use std::str::FromStr; use crate::{Error, Time};use smallvec::SmallVec; /// A container for just enough bytes to hold the largest-possible [`time`](Time) instance./// It's used in conjunction with#[derive(Default, Clone)]pub struct TimeBuf {    buf: SmallVec<[u8; Time::MAX.size()]>,} impl TimeBuf {    /// Represent this instance as standard string, serialized in a format compatible with    /// signature fields in Git commits, also known as anything parseable as [raw format](function::parse_header()).    pub fn as_str(&self) -> &str {        // Time serializes as ASCII, which is a subset of UTF-8.        let time_bytes = self.buf.as_slice();        std::str::from_utf8(time_bytes).expect("time serializes as valid UTF-8")    }     /// Clear the previous content.    fn clear(&mut self) {        self.buf.clear();    }} impl Time {    /// Serialize this instance into `buf`, exactly as it would appear in the header of a Git commit,    /// and return `buf` as `&str` for easy consumption.    pub fn to_str<'a>(&self, buf: &'a mut TimeBuf) -> &'a str {        buf.clear();        self.write_to(&mut buf.buf)            .expect("write to memory of just the right size cannot fail");        buf.as_str()    }} impl FromStr for Time {    type Err = Error;     fn from_str(s: &str) -> Result<Self, Self::Err> {        crate::parse_header(s).ok_or_else(|| Error::new_with_input("invalid time", s))    }} pub(crate) mod function;mod git;mod raw;mod relative;