crossbeam-skiplist_piedb 0.8.11

#![allow(clippy::mutex_atomic)]

use std::{iter, ops::Bound, sync::Barrier};

use crossbeam_skiplist::SkipMap;
use crossbeam_utils::thread;

#[test]
fn smoke() {
    let m = SkipMap::new();
    m.insert(1, 10);
    m.insert(5, 50);
    m.insert(7, 70);
}

#[test]
fn is_empty() {
    let s = SkipMap::new();
    assert!(s.is_empty());

    s.insert(1, 10);
    assert!(!s.is_empty());
    s.insert(2, 20);
    s.insert(3, 30);
    assert!(!s.is_empty());

    s.remove(&2);
    assert!(!s.is_empty());

    s.remove(&1);
    assert!(!s.is_empty());

    s.remove(&3);
    assert!(s.is_empty());
}

#[test]
fn insert() {
    let insert = [0, 4, 2, 12, 8, 7, 11, 5];
    let not_present = [1, 3, 6, 9, 10];
    let s = SkipMap::new();

    for &x in &insert {
        s.insert(x, x * 10);
        assert_eq!(*s.get(&x).unwrap().value(), x * 10);
    }

    for &x in &not_present {
        assert!(s.get(&x).is_none());
    }
}

#[test]
fn remove() {
    let insert = [0, 4, 2, 12, 8, 7, 11, 5];
    let not_present = [1, 3, 6, 9, 10];
    let remove = [2, 12, 8];
    let remaining = [0, 4, 5, 7, 11];

    let s = SkipMap::new();

    for &x in &insert {
        s.insert(x, x * 10);
    }
    for x in &not_present {
        assert!(s.remove(x).is_none());
    }
    for x in &remove {
        assert!(s.remove(x).is_some());
    }

    let mut v = vec![];
    let mut e = s.front().unwrap();
    loop {
        v.push(*e.key());
        if !e.move_next() {
            break;
        }
    }

    assert_eq!(v, remaining);
    for x in &insert {
        s.remove(x);
    }
    assert!(s.is_empty());
}

// https://github.com/crossbeam-rs/crossbeam/issues/672
#[test]
fn concurrent_insert() {
    for _ in 0..100 {
        let set: SkipMap<i32, i32> = iter::once((1, 1)).collect();
        let barrier = Barrier::new(2);
        thread::scope(|s| {
            s.spawn(|_| {
                barrier.wait();
                set.insert(1, 1);
            });
            s.spawn(|_| {
                barrier.wait();
                set.insert(1, 1);
            });
        })
        .unwrap();
    }
}

// https://github.com/crossbeam-rs/crossbeam/issues/672
#[test]
fn concurrent_remove() {
    for _ in 0..100 {
        let set: SkipMap<i32, i32> = iter::once((1, 1)).collect();
        let barrier = Barrier::new(2);
        thread::scope(|s| {
            s.spawn(|_| {
                barrier.wait();
                set.remove(&1);
            });
            s.spawn(|_| {
                barrier.wait();
                set.remove(&1);
            });
        })
        .unwrap();
    }
}

#[test]
fn next_memory_leak() {
    let map: SkipMap<i32, i32> = iter::once((1, 1)).collect();
    let mut iter = map.iter();
    let e = iter.next_back();
    assert!(e.is_some());
    let e = iter.next();
    assert!(e.is_none());
    map.remove(&1);
}

#[test]
fn next_back_memory_leak() {
    let map: SkipMap<i32, i32> = iter::once((1, 1)).collect();
    map.insert(1, 1);
    let mut iter = map.iter();
    let e = iter.next();
    assert!(e.is_some());
    let e = iter.next_back();
    assert!(e.is_none());
    map.remove(&1);
}

#[test]
fn range_next_memory_leak() {
    let map: SkipMap<i32, i32> = iter::once((1, 1)).collect();
    let mut iter = map.range(0..);
    let e = iter.next();
    assert!(e.is_some());
    let e = iter.next_back();
    assert!(e.is_none());
    map.remove(&1);
}

