I am new to nSubstitute. And I am writing test method for my controller class. I have a TestMethod called GetDefaultStateTest() which having Substitute class as shown below
[TestMethod]
public void GetDefaultStateTest()
{
var _GetDefaultState = Substitute.For<CustomerController>(ICustomer cus);
Assert.IsNotNull(_GetDefaultState.GetDefaultState());
}
Because my controller class having parameterized constructor as below.
public class CustomerController : Controller
{
private readonly ICustomer _customer;
public CustomerController(ICustomer customer)
{
_customer = customer;
}
public string GetDefaultState()
{
// Get default state from settings table
List<tblSettings> settings = new List<tblSettings>();
// Calling service method GetSettings
settings = _customer.GetSettings();
var defaultState = from setting in settings
where setting.Desc == "DefaultState"
select setting.Settings;
string strState = "";
foreach (var oState in defaultState)
{
strState = oState;
break;
}
return strState;
}
}
While run the test method, it raise null reference issue. Because of parameter ICustomer is null
var _GetDefaultState = Substitute.For<CustomerController>(ICustomer cus);
How to resolve this problem.
If you are testing your controller class then you do not want to substitute for it, you want to use a real one (otherwise you'd just be testing a fake object "works" :)). Where you may want to substitute is for that class's dependencies, in this case, ICustomer.
[TestMethod]
public void GetDefaultStateTest()
{
var customer = Substitute.For<ICustomer>();
var controller = new CustomerController(customer);
Assert.IsNotNull(controller.GetDefaultState());
}
You may then want to fake out the ICustomer.GetSettings() method so you can test what your controller does with that data:
[TestMethod]
public void GetDefaultStateTestFromSettings()
{
var customer = Substitute.For<ICustomer>();
customer.GetSettings().Returns(somethingSensible);
var controller = new CustomerController(customer);
Assert.AreEqual(expectedDefaultState, controller.GetDefaultState());
}
As an aside, sometimes it makes more sense to use real objects (say, a real implementation of ICustomer) rather than substitutes. This will depend on how well-defined the interactions with the dependencies are, where you want to define the boundaries of your system under test, and how much confidence the test gives you that the system under test is working correctly. Or put more simply, whatever makes it easy and reliable to test. :)
Hope this helps.
Related
I can make it work, but I want to know what the best practice is and why. I have a Controller, a Model, and a Repository and now I want to Unit Test the Controller. I am just writing a simple test to ensure that the correct view is being returned.
This is my method in the controller:
public ActionResult Selections(SelectionsViewModel model)
{
for (int i = 0; i < model.Sends.Count; i++)
{
Send send = new Send(new SendService(new Database().GetConnectionString()))
{
SendID = model.Sends[i].SendID,
Title = model.Sends[i].Title,
Subject = model.Sends[i].Subject,
SentDate = model.Sends[i].SentDate,
TimesViewed = model.Sends[i].TimesViewed,
Include = model.Sends[i].Include,
Exclude = model.Sends[i].Exclude
};
send.UpdateIncludeExclude();
}
return View(model);
}
Here is my GetConnectionString() method in the Database class that is being sent via my SendService constructor.
public string GetConnectionString()
{
return System.Configuration.ConfigurationManager.ConnectionStrings["DEVConnectionString"].ToString();
}
And lastly, my unit test:
[Test]
public void TestAssignmentSelections()
{
var obj = new AssignmentController();
var actResult = obj.Selections() as ViewResult;
NUnit.Framework.Assert.That(actResult.ViewName, Is.EqualTo("Selections"));
}
Now, my unit test fails, and I get why. My unit test project has no access to the web.config of the project I am testing where my connection string resides.
I've done some research, and apparently just adding a web.config to my unit test project and putting the connection string in there as well will make it work.. but that seems like a hack.
What's the best way to go about this? Is there another way to write my code to accommodate for this?
