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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /third_party/rust/futures/tests/eager_drop.rs
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/futures/tests/eager_drop.rs')
-rw-r--r--third_party/rust/futures/tests/eager_drop.rs121
1 files changed, 121 insertions, 0 deletions
diff --git a/third_party/rust/futures/tests/eager_drop.rs b/third_party/rust/futures/tests/eager_drop.rs
new file mode 100644
index 0000000000..992507774c
--- /dev/null
+++ b/third_party/rust/futures/tests/eager_drop.rs
@@ -0,0 +1,121 @@
+use futures::channel::oneshot;
+use futures::future::{self, Future, FutureExt, TryFutureExt};
+use futures::task::{Context, Poll};
+use futures_test::future::FutureTestExt;
+use pin_project::pin_project;
+use std::pin::Pin;
+use std::sync::mpsc;
+
+#[test]
+fn map_ok() {
+ // The closure given to `map_ok` should have been dropped by the time `map`
+ // runs.
+ let (tx1, rx1) = mpsc::channel::<()>();
+ let (tx2, rx2) = mpsc::channel::<()>();
+
+ future::ready::<Result<i32, i32>>(Err(1))
+ .map_ok(move |_| {
+ let _tx1 = tx1;
+ panic!("should not run");
+ })
+ .map(move |_| {
+ assert!(rx1.recv().is_err());
+ tx2.send(()).unwrap()
+ })
+ .run_in_background();
+
+ rx2.recv().unwrap();
+}
+
+#[test]
+fn map_err() {
+ // The closure given to `map_err` should have been dropped by the time `map`
+ // runs.
+ let (tx1, rx1) = mpsc::channel::<()>();
+ let (tx2, rx2) = mpsc::channel::<()>();
+
+ future::ready::<Result<i32, i32>>(Ok(1))
+ .map_err(move |_| {
+ let _tx1 = tx1;
+ panic!("should not run");
+ })
+ .map(move |_| {
+ assert!(rx1.recv().is_err());
+ tx2.send(()).unwrap()
+ })
+ .run_in_background();
+
+ rx2.recv().unwrap();
+}
+
+#[pin_project]
+struct FutureData<F, T> {
+ _data: T,
+ #[pin]
+ future: F,
+}
+
+impl<F: Future, T: Send + 'static> Future for FutureData<F, T> {
+ type Output = F::Output;
+
+ fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<F::Output> {
+ self.project().future.poll(cx)
+ }
+}
+
+#[test]
+fn then_drops_eagerly() {
+ let (tx0, rx0) = oneshot::channel::<()>();
+ let (tx1, rx1) = mpsc::channel::<()>();
+ let (tx2, rx2) = mpsc::channel::<()>();
+
+ FutureData { _data: tx1, future: rx0.unwrap_or_else(|_| panic!()) }
+ .then(move |_| {
+ assert!(rx1.recv().is_err()); // tx1 should have been dropped
+ tx2.send(()).unwrap();
+ future::ready(())
+ })
+ .run_in_background();
+
+ assert_eq!(Err(mpsc::TryRecvError::Empty), rx2.try_recv());
+ tx0.send(()).unwrap();
+ rx2.recv().unwrap();
+}
+
+#[test]
+fn and_then_drops_eagerly() {
+ let (tx0, rx0) = oneshot::channel::<Result<(), ()>>();
+ let (tx1, rx1) = mpsc::channel::<()>();
+ let (tx2, rx2) = mpsc::channel::<()>();
+
+ FutureData { _data: tx1, future: rx0.unwrap_or_else(|_| panic!()) }
+ .and_then(move |_| {
+ assert!(rx1.recv().is_err()); // tx1 should have been dropped
+ tx2.send(()).unwrap();
+ future::ready(Ok(()))
+ })
+ .run_in_background();
+
+ assert_eq!(Err(mpsc::TryRecvError::Empty), rx2.try_recv());
+ tx0.send(Ok(())).unwrap();
+ rx2.recv().unwrap();
+}
+
+#[test]
+fn or_else_drops_eagerly() {
+ let (tx0, rx0) = oneshot::channel::<Result<(), ()>>();
+ let (tx1, rx1) = mpsc::channel::<()>();
+ let (tx2, rx2) = mpsc::channel::<()>();
+
+ FutureData { _data: tx1, future: rx0.unwrap_or_else(|_| panic!()) }
+ .or_else(move |_| {
+ assert!(rx1.recv().is_err()); // tx1 should have been dropped
+ tx2.send(()).unwrap();
+ future::ready::<Result<(), ()>>(Ok(()))
+ })
+ .run_in_background();
+
+ assert_eq!(Err(mpsc::TryRecvError::Empty), rx2.try_recv());
+ tx0.send(Err(())).unwrap();
+ rx2.recv().unwrap();
+}