diff --git a/tests/Issues/DowngradeNullJson/Fixture/fixture.php.inc b/tests/Issues/DowngradeNullJson/Fixture/fixture.php.inc
index 16cf462d..26757145 100644
--- a/tests/Issues/DowngradeNullJson/Fixture/fixture.php.inc
+++ b/tests/Issues/DowngradeNullJson/Fixture/fixture.php.inc
@@ -22,7 +22,7 @@ class Fixture
 {
     public function run(?int $flags = null)
     {
-        $flags = $flags ?? JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT | JSON_PRESERVE_ZERO_FRACTION | 0;
+        $flags = $flags ?? JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT | JSON_PRESERVE_ZERO_FRACTION;
 
         json_encode([], $flags);
     }