You want to make your controller unit testable ? Don't do this.
new SendService(
With this code,you are hardcoding your concrete service implementation & your data access code implementation. In your unit test, you should not be really accessing the data from your database. Instead you should be providing a mock data access implementation.
Here comes interfaces, you need to create an interface for your SendService.
public interface ISendService
{
void SomeMethod();
}
now your SendService will be a concrete implementation of this interface
public class SendService : ISendService
{
public void SomeMethod()
{
// Do something
}
}
Now update your controller to have a constructor where we will inject an implementation of ISendService.
public class YourController : Controller
{
private ISendService sendService;
public YourController(ISendService sendService)
{
this.sendService = sendService;
}
public ActionResult YourActionMethod()
{
// use this.sendService.SomeMethod();
}
}
And you may use some dependency injection frameworks to tell the MVC framework which implementation of the interface to use when the code runs. If you are using MVC6,It has an inbuilt dependency injection provider you can use. So go to your Startup class and in your ConfigureServices method, you can map an interface to a concrete implementation.
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
services.AddTransient<ISendService, SendService>();
}
}
If you are in a previous version of MVC, You may consider DI frameworks like Unity,Ninject etc. You can do the same approach for your Data access later / Service layers. ie: Create an interface for data access and inject that to your SendService.
public Interface IDataAccess
{
string GetName(int id);
}
and an implementation which uses your specific data access code/ORM
public class EFDataAccess : IDataAccess
{
public string GetName(int id)
{
// return a string from db using EF
}
}
So now your Service class will be
public class SendService : ISendService
{
private IDataAccess dataAccess;
public SendService(IDataAccess dataAccess)
{
this.dataAccess=dataAccess;
}
// to do : Implement methods of your ISendService interface.
// you may use this.dataAccess in those methods as needed.
}
In your unit tests, you can create a mock implementation of your interfaces which returns static data instead of accessing the database.
For example, If you are using Moq mocking framework, you can do this.
var m = new Mock<IDataAccess>();
var m.Setup(s=>s.GetName(It.IsAny<int>())).Returns("Test");
var s = new SendService(m);
var result= s.SomeMethod();
I have a Controller named "UserController" with method named "Invite". My controller has the following override method:
DBRepository _repository;
protected override void Initialize(System.Web.Routing.RequestContext requestContext)
{
base.Initialize(requestContext);
_repository = new DBRepository();
}
so, this method is called each time when UserController class is created.
My method "Invite" has the following lines:
var startTime = _repository.Get<AllowedTime>(p => p.TimeID == selectTimeStart.Value);
but when I try to call this method via Unit method:
[TestMethod()]
[UrlToTest("http://localhost:6001/")]
public void InviteTest()
{
UserController target = new UserController(); // TODO: Initialize to an appropriate value
int? selectTimeStart = 57;
int? selectTimeEnd = 61;
Nullable<int> selectAttachToMeeting = new Nullable<int>(); // TODO: Initialize to an appropriate value
int InvitedUserID = 9; // TODO: Initialize to an appropriate value
UserInviteModel model = new UserInviteModel();
model.Comment = "BLA_BLA_BLA";
ActionResult expected = null; // TODO: Initialize to an appropriate value
ActionResult actual;
actual = target.Invite(selectTimeStart, selectTimeEnd, selectAttachToMeeting, InvitedUserID, model);
Assert.AreEqual(expected, actual);
Assert.Inconclusive("Verify the correctness of this test method.");
}
I got an error "Reference is not set...". I understand why it happens (_repository is null because Initialize method is not called in my case, but how to do it correctly?
If you expect DBRepository to actually perform the Get from your backing data store during your test, you could change your _repository field to be a Lazy<DBRepository>, that gets initialized upon first use. (I'm assuming it's being newed up in the Initialize method rather than the constructor because it relies on the current request context?)
