Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

4 files changed, 1303 insertions, 0 deletions

diff --git a/vendor/crossbeam-deque/tests/fifo.rs b/vendor/crossbeam-deque/tests/fifo.rs
new file mode 100644
index 0000000..f98737b
--- /dev/null
+++ b/vendor/crossbeam-deque/tests/fifo.rs
@@ -0,0 +1,357 @@
+use std::sync::atomic::Ordering::SeqCst;
+use std::sync::atomic::{AtomicBool, AtomicUsize};
+use std::sync::{Arc, Mutex};
+
+use crossbeam_deque::Steal::{Empty, Success};
+use crossbeam_deque::Worker;
+use crossbeam_utils::thread::scope;
+use rand::Rng;
+
+#[test]
+fn smoke() {
+    let w = Worker::new_fifo();
+    let s = w.stealer();
+    assert_eq!(w.pop(), None);
+    assert_eq!(s.steal(), Empty);
+
+    w.push(1);
+    assert_eq!(w.pop(), Some(1));
+    assert_eq!(w.pop(), None);
+    assert_eq!(s.steal(), Empty);
+
+    w.push(2);
+    assert_eq!(s.steal(), Success(2));
+    assert_eq!(s.steal(), Empty);
+    assert_eq!(w.pop(), None);
+
+    w.push(3);
+    w.push(4);
+    w.push(5);
+    assert_eq!(s.steal(), Success(3));
+    assert_eq!(s.steal(), Success(4));
+    assert_eq!(s.steal(), Success(5));
+    assert_eq!(s.steal(), Empty);
+
+    w.push(6);
+    w.push(7);
+    w.push(8);
+    w.push(9);
+    assert_eq!(w.pop(), Some(6));
+    assert_eq!(s.steal(), Success(7));
+    assert_eq!(w.pop(), Some(8));
+    assert_eq!(w.pop(), Some(9));
+    assert_eq!(w.pop(), None);
+}
+
+#[test]
+fn is_empty() {
+    let w = Worker::new_fifo();
+    let s = w.stealer();
+
+    assert!(w.is_empty());
+    w.push(1);
+    assert!(!w.is_empty());
+    w.push(2);
+    assert!(!w.is_empty());
+    let _ = w.pop();
+    assert!(!w.is_empty());
+    let _ = w.pop();
+    assert!(w.is_empty());
+
+    assert!(s.is_empty());
+    w.push(1);
+    assert!(!s.is_empty());
+    w.push(2);
+    assert!(!s.is_empty());
+    let _ = s.steal();
+    assert!(!s.is_empty());
+    let _ = s.steal();
+    assert!(s.is_empty());
+}
+
+#[test]
+fn spsc() {
+    #[cfg(miri)]
+    const STEPS: usize = 500;
+    #[cfg(not(miri))]
+    const STEPS: usize = 50_000;
+
+    let w = Worker::new_fifo();
+    let s = w.stealer();
+
+    scope(|scope| {
+        scope.spawn(|_| {
+            for i in 0..STEPS {
+                loop {
+                    if let Success(v) = s.steal() {
+                        assert_eq!(i, v);
+                        break;
+                    }
+                }
+            }
+
+            assert_eq!(s.steal(), Empty);
+        });
+
+        for i in 0..STEPS {
+            w.push(i);
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn stampede() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_fifo();
+
+    for i in 0..COUNT {
+        w.push(Box::new(i + 1));
+    }
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let remaining = remaining.clone();
+
+            scope.spawn(move |_| {
+                let mut last = 0;
+                while remaining.load(SeqCst) > 0 {
+                    if let Success(x) = s.steal() {
+                        assert!(last < *x);
+                        last = *x;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut last = 0;
+        while remaining.load(SeqCst) > 0 {
+            if let Some(x) = w.pop() {
+                assert!(last < *x);
+                last = *x;
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn stress() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_fifo();
+    let done = Arc::new(AtomicBool::new(false));
+    let hits = Arc::new(AtomicUsize::new(0));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let done = done.clone();
+            let hits = hits.clone();
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = s.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut expected = 0;
+        while expected < COUNT {
+            if rng.gen_range(0..3) == 0 {
+                while w.pop().is_some() {
+                    hits.fetch_add(1, SeqCst);
+                }
+            } else {
+                w.push(expected);
+                expected += 1;
+            }
+        }
+
+        while hits.load(SeqCst) < COUNT {
+            while w.pop().is_some() {
+                hits.fetch_add(1, SeqCst);
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[cfg_attr(miri, ignore)] // Miri is too slow
+#[test]
+fn no_starvation() {
+    const THREADS: usize = 8;
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_fifo();
