src/list.rs

@@ -13,7 +13,7 @@ use crate::{exercise::Exercise, state_file::StateFile};
 
 use self::state::{Filter, UiState};
 
-pub fn list(state_file: &mut StateFile, exercises: &'static [Exercise]) -> Result<()> {
+pub fn list(state_file: &mut StateFile, exercises: &[Exercise]) -> Result<()> {
     let mut stdout = io::stdout().lock();
     stdout.execute(EnterAlternateScreen)?;
     enable_raw_mode()?;
@@ -24,7 +24,7 @@ pub fn list(state_file: &mut StateFile, exercises: &'static [Exercise]) -> Resul
     let mut ui_state = UiState::new(state_file, exercises);
 
     'outer: loop {
-        terminal.draw(|frame| ui_state.draw(frame).unwrap())?;
+        terminal.draw(|frame| ui_state.draw(frame))?;
 
         let key = loop {
             match event::read()? {

src/list/state.rs

@@ -1,13 +1,12 @@
-use anyhow::Result;
 use ratatui::{
     layout::{Constraint, Rect},
     style::{Style, Stylize},
     text::Span,
-    widgets::{Block, Borders, HighlightSpacing, Paragraph, Row, Table, TableState},
+    widgets::{Block, Borders, HighlightSpacing, Row, Table, TableState},
     Frame,
 };
 
-use crate::{exercise::Exercise, progress_bar::progress_bar, state_file::StateFile};
+use crate::{exercise::Exercise, state_file::StateFile};
 
 #[derive(Copy, Clone, PartialEq, Eq)]
 pub enum Filter {
@@ -16,42 +15,29 @@ pub enum Filter {
     None,
 }
 
-pub struct UiState {
+pub struct UiState<'a> {
-    pub table: Table<'static>,
+    pub table: Table<'a>,
     pub message: String,
     pub filter: Filter,
-    exercises: &'static [Exercise],
+    exercises: &'a [Exercise],
-    progress: u16,
     selected: usize,
     table_state: TableState,
     last_ind: usize,
 }
 
-impl UiState {
+impl<'a> UiState<'a> {
     pub fn with_updated_rows(mut self, state_file: &StateFile) -> Self {
         let mut rows_counter: usize = 0;
-        let mut progress: u16 = 0;
         let rows = self
             .exercises
             .iter()
             .zip(state_file.progress().iter().copied())
             .enumerate()
             .filter_map(|(ind, (exercise, done))| {
-                let exercise_state = if done {
+                match (self.filter, done) {
-                    progress += 1;
+                    (Filter::Done, false) | (Filter::Pending, true) => return None,
-
+                    _ => (),
-                    if self.filter == Filter::Pending {
+                }
-                        return None;
-                    }
-
-                    "DONE".green()
-                } else {
-                    if self.filter == Filter::Done {
-                        return None;
-                    }
-
-                    "PENDING".yellow()
-                };
 
                 rows_counter += 1;
 
@@ -61,6 +47,12 @@ impl UiState {
                     Span::default()
                 };
 
+                let exercise_state = if done {
+                    "DONE".green()
+                } else {
+                    "PENDING".yellow()
+                };
+
                 Some(Row::new([
                     next,
                     exercise_state,
@@ -74,12 +66,10 @@ impl UiState {
         self.last_ind = rows_counter.saturating_sub(1);
         self.select(self.selected.min(self.last_ind));
 
-        self.progress = progress;
-
         self
     }
 
-    pub fn new(state_file: &StateFile, exercises: &'static [Exercise]) -> Self {
+    pub fn new(state_file: &StateFile, exercises: &'a [Exercise]) -> Self {
         let header = Row::new(["Next", "State", "Name", "Path"]);
 
         let max_name_len = exercises
@@ -114,7 +104,6 @@ impl UiState {
             message: String::with_capacity(128),
             filter: Filter::None,
             exercises,
-            progress: 0,
             selected,
             table_state,
             last_ind: 0,
@@ -151,7 +140,7 @@ impl UiState {
         self.select(self.last_ind);
     }
 
-    pub fn draw(&mut self, frame: &mut Frame) -> Result<()> {
+    pub fn draw(&mut self, frame: &mut Frame) {
         let area = frame.size();
 
         frame.render_stateful_widget(
@@ -160,26 +149,11 @@ impl UiState {
                 x: 0,
                 y: 0,
                 width: area.width,
-                height: area.height - 3,
+                height: area.height - 1,
             },
             &mut self.table_state,
         );
 
