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//! Tests for channel readiness using the `Select` struct.
#![allow(clippy::drop_copy)]
use std::any::Any;
use std::cell::Cell;
use std::thread;
use std::time::{Duration, Instant};
use crossbeam_channel::{after, bounded, tick, unbounded};
use crossbeam_channel::{Receiver, Select, TryRecvError, TrySendError};
use crossbeam_utils::thread::scope;
fn ms(ms: u64) -> Duration {
Duration::from_millis(ms)
}
#[test]
fn smoke1() {
let (s1, r1) = unbounded::<usize>();
let (s2, r2) = unbounded::<usize>();
s1.send(1).unwrap();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
assert_eq!(sel.ready(), 0);
assert_eq!(r1.try_recv(), Ok(1));
s2.send(2).unwrap();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
assert_eq!(sel.ready(), 1);
assert_eq!(r2.try_recv(), Ok(2));
}
#[test]
fn smoke2() {
let (_s1, r1) = unbounded::<i32>();
let (_s2, r2) = unbounded::<i32>();
let (_s3, r3) = unbounded::<i32>();
let (_s4, r4) = unbounded::<i32>();
let (s5, r5) = unbounded::<i32>();
s5.send(5).unwrap();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
sel.recv(&r3);
sel.recv(&r4);
sel.recv(&r5);
assert_eq!(sel.ready(), 4);
assert_eq!(r5.try_recv(), Ok(5));
}
#[test]
fn disconnected() {
let (s1, r1) = unbounded::<i32>();
let (s2, r2) = unbounded::<i32>();
scope(|scope| {
scope.spawn(|_| {
drop(s1);
thread::sleep(ms(500));
s2.send(5).unwrap();
});
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready_timeout(ms(1000)) {
Ok(0) => assert_eq!(r1.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
r2.recv().unwrap();
})
.unwrap();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready_timeout(ms(1000)) {
Ok(0) => assert_eq!(r1.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
scope(|scope| {
scope.spawn(|_| {
thread::sleep(ms(500));
drop(s2);
});
let mut sel = Select::new();
sel.recv(&r2);
match sel.ready_timeout(ms(1000)) {
Ok(0) => assert_eq!(r2.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
})
.unwrap();
}
#[test]
fn default() {
let (s1, r1) = unbounded::<i32>();
let (s2, r2) = unbounded::<i32>();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
assert!(sel.try_ready().is_err());
drop(s1);
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.try_ready() {
Ok(0) => assert!(r1.try_recv().is_err()),
_ => panic!(),
}
s2.send(2).unwrap();
let mut sel = Select::new();
sel.recv(&r2);
match sel.try_ready() {
Ok(0) => assert_eq!(r2.try_recv(), Ok(2)),
_ => panic!(),
}
let mut sel = Select::new();
sel.recv(&r2);
assert!(sel.try_ready().is_err());
let mut sel = Select::new();
assert!(sel.try_ready().is_err());
}
#[test]
fn timeout() {
let (_s1, r1) = unbounded::<i32>();
let (s2, r2) = unbounded::<i32>();
scope(|scope| {
scope.spawn(|_| {
thread::sleep(ms(1500));
s2.send(2).unwrap();
});
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
assert!(sel.ready_timeout(ms(1000)).is_err());
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready_timeout(ms(1000)) {
Ok(1) => assert_eq!(r2.try_recv(), Ok(2)),
_ => panic!(),
}
})
.unwrap();
scope(|scope| {
let (s, r) = unbounded::<i32>();
scope.spawn(move |_| {
thread::sleep(ms(500));
drop(s);
});
let mut sel = Select::new();
assert!(sel.ready_timeout(ms(1000)).is_err());
let mut sel = Select::new();
sel.recv(&r);
match sel.try_ready() {
Ok(0) => assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
})
.unwrap();
}
#[test]
fn default_when_disconnected() {
