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//@ build-pass (FIXME(62277): could be check-pass?)
//@ edition:2018
//@ compile-flags: --crate-type lib
use std::{
cell::RefCell,
fmt::Debug,
rc::Rc,
};
fn non_sync() -> impl Debug { RefCell::new(()) }
fn non_send() -> impl Debug { Rc::new(()) }
fn take_ref<T>(_: &T) {}
async fn fut() {}
async fn fut_arg<T>(_: T) {}
async fn still_send() {
fut().await;
println!("{:?} {:?}", non_send(), non_sync());
fut().await;
drop(non_send());
drop(non_sync());
fut().await;
fut_arg(non_sync()).await;
// Note: all temporaries in `if let` and `match` scrutinee
// are dropped at the *end* of the blocks, so using `non_send()`
// in either of those positions with an await in the middle will
// cause a `!Send` future. It might be nice in the future to allow
// this for `Copy` types, since they can be "dropped" early without
// affecting the end user.
if let Some(_) = Some(non_sync()) {
fut().await;
}
match Some(non_sync()) {
Some(_) => fut().await,
None => fut().await,
}
let _ = non_send();
fut().await;
{
let _x = non_send();
}
fut().await;
}
fn assert_send(_: impl Send) {}
pub fn pass_assert() {
assert_send(still_send());
}
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