If you want this to be a true unit test, it shouldn't test the DBRepository class at all: you should be programming to an interface that you can mock up. Additionally, you need to make it so that your DBRepository comes from someplace where it can be provided by the test case. You could have it built by a factory or provided as a singleton, and the test case could set up the factory or singleton to provide a mocked object ahead of time. However, the best approach would be to use Dependency Injection, so you can provide a fake/mock IDBRepository when you construct the new UserController().
I have a method which looks like the one below
public List<Rajnikanth> GetRajnis()
{
string username = Utility.Helpers.GetLoggedInUserName();
return _service.GetRajni(username);
}
Utility.Helper is a static class,
public static class Helpers
{
public static String GetLoggedInUserName()
{
string username = "";
if (System.Web.HttpContext.Current.User.Identity.IsAuthenticated)
{
username = ((System.Web.Security.FormsIdentity)HttpContext.Current.User.Identity).Ticket.Name;
}
return username;
}
}
I want to test : GetRajnis()
I want to mock : GetLoggedInUserName()
So my test method looks something like...
[TestMethod]
public void TestGetRajnis()
{
SomeController s = new SomeController(new SomeService());
var data = s.GetRajnis();
Assert.IsNotNull(data);
}
how do I mock the static method GetLoggedInUserName() ?
The Simplest Approach: Override the return value
If you are looking to mock a return value, then this is very simple. You can modify the Utility.Helper class to include a property called OverrideLoggedInUserName. When someone calls GetLogedInUserName(), if the override property is set, it is returned, otherwise the normal code to get the value from the HttpContext is used to get the return value.
public static class Helper
{
// Set this value to override the return value of GetLoggedInUserName().
public static string OverrideLoggedInUserName { get; set; };
public static string GetLoggedInUserName()
{
// Return mocked value if one is specified.
if ( !string.IsNullOrEmpty( OverrideLoggedInUserName ) )
return OverrideLoggedInUserName;
// Normal implementation.
string username = "";
if ( System.Web.HttpContext.Current.User.Identity.IsAuthenticated )
{
username = ( (System.Web.Security.FormsIdentity)HttpContext.Current.User.Identity ).Ticket.Name;
}
return username;
}
}
This will effectively allow you to override the return value, which technically isn't a mock--it's a stub (according to the excellent article Mocks Aren't Stubs by Martin Fowler). This allows you to stub a return value, but won't allow you to assert whether the method was called or not. Anyhow as long as you only want to manipulate the return value this works fine.
Here is how you would use this in a test.
[ TestMethod ]
public void TestGetRajnis()
{
// Set logged in user name to be "Bob".
Helper.OverrideLoggedInUserName = "Bob";
SomeController s = new SomeController( new SomeService() );
var data = s.GetRajnis();
// Any assertions...
}
This design does have one drawback. Because it's a static class, if you set the override value, it remains set until you un-set it. So you must remember to re-set it to null.
A Better Approach: Inject the dependency
A better approach may be to create a class that retrieves the logged in user name, and pass it into the constructor of SomeController. We call this dependency injection. This way, you can inject a mocked instance into it for testing, but pass the real instance (that gets the user from the HttpContext) when not testing. This is a much cleaner and clearer approach. Plus, you can leverage all the power of whatever mocking framework you are using, since they are designed specifically to handle this approach. Here is what that would look like.
// Define interface to get the logged in user name.
public interface ILoggedInUserInfo
{
string GetLoggedInUserName();
}
// Implementation that gets logged in user name from HttpContext.
// This class will be used in production code.
public class LoggedInUserInfo : ILoggedInUserInfo
{
public string GetLoggedInUserName()
{
// This is the same code you had in your example.
string username = "";
if ( System.Web.HttpContext.Current.User.Identity.IsAuthenticated )
{
username = ( (System.Web.Security.FormsIdentity)HttpContext.Current.User.Identity ).Ticket.Name;
}
return username;
}
}
// This controller uses the ILoggedInUserInfo interface
// to get the logged in user name.
public class SomeController
{
private SomeService _service;
private ILoggedInUserInfo _userInfo;
// Constructor allows you inject an object that tells it
// how to get the logged in user info.
public SomeController( SomeService service, ILoggedInUserInfo userInfo )
{
_service = service;
_userInfo = userInfo;
}
public List< Rajnikanth > GetRajnis()
{
// Use the injected object to get the logged in user name.
string username = _userInfo.GetLoggedInUserName();
return _service.GetRajni( username );
}
}
And here is a test using Rhino Mocks to inject a stub object into the controller.
