src/Controller/MainController.php

@@ -64,6 +64,7 @@ final class MainController extends AbstractController
         foreach ($finder as $file) {
             $current = &$tree;
 
+            // Dunno why it is undefined, it works
             foreach (explode('/', $file->getRelativePath()) as $part) {
                 if ($part === '') break;
 
@@ -73,9 +74,7 @@ final class MainController extends AbstractController
                 $current = &$current[$part];
             }
 
-            if (!isset($current[$part])) {
-                $current[$file->getFilenameWithoutExtension()] = [];
-            }
+            $current[$file->getFilenameWithoutExtension()] = [];
         }
 
         return $this->render('main/index.html.twig', [

templates/main/index.html.twig

@@ -11,7 +11,7 @@
             }) }}">
                 {{ name }}
             </a>
-            {{ _self.render_tree(subtree, prefix ~ name ~ '/') }}
+            {{ _self.render_tree(subtree, name ~ '/') }}
         </li>
     {% endfor %}
     </ul>