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|
#![warn(rust_2018_idioms)]
use tokio::pin;
use tokio_util::sync::{CancellationToken, WaitForCancellationFuture};
use core::future::Future;
use core::task::{Context, Poll};
use futures_test::task::new_count_waker;
#[test]
fn cancel_token() {
let (waker, wake_counter) = new_count_waker();
let token = CancellationToken::new();
assert!(!token.is_cancelled());
let wait_fut = token.cancelled();
pin!(wait_fut);
assert_eq!(
Poll::Pending,
wait_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
let wait_fut_2 = token.cancelled();
pin!(wait_fut_2);
token.cancel();
assert_eq!(wake_counter, 1);
assert!(token.is_cancelled());
assert_eq!(
Poll::Ready(()),
wait_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
wait_fut_2.as_mut().poll(&mut Context::from_waker(&waker))
);
}
#[test]
fn cancel_child_token_through_parent() {
let (waker, wake_counter) = new_count_waker();
let token = CancellationToken::new();
let child_token = token.child_token();
assert!(!child_token.is_cancelled());
let child_fut = child_token.cancelled();
pin!(child_fut);
let parent_fut = token.cancelled();
pin!(parent_fut);
assert_eq!(
Poll::Pending,
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
token.cancel();
assert_eq!(wake_counter, 2);
assert!(token.is_cancelled());
assert!(child_token.is_cancelled());
assert_eq!(
Poll::Ready(()),
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
}
#[test]
fn cancel_grandchild_token_through_parent_if_child_was_dropped() {
let (waker, wake_counter) = new_count_waker();
let token = CancellationToken::new();
let intermediate_token = token.child_token();
let child_token = intermediate_token.child_token();
drop(intermediate_token);
assert!(!child_token.is_cancelled());
let child_fut = child_token.cancelled();
pin!(child_fut);
let parent_fut = token.cancelled();
pin!(parent_fut);
assert_eq!(
Poll::Pending,
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
token.cancel();
assert_eq!(wake_counter, 2);
assert!(token.is_cancelled());
assert!(child_token.is_cancelled());
assert_eq!(
Poll::Ready(()),
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
}
#[test]
fn cancel_child_token_without_parent() {
let (waker, wake_counter) = new_count_waker();
let token = CancellationToken::new();
let child_token_1 = token.child_token();
let child_fut = child_token_1.cancelled();
pin!(child_fut);
let parent_fut = token.cancelled();
pin!(parent_fut);
assert_eq!(
Poll::Pending,
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
child_token_1.cancel();
assert_eq!(wake_counter, 1);
assert!(!token.is_cancelled());
assert!(child_token_1.is_cancelled());
assert_eq!(
Poll::Ready(()),
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
let child_token_2 = token.child_token();
let child_fut_2 = child_token_2.cancelled();
pin!(child_fut_2);
assert_eq!(
Poll::Pending,
child_fut_2.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
token.cancel();
assert_eq!(wake_counter, 3);
assert!(token.is_cancelled());
assert!(child_token_2.is_cancelled());
assert_eq!(
Poll::Ready(()),
child_fut_2.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
}
#[test]
fn create_child_token_after_parent_was_cancelled() {
for drop_child_first in [true, false].iter().cloned() {
let (waker, wake_counter) = new_count_waker();
let token = CancellationToken::new();
token.cancel();
let child_token = token.child_token();
assert!(child_token.is_cancelled());
{
let child_fut = child_token.cancelled();
pin!(child_fut);
let parent_fut = token.cancelled();
pin!(parent_fut);
assert_eq!(
Poll::Ready(()),
child_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
drop(child_fut);
drop(parent_fut);
}
if drop_child_first {
drop(child_token);
drop(token);
} else {
drop(token);
drop(child_token);
}
}
}
#[test]
fn drop_multiple_child_tokens() {
for drop_first_child_first in &[true, false] {
let token = CancellationToken::new();
let mut child_tokens = [None, None, None];
for child in &mut child_tokens {
*child = Some(token.child_token());
}
assert!(!token.is_cancelled());
assert!(!child_tokens[0].as_ref().unwrap().is_cancelled());
for i in 0..child_tokens.len() {
if *drop_first_child_first {
child_tokens[i] = None;
} else {
child_tokens[child_tokens.len() - 1 - i] = None;
}
assert!(!token.is_cancelled());
}
drop(token);
}
}
#[test]
fn cancel_only_all_descendants() {
// ARRANGE
let (waker, wake_counter) = new_count_waker();
let parent_token = CancellationToken::new();
let token = parent_token.child_token();
let sibling_token = parent_token.child_token();
let child1_token = token.child_token();
let child2_token = token.child_token();
let grandchild_token = child1_token.child_token();
let grandchild2_token = child1_token.child_token();
let grandgrandchild_token = grandchild_token.child_token();
assert!(!parent_token.is_cancelled());
assert!(!token.is_cancelled());
assert!(!sibling_token.is_cancelled());
assert!(!child1_token.is_cancelled());
assert!(!child2_token.is_cancelled());
assert!(!grandchild_token.is_cancelled());
assert!(!grandchild2_token.is_cancelled());
assert!(!grandgrandchild_token.is_cancelled());
let parent_fut = parent_token.cancelled();
let fut = token.cancelled();
let sibling_fut = sibling_token.cancelled();
let child1_fut = child1_token.cancelled();
let child2_fut = child2_token.cancelled();
let grandchild_fut = grandchild_token.cancelled();
let grandchild2_fut = grandchild2_token.cancelled();
let grandgrandchild_fut = grandgrandchild_token.cancelled();
pin!(parent_fut);
pin!(fut);
pin!(sibling_fut);
pin!(child1_fut);
pin!(child2_fut);
pin!(grandchild_fut);
pin!(grandchild2_fut);
pin!(grandgrandchild_fut);
assert_eq!(
Poll::Pending,
parent_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
sibling_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
child1_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
child2_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
grandchild_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
grandchild2_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Pending,
grandgrandchild_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 0);
// ACT
token.cancel();
// ASSERT
assert_eq!(wake_counter, 6);
assert!(!parent_token.is_cancelled());
assert!(token.is_cancelled());
assert!(!sibling_token.is_cancelled());
assert!(child1_token.is_cancelled());
assert!(child2_token.is_cancelled());
assert!(grandchild_token.is_cancelled());
assert!(grandchild2_token.is_cancelled());
assert!(grandgrandchild_token.is_cancelled());
assert_eq!(
Poll::Ready(()),
fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
child1_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
child2_fut.as_mut().poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
grandchild_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
grandchild2_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(
Poll::Ready(()),
grandgrandchild_fut
.as_mut()
.poll(&mut Context::from_waker(&waker))
);
assert_eq!(wake_counter, 6);
}
#[test]
fn drop_parent_before_child_tokens() {
let token = CancellationToken::new();
let child1 = token.child_token();
let child2 = token.child_token();
drop(token);
assert!(!child1.is_cancelled());
drop(child1);
drop(child2);
}
#[test]
fn derives_send_sync() {
fn assert_send<T: Send>() {}
fn assert_sync<T: Sync>() {}
assert_send::<CancellationToken>();
assert_sync::<CancellationToken>();
assert_send::<WaitForCancellationFuture<'static>>();
assert_sync::<WaitForCancellationFuture<'static>>();
}
|
