1 files changed, 30 insertions, 0 deletions
diff --git a/third_party/rust/tokio/src/stream/try_next.rs b/third_party/rust/tokio/src/stream/try_next.rs
new file mode 100644
index 0000000000..59e0eb1a41
--- /dev/null
+++ b/third_party/rust/tokio/src/stream/try_next.rs
@@ -0,0 +1,30 @@
+use crate::stream::{Next, Stream};
+
+use core::future::Future;
+use core::pin::Pin;
+use core::task::{Context, Poll};
+
+/// Future for the [`try_next`](super::StreamExt::try_next) method.
+#[derive(Debug)]
+#[must_use = "futures do nothing unless you `.await` or poll them"]
+pub struct TryNext<'a, St: ?Sized> {
+    inner: Next<'a, St>,
+}
+
+impl<St: ?Sized + Unpin> Unpin for TryNext<'_, St> {}
+
+impl<'a, St: ?Sized> TryNext<'a, St> {
+    pub(super) fn new(stream: &'a mut St) -> Self {
+        Self {
+            inner: Next::new(stream),
+        }
+    }
+}
+
+impl<T, E, St: ?Sized + Stream<Item = Result<T, E>> + Unpin> Future for TryNext<'_, St> {
+    type Output = Result<Option<T>, E>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        Pin::new(&mut self.inner).poll(cx).map(Option::transpose)
+    }
+}