[ TestMethod ]
public void TestGetRajnis()
{
// Create a stub that returns "Bob" as the current logged in user name.
// This code uses Rhino Mocks mocking framework...
var userInfo = MockRepository.GenerateStub< ILoggedInUserInfo >();
userInfo.Stub( x => x.GetLoggedInUserName() ).Return( "Bob" );
SomeController s = new SomeController( new SomeService(), userInfo );
var data = s.GetRajnis();
// Any assertions...
}
The disadvantage here is that you can't just call Helper.GetLoggedInUserName() from anywhere in your code, because it's no longer static. However, you no longer have the need to reset the stubbed username every time you finish a test. Because it's not static, it it automatically reset. You just recreate it for the next test and set a new return value.
I hope this helps.
Get rid of the static class if you are looking for testability. A simple fix for now would be to create a wrapper around the static class. Unless you use something like TypeMock or something equally as powerful, then you cannot alter the logic of a static class. Nor do I suggest it. If you have to stub a static class, it probably should not be a static class.
public class StaticWrapper
{
public virtual String GetLoggedInUserName()
{
Utility.Helpers.GetLoggedInUserName();
}
}
I'm starting with unit testing in the asp.net mvc 4 framework.
I got a repository with basic crud methods and a save method. When I create a unit test I create a test repository and test if e.g. a item to the collection is added. That all goes smoothly but I cannot test if the save method is hit.
I tried to add a boolean property to the test repository which will be set to true if .save() is hit. But then I need to change the interface, and also the database repository. Which is in my opinion neither practical nor best practice.
What is the best method to test this? Thank you in advance for your answer.
My code:
the fake repository:
public class TestUserRepository : IUserManagementRepository
{
/// <summary>
/// entries used used for testing
/// </summary>
private List<User> _entities;
/// <summary>
/// constructor
/// </summary>
public TestUserRepository()
{
_entities = new List<User>();
_entities.Add(new User
{
Id = 1,
InsertDate = DateTime.Now,
LastUpdate = DateTime.Now,
Username = "TestUserName",
Password = "TestPassword"
});
}
...
public void Create(User task)
{
_entities.Add(task);
}
public void Save()
{
//do nothing
}
}
the controller to test:
[HttpPost]
public ActionResult Create(User user)
{
if (ModelState.IsValid)
{
_repository.Create(user);
_repository.Save();
return RedirectToAction("Index");
}
else
{
return View(user);
}
}
and the test
[TestMethod()]
public void CreateTest()
{
IUserManagementRepository repository = new TestUserRepository();
UserController controller = new UserController(repository);
User user = new User { Username = "UnitTestUserName", InsertDate = DateTime.Now, LastUpdate = DateTime.Now, Password = "Password" };
ActionResult actionResult = controller.Create(user);
User returnedUser = repository.FindBy(u => u.Username == "UnitTestUserName").First<User>();
Assert.IsNotNull(actionResult);
Assert.AreEqual(user, returnedUser);
}
You must be careful not to write a bunch of unit tests that just test your test repository.
Consider the following scenario:
You have a service method, that is supposed to add an item to your repository.
Your unit test calls this method, and you should verify that the appropriate "AddX" method was called on the repository.
This is a valid unit test scenario, to test it you can use your test repository. Since it is your test object, you have full control over it. You can expose properties such as "AddXMethodCallCount" or something similar.
