1//! Future types
2
3use super::error::Elapsed;
4use pin_project_lite::pin_project;
5use std::{
6 future::Future,
7 pin::Pin,
8 task::{Context, Poll},
9};
10use tokio::time::Sleep;
11
12pin_project! {
13 /// [`Timeout`] response future
14 ///
15 /// [`Timeout`]: crate::timeout::Timeout
16 #[derive(Debug)]
17 pub struct ResponseFuture<T> {
18 #[pin]
19 response: T,
20 #[pin]
21 sleep: Sleep,
22 }
23}
24
25impl<T> ResponseFuture<T> {
26 pub(crate) fn new(response: T, sleep: Sleep) -> Self {
27 ResponseFuture { response, sleep }
28 }
29}
30
31impl<F, T, E> Future for ResponseFuture<F>
32where
33 F: Future<Output = Result<T, E>>,
34 E: Into<crate::BoxError>,
35{
36 type Output = Result<T, crate::BoxError>;
37
38 fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
39 let this: Projection<'_, F> = self.project();
40
41 // First, try polling the future
42 match this.response.poll(cx) {
43 Poll::Ready(v: Result) => return Poll::Ready(v.map_err(op:Into::into)),
44 Poll::Pending => {}
45 }
46
47 // Now check the sleep
48 match this.sleep.poll(cx) {
49 Poll::Pending => Poll::Pending,
50 Poll::Ready(_) => Poll::Ready(Err(Elapsed(()).into())),
51 }
52 }
53}
54