feat(cli): added success-hints option for the rustlings command

closes #1373

src/verify.rs

@@ -12,6 +12,7 @@ pub fn verify<'a>(
     exercises: impl IntoIterator<Item = &'a Exercise>,
     progress: (usize, usize),
     verbose: bool,
+    success_hints: bool,
 ) -> Result<(), &'a Exercise> {
     let (num_done, total) = progress;
     let bar = ProgressBar::new(total as u64);
@@ -25,9 +26,9 @@ pub fn verify<'a>(
 
     for exercise in exercises {
         let compile_result = match exercise.mode {
-            Mode::Test => compile_and_test(exercise, RunMode::Interactive, verbose),
-            Mode::Compile => compile_and_run_interactively(exercise),
-            Mode::Clippy => compile_only(exercise),
+            Mode::Test => compile_and_test(exercise, RunMode::Interactive, verbose, success_hints),
+            Mode::Compile => compile_and_run_interactively(exercise, success_hints),
+            Mode::Clippy => compile_only(exercise, success_hints),
         };
         if !compile_result.unwrap_or(false) {
             return Err(exercise);
@@ -46,12 +47,12 @@ enum RunMode {
 
 // Compile and run the resulting test harness of the given Exercise
 pub fn test(exercise: &Exercise, verbose: bool) -> Result<(), ()> {
-    compile_and_test(exercise, RunMode::NonInteractive, verbose)?;
+    compile_and_test(exercise, RunMode::NonInteractive, verbose, false)?;
     Ok(())
 }
 
 // Invoke the rust compiler without running the resulting binary
-fn compile_only(exercise: &Exercise) -> Result<bool, ()> {
+fn compile_only(exercise: &Exercise, success_hints: bool) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Compiling {exercise}..."));
     progress_bar.enable_steady_tick(100);
@@ -59,11 +60,11 @@ fn compile_only(exercise: &Exercise) -> Result<bool, ()> {
     let _ = compile(exercise, &progress_bar)?;
     progress_bar.finish_and_clear();
 
-    Ok(prompt_for_completion(exercise, None))
+    Ok(prompt_for_completion(exercise, None, success_hints))
 }
 
 // Compile the given Exercise and run the resulting binary in an interactive mode
-fn compile_and_run_interactively(exercise: &Exercise) -> Result<bool, ()> {
+fn compile_and_run_interactively(exercise: &Exercise, success_hints: bool) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Compiling {exercise}..."));
     progress_bar.enable_steady_tick(100);
@@ -84,12 +85,12 @@ fn compile_and_run_interactively(exercise: &Exercise) -> Result<bool, ()> {
         }
     };
 
-    Ok(prompt_for_completion(exercise, Some(output.stdout)))
+    Ok(prompt_for_completion(exercise, Some(output.stdout), success_hints))
 }
 
 // Compile the given Exercise as a test harness and display
 // the output if verbose is set to true
-fn compile_and_test(exercise: &Exercise, run_mode: RunMode, verbose: bool) -> Result<bool, ()> {
+fn compile_and_test(exercise: &Exercise, run_mode: RunMode, verbose: bool, success_hints: bool) -> Result<bool, ()> {
     let progress_bar = ProgressBar::new_spinner();
     progress_bar.set_message(format!("Testing {exercise}..."));
     progress_bar.enable_steady_tick(100);
@@ -104,7 +105,7 @@ fn compile_and_test(exercise: &Exercise, run_mode: RunMode, verbose: bool) -> Re
                 println!("{}", output.stdout);
             }
             if let RunMode::Interactive = run_mode {
-                Ok(prompt_for_completion(exercise, None))
+                Ok(prompt_for_completion(exercise, None, success_hints))
             } else {
                 Ok(true)
             }
@@ -142,12 +143,11 @@ fn compile<'a, 'b>(
     }
 }
 
-fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>) -> bool {
+fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>, success_hints: bool) -> bool {
     let context = match exercise.state() {
         State::Done => return true,
         State::Pending(context) => context,
     };
-
     match exercise.mode {
         Mode::Compile => success!("Successfully ran {}!", exercise),
         Mode::Test => success!("Successfully tested {}!", exercise),
@@ -167,7 +167,6 @@ fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>) ->
         Mode::Test => "The code is compiling, and the tests pass!",
         Mode::Clippy => clippy_success_msg,
     };
-
     println!();
     if no_emoji {
         println!("~*~ {success_msg} ~*~")
@@ -183,6 +182,13 @@ fn prompt_for_completion(exercise: &Exercise, prompt_output: Option<String>) ->
         println!("{}", separator());
         println!();
     }
+    if success_hints {
+        println!("Hints:");
+        println!("{}", separator());
+        println!("{}", exercise.hint);
+        println!("{}", separator());
+        println!();
+    }
 
     println!("You can keep working on this exercise,");
     println!(