use gix_hash::ObjectId;use gix_object::{    bstr::{BStr, BString, ByteSlice, ByteVec},    tree,}; use crate::tree::{visit, visit::Relation, Recorder, Visit}; /// Describe how to track the location of a change.#[derive(Debug, Clone, Copy, Eq, PartialEq)]pub enum Location {    /// Track the entire path, relative to the repository.    Path,    /// Keep only the file-name as location, which may be enough for some calculations.    ///    /// This is less expensive than tracking the entire `Path`.    FileName,} /// A Change as observed by a call to [`visit(…)`](Visit::visit()), enhanced with the path affected by the change./// Its similar to [`visit::Change`] but includes the path that changed.#[derive(Clone, Debug, PartialEq, Eq)]#[allow(missing_docs)]pub enum Change {    Addition {        entry_mode: tree::EntryMode,        oid: ObjectId,        path: BString,        relation: Option<Relation>,    },    Deletion {        entry_mode: tree::EntryMode,        oid: ObjectId,        path: BString,        relation: Option<Relation>,    },    Modification {        previous_entry_mode: tree::EntryMode,        previous_oid: ObjectId,         entry_mode: tree::EntryMode,        oid: ObjectId,         path: BString,    },} impl Default for Recorder {    fn default() -> Self {        Recorder {            path_deque: Default::default(),            path: Default::default(),            location: Some(Location::Path),            records: vec![],        }    }} /// Builderimpl Recorder {    /// Obtain a copy of the currently tracked, full path of the entry.    pub fn track_location(mut self, location: Option<Location>) -> Self {        self.location = location;        self    }} /// Accessimpl Recorder {    /// Obtain a copy of the currently tracked, full path of the entry.    pub fn path_clone(&self) -> BString {        self.path.clone()    }     /// Return the currently set path.    pub fn path(&self) -> &BStr {        self.path.as_ref()    }} 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 name.is_empty() {            return;        }        if !self.path.is_empty() {            self.path.push(b'/');        }        self.path.push_str(name);    }} impl Visit for Recorder {    fn pop_front_tracked_path_and_set_current(&mut self) {        if let Some(Location::Path) = self.location {            self.path = self.path_deque.pop_front().expect("every parent is set only once");        }    }     fn push_back_tracked_path_component(&mut self, component: &BStr) {        match self.location {            None => {}            Some(Location::Path) => {                self.push_element(component);                self.path_deque.push_back(self.path.clone());            }            Some(Location::FileName) => {                self.path.clear();                self.path.extend_from_slice(component);            }        }    }     fn push_path_component(&mut self, component: &BStr) {        match self.location {            None => {}            Some(Location::Path) => {                self.push_element(component);            }            Some(Location::FileName) => {                self.path.clear();                self.path.extend_from_slice(component);            }        }    }     fn pop_path_component(&mut self) {        if let Some(Location::Path) = self.location {            self.pop_element();        }    }     fn visit(&mut self, change: visit::Change) -> visit::Action {        use visit::Change::*;        self.records.push(match change {            Deletion {                entry_mode,                oid,                relation,            } => Change::Deletion {                entry_mode,                oid,                path: self.path_clone(),                relation,            },            Addition {                entry_mode,                oid,                relation,            } => Change::Addition {                entry_mode,                oid,                path: self.path_clone(),                relation,            },            Modification {                previous_entry_mode,                previous_oid,                entry_mode,                oid,            } => Change::Modification {                previous_entry_mode,                previous_oid,                entry_mode,                oid,                path: self.path_clone(),            },        });        visit::Action::Continue    }}