use crate::{borrowed::parse::SPACE, borrowed::Error};use crate::{BStr, ByteSlice};use nom::{    bytes::complete::{tag, take, take_while1, take_while_m_n},    character::is_digit,    combinator::all_consuming,    multi::many1,    sequence::terminated,    IResult,};use std::convert::TryFrom; #[derive(PartialEq, Eq, Debug, Hash, Ord, PartialOrd, Clone)]#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]pub struct Tree<'a> {    #[cfg_attr(feature = "serde1", serde(borrow))]    pub entries: Vec<Entry<'a>>,} #[derive(PartialEq, Eq, Debug, Hash, Ord, PartialOrd, Clone)]#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]pub struct Entry<'a> {    pub mode: Mode,    pub filename: &'a BStr,    /// a 20 bytes SHA1    pub oid: &'a [u8],} #[derive(Clone, Copy, PartialEq, Eq, Debug, Ord, PartialOrd, Hash)]#[repr(u16)]#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]pub enum Mode {    Tree = 0o040000u16,    Blob = 0o100644,    BlobExecutable = 0o100755,    Link = 0o120000,    Commit = 0o160000,} impl TryFrom<&[u8]> for Mode {    type Error = Error;     fn try_from(mode: &[u8]) -> Result<Self, Self::Error> {        Ok(match mode {            b"40000" => Mode::Tree,            b"100644" => Mode::Blob,            b"100755" => Mode::BlobExecutable,            b"120000" => Mode::Link,            b"160000" => Mode::Commit,            _ => return Err(Error::NomDetail(mode.into(), "unknown tree mode")),        })    }} const NULL: &[u8] = b"\0";fn parse_entry(i: &[u8]) -> IResult<&[u8], Entry, Error> {    let (i, mode) = terminated(take_while_m_n(5, 6, is_digit), tag(SPACE))(i)?;    let mode = Mode::try_from(mode).map_err(nom::Err::Error)?;    let (i, filename) = terminated(take_while1(|b| b != NULL[0]), tag(NULL))(i)?;    let (i, oid) = take(20u8)(i)?;     Ok((        i,        Entry {            mode,            filename: filename.as_bstr(),            oid,        },    ))} fn parse(i: &[u8]) -> IResult<&[u8], Tree, Error> {    let (i, mut entries) = all_consuming(many1(parse_entry))(i)?;    entries.shrink_to_fit();    Ok((i, Tree { entries }))} impl<'a> Tree<'a> {    pub fn from_bytes(d: &'a [u8]) -> Result<Tree<'a>, Error> {        parse(d).map(|(_, t)| t).map_err(Error::from)    }}