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//! Tests for the list channel flavor.
use std::any::Any;
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering;
use std::thread;
use std::time::Duration;
use crossbeam_channel::{select, unbounded, Receiver};
use crossbeam_channel::{RecvError, RecvTimeoutError, TryRecvError};
use crossbeam_channel::{SendError, SendTimeoutError, TrySendError};
use crossbeam_utils::thread::scope;
use rand::{thread_rng, Rng};
fn ms(ms: u64) -> Duration {
Duration::from_millis(ms)
}
#[test]
fn smoke() {
let (s, r) = unbounded();
s.try_send(7).unwrap();
assert_eq!(r.try_recv(), Ok(7));
s.send(8).unwrap();
assert_eq!(r.recv(), Ok(8));
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
assert_eq!(r.recv_timeout(ms(1000)), Err(RecvTimeoutError::Timeout));
}
#[test]
fn capacity() {
let (s, r) = unbounded::<()>();
assert_eq!(s.capacity(), None);
assert_eq!(r.capacity(), None);
}
#[test]
fn len_empty_full() {
let (s, r) = unbounded();
assert_eq!(s.len(), 0);
assert!(s.is_empty());
assert!(!s.is_full());
assert_eq!(r.len(), 0);
assert!(r.is_empty());
assert!(!r.is_full());
s.send(()).unwrap();
assert_eq!(s.len(), 1);
assert!(!s.is_empty());
assert!(!s.is_full());
assert_eq!(r.len(), 1);
assert!(!r.is_empty());
assert!(!r.is_full());
r.recv().unwrap();
assert_eq!(s.len(), 0);
assert!(s.is_empty());
assert!(!s.is_full());
assert_eq!(r.len(), 0);
assert!(r.is_empty());
assert!(!r.is_full());
}
#[test]
#[cfg_attr(miri, ignore)] // this test makes timing assumptions, but Miri is so slow it violates them
fn try_recv() {
let (s, r) = unbounded();
scope(|scope| {
scope.spawn(move |_| {
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
thread::sleep(ms(1500));
assert_eq!(r.try_recv(), Ok(7));
thread::sleep(ms(500));
assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected));
});
scope.spawn(move |_| {
thread::sleep(ms(1000));
s.send(7).unwrap();
});
})
.unwrap();
}
#[test]
fn recv() {
let (s, r) = unbounded();
scope(|scope| {
scope.spawn(move |_| {
assert_eq!(r.recv(), Ok(7));
thread::sleep(ms(1000));
assert_eq!(r.recv(), Ok(8));
thread::sleep(ms(1000));
assert_eq!(r.recv(), Ok(9));
assert_eq!(r.recv(), Err(RecvError));
});
scope.spawn(move |_| {
thread::sleep(ms(1500));
s.send(7).unwrap();
s.send(8).unwrap();
s.send(9).unwrap();
});
})
.unwrap();
}
#[test]
fn recv_timeout() {
let (s, r) = unbounded::<i32>();
scope(|scope| {
scope.spawn(move |_| {
assert_eq!(r.recv_timeout(ms(1000)), Err(RecvTimeoutError::Timeout));
assert_eq!(r.recv_timeout(ms(1000)), Ok(7));
assert_eq!(
r.recv_timeout(ms(1000)),
Err(RecvTimeoutError::Disconnected)
);
});
scope.spawn(move |_| {
thread::sleep(ms(1500));
s.send(7).unwrap();
});
})
.unwrap();
}
#[test]
fn try_send() {
#[cfg(miri)]
const COUNT: usize = 50;
#[cfg(not(miri))]
const COUNT: usize = 1000;
let (s, r) = unbounded();
for i in 0..COUNT {
assert_eq!(s.try_send(i), Ok(()));
}
drop(r);
assert_eq!(s.try_send(777), Err(TrySendError::Disconnected(777)));
}
#[test]
fn send() {
#[cfg(miri)]
const COUNT: usize = 50;
#[cfg(not(miri))]
const COUNT: usize = 1000;
