rust/tests/ui/async-await/async-fn/auxiliary/block-on.rs

21 lines
458 B
Rust

//@ edition: 2021
#![feature(async_closure, noop_waker)]
use std::future::Future;
use std::pin::pin;
use std::task::*;
pub fn block_on<T>(fut: impl Future<Output = T>) -> T {
let mut fut = pin!(fut);
// Poll loop, just to test the future...
let ctx = &mut Context::from_waker(Waker::noop());
loop {
match unsafe { fut.as_mut().poll(ctx) } {
Poll::Pending => {}
Poll::Ready(t) => break t,
}
}
}