feat(section): hashmap + section complete w/ quiz2

exercises/quizzes/quiz2.rs

@@ -28,6 +28,25 @@ mod my_module {
 
     // TODO: Complete the function as described above.
     // pub fn transformer(input: ???) -> ??? { ??? }
+
+    pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
+        let mut output = Vec::new();
+        for (s, cmd) in input {
+            let transformed = match cmd {
+                Command::Uppercase => s.to_uppercase(),
+                Command::Trim => s.trim().to_owned(),
+                Command::Append(n) => {
+                    let mut out = s;
+                    for _ in 0..n {
+                        out.push_str("bar");
+                    }
+                    out
+                }
+            };
+            output.push(transformed)
+        }
+        output
+    }
 }
 
 fn main() {
@@ -39,6 +58,7 @@ mod tests {
     // TODO: What do we need to import to have `transformer` in scope?
     // use ???;
     use super::Command;
+    use crate::my_module::transformer;
 
     #[test]
     fn it_works() {