fix : Use of integer for prices, therefore also for weight

rename confusing "from" and "to" to sender_country and recipient_country as suggested

Author: SebastienCaunes

exercises/structs/structs3.rs

@@ -7,26 +7,26 @@
 
 #[derive(Debug)]
 struct Package {
-    from: String,
-    to: String,
-    weight: f32
+    sender_country: String,
+    recipient_country: String,
+    weight_in_grams: i32,
 }
 
 impl Package {
-    fn new(from: String, to: String, weight: f32) -> Package {
-        if weight <= 0.0 {
+    fn new(sender_country: String, recipient_country: String, weight_in_grams: i32) -> Package {
+        if weight_in_grams <= 0 {
             // Something goes here...
         } else {
-            return Package {from, to, weight};
+            return Package {sender_country, recipient_country, weight_in_grams};
         }
     }
 
     fn is_international(&self) -> ??? {
         // Something goes here...
     }
 
-    fn get_fees(&self, cost_per_kg: f32) -> ??? {
-        // Something goes here...
+    fn get_fees(&self, cents_per_kg: i32) -> ??? {
+        // Something goes here... (beware of grams to kg conversion)
     }
 }
 
@@ -37,31 +37,31 @@ mod tests {
     #[test]
     #[should_panic]
     fn fail_creating_weightless_package() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Austria");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Austria");
 
-        Package::new(country_from, country_to, -2.21);
+        Package::new(sender_country, recipient_country, -2210);
     }
 
     #[test]
     fn create_international_package() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Russia");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Russia");
 
-        let package = Package::new(country_from, country_to, 1.2);
+        let package = Package::new(sender_country, recipient_country, 1200);
 
         assert!(package.is_international());
     }
 
     #[test]
     fn calculate_transport_fees() {
-        let country_from = String::from("Spain");
-        let country_to = String::from("Spain");
+        let sender_country = String::from("Spain");
+        let recipient_country = String::from("Spain");
 
-        let country_fee = ???;
+        let cents_per_kg = ???;
 
-        let package = Package::new(country_from, country_to, 22.0);
+        let package = Package::new(sender_country, recipient_country, 1500);
 
-        assert_eq!(package.get_fees(country_fee), 176.0);
+        assert_eq!(package.get_fees(cents_per_kg), 4500);
     }
 }