rust-clippy/tests/ui/await_holding_lock.rs
2020-10-21 11:04:26 -04:00

65 lines
1.1 KiB
Rust

// edition:2018
#![warn(clippy::await_holding_lock)]
use std::sync::Mutex;
async fn bad(x: &Mutex<u32>) -> u32 {
let guard = x.lock().unwrap();
baz().await
}
async fn good(x: &Mutex<u32>) -> u32 {
{
let guard = x.lock().unwrap();
let y = *guard + 1;
}
baz().await;
let guard = x.lock().unwrap();
47
}
async fn baz() -> u32 {
42
}
async fn also_bad(x: &Mutex<u32>) -> u32 {
let first = baz().await;
let guard = x.lock().unwrap();
let second = baz().await;
let third = baz().await;
first + second + third
}
async fn not_good(x: &Mutex<u32>) -> u32 {
let first = baz().await;
let second = {
let guard = x.lock().unwrap();
baz().await
};
let third = baz().await;
first + second + third
}
#[allow(clippy::manual_async_fn)]
fn block_bad(x: &Mutex<u32>) -> impl std::future::Future<Output = u32> + '_ {
async move {
let guard = x.lock().unwrap();
baz().await
}
}
fn main() {
let m = Mutex::new(100);
good(&m);
bad(&m);
also_bad(&m);
not_good(&m);
block_bad(&m);
}