How to resolve "named type" in NSubstitute?

Question

I am using IUnityContainer for Registering the types for resolving later. I have registered the types as below:

// Register a "named type" mapping
container.RegisterType<IProcessHelper, FirstResponseHelper>("FirstResponseHelper");
container.RegisterType<IProcessHelper, SecondResponseHelper>("SecondResponseHelper");

Hence, I could able to use as below in one of my constructor:

     public Finish(
        IUnitOfWork unitOfWork   ,
        ILog logger, 
        ..........
        [Dependency("FirstResponseHelper")] IProcessHelper firstResponseHelpe,
        [Dependency("SecondResponseHelper")] IProcessHelper secondResponseHelper
      )
     {
         .........
        _firstResponseHelpe = firstResponseHelper;
        _secondResponseHelper = secondResponseHelper;
     }

...and would like to get it resolved using Substitute, something-like "below". But by passing the "name" => "FirstResponseHelper" is not allowed in Substitute! :(

// Trying to resolve in UnitTest, looks like below (passing name)
IProcessHelper firstResponseHelper = Substitute.For<IProcessHelper>("FirstResponseHelper")
IProcessHelper secondResponseHelper = Substitute.For<IProcessHelper>("SecondResponseHelper")

I need to call a method from FirstResponseHelper & SecondResponseHelper, from my UnitTest (MSTest). Hence, I need to get it resolved using Substitute.For<> for the "named type" interface.

Hi @Lakshminarayanan, maybe consider renaming the question to "How to resolve “named type” in Unity container?". I don't think this is specific to NSubstitute, but for rather for injecting any named instance. — David Tchepak, Aug 07 '17 at 01:33

score 1 · Answer 1 · edited Aug 08 '17 at 01:31

I'm assuming that you want to register a Substitute as named registration so that you can resolve Finish. If that is the case then you can use an InjectionFactory to return the substitute:

container.RegisterType<IProcessHelper>("FirstResponseHelper",
    new InjectionConstructor(c => Substitute.For<IProcessHelper>()));

container.RegisterType<IProcessHelper>("SecondResponseHelper",
    new InjectionConstructor(c => Substitute.For<IProcessHelper>()));

As an aside I wouldn't use the [DependencyAttribute] and instead remove those attributes and define an InjectionConstructor that passes in the correct dependencies:

container.RegisterType<Finish>(
    new InjectionConstructor(
        new ResolvedParameter<IUnitOfWork>(),
        new ResolvedParameter<ILog>(),
        new ResolvedParameter<IProcessHelper>("FirstResponseHelper"),
        new ResolvedParameter<IProcessHelper>("SecondResponseHelper")));

or an InjectionFactory that does something similar:

container.RegisterType<Finish>(
    new InjectionFactory(c =>
    {
        return new Finish(c.Resolve<IUnitOfWork>(),
            c.Resolve<ILog>(),
            c.Resolve<IProcessHelper>("FirstResponseHelper"),
            c.Resolve<IProcessHelper>("SecondResponseHelper")
    }));

How to resolve "named type" in NSubstitute?

1 Answers1