模拟ApplicationUserManager用于单元测试MVC控制器

Question

I would like to know if someone can help me with this.

I am writing unit tests for a specific controller. That controller inherits from a BaseController and that BaseController has this property:

private ApplicationUserManager userManager;
public ApplicationUserManager UserManager 
{ 
    get { return this.userManager ??  this.Request.GetOwinContext().GetUserManager<ApplicationUserManager>(); } 
    set { this.userManager = value; } 
}

The ctor for ApplicationUserManager is:

public ApplicationUserManager(IUserStore<ApplicationUser> store, IIdentityMessageService emailService)
        : base(store)
    {
        this.EmailService = emailService;

        var dataProtectionProvider = Startup.DataProtectionProvider;
        this.UserTokenProvider = new DataProtectorTokenProvider<ApplicationUser>(dataProtectionProvider.Create("ASP.NET Identity"));
    }

This is what I am doing to mock the ApplicatonUserManager class:

var store = new Mock<IUserStore<ApplicationUser>>();
var emailService = new Mock<IIdentityMessageService>();
var applicationUserManager = new Mock<ApplicationUserManager>(store.Object, emailService.Object);
this.targetController.UserManager = applicationUserManager.Object;
var dataprotectionprovided = new Mock<IDataProtectionProvider>();
applicationUserManager.Setup(r => r.UserTokenProvider).Returns(new DataProtectorTokenProvider<ApplicationUser, string>(dataprotectionprovided.Object.Create("ASP.NET Identity")));
this.targetController.UserManager = applicationUserManager.Object;

I have tried to mock this but because this is not virtual property (UserTokenProvider) it does not allow me and I get this exception:

System.NotSupportedException: Invalid setup on a non-virtual (overridable in VB) member: r => r.UserTokenProvider

Can anyone help me with this problem? I just want to mock this in order to test the controller that inherits from a BaseController that has that property..

Thanks

Answer 1

Thanks for your help @bwyn

I have managed to crack it with your suggestion. Just created a new constructor for the ApplicationUserManager like this:

public ApplicationUserManager(IUserStore<ApplicationUser> store) : base(store)
    {
    }

And then the Unit Testing :

var user = new ApplicationUser { User = new User { UserId = 1 } };

        var store = new Mock<IUserStore<ApplicationUser>>(MockBehavior.Strict);
        store.As<IUserStore<ApplicationUser>>().Setup(x => x.FindByIdAsync(It.IsAny<string>())).ReturnsAsync(user);
        this.targetController.UserManager = new ApplicationUserManager(store.Object);

Thank you all!

Answer 2

As pointed out in one of the comments in your answer, creating an additional constructor could lead to another developer using the wrong one.

Can I suggest that instead of this you try the following.

Move the code inside of your original ApplicationUserManager constructor, into a new protected virtual method. Then amend the now empty constructor to call new virtual method.

public class ApplicationUserManager
{
    public ApplicationUserManager(IUserStore<ApplicationUser> store, IIdentityMessageService emailService)
: base(store)
    {
        CalledAfterConstruction();
    }

    protected virtual void CalledAfterConstruction()
    {
        this.EmailService = emailService;

        var dataProtectionProvider = Startup.DataProtectionProvider;
        this.UserTokenProvider = new DataProtectorTokenProvider<ApplicationUser>(dataProtectionProvider.Create("ASP.NET Identity"));
    }
}

Now create a new MockApplicationUserManager class when unit testing that inherits ApplicationUserManager, override the inherited 'CalledAfterConstruction' with just a empty method and you pretty much have things the way you did in your answer.

public class MockClass : ApplicationUserManager
{
    public MockClass(IUserStore<ApplicationUser> store, IIdentityMessageService emailService) : base(store, emailService)
    {
    }

    protected override void CalledAfterContruction()
    {

    }
}

Yes this is a little more complicated but it does stop people from misusing your original class