1 files changed, 234 insertions, 0 deletions
diff --git a/third_party/rust/tokio/tests/sync_oneshot.rs b/third_party/rust/tokio/tests/sync_oneshot.rs
new file mode 100644
index 0000000000..13e526d48e
--- /dev/null
+++ b/third_party/rust/tokio/tests/sync_oneshot.rs
@@ -0,0 +1,234 @@
+#![warn(rust_2018_idioms)]
+#![cfg(feature = "full")]
+
+use tokio::sync::oneshot;
+use tokio_test::*;
+
+use std::future::Future;
+use std::pin::Pin;
+
+trait AssertSend: Send {}
+impl AssertSend for oneshot::Sender<i32> {}
+impl AssertSend for oneshot::Receiver<i32> {}
+
+#[test]
+fn send_recv() {
+    let (tx, rx) = oneshot::channel();
+    let mut rx = task::spawn(rx);
+
+    assert_pending!(rx.poll());
+
+    assert_ok!(tx.send(1));
+
+    assert!(rx.is_woken());
+
+    let val = assert_ready_ok!(rx.poll());
+    assert_eq!(val, 1);
+}
+
+#[tokio::test]
+async fn async_send_recv() {
+    let (tx, rx) = oneshot::channel();
+
+    assert_ok!(tx.send(1));
+    assert_eq!(1, assert_ok!(rx.await));
+}
+
+#[test]
+fn close_tx() {
+    let (tx, rx) = oneshot::channel::<i32>();
+    let mut rx = task::spawn(rx);
+
+    assert_pending!(rx.poll());
+
+    drop(tx);
+
+    assert!(rx.is_woken());
+    assert_ready_err!(rx.poll());
+}
+
+#[test]
+fn close_rx() {
+    // First, without checking poll_closed()
+    //
+    let (tx, _) = oneshot::channel();
+
+    assert_err!(tx.send(1));
+
+    // Second, via poll_closed();
+
+    let (tx, rx) = oneshot::channel();
+    let mut tx = task::spawn(tx);
+
+    assert_pending!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    drop(rx);
+
+    assert!(tx.is_woken());
+    assert!(tx.is_closed());
+    assert_ready!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    assert_err!(tx.into_inner().send(1));
+}
+
+#[tokio::test]
+async fn async_rx_closed() {
+    let (mut tx, rx) = oneshot::channel::<()>();
+
+    tokio::spawn(async move {
+        drop(rx);
+    });
+
+    tx.closed().await;
+}
+
+#[test]
+fn explicit_close_poll() {
+    // First, with message sent
+    let (tx, rx) = oneshot::channel();
+    let mut rx = task::spawn(rx);
+
+    assert_ok!(tx.send(1));
+
+    rx.close();
+
+    let value = assert_ready_ok!(rx.poll());
+    assert_eq!(value, 1);
+
+    // Second, without the message sent
+    let (tx, rx) = oneshot::channel::<i32>();
+    let mut tx = task::spawn(tx);
+    let mut rx = task::spawn(rx);
+
+    assert_pending!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    rx.close();
+
+    assert!(tx.is_woken());
+    assert!(tx.is_closed());
+    assert_ready!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    assert_err!(tx.into_inner().send(1));
+    assert_ready_err!(rx.poll());
+
+    // Again, but without sending the value this time
+    let (tx, rx) = oneshot::channel::<i32>();
+    let mut tx = task::spawn(tx);
+    let mut rx = task::spawn(rx);
+
+    assert_pending!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    rx.close();
+
+    assert!(tx.is_woken());
+    assert!(tx.is_closed());
+    assert_ready!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    assert_ready_err!(rx.poll());
+}
+
+#[test]
+fn explicit_close_try_recv() {
+    // First, with message sent
+    let (tx, mut rx) = oneshot::channel();
+
+    assert_ok!(tx.send(1));
+
+    rx.close();
+
+    let val = assert_ok!(rx.try_recv());
+    assert_eq!(1, val);
+
+    // Second, without the message sent
+    let (tx, mut rx) = oneshot::channel::<i32>();
+    let mut tx = task::spawn(tx);
+
+    assert_pending!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    rx.close();
+
+    assert!(tx.is_woken());
+    assert!(tx.is_closed());
+    assert_ready!(tx.enter(|cx, mut tx| tx.poll_closed(cx)));
+
+    assert_err!(rx.try_recv());
+}
+
+#[test]
+#[should_panic]
+fn close_try_recv_poll() {
+    let (_tx, rx) = oneshot::channel::<i32>();
+    let mut rx = task::spawn(rx);
+
+    rx.close();
+
+    assert_err!(rx.try_recv());
+
+    let _ = rx.poll();
+}
+
+#[test]
+fn drops_tasks() {
+    let (mut tx, mut rx) = oneshot::channel::<i32>();
+    let mut tx_task = task::spawn(());
+    let mut rx_task = task::spawn(());
+
+    assert_pending!(tx_task.enter(|cx, _| tx.poll_closed(cx)));
+    assert_pending!(rx_task.enter(|cx, _| Pin::new(&mut rx).poll(cx)));
+
+    drop(tx);
+    drop(rx);
+
+    assert_eq!(1, tx_task.waker_ref_count());
+    assert_eq!(1, rx_task.waker_ref_count());
+}
+
+#[test]
+fn receiver_changes_task() {
+    let (tx, mut rx) = oneshot::channel();
+
+    let mut task1 = task::spawn(());
+    let mut task2 = task::spawn(());
+
+    assert_pending!(task1.enter(|cx, _| Pin::new(&mut rx).poll(cx)));
+
+    assert_eq!(2, task1.waker_ref_count());
+    assert_eq!(1, task2.waker_ref_count());
+
+    assert_pending!(task2.enter(|cx, _| Pin::new(&mut rx).poll(cx)));
+
+    assert_eq!(1, task1.waker_ref_count());
+    assert_eq!(2, task2.waker_ref_count());
+
+    assert_ok!(tx.send(1));
+
+    assert!(!task1.is_woken());
+    assert!(task2.is_woken());
+
+    assert_ready_ok!(task2.enter(|cx, _| Pin::new(&mut rx).poll(cx)));
+}
+
+#[test]
+fn sender_changes_task() {
+    let (mut tx, rx) = oneshot::channel::<i32>();
+
+    let mut task1 = task::spawn(());
+    let mut task2 = task::spawn(());
+
+    assert_pending!(task1.enter(|cx, _| tx.poll_closed(cx)));
+
+    assert_eq!(2, task1.waker_ref_count());
+    assert_eq!(1, task2.waker_ref_count());
+
+    assert_pending!(task2.enter(|cx, _| tx.poll_closed(cx)));
+
+    assert_eq!(1, task1.waker_ref_count());
+    assert_eq!(2, task2.waker_ref_count());
+
+    drop(rx);
+
+    assert!(!task1.is_woken());
+    assert!(task2.is_woken());
+
+    assert_ready!(task2.enter(|cx, _| tx.poll_closed(cx)));
+}