#[test]
fn entry() {
    let s = SkipMap::new();

    assert!(s.front().is_none());
    assert!(s.back().is_none());

    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    let mut e = s.front().unwrap();
    assert_eq!(*e.key(), 2);
    assert!(!e.move_prev());
    assert!(e.move_next());
    assert_eq!(*e.key(), 4);

    e = s.back().unwrap();
    assert_eq!(*e.key(), 12);
    assert!(!e.move_next());
    assert!(e.move_prev());
    assert_eq!(*e.key(), 11);
}

#[test]
fn ordered_iter() {
    let s: SkipMap<i32, i32> = SkipMap::new();
    s.insert(1, 1);

    let mut iter = s.iter();
    assert!(iter.next().is_some());
    assert!(iter.next().is_none());
    assert!(iter.next().is_none());

    s.insert(2, 2);
    assert!(iter.next().is_some());
    assert!(iter.next().is_none());
    assert!(iter.next().is_none());

    s.insert(3, 3);
    s.insert(4, 4);
    s.insert(5, 5);
    assert_eq!(*iter.next_back().unwrap().key(), 5);
    assert_eq!(*iter.next().unwrap().key(), 3);
    assert_eq!(*iter.next_back().unwrap().key(), 4);
    assert!(iter.next().is_none());
    assert!(iter.next_back().is_none());
    assert!(iter.next().is_none());
    assert!(iter.next_back().is_none());
}

#[test]
fn ordered_range() {
    let s: SkipMap<i32, i32> = SkipMap::new();
    s.insert(1, 1);

    let mut iter = s.range(0..);
    assert!(iter.next().is_some());
    assert!(iter.next().is_none());
    assert!(iter.next().is_none());

    s.insert(2, 2);
    assert!(iter.next().is_some());
    assert!(iter.next().is_none());
    assert!(iter.next().is_none());

    s.insert(3, 3);
    s.insert(4, 4);
    s.insert(5, 5);
    assert_eq!(*iter.next_back().unwrap().key(), 5);
    assert_eq!(*iter.next().unwrap().key(), 3);
    assert_eq!(*iter.next_back().unwrap().key(), 4);
    assert!(iter.next().is_none());
    assert!(iter.next_back().is_none());
    assert!(iter.next().is_none());
    assert!(iter.next_back().is_none());
}
#[test]
fn entry_remove() {
    let s = SkipMap::new();

    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    let mut e = s.get(&7).unwrap();
    assert!(!e.is_removed());
    assert!(e.remove());
    assert!(e.is_removed());

    e.move_prev();
    e.move_next();
    assert_ne!(*e.key(), 7);

    for e in s.iter() {
        assert!(!s.is_empty());
        assert_ne!(s.len(), 0);
        e.remove();
    }
    assert!(s.is_empty());
    assert_eq!(s.len(), 0);
}

#[test]
fn entry_reposition() {
    let s = SkipMap::new();

    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    let mut e = s.get(&7).unwrap();
    assert!(!e.is_removed());
    assert!(e.remove());
    assert!(e.is_removed());

    s.insert(7, 700);
    e.move_prev();
    e.move_next();
    assert_eq!(*e.key(), 7);
}

#[test]
fn len() {
    let s = SkipMap::new();
    assert_eq!(s.len(), 0);

    for (i, &x) in [4, 2, 12, 8, 7, 11, 5].iter().enumerate() {
        s.insert(x, x * 10);
        assert_eq!(s.len(), i + 1);
    }

    s.insert(5, 0);
    assert_eq!(s.len(), 7);
    s.insert(5, 0);
    assert_eq!(s.len(), 7);

    s.remove(&6);
    assert_eq!(s.len(), 7);
    s.remove(&5);
    assert_eq!(s.len(), 6);
    s.remove(&12);
    assert_eq!(s.len(), 5);
}

