public void ProspectGetHiddenProspectUrlFormedCorrectly() { var mockDataSource = MockRepository.GenerateMock<IWebClient>(); var expectedUrl = Constants.ListHiddenProspectsUrl; // Arrange mockDataSource .Stub(x => x.UploadString( Arg<string>.Is.Anything, // uri Arg<string>.Is.Anything, // method Arg<string>.Is.Anything, // content-type Arg<string>.Is.Anything // data )) .Return(string.Empty); // Act var target = new Prospects(accessToken: Constants.AccessToken) { UserWebClient = mockDataSource }; target.GetHiddenProspect(); // Assert mockDataSource.AssertWasCalled(c => c.UploadString( Arg<string>.Matches(actualUrl => actualUrl == expectedUrl), Arg<string>.Is.Anything, Arg<string>.Is.Anything, Arg<string>.Is.Anything)); }