diff --git a/core/lib/Drupal/Core/Test/TestDiscovery.php b/core/lib/Drupal/Core/Test/TestDiscovery.php
index 1c319dfcab..c6e3610ca2 100644
--- a/core/lib/Drupal/Core/Test/TestDiscovery.php
+++ b/core/lib/Drupal/Core/Test/TestDiscovery.php
@@ -395,7 +395,7 @@ public static function getTestInfo($classname, $doc_comment = NULL) {
    */
   public static function parseTestClassSummary($doc_comment) {
     // Normalize line endings.
-    $doc_comment = preg_replace('/\r\n|\r/', '\n', $doc_comment);
+    $doc_comment = str_replace(['\r\n', '\r'], ['\n', '\n'], $doc_comment);
     // Strip leading and trailing doc block lines.
     $doc_comment = substr($doc_comment, 4, -4);