FPPP: Fall back if comment in list node changes (#420)

lib/PhpParser/PrettyPrinterAbstract.php

@@ -663,6 +663,12 @@ abstract class PrettyPrinterAbstract
                 return null;
             }
 
+            if ($arrItem->getComments() !== $origArrItem->getComments()) {
+                // Comments changed, fall back
+                // TODO This should only reprint the changed comments
+                return null;
+            }
+
             $itemStartPos = $origArrItem->getStartTokenPos();
             $itemEndPos = $origArrItem->getEndTokenPos();
             if ($itemStartPos < 0 || $itemEndPos < 0) {

test/code/formatPreservation/commentsFallback.test

@@ -0,0 +1,11 @@
+Fallback on comment change (for now at least)
+-----
+<?php
+// Test
+foo();
+-----
+$stmts[0]->setAttribute('comments', []);
+-----
+<?php
+
+foo();