class RepositoryControllerTest extends \PHPUnit_Framework_TestCase
{

    function tearDown()
    {
        \Mockery::close();
    }

    public function testGetAllAction()
    {

        $request = \Mockery::mock( 'Symfony\Component\HttpFoundation\Request' );

        $app = \Mockery::mock( 'Silex\Application' );

        $expected_results = [ ]; // you know this

        $db = \Mockery::mock( '\Doctrine\Common\Persistence\ObjectManager' );
        $db->shouldReceive( 'getRepository->createQueryBuilder->setFirstResult->setMaxResults->getQuery->getResult' )
            ->andReturn( $expected_results );

         // in RepositoryController use $app->offsetGet('em') instead of $app['em'];
        $app->shouldReceive( 'offsetGet' )->with( 'em' )->andReturn( $db );

        $controller = new RepositoryController( $request, $app );

        $this->assertSame( json_encode( $expected_results ), $controller->getAllAction() );
    }

}