Separate WatchState

src/watch.rs

@@ -1,25 +1,18 @@
 use anyhow::Result;
-use crossterm::{
+use notify_debouncer_mini::{new_debouncer, notify::RecursiveMode};
-    style::{Attribute, ContentStyle, Stylize},
-    terminal::{Clear, ClearType},
-    ExecutableCommand,
-};
-use notify_debouncer_mini::{
-    new_debouncer, notify::RecursiveMode, DebounceEventResult, DebouncedEventKind,
-};
 use std::{
-    fmt::Write as _,
+    io::{self, BufRead, Write},
-    io::{self, BufRead, StdoutLock, Write},
     path::Path,
-    sync::mpsc::{channel, sync_channel, Receiver},
+    sync::mpsc::{channel, sync_channel},
     thread,
     time::Duration,
 };
 
-use crate::{
+mod state;
-    exercise::{self, Exercise},
+
-    state_file::StateFile,
+use crate::{exercise::Exercise, state_file::StateFile};
-};
+
+use self::state::WatchState;
 
 enum Event {
     Hint,
@@ -27,130 +20,6 @@ enum Event {
     Quit,
 }
 
-struct WatchState<'a> {
-    writer: StdoutLock<'a>,
-    rx: Receiver<DebounceEventResult>,
-    exercises: &'a [Exercise],
-    exercise: &'a Exercise,
-    current_exercise_ind: usize,
-    stdout: Option<Vec<u8>>,
-    stderr: Option<Vec<u8>>,
-    message: Option<String>,
-    prompt: Vec<u8>,
-}
-
-impl<'a> WatchState<'a> {
-    fn run_exercise(&mut self) -> Result<bool> {
-        let output = self.exercise.run()?;
-
-        if !output.status.success() {
-            self.stdout = Some(output.stdout);
-            self.stderr = Some(output.stderr);
-            return Ok(false);
-        }
-
-        if let exercise::State::Pending(context) = self.exercise.state()? {
-            let mut message = format!(
-                "
-You can keep working on this exercise or jump into the next one by removing the {} comment:
-
-",
-                "`I AM NOT DONE`".bold(),
-            );
-
-            for context_line in context {
-                let formatted_line = if context_line.important {
-                    context_line.line.bold()
-                } else {
-                    context_line.line.stylize()
-                };
-
-                writeln!(
-                    message,
-                    "{:>2} {}  {}",
-                    ContentStyle {
-                        foreground_color: Some(crossterm::style::Color::Blue),
-                        background_color: None,
-                        underline_color: None,
-                        attributes: Attribute::Bold.into()
-                    }
-                    .apply(context_line.number),
-                    "|".blue(),
-                    formatted_line,
-                )?;
-            }
-
-            self.stdout = Some(output.stdout);
-            self.message = Some(message);
-            return Ok(false);
-        }
-
-        Ok(true)
-    }
-
-    fn try_recv_event(&mut self) -> Result<()> {
-        let Ok(events) = self.rx.recv_timeout(Duration::from_millis(100)) else {
-            return Ok(());
-        };
-
-        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(())
-    }
-
-    fn prompt(&mut self) -> io::Result<()> {
-        self.writer.write_all(&self.prompt)?;
-        self.writer.flush()
-    }
-
-    fn render(&mut self) -> Result<()> {
-        self.writer.execute(Clear(ClearType::All))?;
-
-        if let Some(stdout) = &self.stdout {
-            self.writer.write_all(stdout)?;
-        }
-
-        if let Some(stderr) = &self.stderr {
-            self.writer.write_all(stderr)?;
-        }
-
-        if let Some(message) = &self.message {
-            self.writer.write_all(message.as_bytes())?;
-        }
-
-        self.prompt()?;
-
-        Ok(())
-    }
-}
-
 pub fn watch(state_file: &StateFile, exercises: &[Exercise]) -> Result<()> {
     let (tx, rx) = channel();
     let mut debouncer = new_debouncer(Duration::from_secs(1), tx)?;
@@ -158,29 +27,7 @@ pub fn watch(state_file: &StateFile, exercises: &[Exercise]) -> Result<()> {
         .watcher()
         .watch(Path::new("exercises"), RecursiveMode::Recursive)?;
 