Over time you will find yourself writing a lot of test code that is pretty much boilerplate. The alternative, which I strongly recommend, is to use a mocking framework:
https://stackoverflow.com/questions/37359/what-c-sharp-mocking-framework-to-use
It takes some getting used to, but once you get it, it will speed up your unit testing significantly.
If you don't want to use mocking yet, but want to still achieve your goal of verifying whether or not Save() is called, I would suggest just adding a publicly exposed SaveMethodCallCount property:
public class TestUserRepository : IUserManagementRepository
{
...
public SaveMethodCallCount {get; set;}
...
public void Save()
{
SaveMethodCallCount++;
}
}
This works, because in your unit test you can actually say:
TestUserRepository repository = new TestUserRepository();
The UserController does not care, as long as the passed in parameter implements the IUserManagementRepository interface. The controller interacts with the repository object through the interface, but the unit test does not have to, and the TestUserRepository, being a test class, is allowed to have much more functionality, that does not have to be exposed through the interface.
So your test could look something like:
[TestMethod()]
public void CreateTest()
{
TestUserRepository repository = new TestUserRepository();
UserController controller = new UserController(repository);
User user = new User { Username = "UnitTestUserName", InsertDate = DateTime.Now, LastUpdate = DateTime.Now, Password = "Password" };
ActionResult actionResult = controller.Create(user);
User returnedUser = repository.FindBy(u => u.Username == "UnitTestUserName").First<User>();
Assert.IsNotNull(actionResult);
Assert.AreEqual(user, returnedUser);
Assert.AreEqual(1, repository.SaveMethodCallCount);
}
To make my example complete, let me show you what this would look like if you used a mocking framework, like Moq. You can see some more examples here. The example test method uses Moq and Arrange/Act/Assert, and tests only one thing - that Save() is called when Create() is called.
[TestMethod()]
public void Test_SaveCalledWhenCreateCalled()
{
// Arrange
// First, instead of creating an instance of your test class, you create a mock repository.
// In fact, you don't need to write any code, the mocking framework handles it.
var mockRepository = new Mock<IUserManagementRepository>();
// and pass the mock repository (which implements the IUserManagementRepository) to your controller
UserController controller = new UserController(mockRepository);
// Act
ActionResult actionResult = controller.Create(user);
// Assert
// see how easy it is to do with a mocking framework:
mockRepository.Verify(rep => rep.Save(), Times.AtLeastOnce());
}
I am using ASP.NET MVC 3, MVCContrib, NUnit and Rhino Mocks. I have posted this but could not get an answer. People are focusing more on my coding that helping me get a decent answer to get this test to pass.
I am trying to test my Edit view. I'm not sure how to code the test for the view. It is a strongly typed view of type NewsEditViewData.
When the view loads, it gets a news item's data by ID from the news service. So in my test I created a stub of the news service:
var id = 1;
var news = new News();
newsServiceStub
.Stub(x => x.FindById(id))
.Return(news);
Now I need to map this news item to NewsEditViewData. I have a mapper (AutoMapper) that does this for me, and in my test I did the following:
newsMapperStub
.Stub(x => x.Map(news, typeof(News), typeof(NewsEditViewData)))
.Return(newsEditViewData);
I'm not sure if I am on the right track so far?
Then I have the following piece of code:
// Act
var actual = sut.Edit(id);
Don't work from my code, I want an answer following best practices. So what all do I need to check for in my assert part? Do I need to also check that a record was returned? I was thinking in the lines of something like:
actual
.AssertViewRendered()
.WithViewData<NewsEditViewData>()
.ShouldBe(newsEditViewData);
This fails. Can someone please help me rewrite this test so that it passes. I want it to check all that needs to be checked.