let (s, r) = unbounded();
for i in 0..COUNT {
assert_eq!(s.send(i), Ok(()));
}
drop(r);
assert_eq!(s.send(777), Err(SendError(777)));
}
#[test]
fn send_timeout() {
#[cfg(miri)]
const COUNT: usize = 50;
#[cfg(not(miri))]
const COUNT: usize = 1000;
let (s, r) = unbounded();
for i in 0..COUNT {
assert_eq!(s.send_timeout(i, ms(i as u64)), Ok(()));
}
drop(r);
assert_eq!(
s.send_timeout(777, ms(0)),
Err(SendTimeoutError::Disconnected(777))
);
}
#[test]
fn send_after_disconnect() {
let (s, r) = unbounded();
s.send(1).unwrap();
s.send(2).unwrap();
s.send(3).unwrap();
drop(r);
assert_eq!(s.send(4), Err(SendError(4)));
assert_eq!(s.try_send(5), Err(TrySendError::Disconnected(5)));
assert_eq!(
s.send_timeout(6, ms(0)),
Err(SendTimeoutError::Disconnected(6))
);
}
#[test]
fn recv_after_disconnect() {
let (s, r) = unbounded();
s.send(1).unwrap();
s.send(2).unwrap();
s.send(3).unwrap();
drop(s);
assert_eq!(r.recv(), Ok(1));
assert_eq!(r.recv(), Ok(2));
assert_eq!(r.recv(), Ok(3));
assert_eq!(r.recv(), Err(RecvError));
}
#[test]
fn len() {
let (s, r) = unbounded();
assert_eq!(s.len(), 0);
assert_eq!(r.len(), 0);
for i in 0..50 {
s.send(i).unwrap();
assert_eq!(s.len(), i + 1);
}
for i in 0..50 {
r.recv().unwrap();
assert_eq!(r.len(), 50 - i - 1);
}
assert_eq!(s.len(), 0);
assert_eq!(r.len(), 0);
}
#[test]
fn disconnect_wakes_receiver() {
let (s, r) = unbounded::<()>();
scope(|scope| {
scope.spawn(move |_| {
assert_eq!(r.recv(), Err(RecvError));
});
scope.spawn(move |_| {
thread::sleep(ms(1000));
drop(s);
});
})
.unwrap();
}
#[test]
fn spsc() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 100_000;
let (s, r) = unbounded();
scope(|scope| {
scope.spawn(move |_| {
for i in 0..COUNT {
assert_eq!(r.recv(), Ok(i));
}
assert_eq!(r.recv(), Err(RecvError));
});
scope.spawn(move |_| {
for i in 0..COUNT {
s.send(i).unwrap();
}
});
})
.unwrap();
}
#[test]
fn mpmc() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 25_000;
const THREADS: usize = 4;
let (s, r) = unbounded::<usize>();
let v = (0..COUNT).map(|_| AtomicUsize::new(0)).collect::<Vec<_>>();
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
for _ in 0..COUNT {
let n = r.recv().unwrap();
v[n].fetch_add(1, Ordering::SeqCst);
}
});
}
for _ in 0..THREADS {
scope.spawn(|_| {
for i in 0..COUNT {
s.send(i).unwrap();
}
});
}
})
.unwrap();
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
for c in v {
assert_eq!(c.load(Ordering::SeqCst), THREADS);
}
}
#[test]
fn stress_oneshot() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
for _ in 0..COUNT {
let (s, r) = unbounded();
scope(|scope| {
scope.spawn(|_| r.recv().unwrap());
scope.spawn(|_| s.send(0).unwrap());
})
.unwrap();
}
}
#[test]
fn stress_iter() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 100_000;
let (request_s, request_r) = unbounded();
let (response_s, response_r) = unbounded();
scope(|scope| {
scope.spawn(move |_| {
let mut count = 0;
loop {
for x in response_r.try_iter() {
count += x;
if count == COUNT {
return;
}
}
request_s.send(()).unwrap();
}
});
for _ in request_r.iter() {
if response_s.send(1).is_err() {
break;
}
}
})
