Only replace transformed nodes

To prevent unexpected replacements we need to just replace when something
is acually changed.

Author: jaapio

packages/guides/src/Compiler/DocumentNodeTraverser.php

@@ -55,7 +55,9 @@ private function traverseForTransformer(
 
         if ($supports) {
             $transformed = $transformer->enterNode($node, $compilerContext);
-            $shadowNode->getParent()?->replaceChild($node, $transformed);
+            if ($transformed !== $node) {
+                $shadowNode->getParent()?->replaceChild($node, $transformed);
+            }
         }
 
         foreach ($shadowNode->getChildren() as $shadowChild) {
@@ -68,7 +70,9 @@ private function traverseForTransformer(
 
         $transformed = $transformer->leaveNode($node, $compilerContext);
         if ($transformed !== null) {
-            $shadowNode->getParent()?->replaceChild($node, $transformed);
+            if ($transformed !== $node) {
+                $shadowNode->getParent()?->replaceChild($node, $transformed);
+            }
 
             return;
         }