--TEST-- Bug #72051 (The reference in CallbackFilterIterator doesn't work as expected) --FILE-- <?php $data = [ [1,2] ]; $callbackTest = new CallbackFilterIterator(new ArrayIterator($data), function (&$current) { $current['message'] = 'Test message'; return true; }); $callbackTest->rewind(); $data = $callbackTest->current(); $callbackTest->next(); print_r($data); ?> --EXPECT-- Array ( [0] => 1 [1] => 2 [message] => Test message )