deku 0.20.3

bit level serialization/deserialization proc-macro for 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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156

#![cfg(feature = "std")]

use deku::{noseek::NoSeek, prelude::*};
use hexlit::hex;
use rstest::*;

#[derive(DekuRead, DekuWrite, Debug, PartialEq, Eq)]
pub struct Test {
    // how many following bytes to skip
    skip_u8: u8,
    #[deku(seek_from_current = "*skip_u8")]
    byte: u8,
    #[deku(seek_from_current = "0")]
    byte_after: u8,
    #[deku(seek_rewind)]
    byte_after_rewind: u8,
    #[deku(seek_from_start = "2")]
    byte_again: u8,
    #[deku(seek_from_end = "-1")]
    another: u8,
}

#[rstest(input, expected,
    case(&hex!("01002030"), Test{ skip_u8: 1, byte: 0x20, byte_after: 0x30, byte_after_rewind: 0x01, byte_again: 0x20, another: 0x30 }),
    case(&hex!("0200002030"), Test{ skip_u8: 2, byte: 0x20, byte_after: 0x30, byte_after_rewind: 0x02, byte_again: 0x00, another: 0x30 }),
    case(&hex!("00ffaa"), Test{ skip_u8: 0, byte: 0xff, byte_after: 0xaa, byte_after_rewind: 0x00, byte_again: 0xaa, another: 0xaa }),
)]
#[cfg(feature = "alloc")]
fn test_seek(input: &[u8], expected: Test) {
    let input = input.to_vec();
    let mut cursor = std::io::Cursor::new(input.clone());
    let (_, ret_read) = Test::from_reader((&mut cursor, 0)).unwrap();

    assert_eq!(ret_read, expected);

    let bytes = ret_read.to_bytes().unwrap();
    assert_eq!(bytes, input);
}

#[derive(DekuRead, DekuWrite, Debug, PartialEq, Eq)]
#[deku(seek_from_current = "skip", ctx = "skip: usize")]
pub struct SeekCtxBefore {
    byte: u8,
}

#[rstest(input, ctx, expected,
    case(&hex!("0003"), 1, SeekCtxBefore{ byte: 0x03 }),
    case(&hex!("000004"), 2, SeekCtxBefore{ byte: 0x04 }),
)]
#[cfg(feature = "std")]
fn test_seek_ctx_before(input: &[u8], ctx: usize, expected: SeekCtxBefore) {
    use std::io::Cursor;
    let input = input.to_vec();

    let mut cursor = std::io::Cursor::new(input.clone());
    let mut reader = Reader::new(&mut cursor);
    let ret_read = SeekCtxBefore::from_reader_with_ctx(&mut reader, ctx).unwrap();

    assert_eq!(ret_read, expected);

    let mut buf = vec![];
    let mut cursor = Cursor::new(&mut buf);
    let mut writer = Writer::new(&mut cursor);
    ret_read.to_writer(&mut writer, ctx).unwrap();
    assert_eq!(buf, input);
}

#[derive(DekuRead, DekuWrite, Debug, PartialEq, Eq)]
#[deku(seek_from_start = "1")]
pub struct SeekCtxBeforeStart {
    byte: u8,
}

#[rstest(input, expected,
    case(&hex!("0003"), SeekCtxBeforeStart{ byte: 0x03 }),
    case(&hex!("00ff"), SeekCtxBeforeStart{ byte: 0xff }),
)]
#[cfg(feature = "std")]
fn test_seek_ctx_start(input: &[u8], expected: SeekCtxBeforeStart) {
    use std::io::Cursor;
    let input = input.to_vec();

    let mut cursor = std::io::Cursor::new(input.clone());
    let mut reader = Reader::new(&mut cursor);
    let ret_read = SeekCtxBeforeStart::from_reader_with_ctx(&mut reader, ()).unwrap();

    assert_eq!(ret_read, expected);

    let mut buf = vec![];
    let mut cursor = Cursor::new(&mut buf);
    let mut writer = Writer::new(&mut cursor);
    ret_read.to_writer(&mut writer, ()).unwrap();
    assert_eq!(buf, input);
}

#[derive(DekuRead, DekuWrite, Debug, PartialEq, Eq)]
#[deku(seek_from_end = "-2")]
pub struct SeekCtxBeforeEnd {
    byte: u8,
}

#[rstest(input, expected,
    case(&hex!("000300"), SeekCtxBeforeEnd{ byte: 0x03 }),
    case(&hex!("00ff00"), SeekCtxBeforeEnd{ byte: 0xff }),
)]
#[cfg(feature = "std")]
fn test_seek_ctx_end(input: &[u8], expected: SeekCtxBeforeEnd) {
    use std::io::Cursor;
    let input = input.to_vec();

    let mut cursor = std::io::Cursor::new(input.clone());
    let mut reader = Reader::new(&mut cursor);
    let ret_read = SeekCtxBeforeEnd::from_reader_with_ctx(&mut reader, ()).unwrap();

    assert_eq!(ret_read, expected);

    let mut buf = vec![0, 0, 0];
    let mut cursor = Cursor::new(&mut buf);
    let mut writer = Writer::new(&mut cursor);
    ret_read.to_writer(&mut writer, ()).unwrap();
    assert_eq!(buf, input);
}

#[derive(DekuRead, DekuWrite, Debug, PartialEq, Eq)]
#[deku(seek_from_start = "0")]
pub struct SeekCtxNoSeek {
    byte: u8,
}

#[rstest(input, expected,
    case(&hex!("03"), SeekCtxNoSeek { byte: 0x03 }),
    case(&hex!("ff"), SeekCtxNoSeek { byte: 0xff }),
)]
#[cfg(feature = "std")]
fn test_seek_ctx_no_seek(input: &[u8], expected: SeekCtxNoSeek) {
    use std::io::Cursor;
    let input = input.to_vec();

    let mut cursor = std::io::Cursor::new(input.clone());
    let mut reader = Reader::new(&mut cursor);
    let ret_read = SeekCtxNoSeek::from_reader_with_ctx(&mut reader, ()).unwrap();

    assert_eq!(ret_read, expected);

    let mut buf = vec![];
    let mut cursor = Cursor::new(&mut buf);
    let mut writer = Writer::new(&mut cursor);
    ret_read.to_writer(&mut writer, ()).unwrap();
    assert_eq!(buf, input);

    let mut buf = vec![];
    let mut cursor = NoSeek::new(&mut buf);
    let mut writer = Writer::new(&mut cursor);
    ret_read.to_writer(&mut writer, ()).unwrap();
    assert_eq!(buf, input);
}