LoadedExtension example

use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\ParameterBag\ParameterBag;
use Symfony\Component\HttpKernel\DependencyInjection\Extension;
use Symfony\Component\HttpKernel\DependencyInjection\MergeExtensionConfigurationPass;
use Symfony\Component\HttpKernel\Tests\Fixtures\AcmeFooBundle\AcmeFooBundle;

class MergeExtensionConfigurationPassTest extends TestCase
{
    public function testAutoloadMainExtension()
    {
        $container = new ContainerBuilder();
        $container->registerExtension(new LoadedExtension());
        $container->registerExtension(new NotLoadedExtension());
        $container->loadFromExtension('loaded', []);

        $configPass = new MergeExtensionConfigurationPass(['loaded', 'not_loaded']);
        $configPass->process($container);

        $this->assertTrue($container->hasDefinition('loaded.foo'));
        $this->assertTrue($container->hasDefinition('not_loaded.bar'));
    }

    public function testFooBundle()
    {