resolved quiz2

exercises/quizzes/quiz2.rs

@@ -28,6 +28,26 @@ mod my_module {
 
     // TODO: Complete the function as described above.
     // pub fn transformer(input: ???) -> ??? { ??? }
+    pub fn transformer(input: Vec<(String,Command)>) -> Vec<String> {
+        //Iterate the input vector to get String and Command and put in a result vector
+        input
+        .into_iter()
+        .map(|(string, command)|{ // Descructuring in string, command of each vector's entry
+            match command{
+                Command::Uppercase => string.to_uppercase(),
+                Command::Trim => string.trim().to_string(),
+                Command::Append(n) => {
+                    let mut res_string = string;
+                    for _i in 1..=n{
+                        res_string.push_str("bar")
+                    }
+                    res_string
+                }
+            }
+        })
+        .collect() // Put everything in result
+
+    }
 }
 
 fn main() {
@@ -37,7 +57,8 @@ fn main() {
 #[cfg(test)]
 mod tests {
     // TODO: What do we need to import to have `transformer` in scope?
-    // use ???;
+    // This way... is he going to search in quiz2.rs?
+    use crate::my_module::transformer;
     use super::Command;
 
     #[test]

solutions/quizzes/quiz2.rs

@@ -1,4 +1,90 @@
-fn main() {
-    // DON'T EDIT THIS SOLUTION FILE!
-    // It will be automatically filled after you finish the exercise.
+// Let's build a little machine in the form of a function. As input, we're going
+// to give a list of strings and commands. These commands determine what action
+// is going to be applied to the string. It can either be:
+// - Uppercase the string
+// - Trim the string
+// - Append "bar" to the string a specified amount of times
+//
+// The exact form of this will be:
+// - The input is going to be a vector of 2-length tuples,
+//   the first element is the string, the second one is the command.
+// - The output element is going to be a vector of strings.
+
+enum Command {
+    Uppercase,
+    Trim,
+    Append(usize),
+}
+
+mod my_module {
+    use super::Command;
+
+    // The solution with a loop. Check out `transformer_iter` for a version
+    // with iterators.
+    pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
+        let mut output = Vec::new();
+
+        for (string, command) in input {
+            // Create the new string.
+            let new_string = match command {
+                Command::Uppercase => string.to_uppercase(),
+                Command::Trim => string.trim().to_string(),
+                Command::Append(n) => string + &"bar".repeat(n),
+            };
+
+            // Push the new string to the output vector.
+            output.push(new_string);
+        }
+
+        output
+    }
+
+    // Equivalent to `transform` but uses an iterator instead of a loop for
+    // comparison. Don't worry, we will practice iterators later ;)
+    pub fn transformer_iter(input: Vec<(String, Command)>) -> Vec<String> {
+        input
+            .into_iter()
+            .map(|(string, command)| match command {
+                Command::Uppercase => string.to_uppercase(),
+                Command::Trim => string.trim().to_string(),
+                Command::Append(n) => string + &"bar".repeat(n),
+            })
+            .collect()
+    }
+}
+
+fn main() {
+    // You can optionally experiment here.
+}
+
+#[cfg(test)]
+mod tests {
+    // Import `transformer`.
+    use super::my_module::transformer;
+
+    use super::Command;
+    use super::my_module::transformer_iter;
+
+    #[test]
+    fn it_works() {
+        for transformer in [transformer, transformer_iter] {
+            let input = vec![
+                ("hello".to_string(), Command::Uppercase),
+                (" all roads lead to rome! ".to_string(), Command::Trim),
+                ("foo".to_string(), Command::Append(1)),
+                ("bar".to_string(), Command::Append(5)),
+            ];
+            let output = transformer(input);
+
+            assert_eq!(
+                output,
+                [
+                    "HELLO",
+                    "all roads lead to rome!",
+                    "foobar",
+                    "barbarbarbarbarbar",
+                ]
+            );
+        }
+    }
 }