RhinoMock : Mocks Vs StrictMocks Vs DynamicMocks

Question

I understand the difference between a Mock and a Stub.

But different types of Mocks in RhinoMock framework confuses me.

Could someone explain the concepts of Mocks Vs StrictMocks Vs DynamicMocks in terms of RhinoMock framework.

your answers are greatly appreciated.

score 31 · Accepted Answer · edited Jan 15 '14 at 08:12

31

A strict mock is a mock that will throw an exception if you try to use any method that has not explicitly been set up to be used.

A dynamic (or loose) mock will not throw an exception if you try to use a method that is not set up, it will simply return ~~null~~ a default value from the method and keep going.

It is highly recommended to use dynamic mocks, as strict mocks generally turn out to be a maintenance nightmare. Here's a good blog post that has a code example of strict vs. dynamic, and why strict mocks are usually a bad idea.

edited Jan 15 '14 at 08:12

J Pollack

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answered Aug 19 '10 at 21:01

womp

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2

Nit-pick -> "return null" should be something like "returns the default value for the return type" – Merlyn Morgan-Graham Aug 19 '10 at 21:05
@Merlyn Morgan-Graham : Thanks a lot guys for the lightning fast response. much appreciated. – Eranga Dissanayaka Aug 19 '10 at 21:22
3

So what's a plain old Mock? – Matt Mar 22 '16 at 21:16

Graham · Answer 2 · 2012-10-31T09:51:18.147

-4

Strongly disagree on this point.

Arguably Test Driven Development is not possible using dynamic mocks, because what you are testing is not necessarily what you are implementing.

Imagine you added a foreach loop where you made a db call inside the loop. This scales very badly. If you used dynamic mocks to mock your dependencies, you would potentially miss mocking the db calls, hence missing the scalability issue because you wouldn't need to strictly mock every db call.

public void myMethod()
{
    externalMethod1.doSomething();
    foreach() 
    {
        externalDbCall.doSql();
    }
}

public void testMyMethodWithDynamicMocksPassesAndMissesDbCallInLoop()
{
    expect(externalMethod1.doSomething();
}

public void testMyMethodWithStrictMocksFailsAndHighlightsDbCallInLoop()
{
    expect(externalMethod1.doSomething();
}

edited Oct 31 '12 at 09:51

answered Oct 30 '12 at 11:28

Graham

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You don't seem to understand the purpose of mocks. When you mock something, you are expressly *not* testing that particular thing. If you are mocking DB code, it's because you are not testing the DB code. – Andrew Barber Oct 30 '12 at 11:34
4

Your answer would be better if you had tried to answer the question. – Gevious Oct 30 '12 at 11:50
1

@AndrewBarber I don't agree with Graham, but I think his point is that you should care *how* you call the mocked object, not what the mocks do. – Steve Greatrex Oct 30 '12 at 12:14
@SteveGreatrex I guess I can see that; it's not very clearly stated, if so. – Andrew Barber Oct 30 '12 at 12:16
@AndrewBarber agreed. I had to re-read it 3 times before replying – Steve Greatrex Oct 30 '12 at 12:17

RhinoMock : Mocks Vs StrictMocks Vs DynamicMocks

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