-        frame.render_widget(
-            Paragraph::new(Span::raw(progress_bar(
-                self.progress,
-                self.exercises.len() as u16,
-                area.width,
-            )?))
-            .block(Block::default().borders(Borders::BOTTOM)),
-            Rect {
-                x: 0,
-                y: area.height - 3,
-                width: area.width,
-                height: 2,
-            },
-        );
-
         let message = if self.message.is_empty() {
             // Help footer.
             Span::raw(
@@ -197,7 +171,5 @@ impl UiState {
                 height: 1,
             },
         );
-
-        Ok(())
     }
 }

src/main.rs

@@ -7,7 +7,6 @@ mod embedded;
 mod exercise;
 mod init;
 mod list;
-mod progress_bar;
 mod run;
 mod state_file;
 mod verify;
@@ -56,7 +55,7 @@ enum Subcommands {
     List,
 }
 
-fn find_exercise(name: &str, exercises: &'static [Exercise]) -> Result<(usize, &'static Exercise)> {
+fn find_exercise<'a>(name: &str, exercises: &'a [Exercise]) -> Result<(usize, &'a Exercise)> {
     if name == "next" {
         for (ind, exercise) in exercises.iter().enumerate() {
             if !exercise.looks_done()? {
@@ -85,13 +84,10 @@ Did you already install Rust?
 Try running `cargo --version` to diagnose the problem.",
     )?;
 
-    let mut info_file = InfoFile::parse()?;
+    let exercises = InfoFile::parse()?.exercises;
-    info_file.exercises.shrink_to_fit();
-    // Leaking is not a problem since the exercises' slice is used until the end of the program.
-    let exercises = info_file.exercises.leak();
 
     if matches!(args.command, Some(Subcommands::Init)) {
-        init::init(exercises).context("Initialization failed")?;
+        init::init(&exercises).context("Initialization failed")?;
         println!(
             "\nDone initialization!\n
 Run `cd rustlings` to go into the generated directory.
@@ -109,32 +105,32 @@ If you are just starting with Rustlings, run the command `rustlings init` to ini
         exit(1);
     }
 
-    let mut state_file = StateFile::read_or_default(exercises);
+    let mut state_file = StateFile::read_or_default(&exercises);
 
     match args.command {
         None | Some(Subcommands::Watch) => {
-            watch::watch(&state_file, exercises)?;
+            watch::watch(&state_file, &exercises)?;
         }
         // `Init` is handled above.
         Some(Subcommands::Init) => (),
         Some(Subcommands::List) => {
-            list::list(&mut state_file, exercises)?;
+            list::list(&mut state_file, &exercises)?;
         }
         Some(Subcommands::Run { name }) => {
-            let (_, exercise) = find_exercise(&name, exercises)?;
+            let (_, exercise) = find_exercise(&name, &exercises)?;
             run(exercise).unwrap_or_else(|_| exit(1));
         }
         Some(Subcommands::Reset { name }) => {
-            let (ind, exercise) = find_exercise(&name, exercises)?;
+            let (ind, exercise) = find_exercise(&name, &exercises)?;
             exercise.reset()?;
             state_file.reset(ind)?;
             println!("The exercise {exercise} has been reset!");
         }
         Some(Subcommands::Hint { name }) => {
-            let (_, exercise) = find_exercise(&name, exercises)?;
+            let (_, exercise) = find_exercise(&name, &exercises)?;
             println!("{}", exercise.hint);
         }
-        Some(Subcommands::Verify) => match verify(exercises, 0)? {
+        Some(Subcommands::Verify) => match verify(&exercises, 0)? {
             VerifyState::AllExercisesDone => println!("All exercises done!"),
             VerifyState::Failed(exercise) => bail!("Exercise {exercise} failed"),
         },

