| use core::mem; |
| use core::pin::Pin; |
| use futures_core::future::{FusedFuture, Future}; |
| use futures_core::stream::{FusedStream, TryStream}; |
| use futures_core::task::{Context, Poll}; |
| use pin_project::pin_project; |
| |
| /// Future for the [`try_collect`](super::TryStreamExt::try_collect) method. |
| #[pin_project] |
| #[derive(Debug)] |
| #[must_use = "futures do nothing unless you `.await` or poll them"] |
| pub struct TryCollect<St, C> { |
| #[pin] |
| stream: St, |
| items: C, |
| } |
| |
| impl<St: TryStream, C: Default> TryCollect<St, C> { |
| pub(super) fn new(s: St) -> TryCollect<St, C> { |
| TryCollect { |
| stream: s, |
| items: Default::default(), |
| } |
| } |
| } |
| |
| impl<St, C> FusedFuture for TryCollect<St, C> |
| where |
| St: TryStream + FusedStream, |
| C: Default + Extend<St::Ok>, |
| { |
| fn is_terminated(&self) -> bool { |
| self.stream.is_terminated() |
| } |
| } |
| |
| impl<St, C> Future for TryCollect<St, C> |
| where |
| St: TryStream, |
| C: Default + Extend<St::Ok>, |
| { |
| type Output = Result<C, St::Error>; |
| |
| fn poll( |
| self: Pin<&mut Self>, |
| cx: &mut Context<'_>, |
| ) -> Poll<Self::Output> { |
| let mut this = self.project(); |
| Poll::Ready(Ok(loop { |
| match ready!(this.stream.as_mut().try_poll_next(cx)?) { |
| Some(x) => this.items.extend(Some(x)), |
| None => break mem::replace(this.items, Default::default()), |
| } |
| })) |
| } |
| } |