How to rollback transactions when doing functional testing with Symfony2

Question

I'm trying to write a functional test for my project in Symfony2. I'd like to test if a user can access a page, fill up a form and submit it. I'm trying to find a way to rollback the database to the state it was before the test. I found a helper class I slightly modified at https://gist.github.com/Vp3n/5472509 which extends WebTestCase and overload setUp and tearDown methods. Here are the mods I did in order to try to make it works:

 /**
 * Before each test we start a new transaction
 * everything done in the test will be canceled ensuring isolation et speed
 */
protected function setUp()
{
    parent::setUp();
    $this->client = $this->createClient();
    $this->em = static::$kernel->getContainer()
        ->get('doctrine')
        ->getManager();
    $this->em->getConnection()->beginTransaction();
    $this->em->getConnection()->setAutoCommit(false);
}
/**
 * After each test, a rollback reset the state of 
 * the database
 */
protected function tearDown()
{
    parent::tearDown();
    if($this->em->getConnection()->isTransactionActive()){
        echo 'existing transactions';
        $this->em->getConnection()->rollback();
        $this->em->close();
    }
}

When I run the tests, it acknowledges for existing transactions but the rollback fails and modifications are persisted.

Test Logs:

Runtime:       PHP 5.6.15

.existing transactions.      2/2 (100%)existing transactions                                                                                      

Time: 5.47 seconds, Memory: 24.50MB

OK (2 tests, 5 assertions)

What am I doing wrong? Is that even the best practice?

EDIT

This worked for me:

abstract class DatabaseWebTest extends WebTestCase {
    /**
     * helper to acccess EntityManager
     */
    protected $em;
    /**
     * Helper to access test Client
     */
    protected $client;
    /**
     * Before each test we start a new transaction
     * everything done in the test will be canceled ensuring isolation et speed
     */
    protected function setUp()
    {
        parent::setUp();
        
        $this->client = $this->createClient(['environment' => 'test'], array(
            'PHP_AUTH_USER' => 'user',
            'PHP_AUTH_PW'   => 'password',
            ));
        $this->client->disableReboot();
        $this->em = $this->client->getContainer()->get('doctrine.orm.entity_manager');        
        $this->em->beginTransaction();
        $this->em->getConnection()->setAutoCommit(false);
    }
    /**
     * After each test, a rollback reset the state of 
     * the database
     */
    protected function tearDown()
    {
        parent::tearDown();

        if($this->em->getConnection()->isTransactionActive()) {
            $this->em->rollback();
        }        
    }
}

Answer 1

Are you doing more than one request with the Client? If so, you problem might be that the client shutdowns the kernel after one request was performed. But you can disable that with $this->client->disableReboot() So this snippet snippet should be idempotent:

public function setUp()
{
    $this->client = $this->createClient(['environment' => 'test']);
    $this->client->disableReboot();
    $this->em = $this->client->getContainer()->get('doctrine.orm.entity_manager');
    $this->em->beginTransaction();
}

public function tearDown()
{
    $this->em->rollback();
}

public function testCreateNewEntity()
{
    $this->client->request('GET', '/create/entity/form');
    $this->client->request('POST', '/create/entity/unique/123');
}