src/progress_bar.rs

@@ -1,41 +0,0 @@
-use anyhow::{bail, Result};
-use std::fmt::Write;
-
-pub fn progress_bar(progress: u16, total: u16, line_width: u16) -> Result<String> {
-    if progress > total {
-        bail!("The progress of the progress bar is higher than the maximum");
-    }
-
-    // "Progress: [".len() == 11
-    // "] xxx/xx exercises_".len() == 19 (leaving the last char empty for `total` > 99)
-    // 11 + 19 = 30
-    let wrapper_width = 30;
-
-    // If the line width is too low for a progress bar, just show the ratio.
-    if line_width < wrapper_width + 4 {
-        return Ok(format!("Progress: {progress}/{total} exercises"));
-    }
-
-    let mut line = String::with_capacity(usize::from(line_width));
-    line.push_str("Progress: [");
-
-    let remaining_width = line_width.saturating_sub(wrapper_width);
-    let filled = (remaining_width * progress) / total;
-
-    for _ in 0..filled {
-        line.push('=');
-    }
-
-    if filled < remaining_width {
-        line.push('>');
-    }
-
-    for _ in 0..(remaining_width - filled).saturating_sub(1) {
-        line.push(' ');
-    }
-
-    line.write_fmt(format_args!("] {progress:>3}/{total} exercises"))
-        .unwrap();
-
-    Ok(line)
-}

src/run.rs

@@ -1,5 +1,4 @@
 use anyhow::{bail, Result};
-use crossterm::style::Stylize;
 use std::io::{stdout, Write};
 
 use crate::exercise::Exercise;
@@ -22,7 +21,8 @@ pub fn run(exercise: &Exercise) -> Result<()> {
         bail!("Ran {exercise} with errors");
     }
 
-    println!("{}", "✓ Successfully ran {exercise}".green());
+    // TODO: Color
+    println!("Successfully ran {exercise}");
 
     Ok(())
 }

src/verify.rs

@@ -4,9 +4,9 @@ use std::io::{stdout, Write};
 
 use crate::exercise::{Exercise, Mode, State};
 
-pub enum VerifyState {
+pub enum VerifyState<'a> {
     AllExercisesDone,
-    Failed(&'static Exercise),
+    Failed(&'a Exercise),
 }
 
 // Verify that the provided container of Exercise objects
@@ -14,10 +14,7 @@ pub enum VerifyState {
 // Any such failures will be reported to the end user.
 // If the Exercise being verified is a test, the verbose boolean
 // determines whether or not the test harness outputs are displayed.
-pub fn verify(
+pub fn verify(exercises: &[Exercise], mut current_exercise_ind: usize) -> Result<VerifyState<'_>> {
-    exercises: &'static [Exercise],
-    mut current_exercise_ind: usize,
-) -> Result<VerifyState> {
     while current_exercise_ind < exercises.len() {
         let exercise = &exercises[current_exercise_ind];
 

src/watch.rs

@@ -1,13 +1,9 @@
 use anyhow::Result;
-use notify_debouncer_mini::{
+use notify_debouncer_mini::{new_debouncer, notify::RecursiveMode};
-    new_debouncer,
-    notify::{self, RecursiveMode},
-    DebounceEventResult, DebouncedEventKind,
-};
 use std::{
     io::{self, BufRead, Write},
     path::Path,
-    sync::mpsc::{channel, Sender},
+    sync::mpsc::{channel, sync_channel},
     thread,
     time::Duration,
 };
@@ -18,127 +14,63 @@ use crate::{exercise::Exercise, state_file::StateFile};
 
 use self::state::WatchState;
 
-enum InputEvent {
+enum Event {
     Hint,
     Clear,
     Quit,
-    Unrecognized,
 }
 
