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-rw-r--r--third_party/rust/tokio-stream/src/stream_ext/any.rs58
1 files changed, 58 insertions, 0 deletions
diff --git a/third_party/rust/tokio-stream/src/stream_ext/any.rs b/third_party/rust/tokio-stream/src/stream_ext/any.rs
new file mode 100644
index 0000000000..31394f249b
--- /dev/null
+++ b/third_party/rust/tokio-stream/src/stream_ext/any.rs
@@ -0,0 +1,58 @@
+use crate::Stream;
+
+use core::future::Future;
+use core::marker::PhantomPinned;
+use core::pin::Pin;
+use core::task::{Context, Poll};
+use pin_project_lite::pin_project;
+
+pin_project! {
+ /// Future for the [`any`](super::StreamExt::any) method.
+ #[derive(Debug)]
+ #[must_use = "futures do nothing unless you `.await` or poll them"]
+ pub struct AnyFuture<'a, St: ?Sized, F> {
+ stream: &'a mut St,
+ f: F,
+ // Make this future `!Unpin` for compatibility with async trait methods.
+ #[pin]
+ _pin: PhantomPinned,
+ }
+}
+
+impl<'a, St: ?Sized, F> AnyFuture<'a, St, F> {
+ pub(super) fn new(stream: &'a mut St, f: F) -> Self {
+ Self {
+ stream,
+ f,
+ _pin: PhantomPinned,
+ }
+ }
+}
+
+impl<St, F> Future for AnyFuture<'_, St, F>
+where
+ St: ?Sized + Stream + Unpin,
+ F: FnMut(St::Item) -> bool,
+{
+ type Output = bool;
+
+ fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+ let me = self.project();
+ let mut stream = Pin::new(me.stream);
+
+ // Take a maximum of 32 items from the stream before yielding.
+ for _ in 0..32 {
+ match futures_core::ready!(stream.as_mut().poll_next(cx)) {
+ Some(v) => {
+ if (me.f)(v) {
+ return Poll::Ready(true);
+ }
+ }
+ None => return Poll::Ready(false),
+ }
+ }
+
+ cx.waker().wake_by_ref();
+ Poll::Pending
+ }
+}