git_ark/
clock.rs

1pub trait Clock {
2    fn timestamp(&self) -> String;
3}
4
5pub struct SystemClock;
6
7impl Clock for SystemClock {
8    fn timestamp(&self) -> String {
9        use time::format_description::FormatItem;
10        use time::macros::format_description;
11        const FMT: &[FormatItem] =
12            format_description!("[year]-[month]-[day]T[hour]-[minute]-[second]Z");
13        time::OffsetDateTime::now_utc()
14            .format(&FMT)
15            .expect("format utc timestamp")
16    }
17}
18
19pub struct FixedClock(pub String);
20
21impl Clock for FixedClock {
22    fn timestamp(&self) -> String {
23        self.0.clone()
24    }
25}
26
27#[cfg(test)]
28mod tests {
29    use super::*;
30    #[test]
31    fn fixed_clock_returns_its_value() {
32        assert_eq!(
33            FixedClock("2026-01-02T03-04-05Z".into()).timestamp(),
34            "2026-01-02T03-04-05Z"
35        );
36    }
37    #[test]
38    fn system_clock_is_safe_and_zulu() {
39        let t = SystemClock.timestamp();
40        assert!(t.ends_with('Z'));
41        assert!(
42            !t.contains(':'),
43            "colons are avoided for key/filename safety"
44        );
45    }
46}
git_ark/clock.rs

git_ark/
clock.rs
