How to get access to parameters value in Returns() using FakeItEasy?

Question

I have an interface to a factory used to create some data objects.

interface IFactory {     IData Create (string name, string data); }  interface IData {     // .... }  class Data : IData {     public Data (string name, string data)     {         // .....     } } 

I need to create a mock factory to pass to another module and this module will use this mock to create data.

For a quick example, a simple module looks like:

class QuickModule {     private readonly IFactory _factory;      public QuickModule (IFactory factory)     {         _factory = factory;     }      public IEnumerable<IData> GetData ()     {         yield return _factory.Create ("name1", "abc");         yield return _factory.Create ("name2", "def");     } } 

So, the factory is called two times with two sets of parameters.

Using Moq, this is easy:

var factoryMock = new Mock<IFactory> (); factoryMock.Setup (x => x.Create (It.IsAny<string> (), It.IsAny<string> ()))                     .Returns ((string name, string data) => new Data (name, data)); var module = new QuickModule (factoryMock.Object); var list = module.GetData (); 

However using FakeItEasy this would not seem to be possible:

var factory = A.Fake<IFactory> (); A.CallTo (() => factory.Create (A<string>.Ignored, A<string>.Ignored))               .Returns (new Data (???, ???)); var module = new QuickModule (factory); var list = module.GetData (); 

How can I access the parameters values?

Answer 1

Ok, it would seem that ReturnsLazily() is the answer.

So here's what I did:

var factory = A.Fake<IFactory> (); A.CallTo (() => factory.Create (A<string>.Ignored, A<string>.Ignored))               .ReturnsLazily ((string name, string data) => new Data (name, data)); var module = new QuickModule (factory); var list = module.GetData (); 

Is this the recommended way or is there another?