mock/stub Component with MXUnit

Question

I have a component called ComponentUnderTest.cfc looking as:

<cfcomponent output="false">
<cfset externalComponent = Component("Externalcomponent");

  <cffunction name="FunctionUnderTest" access="public"...>
     <cfset externalComponent.ExternalFunction()> 
  </cffunction>
</cfcomponent>

How can I mock/stub externalComponent.externFunction() in a MXUnit test componenent:

<cfcomponent displayname="ComponentTester" extends="mxunit.framework.TestCase>

 <cffunction name="MockForExternalFunction">
   .....
 </cffunction>
 ??????
 <cffunction name=TestComponent>
     <cfset componentUnderTest = CreateObject("ComponentUnderTest")>
     ?????
     <cfset componentUnderTest.FunctionUnderTest()>  <!--- should call MockForExternalFunction --->
 </cffunction>
</cfcomponent>

http://wiki.mxunit.org/display/default/Defining+a+Mock%27s+Behaviour — Henry, Oct 12 '12 at 15:48
That doesn't really help with getting the mock *into* the ComponentUnderTest instance though... — Adam Cameron, Oct 12 '12 at 21:43

score 0 · Answer 1 · answered Oct 12 '12 at 21:42

You're going to have to inject the mocked component into componentUnderTest to replace the existing on.

You can do something like this:

// I took this lot from the docs Henry pointed you to: I'm not familiar with MXUnit's mocking framework, but this sounds right
mockedObjectWithMockedMethod = mock();
mockedObjectWithMockedMethod.ExternalFunction().returns(MockForExternalFunction());

function injectVariable(name, value){
    variables[name] = value;
}
componentUnderTest.injectVariable = injectVariable;
componentUnderTest.injectVariable("externalComponent", mockedObjectWithMockedMethod);

The thing with this that MockForExternalFunction() just provided the return value to return when ExternalFunction() is called, it's not called instead of ExternalFunction(). This should be fine, though.

I'd like to check if my MockForExternalFunction is called when it is supposed to be and how many times. — Yvo Volders, Oct 15 '12 at 07:36
That is probably a separate question. I know one can do this with Mockbox, dunno about MXUnit. With MockBox, you can see how many times `externalFunction()` was called, rather than `mockForExternalFunction()`. A) it equates to the same thing, surely; B) it's the actual method you're interested in, not the mocked method. — Adam Cameron, Oct 15 '12 at 11:35

score 0 · Answer 2 · answered Aug 04 '14 at 21:41

<cfcomponent displayname="ComponentTester" extends="mxunit.framework.TestCase>

 <cffunction name="MockForExternalFunction">
   .....
 </cffunction>

 <cffunction name=TestComponent>
     <cfset componentUnderTest = CreateObject("ComponentUnderTest")>
     <cfset injectMethod(componentUnderTest, this, "MockForExternalFunction", "FunctionUnderTest") />
     <cfset componentUnderTest.FunctionUnderTest()>  <!--- should call MockForExternalFunction --->
 </cffunction>
</cfcomponent>

Inject Method

<cffunction name="injectMethod" output="false" access="public" returntype="void" hint="injects the method from giver into receiver. This is helpful for quick and dirty mocking">
    <cfargument name="Receiver" type="any" required="true" hint="the object receiving the method"/>
    <cfargument name="Giver" type="any" required="true" hint="the object giving the method"/>
    <cfargument name="FunctionName" type="string" required="true" hint="the function to be injected from the giver into the receiver"/>
    <cfargument name="FunctionNameInReceiver" type="string" required="false" default="#arguments.functionName#" hint="the function name that you will call. this is useful when you want to inject giver.someFunctionXXX but have it be called as someFunction in your receiver object">
</cffunction>

mock/stub Component with MXUnit

2 Answers2