LoadMediaData.php

<?php

/**
 * ProTalk
 *
 * Copyright (c) 2012-2013, ProTalk
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Protalk\MediaBundle\Tests\Fixtures;

use Doctrine\ORM\EntityManager;
use Doctrine\Common\DataFixtures\FixtureInterface;
use Doctrine\Common\Persistence\ObjectManager;
use Doctrine\Common\Collections\ArrayCollection;
use Protalk\MediaBundle\Entity\Media;
use Protalk\MediaBundle\Entity\Mediatype;
use Protalk\MediaBundle\Entity\Speaker;
use Protalk\MediaBundle\Entity\Category;
use Protalk\MediaBundle\Entity\Tag;

class LoadMediaData implements FixtureInterface
{
    public function load(ObjectManager $manager)
    {
        $videoType = new Mediatype();
        $videoType->setName('video');
        $videoType->setType('video');

        $manager->persist($videoType);

        $speaker1 = new Speaker();
        $speaker1->setName('Joe Bloggs');

        $speaker1->setBiography('Joe Bloggs bio.');

        $manager->persist($speaker1);

        $category1 = new Category();
        $category1->setName('PHP');
        $category1->setSlug('php');

        $manager->persist($category1);

        $tag1 = new Tag();
        $tag1->setName('PHPNW');
        $tag1->setSlug('phpnw');

        $manager->persist($tag1);

        $video1 = new Media();
        $video1->setMediatype($videoType);
        $video1->setSpeakers(
            new ArrayCollection(
                array(
                    $speaker1
                )
            )
        );

        $video1->setCategories(
            new ArrayCollection(
                array(
                    $category1
                )
            )
        );

        $video1->setTags(
            new ArrayCollection(
                array(
                    $tag1
                )
            )
        );

        $video1->setDate(new \DateTime());
        $video1->setCreationDate(new \DateTime);
        $video1->setTitle('My video about PHP');
        $video1->setDescription('A video about PHP!');
        $video1->setContent('http://some.video-url.com');
        $video1->setLength('20:00:00');
        $video1->setRating(2.5);
        $video1->setVisits(100);
        $video1->setLanguage('EN');
        $video1->setSlug('php');
        $video1->setHostName('PHP');
        $video1->setHostUrl('php');
        $video1->setIsPublished(1);

        $manager->persist($video1);
        $manager->flush();
    }
}

MediaControllerTest.php

<?php

/**
 * ProTalk
 *
 * Copyright (c) 2012-2013, ProTalk
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace ProTalk\PageBundle\Tests\Controller;

use Liip\FunctionalTestBundle\Test\WebTestCase;
use Protalk\MediaBundle\Controller\MediaController;

class MediaControllerTest extends WebTestCase
{
    public function setUp()
    {
        $this->loadFixtures(
            array(
                'Protalk\MediaBundle\Tests\Fixtures\LoadMediaData'
            )
        );
    }

    public function testMediaPageShowsAllData()
    {
        $client = static::createClient();

        $client->request('GET', '/php');

        $response = $client->getResponse()->getContent();
//var_dump($response);
        $this->assertEquals(200, $client->getResponse()->getStatusCode());
    }
}

MediaRepository.php

<?php
...
    /**
     * Override native findOneBySlug method to include
     * mediatype join, reducing no. of queries to db
     * and increment no of visits made to media item
     *
     * @param  string   $slug
     * @return Doctrine Record
     */
    public function findOneBySlug($slug)
    {

        $query = $this->createQueryBuilder('c')
            ->select('m')
            ->from("ProtalkMediaBundle:Media", "m")
            ->where('m.slug = :slug')
            ->andWhere('m.isPublished = :isPublished')
            ->setParameter('slug', $slug)
            ->setParameter('isPublished', 1);

        //var_dump($query->getQuery()->getSingleScalarResult());die();
        return $query->getQuery()->getOneOrNullResult();

//        return $this->getEntityManager()
//                    ->createQuery(
//                        'SELECT m, mt
//                         FROM ProtalkMediaBundle:Media m
//                         JOIN m.mediatype mt
//                         WHERE m.slug = :slug AND m.isPublished = 1'
//                    )
//                    ->setParameter('slug', $slug)
//                    ->getSingleResult();

    }

Hi, you must change $this->createQueryBuilder('c')
By $this->_em->createQueryBuilder()

Or delete lines 15 and 16 like this:

$query = $this->createQueryBuilder('c')
        ->where('m.slug = :slug')
        ->andWhere('m.isPublished = :isPublished')
        ->setParameter('slug', $slug)
        ->setParameter('isPublished', 1);