#[test]
fn insert_and_remove() {
    let s = SkipMap::new();
    let keys = || s.iter().map(|e| *e.key()).collect::<Vec<_>>();

    s.insert(3, 0);
    s.insert(5, 0);
    s.insert(1, 0);
    s.insert(4, 0);
    s.insert(2, 0);
    assert_eq!(keys(), [1, 2, 3, 4, 5]);

    assert!(s.remove(&4).is_some());
    assert_eq!(keys(), [1, 2, 3, 5]);
    assert!(s.remove(&3).is_some());
    assert_eq!(keys(), [1, 2, 5]);
    assert!(s.remove(&1).is_some());
    assert_eq!(keys(), [2, 5]);

    assert!(s.remove(&1).is_none());
    assert_eq!(keys(), [2, 5]);
    assert!(s.remove(&3).is_none());
    assert_eq!(keys(), [2, 5]);

    assert!(s.remove(&2).is_some());
    assert_eq!(keys(), [5]);
    assert!(s.remove(&5).is_some());
    assert_eq!(keys(), []);

    s.insert(3, 0);
    assert_eq!(keys(), [3]);
    s.insert(1, 0);
    assert_eq!(keys(), [1, 3]);
    s.insert(3, 0);
    assert_eq!(keys(), [1, 3]);
    s.insert(5, 0);
    assert_eq!(keys(), [1, 3, 5]);

    assert!(s.remove(&3).is_some());
    assert_eq!(keys(), [1, 5]);
    assert!(s.remove(&1).is_some());
    assert_eq!(keys(), [5]);
    assert!(s.remove(&3).is_none());
    assert_eq!(keys(), [5]);
    assert!(s.remove(&5).is_some());
    assert_eq!(keys(), []);
}

#[test]
fn get() {
    let s = SkipMap::new();
    s.insert(30, 3);
    s.insert(50, 5);
    s.insert(10, 1);
    s.insert(40, 4);
    s.insert(20, 2);

    assert_eq!(*s.get(&10).unwrap().value(), 1);
    assert_eq!(*s.get(&20).unwrap().value(), 2);
    assert_eq!(*s.get(&30).unwrap().value(), 3);
    assert_eq!(*s.get(&40).unwrap().value(), 4);
    assert_eq!(*s.get(&50).unwrap().value(), 5);

    assert!(s.get(&7).is_none());
    assert!(s.get(&27).is_none());
    assert!(s.get(&31).is_none());
    assert!(s.get(&97).is_none());
}

#[test]
fn lower_bound() {
    let s = SkipMap::new();
    s.insert(30, 3);
    s.insert(50, 5);
    s.insert(10, 1);
    s.insert(40, 4);
    s.insert(20, 2);

    assert_eq!(*s.lower_bound(Bound::Unbounded).unwrap().value(), 1);

    assert_eq!(*s.lower_bound(Bound::Included(&10)).unwrap().value(), 1);
    assert_eq!(*s.lower_bound(Bound::Included(&20)).unwrap().value(), 2);
    assert_eq!(*s.lower_bound(Bound::Included(&30)).unwrap().value(), 3);
    assert_eq!(*s.lower_bound(Bound::Included(&40)).unwrap().value(), 4);
    assert_eq!(*s.lower_bound(Bound::Included(&50)).unwrap().value(), 5);

    assert_eq!(*s.lower_bound(Bound::Included(&7)).unwrap().value(), 1);
    assert_eq!(*s.lower_bound(Bound::Included(&27)).unwrap().value(), 3);
    assert_eq!(*s.lower_bound(Bound::Included(&31)).unwrap().value(), 4);
    assert!(s.lower_bound(Bound::Included(&97)).is_none());

    assert_eq!(*s.lower_bound(Bound::Excluded(&10)).unwrap().value(), 2);
    assert_eq!(*s.lower_bound(Bound::Excluded(&20)).unwrap().value(), 3);
    assert_eq!(*s.lower_bound(Bound::Excluded(&30)).unwrap().value(), 4);
    assert_eq!(*s.lower_bound(Bound::Excluded(&40)).unwrap().value(), 5);
    assert!(s.lower_bound(Bound::Excluded(&50)).is_none());

