Question

An AI wrote this Swift code to parse a price from an API response and format it for display in a checkout cell. It passes the dev's manual test, but you get a spike of crash reports in production from a single screen. What's the bug and how would you catch it before shipping?

1func displayPrice(from json: [String: Any]) -> String {2    let cents = json["amount_cents"] as! Int3    let currency = json["currency"]! as! String4    let dollars = Double(cents) / 100.05    return formatter.string(currency: currency, amount: dollars)!6}