base class in UnitTests Project. Structure would be
[TestFixture]
public class BaseClass
{
public Mock<ControllerContext> controllerContext;
public Mock<HttpContextBase> contextBase;
public BaseClass()
{
controllerContext = new Mock<ControllerContext>();
contextBase = new Mock<HttpContextBase>();
controllerContext.Setup(x => x.HttpContext).Returns(contextBase.Object);
controllerContext.Setup(cc => cc.HttpContext.Session["UserId"]).Returns(1);
}
}
Please see : I am returning 1 as session value for UserId in the last line. You can change it as per the requirement.
For easy reference, I would name my TestClass as "ControllerClassTest". So I would inherit ControllerClassTest with BaseClass like this
[TestFixture]
class ControllerClassTest : BaseClass
{
}
Then, In my Test Class, I would initialize ControllerContext within Setup method like this
[SetUp]
public void Setup()
{
controller.ControllerContext = controllerContext.Object;
}
Not to forget, that we have to declare and initialize controller first.
I hope, it helps you