chore(deps): remove anyhow from dev dependencies (#1305)

Co-authored-by: Orhun Parmaksız <orhunparmaksiz@gmail.com>

Cargo.toml

@@ -45,7 +45,6 @@ unicode-truncate = "1"
 unicode-width = "0.1.13"
 
 [dev-dependencies]
-anyhow = "1.0.71"
 argh = "0.1.12"
 color-eyre = "0.6.2"
 criterion = { version = "0.5.1", features = ["html_reports"] }

examples/hello_world.rs

@@ -18,7 +18,7 @@ use std::{
     time::Duration,
 };
 
-use anyhow::{Context, Result};
+use color_eyre::{eyre::Context, Result};
 use ratatui::{
     backend::CrosstermBackend,
     crossterm::{
@@ -34,21 +34,20 @@ use ratatui::{
 /// this is not meant to be prescriptive. It is only meant to demonstrate the basic setup and
 /// teardown of a terminal application.
 ///
-/// A more robust application would probably want to handle errors and ensure that the terminal is
-/// restored to a sane state before exiting. This example does not do that. It also does not handle
-/// events or update the application state. It just draws a greeting and exits when the user
-/// presses 'q'.
+/// This example does not handle events or update the application state. It just draws a greeting
+/// and exits when the user presses 'q'.
 fn main() -> Result<()> {
-    let mut terminal = setup_terminal().context("setup failed")?;
-    run(&mut terminal).context("app loop failed")?;
-    restore_terminal(&mut terminal).context("restore terminal failed")?;
-    Ok(())
+    color_eyre::install()?; // augment errors / panics with easy to read messages
+    let mut terminal = init_terminal().context("setup failed")?;
+    let result = run(&mut terminal).context("app loop failed");
+    restore_terminal();
+    result
 }
 
 /// Setup the terminal. This is where you would enable raw mode, enter the alternate screen, and
-/// hide the cursor. This example does not handle errors. A more robust application would probably
-/// want to handle errors and ensure that the terminal is restored to a sane state before exiting.
-fn setup_terminal() -> Result<Terminal<CrosstermBackend<Stdout>>> {
+/// hide the cursor. This example does not handle errors.
+fn init_terminal() -> Result<Terminal<CrosstermBackend<Stdout>>> {
+    set_panic_hook();
     let mut stdout = io::stdout();
     enable_raw_mode().context("failed to enable raw mode")?;
     execute!(stdout, EnterAlternateScreen).context("unable to enter alternate screen")?;
@@ -57,11 +56,23 @@ fn setup_terminal() -> Result<Terminal<CrosstermBackend<Stdout>>> {
 
 /// Restore the terminal. This is where you disable raw mode, leave the alternate screen, and show
 /// the cursor.
-fn restore_terminal(terminal: &mut Terminal<CrosstermBackend<Stdout>>) -> Result<()> {
-    disable_raw_mode().context("failed to disable raw mode")?;
-    execute!(terminal.backend_mut(), LeaveAlternateScreen)
-        .context("unable to switch to main screen")?;
-    terminal.show_cursor().context("unable to show cursor")
+fn restore_terminal() {
+    // There's not a lot we can do if these fail, so we just print an error message.
+    if let Err(err) = disable_raw_mode() {
+        eprintln!("Error disabling raw mode: {err}");
+    }
+    if let Err(err) = execute!(io::stdout(), LeaveAlternateScreen) {
+        eprintln!("Error leaving alternate screen: {err}");
+    }
+}
+
+/// Replace the default panic hook with one that restores the terminal before panicking.
+fn set_panic_hook() {
+    let hook = std::panic::take_hook();
+    std::panic::set_hook(Box::new(move |panic_info| {
+        restore_terminal();
+        hook(panic_info);
+    }));
 }
 
 /// Run the application loop. This is where you would handle events and update the application
@@ -70,7 +81,7 @@ fn restore_terminal(terminal: &mut Terminal<CrosstermBackend<Stdout>>) -> Result
 /// on events, or you could have a single application state and update it based on events.
 fn run(terminal: &mut Terminal<CrosstermBackend<Stdout>>) -> Result<()> {
     loop {
-        terminal.draw(crate::render_app)?;
+        terminal.draw(render_app)?;
         if should_quit()? {
             break;
         }
@@ -88,7 +99,9 @@ fn render_app(frame: &mut Frame) {
 /// Check if the user has pressed 'q'. This is where you would handle events. This example just
 /// checks if the user has pressed 'q' and returns true if they have. It does not handle any other
 /// events. There is a 250ms timeout on the event poll so that the application can exit in a timely
-/// manner, and to ensure that the terminal is rendered at least once every 250ms.
+/// manner, and to ensure that the terminal is rendered at least once every 250ms. This allows you
+/// to do other work in the application loop, such as updating the application state, without
+/// blocking the event loop for too long.
 fn should_quit() -> Result<bool> {
     if event::poll(Duration::from_millis(250)).context("event poll failed")? {
         if let Event::Key(key) = event::read().context("event read failed")? {