creating_a_mock_object.md

Creating a Mock Object

In order to create a mock object you need to use any of the following methods: createMock(), createEmptyMock(), or prepareMock().

createMock()

Used to create a new mock object from scratch or from an already instantiated object.

public any createMock([string CLASSNAME], [any OBJECT], [boolean CLEARMETHODS='false'], [boolean CALLLOGGING='true'])

Parameters:

• className - The class name of the object to create and mock
• object - The instantiated object to add mocking capabilities to, similar to using prepareMock()
• clearMethods - If true, all methods in the target mock object will be removed. You can then mock only the methods that you want to mock
• callLogging - Add method call logging for all mocked methods only

collaborator = mockbox.createMock("model.myClass");

createEmptyMock()

Used to create a new mock object with all its method signatures wiped out, basically an interface with no real implementation. It will be up to you to mock all behavior.

public any createEmptyMock(string CLASSNAME, [any OBJECT], [boolean CALLLOGGING='true'])

Parameters:

• className - The class name of the object to create and mock
• object - The instantiated object to add mocking capabilities to, similar to using prepareMock()
• callLogging - Add method call logging for all mocked methods only

user = mockbox.createEmptyMock("model.User");

prepareMock()

Decorate an already instantiated object with mocking capabilities. It does not wipe out the object's methods or signature, it only decorates it (mixes-in methods) with methods for mocking operations. This is great for doing targeted mocking for specific methods, private methods, properties and more.

public any prepareMock([any OBJECT], [boolean CALLLOGGING='true'])

Parameters:

• object - The already instantiated object to prepare for mocking
• callLogging - Add method call logging for all mocked methods only

myService = createObject("component","model.services.MyCoolService").init();
// prepare it for mocking
mockBox.prepareMock( myService );

Caution If call logging is turned on, then the mock object will keep track of all method calls to mocked methods ONLY. It will store them in a sequential array with all the arguments the method was called with (named or ordered). This is essential if you need to investigate if a method was called and with what arguments. You can also use this to inspect save or update calls based on mocked external repositories.

**Sample:**

Let's say that we have a user service layer object that relies on the following objects:

• sessionstorage - a session facade object
• transfer - the transfer ORM
• userDAO - a data access object for complex query operations

We can start testing our user service and mocking its dependencies by preparing it in a test case CFC with the following setup() method:

component extends=”testbox.system.BaseSpec” {

	function beforeAll(){
		//Create the User Service to test, do not remove methods, just prepare for mocking.
		userService = createMock("model.UserService");

		// Mock the session facade, I am using the coldbox one, it can be any facade though
		mockSession= createEmptyMock(className='coldbox.system.plugins.SessionStorage');

		// Mock Transfer
		mockTransfer = createEmptyMock(className='transfer.com.Transfer');

		// Mock DAO
		mockDAO = createEmptyMock(className='model.UserDAO');

		//Init the User Service	with mock dependencies
		userService.init(mockTransfer,mockSession,mockDAO);
	}

	function run(){

		describe( "User Service", function(){
			it( "can get data", function(){
				// mock a query using mockbox's querysimulator
				mockQuery = querySim("id, name
				1|Luis Majano
				2|Alexia Majano");
				// mock the DAO call with this mocked query as its return
				mockDAO.$("getData", mockQuery);

				data = userService.getData();
				expect( data ).toBe( mockQuery );
			});
		});

	}

}

The service CFC we just injected mocked dependencies:

<cfcomponent name="UserService" output="False">

<cffunction name="init" returntype="UserService" output="False">
  <cfargument name="transfer">
  <cfargument name="sessionStorage">
  <cfargument name="userDAO">
  <cfscript>
    instance.transfer = arguments.transfer;
    instance.sessionStorage = arguments.sessionStorage;
    instance.userDAO = arguments.userDAO;

    return this;
  </cfscript>
</cffunction>

<cffunction name="getData" returntype="query" output="false">
	<cfreturn instance.userDao.getData()>
</cffunction>

</cfcomponent>