index_type 0.2.1

Type-safe newtype indices for Rust
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
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149

use core::num::{NonZeroU8, NonZeroUsize};
use index_type::{
    IndexType, typed_array::TypedArray, typed_array_vec::TypedArrayVec, typed_slice::TypedSlice,
    typed_vec::TypedVec,
};

#[derive(IndexType, Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
struct MyIndex(u32);

#[test]
fn test_nonzero_index() {
    #[derive(IndexType, Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
    struct NonZeroIndex(NonZeroUsize);

    let mut vec: TypedVec<NonZeroIndex, i32> = TypedVec::new();
    let idx0 = vec.push(100);
    assert_eq!(vec[idx0], 100);
    assert_eq!(idx0.to_raw_index(), 0);
}

#[test]
fn test_binary_search() {
    let mut vec: TypedVec<MyIndex, i32> = TypedVec::new();
    vec.push(10);
    vec.push(20);
    vec.push(30);
    vec.push(40);

    assert_eq!(
        vec.binary_search(&20),
        Ok(unsafe { MyIndex::from_raw_index_unchecked(1) })
    );
    assert_eq!(
        vec.binary_search(&25),
        Err(unsafe { MyIndex::from_raw_index_unchecked(2) })
    );
}

#[test]
fn test_get_disjoint_mut() {
    let mut vec: TypedVec<MyIndex, i32> = TypedVec::new();
    vec.push(10);
    vec.push(20);
    vec.push(30);

    let [a, b] = vec
        .get_disjoint_mut([MyIndex::ZERO, unsafe {
            MyIndex::from_raw_index_unchecked(2)
        }])
        .unwrap();
    *a += 1;
    *b += 1;

    assert_eq!(vec[MyIndex::ZERO], 11);
    assert_eq!(vec[unsafe { MyIndex::from_raw_index_unchecked(2) }], 31);

    // Overlapping indices should fail
    assert!(
        vec.get_disjoint_mut([MyIndex::ZERO, MyIndex::ZERO])
            .is_err()
    );
}

#[test]
fn test_nonzero_capacity_limit() {
    #[derive(IndexType, Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
    struct NonZeroSmallIndex(NonZeroU8);

    let mut vec: TypedVec<NonZeroSmallIndex, i32> = TypedVec::new();
    // NonZeroU8 MAX is 255. ZERO is 1. MAX_RAW_INDEX is 254.
    // Raw indices are 0..=254.
    for i in 0..254 {
        vec.push(i);
    }
    assert_eq!(vec.len_usize(), 254);
    // When len is 254, push returns raw index 254 and len becomes 255.
    // checked_add_scalar(254, 1) returns Err because 255 > 254.
    assert!(vec.try_push(254).is_err());
}

#[test]
fn test_nonzero_checked_mul_scalar_uses_raw_index_semantics() {
    let idx = NonZeroU8::try_from_raw_index(2).unwrap();
    assert_eq!(idx.checked_mul_scalar(2).unwrap().to_raw_index(), 4);

    let zero = NonZeroU8::ZERO;
    assert_eq!(zero.checked_mul_scalar(10).unwrap().to_raw_index(), 0);

    assert!(NonZeroU8::MAX_INDEX.checked_mul_scalar(2).is_err());
}

#[test]
fn test_macros() {
    use index_type::{typed_array, typed_array_vec, typed_slice, typed_slice_mut, typed_vec};

    // Test typed_array_vec!
    let av: TypedArrayVec<MyIndex, i32, 3> = typed_array_vec![1, 2, 3];
    assert_eq!(av.len_usize(), 3);
    assert_eq!(av[MyIndex::ZERO], 1);

    let av2: TypedArrayVec<MyIndex, i32, 5> = typed_array_vec![0; 5];
    assert_eq!(av2.len_usize(), 5);
    assert_eq!(av2[MyIndex::ZERO], 0);

    // Ensure it works with non-const lengths
    let count = 4;
    let av3: TypedArrayVec<MyIndex, i32, 4> = typed_array_vec![1; count];
    assert_eq!(av3.len_usize(), 4);
    assert_eq!(av3[MyIndex::ZERO], 1);

    // Test typed_vec!
    let v: TypedVec<MyIndex, i32> = typed_vec![1, 2, 3];
    assert_eq!(v.len_usize(), 3);
    assert_eq!(v[MyIndex::ZERO], 1);

    let v2: TypedVec<MyIndex, i32> = typed_vec![0; 5];
    assert_eq!(v2.len_usize(), 5);
    assert_eq!(v2[MyIndex::ZERO], 0);

    // Test typed_array!
    let a: TypedArray<MyIndex, i32, 3> = typed_array![1, 2, 3];
    assert_eq!(a.len_usize(), 3);
    assert_eq!(a[MyIndex::ZERO], 1);

    let a2: TypedArray<MyIndex, i32, 5> = typed_array![0; 5];
    assert_eq!(a2.len_usize(), 5);
    assert_eq!(a2[MyIndex::ZERO], 0);

    // Test typed_slice!
    let s: &TypedSlice<MyIndex, i32> = typed_slice![1, 2, 3];
    assert_eq!(s.len_usize(), 3);
    assert_eq!(s[MyIndex::ZERO], 1);

    // Test typed_slice_mut!
    fn check_typed_slice_mut(s: &mut TypedSlice<MyIndex, i32>) {
        assert_eq!(s.len_usize(), 3);
        assert_eq!(s[MyIndex::ZERO], 1);
        s[MyIndex::ZERO] = 10;
        assert_eq!(s[MyIndex::ZERO], 10);
    }
    check_typed_slice_mut(typed_slice_mut![1, 2, 3]);

    // Basic verify of macro existence and return types
    let _v: TypedVec<MyIndex, i32> = typed_vec![1, 2, 3];
    let _a: TypedArray<MyIndex, i32, 3> = typed_array![1, 2, 3];
    let _av: TypedArrayVec<MyIndex, i32, 3> = typed_array_vec![1, 2, 3];
    let _s: &TypedSlice<MyIndex, i32> = typed_slice![1, 2, 3];
    let _s: &mut TypedSlice<MyIndex, i32> = typed_slice_mut![1, 2, 3];
}