blob: 5a2974b0d59caa70ed24687adc0fa5b23e32b1cb [file] [log] [blame]
use core::marker::Unpin;
use core::mem::PinMut;
use futures_core::future::Future;
use futures_core::task::{self, Poll};
use pin_utils::unsafe_pinned;
/// Future for the `unit_error` combinator, turning a `Future` into a `TryFuture`.
///
/// This is created by the `FutureExt::unit_error` method.
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct UnitError<Fut> {
future: Fut,
}
impl<Fut> UnitError<Fut> {
unsafe_pinned!(future: Fut);
/// Creates a new UnitError.
pub(super) fn new(future: Fut) -> UnitError<Fut> {
UnitError { future }
}
}
impl<Fut: Unpin> Unpin for UnitError<Fut> {}
impl<Fut, T> Future for UnitError<Fut>
where Fut: Future<Output = T>,
{
type Output = Result<T, ()>;
fn poll(mut self: PinMut<Self>, cx: &mut task::Context) -> Poll<Result<T, ()>> {
self.future().poll(cx).map(Ok)
}
}