    assert_eq!(*s.lower_bound(Bound::Excluded(&7)).unwrap().value(), 1);
    assert_eq!(*s.lower_bound(Bound::Excluded(&27)).unwrap().value(), 3);
    assert_eq!(*s.lower_bound(Bound::Excluded(&31)).unwrap().value(), 4);
    assert!(s.lower_bound(Bound::Excluded(&97)).is_none());
}

#[test]
fn upper_bound() {
    let s = SkipMap::new();
    s.insert(30, 3);
    s.insert(50, 5);
    s.insert(10, 1);
    s.insert(40, 4);
    s.insert(20, 2);

    assert_eq!(*s.upper_bound(Bound::Unbounded).unwrap().value(), 5);

    assert_eq!(*s.upper_bound(Bound::Included(&10)).unwrap().value(), 1);
    assert_eq!(*s.upper_bound(Bound::Included(&20)).unwrap().value(), 2);
    assert_eq!(*s.upper_bound(Bound::Included(&30)).unwrap().value(), 3);
    assert_eq!(*s.upper_bound(Bound::Included(&40)).unwrap().value(), 4);
    assert_eq!(*s.upper_bound(Bound::Included(&50)).unwrap().value(), 5);

    assert!(s.upper_bound(Bound::Included(&7)).is_none());
    assert_eq!(*s.upper_bound(Bound::Included(&27)).unwrap().value(), 2);
    assert_eq!(*s.upper_bound(Bound::Included(&31)).unwrap().value(), 3);
    assert_eq!(*s.upper_bound(Bound::Included(&97)).unwrap().value(), 5);

    assert!(s.upper_bound(Bound::Excluded(&10)).is_none());
    assert_eq!(*s.upper_bound(Bound::Excluded(&20)).unwrap().value(), 1);
    assert_eq!(*s.upper_bound(Bound::Excluded(&30)).unwrap().value(), 2);
    assert_eq!(*s.upper_bound(Bound::Excluded(&40)).unwrap().value(), 3);
    assert_eq!(*s.upper_bound(Bound::Excluded(&50)).unwrap().value(), 4);

    assert!(s.upper_bound(Bound::Excluded(&7)).is_none());
    assert_eq!(*s.upper_bound(Bound::Excluded(&27)).unwrap().value(), 2);
    assert_eq!(*s.upper_bound(Bound::Excluded(&31)).unwrap().value(), 3);
    assert_eq!(*s.upper_bound(Bound::Excluded(&97)).unwrap().value(), 5);
}

#[test]
fn get_or_insert() {
    let s = SkipMap::new();
    s.insert(3, 3);
    s.insert(5, 5);
    s.insert(1, 1);
    s.insert(4, 4);
    s.insert(2, 2);

    assert_eq!(*s.get(&4).unwrap().value(), 4);
    assert_eq!(*s.insert(4, 40).value(), 40);
    assert_eq!(*s.get(&4).unwrap().value(), 40);

    assert_eq!(*s.get_or_insert(4, 400).value(), 40);
    assert_eq!(*s.get(&4).unwrap().value(), 40);
    assert_eq!(*s.get_or_insert(6, 600).value(), 600);
}

#[test]
fn get_or_insert_with() {
    let s = SkipMap::new();
    s.insert(3, 3);
    s.insert(5, 5);
    s.insert(1, 1);
    s.insert(4, 4);
    s.insert(2, 2);

    assert_eq!(*s.get(&4).unwrap().value(), 4);
    assert_eq!(*s.insert(4, 40).value(), 40);
    assert_eq!(*s.get(&4).unwrap().value(), 40);

    assert_eq!(*s.get_or_insert_with(4, || 400).value(), 40);
    assert_eq!(*s.get(&4).unwrap().value(), 40);
    assert_eq!(*s.get_or_insert_with(6, || 600).value(), 600);
}