+    let done = Arc::new(AtomicBool::new(false));
+    let mut all_hits = Vec::new();
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let done = done.clone();
+            let hits = Arc::new(AtomicUsize::new(0));
+            all_hits.push(hits.clone());
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = s.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut my_hits = 0;
+        loop {
+            for i in 0..rng.gen_range(0..COUNT) {
+                if rng.gen_range(0..3) == 0 && my_hits == 0 {
+                    while w.pop().is_some() {
+                        my_hits += 1;
+                    }
+                } else {
+                    w.push(i);
+                }
+            }
+
+            if my_hits > 0 && all_hits.iter().all(|h| h.load(SeqCst) > 0) {
+                break;
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[test]
+fn destructors() {
+    #[cfg(miri)]
+    const THREADS: usize = 2;
+    #[cfg(not(miri))]
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+    #[cfg(miri)]
+    const STEPS: usize = 100;
+    #[cfg(not(miri))]
+    const STEPS: usize = 1000;
+
+    struct Elem(usize, Arc<Mutex<Vec<usize>>>);
+
+    impl Drop for Elem {
+        fn drop(&mut self) {
+            self.1.lock().unwrap().push(self.0);
+        }
+    }
+
+    let w = Worker::new_fifo();
+    let dropped = Arc::new(Mutex::new(Vec::new()));
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    for i in 0..COUNT {
+        w.push(Elem(i, dropped.clone()));
+    }
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let remaining = remaining.clone();
+            let s = w.stealer();
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+                let mut cnt = 0;
+
+                while cnt < STEPS {
+                    if let Success(_) = s.steal() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        for _ in 0..STEPS {
+            if w.pop().is_some() {
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+
+    let rem = remaining.load(SeqCst);
+    assert!(rem > 0);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), COUNT - rem);
+        v.clear();
+    }
+
+    drop(w);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), rem);
+        v.sort_unstable();
+        for pair in v.windows(2) {
+            assert_eq!(pair[0] + 1, pair[1]);
+        }
+    }
+}
diff --git a/vendor/crossbeam-deque/tests/injector.rs b/vendor/crossbeam-deque/tests/injector.rs
new file mode 100644
index 0000000..f706a8d
--- /dev/null
+++ b/vendor/crossbeam-deque/tests/injector.rs
@@ -0,0 +1,375 @@
+use std::sync::atomic::Ordering::SeqCst;
+use std::sync::atomic::{AtomicBool, AtomicUsize};
+use std::sync::{Arc, Mutex};
+
+use crossbeam_deque::Steal::{Empty, Success};
+use crossbeam_deque::{Injector, Worker};
+use crossbeam_utils::thread::scope;
+use rand::Rng;
+
+#[test]
+fn smoke() {
+    let q = Injector::new();
+    assert_eq!(q.steal(), Empty);
+
+    q.push(1);
+    q.push(2);
+    assert_eq!(q.steal(), Success(1));
+    assert_eq!(q.steal(), Success(2));
+    assert_eq!(q.steal(), Empty);
+
+    q.push(3);
+    assert_eq!(q.steal(), Success(3));
+    assert_eq!(q.steal(), Empty);
+}
+
+#[test]
+fn is_empty() {
+    let q = Injector::new();
+    assert!(q.is_empty());
+
+    q.push(1);
+    assert!(!q.is_empty());
+    q.push(2);
+    assert!(!q.is_empty());
+
+    let _ = q.steal();
+    assert!(!q.is_empty());
+    let _ = q.steal();
+    assert!(q.is_empty());
+
+    q.push(3);
+    assert!(!q.is_empty());
+    let _ = q.steal();
+    assert!(q.is_empty());
+}
+
+#[test]
+fn spsc() {
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 100_000;
+
+    let q = Injector::new();
+
+    scope(|scope| {
+        scope.spawn(|_| {
+            for i in 0..COUNT {
+                loop {
+                    if let Success(v) = q.steal() {
+                        assert_eq!(i, v);
+                        break;
+                    }
+                    #[cfg(miri)]
+                    std::hint::spin_loop();
+                }
+            }
+
+            assert_eq!(q.steal(), Empty);
+        });
+
+        for i in 0..COUNT {
+            q.push(i);
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn mpmc() {
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 25_000;
+    const THREADS: usize = 4;
+
+    let q = Injector::new();
+    let v = (0..COUNT).map(|_| AtomicUsize::new(0)).collect::<Vec<_>>();
