use std::borrow::Cow; use crate::{    bstr::{BStr, BString, ByteSlice, ByteVec},    commit::MessageRef,    CommitRef,}; ///pub mod body;mod decode; impl<'a> CommitRef<'a> {    /// Return exactly the same message as [`MessageRef::summary()`].    pub fn message_summary(&self) -> Cow<'a, BStr> {        summary(self.message)    }     /// Return an iterator over message trailers as obtained from the last paragraph of the commit message.    /// May be empty.    pub fn message_trailers(&self) -> body::Trailers<'a> {        BodyRef::from_bytes(self.message).trailers()    }} impl<'a> MessageRef<'a> {    /// Parse the given `input` as message.    ///    /// Note that this cannot fail as everything will be interpreted as title if there is no body separator.    pub fn from_bytes(input: &'a [u8]) -> Self {        let (title, body) = decode::message(input);        MessageRef { title, body }    }     /// Produce a short commit summary for the message title.    ///    /// This means the following    ///    /// * Take the subject line which is delimited by two newlines (\n\n)    /// * transform intermediate consecutive whitespace including \r into one space    ///    /// The resulting summary will have folded whitespace before a newline into spaces and stopped that process    /// once two consecutive newlines are encountered.    pub fn summary(&self) -> Cow<'a, BStr> {        summary(self.title)    }     /// Further parse the body into into non-trailer and trailers, which can be iterated from the returned [`BodyRef`].    pub fn body(&self) -> Option<BodyRef<'a>> {        self.body.map(|b| BodyRef::from_bytes(b))    }} pub(crate) fn summary(message: &BStr) -> Cow<'_, BStr> {    let message = message.trim();    match message.find_byte(b'\n') {        Some(mut pos) => {            let mut out = BString::default();            let mut previous_pos = None;            loop {                if let Some(previous_pos) = previous_pos {                    if previous_pos + 1 == pos {                        let len_after_trim = out.trim_end().len();                        out.resize(len_after_trim, 0);                        break out.into();                    }                }                let message_to_newline = &message[previous_pos.map(|p| p + 1).unwrap_or(0)..pos];                 if let Some(pos_before_whitespace) = message_to_newline.rfind_not_byteset(b"\t\n\x0C\r ") {                    out.extend_from_slice(&message_to_newline[..pos_before_whitespace + 1]);                }                out.push_byte(b' ');                previous_pos = Some(pos);                match message.get(pos + 1..).and_then(|i| i.find_byte(b'\n')) {                    Some(next_nl_pos) => pos += next_nl_pos + 1,                    None => {                        if let Some(slice) = message.get((pos + 1)..) {                            out.extend_from_slice(slice);                        }                        break out.into();                    }                }            }        }        None => message.as_bstr().into(),    }} /// A reference to a message body, further parsed to only contain the non-trailer parts.////// See [git-interpret-trailers](https://git-scm.com/docs/git-interpret-trailers) for more information/// on what constitutes trailers and not that this implementation is only good for typical sign-off footer or key-value parsing.////// Note that we only parse trailers from the bottom of the body.#[derive(PartialEq, Eq, Debug, Hash, Ord, PartialOrd, Clone, Copy)]pub struct BodyRef<'a> {    body_without_trailer: &'a BStr,    start_of_trailer: &'a [u8],}