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Bug recursively mocking IEnumerable<T>

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This is a migrated thread and some comments may be shown as answers.

Micah asked on 30 Jan 2014, 07:00 PM

01.using System;

02.using System.Collections.Generic;

03.using Microsoft.VisualStudio.TestTools.UnitTesting;

04.using Telerik.JustMock;

05.

06.namespace JustMockTestProject

07.{

08. public interface IFoo

09. {

10. IBar Bar { get; }

11. }

12.

13. public interface IBar : IEnumerable<Object>

14. {

15. IBaz GetBaz();

16. }

17.

18. public interface IBaz {}

19.

20. [TestClass]

21. public class JustMockTest

22. {

23. [TestMethod]

24. public void TestMethod1()

25. {

26. var foo = Mock.Create<IFoo>(Behavior.RecursiveLoose);

27. var bar = Mock.Create<IBar>(Behavior.RecursiveLoose);

28.

29. Assert.IsNotNull(bar.GetBaz()); // passes

30. Assert.IsNotNull(foo.Bar.GetBaz()); // fails

31. }

32. }

33.}

Expected Behavior: RecursiveLoose mocking behavior will cause every method to return a mocked object for reference types.
Actual Behavior: When RecursiveLoose runs into an interface that derives from IEnumerable<T>, the returned mocked object does not get recursively mocked causing NullReferenceException when a test attempts to access members on the mocked object (IBaz in the example above).

The above is a simplified test case to narrow down the source of the bug. If I have an IEnumerable<T> property on IFoo instead, then the returned object is correctly mocked (GetEnumerator doesn't return null).

As shown in the above example on line 29, mocking an IBar directly works. It is only when attempting to recursively mock an object that derives from IEnumerable that the problem occurs.

Bug recursively mocking IEnumerable<T>

3 Answers, 1 is accepted