fixed async loop

.gitignore

@@ -1 +1,2 @@
 target
+helix-term/rustfmt.toml

helix-term/src/editor.rs

@@ -1,14 +1,15 @@
-use std::io::{self, stdout, Write};
-use std::path::PathBuf;
-
 use crossterm::{
     cursor,
     cursor::position,
-    event::{self, read, Event, KeyCode, KeyEvent},
+    event::{self, read, Event, EventStream, KeyCode, KeyEvent},
     execute, queue, style,
     terminal::{self, disable_raw_mode, enable_raw_mode},
     Result,
 };
+use futures::{future::FutureExt, select, StreamExt};
+use std::io::{self, stdout, Write};
+use std::path::PathBuf;
+use std::time::Duration;
 
 const HELP: &str = r#"
  - Use q to quit
@@ -20,40 +21,40 @@ pub struct Editor {
 }
 
 impl Editor {
-    pub fn read_char() -> Result<char> {
-        loop {
-            if let Ok(Event::Key(KeyEvent {
-                code: KeyCode::Char(c),
-                ..
-            })) = event::read()
-            {
-                return Ok(c);
-            }
-        }
-    }
-
-    pub async fn print_events() -> Result<()> {
+    pub async fn print_events() {
+        let mut reader = EventStream::new();
         loop {
             // Handle key events
-            match Editor::read_char()? {
-                'h' => execute!(io::stdout(), cursor::MoveLeft(1))?,
-                'j' => execute!(io::stdout(), cursor::MoveDown(1))?,
-                'k' => execute!(io::stdout(), cursor::MoveUp(1))?,
-                'l' => execute!(io::stdout(), cursor::MoveRight(1))?,
-                'q' => {
-                    execute!(
-                        io::stdout(),
-                        style::ResetColor,
-                        cursor::Show,
-                        terminal::LeaveAlternateScreen
-                    )?;
-                    break;
+            let mut event = reader.next().await;
+            match event {
+                Some(Ok(x)) => {
+                    if let Event::Key(KeyEvent {
+                        code: KeyCode::Char(c),
+                        ..
+                    }) = x
+                    {
+                        match c {
+                            'h' => execute!(io::stdout(), cursor::MoveLeft(1)).unwrap(),
+                            'j' => execute!(io::stdout(), cursor::MoveDown(1)).unwrap(),
+                            'k' => execute!(io::stdout(), cursor::MoveUp(1)).unwrap(),
+                            'l' => execute!(io::stdout(), cursor::MoveRight(1)).unwrap(),
+                            'q' => {
+                                execute!(
+                                    io::stdout(),
+                                    style::ResetColor,
+                                    cursor::Show,
+                                    terminal::LeaveAlternateScreen
+                                );
+                                break;
+                            }
+                            _ => println!("{:?}", x),
+                        }
+                    }
                 }
-                _ => println!("use 'q' to quit."),
+                Some(Err(x)) => panic!(x),
+                None => break,
             }
         }
-
-        Ok(())
     }
 
     pub fn run() -> Result<()> {
@@ -85,6 +86,8 @@ impl Editor {
         // Send a shutdown signal.
         drop(s);
 
+        execute!(stdout, terminal::LeaveAlternateScreen)?;
+
         // Wait for threads to finish.
         for t in threads {
             t.join().unwrap();

helix-term/src/test.rs

@@ -0,0 +1,100 @@
+//! Demonstrates how to read events asynchronously with async-std.
+//!
+//! cargo run --features="event-stream" --example event-stream-async-std
+
+use std::{
+    io::{stdout, Write},
+    time::Duration,
+};
+
+use futures::{future::FutureExt, select, StreamExt};
+use smol::Timer;
+// use futures_timer::Delay;
+
+use crossterm::{
+    cursor::position,
+    event::{DisableMouseCapture, EnableMouseCapture, Event, EventStream, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode},
+    Result,
+};
+
+const HELP: &str = r#"EventStream based on futures::Stream with async-std
+ - Keyboard, mouse and terminal resize events enabled
+ - Prints "." every second if there's no event
+ - Hit "c" to print current cursor position
+ - Use Esc to quit
+"#;
+
+async fn print_events() {
+    let mut reader = EventStream::new();
+
+    loop {
+        let mut delay = Timer::after(Duration::from_millis(1_000)).fuse();
+        let mut event = reader.next().fuse();
+
+        select! {
+            _ = delay => { println!(".\r"); },
+                    maybe_event = event => {
+                          match maybe_event {
+                    Some(Ok(event)) => {
+                        println!("Event::{:?}\r", event);
+
+                        if event == Event::Key(KeyCode::Char('c').into()) {
+                            println!("Cursor position: {:?}\r", position());
+                        
+                        }
+
+                            println!("test");
+
+                        if event == Event::Key(KeyCode::Esc.into()) {
+                            break;
+                        }
+                    }
+                    Some(Err(e)) => println!("Error: {:?}\r", e),
+                    None => break,
+                }
+            }
+        };
+    }
+}
+
+fn main() -> Result<()> {
+    println!("{}", HELP);
+
+    enable_raw_mode()?;
+
+    let mut stdout = stdout();
+    execute!(stdout, EnableMouseCapture)?;
+
+    use std::thread;
+
+    // Same number of threads as there are CPU cores.
+    let num_threads = num_cpus::get().max(1);
+
+    // A channel that sends the shutdown signal.
+    let (s, r) = piper::chan::<()>(0);
+    let mut threads = Vec::new();
+
+    // Create an executor thread pool.
+    for _ in 0..num_threads {
+        // Spawn an executor thread that waits for the shutdown signal.
+        let r = r.clone();
+        threads.push(thread::spawn(move || smol::run(r.recv())));
+    }
+
+    // No need to `run()`, now we can just block on the main future.
+    smol::block_on(print_events());
+
+    // Send a shutdown signal.
+    drop(s);
+
+    // Wait for threads to finish.
+    for t in threads {
+        t.join().unwrap();
+    }
+
+    execute!(stdout, DisableMouseCapture)?;
+
+    disable_raw_mode()
+}