let (_, r) = unbounded::<i32>();
let mut sel = Select::new();
sel.recv(&r);
match sel.try_ready() {
Ok(0) => assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
let (_, r) = unbounded::<i32>();
let mut sel = Select::new();
sel.recv(&r);
match sel.ready_timeout(ms(1000)) {
Ok(0) => assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
let (s, _) = bounded::<i32>(0);
let mut sel = Select::new();
sel.send(&s);
match sel.try_ready() {
Ok(0) => assert_eq!(s.try_send(0), Err(TrySendError::Disconnected(0))),
_ => panic!(),
}
let (s, _) = bounded::<i32>(0);
let mut sel = Select::new();
sel.send(&s);
match sel.ready_timeout(ms(1000)) {
Ok(0) => assert_eq!(s.try_send(0), Err(TrySendError::Disconnected(0))),
_ => panic!(),
}
}
#[test]
fn default_only() {
let start = Instant::now();
let mut sel = Select::new();
assert!(sel.try_ready().is_err());
let now = Instant::now();
assert!(now - start <= ms(50));
let start = Instant::now();
let mut sel = Select::new();
assert!(sel.ready_timeout(ms(500)).is_err());
let now = Instant::now();
assert!(now - start >= ms(450));
assert!(now - start <= ms(550));
}
#[test]
fn unblocks() {
let (s1, r1) = bounded::<i32>(0);
let (s2, r2) = bounded::<i32>(0);
scope(|scope| {
scope.spawn(|_| {
thread::sleep(ms(500));
s2.send(2).unwrap();
});
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready_timeout(ms(1000)) {
Ok(1) => assert_eq!(r2.try_recv(), Ok(2)),
_ => panic!(),
}
})
.unwrap();
scope(|scope| {
scope.spawn(|_| {
thread::sleep(ms(500));
assert_eq!(r1.recv().unwrap(), 1);
});
let mut sel = Select::new();
let oper1 = sel.send(&s1);
let oper2 = sel.send(&s2);
let oper = sel.select_timeout(ms(1000));
match oper {
Err(_) => panic!(),
Ok(oper) => match oper.index() {
i if i == oper1 => oper.send(&s1, 1).unwrap(),
i if i == oper2 => panic!(),
_ => unreachable!(),
},
}
})
.unwrap();
}
#[test]
fn both_ready() {
let (s1, r1) = bounded(0);
let (s2, r2) = bounded(0);
scope(|scope| {
scope.spawn(|_| {
thread::sleep(ms(500));
s1.send(1).unwrap();
assert_eq!(r2.recv().unwrap(), 2);
});
for _ in 0..2 {
let mut sel = Select::new();
sel.recv(&r1);
sel.send(&s2);
match sel.ready() {
0 => assert_eq!(r1.try_recv(), Ok(1)),
1 => s2.try_send(2).unwrap(),
_ => panic!(),
}
}
})
.unwrap();
}
#[test]
fn cloning1() {
scope(|scope| {
let (s1, r1) = unbounded::<i32>();
let (_s2, r2) = unbounded::<i32>();
let (s3, r3) = unbounded::<()>();
scope.spawn(move |_| {
r3.recv().unwrap();
drop(s1.clone());
assert!(r3.try_recv().is_err());
s1.send(1).unwrap();
r3.recv().unwrap();
});
s3.send(()).unwrap();
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready() {
0 => drop(r1.try_recv()),
1 => drop(r2.try_recv()),
_ => panic!(),
}
s3.send(()).unwrap();
})
.unwrap();
}
#[test]
fn cloning2() {
let (s1, r1) = unbounded::<()>();
let (s2, r2) = unbounded::<()>();
let (_s3, _r3) = unbounded::<()>();
scope(|scope| {
scope.spawn(move |_| {
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready() {
0 => panic!(),
1 => drop(r2.try_recv()),
_ => panic!(),
}
});
thread::sleep(ms(500));
drop(s1.clone());
s2.send(()).unwrap();
})
.unwrap();
}
#[test]
fn preflight1() {
let (s, r) = unbounded();
s.send(()).unwrap();
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => drop(r.try_recv()),
_ => panic!(),
}
}
#[test]
fn preflight2() {
let (s, r) = unbounded();
drop(s.clone());
s.send(()).unwrap();
drop(s);
