Mocking Symfony2's request and session in PHPUnit

Question

I have a class that requires the Symfony2 service @request_stack which returns an instance of Symfony\Component\HttpFoundation\RequestStack. I use it to retrieve POST and GET values.

And also my class uses Symfony\Component\HttpFoundation\Session from Request->getSession() which it calls to get the current session.

Right now my class has a method that looks something like this:

class MyClass {
    public function doSomething() {
        //Get request from request stack.
        $Request = $this->RequestStack->getCurrentRequest();

        //Get a variable from request
        $var = $Request->request->get('something');
        //Processes $var into $someprocessedvar and lets say it's equal to 3.
        //Set value to session.
        $this->Request->getSession()->set('somevar', $someprocessedvar);
    }
}

I need to be able to:

1. Mock RequestStack.
2. Get Request from RequestStack
3. Get Session from Request;

With all that said how can I test that MyClass successfully set the expected value in the session?

Answer 1

Not all code is worth unit testing. Usually this is an indicator that your code could be simplified. When you unit test code that is somewhat complex the tests can become a burden and normally it would be better to do an integration of edge-to-edge test in these cases. It's also not clear in your example how your class gets the RequestStack so I will assume that it has been injected in __construct.

With that said here's how you would test that code:

protected function setUp()
{
    $this->requestStack = $this->getMock('Fully-qualified RequestStack namespace');

    $this->SUT = new MyClass($this->requestStack);
}    

/** @test */
public function it_should_store_value_in_the_session()
{
    $value = 'test value';

    $request = $this->getMock('Request');
    $request->request = $this->getMock('ParameterBag');
    $session = $this->getMock('Session');

    $this->requestStack
        ->expects($this->atLeastOnce())
        ->method('getCurrentRequest')
        ->will($this->returnValue());

    $request->request
        ->expects($this->atLeastOnce())
        ->method('get')
        ->with('something')
        ->will($this->returnValue($value));

    $request
        ->expects($this->once())
        ->method('getSession')
        ->will($this->returnValue($session));

    $session
        ->expects($this->once())
        ->method('set')
        ->with('somevar', $value);

    $this->SUT->doSomething();
}

This should give you a starting point but beware having a wall-of mocks in your tests because very small changes to the implementation details can cause your tests to fail even though the behaviour is still correct and this is something you want to avoid as much as possible so the tests aren't expensive to maintain.

Edit: I thought some more about your question and realized that typically you can inject the Session as a dependency. If that's possible in your use case it would simplify the tests a lot.

Answer 2

According to this: http://api.symfony.com/2.4/Symfony/Component/HttpFoundation/Session/Storage/MockArraySessionStorage.html

I got to work something like the following:

public function testCompanySession()
{
    $Request = new Request();
    $Request->setSession(
        new Session(new MockArraySessionStorage())
    );

    $CompanySessionMapper = new CompanyMapper($Request);

    $Company = new Company();

    $Company->setName('test');

    $CompanySessionMapper->set($Company);

    $Company = new Company();

    $CompanySessionMapper->get($Company);

    $this->assertEquals($Company->getName(), 'test');
}

Only one test per object type in my case since I'm only testing if the session name is correct and retrieving/storing the object properly in the session. CompanyMapper class uses the session to store the company object among other session/application related functions.