34 lines
752 B
Rust
34 lines
752 B
Rust
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//@ known-bug: #124020
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//@ compile-flags: -Zpolymorphize=on --edition=2018 --crate-type=lib
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#![feature(async_closure, noop_waker, async_fn_traits)]
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use std::future::Future;
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use std::pin::pin;
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use std::task::*;
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pub fn block_on<T>(fut: impl Future<Output = T>) -> T {
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let mut fut = pin!(fut);
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let ctx = &mut Context::from_waker(Waker::noop());
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loop {
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match fut.as_mut().poll(ctx) {
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Poll::Pending => {}
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Poll::Ready(t) => break t,
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}
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}
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}
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async fn call_once(f: impl async FnOnce(DropMe)) {
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f(DropMe("world")).await;
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}
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struct DropMe(&'static str);
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pub fn future() {
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block_on(async {
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let async_closure = async move |a: DropMe| {};
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call_once(async_closure).await;
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});
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}
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