caj2pdf-core 0.5.0

Platform-neutral CAJ-family conversion core
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

// SPDX-License-Identifier: MIT

use super::{
    checked_read_count, len_u64, push_bounded, reserve, reserve_exact, try_convert, usize_from_u32,
};
use crate::Error;
use crate::ErrorKind;

#[test]
fn length_conversion_is_lossless() {
    assert_eq!(len_u64(0), 0);
    assert_eq!(len_u64(usize::MAX), usize::MAX as u64);
    assert_eq!(usize_from_u32(0), 0);
    assert_eq!(usize_from_u32(u32::MAX), u32::MAX as usize);
}

#[test]
fn conversions_return_the_supplied_error_when_out_of_range() {
    assert_eq!(try_convert::<u8, _, _>(255_u32, "unused"), Ok(255_u8));
    assert_eq!(try_convert::<u8, _, _>(256_u32, "range"), Err("range"));
    assert_eq!(try_convert::<u32, _, _>(u64::MAX, "range"), Err("range"));
}

#[test]
fn read_counts_may_not_exceed_the_request() {
    assert!(matches!(checked_read_count(0, 0, "unused"), Ok(0)));
    assert!(matches!(checked_read_count(4, 4, "unused"), Ok(4)));
    assert!(matches!(
        checked_read_count(5, 4, "overread"),
        Err(Error {
            kind: ErrorKind::Malformed,
            reason: "overread",
            ..
        })
    ));
}

#[test]
fn reservations_succeed_within_capacity() {
    let mut values = Vec::<u8>::new();
    assert_eq!(reserve_exact(&mut values, 3, "unused"), Ok(()));
    assert!(values.capacity() >= 3);
    assert_eq!(reserve(&mut values, 8, "unused"), Ok(()));
    assert!(values.capacity() >= 8);
}

#[test]
fn reservation_failures_return_the_supplied_error() {
    // A request beyond `isize::MAX` bytes fails as a capacity overflow without
    // asking the allocator, which models an allocator refusal deterministically.
    let mut values = Vec::<u64>::new();
    assert_eq!(
        reserve_exact(&mut values, usize::MAX, "exact"),
        Err("exact")
    );
    assert_eq!(
        reserve(&mut values, usize::MAX, "amortized"),
        Err("amortized")
    );
    assert!(values.is_empty());
}

#[test]
fn bounded_index_growth_reports_the_attempted_capacity() {
    let mut items: Vec<u64> = Vec::new();
    assert!(matches!(
        push_bounded(&mut items, 1, 16, "test index"),
        Err(Error {
            kind: ErrorKind::LimitExceeded {
                resource: "test index",
                limit: 16,
                attempted: 32,
                ..
            },
            ..
        })
    ));
    assert!(items.is_empty());
    for value in 0..8 {
        push_bounded(&mut items, value, 64, "test index").unwrap();
    }
    assert_eq!(items, [0, 1, 2, 3, 4, 5, 6, 7]);
    assert!(matches!(
        push_bounded(&mut items, 8, 64, "test index"),
        Err(Error {
            kind: ErrorKind::LimitExceeded { attempted: 128, .. },
            ..
        })
    ));
    assert_eq!(items.len(), 8);
}