1 files changed, 447 insertions, 0 deletions
diff --git a/tests/sync_cancellation_token.rs b/tests/sync_cancellation_token.rs
new file mode 100644
index 0000000..279d74f
--- /dev/null
+++ b/tests/sync_cancellation_token.rs
@@ -0,0 +1,447 @@
+#![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_token_owned() {
+    let (waker, wake_counter) = new_count_waker();
+    let token = CancellationToken::new();
+    assert!(!token.is_cancelled());
+
+    let wait_fut = token.clone().cancelled_owned();
+    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.clone().cancelled_owned();
+    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_token_owned_drop_test() {
+    let (waker, wake_counter) = new_count_waker();
+    let token = CancellationToken::new();
+
+    let future = token.cancelled_owned();
+    pin!(future);
+
+    assert_eq!(
+        Poll::Pending,
+        future.as_mut().poll(&mut Context::from_waker(&waker))
+    );
+    assert_eq!(wake_counter, 0);
+
+    // let future be dropped while pinned and under pending state to
+    // find potential memory related bugs.
+}
+
+#[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);
+        }
+
+        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 great_grandchild_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!(!great_grandchild_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 great_grandchild_fut = great_grandchild_token.cancelled();
+
+    pin!(parent_fut);
+    pin!(fut);
+    pin!(sibling_fut);
+    pin!(child1_fut);
+    pin!(child2_fut);
+    pin!(grandchild_fut);
+    pin!(grandchild2_fut);
+    pin!(great_grandchild_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,
+        great_grandchild_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!(great_grandchild_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(()),
+        great_grandchild_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>>();
+}