public function test_accessors()
 {
     /** === Test Data === */
     $STOCK_ITEM_REF = 'stock item ref';
     $PV = 'pv';
     /** === Call and asserts  === */
     $this->obj->setStockItemRef($STOCK_ITEM_REF);
     $this->obj->setPv($PV);
     $this->assertEquals($STOCK_ITEM_REF, $this->obj->getStockItemRef());
     $this->assertEquals($PV, $this->obj->getPv());
 }