use std::io; use bstr::{BString, ByteSlice}; use crate::{    encode::SPACE,    tree::{Entry, EntryRef},    Kind, Tree, TreeRef,}; /// The Error used in [`Tree::write_to()`][crate::WriteTo::write_to()].#[derive(Debug, thiserror::Error)]#[allow(missing_docs)]pub enum Error {    #[error("Newlines are invalid in file paths: {name:?}")]    NewlineInFilename { name: BString },} impl From<Error> for io::Error {    fn from(err: Error) -> Self {        io::Error::new(io::ErrorKind::Other, err)    }} /// Serializationimpl crate::WriteTo for Tree {    /// Serialize this tree to `out` in the git internal format.    fn write_to(&self, mut out: impl io::Write) -> io::Result<()> {        debug_assert_eq!(            &{                let mut entries_sorted = self.entries.clone();                entries_sorted.sort();                entries_sorted            },            &self.entries,            "entries for serialization must be sorted by filename"        );        for Entry { mode, filename, oid } in &self.entries {            out.write_all(mode.as_bytes())?;            out.write_all(SPACE)?;             if filename.find_byte(b'\n').is_some() {                return Err(Error::NewlineInFilename {                    name: (*filename).to_owned(),                }                .into());            }            out.write_all(filename)?;            out.write_all(&[b'\0'])?;             out.write_all(oid.as_bytes())?;        }        Ok(())    }     fn size(&self) -> usize {        self.entries            .iter()            .map(|Entry { mode, filename, oid }| mode.as_bytes().len() + 1 + filename.len() + 1 + oid.as_bytes().len())            .sum()    }     fn kind(&self) -> Kind {        Kind::Tree    }} /// Serializationimpl<'a> crate::WriteTo for TreeRef<'a> {    /// Serialize this tree to `out` in the git internal format.    fn write_to(&self, mut out: impl io::Write) -> io::Result<()> {        debug_assert_eq!(            &{                let mut entries_sorted = self.entries.clone();                entries_sorted.sort();                entries_sorted            },            &self.entries,            "entries for serialization must be sorted by filename"        );        for EntryRef { mode, filename, oid } in &self.entries {            out.write_all(mode.as_bytes())?;            out.write_all(SPACE)?;             if filename.find_byte(b'\n').is_some() {                return Err(Error::NewlineInFilename {                    name: (*filename).to_owned(),                }                .into());            }            out.write_all(filename)?;            out.write_all(&[b'\0'])?;             out.write_all(oid.as_bytes())?;        }        Ok(())    }     fn size(&self) -> usize {        self.entries            .iter()            .map(|EntryRef { mode, filename, oid }| {                mode.as_bytes().len() + 1 + filename.len() + 1 + oid.as_bytes().len()            })            .sum()    }     fn kind(&self) -> Kind {        Kind::Tree    }}