phan

Author: ridz1208

modules/media/php/mediafileprovisioner.class.inc

@@ -36,10 +36,7 @@ class MediaFileProvisioner extends \LORIS\Data\Provisioners\DBRowProvisioner
      * Cache of instrument->getFullname returned value.
      * Initializing empty keys to prevent instanciation of empty testnames.
      */
-    private $_instrumentnames = [
-        null => '',
-        ''   => ''
-    ];
+    private $_instrumentnames = [];
 
     /**
      * Create a MediaFileProvisioner, which gets files for the meida
@@ -92,7 +89,8 @@ class MediaFileProvisioner extends \LORIS\Data\Provisioners\DBRowProvisioner
         $testname = $row['testName'] ?? '';
         unset($row['testName']);
 
-        if (!isset($this->_instrumentnames[$testname])) {
+        // make sure not to call the factory when $testname is null or ''
+        if (!empty($testname) && !isset($this->_instrumentnames[$testname])) {
             $this->_instrumentnames[$testname] = \NDB_BVL_Instrument::factory(
                 $this->lorisinstance,
                 $testname,