More short closures + isset instead of null checks + etc.

Author: nicolas-grekas

Controller/AbstractController.php

@@ -44,7 +44,6 @@
 use Symfony\Component\WebLink\EventListener\AddLinkHeaderListener;
 use Symfony\Component\WebLink\GenericLinkProvider;
 use Symfony\Component\WebLink\HttpHeaderSerializer;
-use Symfony\Component\WebLink\Link;
 use Symfony\Contracts\Service\Attribute\Required;
 use Symfony\Contracts\Service\ServiceSubscriberInterface;
 use Twig\Environment;
@@ -64,7 +63,7 @@ abstract class AbstractController implements ServiceSubscriberInterface
     #[Required]
     public function setContainer(ContainerInterface $container): ?ContainerInterface
     {
-        $previous = $this->container;
+        $previous = $this->container ?? null;
         $this->container = $container;
 
         return $previous;

Routing/Router.php

@@ -61,7 +61,7 @@ public function __construct(ContainerInterface $container, mixed $resource, arra
 
     public function getRouteCollection(): RouteCollection
     {
-        if (null === $this->collection) {
+        if (!isset($this->collection)) {
             $this->collection = $this->container->get('routing.loader')->load($this->resource, $this->options['resource_type']);
             $this->resolveParameters($this->collection);
             $this->collection->addResource(new ContainerParametersResource($this->collectedParameters));