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => assert_eq!(r.try_recv(), Ok(())),
_ => panic!(),
}
assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected));
}
#[test]
fn preflight3() {
let (s, r) = unbounded();
drop(s.clone());
s.send(()).unwrap();
drop(s);
r.recv().unwrap();
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => assert_eq!(r.try_recv(), Err(TryRecvError::Disconnected)),
_ => panic!(),
}
}
#[test]
fn duplicate_operations() {
let (s, r) = unbounded::<i32>();
let hit = vec![Cell::new(false); 4];
while hit.iter().map(|h| h.get()).any(|hit| !hit) {
let mut sel = Select::new();
sel.recv(&r);
sel.recv(&r);
sel.send(&s);
sel.send(&s);
match sel.ready() {
0 => {
assert!(r.try_recv().is_ok());
hit[0].set(true);
}
1 => {
assert!(r.try_recv().is_ok());
hit[1].set(true);
}
2 => {
assert!(s.try_send(0).is_ok());
hit[2].set(true);
}
3 => {
assert!(s.try_send(0).is_ok());
hit[3].set(true);
}
_ => panic!(),
}
}
}
#[test]
fn nesting() {
let (s, r) = unbounded::<i32>();
let mut sel = Select::new();
sel.send(&s);
match sel.ready() {
0 => {
assert!(s.try_send(0).is_ok());
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => {
assert_eq!(r.try_recv(), Ok(0));
let mut sel = Select::new();
sel.send(&s);
match sel.ready() {
0 => {
assert!(s.try_send(1).is_ok());
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => {
assert_eq!(r.try_recv(), Ok(1));
}
_ => panic!(),
}
}
_ => panic!(),
}
}
_ => panic!(),
}
}
_ => panic!(),
}
}
#[test]
fn stress_recv() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s1, r1) = unbounded();
let (s2, r2) = bounded(5);
let (s3, r3) = bounded(0);
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
s1.send(i).unwrap();
r3.recv().unwrap();
s2.send(i).unwrap();
r3.recv().unwrap();
}
});
for i in 0..COUNT {
for _ in 0..2 {
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
match sel.ready() {
0 => assert_eq!(r1.try_recv(), Ok(i)),
1 => assert_eq!(r2.try_recv(), Ok(i)),
_ => panic!(),
}
s3.send(()).unwrap();
}
}
})
.unwrap();
}
#[test]
fn stress_send() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s1, r1) = bounded(0);
let (s2, r2) = bounded(0);
let (s3, r3) = bounded(100);
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
assert_eq!(r1.recv().unwrap(), i);
assert_eq!(r2.recv().unwrap(), i);
r3.recv().unwrap();
}
});
for i in 0..COUNT {
for _ in 0..2 {
let mut sel = Select::new();
sel.send(&s1);
sel.send(&s2);
match sel.ready() {
0 => assert!(s1.try_send(i).is_ok()),
1 => assert!(s2.try_send(i).is_ok()),
_ => panic!(),
}
}
s3.send(()).unwrap();
}
})
.unwrap();
}
#[test]
fn stress_mixed() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s1, r1) = bounded(0);
let (s2, r2) = bounded(0);
let (s3, r3) = bounded(100);
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
s1.send(i).unwrap();
assert_eq!(r2.recv().unwrap(), i);
r3.recv().unwrap();
}
});
for i in 0..COUNT {
for _ in 0..2 {
let mut sel = Select::new();
sel.recv(&r1);
sel.send(&s2);
match sel.ready() {
0 => assert_eq!(r1.try_recv(), Ok(i)),
1 => assert!(s2.try_send(i).is_ok()),
_ => panic!(),
}
}
s3.send(()).unwrap();
}
})
.unwrap();
}
#[test]
fn stress_timeout_two_threads() {
const COUNT: usize = 20;
let (s, r) = bounded(2);
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
if i % 2 == 0 {
thread::sleep(ms(500));
}
loop {
let mut sel = Select::new();
sel.send(&s);
match sel.ready_timeout(ms(100)) {
Err(_) => {}
Ok(0) => {
assert!(s.try_send(i).is_ok());
