php - Entity metadata wrapper -

i'm getting error metadata wrapper. have field test => entity reference multiple selection list.i following error entitymetadatawrapperexception : invalid data value given. sure matches required data type , format.

$account = entity_load_single('user', $user->uid);   $acc_wrapper = entity_metadata_wrapper('user', $account);   $list = $acc_wrapper->test->value();   $exists = false;   if (!empty($list)) {     foreach ($list $item) {       if ($item->nid == $form_state['storage']['node']->nid) {         $exists = true;         break;       }     }   }   if (!$exists) {     if (!$list) {       $list = array();       $list[] = $form_state['storage']['node']->nid;     }  $acc_wrapper->test->set($list); $acc_wrapper->save(); 

1rst quick tips

$account = entity_load_single('user', $user->uid); $acc_wrapper = entity_metadata_wrapper('user', $account); 

you don't need load entity unless need loaded after (or it's loaded). need id, , let entity_metadata_wrapper magic operate.

$acc_wrapper = entity_metadata_wrapper('user', $user->uid); 

i think error here

if (!$list) {   $list = array();   $list[] = $form_state['storage']['node']->nid; } 

$list initiated because of "$list = $acc_wrapper->test->value();", never fullfill condition, , trying set , save (because missing '}' )... makes no sense...

could try version ?

$acc_wrapper = entity_metadata_wrapper('user', $user->uid); $list = $acc_wrapper->test->value(); $exists = false;  if (!empty($list)) {   foreach ($list $item) {     if ($item->nid == $form_state['storage']['node']->nid) {       $exists = true;       break;     }   } } if (!$exists && !$list) {     $list = array($form_state['storage']['node']->nid);      $acc_wrapper->test = $list;     $acc_wrapper->save(); }