codeq 0.5.2

Codec trait
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

use std::ops::Add;
use std::ops::AddAssign;
use std::ops::Deref;
use std::ops::Sub;
use std::ops::SubAssign;

use derive_more::Display;
use derive_more::From;

use crate::span::Size;

/// Represents a byte position/offset in a file or buffer.
///
/// This type wraps a `u64` to provide type safety and prevent accidental mixing
/// of offsets with other numeric values. It supports:
/// - Addition and subtraction with `Size`
/// - Comparison with other offsets
/// - Conversion from `u64`
///
/// # Examples
/// ```rust
/// use codeq::{Offset, Size};
///
/// let offset = Offset(1000);
///
/// // Add or subtract sizes
/// let advanced = offset + Size(50);
/// assert_eq!(advanced, Offset(1050));
///
/// // Calculate distance between offsets
/// let size: Size = Offset(100) - Offset(50);
/// assert_eq!(size, Size(50));
///
/// // Offsets can be compared
/// assert!(Offset(100) > Offset(50));
/// ```
#[derive(Debug, Clone, Copy, Default)]
#[derive(PartialEq, Eq, PartialOrd, Ord)]
#[derive(From)]
#[derive(Display)]
#[display("Offset({_0})")]
pub struct Offset(pub u64);

impl Add<Size> for Offset {
    type Output = Offset;

    fn add(self, rhs: Size) -> Self::Output {
        Offset(*self + *rhs)
    }
}

impl AddAssign<Size> for Offset {
    fn add_assign(&mut self, rhs: Size) {
        *self = Offset(self.0 + *rhs);
    }
}

impl Sub<Size> for Offset {
    type Output = Offset;

    fn sub(self, rhs: Size) -> Self::Output {
        Offset(*self - *rhs)
    }
}

impl SubAssign<Size> for Offset {
    fn sub_assign(&mut self, rhs: Size) {
        *self = Offset(self.0 - *rhs);
    }
}

impl Sub for Offset {
    type Output = Size;

    fn sub(self, rhs: Self) -> Self::Output {
        Size(*self - *rhs)
    }
}

impl Deref for Offset {
    type Target = u64;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

#[cfg(test)]
mod tests {
    use super::Offset;
    use crate::span::Size;

    #[test]
    fn test_display() {
        assert_eq!(format!("{:?}", Offset(42)), "Offset(42)");
        assert_eq!(format!("{}", Offset(42)), "Offset(42)");
    }

    #[allow(clippy::clone_on_copy)]
    #[test]
    fn test_calculation() {
        let mut a = Offset(42);
        let b = Offset(10);

        // Add Sub

        assert_eq!(a + Size(3), Offset(45));
        assert_eq!(a - Size(3), Offset(39));

        a += Size(3);
        assert_eq!(a, Offset(45));
        a -= Size(3);
        assert_eq!(a, Offset(42));

        // Eq, Ord

        assert_eq!(a, Offset(42));
        assert!(a > b);

        // From

        let c = Offset::from(1u64);

        // Clone Copy

        let d = c.clone();
        assert_eq!(d, c);

        let d = c;
        assert_eq!(d, c);

        // Default

        assert_eq!(Offset::default(), Offset(0));

        // Deref

        assert_eq!(*Offset(1u64), 1u64);
    }
}