pub(crate) mod prepare_and_commit {    use std::convert::TryInto;     use git_actor::{Sign, Time};    use git_hash::ObjectId;    use git_object::bstr::BString;    use git_ref::{        file,        transaction::{Change, LogChange, PreviousValue, RefEdit, RefLog},        Target,    };     use crate::util::hex_to_id;     fn reflog_lines(store: &file::Store, name: &str) -> crate::Result<Vec<git_ref::log::Line>> {        let mut buf = Vec::new();        let res = store            .reflog_iter(name, &mut buf)?            .expect("existing reflog")            .map(|l| l.map(git_ref::log::Line::from))            .collect::<std::result::Result<Vec<_>, _>>()?;        Ok(res)    }     pub(crate) fn empty_store() -> crate::Result<(tempfile::TempDir, file::Store)> {        let dir = tempfile::TempDir::new().unwrap();        let store = file::Store::at(dir.path(), git_ref::store::WriteReflog::Normal, git_hash::Kind::Sha1);        Ok((dir, store))    }     pub(crate) fn committer() -> git_actor::Signature {        git_actor::Signature {            name: "committer".into(),            email: "committer@example.com".into(),            time: Time {                seconds_since_unix_epoch: 1234,                offset_in_seconds: 1800,                sign: Sign::Plus,            },        }    }     fn log_line(previous: ObjectId, new: ObjectId, message: impl Into<BString>) -> git_ref::log::Line {        git_ref::log::Line {            previous_oid: previous,            new_oid: new,            signature: committer(),            message: message.into(),        }    }     fn create_at(name: &str) -> RefEdit {        RefEdit {            change: Change::Update {                log: LogChange {                    mode: RefLog::AndReference,                    force_create_reflog: true,                    message: "log peeled".into(),                },                expected: PreviousValue::MustNotExist,                new: Target::Peeled(hex_to_id("e69de29bb2d1d6434b8b29ae775ad8c2e48c5391")),            },            name: name.try_into().expect("valid"),            deref: false,        }    }     fn create_symbolic_at(name: &str, symbolic_target: &str) -> RefEdit {        RefEdit {            change: Change::Update {                log: LogChange::default(),                expected: PreviousValue::MustNotExist,                new: Target::Symbolic(symbolic_target.try_into().expect("valid target name")),            },            name: name.try_into().expect("valid"),            deref: false,        }    }     fn delete_at(name: &str) -> RefEdit {        RefEdit {            change: Change::Delete {                expected: PreviousValue::Any,                log: RefLog::AndReference,            },            name: name.try_into().expect("valid name"),            deref: false,        }    }     mod create_or_update;     mod delete;}