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86 lines
1.4 KiB
Rust
86 lines
1.4 KiB
Rust
#![warn(clippy::await_holding_refcell_ref)]
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use std::cell::RefCell;
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async fn bad(x: &RefCell<u32>) -> u32 {
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let b = x.borrow();
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baz().await
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}
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async fn bad_mut(x: &RefCell<u32>) -> u32 {
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let b = x.borrow_mut();
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baz().await
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}
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async fn good(x: &RefCell<u32>) -> u32 {
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{
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let b = x.borrow_mut();
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let y = *b + 1;
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}
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baz().await;
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let b = x.borrow_mut();
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47
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}
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async fn baz() -> u32 {
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42
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}
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async fn also_bad(x: &RefCell<u32>) -> u32 {
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let first = baz().await;
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let b = x.borrow_mut();
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let second = baz().await;
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let third = baz().await;
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first + second + third
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}
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async fn less_bad(x: &RefCell<u32>) -> u32 {
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let first = baz().await;
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let b = x.borrow_mut();
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let second = baz().await;
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drop(b);
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let third = baz().await;
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first + second + third
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}
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async fn not_good(x: &RefCell<u32>) -> u32 {
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let first = baz().await;
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let second = {
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let b = x.borrow_mut();
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baz().await
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};
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let third = baz().await;
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first + second + third
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}
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#[allow(clippy::manual_async_fn)]
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fn block_bad(x: &RefCell<u32>) -> impl std::future::Future<Output = u32> + '_ {
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async move {
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let b = x.borrow_mut();
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baz().await
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}
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}
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fn main() {
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let rc = RefCell::new(100);
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good(&rc);
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bad(&rc);
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bad_mut(&rc);
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also_bad(&rc);
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less_bad(&rc);
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not_good(&rc);
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block_bad(&rc);
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}
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