chay.dev
1#[derive(Debug)]
2struct Package {
3 sender_country: String,
4 recipient_country: String,
5 weight_in_grams: u32,
6}
7
8impl Package {
9 fn new(sender_country: String, recipient_country: String, weight_in_grams: u32) -> Self {
10 if weight_in_grams < 10 {
11 // This isn't how you should handle errors in Rust, but we will
12 // learn about error handling later.
13 panic!("Can't ship a package with weight below 10 grams");
14 }
15
16 Self {
17 sender_country,
18 recipient_country,
19 weight_in_grams,
20 }
21 }
22
23 fn is_international(&self) -> bool {
24 // ^^^^^^^ added
25 self.sender_country != self.recipient_country
26 }
27
28 fn get_fees(&self, cents_per_gram: u32) -> u32 {
29 // ^^^^^^ added
30 self.weight_in_grams * cents_per_gram
31 }
32}
33
34fn main() {
35 // You can optionally experiment here.
36}
37
38#[cfg(test)]
39mod tests {
40 use super::*;
41
42 #[test]
43 #[should_panic]
44 fn fail_creating_weightless_package() {
45 let sender_country = String::from("Spain");
46 let recipient_country = String::from("Austria");
47
48 Package::new(sender_country, recipient_country, 5);
49 }
50
51 #[test]
52 fn create_international_package() {
53 let sender_country = String::from("Spain");
54 let recipient_country = String::from("Russia");
55
56 let package = Package::new(sender_country, recipient_country, 1200);
57
58 assert!(package.is_international());
59 }
60
61 #[test]
62 fn create_local_package() {
63 let sender_country = String::from("Canada");
64 let recipient_country = sender_country.clone();
65
66 let package = Package::new(sender_country, recipient_country, 1200);
67
68 assert!(!package.is_international());
69 }
70
71 #[test]
72 fn calculate_transport_fees() {
73 let sender_country = String::from("Spain");
74 let recipient_country = String::from("Spain");
75
76 let cents_per_gram = 3;
77
78 let package = Package::new(sender_country, recipient_country, 1500);
79
80 assert_eq!(package.get_fees(cents_per_gram), 4500);
81 assert_eq!(package.get_fees(cents_per_gram * 2), 9000);
82 }
83}