diff --git a/src/Analyser/RuleErrorTransformer.php b/src/Analyser/RuleErrorTransformer.php
index ef730cac9f4..6f043096dc0 100644
--- a/src/Analyser/RuleErrorTransformer.php
+++ b/src/Analyser/RuleErrorTransformer.php
@@ -246,12 +246,14 @@ private function fix(string $fixingFile, array $fileNodes, array $fixes): ?Fixed
 			return null;
 		}
 
-		$nameResolver = new NameResolver(new Collecting(), ['replaceNodes' => false]);
-		/** @var Stmt[] $newStmts */
-		$newStmts = (new NodeTraverser(
-			$nameResolver,
-			new NewClassNamesVisitor($nameResolver->getNameContext(), $this->importNames, $this->preferSelf),
-		))->traverse($newStmts);
+		if (NewClassNamesVisitor::hasNewNames($replacingVisitor->getNewNodes())) {
+			$nameResolver = new NameResolver(new Collecting(), ['replaceNodes' => false]);
+			/** @var Stmt[] $newStmts */
+			$newStmts = (new NodeTraverser(
+				$nameResolver,
+				new NewClassNamesVisitor($nameResolver->getNameContext(), $this->importNames, $this->preferSelf),
+			))->traverse($newStmts);
+		}
 
 		$newCode = $this->getPrinter($indent)->printFormatPreserving($newStmts, $fileNodes, $parsedFile['tokens']);
 		if ($parsedFile['code'] === $newCode) {
diff --git a/src/Fixable/NewClassNamesVisitor.php b/src/Fixable/NewClassNamesVisitor.php
index e114f107c59..c27631354ce 100644
--- a/src/Fixable/NewClassNamesVisitor.php
+++ b/src/Fixable/NewClassNamesVisitor.php
@@ -95,6 +95,33 @@ public function __construct(
 		$this->phpDocParser = new PhpDocParser($config, new TypeParser($config, $constExprParser), $constExprParser);
 	}
 
+	/**
+	 * Whether there is something to write in $newNodes, the nodes returned by fixes.
+	 * The rest of the file is cloned unchanged, so the visitor would not change it.
+	 * Traversing the whole file is skipped when this returns false,
+	 * which matters in files with many fixable errors.
+	 *
+	 * @param Node[] $newNodes
+	 */
+	public static function hasNewNames(array $newNodes): bool
+	{
+		return (new NodeFinder())->findFirst($newNodes, static function (Node $node): bool {
+			if ($node instanceof FullyQualified && $node->getAttribute('origNode') === null) {
+				return true;
+			}
+
+			$doc = $node->getDocComment();
+			if ($doc === null) {
+				return false;
+			}
+
+			$originalNode = $node->getAttribute('origNode');
+			$originalDoc = $originalNode instanceof Node ? $originalNode->getDocComment() : null;
+
+			return $originalDoc === null || $originalDoc->getText() !== $doc->getText();
+		}) !== null;
+	}
+
 	#[Override]
 	public function beforeTraverse(array $nodes): ?array
 	{
diff --git a/src/Fixable/ReplacingNodeVisitor.php b/src/Fixable/ReplacingNodeVisitor.php
index 99081afc3b2..cf69a5f505e 100644
--- a/src/Fixable/ReplacingNodeVisitor.php
+++ b/src/Fixable/ReplacingNodeVisitor.php
@@ -33,6 +33,9 @@ final class ReplacingNodeVisitor extends NodeVisitorAbstract
 
 	private int $appliedCount = 0;
 
+	/** @var list<Node> */
+	private array $newNodes = [];
+
 	private bool $failed = false;
 
 	/**
@@ -115,9 +118,21 @@ public function leaveNode(Node $node): Node|int|null
 			}
 		}
 
+		$this->newNodes[] = $newNode;
+
 		return $newNode;
 	}
 
+	/**
+	 * The nodes returned by the fixes, the rest of the file is cloned unchanged.
+	 *
+	 * @return list<Node>
+	 */
+	public function getNewNodes(): array
+	{
+		return $this->newNodes;
+	}
+
 	/**
 	 * Whether every node was found and fixed.
 	 */