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            scope.spawn(|_| {
+                for i in 0..COUNT {
+                    q.push(i);
+                }
+            });
+        }
+
+        for _ in 0..THREADS {
+            scope.spawn(|_| {
+                for _ in 0..COUNT {
+                    loop {
+                        if let Success(n) = q.steal() {
+                            v[n].fetch_add(1, SeqCst);
+                            break;
+                        }
+                        #[cfg(miri)]
+                        std::hint::spin_loop();
+                    }
+                }
+            });
+        }
+    })
+    .unwrap();
+
+    for c in v {
+        assert_eq!(c.load(SeqCst), THREADS);
+    }
+}
+
+#[test]
+fn stampede() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let q = Injector::new();
+
+    for i in 0..COUNT {
+        q.push(Box::new(i + 1));
+    }
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let remaining = remaining.clone();
+            let q = &q;
+
+            scope.spawn(move |_| {
+                let mut last = 0;
+                while remaining.load(SeqCst) > 0 {
+                    if let Success(x) = q.steal() {
+                        assert!(last < *x);
+                        last = *x;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut last = 0;
+        while remaining.load(SeqCst) > 0 {
+            if let Success(x) = q.steal() {
+                assert!(last < *x);
+                last = *x;
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn stress() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let q = Injector::new();
+    let done = Arc::new(AtomicBool::new(false));
+    let hits = Arc::new(AtomicUsize::new(0));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let done = done.clone();
+            let hits = hits.clone();
+            let q = &q;
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = q.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = q.steal_batch(&w2);
+
+                    if let Success(_) = q.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut expected = 0;
+        while expected < COUNT {
+            if rng.gen_range(0..3) == 0 {
+                while let Success(_) = q.steal() {
+                    hits.fetch_add(1, SeqCst);
+                }
+            } else {
+                q.push(expected);
+                expected += 1;
+            }
+        }
+
+        while hits.load(SeqCst) < COUNT {
+            while let Success(_) = q.steal() {
+                hits.fetch_add(1, SeqCst);
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[cfg_attr(miri, ignore)] // Miri is too slow
+#[test]
+fn no_starvation() {
+    const THREADS: usize = 8;
+    const COUNT: usize = 50_000;
+
+    let q = Injector::new();
+    let done = Arc::new(AtomicBool::new(false));
+    let mut all_hits = Vec::new();
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let done = done.clone();
+            let hits = Arc::new(AtomicUsize::new(0));
+            all_hits.push(hits.clone());
+            let q = &q;
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = q.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = q.steal_batch(&w2);
+
+                    if let Success(_) = q.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut my_hits = 0;
+        loop {
+            for i in 0..rng.gen_range(0..COUNT) {
+                if rng.gen_range(0..3) == 0 && my_hits == 0 {
+                    while let Success(_) = q.steal() {
+                        my_hits += 1;
+                    }
+                } else {
+                    q.push(i);
+                }
+            }
+
+            if my_hits > 0 && all_hits.iter().all(|h| h.load(SeqCst) > 0) {
+                break;
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[test]
+fn destructors() {
+    #[cfg(miri)]
+    const THREADS: usize = 2;
+    #[cfg(not(miri))]
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+    #[cfg(miri)]
+    const STEPS: usize = 100;
+    #[cfg(not(miri))]
+    const STEPS: usize = 1000;
+
+    struct Elem(usize, Arc<Mutex<Vec<usize>>>);
+
+    impl Drop for Elem {
+        fn drop(&mut self) {
+            self.1.lock().unwrap().push(self.0);
+        }
+    }
+
+    let q = Injector::new();
+    let dropped = Arc::new(Mutex::new(Vec::new()));
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    for i in 0..COUNT {
