use crate::{compound, data, loose, pack}; /// Returned by [`compound::Db::find()`]#[derive(thiserror::Error, Debug)]#[allow(missing_docs)]pub enum Error {    #[error("An error occurred while obtaining an object from the loose object store")]    Loose(#[from] loose::db::find::Error),    #[error("An error occurred while obtaining an object from the packed object store")]    Pack(#[from] pack::data::decode_entry::Error),} pub(crate) struct PackLocation {    pub pack_id: usize,    pub entry_index: u32,} impl compound::Db {    /// Find an object as identified by [`ObjectId`][git_hash::ObjectId] and store its data in full in the provided `buffer`.    /// This will search the object in all contained object databases.    /// Use a `pack_cache` to accelerate pack access by reducing the amount of work duplication, or [`pack::cache::Never`] to disable any caching.    pub fn find<'a>(        &self,        id: impl AsRef<git_hash::oid>,        buffer: &'a mut Vec<u8>,        pack_cache: &mut impl pack::cache::DecodeEntry,    ) -> Result<Option<data::Object<'a>>, Error> {        let id = id.as_ref();        for pack in &self.packs {            if let Some(idx) = pack.internal_find_pack_index(id) {                let object = pack.internal_get_object_by_index(idx, buffer, pack_cache)?;                return Ok(Some(object));            }        }        if self.loose.contains(id) {            return self.loose.find(id, buffer).map_err(Into::into);        }        Ok(None)    }     /// Internal-use function to look up a packed object index or loose object.    /// Used to avoid double-lookups in linked::Db::locate.    /// (The polonius borrow-checker would support this via the locate    /// function, so this can be [simplified](https://github.com/Byron/gitoxide/blob/0c5f4043da4615820cb180804a81c2d4fe75fe5e/git-odb/src/compound/locate.rs#L47)    /// once polonius is stable.)    pub(crate) fn internal_find(&self, id: impl AsRef<git_hash::oid>) -> Option<PackLocation> {        let id = id.as_ref();        for (pack_idx, pack) in self.packs.iter().enumerate() {            if let Some(idx) = pack.internal_find_pack_index(id) {                return Some(PackLocation {                    pack_id: pack_idx,                    entry_index: idx,                });            }        }        None    }     pub(crate) fn internal_get_packed_object_by_index<'a>(        &self,        pack_index: usize,        object_index: u32,        buffer: &'a mut Vec<u8>,        pack_cache: &mut impl pack::cache::DecodeEntry,    ) -> Result<data::Object<'a>, pack::data::decode_entry::Error> {        self.packs[pack_index].internal_get_object_by_index(object_index, buffer, pack_cache)    }}