hex/
error.rs

1use core::fmt;
2
3/// The error type for decoding a hex string into `Vec<u8>` or `[u8; N]`.
4#[derive(Debug, Clone, Copy, PartialEq)]
5pub enum FromHexError {
6    /// An invalid character was found. Valid ones are: `0...9`, `a...f`
7    /// or `A...F`.
8    InvalidHexCharacter { c: char, index: usize },
9
10    /// A hex string's length needs to be even, as two digits correspond to
11    /// one byte.
12    OddLength,
13
14    /// If the hex string is decoded into a fixed sized container, such as an
15    /// array, the hex string's length * 2 has to match the container's
16    /// length.
17    InvalidStringLength,
18}
19
20#[cfg(feature = "std")]
21impl std::error::Error for FromHexError {}
22
23impl fmt::Display for FromHexError {
24    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
25        match *self {
26            FromHexError::InvalidHexCharacter { c, index } => {
27                write!(f, "Invalid character {:?} at position {}", c, index)
28            }
29            FromHexError::OddLength => write!(f, "Odd number of digits"),
30            FromHexError::InvalidStringLength => write!(f, "Invalid string length"),
31        }
32    }
33}
34
35#[cfg(test)]
36// this feature flag is here to suppress unused
37// warnings of `super::*` and `pretty_assertions::assert_eq`
38#[cfg(feature = "alloc")]
39mod tests {
40    use super::*;
41    #[cfg(feature = "alloc")]
42    use alloc::string::ToString;
43    use pretty_assertions::assert_eq;
44
45    #[test]
46    #[cfg(feature = "alloc")]
47    fn test_display() {
48        assert_eq!(
49            FromHexError::InvalidHexCharacter { c: '\n', index: 5 }.to_string(),
50            "Invalid character '\\n' at position 5"
51        );
52
53        assert_eq!(FromHexError::OddLength.to_string(), "Odd number of digits");
54        assert_eq!(
55            FromHexError::InvalidStringLength.to_string(),
56            "Invalid string length"
57        );
58    }
59}
hex/error.rs

hex/
error.rs