-enum WatchEvent {
+pub fn watch(state_file: &StateFile, exercises: &[Exercise]) -> Result<()> {
-    Input(InputEvent),
-    FileChange { exercise_ind: usize },
-    NotifyErr(notify::Error),
-    StdinErr(io::Error),
-    TerminalResize,
-}
-
-struct DebouceEventHandler {
-    tx: Sender<WatchEvent>,
-    exercises: &'static [Exercise],
-}
-
-impl notify_debouncer_mini::DebounceEventHandler for DebouceEventHandler {
-    fn handle_event(&mut self, event: DebounceEventResult) {
-        let event = match event {
-            Ok(event) => {
-                let Some(exercise_ind) = event
-                    .iter()
-                    .filter_map(|event| {
-                        if event.kind != DebouncedEventKind::Any
-                            || !event.path.extension().is_some_and(|ext| ext == "rs")
-                        {
-                            return None;
-                        }
-
-                        self.exercises
-                            .iter()
-                            .position(|exercise| event.path.ends_with(&exercise.path))
-                    })
-                    .min()
-                else {
-                    return;
-                };
-
-                WatchEvent::FileChange { exercise_ind }
-            }
-            Err(e) => WatchEvent::NotifyErr(e),
-        };
-
-        // An error occurs when the receiver is dropped.
-        // After dropping the receiver, the debouncer guard should also be dropped.
-        let _ = self.tx.send(event);
-    }
-}
-
-fn input_handler(tx: Sender<WatchEvent>) {
-    let mut stdin = io::stdin().lock();
-    let mut stdin_buf = String::with_capacity(8);
-
-    loop {
-        if let Err(e) = stdin.read_line(&mut stdin_buf) {
-            // If `send` returns an error, then the receiver is dropped and
-            // a shutdown has been already initialized.
-            let _ = tx.send(WatchEvent::StdinErr(e));
-            return;
-        }
-
-        let event = match stdin_buf.trim() {
-            "h" | "hint" => InputEvent::Hint,
-            "c" | "clear" => InputEvent::Clear,
-            "q" | "quit" => InputEvent::Quit,
-            _ => InputEvent::Unrecognized,
-        };
-
-        stdin_buf.clear();
-
-        if tx.send(WatchEvent::Input(event)).is_err() {
-            // The receiver was dropped.
-            return;
-        }
-    }
-}
-
-pub fn watch(state_file: &StateFile, exercises: &'static [Exercise]) -> Result<()> {
     let (tx, rx) = channel();
-    let mut debouncer = new_debouncer(
+    let mut debouncer = new_debouncer(Duration::from_secs(1), tx)?;
-        Duration::from_secs(1),
-        DebouceEventHandler {
-            tx: tx.clone(),
-            exercises,
-        },
-    )?;
     debouncer
         .watcher()
         .watch(Path::new("exercises"), RecursiveMode::Recursive)?;
 
-    let mut watch_state = WatchState::new(state_file, exercises);
+    let mut watch_state = WatchState::new(state_file, exercises, rx);
 
-    // TODO: bool
     watch_state.run_exercise()?;
     watch_state.render()?;
 
-    thread::spawn(move || input_handler(tx));
+    let (tx, rx) = sync_channel(0);
+    thread::spawn(move || {
+        let mut stdin = io::stdin().lock();
+        let mut stdin_buf = String::with_capacity(8);
 
-    while let Ok(event) = rx.recv() {
+        loop {
-        match event {
+            stdin.read_line(&mut stdin_buf).unwrap();
-            WatchEvent::Input(InputEvent::Hint) => {
+
-                watch_state.show_hint()?;
+            let event = match stdin_buf.trim() {
+                "h" | "hint" => Some(Event::Hint),
+                "c" | "clear" => Some(Event::Clear),
+                "q" | "quit" => Some(Event::Quit),
+                _ => None,
+            };
+
+            stdin_buf.clear();
+
+            if tx.send(event).is_err() {
+                break;
+            };
+        }
+    });
+
+    loop {
+        watch_state.try_recv_event()?;
+
+        if let Ok(event) = rx.try_recv() {
+            match event {
+                Some(Event::Hint) => {
+                    watch_state.show_hint()?;
+                }
+                Some(Event::Clear) => {
+                    watch_state.render()?;
+                }
+                Some(Event::Quit) => break,
+                None => {
+                    watch_state.handle_invalid_cmd()?;
+                }
             }
-            WatchEvent::Input(InputEvent::Clear) | WatchEvent::TerminalResize => {
-                watch_state.render()?;
-            }
-            WatchEvent::Input(InputEvent::Quit) => break,
-            WatchEvent::Input(InputEvent::Unrecognized) => {
-                watch_state.handle_invalid_cmd()?;
-            }
-            WatchEvent::FileChange { exercise_ind } => {
-                // TODO: bool
-                watch_state.run_exercise_with_ind(exercise_ind)?;
-                watch_state.render()?;
-            }
-            WatchEvent::NotifyErr(e) => return Err(e.into()),
-            WatchEvent::StdinErr(e) => return Err(e.into()),
         }
     }
 

src/watch/state.rs

@@ -1,24 +1,27 @@
-use anyhow::{Context, Result};
+use anyhow::Result;
 use crossterm::{
     style::{Attribute, ContentStyle, Stylize},
-    terminal::{size, Clear, ClearType},
+    terminal::{Clear, ClearType},
     ExecutableCommand,
 };
+use notify_debouncer_mini::{DebounceEventResult, DebouncedEventKind};
 use std::{
     fmt::Write as _,
     io::{self, StdoutLock, Write as _},
+    sync::mpsc::Receiver,
+    time::Duration,
 };
 