.unwrap();
}
#[test]
fn stress_timeout_two_threads() {
const COUNT: usize = 100;
let (s, r) = unbounded();
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
if i % 2 == 0 {
thread::sleep(ms(50));
}
s.send(i).unwrap();
}
});
scope.spawn(|_| {
for i in 0..COUNT {
if i % 2 == 0 {
thread::sleep(ms(50));
}
loop {
if let Ok(x) = r.recv_timeout(ms(10)) {
assert_eq!(x, i);
break;
}
}
}
});
})
.unwrap();
}
#[test]
fn drops() {
#[cfg(miri)]
const RUNS: usize = 20;
#[cfg(not(miri))]
const RUNS: usize = 100;
#[cfg(miri)]
const STEPS: usize = 100;
#[cfg(not(miri))]
const STEPS: usize = 10_000;
static DROPS: AtomicUsize = AtomicUsize::new(0);
#[derive(Debug, PartialEq)]
struct DropCounter;
impl Drop for DropCounter {
fn drop(&mut self) {
DROPS.fetch_add(1, Ordering::SeqCst);
}
}
let mut rng = thread_rng();
for _ in 0..RUNS {
let steps = rng.gen_range(0..STEPS);
let additional = rng.gen_range(0..STEPS / 10);
DROPS.store(0, Ordering::SeqCst);
let (s, r) = unbounded::<DropCounter>();
scope(|scope| {
scope.spawn(|_| {
for _ in 0..steps {
r.recv().unwrap();
}
});
scope.spawn(|_| {
for _ in 0..steps {
s.send(DropCounter).unwrap();
}
});
})
.unwrap();
for _ in 0..additional {
s.try_send(DropCounter).unwrap();
}
assert_eq!(DROPS.load(Ordering::SeqCst), steps);
drop(s);
drop(r);
assert_eq!(DROPS.load(Ordering::SeqCst), steps + additional);
}
}
#[test]
fn linearizable() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 25_000;
const THREADS: usize = 4;
let (s, r) = unbounded();
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
for _ in 0..COUNT {
s.send(0).unwrap();
r.try_recv().unwrap();
}
});
}
})
.unwrap();
}
#[test]
fn fairness() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s1, r1) = unbounded::<()>();
let (s2, r2) = unbounded::<()>();
for _ in 0..COUNT {
s1.send(()).unwrap();
s2.send(()).unwrap();
}
let mut hits = [0usize; 2];
for _ in 0..COUNT {
select! {
recv(r1) -> _ => hits[0] += 1,
recv(r2) -> _ => hits[1] += 1,
}
}
assert!(hits.iter().all(|x| *x >= COUNT / hits.len() / 2));
}
#[test]
fn fairness_duplicates() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s, r) = unbounded();
for _ in 0..COUNT {
s.send(()).unwrap();
}
let mut hits = [0usize; 5];
for _ in 0..COUNT {
select! {
recv(r) -> _ => hits[0] += 1,
recv(r) -> _ => hits[1] += 1,
recv(r) -> _ => hits[2] += 1,
recv(r) -> _ => hits[3] += 1,
recv(r) -> _ => hits[4] += 1,
}
}
assert!(hits.iter().all(|x| *x >= COUNT / hits.len() / 2));
}
#[test]
fn recv_in_send() {
let (s, r) = unbounded();
s.send(()).unwrap();
select! {
send(s, assert_eq!(r.recv(), Ok(()))) -> _ => {}
}
}
#[test]
fn channel_through_channel() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 1000;
type T = Box<dyn Any + Send>;
let (s, r) = unbounded::<T>();
scope(|scope| {
scope.spawn(move |_| {
let mut s = s;
for _ in 0..COUNT {
let (new_s, new_r) = unbounded();
let new_r: T = Box::new(Some(new_r));
s.send(new_r).unwrap();
s = new_s;
}
});
scope.spawn(move |_| {
let mut r = r;
for _ in 0..COUNT {
r = r
.recv()
.unwrap()
.downcast_mut::<Option<Receiver<T>>>()
.unwrap()
.take()
.unwrap()
}
});
})
.unwrap();
}