62 lines
1.3 KiB
Rust
62 lines
1.3 KiB
Rust
//@ run-pass
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//@ aux-build:arc_wake.rs
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extern crate arc_wake;
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use std::future::Future;
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use std::pin::Pin;
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use std::sync::{
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Arc,
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atomic::{self, AtomicUsize},
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};
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use std::task::{
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Context, Poll,
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};
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use arc_wake::ArcWake;
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struct Counter {
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wakes: AtomicUsize,
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}
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impl ArcWake for Counter {
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fn wake(self: Arc<Self>) {
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Self::wake_by_ref(&self)
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}
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fn wake_by_ref(arc_self: &Arc<Self>) {
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arc_self.wakes.fetch_add(1, atomic::Ordering::SeqCst);
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}
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}
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struct MyFuture;
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impl Future for MyFuture {
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type Output = ();
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fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
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// Wake twice
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let waker = cx.waker();
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waker.wake_by_ref();
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waker.wake_by_ref();
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Poll::Ready(())
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}
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}
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fn test_waker() {
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let counter = Arc::new(Counter {
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wakes: AtomicUsize::new(0),
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});
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let waker = ArcWake::into_waker(counter.clone());
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assert_eq!(2, Arc::strong_count(&counter));
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{
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let mut context = Context::from_waker(&waker);
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assert_eq!(Poll::Ready(()), Pin::new(&mut MyFuture).poll(&mut context));
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assert_eq!(2, counter.wakes.load(atomic::Ordering::SeqCst));
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}
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drop(waker);
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assert_eq!(1, Arc::strong_count(&counter));
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}
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fn main() {
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test_waker();
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}
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