1use std::future::Future;
2use std::pin::Pin;
3use std::task::{Context, Poll};
4
5use futures_util::{ready, TryFuture};
6use pin_project::pin_project;
7
8use super::{Either, Filter, FilterBase, Internal, Tuple};
9
10#[derive(Clone, Copy, Debug)]
11pub struct Unify<F> {
12 pub(super) filter: F,
13}
14
15impl<F, T> FilterBase for Unify<F>
16where
17 F: Filter<Extract = (Either<T, T>,)>,
18 T: Tuple,
19{
20 type Extract = T;
21 type Error = F::Error;
22 type Future = UnifyFuture<F::Future>;
23 #[inline]
24 fn filter(&self, _: Internal) -> Self::Future {
25 UnifyFuture {
26 inner: self.filter.filter(Internal),
27 }
28 }
29}
30
31#[allow(missing_debug_implementations)]
32#[pin_project]
33pub struct UnifyFuture<F> {
34 #[pin]
35 inner: F,
36}
37
38impl<F, T> Future for UnifyFuture<F>
39where
40 F: TryFuture<Ok = (Either<T, T>,)>,
41{
42 type Output = Result<T, F::Error>;
43
44 #[inline]
45 fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
46 Poll::Ready(match ready!(self.project().inner.try_poll(cx))? {
47 (Either::A(x),) | (Either::B(x),) => Ok(x),
48 })
49 }
50}