WC_Order::get_billing_first_name PHP Method

    public function get_billing_first_name($context = 'view')
    {
        return $this->get_address_prop('first_name', 'billing', $context);
    }

 /**
  * Test: get_billing_first_name
  */
 function test_get_billing_first_name()
 {
     $object = new WC_Order();
     $set_to = 'Fred';
     $object->set_billing_first_name($set_to);
     $this->assertEquals($set_to, $object->get_billing_first_name());
 }