60 lines
1.4 KiB
Rust
60 lines
1.4 KiB
Rust
|
use hex;
|
||
|
|
use hex::ToHex;
|
||
|
|
use serde::de::{self, Visitor};
|
||
|
|
use std::fmt;
|
||
|
|
|
||
|
|
pub fn encode<T: AsRef<[u8]>>(data: T) -> String {
|
||
|
|
let mut hex = String::with_capacity(data.as_ref().len() * 2);
|
||
|
|
|
||
|
|
// Writing to a string never errors, so we can unwrap here.
|
||
|
|
data.write_hex(&mut hex).unwrap();
|
||
|
|
|
||
|
|
let mut s = "0x".to_string();
|
||
|
|
|
||
|
|
s.push_str(hex.as_str());
|
||
|
|
|
||
|
|
s
|
||
|
|
}
|
||
|
|
|
||
|
|
pub struct PrefixedHexVisitor;
|
||
|
|
|
||
|
|
impl<'de> Visitor<'de> for PrefixedHexVisitor {
|
||
|
|
type Value = Vec<u8>;
|
||
|
|
|
||
|
|
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
|
||
|
|
formatter.write_str("a hex string with 0x prefix")
|
||
|
|
}
|
||
|
|
|
||
|
|
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
|
||
|
|
where
|
||
|
|
E: de::Error,
|
||
|
|
{
|
||
|
|
if value.starts_with("0x") {
|
||
|
|
Ok(hex::decode(&value[2..])
|
||
|
|
.map_err(|e| de::Error::custom(format!("invalid hex ({:?})", e)))?)
|
||
|
|
} else {
|
||
|
|
Err(de::Error::custom("missing 0x prefix"))
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#[cfg(test)]
|
||
|
|
mod test {
|
||
|
|
use super::*;
|
||
|
|
|
||
|
|
#[test]
|
||
|
|
fn encoding() {
|
||
|
|
let bytes = vec![0, 255];
|
||
|
|
let hex = encode(&bytes);
|
||
|
|
assert_eq!(hex.as_str(), "0x00ff");
|
||
|
|
|
||
|
|
let bytes = vec![];
|
||
|
|
let hex = encode(&bytes);
|
||
|
|
assert_eq!(hex.as_str(), "0x");
|
||
|
|
|
||
|
|
let bytes = vec![1, 2, 3];
|
||
|
|
let hex = encode(&bytes);
|
||
|
|
assert_eq!(hex.as_str(), "0x010203");
|
||
|
|
}
|
||
|
|
}
|