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use crate::sync::Notify;
use std::future::Future;
use std::mem::ManuallyDrop;
use std::sync::Arc;
use std::task::{Context, RawWaker, RawWakerVTable, Waker};
#[cfg(tokio_wasm_not_wasi)]
use wasm_bindgen_test::wasm_bindgen_test as test;
#[test]
fn notify_clones_waker_before_lock() {
const VTABLE: &RawWakerVTable = &RawWakerVTable::new(clone_w, wake, wake_by_ref, drop_w);
unsafe fn clone_w(data: *const ()) -> RawWaker {
let arc = ManuallyDrop::new(Arc::<Notify>::from_raw(data as *const Notify));
// Or some other arbitrary code that shouldn't be executed while the
// Notify wait list is locked.
arc.notify_one();
let _arc_clone: ManuallyDrop<_> = arc.clone();
RawWaker::new(data, VTABLE)
}
unsafe fn drop_w(data: *const ()) {
let _ = Arc::<Notify>::from_raw(data as *const Notify);
}
unsafe fn wake(_data: *const ()) {
unreachable!()
}
unsafe fn wake_by_ref(_data: *const ()) {
unreachable!()
}
let notify = Arc::new(Notify::new());
let notify2 = notify.clone();
let waker =
unsafe { Waker::from_raw(RawWaker::new(Arc::into_raw(notify2) as *const _, VTABLE)) };
let mut cx = Context::from_waker(&waker);
let future = notify.notified();
pin!(future);
// The result doesn't matter, we're just testing that we don't deadlock.
let _ = future.poll(&mut cx);
}
#[cfg(panic = "unwind")]
#[test]
fn notify_waiters_handles_panicking_waker() {
use futures::task::ArcWake;
let notify = Arc::new(Notify::new());
struct PanickingWaker(Arc<Notify>);
impl ArcWake for PanickingWaker {
fn wake_by_ref(_arc_self: &Arc<Self>) {
panic!("waker panicked");
}
}
let bad_fut = notify.notified();
pin!(bad_fut);
let waker = futures::task::waker(Arc::new(PanickingWaker(notify.clone())));
let mut cx = Context::from_waker(&waker);
let _ = bad_fut.poll(&mut cx);
let mut futs = Vec::new();
for _ in 0..32 {
let mut fut = tokio_test::task::spawn(notify.notified());
assert!(fut.poll().is_pending());
futs.push(fut);
}
assert!(std::panic::catch_unwind(|| {
notify.notify_waiters();
})
.is_err());
for mut fut in futs {
assert!(fut.poll().is_ready());
}
}
#[test]
fn notify_simple() {
let notify = Notify::new();
let mut fut1 = tokio_test::task::spawn(notify.notified());
assert!(fut1.poll().is_pending());
let mut fut2 = tokio_test::task::spawn(notify.notified());
assert!(fut2.poll().is_pending());
notify.notify_waiters();
assert!(fut1.poll().is_ready());
assert!(fut2.poll().is_ready());
}
#[test]
#[cfg(not(tokio_wasm))]
fn watch_test() {
let rt = crate::runtime::Builder::new_current_thread()
.build()
.unwrap();
rt.block_on(async {
let (tx, mut rx) = crate::sync::watch::channel(());
crate::spawn(async move {
let _ = tx.send(());
});
let _ = rx.changed().await;
});
}