Revision control
Copy as Markdown
Other Tools
//! Tests for the after channel flavor.
#![cfg(not(miri))] // TODO: many assertions failed due to Miri is slow
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering;
use std::thread;
use std::time::{Duration, Instant};
use crossbeam_channel::{after, select, Select, TryRecvError};
use crossbeam_utils::thread::scope;
fn ms(ms: u64) -> Duration {
Duration::from_millis(ms)
}
#[test]
fn fire() {
let start = Instant::now();
let r = after(ms(50));
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
thread::sleep(ms(100));
let fired = r.try_recv().unwrap();
assert!(start < fired);
assert!(fired - start >= ms(50));
let now = Instant::now();
assert!(fired < now);
assert!(now - fired >= ms(50));
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
select! {
recv(r) -> _ => panic!(),
default => {}
}
select! {
recv(r) -> _ => panic!(),
recv(after(ms(200))) -> _ => {}
}
}
#[test]
fn capacity() {
const COUNT: usize = 10;
for i in 0..COUNT {
let r = after(ms(i as u64));
assert_eq!(r.capacity(), Some(1));
}
}
#[test]
fn len_empty_full() {
let r = after(ms(50));
assert_eq!(r.len(), 0);
assert!(r.is_empty());
assert!(!r.is_full());
thread::sleep(ms(100));
assert_eq!(r.len(), 1);
assert!(!r.is_empty());
assert!(r.is_full());
r.try_recv().unwrap();
assert_eq!(r.len(), 0);
assert!(r.is_empty());
assert!(!r.is_full());
}
#[test]
fn try_recv() {
let r = after(ms(200));
assert!(r.try_recv().is_err());
thread::sleep(ms(100));
assert!(r.try_recv().is_err());
thread::sleep(ms(200));
assert!(r.try_recv().is_ok());
assert!(r.try_recv().is_err());
thread::sleep(ms(200));
assert!(r.try_recv().is_err());
}
#[test]
fn recv() {
let start = Instant::now();
let r = after(ms(50));
let fired = r.recv().unwrap();
assert!(start < fired);
assert!(fired - start >= ms(50));
let now = Instant::now();
assert!(fired < now);
assert!(now - fired < fired - start);
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
}
#[test]
fn recv_timeout() {
let start = Instant::now();
let r = after(ms(200));
assert!(r.recv_timeout(ms(100)).is_err());
let now = Instant::now();
assert!(now - start >= ms(100));
assert!(now - start <= ms(150));
let fired = r.recv_timeout(ms(200)).unwrap();
assert!(fired - start >= ms(200));
assert!(fired - start <= ms(250));
assert!(r.recv_timeout(ms(200)).is_err());
let now = Instant::now();
assert!(now - start >= ms(400));
assert!(now - start <= ms(450));
assert_eq!(r.try_recv(), Err(TryRecvError::Empty));
}
#[test]
fn recv_two() {
let r1 = after(ms(50));
let r2 = after(ms(50));
scope(|scope| {
scope.spawn(|_| {
select! {
recv(r1) -> _ => {}
recv(r2) -> _ => {}
}
});
scope.spawn(|_| {
select! {
recv(r1) -> _ => {}
recv(r2) -> _ => {}
}
});
})
.unwrap();
}
#[test]
fn recv_race() {
select! {
recv(after(ms(50))) -> _ => {}
recv(after(ms(100))) -> _ => panic!(),
}
select! {
recv(after(ms(100))) -> _ => panic!(),
recv(after(ms(50))) -> _ => {}
}
}
#[test]
fn stress_default() {
const COUNT: usize = 10;
for _ in 0..COUNT {
select! {
recv(after(ms(0))) -> _ => {}
default => panic!(),
}
}
for _ in 0..COUNT {
select! {
recv(after(ms(100))) -> _ => panic!(),
default => {}
}
}
}
#[test]
fn select() {
const THREADS: usize = 4;
const COUNT: usize = 1000;
const TIMEOUT_MS: u64 = 100;
let v = (0..COUNT)
.map(|i| after(ms(i as u64 / TIMEOUT_MS / 2)))
.collect::<Vec<_>>();
let hits = AtomicUsize::new(0);
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
let v: Vec<&_> = v.iter().collect();
loop {
let timeout = after(ms(TIMEOUT_MS));
let mut sel = Select::new();
for r in &v {
sel.recv(r);
}
let oper_timeout = sel.recv(&timeout);
let oper = sel.select();
match oper.index() {
i if i == oper_timeout => {
oper.recv(&timeout).unwrap();
break;
}
i => {
oper.recv(v[i]).unwrap();
hits.fetch_add(1, Ordering::SeqCst);
}
}
}
});
}
})
.unwrap();
assert_eq!(hits.load(Ordering::SeqCst), COUNT);
}
#[test]
fn ready() {
const THREADS: usize = 4;
const COUNT: usize = 1000;
const TIMEOUT_MS: u64 = 100;
let v = (0..COUNT)
.map(|i| after(ms(i as u64 / TIMEOUT_MS / 2)))
.collect::<Vec<_>>();
let hits = AtomicUsize::new(0);
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
let v: Vec<&_> = v.iter().collect();
loop {
let timeout = after(ms(TIMEOUT_MS));
let mut sel = Select::new();
for r in &v {
sel.recv(r);
}
let oper_timeout = sel.recv(&timeout);
loop {
let i = sel.ready();
if i == oper_timeout {
timeout.try_recv().unwrap();
return;
} else if v[i].try_recv().is_ok() {
hits.fetch_add(1, Ordering::SeqCst);
break;
}
}
}
});
}
})
.unwrap();
assert_eq!(hits.load(Ordering::SeqCst), COUNT);
}
#[test]
fn stress_clone() {
const RUNS: usize = 1000;
const THREADS: usize = 10;
const COUNT: usize = 50;
for i in 0..RUNS {
let r = after(ms(i as u64));
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
let r = r.clone();
let _ = r.try_recv();
for _ in 0..COUNT {
drop(r.clone());
thread::yield_now();
}
});
}
})
.unwrap();
}
}
#[test]
fn fairness() {
const COUNT: usize = 1000;
for &dur in &[0, 1] {
let mut hits = [0usize; 2];
for _ in 0..COUNT {
select! {
recv(after(ms(dur))) -> _ => hits[0] += 1,
recv(after(ms(dur))) -> _ => hits[1] += 1,
}
}
assert!(hits.iter().all(|x| *x >= COUNT / hits.len() / 2));
}
}
#[test]
fn fairness_duplicates() {
const COUNT: usize = 1000;
for &dur in &[0, 1] {
let mut hits = [0usize; 5];
for _ in 0..COUNT {
let r = after(ms(dur));
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));
}
}