use crate::visit::record;use git_hash::ObjectId;use git_object::{    bstr::{BStr, BString, ByteSlice, ByteVec},    tree,};use std::collections::BTreeMap;use std::ops::Deref;use std::path::PathBuf; #[derive(Clone, Debug, PartialEq, Eq)]pub enum Change {    Addition {        entry_mode: tree::EntryMode,        oid: ObjectId,        path: PathBuf,    },    Deletion {        entry_mode: tree::EntryMode,        oid: ObjectId,        path: PathBuf,    },    Modification {        previous_entry_mode: tree::EntryMode,        previous_oid: ObjectId,         entry_mode: tree::EntryMode,        oid: ObjectId,         path: PathBuf,    },} pub type Changes = Vec<Change>; #[derive(Clone, Debug, Default)]pub struct Recorder {    path_count: usize,    path_map: BTreeMap<usize, BString>,    path: BString,    pub records: Vec<Change>,} impl Recorder {    fn pop_element(&mut self) {        if let Some(pos) = self.path.rfind_byte(b'/') {            self.path.resize(pos, 0);        } else {            self.path.clear();        }    }     fn push_element(&mut self, name: &BStr) {        if !self.path.is_empty() {            self.path.push(b'/');        }        self.path.push_str(name);    }     fn path_clone(&self) -> BString {        self.path.clone()    }     fn path_buf(&self) -> PathBuf {        self.path.deref().to_owned().into_path_buf_lossy()    }} impl record::Record for Recorder {    type PathId = usize;     fn set_current_path(&mut self, path: Self::PathId) {        self.path = self.path_map.remove(&path).expect("every parent is set only once");    }     fn push_tracked_path_component(&mut self, component: &BStr) -> Self::PathId {        self.push_element(component);        self.path_map.insert(self.path_count, self.path_clone());        let res = self.path_count;        self.path_count += 1;        res    }     fn push_path_component(&mut self, component: &BStr) {        self.push_element(component);    }     fn pop_path_component(&mut self) {        self.pop_element();    }     fn record(&mut self, change: record::Change) -> record::Action {        use record::Change::*;        self.records.push(match change {            Deletion { entry_mode, oid } => Change::Deletion {                entry_mode,                oid,                path: self.path_buf(),            },            Addition { entry_mode, oid } => Change::Addition {                entry_mode,                oid,                path: self.path_buf(),            },            Modification {                previous_entry_mode,                previous_oid,                entry_mode,                oid,            } => Change::Modification {                previous_entry_mode,                previous_oid,                entry_mode,                oid,                path: self.path_buf(),            },            _ => todo!("record other kinds of changes"),        });        record::Action::Continue    }}