The start of something beautiful

vendor/symfony/dependency-injection/Compiler/ResolveClassPass.php

@@ -0,0 +1,37 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Compiler;
+
+use Symfony\Component\DependencyInjection\ChildDefinition;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class ResolveClassPass implements CompilerPassInterface
+{
+    public function process(ContainerBuilder $container): void
+    {
+        foreach ($container->getDefinitions() as $id => $definition) {
+            if ($definition->isSynthetic() || null !== $definition->getClass()) {
+                continue;
+            }
+            if (preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)++$/', $id)) {
+                if ($definition instanceof ChildDefinition && !class_exists($id)) {
+                    throw new InvalidArgumentException(sprintf('Service definition "%s" has a parent but no class, and its name looks like an FQCN. Either the class is missing or you want to inherit it from the parent service. To resolve this ambiguity, please rename this service to a non-FQCN (e.g. using dots), or create the missing class.', $id));
+                }
+                $definition->setClass($id);
+            }
+        }
+    }
+}