Wsrtjtyk

I am quite new to MVVMCross and Moq and I need some help with the format of mocking the MvxNavigation Service. I have a call in my code which I want to mock.

I would have thought I could have set the return value by doing something along the lines of:

 _naviageService.Setup(n => n.Navigate<PlaceSelectViewModel, Place, Place>(It.IsAny<Place>())).Returns(returnPlace);

but this does not compile. I have tried looking in the Moq quick start and MVVMCross example but can’t seem to find what I want. Please find complete sample below as requested: Tnx

public class FooClass

{

    IMvxNavigationService _navigationService;



    public IMvxAsyncCommand SelectPlaceCommand { get; }



    public FooClass(IMvxNavigationService navigationService)

    {

        _navigationService = navigationService;

        SelectedplaceCommand = new MvxAsyncCommand(SelectPlace);

    }



    async Task SelectPlace()

    {



        var place = await _navigationService.Navigate<PlaceSelectViewModel, Place, Place>(new Place());



        // Do somehting with place

    }



}



[TestFixture]

public class FooTests : MvxIoCSupportingTest

{

    Mock<IMvxNavigationService> _navigationService;

    FooClass _foo;



    [SetUp]

    public void SetUp()

    {

        base.Setup();



        _navigationService = new Mock<IMvxNavigationService>();

        _foo = new FooClass(_navigationService.Object);

    }



    [Test]

    public async Task DoSomthing_NavigatesToPlaceSelectViewModel()

    {

        //Arrange





        var returnPlace = new Place { MapTitle = "New Place" };



        await _navigationService.Setup(n => n.Navigate<PlaceSelectViewModel, Place>(It.IsAny<Place>())).Returns(returnPlace);  // ** This is incorrect syntax and does not complile



        //Act

        await _foo.SelectPlaceCommand.ExecuteAsync();



        //Assert

        _navigationService.Verify(s => s.Navigate<PlaceSelectViewModel, Place, Place>

                                  (It.IsAny<Place>(),

                                  null,

                                   It.IsAny<CancellationToken>()));

    }



}

As this issue from the Moq repository explains, you can't just skip optional parameters.

This is kind of a workaround if you are not using all parameters in your Navigate call (or more accurate, if you don't care about them):

_naviageService.Setup(n => n.Navigate<PlaceSelectViewModel, Place, Place>(

        It.IsAny<Place>(), 

        It.IsAny<IMvxBundle>(), 

        It.IsAny<CancellationToken>())

    ).Returns(returnPlace);