Here is the full test:
[Test]
public void Edit_should_render_Edit_view()
{
// Arrange
var id = 1;
var news = new News();
var newsEditViewData = new NewsEditViewData();
newsServiceStub
.Stub(x => x.FindById(id))
.Return(news);
newsMapperStub
.Stub(x => x.Map(news, typeof(News), typeof(NewsEditViewData)))
.Return(newsEditViewData);
// Act
var actual = sut.Edit(id);
// Assert
actual
.AssertViewRendered()
.WithViewData<NewsEditViewData>()
.ShouldBe(newsEditViewData);
}
UPDATE 2011-02-14:
In my NewsController I have the following:
private INewsService newsService;
private IMapper newsMapper;
public NewsController(INewsService newsService)
{
Check.Argument.IsNotNull(newsService, "newsService");
this.newsService = newsService;
newsMapper = new NewsMapper(); // TODO: Use dependency injection
}
The action method looks like this:
public ActionResult Edit(int id)
{
Check.Argument.IsNotZeroOrNegative(id, "id");
var news = newsService.FindById(id);
var newsEditViewData = (NewsEditViewData)newsMapper.Map(news, typeof(News), typeof(NewsEditViewData));
return View(newsEditViewData);
}
The error that I am getting in NUnit is:
MyProject.Web.UnitTests.Controllers.NewsControllerTests.Edit_RenderView_EditView:
MvcContrib.TestHelper.AssertionException : was MyProject.Web.Common.ViewData.NewsEditViewData but expected MyProject.Web.Common.ViewData.NewsEditViewData
You haven't shown none of your controller, repository, models. It's a question that is close to impossible to answer without this information. So lets start guessing. You have a model and a view model:
public class News { }
public class NewsEditViewData { }
I am leaving them without any properties for the purpose of this post. Then you probably have a service which is responsible for retrieving and saving your model (the view model should never appear as in/out argument of your service layer). The service should never know about the view model:
public interface INewsService
{
News FindById(int id);
void CreateNews(News news);
}
Then you probably have a mapper:
public interface IMapper
{
object Map(object source, Type sourceType, Type destinationType);
}
And finally I suppose that you have a controller that you are trying to test:
public class NewsController : Controller
{
private readonly INewsService _newsService;
private readonly IMapper _newsMapper;
public NewsController(INewsService newsService, IMapper newsMapper)
{
_newsService = newsService;
_newsMapper = newsMapper;
}
public ActionResult Edit(int id)
{
// WARNING: Meaningless action ahead as it retrieves some
// model from the service and passes this model to
// the service back again for update. In the meantime
// the model is converted to a view model using a mapper
// and passed to the view. So totally meaningless in a real
// application but let's consider for the purpose of this demonstration
var news = _newsService.FindById(id);
_newsService.CreateNews(news);
var newsEditViewData = (NewsEditViewData)_newsMapper.Map(news, typeof(News), typeof(NewsEditViewData));
return View(newsEditViewData);
}
}
OK, up until here it is you that should have provided this information.
And now I can start answering your question about the unit test which might look like this:
[Test]
public void Edit_should_fetch_news_model_from_service_given_an_id_parameter_create_news_and_pass_a_viewmodel_to_the_view()
{
// arrange
// TODO : move this part in the initialization section
// of your unit test to avoid repeating it on each method
var newsServiceStub = MockRepository.GenerateStub<INewsService>();
var newsMapperStub = MockRepository.GenerateStub<IMapper>();
var sut = new NewsController(newsServiceStub, newsMapperStub);
new TestControllerBuilder().InitializeController(sut);
var news = new News();
var id = 123;
var newsEditViewData = new NewsEditViewData();
newsServiceStub
.Stub(x => x.FindById(id))
.Return(news);
newsMapperStub
.Stub(x => x.Map(news, typeof(News), typeof(NewsEditViewData)))
.Return(newsEditViewData);
// act
var actual = sut.Edit(id);
// assert
actual
.AssertViewRendered()
.WithViewData<NewsEditViewData>()
.ShouldBe(newsEditViewData);
newsServiceStub.AssertWasCalled(x => x.CreateNews(news));
}