break;
}
Ok(_) => panic!(),
}
}
}
});
scope.spawn(|_| {
for i in 0..COUNT {
if i % 2 == 0 {
thread::sleep(ms(500));
}
loop {
let mut sel = Select::new();
sel.recv(&r);
match sel.ready_timeout(ms(100)) {
Err(_) => {}
Ok(0) => {
assert_eq!(r.try_recv(), Ok(i));
break;
}
Ok(_) => panic!(),
}
}
}
});
})
.unwrap();
}
#[test]
fn send_recv_same_channel() {
let (s, r) = bounded::<i32>(0);
let mut sel = Select::new();
sel.send(&s);
sel.recv(&r);
assert!(sel.ready_timeout(ms(100)).is_err());
let (s, r) = unbounded::<i32>();
let mut sel = Select::new();
sel.send(&s);
sel.recv(&r);
match sel.ready_timeout(ms(100)) {
Err(_) => panic!(),
Ok(0) => assert!(s.try_send(0).is_ok()),
Ok(_) => panic!(),
}
}
#[test]
fn channel_through_channel() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 1000;
type T = Box<dyn Any + Send>;
for cap in 1..4 {
let (s, r) = bounded::<T>(cap);
scope(|scope| {
scope.spawn(move |_| {
let mut s = s;
for _ in 0..COUNT {
let (new_s, new_r) = bounded(cap);
let new_r: T = Box::new(Some(new_r));
{
let mut sel = Select::new();
sel.send(&s);
match sel.ready() {
0 => assert!(s.try_send(new_r).is_ok()),
_ => panic!(),
}
}
s = new_s;
}
});
scope.spawn(move |_| {
let mut r = r;
for _ in 0..COUNT {
let new = {
let mut sel = Select::new();
sel.recv(&r);
match sel.ready() {
0 => r
.try_recv()
.unwrap()
.downcast_mut::<Option<Receiver<T>>>()
.unwrap()
.take()
.unwrap(),
_ => panic!(),
}
};
r = new;
}
});
})
.unwrap();
}
}
#[test]
fn fairness1() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 10_000;
let (s1, r1) = bounded::<()>(COUNT);
let (s2, r2) = unbounded::<()>();
for _ in 0..COUNT {
s1.send(()).unwrap();
s2.send(()).unwrap();
}
let hits = vec![Cell::new(0usize); 4];
for _ in 0..COUNT {
let after = after(ms(0));
let tick = tick(ms(0));
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
sel.recv(&after);
sel.recv(&tick);
match sel.ready() {
0 => {
r1.try_recv().unwrap();
hits[0].set(hits[0].get() + 1);
}
1 => {
r2.try_recv().unwrap();
hits[1].set(hits[1].get() + 1);
}
2 => {
after.try_recv().unwrap();
hits[2].set(hits[2].get() + 1);
}
3 => {
tick.try_recv().unwrap();
hits[3].set(hits[3].get() + 1);
}
_ => panic!(),
}
}
assert!(hits.iter().all(|x| x.get() >= COUNT / hits.len() / 2));
}
#[test]
fn fairness2() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 100_000;
let (s1, r1) = unbounded::<()>();
let (s2, r2) = bounded::<()>(1);
let (s3, r3) = bounded::<()>(0);
scope(|scope| {
scope.spawn(|_| {
for _ in 0..COUNT {
let mut sel = Select::new();
let mut oper1 = None;
let mut oper2 = None;
if s1.is_empty() {
oper1 = Some(sel.send(&s1));
}
if s2.is_empty() {
oper2 = Some(sel.send(&s2));
}
let oper3 = sel.send(&s3);
let oper = sel.select();
match oper.index() {
i if Some(i) == oper1 => assert!(oper.send(&s1, ()).is_ok()),
i if Some(i) == oper2 => assert!(oper.send(&s2, ()).is_ok()),
i if i == oper3 => assert!(oper.send(&s3, ()).is_ok()),
_ => unreachable!(),
}
}
});
let hits = vec![Cell::new(0usize); 3];
for _ in 0..COUNT {
let mut sel = Select::new();
sel.recv(&r1);
sel.recv(&r2);
sel.recv(&r3);
loop {
match sel.ready() {
0 => {
if r1.try_recv().is_ok() {
hits[0].set(hits[0].get() + 1);
break;
}
}
1 => {
if r2.try_recv().is_ok() {
hits[1].set(hits[1].get() + 1);
break;
}
}
2 => {
if r3.try_recv().is_ok() {
hits[2].set(hits[2].get() + 1);
break;
}
}
_ => unreachable!(),
}
}
}
assert!(hits.iter().all(|x| x.get() > 0));
})
.unwrap();
}