 use crate::{
     exercise::{Exercise, State},
-    progress_bar::progress_bar,
     state_file::StateFile,
 };
 
 pub struct WatchState<'a> {
     writer: StdoutLock<'a>,
-    exercises: &'static [Exercise],
+    rx: Receiver<DebounceEventResult>,
-    exercise: &'static Exercise,
+    exercises: &'a [Exercise],
+    exercise: &'a Exercise,
     current_exercise_ind: usize,
     stdout: Option<Vec<u8>>,
     stderr: Option<Vec<u8>>,
@@ -27,7 +30,11 @@ pub struct WatchState<'a> {
 }
 
 impl<'a> WatchState<'a> {
-    pub fn new(state_file: &StateFile, exercises: &'static [Exercise]) -> Self {
+    pub fn new(
+        state_file: &StateFile,
+        exercises: &'a [Exercise],
+        rx: Receiver<DebounceEventResult>,
+    ) -> Self {
         let current_exercise_ind = state_file.next_exercise_ind();
         let exercise = &exercises[current_exercise_ind];
 
@@ -43,6 +50,7 @@ impl<'a> WatchState<'a> {
 
         Self {
             writer,
+            rx,
             exercises,
             exercise,
             current_exercise_ind,
@@ -60,15 +68,13 @@ impl<'a> WatchState<'a> {
 
     pub fn run_exercise(&mut self) -> Result<bool> {
         let output = self.exercise.run()?;
-        self.stdout = Some(output.stdout);
 
         if !output.status.success() {
+            self.stdout = Some(output.stdout);
             self.stderr = Some(output.stderr);
             return Ok(false);
         }
 
-        self.stderr = None;
-
         if let State::Pending(context) = self.exercise.state()? {
             let mut message = format!(
                 "
@@ -100,6 +106,7 @@ You can keep working on this exercise or jump into the next one by removing the
                 )?;
             }
 
+            self.stdout = Some(output.stdout);
             self.message = Some(message);
             return Ok(false);
         }
@@ -107,14 +114,41 @@ You can keep working on this exercise or jump into the next one by removing the
         Ok(true)
     }
 
-    pub fn run_exercise_with_ind(&mut self, exercise_ind: usize) -> Result<bool> {
+    pub fn try_recv_event(&mut self) -> Result<()> {
-        self.exercise = self
+        let Ok(events) = self.rx.recv_timeout(Duration::from_millis(100)) else {
-            .exercises
+            return Ok(());
-            .get(exercise_ind)
+        };
-            .context("Invalid exercise index")?;
-        self.current_exercise_ind = exercise_ind;
 
-        self.run_exercise()
+        if let Some(current_exercise_ind) = events?
+            .iter()
+            .filter_map(|event| {
+                if event.kind != DebouncedEventKind::Any
+                    || !event.path.extension().is_some_and(|ext| ext == "rs")
+                {
+                    return None;
+                }
+
+                self.exercises
+                    .iter()
+                    .position(|exercise| event.path.ends_with(&exercise.path))
+            })
+            .min()
+        {
+            self.current_exercise_ind = current_exercise_ind;
+        } else {
+            return Ok(());
+        };
+
+        while self.current_exercise_ind < self.exercises.len() {
+            self.exercise = &self.exercises[self.current_exercise_ind];
+            if !self.run_exercise()? {
+                break;
+            }
+
+            self.current_exercise_ind += 1;
+        }
+
+        Ok(())
     }
 
     pub fn show_prompt(&mut self) -> io::Result<()> {
@@ -122,7 +156,7 @@ You can keep working on this exercise or jump into the next one by removing the
         self.writer.flush()
     }
 
-    pub fn render(&mut self) -> Result<()> {
+    pub fn render(&mut self) -> io::Result<()> {
         self.writer.execute(Clear(ClearType::All))?;
 
         if let Some(stdout) = &self.stdout {
@@ -137,18 +171,7 @@ You can keep working on this exercise or jump into the next one by removing the
             self.writer.write_all(message.as_bytes())?;
         }
 
-        self.writer.write_all(b"\n")?;
+        self.show_prompt()
-        let line_width = size()?.0;
-        let progress_bar = progress_bar(
-            self.current_exercise_ind as u16,
-            self.exercises.len() as u16,
-            line_width,
-        )?;
-        self.writer.write_all(progress_bar.as_bytes())?;
-
-        self.show_prompt()?;
-
-        Ok(())
     }
 
     pub fn show_hint(&mut self) -> io::Result<()> {