+        q.push(Elem(i, dropped.clone()));
+    }
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let remaining = remaining.clone();
+            let q = &q;
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_fifo();
+                let mut cnt = 0;
+
+                while cnt < STEPS {
+                    if let Success(_) = q.steal() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    let _ = q.steal_batch(&w2);
+
+                    if let Success(_) = q.steal_batch_and_pop(&w2) {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        for _ in 0..STEPS {
+            if let Success(_) = q.steal() {
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+
+    let rem = remaining.load(SeqCst);
+    assert!(rem > 0);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), COUNT - rem);
+        v.clear();
+    }
+
+    drop(q);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), rem);
+        v.sort_unstable();
+        for pair in v.windows(2) {
+            assert_eq!(pair[0] + 1, pair[1]);
+        }
+    }
+}
diff --git a/vendor/crossbeam-deque/tests/lifo.rs b/vendor/crossbeam-deque/tests/lifo.rs
new file mode 100644
index 0000000..c1a65cd
--- /dev/null
+++ b/vendor/crossbeam-deque/tests/lifo.rs
@@ -0,0 +1,359 @@
+use std::sync::atomic::Ordering::SeqCst;
+use std::sync::atomic::{AtomicBool, AtomicUsize};
+use std::sync::{Arc, Mutex};
+
+use crossbeam_deque::Steal::{Empty, Success};
+use crossbeam_deque::Worker;
+use crossbeam_utils::thread::scope;
+use rand::Rng;
+
+#[test]
+fn smoke() {
+    let w = Worker::new_lifo();
+    let s = w.stealer();
+    assert_eq!(w.pop(), None);
+    assert_eq!(s.steal(), Empty);
+
+    w.push(1);
+    assert_eq!(w.pop(), Some(1));
+    assert_eq!(w.pop(), None);
+    assert_eq!(s.steal(), Empty);
+
+    w.push(2);
+    assert_eq!(s.steal(), Success(2));
+    assert_eq!(s.steal(), Empty);
+    assert_eq!(w.pop(), None);
+
+    w.push(3);
+    w.push(4);
+    w.push(5);
+    assert_eq!(s.steal(), Success(3));
+    assert_eq!(s.steal(), Success(4));
+    assert_eq!(s.steal(), Success(5));
+    assert_eq!(s.steal(), Empty);
+
+    w.push(6);
+    w.push(7);
+    w.push(8);
+    w.push(9);
+    assert_eq!(w.pop(), Some(9));
+    assert_eq!(s.steal(), Success(6));
+    assert_eq!(w.pop(), Some(8));
+    assert_eq!(w.pop(), Some(7));
+    assert_eq!(w.pop(), None);
+}
+
+#[test]
+fn is_empty() {
+    let w = Worker::new_lifo();
+    let s = w.stealer();
+
+    assert!(w.is_empty());
+    w.push(1);
+    assert!(!w.is_empty());
+    w.push(2);
+    assert!(!w.is_empty());
+    let _ = w.pop();
+    assert!(!w.is_empty());
+    let _ = w.pop();
+    assert!(w.is_empty());
+
+    assert!(s.is_empty());
+    w.push(1);
+    assert!(!s.is_empty());
+    w.push(2);
+    assert!(!s.is_empty());
+    let _ = s.steal();
+    assert!(!s.is_empty());
+    let _ = s.steal();
+    assert!(s.is_empty());
+}
+
+#[test]
+fn spsc() {
+    #[cfg(miri)]
+    const STEPS: usize = 500;
+    #[cfg(not(miri))]
+    const STEPS: usize = 50_000;
+
+    let w = Worker::new_lifo();
+    let s = w.stealer();
+
+    scope(|scope| {
+        scope.spawn(|_| {
+            for i in 0..STEPS {
+                loop {
+                    if let Success(v) = s.steal() {
+                        assert_eq!(i, v);
+                        break;
+                    }
+                    #[cfg(miri)]
+                    std::hint::spin_loop();
+                }
+            }
+
+            assert_eq!(s.steal(), Empty);
+        });
+
+        for i in 0..STEPS {
+            w.push(i);
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn stampede() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_lifo();
+
+    for i in 0..COUNT {
+        w.push(Box::new(i + 1));
+    }
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let remaining = remaining.clone();
+
+            scope.spawn(move |_| {
+                let mut last = 0;
+                while remaining.load(SeqCst) > 0 {
+                    if let Success(x) = s.steal() {
+                        assert!(last < *x);
+                        last = *x;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut last = COUNT + 1;
+        while remaining.load(SeqCst) > 0 {
+            if let Some(x) = w.pop() {
+                assert!(last > *x);
+                last = *x;
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+}
+
