WC_Order::set_date_paid PHP Метод

    public function set_date_paid($timestamp)
    {
        $this->set_prop('date_paid', is_numeric($timestamp) ? $timestamp : strtotime($timestamp));
    }

 /**
  * Test: get_date_paid
  */
 function test_get_date_paid()
 {
     $object = new WC_Order();
     $set_to = 'PayPal';
     $object->set_date_paid('2016-12-12');
     $this->assertEquals(1481500800, $object->get_date_paid());
     $object->set_date_paid('1481500800');
     $this->assertEquals(1481500800, $object->get_date_paid());
 }