1 files changed, 43 insertions, 0 deletions
diff --git a/third_party/rust/futures-0.1.31/tests/future_flatten_stream.rs b/third_party/rust/futures-0.1.31/tests/future_flatten_stream.rs
new file mode 100644
index 0000000000..442d381fd7
--- /dev/null
+++ b/third_party/rust/futures-0.1.31/tests/future_flatten_stream.rs
@@ -0,0 +1,43 @@
+extern crate core;
+extern crate futures;
+
+use core::marker;
+
+use futures::prelude::*;
+use futures::future::{ok, err};
+use futures::stream;
+
+#[test]
+fn successful_future() {
+    let stream_items = vec![17, 19];
+    let future_of_a_stream = ok::<_, bool>(stream::iter_ok(stream_items));
+
+    let stream = future_of_a_stream.flatten_stream();
+
+    let mut iter = stream.wait();
+    assert_eq!(Ok(17), iter.next().unwrap());
+    assert_eq!(Ok(19), iter.next().unwrap());
+    assert_eq!(None, iter.next());
+}
+
+struct PanickingStream<T, E> {
+    _marker: marker::PhantomData<(T, E)>
+}
+
+impl<T, E> Stream for PanickingStream<T, E> {
+    type Item = T;
+    type Error = E;
+
+    fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
+        panic!()
+    }
+}
+
+#[test]
+fn failed_future() {
+    let future_of_a_stream = err::<PanickingStream<bool, u32>, _>(10);
+    let stream = future_of_a_stream.flatten_stream();
+    let mut iter = stream.wait();
+    assert_eq!(Err(10), iter.next().unwrap());
+    assert_eq!(None, iter.next());
+}