vecpool 0.1.0

Thread-local pool of reusable Vec buffers with cross-type reuse
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
150
151
152
153
154
155

use std::sync::Arc;
use vecpool::get;

#[test]
fn buffer_reuse() {
    let mut v = get::<u32>();
    v.push(1);
    v.push(2);
    v.push(3);
    drop(v);

    let v2 = get::<u32>();
    assert!(v2.capacity() > 0);
}

#[test]
fn cross_type_reuse() {
    let mut v = get::<i32>();
    v.push(1);
    v.push(2);
    drop(v);

    let v2 = get::<u32>();
    assert!(v2.capacity() > 0);
}

#[test]
fn no_cross_layout_reuse() {
    let mut v = get::<u8>();
    v.push(1);
    v.push(2);
    drop(v);

    let v2 = get::<u32>();
    assert_eq!(v2.capacity(), 0);
}

#[test]
fn zst_handling() {
    let mut v = get::<()>();
    v.push(());
    v.push(());
    drop(v);

    let mut v2 = get::<()>();
    v2.push(());
}

#[test]
fn deref_deref_mut() {
    let mut v = get::<u32>();
    v.push(10);
    v.push(20);
    assert_eq!(v.len(), 2);
    assert_eq!(v[0], 10);
    assert_eq!(v[1], 20);
}

#[test]
fn debug_impl() {
    let mut v = get::<u32>();
    v.push(1);
    v.push(2);
    let s = format!("{:?}", v);
    assert_eq!(s, "[1, 2]");
}

#[test]
fn drop_clears_elements() {
    let arc = Arc::new(42);
    {
        let mut v = get::<Arc<i32>>();
        v.push(arc.clone());
        v.push(arc.clone());
    }
    assert_eq!(Arc::strong_count(&arc), 1);
}

#[test]
fn with_capacity_reuses_large_enough_buffer() {
    let mut v = vecpool::get::<u32>();
    for i in 0..200 {
        v.push(i);
    }
    let cap = v.capacity();
    drop(v);

    let v2 = vecpool::with_capacity::<u32>(100);
    assert!(v2.capacity() >= 100);
    assert_eq!(v2.capacity(), cap);
}

#[test]
fn with_capacity_allocates_fresh_if_pool_too_small() {
    // Ensure pool has a small buffer
    let mut v = vecpool::get::<u32>();
    v.push(1);
    drop(v);

    let v2 = vecpool::with_capacity::<u32>(1000);
    assert!(v2.capacity() >= 1000);
}

#[test]
fn pool_vec_new() {
    let mut v = vecpool::PoolVec::<u32>::new();
    v.push(42);
    assert_eq!(v[0], 42);
}

#[test]
fn into_iterator() {
    let mut v = vecpool::get::<u32>();
    v.push(1);
    v.push(2);
    v.push(3);

    let collected: Vec<u32> = v.into_iter().collect();
    assert_eq!(collected, vec![1, 2, 3]);
}

#[test]
fn from_vec() {
    let original = vec![10u32, 20, 30];
    let pooled = vecpool::PoolVec::from(original);
    assert_eq!(pooled.len(), 3);
    assert_eq!(pooled[0], 10);
    // On drop, buffer goes to pool
    let cap = pooled.capacity();
    drop(pooled);

    let reused = vecpool::get::<u32>();
    assert_eq!(reused.capacity(), cap);
}

#[test]
fn clear_pool_frees_buffers() {
    let mut v = vecpool::get::<u32>();
    v.push(1);
    drop(v);

    vecpool::clear_pool();

    // After clearing, next get should have no capacity (fresh vec)
    let v2 = vecpool::get::<u32>();
    assert_eq!(v2.capacity(), 0);
}

#[test]
fn from_iterator() {
    let pooled: vecpool::PoolVec<u32> = (0..100).collect();
    assert_eq!(pooled.len(), 100);
    assert_eq!(pooled[0], 0);
    assert_eq!(pooled[99], 99);
}