serde-diff 0.2.0

A small helper to serialize the diff of two structs of the same type and apply those differences to other structs.
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

use super::*;
use std::fmt::Debug;

#[derive(SerdeDiff, Serialize, Deserialize, PartialEq, Debug, Copy, Clone)]
struct TestStruct {
    a: u32,
    b: f64,
}

fn roundtrip<T: SerdeDiff + Serialize + for<'a> Deserialize<'a> + PartialEq + Debug + Clone>(
    old: T,
    new: T,
) {
    let diff = Diff::serializable(&old, &new);
    let json_diff = serde_json::to_string(&diff).unwrap();
    let mut deserializer = serde_json::Deserializer::from_str(&json_diff);
    let mut target = old.clone();
    Apply::apply(&mut deserializer, &mut target).unwrap();
    assert_eq!(target, new);

    let bincode_diff = bincode::serialize(&diff).unwrap();
    let mut target = old;
    bincode::config()
        .deserialize_seed(Apply::deserializable(&mut target), &bincode_diff)
        .unwrap();
    assert_eq!(target, new);
}

fn partial<T: SerdeDiff + Serialize + for<'a> Deserialize<'a> + PartialEq + Debug + Clone>(
    old: T,
    new: T,
    target: T,
    expected: T,
) {
    let diff = Diff::serializable(&old, &new);
    let json_diff = serde_json::to_string(&diff).unwrap();
    let mut deserializer = serde_json::Deserializer::from_str(&json_diff);
    let mut tmp_target = target.clone();
    Apply::apply(&mut deserializer, &mut tmp_target).unwrap();
    assert_eq!(tmp_target, expected);

    let bincode_diff = bincode::serialize(&diff).unwrap();
    let mut tmp_target = target;
    bincode::config()
        .deserialize_seed(Apply::deserializable(&mut tmp_target), &bincode_diff)
        .unwrap();
    assert_eq!(tmp_target, expected);
}

#[test]
fn test_option() {
    roundtrip(None::<TestStruct>, None);
    roundtrip(None, Some(TestStruct { a: 42, b: 12. }));
    roundtrip(Some(TestStruct { a: 42, b: 12. }), None);
    roundtrip(
        Some(TestStruct { a: 52, b: 32. }),
        Some(TestStruct { a: 42, b: 12. }),
    );

    partial(
        Some(TestStruct { a: 5, b: 2. }),
        Some(TestStruct { a: 8, b: 2. }),
        Some(TestStruct { a: 0, b: 4. }),
        Some(TestStruct { a: 8, b: 4. }),
    );
}

#[test]
fn test_array() {
    partial([0, 1, 2, 3], [0, 1, 9, 3], [4, 5, 6, 7], [4, 5, 9, 7]);

    partial(
        Some([0, 1, 2, 3]),
        Some([0, 1, 9, 3]),
        Some([4, 5, 6, 7]),
        Some([4, 5, 9, 7]),
    );

    partial(
        [
            None,
            Some(TestStruct { a: 5, b: 2. }),
            Some(TestStruct { a: 5, b: 2. }),
        ],
        [
            Some(TestStruct { a: 8, b: 2. }),
            Some(TestStruct { a: 8, b: 2. }),
            None,
        ],
        [None, Some(TestStruct { a: 0, b: 4. }), None],
        [
            Some(TestStruct { a: 8, b: 2. }),
            Some(TestStruct { a: 8, b: 4. }),
            None,
        ],
    );
}

#[test]
fn test_tuple() {
    roundtrip(
        (None::<TestStruct>, Some(TestStruct { a: 8, b: 2. })),
        (None, Some(TestStruct { a: 8, b: 2. })),
    );

    partial((0, 1, 2, 3), (0, 1, 9, 3), (4, 5, 6, 7), (4, 5, 9, 7));

    partial(
        Some((0, 1, 2, 3)),
        Some((0, 1, 9, 3)),
        Some((4, 5, 6, 7)),
        Some((4, 5, 9, 7)),
    );

    partial(
        (
            None,
            Some(TestStruct { a: 5, b: 2. }),
            Some(TestStruct { a: 5, b: 2. }),
        ),
        (
            Some(TestStruct { a: 8, b: 2. }),
            Some(TestStruct { a: 8, b: 2. }),
            None,
        ),
        (None, Some(TestStruct { a: 0, b: 4. }), None),
        (
            Some(TestStruct { a: 8, b: 2. }),
            Some(TestStruct { a: 8, b: 4. }),
            None,
        ),
    );
}