futures_test/stream/
mod.rs

1//! Additional combinators for testing streams.
2
3use futures_core::stream::Stream;
4
5pub use crate::interleave_pending::InterleavePending;
6
7/// Additional combinators for testing streams.
8pub trait StreamTestExt: Stream {
9    /// Introduces an extra [`Poll::Pending`](futures_core::task::Poll::Pending)
10    /// in between each item of the stream.
11    ///
12    /// # Examples
13    ///
14    /// ```
15    /// use futures::task::Poll;
16    /// use futures::stream::{self, Stream};
17    /// use futures_test::task::noop_context;
18    /// use futures_test::stream::StreamTestExt;
19    /// use futures::pin_mut;
20    ///
21    /// let stream = stream::iter(vec![1, 2]).interleave_pending();
22    /// pin_mut!(stream);
23    ///
24    /// let mut cx = noop_context();
25    ///
26    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Pending);
27    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Ready(Some(1)));
28    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Pending);
29    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Ready(Some(2)));
30    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Pending);
31    /// assert_eq!(stream.as_mut().poll_next(&mut cx), Poll::Ready(None));
32    /// ```
33    fn interleave_pending(self) -> InterleavePending<Self>
34    where
35        Self: Sized,
36    {
37        InterleavePending::new(self)
38    }
39}
40
41impl<St> StreamTestExt for St where St: Stream {}
futures_test/stream/mod.rs

futures_test/stream/
mod.rs
