ci: add job to check code format

.github/workflows/ci_format.yml

@@ -0,0 +1,24 @@
+name: Check Code Format
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+env:
+  RUST_BACKTRACE: 1
+
+jobs:
+  check:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup Rust Toolchain
+        run: |
+          rustup default nightly
+          rustup component add rustfmt
+      - name: Check Format
+        run: cargo fmt --all -- --check

compio-fs/src/file.rs

@@ -23,10 +23,12 @@ use crate::{Metadata, OpenOptions, Permissions};
 /// it was opened with. The `File` type provides **positional** read and write
 /// operations. The file does not maintain an internal cursor. The caller is
 /// required to specify an offset when issuing an operation.
-/// 
-/// 
-/// If you'd like to use methods from [`AsyncRead`](`compio_io::AsyncRead`) or [`AsyncWrite`](`compio_io::AsyncWrite`) traits,
-/// you can wrap `File` with [`std::io::Cursor`].
+///
+///
+/// If you'd like to use methods from [`AsyncRead`](`compio_io::AsyncRead`) or
+/// [`AsyncWrite`](`compio_io::AsyncWrite`) traits, you can wrap `File` with
+/// [`std::io::Cursor`].
+///
 /// # Examples
 /// ```ignore
 /// use compio::fs::File;
@@ -35,13 +37,13 @@ use crate::{Metadata, OpenOptions, Permissions};
 ///
 /// let file = File::open("foo.txt").await?;
 /// let cursor = Cursor::new(file);
-/// 
+///
 /// let int = cursor.read_u32().await?;
 /// let float = cursor.read_f32().await?;
-/// 
+///
 /// let mut string = String::new();
 /// let BufResult(result, string) = cursor.read_to_string(string).await;
-/// 
+///
 /// let mut buf = vec![0; 1024];
 /// let BufResult(result, buf) = cursor.read_exact(buf).await;
 /// ```

compio-runtime/src/runtime/scheduler/mod.rs

@@ -1,11 +1,13 @@
-use crate::runtime::scheduler::{
-    drop_hook::DropHook, local_queue::LocalQueue, send_wrapper::SendWrapper,
-};
+use std::{cell::RefCell, future::Future, marker::PhantomData, rc::Rc, sync::Arc, task::Waker};
+
 use async_task::{Runnable, Task};
 use compio_driver::NotifyHandle;
 use crossbeam_queue::SegQueue;
 use slab::Slab;
-use std::{cell::RefCell, future::Future, marker::PhantomData, rc::Rc, sync::Arc, task::Waker};
+
+use crate::runtime::scheduler::{
+    drop_hook::DropHook, local_queue::LocalQueue, send_wrapper::SendWrapper,
+};
 
 mod drop_hook;
 mod local_queue;
@@ -28,8 +30,8 @@ impl TaskQueue {
 
     /// Pushes a `Runnable` task to the appropriate queue.
     ///
-    /// If the current thread is the same as the creator thread, push to the local queue.
-    /// Otherwise, push to the sync queue.
+    /// If the current thread is the same as the creator thread, push to the
+    /// local queue. Otherwise, push to the sync queue.
     fn push(&self, runnable: Runnable, notify: &NotifyHandle) {
         if let Some(local_queue) = self.local_queue.get() {
             local_queue.push(runnable);
@@ -41,7 +43,8 @@ impl TaskQueue {
         }
     }
 
-    /// Pops at most one task from each queue and returns them as `(local_task, sync_task)`.
+    /// Pops at most one task from each queue and returns them as `(local_task,
+    /// sync_task)`.
     ///
     /// # Safety
     ///
@@ -52,7 +55,8 @@ impl TaskQueue {
 
         let local_task = local_queue.pop();
 
-        // Perform an empty check as a fast path, since `SegQueue::pop()` is more expensive.
+        // Perform an empty check as a fast path, since `SegQueue::pop()` is more
+        // expensive.
         let sync_task = if self.sync_queue.is_empty() {
             None
         } else {
@@ -145,13 +149,15 @@ impl Scheduler {
         };
 
         let schedule = {
-            // The schedule closure is managed by the `Waker` and may be dropped on another thread,
-            // so use `Weak` to ensure the `TaskQueue` is always dropped on the creator thread.
+            // The schedule closure is managed by the `Waker` and may be dropped on another
+            // thread, so use `Weak` to ensure the `TaskQueue` is always dropped
+            // on the creator thread.
             let task_queue = Arc::downgrade(&self.task_queue);
 
             move |runnable| {
-                // The `upgrade()` never fails because all tasks are dropped when the `Scheduler` is dropped,
-                // if a `Waker` is used after that, the schedule closure will never be called.
+                // The `upgrade()` never fails because all tasks are dropped when the
+                // `Scheduler` is dropped, if a `Waker` is used after that, the
+                // schedule closure will never be called.
                 task_queue.upgrade().unwrap().push(runnable, &notify);
             }
         };
@@ -216,8 +222,9 @@ impl Scheduler {
         // Then drop all scheduled tasks, which will drop all futures.
         //
         // SAFETY:
-        // Since spawned tasks are not required to be `Send`, they must always be dropped
-        // on the same thread. Because `Scheduler` is `!Send` and `!Sync`, this is safe.
+        // Since spawned tasks are not required to be `Send`, they must always be
+        // dropped on the same thread. Because `Scheduler` is `!Send` and
+        // `!Sync`, this is safe.
         //
         // This method is only called on `TaskQueue`'s creator thread
         // because `Scheduler` is `!Send` and `!Sync`.

compio-runtime/tests/drop.rs

@@ -1,4 +1,3 @@
-use futures_util::task::AtomicWaker;
 use std::{
     future::Future,
     pin::Pin,
@@ -7,6 +6,8 @@ use std::{
     thread::{self, ThreadId},
 };
 
+use futures_util::task::AtomicWaker;
+
 struct DropWatcher {
     waker: Arc<AtomicWaker>,
     thread_id: ThreadId,