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
156
157
158
159
160
161
162
163
164
165
166

use std::{
    cmp::Ordering,
    hash::{Hash, Hasher},
};

use ring::digest::{digest, SHA256};
use serde::{self, Deserialize, Serialize};

/// Represents raw transaction bytes.
/// ref. https://pkg.go.dev/github.com/ava-labs/avalanchego/snow/engine/avalanche/vertex#SortHashOf
/// ref. https://docs.rs/zerocopy/latest/zerocopy/trait.AsBytes.html#safety
#[derive(Debug, Clone, Deserialize, Serialize, Eq)]
#[repr(transparent)]
pub struct Data(Vec<u8>);

impl Default for Data {
    fn default() -> Self {
        Self::default()
    }
}

impl Data {
    pub fn default() -> Self {
        Data(Vec::new())
    }

    pub fn from_slice(d: &[u8]) -> Self {
        Data(Vec::from(d))
    }
}

impl AsRef<[u8]> for Data {
    fn as_ref(&self) -> &[u8] {
        &self.0
    }
}

impl Ord for Data {
    fn cmp(&self, other: &Data) -> Ordering {
        let h1: Vec<u8> = digest(&SHA256, &self.0).as_ref().into();
        let h2: Vec<u8> = digest(&SHA256, &other.0).as_ref().into();
        h1.cmp(&(h2))
    }
}

impl PartialOrd for Data {
    fn partial_cmp(&self, other: &Data) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl PartialEq for Data {
    fn eq(&self, other: &Data) -> bool {
        self.cmp(other) == Ordering::Equal
    }
}

/// ref. https://rust-lang.github.io/rust-clippy/master/index.html#derive_hash_xor_eq
impl Hash for Data {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.0.hash(state);
    }
}

/// Represents a slice of raw transaction bytes, to be sorted
/// in the order of SHA256 hash digests.
#[derive(Eq)]
pub struct DataSlice(Vec<Data>);

impl DataSlice {
    pub fn new(txs: &[Data]) -> Self {
        DataSlice(Vec::from(txs))
    }
}

impl Ord for DataSlice {
    fn cmp(&self, other: &DataSlice) -> Ordering {
        self.0.cmp(&other.0)
    }
}

impl PartialOrd for DataSlice {
    fn partial_cmp(&self, other: &DataSlice) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl PartialEq for DataSlice {
    fn eq(&self, other: &DataSlice) -> bool {
        self.cmp(other) == Ordering::Equal
    }
}

/// RUST_LOG=debug cargo test --package avalanche-types --lib -- raw_tx::test_sort --exact --show-output
#[test]
fn test_sort() {
    let d1 = <Vec<u8>>::from([0x01, 0x00, 0x00, 0x00]);
    let d2 = <Vec<u8>>::from([0x01, 0x00, 0x00, 0x00]);
    assert!(d1 == d2);

    let d1 = <Vec<u8>>::from([0x01, 0x00, 0x00, 0x00]);
    let d2 = <Vec<u8>>::from([0x01, 0x00, 0x00, 0x00, 0x00]);
    assert!(d1 < d2);

    let d1 = Data(<Vec<u8>>::from([0x01, 0x00, 0x00, 0x00]));
    let d2 = Data(<Vec<u8>>::from([0x01, 0x00, 0x00, 0x00, 0x00]));
    assert!(d1 < d2);

    let d1 = Data(<Vec<u8>>::from([0x99, 0x00, 0x00, 0x00]));
    let d2 = Data(<Vec<u8>>::from([0x99, 0x00, 0x00, 0x00, 0x00]));
    assert!(d1 < d2);

    let d1 = Data(<Vec<u8>>::from([0x99, 0x00, 0x00]));
    let d2 = Data(<Vec<u8>>::from([0x99, 0x00, 0x01]));
    assert!(d1 < d2);

    let d1 = Data(<Vec<u8>>::from([0x99, 0x01, 0x01]));
    let d2 = Data(<Vec<u8>>::from([0x99, 0x20, 0x01]));
    assert!(d1 > d2);

    let d1 = Data(<Vec<u8>>::from([0x01]));
    let d2 = Data(<Vec<u8>>::from([0x02]));
    let d3 = Data(<Vec<u8>>::from([0x03]));
    assert!(d1 < d2);
    assert!(d2 > d3);
    assert!(d1 > d3);

    let mut ds1 = DataSlice(vec![
        Data(<Vec<u8>>::from([0x01])),
        Data(<Vec<u8>>::from([0x02])),
        Data(<Vec<u8>>::from([0x03])),
    ]);
    ds1.0.sort();
    let ds2 = DataSlice(vec![
        Data(<Vec<u8>>::from([0x03])),
        Data(<Vec<u8>>::from([0x01])),
        Data(<Vec<u8>>::from([0x02])),
    ]);
    assert!(ds1 == ds2);

    let mut ds1 = vec![
        Data(<Vec<u8>>::from([0x01])),
        Data(<Vec<u8>>::from([0x02])),
        Data(<Vec<u8>>::from([0x03])),
    ];
    ds1.sort();
    let ds2 = vec![
        Data(<Vec<u8>>::from([0x03])),
        Data(<Vec<u8>>::from([0x01])),
        Data(<Vec<u8>>::from([0x02])),
    ];
    assert!(ds1 == ds2);

    let mut ds1 = vec![
        <Vec<u8>>::from([0x01]),
        <Vec<u8>>::from([0x02]),
        <Vec<u8>>::from([0x03]),
    ];
    ds1.sort_by(|a, b| (Data::from_slice(a.as_ref())).cmp(&Data::from_slice(b.as_ref())));
    let ds2 = vec![
        <Vec<u8>>::from([0x03]),
        <Vec<u8>>::from([0x01]),
        <Vec<u8>>::from([0x02]),
    ];
    assert!(ds1 == ds2);
}