use std::future::Future;
use std::pin::Pin;
use std::task::{Context, Poll};
pub fn poll<T>(future: &mut impl Future<Output = T>) -> Poll<T> {
let waker = noop_waker::noop_waker();
let mut context = Context::from_waker(&waker);
let future = unsafe { Pin::new_unchecked(future) };
future.poll(&mut context)
}
#[cfg(test)]
mod tests {
use super::*;
struct Yield {
yielded: bool,
}
impl Future for Yield {
type Output = ();
fn poll(mut self: Pin<&mut Self>, context: &mut Context<'_>) -> Poll<Self::Output> {
if self.yielded {
return Poll::Ready(());
}
self.yielded = true;
context.waker().wake_by_ref();
Poll::Pending
}
}
#[test]
fn poll_drives_future() {
let mut future = Yield { yielded: false };
assert_eq!(poll(&mut future), Poll::Pending);
assert_eq!(poll(&mut future), Poll::Ready(()));
}
}