Rhino Mocks – using AssertWasCalled on Common.Logging ILog.Debug

common.loggingnetrhino-mocksspring.netunit testing

I'm having trouble using Rhino Mocks to assert that a method was called (and ideally with a particular parameter). The Method is ILog.Debug(FormatMessageHandler) in Common.Logging 2.0 using the new lamba syntax. It works fine using the old way plain ILog.Debug(string).

    // Sample Code to Test
    public int TestFuncLambda(ILog log, int a, int b)
    {
        log.Debug(m => m("TestFunc START"));

        int c = a + b;

        log.Debug(m => m("TestFunc END"));

        return c;
    }

    public int TestFunc(ILog log, int a, int b)
    {
        log.Debug("TestFunc START");

        int c = a + b;

        log.Debug("TestFunc END");

        return c;
    }

    [TestMethod]
    public void Should_log_start_TestFuncLamba()
    {
        var logger = MockRepository.GenerateMock<ILog>();

        logger.Stub(x => x.IsDebugEnabled).Return(true);

        TestFuncLambda(logger, 1, 2);

        // Doesn't work, says zero calls plus I'm not sure how to check for the word "START" in the string either
        logger.AssertWasCalled(x => x.Debug(Arg<FormatMessageHandler>.Is.Anything), o => o.IgnoreArguments());
    }

    [TestMethod]
    public void Should_log_start_TestFunc()
    {
        var logger = MockRepository.GenerateMock<ILog>();
        logger.Stub(x => x.IsDebugEnabled).Return(true);

        TestFunc(logger, 1, 2);

        // Works fine
        logger.AssertWasCalled(x => x.Debug(Arg<string>.Matches(Text.Contains("START"))));
    }

Best Answer

I'm going to assume here that you are just tinkering with Rhinomocks, and this has nothing to do with the logging framework, is that correct? I say this because there are no concrete implementations in your tests, only mocks.

Without testing your code, this line looks like it will always be zero:

logger.AssertWasCalled(x => x.Debug(Arg<FormatMessageHandler>.Is.Anything), o => o.IgnoreArguments());

because your actual method TestFunc() passes strings to log.Debug, and not a FormatMessageHandler:

So it would make sense that the number of calls is zero. Add a line to TestFunc() like this:

log.Debug(new FormatMessageHandler());

and see if that fixes it.

Related Solutions

C# – Should ‘using’ directives be inside or outside the namespace

There is actually a (subtle) difference between the two. Imagine you have the following code in File1.cs:

// File1.cs
using System;
namespace Outer.Inner
{
    class Foo
    {
        static void Bar()
        {
            double d = Math.PI;
        }
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}

Now imagine that someone adds another file (File2.cs) to the project that looks like this:

// File2.cs
namespace Outer
{
    class Math
    {
    }
}

The compiler searches Outer before looking at those using directives outside the namespace, so it finds Outer.Math instead of System.Math. Unfortunately (or perhaps fortunately?), Outer.Math has no PI member, so File1 is now broken.

This changes if you put the using inside your namespace declaration, as follows:

// File1b.cs
namespace Outer.Inner
{
    using System;
    class Foo
    {
        static void Bar()
        {
            double d = Math.PI;
        }
    }
}

Now the compiler searches System before searching Outer, finds System.Math, and all is well.

Some would argue that Math might be a bad name for a user-defined class, since there's already one in System; the point here is just that there is a difference, and it affects the maintainability of your code.

It's also interesting to note what happens if Foo is in namespace Outer, rather than Outer.Inner. In that case, adding Outer.Math in File2 breaks File1 regardless of where the using goes. This implies that the compiler searches the innermost enclosing namespace before it looks at any using directive.

What are the differences between mocks and stubs on Rhino Mocks

As per this

... Put simply there is a difference between Mock and Stub objects and RhinoMocks recognizes that allowing us to write tests that better state their purpose.

Mock objects are used to define expectations i.e: In this scenario I expect method A() to be called with such and such parameters. Mocks record and verify such expectations.

Stubs, on the other hand have a different purpose: they do not record or verify expectations, but rather allow us to “replace” the behavior, state of the “fake”object in order to utilize a test scenario ...

Best Answer

Related Solutions

C# – Should ‘using’ directives be inside or outside the namespace

What are the differences between mocks and stubs on Rhino Mocks

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