use std::fmt::{self, Debug, Formatter};
use std::marker::PhantomData;
use std::pin::Pin;
use std::task::{Context, Poll};
use futures_core::future::{FusedFuture, Future};
use crate::{FusedMultipartWrite, MultipartWrite};
#[must_use = "futures do nothing unless polled"]
pub struct Flush<'a, Wr: ?Sized, Part> {
writer: &'a mut Wr,
_p: PhantomData<fn(Part)>,
}
impl<Wr: ?Sized + Unpin, Part> Unpin for Flush<'_, Wr, Part> {}
impl<'a, Wr: ?Sized + MultipartWrite<Part> + Unpin, Part> Flush<'a, Wr, Part> {
pub(super) fn new(writer: &'a mut Wr) -> Self {
Self { writer, _p: std::marker::PhantomData }
}
}
impl<Wr, Part> FusedFuture for Flush<'_, Wr, Part>
where
Wr: FusedMultipartWrite<Part> + Unpin,
{
fn is_terminated(&self) -> bool {
self.writer.is_terminated()
}
}
impl<Wr: MultipartWrite<Part> + Unpin, Part> Future for Flush<'_, Wr, Part> {
type Output = Result<(), Wr::Error>;
fn poll(
mut self: Pin<&mut Self>,
cx: &mut Context<'_>,
) -> Poll<Self::Output> {
Pin::new(&mut self.writer).poll_flush(cx)
}
}
impl<Wr: Debug, Part> Debug for Flush<'_, Wr, Part> {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
f.debug_struct("Flush").field("writer", &self.writer).finish()
}
}