Merge pull request #372 from DiD92/exercise_structs3

Author: fmoko

exercises/structs/structs3.rs

@@ -0,0 +1,67 @@
+// structs3.rs
+// Structs contain more than simply some data, they can also have logic, in this
+// exercise we have defined the Package struct and we want to test some logic attached to it,
+// make the code compile and the tests pass! If you have issues execute `rustlings hint structs3`
+
+// I AM NOT DONE
+
+#[derive(Debug)]
+struct Package {
+    from: String,
+    to: String,
+    weight: f32
+}
+
+impl Package {
+    fn new(from: String, to: String, weight: f32) -> Package {
+        if weight <= 0.0 {
+            // Something goes here...
+        } else {
+            return Package {from, to, weight};
+        }
+    }
+
+    fn is_international(&self) -> ??? {
+        // Something goes here...
+    }
+
+    fn get_fees(&self, cost_per_kg: f32) -> ??? {
+        // Something goes here...
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[should_panic]
+    fn fail_creating_weightless_package() {
+        let country_from = String::from("Spain");
+        let country_to = String::from("Austria");
+
+        Package::new(country_from, country_to, -2.21);
+    }
+
+    #[test]
+    fn create_international_package() {
+        let country_from = String::from("Spain");
+        let country_to = String::from("Russia");
+        
+        let package = Package::new(country_from, country_to, 1.2);
+
+        assert!(package.is_international());
+    }
+
+    #[test]
+    fn calculate_transport_fees() {
+        let country_from = String::from("Spain");
+        let country_to = String::from("Spain");
+
+        let country_fee = ???;
+        
+        let package = Package::new(country_from, country_to, 22.0);
+        
+        assert_eq!(package.get_fees(country_fee), 176.0);
+    }
+}

info.toml

@@ -241,6 +241,19 @@ Creating instances of structs is easy, all you need to do is assign some values
 There is however some shortcuts that can be taken when instantiating structs. 
 Have a look in The Book, to find out more: https://doc.rust-lang.org/stable/book/ch05-01-defining-structs.html#creating-instances-from-other-instances-with-struct-update-syntax"""
 
+[[exercises]]
+name = "structs3"
+path = "exercises/structs/structs3.rs"
+mode = "test"
+hint = """
+The new method needs to panic if the weight is physically impossible :), how do we do that in Rust?
+
+For is_international: What makes a package international? Seems related to the places it goes through right?
+
+For calculate_transport_fees: Bigger is more expensive usually, we don't have size, but something may fit the bill here :)
+
+Have a look in The Book, to find out more about method implementations: https://doc.rust-lang.org/book/ch05-03-method-syntax.html"""
+
 # STRINGS
 
 [[exercises]]