diff -u b/core/modules/user/src/Tests/UserLoginTest.php b/core/modules/user/src/Tests/UserLoginTest.php
--- b/core/modules/user/src/Tests/UserLoginTest.php
+++ b/core/modules/user/src/Tests/UserLoginTest.php
@@ -178,13 +178,13 @@
       if ($flood_trigger == 'user') {
         $this->assertRaw(strtr('There have been more than @count failed login attempts for this account. It is temporarily blocked. Try again later or <a href=":url">request a new password</a>.', [
           '@count' => $this->config('user.flood')->get('user_limit'),
-          ':url' => \Drupal::url('user.pass'),
+          ':url' => \Drupal::urlGenerator()->generateFromRoute('user.pass'),
         ]));
       }
       else {
         // No uid, so the limit is IP-based.
         $this->assertRaw(strtr('Too many failed login attempts from your IP address. This IP address is temporarily blocked. Try again later or <a href=":url">request a new password</a>.', [
-          ':url' => \Drupal::url('user.pass'),
+          ':url' => \Drupal::urlGenerator()->generateFromRoute('user.pass'),
         ]));
       }
     }