+#[test]
+fn stress() {
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_lifo();
+    let done = Arc::new(AtomicBool::new(false));
+    let hits = Arc::new(AtomicUsize::new(0));
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let done = done.clone();
+            let hits = hits.clone();
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_lifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = s.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut expected = 0;
+        while expected < COUNT {
+            if rng.gen_range(0..3) == 0 {
+                while w.pop().is_some() {
+                    hits.fetch_add(1, SeqCst);
+                }
+            } else {
+                w.push(expected);
+                expected += 1;
+            }
+        }
+
+        while hits.load(SeqCst) < COUNT {
+            while w.pop().is_some() {
+                hits.fetch_add(1, SeqCst);
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[cfg_attr(miri, ignore)] // Miri is too slow
+#[test]
+fn no_starvation() {
+    const THREADS: usize = 8;
+    const COUNT: usize = 50_000;
+
+    let w = Worker::new_lifo();
+    let done = Arc::new(AtomicBool::new(false));
+    let mut all_hits = Vec::new();
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let s = w.stealer();
+            let done = done.clone();
+            let hits = Arc::new(AtomicUsize::new(0));
+            all_hits.push(hits.clone());
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_lifo();
+
+                while !done.load(SeqCst) {
+                    if let Success(_) = s.steal() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        hits.fetch_add(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        hits.fetch_add(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        let mut rng = rand::thread_rng();
+        let mut my_hits = 0;
+        loop {
+            for i in 0..rng.gen_range(0..COUNT) {
+                if rng.gen_range(0..3) == 0 && my_hits == 0 {
+                    while w.pop().is_some() {
+                        my_hits += 1;
+                    }
+                } else {
+                    w.push(i);
+                }
+            }
+
+            if my_hits > 0 && all_hits.iter().all(|h| h.load(SeqCst) > 0) {
+                break;
+            }
+        }
+        done.store(true, SeqCst);
+    })
+    .unwrap();
+}
+
+#[test]
+fn destructors() {
+    #[cfg(miri)]
+    const THREADS: usize = 2;
+    #[cfg(not(miri))]
+    const THREADS: usize = 8;
+    #[cfg(miri)]
+    const COUNT: usize = 500;
+    #[cfg(not(miri))]
+    const COUNT: usize = 50_000;
+    #[cfg(miri)]
+    const STEPS: usize = 100;
+    #[cfg(not(miri))]
+    const STEPS: usize = 1000;
+
+    struct Elem(usize, Arc<Mutex<Vec<usize>>>);
+
+    impl Drop for Elem {
+        fn drop(&mut self) {
+            self.1.lock().unwrap().push(self.0);
+        }
+    }
+
+    let w = Worker::new_lifo();
+    let dropped = Arc::new(Mutex::new(Vec::new()));
+    let remaining = Arc::new(AtomicUsize::new(COUNT));
+
+    for i in 0..COUNT {
+        w.push(Elem(i, dropped.clone()));
+    }
+
+    scope(|scope| {
+        for _ in 0..THREADS {
+            let remaining = remaining.clone();
+            let s = w.stealer();
+
+            scope.spawn(move |_| {
+                let w2 = Worker::new_lifo();
+                let mut cnt = 0;
+
+                while cnt < STEPS {
+                    if let Success(_) = s.steal() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    let _ = s.steal_batch(&w2);
+
+                    if let Success(_) = s.steal_batch_and_pop(&w2) {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+
+                    while w2.pop().is_some() {
+                        cnt += 1;
+                        remaining.fetch_sub(1, SeqCst);
+                    }
+                }
+            });
+        }
+
+        for _ in 0..STEPS {
+            if w.pop().is_some() {
+                remaining.fetch_sub(1, SeqCst);
+            }
+        }
+    })
+    .unwrap();
+
+    let rem = remaining.load(SeqCst);
+    assert!(rem > 0);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), COUNT - rem);
+        v.clear();
+    }
+
+    drop(w);
+
+    {
+        let mut v = dropped.lock().unwrap();
+        assert_eq!(v.len(), rem);
+        v.sort_unstable();
+        for pair in v.windows(2) {
+            assert_eq!(pair[0] + 1, pair[1]);
