ethnum/uint/
parse.rs

1//! Module implementing parsing for `U256` type.
2
3use crate::uint::U256;
4
5impl_from_str! {
6    impl FromStr for U256;
7}
8
9pub const fn const_from_str_prefixed(src: &str) -> U256 {
10    assert!(!src.is_empty(), "empty string");
11
12    let bytes = src.as_bytes();
13    let start = bytes[0] == b'+';
14    crate::parse::const_from_str_prefixed(bytes, start as _)
15}
16
17#[cfg(test)]
18mod tests {
19    use super::*;
20    use crate::parse::from_str_radix;
21    use core::num::IntErrorKind;
22
23    #[test]
24    fn from_str() {
25        assert_eq!("42".parse::<U256>().unwrap(), 42);
26    }
27
28    #[test]
29    fn from_str_prefixed() {
30        assert_eq!(from_str_radix::<U256>("0b101", 2, Some("0b")).unwrap(), 5);
31        assert_eq!(from_str_radix::<U256>("0xf", 16, Some("0x")).unwrap(), 15);
32    }
33
34    #[test]
35    fn from_str_errors() {
36        assert_eq!(
37            from_str_radix::<U256>("", 2, None).unwrap_err().kind(),
38            &IntErrorKind::Empty,
39        );
40        assert_eq!(
41            from_str_radix::<U256>("?", 2, None).unwrap_err().kind(),
42            &IntErrorKind::InvalidDigit,
43        );
44        assert_eq!(
45            from_str_radix::<U256>("1", 16, Some("0x"))
46                .unwrap_err()
47                .kind(),
48            &IntErrorKind::InvalidDigit,
49        );
50        assert_eq!(
51            from_str_radix::<U256>("-1", 10, None).unwrap_err().kind(),
52            &IntErrorKind::InvalidDigit,
53        );
54        assert_eq!(
55            from_str_radix::<U256>(
56                "zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz",
57                36,
58                None
59            )
60            .unwrap_err()
61            .kind(),
62            &IntErrorKind::PosOverflow,
63        );
64    }
65
66    #[test]
67    fn const_parse() {
68        assert_eq!(const_from_str_prefixed("+0b1101"), 0b1101);
69        assert_eq!(const_from_str_prefixed("0o777"), 0o777);
70        assert_eq!(const_from_str_prefixed("+0x1f"), 0x1f);
71        assert_eq!(const_from_str_prefixed("42"), 42);
72
73        assert_eq!(
74            const_from_str_prefixed(
75                "0xffff_ffff_ffff_ffff_ffff_ffff_ffff_fffe\
76                   baae_dce6_af48_a03b_bfd2_5e8c_d036_4141"
77            ),
78            U256::from_words(
79                0xffff_ffff_ffff_ffff_ffff_ffff_ffff_fffe,
80                0xbaae_dce6_af48_a03b_bfd2_5e8c_d036_4141,
81            ),
82        );
83
84        assert_eq!(
85            const_from_str_prefixed(
86                "0x0000_0000_0000_0000_0000_0000_0000_0000\
87                   0000_0000_0000_0000_0000_0000_0000_0000"
88            ),
89            U256::MIN,
90        );
91        assert_eq!(
92            const_from_str_prefixed(
93                "+0xffff_ffff_ffff_ffff_ffff_ffff_ffff_ffff\
94                    ffff_ffff_ffff_ffff_ffff_ffff_ffff_ffff"
95            ),
96            U256::MAX,
97        );
98    }
99
100    #[test]
101    #[should_panic]
102    fn const_parse_overflow() {
103        const_from_str_prefixed(
104            "0x1\
105               0000_0000_0000_0000_0000_0000_0000_0000\
106               0000_0000_0000_0000_0000_0000_0000_0000",
107        );
108    }
109
110    #[test]
111    #[should_panic]
112    fn const_parse_invalid() {
113        const_from_str_prefixed("invalid");
114    }
115}
ethnum/uint/parse.rs

ethnum/uint/
parse.rs
