minor #18822 [Routing] Add FQCN and FQCN::method aliases when applicable (alexandre-daubois)

This PR was merged into the 6.4 branch.

Discussion
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[Routing] Add FQCN and FQCN::method aliases when applicable

Fix #18437

Commits
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e518a88 [Routing] Add FQCN and FQCN::method aliases when applicable

Author: javiereguiluz

routing.rst

@@ -2236,6 +2236,34 @@ For that reason each route has an internal name that must be unique in the
 application. If you don't set the route name explicitly with the ``name``
 option, Symfony generates an automatic name based on the controller and action.
 
+Symfony declares aliases based on the FQCN if the target class has an
+``__invoke()`` method that adds a route **and** if the target class added
+one route exactly. Symfony also automatically adds a alias for every method
+that defines only one route. This means that for the following class::
+
+        // src/Controller/MainController.php
+        namespace App\Controller;
+
+        use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+        use Symfony\Component\Routing\Annotation\Route;
+
+        final class MainController extends AbstractController
+        {
+            #[Route('/', name: 'homepage')]
+            public function homepage(): Response
+            {
+                // ...
+            }
+        }
+
+An alias named ``App\Controller\MainController::homepage`` will be declared in
+the router.
+
+.. versionadded:: 6.4
+
+    The automatic declaration of aliases based on FQCNs was introduced in
+    Symfony 6.4.
+
 Generating URLs in Controllers
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~