[Renaming] Throw on same old and new class in RenameClassRector configuration (#8515)

Author: TomasVotruba

rules/Renaming/Rector/Name/RenameClassRector.php

@@ -15,6 +15,7 @@
 use PHPStan\Reflection\ReflectionProvider;
 use Rector\Configuration\RenamedClassesDataCollector;
 use Rector\Contract\Rector\ConfigurableRectorInterface;
+use Rector\Exception\Configuration\InvalidConfigurationException;
 use Rector\NodeTypeResolver\Node\AttributeKey;
 use Rector\Rector\AbstractRector;
 use Rector\Renaming\NodeManipulator\ClassRenamer;
@@ -119,6 +120,15 @@ public function configure(array $configuration): void
         Assert::allString($configuration);
         Assert::allString(array_keys($configuration));
 
+        foreach ($configuration as $oldClass => $newClass) {
+            if ($oldClass === $newClass) {
+                throw new InvalidConfigurationException(sprintf(
+                    'Rename "%s" class to a different one, as the old and new class name are the same',
+                    $oldClass
+                ));
+            }
+        }
+
         $this->renamedClassesDataCollector->addOldToNewClasses($configuration);
     }
 

tests/Renaming/Rector/Name/RenameClassRector/SameOldToNewClassTest.php

@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Tests\Renaming\Rector\Name\RenameClassRector;
+
+use Rector\Exception\Configuration\InvalidConfigurationException;
+use Rector\Renaming\Rector\Name\RenameClassRector;
+use Rector\Testing\PHPUnit\AbstractLazyTestCase;
+
+final class SameOldToNewClassTest extends AbstractLazyTestCase
+{
+    public function test(): void
+    {
+        $renameClassRector = $this->make(RenameClassRector::class);
+
+        $this->expectException(InvalidConfigurationException::class);
+
+        $renameClassRector->configure([
+            'App\SomeClass' => 'App\SomeClass',
+        ]);
+    }
+}