fast-down-api 0.1.1

A convenient and easy-to-use FFI wrapper for fast-down
Documentation 
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use std::pin::Pin;
use std::task::{Context, Poll};

pub struct ForceSend<F>(pub F);

#[allow(clippy::non_send_fields_in_send_ty)]
unsafe impl<F> Send for ForceSend<F> {}

impl<F: Future> Future for ForceSend<F> {
    type Output = F::Output;
    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
        unsafe { self.map_unchecked_mut(|s| &mut s.0).poll(cx) }
    }
}

pub trait ForceSendExt {
    fn force_send(self) -> ForceSend<Self>
    where
        Self: Sized,
    {
        ForceSend(self)
    }
}

impl<F> ForceSendExt for F {
    fn force_send(self) -> ForceSend<Self> {
        ForceSend(self)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use std::future;

    #[tokio::test]
    async fn force_send_awaits_inner_future() {
        let wrapped = ForceSend(future::ready(7u32));
        assert_eq!(wrapped.await, 7);
    }

    #[tokio::test]
    async fn force_send_ext_transfers_poll_to_inner() {
        let wrapped = future::ready(123u32).force_send();
        assert_eq!(wrapped.await, 123);
    }

    #[test]
    fn force_send_ext_constructs_wrapper() {
        let w = "hello".to_string().force_send();
        assert_eq!(w.0, "hello");
    }
}