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Rhino mocks AssertWasCalled does not work

I wrote the following test case to illustrate my problem using Rhino Mocks:
[TestClass]
public class Tester
{
public class TestList<T> : List<T>
{
public override bool Equals(object obj)
{
// obj is an empty list here??
return base.Equals(obj);
}
}
public interface IStubbedInterface
{
void DoSomethingWithList(TestList<int> list);
}
public class ClassToTest
{
public IStubbedInterface TheStub { get; set; }
public void Run()
{
var list = new TestList<int> { 1, 2 };
TheStub.DoSomethingWithList(list);
list.Clear();
}
}
public bool Match(TestList<int> arg)
{
// Here arg is an empty list??
return arg == new TestList<int> { 1, 2 };
}
[TestMethod]
public void Test()
{
var classToTest = new ClassToTest();
classToTest.TheStub = MockRepository.GenerateMock<IStubbedInterface>();
classToTest.Run();
classToTest.TheStub.AssertWasCalled(
x => x.DoSomethingWithList(new TestList<int>() { 1, 2 }));
//x => x.DoSomethingWithList(Arg<TestList<int>>.Matches(arg => Match(arg))));
}
}
The test case will fail on the AssertWasCalled() line, no matter if I compare the list directly or using the Arg<>.Matches(..) syntax. I also tried with MockRepository.GenerateStub<>(..) instead of GenerateMock<>(..), which also fails. It fails because of the list.Clear(); line after calling DoSomethingWithList(), which results in the list also being empty at the time of AssertWasCalled(). Is this a bug with RhinoMocks? I would have assumed that RhinoMocks would record a snapshot of the argument somehow when the asserted function was called, but it looks like RhinoMocks keeps using the same object?
In the real case where I encountered this problem the argument of the function I was testing was wrapped in a using() statement, which lead to the same effect of AssertWasCalled not being able to test the arguments passed.

Looks like using the Expect()/VerifyAllExpectations() pattern works better for this test scenario. Changing the test case to the below code will pass.
This is rather unfortunate as I much prefer using AssertWasCalled(), however as it stands it is rather unreliable.
[TestMethod]
public void Test()
{
var classToTest = new ClassToTest();
classToTest.TheStub = MockRepository.GenerateMock<IStubbedInterface>();
classToTest.TheStub.Expect(
x => x.DoSomethingWithList(new TestList<int>() { 1, 2 }));
classToTest.Run();
classToTest.TheStub.VerifyAllExpectations();
}

How to test function that has objects as parameters in XUnit?

I have a simple function that takes Client and Supplier data and then calculates tax based on where they live and other information:
static int CountTax(Supplier tiek, Client kl, bool same_country)
{
if ( !tiek.is_PVM_payer)
return 0;
else
{
if (!kl.EU)
return 0;
else
{
if (same_country)
return kl.x;
else
{
if (kl.is_PVM_payer)
return 0;
else
return kl.x;
}
}
}
}
Now I am required to write tests for this function. It is the first time I am encountering tests. I am using XUnit testing. And my test class looks like this:
using System;
using Xunit;
namespace CountTax_tests
{
public class UnitTest1
{
[Theory]
[InlineData(typeof(Client))]
public void Tax_is_0()
{
// arrange
int expectedVal = 0;
int actualVal;
/// act
actualVal = MyProgram.MyprogramCode.CountTax(supplier, client, same_country);
// assert
Assert.Equal(expectedVal, actualVal);
}
[Fact]
public void PVM_is_x()
{
int expectedVal = x;
int actualVal;
actualVal = MyProgram.MyprogramCode.CountTax(supplier, client, same_country);
Assert.Equal(expectedVal, actualVal);
}
}
}
But how do I pass my Client and Supplier parameters to that test? Please help me and lead on a path because I am completely new and nothing is clear to me even after many tutorials...
Maybe I have to use [Theory]? Or maybe [Fact]? Or maybe it is impossible to pass classes as parameters?
Also, [InlineData(typeof(Client))] is being underlined in red and is not working.

Mocking an object initialised inside a method under test

I am trying to test a class which instatiates another class within it. It is the instatinated class call I want to mock.
Is this possible or is they a way around it/ simpler way I am missing?
Below I have written up a simpler example which still has the same problemts as my main code.
public interface my_interface
{
int returns_25();
}
public class class_i_want_to_mock : my_interface
{
public int returns_25()
{
// TEST SHOULD FAIL SO NEED MOCK TO PASS THE CASE
return 7645745;
}
}
In another namespace (it has access):
public class class_to_test
{
public static int returns_25()
{
class_i_want_to_mock _tempClass= new class_i_want_to_mock ();
// Will return 7645745 unless moq changes return value
int _temp_int = _tempClass.returns_25()
return _temp_int;
}
}
My test (which fails):
[Test]
public void test_returns_25()
{
// Mock
Mock<my_interface> myMock = new Mock<my_interface>();
myMock.Setup(m => m.returns_25()).Returns(25);
// Act
int return_number = class_to_test.returns_25();
// Assert
Assert.AreEqual(25, return_number);
}

