class RepositoryControllerTest extends \Silex\WebTestCase
{

    public function testGetAllAction()
    {
        $request = $this->getMock( 'Symfony\Component\HttpFoundation\Request' );

        $app = new \ArrayAccess;
        $app['em'] = $this->getEntityManager(); // your mocked database

        $expected_results = json_encode( $you_know_this );

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

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

}