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#![warn(clippy::await_holding_refcell_ref)]
use std::cell::RefCell;
async fn bad(x: &RefCell<u32>) -> u32 {
let b = x.borrow();
baz().await
}
async fn bad_mut(x: &RefCell<u32>) -> u32 {
let b = x.borrow_mut();
baz().await
}
async fn good(x: &RefCell<u32>) -> u32 {
{
let b = x.borrow_mut();
let y = *b + 1;
}
baz().await;
let b = x.borrow_mut();
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}
async fn baz() -> u32 {
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}
async fn also_bad(x: &RefCell<u32>) -> u32 {
let first = baz().await;
let b = x.borrow_mut();
let second = baz().await;
let third = baz().await;
first + second + third
}
async fn less_bad(x: &RefCell<u32>) -> u32 {
let first = baz().await;
let b = x.borrow_mut();
let second = baz().await;
drop(b);
let third = baz().await;
first + second + third
}
async fn not_good(x: &RefCell<u32>) -> u32 {
let first = baz().await;
let second = {
let b = x.borrow_mut();
baz().await
};
let third = baz().await;
first + second + third
}
#[allow(clippy::manual_async_fn)]
fn block_bad(x: &RefCell<u32>) -> impl std::future::Future<Output = u32> + '_ {
async move {
let b = x.borrow_mut();
baz().await
}
}
fn main() {
let rc = RefCell::new(100);
good(&rc);
bad(&rc);
bad_mut(&rc);
also_bad(&rc);
less_bad(&rc);
not_good(&rc);
block_bad(&rc);
}
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