Here is working code thanks to the injection idea from JSteward above.
Code is in same order
public interface my_interface
{
int returns_25();
}
public class class_i_want_to_mock : my_interface
{
public int returns_25()
{
// TEST SHOULD FAIL SO NEED MOCK TO PASS THE CASE
return 7645745;
}
}
Next class, notice the injection of the interface
public class class_to_test
{
public static int returns_25(my_interface _temp_interface)
{
// Will return 7645745 unless moq changes return value
int _temp_int = _temp_interface.returns_25()
return _temp_int;
}
}
And the test. Note the object of the Mock class has to be used (myMock.Object)
[Test]
public void test_returns_25()
{
// Mock
Mock<my_interface> myMock = new Mock<my_interface>();
myMock.Setup(m => m.returns_25()).Returns(25);
// Act
int return_number = class_to_test.returns_25(myMock.Object);
// Assert
Assert.AreEqual(25, return_number);
}

Limiting Scope of UnitTest using Rhino stubs

I'm working on a unit test for a service method, that has dependencies. Simplified:
public class ConditionChecker
{
private SqlConnection _connection;
public bool CanDoSomething()
{
return _connection.State == ConnectionState.Open;
}
}
public class A
{
public ConditionChecker Checker { get; set; }
public bool CanInvokeA()
{
return Checker.CanDoSomething();
}
}
[TestClass]
public class ATests
{
[TestMethod]
public void TestCanInvokeA()
{
// arrange
A a = new A();
ConditionChecker checker = MockRepository.GenerateStub<ConditionChecker>();
checker.Stub(x => x.CanDoSomething()).Return(true);
a.Checker = checker;
// act
bool actual = a.CanInvokeA();
// assert
Assert.AreEqual(true, actual);
}
}
What I want is to completely bypass the implementation of ConditionChecker.CanDoSomething, which is why I stub the call, still I run into a null reference Exception during my test, since the _connection member is not set. What am I doing wrong here?

You just mark your method as virtual, it will work:
public virtual bool CanDoSomething()
{
}
Since behind the scene Rhino Mock will create a dynamic proxy for ConditionChecker, so you need to mark virtual to allow Rhino Mock to override it.

Rhinomocks - Mocking delegates

public interface IServiceInvoker
{
R InvokeService<T, R>(Func<T, R> invokeHandler) where T : class;
}
public class MediaController : Controller
{
private IServiceInvoker _serviceInvoker;
public MediaController(IServiceInvoker serviceInvoker)
{
_serviceInvoker = serviceInvoker;
}
public JsonResult GetAllMedia()
{
var media = _serviceInvoker.InvokeService<IMediaService, List<MediaBase>>(proxy => proxy.GetAllMediaInJson());
JsonResult jsonResult = new JsonResult();
jsonResult.Data = media;
jsonResult.JsonRequestBehavior = JsonRequestBehavior.AllowGet;
return jsonResult;
}
[TestClass]
public class MediaControllerTests
{
[TestMethod]
public void GetAllMedia()
{
JsonResult data;
var serviceInvoker = MockRepository.GenerateStub<IServiceInvoker>();
var media = CreateSeveralMedia();
serviceInvoker.Stub(c => c.InvokeService<IMediaService, List<MediaBase>>(p => p.GetAllMediaInJson())).Return(media);
data = new MediaController(serviceInvoker).GetAllMedia();
serviceInvoker.VerifyAllExpectations();
Assert.IsNotNull(data);
}
}
I am stubbing the service and returning a collection. When I run this test, media is null. Any idea, how can I set expectations on this mock ?

Just found a solution. It seems to be a little ugly, but it is the first iteration only probably more elegant version will appear soon. The idea is to create another stub and match Func<> against it:
I will provide code for my use case:
[Theory]
[InlineData(342, 31129, 3456)]
public void should_call_service_invoker_and_return_result(int number1, int number2, int expected)
{
var calculator = MockRepository.GenerateStub<ICalculator>();
calculator.Stub(_ => _.Add(number1, number2)).Return(expected);
var serviceInvoker = MockRepository.GenerateStub<ServiceInvoker<ICalculator>>();
serviceInvoker
.Stub(_ => _.Invoke(Arg<Func<ICalculator, int>>.Matches(d => d(calculator) == calculator.Add(number1, number2))))
.Return(expected);
var serviceConsumer = new ServiceConsumer(serviceInvoker);
var actual = serviceConsumer.GetAddResultFor(number1, number2);
Assert.Equal(expected, actual);
}
xUnit + extensions is used as testing framework. Please ignore Theory and InlineData stuff -- it is just another way to get rid of unnecessary test setup.
Here is the code of SUT:
public class ServiceConsumer
{
private readonly ServiceInvoker<ICalculator> serviceInvoker;
public ServiceConsumer(ServiceInvoker<ICalculator> serviceInvoker)
{
this.serviceInvoker = serviceInvoker;
}
public int GetAddResultFor(int number1, int number2)
{
return serviceInvoker.Invoke(_ => _.Add(number1, number2));
}
}
public class ServiceInvoker<T>
{
public virtual R Invoke<R>(Func<T, R> func)
{
throw new NotImplementedException();
}
}
public interface ICalculator
{
int Add(int number1, int number2);
}
Hope this will be helpful. Any suggestions of how to add more beauty are welcome :)

The lambda in your unit test compiles into a class-level method (a method inside your unit test). Inside your controller, a different lambda compiles into a class-level method (inside the controller). The stub set up in your unit test doesn't match the stub being executed in your controller, so Rhino Mocks returns a default (null). More here: http://groups.google.com/group/rhinomocks/browse_frm/thread/a33b165c16fc48ee?tvc=1