mirror of https://github.com/helix-editor/helix
Remove select_all implementation
parent
29b9eed33c
commit
d55419604c
@ -1,143 +0,0 @@
|
|||||||
//! An unbounded set of streams
|
|
||||||
|
|
||||||
use core::{
|
|
||||||
fmt::{self, Debug},
|
|
||||||
iter::FromIterator,
|
|
||||||
pin::Pin,
|
|
||||||
};
|
|
||||||
|
|
||||||
use std::task::{Context, Poll};
|
|
||||||
|
|
||||||
use futures_util::stream::{FusedStream, FuturesUnordered, StreamExt, StreamFuture};
|
|
||||||
use futures_util::{ready, stream::Stream};
|
|
||||||
|
|
||||||
/// An unbounded set of streams
|
|
||||||
///
|
|
||||||
/// This "combinator" provides the ability to maintain a set of streams
|
|
||||||
/// and drive them all to completion.
|
|
||||||
///
|
|
||||||
/// Streams are pushed into this set and their realized values are
|
|
||||||
/// yielded as they become ready. Streams will only be polled when they
|
|
||||||
/// generate notifications. This allows to coordinate a large number of streams.
|
|
||||||
///
|
|
||||||
/// Note that you can create a ready-made `SelectAll` via the
|
|
||||||
/// `select_all` function in the `stream` module, or you can start with an
|
|
||||||
/// empty set with the `SelectAll::new` constructor.
|
|
||||||
#[must_use = "streams do nothing unless polled"]
|
|
||||||
pub struct SelectAll<St> {
|
|
||||||
inner: FuturesUnordered<StreamFuture<St>>,
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Debug> Debug for SelectAll<St> {
|
|
||||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
||||||
write!(f, "SelectAll {{ ... }}")
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> SelectAll<St> {
|
|
||||||
/// Constructs a new, empty `SelectAll`
|
|
||||||
///
|
|
||||||
/// The returned `SelectAll` does not contain any streams and, in this
|
|
||||||
/// state, `SelectAll::poll` will return `Poll::Ready(None)`.
|
|
||||||
pub fn new() -> Self {
|
|
||||||
Self {
|
|
||||||
inner: FuturesUnordered::new(),
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Returns the number of streams contained in the set.
|
|
||||||
///
|
|
||||||
/// This represents the total number of in-flight streams.
|
|
||||||
pub fn len(&self) -> usize {
|
|
||||||
self.inner.len()
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Returns `true` if the set contains no streams
|
|
||||||
pub fn is_empty(&self) -> bool {
|
|
||||||
self.inner.is_empty()
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Push a stream into the set.
|
|
||||||
///
|
|
||||||
/// This function submits the given stream to the set for managing. This
|
|
||||||
/// function will not call `poll` on the submitted stream. The caller must
|
|
||||||
/// ensure that `SelectAll::poll` is called in order to receive task
|
|
||||||
/// notifications.
|
|
||||||
pub fn push(&self, stream: St) {
|
|
||||||
self.inner.push(stream.into_future());
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> Default for SelectAll<St> {
|
|
||||||
fn default() -> Self {
|
|
||||||
Self::new()
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> Stream for SelectAll<St> {
|
|
||||||
type Item = St::Item;
|
|
||||||
|
|
||||||
fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
|
|
||||||
loop {
|
|
||||||
match ready!(self.inner.poll_next_unpin(cx)) {
|
|
||||||
Some((Some(item), remaining)) => {
|
|
||||||
self.push(remaining);
|
|
||||||
return Poll::Ready(Some(item));
|
|
||||||
}
|
|
||||||
Some((None, _)) => {
|
|
||||||
// `FuturesUnordered` thinks it isn't terminated
|
|
||||||
// because it yielded a Some.
|
|
||||||
// We do not return, but poll `FuturesUnordered`
|
|
||||||
// in the next loop iteration.
|
|
||||||
}
|
|
||||||
None => return Poll::Ready(None),
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> FusedStream for SelectAll<St> {
|
|
||||||
fn is_terminated(&self) -> bool {
|
|
||||||
self.inner.is_terminated()
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
/// Convert a list of streams into a `Stream` of results from the streams.
|
|
||||||
///
|
|
||||||
/// This essentially takes a list of streams (e.g. a vector, an iterator, etc.)
|
|
||||||
/// and bundles them together into a single stream.
|
|
||||||
/// The stream will yield items as they become available on the underlying
|
|
||||||
/// streams internally, in the order they become available.
|
|
||||||
///
|
|
||||||
/// Note that the returned set can also be used to dynamically push more
|
|
||||||
/// futures into the set as they become available.
|
|
||||||
///
|
|
||||||
/// This function is only available when the `std` or `alloc` feature of this
|
|
||||||
/// library is activated, and it is activated by default.
|
|
||||||
pub fn select_all<I>(streams: I) -> SelectAll<I::Item>
|
|
||||||
where
|
|
||||||
I: IntoIterator,
|
|
||||||
I::Item: Stream + Unpin,
|
|
||||||
{
|
|
||||||
let set = SelectAll::new();
|
|
||||||
|
|
||||||
for stream in streams {
|
|
||||||
set.push(stream);
|
|
||||||
}
|
|
||||||
|
|
||||||
set
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> FromIterator<St> for SelectAll<St> {
|
|
||||||
fn from_iter<T: IntoIterator<Item = St>>(iter: T) -> Self {
|
|
||||||
select_all(iter)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl<St: Stream + Unpin> Extend<St> for SelectAll<St> {
|
|
||||||
fn extend<T: IntoIterator<Item = St>>(&mut self, iter: T) {
|
|
||||||
for st in iter {
|
|
||||||
self.push(st)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
Loading…
Reference in New Issue