#[test]
fn get_or_insert_with_panic() {
    use std::panic;

    let s = SkipMap::new();
    let res = panic::catch_unwind(panic::AssertUnwindSafe(|| {
        s.get_or_insert_with(4, || panic!());
    }));
    assert!(res.is_err());
    assert!(s.is_empty());
    assert_eq!(*s.get_or_insert_with(4, || 40).value(), 40);
    assert_eq!(s.len(), 1);
}

#[test]
fn get_or_insert_with_parallel_run() {
    use std::sync::{Arc, Mutex};

    let s = Arc::new(SkipMap::new());
    let s2 = s.clone();
    let called = Arc::new(Mutex::new(false));
    let called2 = called.clone();
    let handle = std::thread::spawn(move || {
        assert_eq!(
            *s2.get_or_insert_with(7, || {
                *called2.lock().unwrap() = true;

                // allow main thread to run before we return result
                std::thread::sleep(std::time::Duration::from_secs(4));
                70
            })
            .value(),
            700
        );
    });
    std::thread::sleep(std::time::Duration::from_secs(2));

    // main thread writes the value first
    assert_eq!(*s.get_or_insert(7, 700).value(), 700);
    handle.join().unwrap();
    assert!(*called.lock().unwrap());
}

#[test]
fn get_next_prev() {
    let s = SkipMap::new();
    s.insert(3, 3);
    s.insert(5, 5);
    s.insert(1, 1);
    s.insert(4, 4);
    s.insert(2, 2);

    let mut e = s.get(&3).unwrap();
    assert_eq!(*e.next().unwrap().value(), 4);
    assert_eq!(*e.prev().unwrap().value(), 2);
    assert_eq!(*e.value(), 3);

    e.move_prev();
    assert_eq!(*e.next().unwrap().value(), 3);
    assert_eq!(*e.prev().unwrap().value(), 1);
    assert_eq!(*e.value(), 2);

    e.move_prev();
    assert_eq!(*e.next().unwrap().value(), 2);
    assert!(e.prev().is_none());
    assert_eq!(*e.value(), 1);

    e.move_next();
    e.move_next();
    e.move_next();
    e.move_next();
    assert!(e.next().is_none());
    assert_eq!(*e.prev().unwrap().value(), 4);
    assert_eq!(*e.value(), 5);
}

#[test]
fn front_and_back() {
    let s = SkipMap::new();
    assert!(s.front().is_none());
    assert!(s.back().is_none());

    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    assert_eq!(*s.front().unwrap().key(), 2);
    assert_eq!(*s.back().unwrap().key(), 12);
}

#[test]
fn iter() {
    let s = SkipMap::new();
    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    assert_eq!(
        s.iter().map(|e| *e.key()).collect::<Vec<_>>(),
        &[2, 4, 5, 7, 8, 11, 12]
    );

    let mut it = s.iter();
    s.remove(&2);
    assert_eq!(*it.next().unwrap().key(), 4);
    s.remove(&7);
    assert_eq!(*it.next().unwrap().key(), 5);
    s.remove(&5);
    assert_eq!(*it.next().unwrap().key(), 8);
    s.remove(&12);
    assert_eq!(*it.next().unwrap().key(), 11);
    assert!(it.next().is_none());
}

