uv/crates/uv-git/src/sha.rs

131 lines
3.1 KiB
Rust

use std::fmt::Display;
use std::str::{self, FromStr};
use thiserror::Error;
/// A complete Git SHA, i.e., a 40-character hexadecimal representation of a Git commit.
#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct GitSha(GitOid);
impl GitSha {
/// Convert the SHA to a truncated representation, i.e., the first 16 characters of the SHA.
pub fn to_short_string(&self) -> String {
self.0.to_string()[0..16].to_string()
}
}
impl From<GitSha> for GitOid {
fn from(value: GitSha) -> Self {
value.0
}
}
impl From<GitOid> for GitSha {
fn from(value: GitOid) -> Self {
Self(value)
}
}
impl Display for GitSha {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.0)
}
}
impl FromStr for GitSha {
type Err = OidParseError;
fn from_str(value: &str) -> Result<Self, Self::Err> {
Ok(Self(GitOid::from_str(value)?))
}
}
impl serde::Serialize for GitSha {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
self.0.as_str().serialize(serializer)
}
}
impl<'de> serde::Deserialize<'de> for GitSha {
fn deserialize<D>(deserializer: D) -> Result<GitSha, D::Error>
where
D: serde::Deserializer<'de>,
{
let value = String::deserialize(deserializer)?;
GitSha::from_str(&value).map_err(serde::de::Error::custom)
}
}
/// Unique identity of any Git object (commit, tree, blob, tag).
///
/// Note this type does not validate whether the input is a valid hash.
#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct GitOid {
len: usize,
bytes: [u8; 40],
}
impl GitOid {
/// Return the string representation of an object ID.
pub(crate) fn as_str(&self) -> &str {
str::from_utf8(&self.bytes[..self.len]).unwrap()
}
}
#[derive(Debug, Error, PartialEq)]
pub enum OidParseError {
#[error("Object ID can be at most 40 hex characters")]
TooLong,
#[error("Object ID cannot be parsed from empty string")]
Empty,
}
impl FromStr for GitOid {
type Err = OidParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if s.is_empty() {
return Err(OidParseError::Empty);
}
if s.len() > 40 {
return Err(OidParseError::TooLong);
}
let mut out = [0; 40];
out[..s.len()].copy_from_slice(s.as_bytes());
Ok(GitOid {
len: s.len(),
bytes: out,
})
}
}
impl Display for GitOid {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.as_str())
}
}
#[cfg(test)]
mod tests {
use std::str::FromStr;
use super::{GitOid, OidParseError};
#[test]
fn git_oid() {
GitOid::from_str("4a23745badf5bf5ef7928f1e346e9986bd696d82").unwrap();
assert_eq!(GitOid::from_str(""), Err(OidParseError::Empty));
assert_eq!(
GitOid::from_str(&str::repeat("a", 41)),
Err(OidParseError::TooLong)
);
}
}