2 files changed, 2 insertions, 2 deletions
diff --git a/Core/Authentication/Provider/UserAuthenticationProvider.php b/Core/Authentication/Provider/UserAuthenticationProvider.php
index ded53e4..2674088 100644
--- a/Core/Authentication/Provider/UserAuthenticationProvider.php
+++ b/Core/Authentication/Provider/UserAuthenticationProvider.php
@@ -62,7 +62,7 @@ abstract class UserAuthenticationProvider implements AuthenticationProviderInter
         }
 
         $username = $token->getUsername();
-        if (empty($username)) {
+        if ('' === $username || null === $username) {
             $username = 'NONE_PROVIDED';
         }
 
diff --git a/Core/Authentication/RememberMe/PersistentToken.php b/Core/Authentication/RememberMe/PersistentToken.php
index 92fcb4f..d85572d 100644
--- a/Core/Authentication/RememberMe/PersistentToken.php
+++ b/Core/Authentication/RememberMe/PersistentToken.php
@@ -40,7 +40,7 @@ final class PersistentToken implements PersistentTokenInterface
         if (empty($class)) {
             throw new \InvalidArgumentException('$class must not be empty.');
         }
-        if (empty($username)) {
+        if ('' === $username || null === $username) {
             throw new \InvalidArgumentException('$username must not be empty.');
         }
         if (empty($series)) {