AssetManager\Service\CollectionResolverServiceFactory::createService PHP Method

    public function createService(ServiceLocatorInterface $serviceLocator)
    {
        return $this($serviceLocator, CollectionResolver::class);
    }

 /**
  * Mainly to avoid regressions
  */
 public function testCreateServiceWithNoConfig()
 {
     $serviceManager = new ServiceManager();
     $serviceManager->setService('Config', array());
     $factory = new CollectionResolverServiceFactory();
     /* @var \AssetManager\Resolver\CollectionResolver */
     $collectionsResolver = $factory->createService($serviceManager);
     $this->assertEmpty($collectionsResolver->getCollections());
 }