contigious-tree 0.1.2

Write and read tree graphs to and from contigious blocks of memory.
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

use contigious_tree::{TreeBuilder, TreeVec, U8, LeI32};

#[test]
fn leaf() {
    // Given
    let mut persistence = Vec::<u8>::new();

    // When
    let mut builder = TreeBuilder::<LeI32, _>::new(&mut persistence);
    builder.write_node(&42, 0).unwrap();
    builder.finish().unwrap();
    let tree = TreeVec::<LeI32>::new(persistence);
    let (value, mut branches) = tree.read_node();

    // Then
    assert_eq!(42, value);
    assert!(branches.next().is_none());
}

#[test]
fn root_node_with_two_children() {
    // Given
    let mut persistence = Vec::<u8>::new();

    // When
    let mut builder = TreeBuilder::<U8, _>::new(&mut persistence);
    // First child
    builder.write_node(&1, 0).unwrap();
    // Second child
    builder.write_node(&2, 0).unwrap();
    // Parent
    builder.write_node(&3, 2).unwrap();
    builder.finish().unwrap();
    // Read tree
    let tree = TreeVec::<U8>::new(persistence);

    // Then
    let (value, mut branches) = tree.read_node();
    assert_eq!(3, value);
    let second = branches.next().unwrap();
    let first = branches.next().unwrap();
    assert!(branches.next().is_none());
    let (value, mut branches) = second.read_node();
    assert_eq!(2, value);
    assert!(branches.next().is_none());
    let (value, mut branches) = first.read_node();
    assert_eq!(1, value);
    assert!(branches.next().is_none())
}

#[test]
fn three_successive_nodes() {
    // Given
    let mut persistence = Vec::<u8>::new();

    // When
    let mut builder = TreeBuilder::<U8, _>::new(&mut persistence);
    // First child
    builder.write_node(&1, 0).unwrap();
    // Second child
    builder.write_node(&2, 1).unwrap();
    // Parent
    builder.write_node(&3, 1).unwrap();
    builder.finish().unwrap();
    // Read tree
    let tree = TreeVec::<U8>::new(persistence);

    // Then
    let (value, mut branches) = tree.read_node();
    assert_eq!(3, value);
    let tree_slice = branches.next().unwrap();
    assert!(branches.next().is_none());
    let (value, mut branches) = tree_slice.read_node();
    assert_eq!(2, value);
    let tree_slice = branches.next().unwrap();
    assert!(branches.next().is_none());
    let (value, mut branches) = tree_slice.read_node();
    assert_eq!(1, value);
    assert!(branches.next().is_none())
}