blob: ad48165ec090f54281215f1d459299fb36c6abbf [file] [log] [blame]
use core::marker::Unpin;
use core::mem::PinMut;
use futures_core::future::Future;
use futures_core::task::{self, Poll};
use futures_sink::Sink;
/// Future for the `flush` combinator, which polls the sink until all data
/// has been flushed.
#[derive(Debug)]
#[must_use = "futures do nothing unless polled"]
pub struct Flush<'a, Si: 'a + Unpin + ?Sized> {
sink: &'a mut Si,
}
// Pin is never projected to a field.
impl<Si: Unpin + ?Sized> Unpin for Flush<'_, Si> {}
/// A future that completes when the sink has finished processing all
/// pending requests.
///
/// The sink itself is returned after flushing is complete; this adapter is
/// intended to be used when you want to stop sending to the sink until
/// all current requests are processed.
impl<'a, Si: Sink + Unpin + ?Sized> Flush<'a, Si> {
pub(super) fn new(sink: &'a mut Si) -> Self {
Flush { sink }
}
}
impl<Si: Sink + Unpin + ?Sized> Future for Flush<'_, Si> {
type Output = Result<(), Si::SinkError>;
fn poll(
mut self: PinMut<Self>,
cx: &mut task::Context,
) -> Poll<Self::Output> {
PinMut::new(&mut self.sink).poll_flush(cx)
}
}