petitset 0.2.1

An ordered set data structure, optimized for stack-allocated storage of a tiny number of elements with a fixed cap.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68

use petitset::PetitMap;

#[test]
fn lookup() {
    let mut map: PetitMap<i32, i32, 4> = PetitMap::default();
    // Index 0
    map.insert(1, 11);
    // Index 1
    map.insert(3, 31);
    // Index 2
    map.insert(4, 41);
    // Index 3
    map.insert(2, 21);

    assert_eq!(*map.get(&1).unwrap(), 11);
    assert_eq!(*map.get_mut(&3).unwrap(), 31);
    assert_eq!(map.get_at(2).unwrap(), (&4, &41));
    assert_eq!(map.get_at_mut(3).unwrap(), (&mut 2, &mut 21));
}

#[test]
fn removal() {
    let mut map: PetitMap<i32, i32, 4> = PetitMap::default();
    // Index 0
    map.insert(1, 11);
    // Index 1
    map.insert(3, 31);
    // Index 2
    map.insert(4, 41);
    // Index 3
    map.insert(2, 21);

    // Overwriting insertion
    map.insert(3, 33);

    let removed = map.take(&3);
    assert_eq!(removed, Some((1, (3, 33))));
    assert_eq!(map.find(&3), None);

    let removed_at = map.take_at(0);
    assert_eq!(removed_at, Some((1, 11)));
    assert_eq!(map.find(&1), None);

    let failed_remove = map.remove_at(0);
    assert!(!failed_remove);
}

#[test]
#[should_panic]
fn panic_on_overfull_insertion() {
    let mut map: PetitMap<i32, i32, 2> = PetitMap::default();
    map.insert(1, 1);
    map.insert(2, 2);
    map.insert(3, 3);
}

#[test]
fn equality_ignores_order() {
    let mut map_1: PetitMap<i32, i32, 2> = PetitMap::default();
    map_1.insert(1, 1);
    map_1.insert(2, 2);

    let mut map_2: PetitMap<i32, i32, 2> = PetitMap::default();
    map_2.insert(2, 2);
    map_2.insert(1, 1);

    assert_eq!(map_1, map_2);
}