diff options
Diffstat (limited to 'vendor/futures/tests/future_try_flatten_stream.rs')
-rw-r--r-- | vendor/futures/tests/future_try_flatten_stream.rs | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/vendor/futures/tests/future_try_flatten_stream.rs b/vendor/futures/tests/future_try_flatten_stream.rs new file mode 100644 index 000000000..82ae1baf2 --- /dev/null +++ b/vendor/futures/tests/future_try_flatten_stream.rs @@ -0,0 +1,83 @@ +use futures::executor::block_on_stream; +use futures::future::{err, ok, TryFutureExt}; +use futures::sink::Sink; +use futures::stream::Stream; +use futures::stream::{self, StreamExt}; +use futures::task::{Context, Poll}; +use std::marker::PhantomData; +use std::pin::Pin; + +#[test] +fn successful_future() { + let stream_items = vec![17, 19]; + let future_of_a_stream = ok::<_, bool>(stream::iter(stream_items).map(Ok)); + + let stream = future_of_a_stream.try_flatten_stream(); + + let mut iter = block_on_stream(stream); + assert_eq!(Ok(17), iter.next().unwrap()); + assert_eq!(Ok(19), iter.next().unwrap()); + assert_eq!(None, iter.next()); +} + +#[test] +fn failed_future() { + struct PanickingStream<T, E> { + _marker: PhantomData<(T, E)>, + } + + impl<T, E> Stream for PanickingStream<T, E> { + type Item = Result<T, E>; + + fn poll_next(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> { + panic!() + } + } + + let future_of_a_stream = err::<PanickingStream<bool, u32>, _>(10); + let stream = future_of_a_stream.try_flatten_stream(); + let mut iter = block_on_stream(stream); + assert_eq!(Err(10), iter.next().unwrap()); + assert_eq!(None, iter.next()); +} + +#[test] +fn assert_impls() { + struct StreamSink<T, E, Item>(PhantomData<(T, E, Item)>); + + impl<T, E, Item> Stream for StreamSink<T, E, Item> { + type Item = Result<T, E>; + fn poll_next(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> { + panic!() + } + } + + impl<T, E, Item> Sink<Item> for StreamSink<T, E, Item> { + type Error = E; + fn poll_ready(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), Self::Error>> { + panic!() + } + fn start_send(self: Pin<&mut Self>, _: Item) -> Result<(), Self::Error> { + panic!() + } + fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), Self::Error>> { + panic!() + } + fn poll_close(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), Self::Error>> { + panic!() + } + } + + fn assert_stream<S: Stream>(_: &S) {} + fn assert_sink<S: Sink<Item>, Item>(_: &S) {} + fn assert_stream_sink<S: Stream + Sink<Item>, Item>(_: &S) {} + + let s = ok(StreamSink::<(), (), ()>(PhantomData)).try_flatten_stream(); + assert_stream(&s); + assert_sink(&s); + assert_stream_sink(&s); + let s = ok(StreamSink::<(), (), ()>(PhantomData)).flatten_sink(); + assert_stream(&s); + assert_sink(&s); + assert_stream_sink(&s); +} |