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use std::sync::atomic::{AtomicUsize, Ordering};
use crossbeam_queue::SegQueue;
use crossbeam_utils::thread::scope;
use rand::{thread_rng, Rng};
#[test]
fn smoke() {
let q = SegQueue::new();
q.push(7);
assert_eq!(q.pop(), Some(7));
q.push(8);
assert_eq!(q.pop(), Some(8));
assert!(q.pop().is_none());
}
#[test]
fn len_empty_full() {
let q = SegQueue::new();
assert_eq!(q.len(), 0);
assert!(q.is_empty());
q.push(());
assert_eq!(q.len(), 1);
assert!(!q.is_empty());
q.pop().unwrap();
assert_eq!(q.len(), 0);
assert!(q.is_empty());
}
#[test]
fn len() {
let q = SegQueue::new();
assert_eq!(q.len(), 0);
for i in 0..50 {
q.push(i);
assert_eq!(q.len(), i + 1);
}
for i in 0..50 {
q.pop().unwrap();
assert_eq!(q.len(), 50 - i - 1);
}
assert_eq!(q.len(), 0);
}
#[test]
fn spsc() {
#[cfg(miri)]
const COUNT: usize = 100;
#[cfg(not(miri))]
const COUNT: usize = 100_000;
let q = SegQueue::new();
scope(|scope| {
scope.spawn(|_| {
for i in 0..COUNT {
loop {
if let Some(x) = q.pop() {
assert_eq!(x, i);
break;
}
}
}
assert!(q.pop().is_none());
});
scope.spawn(|_| {
for i in 0..COUNT {
q.push(i);
}
});
})
.unwrap();
}
#[test]
fn mpmc() {
#[cfg(miri)]
const COUNT: usize = 50;
#[cfg(not(miri))]
const COUNT: usize = 25_000;
const THREADS: usize = 4;
let q = SegQueue::<usize>::new();
let v = (0..COUNT).map(|_| AtomicUsize::new(0)).collect::<Vec<_>>();
scope(|scope| {
for _ in 0..THREADS {
scope.spawn(|_| {
for _ in 0..COUNT {
let n = loop {
if let Some(x) = q.pop() {
break x;
}
};
v[n].fetch_add(1, Ordering::SeqCst);
}
});
}
for _ in 0..THREADS {
scope.spawn(|_| {
for i in 0..COUNT {
q.push(i);
}
});
}
})
.unwrap();
for c in v {
assert_eq!(c.load(Ordering::SeqCst), THREADS);
}
}
#[test]
fn drops() {
let runs: usize = if cfg!(miri) { 5 } else { 100 };
let steps: usize = if cfg!(miri) { 50 } else { 10_000 };
let additional: usize = if cfg!(miri) { 100 } else { 1_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..additional);
DROPS.store(0, Ordering::SeqCst);
let q = SegQueue::new();
scope(|scope| {
scope.spawn(|_| {
for _ in 0..steps {
while q.pop().is_none() {}
}
});
scope.spawn(|_| {
for _ in 0..steps {
q.push(DropCounter);
}
});
})
.unwrap();
for _ in 0..additional {
q.push(DropCounter);
}
assert_eq!(DROPS.load(Ordering::SeqCst), steps);
drop(q);
assert_eq!(DROPS.load(Ordering::SeqCst), steps + additional);
}
}
#[test]
fn into_iter() {
let q = SegQueue::new();
for i in 0..100 {
q.push(i);
}
for (i, j) in q.into_iter().enumerate() {
assert_eq!(i, j);
}
}
#[test]
fn into_iter_drop() {
let q = SegQueue::new();
for i in 0..100 {
q.push(i);
}
for (i, j) in q.into_iter().enumerate().take(50) {
assert_eq!(i, j);
}
}