ps_uuid/methods/
with_variant.rs

1use crate::{Variant, UUID};
2
3impl UUID {
4    #[must_use]
5    pub const fn with_variant(self, variant: Variant) -> Self {
6        let mut uuid = self;
7
8        uuid.bytes[8] &= variant.bitmask();
9        uuid.bytes[8] |= variant.prefix();
10
11        uuid
12    }
13}
14
15#[cfg(test)]
16mod tests {
17    use super::{Variant, UUID};
18
19    const fn make_uuid_with_byte_8(byte: u8) -> UUID {
20        let mut bytes = [0u8; 16];
21        bytes[8] = byte;
22        UUID { bytes }
23    }
24
25    #[test]
26    fn with_variant_ncs() {
27        let uuid = make_uuid_with_byte_8(0xFF);
28        let result = uuid.with_variant(Variant::NCS);
29        assert_eq!(result.get_variant(), Variant::NCS);
30        assert_eq!(result.bytes[8] & 0x80, 0x00);
31    }
32
33    #[test]
34    fn with_variant_osf() {
35        let uuid = make_uuid_with_byte_8(0x00);
36        let result = uuid.with_variant(Variant::OSF);
37        assert_eq!(result.get_variant(), Variant::OSF);
38        assert_eq!(result.bytes[8] & 0xC0, 0x80);
39    }
40
41    #[test]
42    fn with_variant_dcom() {
43        let uuid = make_uuid_with_byte_8(0x3F);
44        let result = uuid.with_variant(Variant::DCOM);
45        assert_eq!(result.get_variant(), Variant::DCOM);
46        assert_eq!(result.bytes[8] & 0xE0, 0xC0);
47    }
48
49    #[test]
50    fn with_variant_reserved() {
51        let uuid = make_uuid_with_byte_8(0x00);
52        let result = uuid.with_variant(Variant::Reserved);
53        assert_eq!(result.get_variant(), Variant::Reserved);
54        assert_eq!(result.bytes[8] & 0xE0, 0xE0);
55    }
56
57    #[test]
58    fn with_variant_preserves_other_bytes() {
59        let original_bytes = [1, 2, 3, 4, 5, 6, 7, 8, 0xFF, 10, 11, 12, 13, 14, 15, 16];
60        let uuid = UUID {
61            bytes: original_bytes,
62        };
63
64        let result = uuid.with_variant(Variant::OSF);
65
66        for (i, &byte) in result.bytes.iter().enumerate() {
67            if i != 8 {
68                assert_eq!(byte, original_bytes[i]);
69            }
70        }
71    }
72
73    #[test]
74    fn with_variant_leaves_original_unchanged() {
75        let original_bytes = [1, 2, 3, 4, 5, 6, 7, 8, 0xFF, 10, 11, 12, 13, 14, 15, 16];
76        let uuid = UUID {
77            bytes: original_bytes,
78        };
79
80        let _result = uuid.with_variant(Variant::OSF);
81
82        assert_eq!(uuid.bytes, original_bytes);
83    }
84
85    #[test]
86    fn with_variant_can_chain_variants() {
87        let uuid = make_uuid_with_byte_8(0x00);
88
89        let result = uuid
90            .with_variant(Variant::NCS)
91            .with_variant(Variant::OSF)
92            .with_variant(Variant::DCOM)
93            .with_variant(Variant::Reserved);
94
95        assert_eq!(result.get_variant(), Variant::Reserved);
96    }
97
98    #[test]
99    fn with_variant_idempotent() {
100        let uuid = make_uuid_with_byte_8(0xA5);
101
102        let first_result = uuid.with_variant(Variant::OSF);
103        let second_result = first_result.with_variant(Variant::OSF);
104
105        assert_eq!(first_result.bytes[8], second_result.bytes[8]);
106    }
107}
ps_uuid/methods/with_variant.rs

ps_uuid/methods/
with_variant.rs