#[test]
fn iter_range() {
    use std::ops::Bound::*;
    let s = SkipMap::new();
    let v = (0..10).map(|x| x * 10).collect::<Vec<_>>();
    for &x in v.iter() {
        s.insert(x, x);
    }

    assert_eq!(
        s.iter().map(|x| *x.value()).collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.iter().rev().map(|x| *x.value()).collect::<Vec<_>>(),
        vec![90, 80, 70, 60, 50, 40, 30, 20, 10, 0]
    );
    assert_eq!(
        s.range(..).map(|x| *x.value()).collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70, 80, 90]
    );

    assert_eq!(
        s.range((Included(&0), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.range((Included(&0), Included(&60)))
            .rev()
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![60, 50, 40, 30, 20, 10, 0]
    );
    assert_eq!(
        s.range((Excluded(&0), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![10, 20, 30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.range((Included(&25), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.range((Excluded(&25), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.range((Included(&70), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![70, 80, 90]
    );
    assert_eq!(
        s.range((Excluded(&70), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![80, 90]
    );
    assert_eq!(
        s.range((Included(&100), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&100), Unbounded))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );

    assert_eq!(
        s.range((Unbounded, Included(&90)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70, 80, 90]
    );
    assert_eq!(
        s.range((Unbounded, Excluded(&90)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70, 80]
    );
    assert_eq!(
        s.range((Unbounded, Included(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20]
    );
    assert_eq!(
        s.range((Unbounded, Excluded(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20]
    );
    assert_eq!(
        s.range((Unbounded, Included(&70)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60, 70]
    );
    assert_eq!(
        s.range((Unbounded, Excluded(&70)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![0, 10, 20, 30, 40, 50, 60]
    );
    assert_eq!(
        s.range((Unbounded, Included(&-1)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Unbounded, Excluded(&-1)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );

    assert_eq!(
        s.range((Included(&25), Included(&80)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70, 80]
    );
    assert_eq!(
        s.range((Included(&25), Excluded(&80)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70]
    );
    assert_eq!(
        s.range((Excluded(&25), Included(&80)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70, 80]
    );
    assert_eq!(
        s.range((Excluded(&25), Excluded(&80)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![30, 40, 50, 60, 70]
    );

    assert_eq!(
        s.range((Included(&25), Included(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Included(&25), Excluded(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&25), Included(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&25), Excluded(&25)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );

    assert_eq!(
        s.range((Included(&50), Included(&50)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![50]
    );
    assert_eq!(
        s.range((Included(&50), Excluded(&50)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&50), Included(&50)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&50), Excluded(&50)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );

    assert_eq!(
        s.range((Included(&100), Included(&-2)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Included(&100), Excluded(&-2)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&100), Included(&-2)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
    assert_eq!(
        s.range((Excluded(&100), Excluded(&-2)))
            .map(|x| *x.value())
            .collect::<Vec<_>>(),
        vec![]
    );
}

// https://github.com/crossbeam-rs/crossbeam/issues/671
#[test]
fn iter_range2() {
    let set: SkipMap<_, _> = [1, 3, 5].iter().map(|x| (*x, *x)).collect();
    assert_eq!(set.range(2..4).count(), 1);
    set.insert(3, 3);
}

#[test]
fn test_shared_iter() {
    let s = SkipMap::new();
    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }
    {
        let mut it1 = s.shared_iter();
        let (k,v) = match it1.next() {
            Some((k,v)) => (k, v),
            None => (0, 0),
        };
        assert_eq!(k, 2);
        assert_eq!(v, 20);
    }
    s.insert(1, 10);
    {
        let mut it1 = s.shared_iter();
        let (k,v) = match it1.next() {
            Some((k,v)) => (k, v),
            None => (0, 0),
        };
        assert_eq!(k, 1);
        assert_eq!(v, 10);
    }
}

#[test]
fn into_iter() {
    let s = SkipMap::new();
    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    assert_eq!(
        s.into_iter().collect::<Vec<_>>(),
        &[
            (2, 20),
            (4, 40),
            (5, 50),
            (7, 70),
            (8, 80),
            (11, 110),
            (12, 120),
        ]
    );
}

#[test]
fn clear() {
    let s = SkipMap::new();
    for &x in &[4, 2, 12, 8, 7, 11, 5] {
        s.insert(x, x * 10);
    }

    assert!(!s.is_empty());
    assert_ne!(s.len(), 0);
    s.clear();
    assert!(s.is_empty());
    assert_eq!(s.len(), 0);
}