stream: iter() should yield every so often. (#2343)

1 files changed, 18 insertions, 0 deletions

diff --git a/tokio/tests/stream_iter.rs b/tokio/tests/stream_iter.rs
new file mode 100644
index 00000000..45148a7a
--- /dev/null
+++ b/tokio/tests/stream_iter.rs
@@ -0,0 +1,18 @@
+use tokio::stream;
+use tokio_test::task;
+
+use std::iter;
+
+#[tokio::test]
+async fn coop() {
+    let mut stream = task::spawn(stream::iter(iter::repeat(1)));
+
+    for _ in 0..10_000 {
+        if stream.poll_next().is_pending() {
+            assert!(stream.is_woken());
+            return;
+        }
+    }
+
+    panic!("did not yield");
+}