git_prole/git/
commit_hash.rs

1use std::fmt::Display;
2use std::str::FromStr;
3
4use derive_more::{AsRef, Constructor, Deref, DerefMut, From, Into};
5use miette::miette;
6use winnow::combinator::repeat;
7use winnow::token::one_of;
8use winnow::PResult;
9use winnow::Parser;
10
11/// A Git commit hash.
12#[derive(
13    Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Into, AsRef, Deref, DerefMut, Constructor,
14)]
15pub struct CommitHash(String);
16
17impl CommitHash {
18    /// A fake commit hash for testing purposes.
19    #[cfg(test)]
20    pub fn fake() -> Self {
21        Self("a".repeat(40))
22    }
23
24    /// Get an abbreviated 8-character Git hash.
25    pub fn abbrev(&self) -> &str {
26        &self.0[..8]
27    }
28
29    pub fn parser(input: &mut &str) -> PResult<Self> {
30        Ok(Self::from(
31            repeat(40, one_of(('0'..='9', 'a'..='f')))
32                .map(|()| ())
33                .take()
34                .parse_next(input)?,
35        ))
36    }
37}
38
39impl Display for CommitHash {
40    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
41        if f.alternate() {
42            Display::fmt(&self.0, f)
43        } else {
44            Display::fmt(self.abbrev(), f)
45        }
46    }
47}
48
49impl<S> From<S> for CommitHash
50where
51    S: AsRef<str>,
52{
53    fn from(value: S) -> Self {
54        Self(value.as_ref().into())
55    }
56}
57
58impl FromStr for CommitHash {
59    type Err = miette::Report;
60
61    fn from_str(s: &str) -> Result<Self, Self::Err> {
62        Self::parser.parse(s).map_err(|err| miette!("{err}"))
63    }
64}
65
66#[cfg(test)]
67mod tests {
68    use super::*;
69
70    #[test]
71    fn test_parse_commit_hash() {
72        assert_eq!(
73            CommitHash::from_str("1233def1234def1234def1234def1234def1234b").unwrap(),
74            CommitHash::new("1233def1234def1234def1234def1234def1234b".into()),
75        );
76
77        // Too short
78        assert!(CommitHash::from_str("1233def1234def1234def1234def1234def1234").is_err());
79
80        // Too long
81        assert!(CommitHash::from_str("1233def1234def1234def1234def1234def1234ab").is_err());
82
83        // Uppercase not allowed
84        assert!(CommitHash::from_str("1233DEF1234DEF1234DEF1234DEF1234DEF1234B").is_err());
85
86        // Illegal character
87        assert!(CommitHash::from_str("1233def1234def1234gef1234def1234def1234b").is_err());
88    }
89}
git_prole/git/commit_hash.rs

git_prole/git/
commit_hash.rs
