1-function calculateTotal(items, taxRate) {
1+export function calculateTotal(items: CartItem[], taxRate: number): number {
2- var total = 0;
2+ const subtotal = items.reduce((sum, item) => sum + item.price, 0);
3- for (var i = 0; i < items.length; i++) {
3+ const tax = subtotal * (taxRate ?? 0.08);
4- total += items[i].price;
4+ return Number((subtotal + tax).toFixed(2));
6- return total + (total * taxRate);