pub fn update_working_copy(
repo: &Arc<ReadonlyRepo>,
workspace: &mut Workspace,
old_commit: Option<&Commit>,
new_commit: &Commit,
) -> Result<CheckoutStats, CommandError>pub fn update_working_copy(
repo: &Arc<ReadonlyRepo>,
workspace: &mut Workspace,
old_commit: Option<&Commit>,
new_commit: &Commit,
) -> Result<CheckoutStats, CommandError>