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    use super::assert_stream;
    use core::pin::Pin;
    use futures_core::stream::{Stream, FusedStream};
    use futures_core::task::{Context, Poll};

    /// Stream for the [`repeat`] function.
    #[derive(Debug, Clone)]
    #[must_use = "streams do nothing unless polled"]
    pub struct Repeat<T> {
        item: T,
    }

    /// Create a stream which produces the same item repeatedly.
    ///
    /// The stream never terminates. Note that you likely want to avoid
    /// usage of `collect` or such on the returned stream as it will exhaust
    /// available memory as it tries to just fill up all RAM.
    ///
    /// ```
    /// # futures::executor::block_on(async {
    /// use futures::stream::{self, StreamExt};
    ///
    /// let stream = stream::repeat(9);
    /// assert_eq!(vec![9, 9, 9], stream.take(3).collect::<Vec<i32>>().await);
    /// # });
    /// ```
    pub fn repeat<T>(item: T) -> Repeat<T>
        where T: Clone
    {
        assert_stream::<T, _>(Repeat { item })
    }

    impl<T> Unpin for Repeat<T> {}

    impl<T> Stream for Repeat<T>
        where T: Clone
    {
        type Item = T;

        fn poll_next(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Option<Self::Item>> {
            Poll::Ready(Some(self.item.clone()))
        }

        fn size_hint(&self) -> (usize, Option<usize>) {
            (usize::max_value(), None)
        }
    }

    impl<T> FusedStream for Repeat<T>
        where T: Clone,
    {
        fn is_terminated(&self) -> bool {
            false
        }
    }