Clean up and unify exercises

exercises/quiz1.rs

@@ -1,5 +1,3 @@
-// quiz1.rs
-//
 // This is a quiz for the following sections:
 // - Variables
 // - Functions
@@ -10,8 +8,6 @@
 // - If Mary buys more than 40 apples, each apple only costs 1 rustbuck!
 // Write a function that calculates the price of an order of apples given the
 // quantity bought.
-//
-// No hints this time ;)
 
 // Put your function here!
 // fn calculate_price_of_apples {
@@ -20,16 +16,21 @@ fn main() {
     // You can optionally experiment here.
 }
 
-// Don't modify this function!
-#[test]
-fn verify_test() {
-    let price1 = calculate_price_of_apples(35);
-    let price2 = calculate_price_of_apples(40);
-    let price3 = calculate_price_of_apples(41);
-    let price4 = calculate_price_of_apples(65);
+#[cfg(test)]
+mod tests {
+    use super::*;
 
-    assert_eq!(70, price1);
-    assert_eq!(80, price2);
-    assert_eq!(41, price3);
-    assert_eq!(65, price4);
+    // Don't modify this test!
+    #[test]
+    fn verify_test() {
+        let price1 = calculate_price_of_apples(35);
+        let price2 = calculate_price_of_apples(40);
+        let price3 = calculate_price_of_apples(41);
+        let price4 = calculate_price_of_apples(65);
+
+        assert_eq!(70, price1);
+        assert_eq!(80, price2);
+        assert_eq!(41, price3);
+        assert_eq!(65, price4);
+    }
 }