-    let current_exercise_ind = state_file.next_exercise_ind();
+    let mut watch_state = WatchState::new(state_file, exercises, rx);
-
-    let exercise = &exercises[current_exercise_ind];
-
-    let writer = io::stdout().lock();
-
-    let mut watch_state = WatchState {
-        writer,
-        rx,
-        exercises,
-        exercise,
-        current_exercise_ind,
-        stdout: None,
-        stderr: None,
-        message: None,
-        prompt: format!(
-            "\n\n{}int/{}lear/{}uit? ",
-            "h".bold(),
-            "c".bold(),
-            "q".bold()
-        )
-        .into_bytes(),
-    };
 
     watch_state.run_exercise()?;
     watch_state.render()?;
@@ -214,24 +61,20 @@ pub fn watch(state_file: &StateFile, exercises: &[Exercise]) -> Result<()> {
         if let Ok(event) = rx.try_recv() {
             match event {
                 Some(Event::Hint) => {
-                    watch_state
+                    watch_state.show_hint()?;
-                        .writer
-                        .write_all(watch_state.exercise.hint.as_bytes())?;
-                    watch_state.prompt()?;
                 }
                 Some(Event::Clear) => {
                     watch_state.render()?;
                 }
                 Some(Event::Quit) => break,
                 None => {
-                    watch_state.writer.write_all(b"Invalid command")?;
+                    watch_state.handle_invalid_cmd()?;
-                    watch_state.prompt()?;
                 }
             }
         }
     }
 
-    watch_state.writer.write_all(b"
+    watch_state.into_writer().write_all(b"
 We hope you're enjoying learning Rust!
 If you want to continue working on the exercises at a later point, you can simply run `rustlings` again.
 ")?;

src/watch/state.rs

@@ -0,0 +1,186 @@
+use anyhow::Result;
+use crossterm::{
+    style::{Attribute, ContentStyle, Stylize},
+    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},
+    state_file::StateFile,
+};
+
+pub struct WatchState<'a> {
+    writer: StdoutLock<'a>,
+    rx: Receiver<DebounceEventResult>,
+    exercises: &'a [Exercise],
+    exercise: &'a Exercise,
+    current_exercise_ind: usize,
+    stdout: Option<Vec<u8>>,
+    stderr: Option<Vec<u8>>,
+    message: Option<String>,
+    prompt: Vec<u8>,
+}
+
+impl<'a> WatchState<'a> {
+    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];
+
+        let writer = io::stdout().lock();
+
+        let prompt = format!(
+            "\n\n{}int/{}lear/{}uit? ",
+            "h".bold(),
+            "c".bold(),
+            "q".bold()
+        )
+        .into_bytes();
+
+        Self {
+            writer,
+            rx,
+            exercises,
+            exercise,
+            current_exercise_ind,
+            stdout: None,
+            stderr: None,
+            message: None,
+            prompt,
+        }
+    }
+
+    #[inline]
+    pub fn into_writer(self) -> StdoutLock<'a> {
+        self.writer
+    }
+
+    pub fn run_exercise(&mut self) -> Result<bool> {
+        let output = self.exercise.run()?;
+
+        if !output.status.success() {
+            self.stdout = Some(output.stdout);
+            self.stderr = Some(output.stderr);
+            return Ok(false);
+        }
+
+        if let State::Pending(context) = self.exercise.state()? {
+            let mut message = format!(
+                "
+You can keep working on this exercise or jump into the next one by removing the {} comment:
+
+",
+                "`I AM NOT DONE`".bold(),
+            );
+
+            for context_line in context {
+                let formatted_line = if context_line.important {
+                    context_line.line.bold()
+                } else {
+                    context_line.line.stylize()
+                };
+
+                writeln!(
+                    message,
+                    "{:>2} {}  {}",
+                    ContentStyle {
+                        foreground_color: Some(crossterm::style::Color::Blue),
+                        background_color: None,
+                        underline_color: None,
+                        attributes: Attribute::Bold.into()
+                    }
+                    .apply(context_line.number),
+                    "|".blue(),
+                    formatted_line,
+                )?;
+            }
+
+            self.stdout = Some(output.stdout);
+            self.message = Some(message);
+            return Ok(false);
+        }
+
+        Ok(true)
+    }
+
+    pub fn try_recv_event(&mut self) -> Result<()> {
+        let Ok(events) = self.rx.recv_timeout(Duration::from_millis(100)) else {
+            return Ok(());
+        };
+
+        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<()> {
+        self.writer.write_all(&self.prompt)?;
+        self.writer.flush()
+    }
+
+    pub fn render(&mut self) -> io::Result<()> {
+        self.writer.execute(Clear(ClearType::All))?;
+
+        if let Some(stdout) = &self.stdout {
+            self.writer.write_all(stdout)?;
+        }
+
+        if let Some(stderr) = &self.stderr {
+            self.writer.write_all(stderr)?;
+        }
+
+        if let Some(message) = &self.message {
+            self.writer.write_all(message.as_bytes())?;
+        }
+
+        self.show_prompt()
+    }
+
+    pub fn show_hint(&mut self) -> io::Result<()> {
+        self.writer.write_all(self.exercise.hint.as_bytes())?;
+        self.show_prompt()
+    }
+
+    pub fn handle_invalid_cmd(&mut self) -> io::Result<()> {
+        self.writer.write_all(b"Invalid command")?;
+        self.show_prompt()
+    }
+}