// abusing feature for disabling multithreading in miri
#![cfg(feature = "futures")]
#![feature(generators, never_type)]

use std::thread;
use std::time::Duration;

#[derive(Debug)]
struct LongComputation;

impl eff::Effect for LongComputation {
    type Output = u32;
}

#[test]
fn test_multithread() {
    #[eff::eff(LongComputation)]
    fn computation() -> u32 {
        eff::perform!(LongComputation) + 100
    }

    use eff::Effectful;

    assert_eq!(
        computation()
            .handle(eff::handler! {
                x => x,
                LongComputation, k => {
                    thread::spawn({
                        let waker = k.waker();
                        move || {
                            thread::sleep(Duration::from_millis(500));
                            waker.wake(42)
                        }
                    });
                    eff::perform!(k.continuation()) + 200
                }
            })
            .block_on(),
        342,
    );
}