+        }
+    }
+}
diff --git a/vendor/crossbeam-deque/tests/steal.rs b/vendor/crossbeam-deque/tests/steal.rs
new file mode 100644
index 0000000..af24998
--- /dev/null
+++ b/vendor/crossbeam-deque/tests/steal.rs
@@ -0,0 +1,212 @@
+use crossbeam_deque::Steal::Success;
+use crossbeam_deque::{Injector, Worker};
+
+#[test]
+fn steal_fifo() {
+    let w = Worker::new_fifo();
+    for i in 1..=3 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    assert_eq!(s.steal(), Success(1));
+    assert_eq!(s.steal(), Success(2));
+    assert_eq!(s.steal(), Success(3));
+}
+
+#[test]
+fn steal_lifo() {
+    let w = Worker::new_lifo();
+    for i in 1..=3 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    assert_eq!(s.steal(), Success(1));
+    assert_eq!(s.steal(), Success(2));
+    assert_eq!(s.steal(), Success(3));
+}
+
+#[test]
+fn steal_injector() {
+    let q = Injector::new();
+    for i in 1..=3 {
+        q.push(i);
+    }
+
+    assert_eq!(q.steal(), Success(1));
+    assert_eq!(q.steal(), Success(2));
+    assert_eq!(q.steal(), Success(3));
+}
+
+#[test]
+fn steal_batch_fifo_fifo() {
+    let w = Worker::new_fifo();
+    for i in 1..=4 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_fifo();
+
+    assert_eq!(s.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(1));
+    assert_eq!(w2.pop(), Some(2));
+}
+
+#[test]
+fn steal_batch_lifo_lifo() {
+    let w = Worker::new_lifo();
+    for i in 1..=4 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_lifo();
+
+    assert_eq!(s.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(1));
+}
+
+#[test]
+fn steal_batch_fifo_lifo() {
+    let w = Worker::new_fifo();
+    for i in 1..=4 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_lifo();
+
+    assert_eq!(s.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(1));
+    assert_eq!(w2.pop(), Some(2));
+}
+
+#[test]
+fn steal_batch_lifo_fifo() {
+    let w = Worker::new_lifo();
+    for i in 1..=4 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_fifo();
+
+    assert_eq!(s.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(1));
+}
+
+#[test]
+fn steal_batch_injector_fifo() {
+    let q = Injector::new();
+    for i in 1..=4 {
+        q.push(i);
+    }
+
+    let w2 = Worker::new_fifo();
+    assert_eq!(q.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(1));
+    assert_eq!(w2.pop(), Some(2));
+}
+
+#[test]
+fn steal_batch_injector_lifo() {
+    let q = Injector::new();
+    for i in 1..=4 {
+        q.push(i);
+    }
+
+    let w2 = Worker::new_lifo();
+    assert_eq!(q.steal_batch(&w2), Success(()));
+    assert_eq!(w2.pop(), Some(1));
+    assert_eq!(w2.pop(), Some(2));
+}
+
+#[test]
+fn steal_batch_and_pop_fifo_fifo() {
+    let w = Worker::new_fifo();
+    for i in 1..=6 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_fifo();
+
+    assert_eq!(s.steal_batch_and_pop(&w2), Success(1));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(3));
+}
+
+#[test]
+fn steal_batch_and_pop_lifo_lifo() {
+    let w = Worker::new_lifo();
+    for i in 1..=6 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_lifo();
+
+    assert_eq!(s.steal_batch_and_pop(&w2), Success(3));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(1));
+}
+
+#[test]
+fn steal_batch_and_pop_fifo_lifo() {
+    let w = Worker::new_fifo();
+    for i in 1..=6 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_lifo();
+
+    assert_eq!(s.steal_batch_and_pop(&w2), Success(1));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(3));
+}
+
+#[test]
+fn steal_batch_and_pop_lifo_fifo() {
+    let w = Worker::new_lifo();
+    for i in 1..=6 {
+        w.push(i);
+    }
+
+    let s = w.stealer();
+    let w2 = Worker::new_fifo();
+
+    assert_eq!(s.steal_batch_and_pop(&w2), Success(3));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(1));
+}
+
+#[test]
+fn steal_batch_and_pop_injector_fifo() {
+    let q = Injector::new();
+    for i in 1..=6 {
+        q.push(i);
+    }
+
+    let w2 = Worker::new_fifo();
+    assert_eq!(q.steal_batch_and_pop(&w2), Success(1));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(3));
+}
+
+#[test]
+fn steal_batch_and_pop_injector_lifo() {
+    let q = Injector::new();
+    for i in 1..=6 {
+        q.push(i);
+    }
+
+    let w2 = Worker::new_lifo();
+    assert_eq!(q.steal_batch_and_pop(&w2), Success(1));
+    assert_eq!(w2.pop(), Some(2));
+    assert_eq!(w2.pop(), Some(3));
+}