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// run-pass
// revisions: default nomiropt
//[nomiropt]compile-flags: -Z mir-opt-level=0
#![feature(generators, generator_trait)]
use std::fmt::Debug;
use std::marker::Unpin;
use std::ops::{
Generator,
GeneratorState::{self, *},
};
use std::pin::Pin;
use std::sync::atomic::{AtomicUsize, Ordering};
fn drain<G: Generator<R, Yield = Y> + Unpin, R, Y>(
gen: &mut G,
inout: Vec<(R, GeneratorState<Y, G::Return>)>,
) where
Y: Debug + PartialEq,
G::Return: Debug + PartialEq,
{
let mut gen = Pin::new(gen);
for (input, out) in inout {
assert_eq!(gen.as_mut().resume(input), out);
}
}
static DROPS: AtomicUsize = AtomicUsize::new(0);
#[derive(Debug, PartialEq)]
struct DropMe;
impl Drop for DropMe {
fn drop(&mut self) {
DROPS.fetch_add(1, Ordering::SeqCst);
}
}
fn expect_drops<T>(expected_drops: usize, f: impl FnOnce() -> T) -> T {
DROPS.store(0, Ordering::SeqCst);
let res = f();
let actual_drops = DROPS.load(Ordering::SeqCst);
assert_eq!(actual_drops, expected_drops);
res
}
fn main() {
drain(
&mut |mut b| {
while b != 0 {
b = yield (b + 1);
}
-1
},
vec![(1, Yielded(2)), (-45, Yielded(-44)), (500, Yielded(501)), (0, Complete(-1))],
);
expect_drops(2, || drain(&mut |a| yield a, vec![(DropMe, Yielded(DropMe))]));
expect_drops(6, || {
drain(
&mut |a| yield yield a,
vec![(DropMe, Yielded(DropMe)), (DropMe, Yielded(DropMe)), (DropMe, Complete(DropMe))],
)
});
#[allow(unreachable_code)]
expect_drops(2, || drain(&mut |a| yield return a, vec![(DropMe, Complete(DropMe))]));
expect_drops(2, || {
drain(
&mut |a: DropMe| {
if false { yield () } else { a }
},
vec![(DropMe, Complete(DropMe))],
)
});
expect_drops(4, || {
drain(
#[allow(unused_assignments, unused_variables)]
&mut |mut a: DropMe| {
a = yield;
a = yield;
a = yield;
},
vec![
(DropMe, Yielded(())),
(DropMe, Yielded(())),
(DropMe, Yielded(())),
(DropMe, Complete(())),
],
)
});
}
|
