/// All possible values of `push.default`.#[derive(Default, Copy, Clone, PartialOrd, PartialEq, Ord, Eq, Hash, Debug)]pub enum Default {    /// Do not push anything unless a refspec is provided explicitly.    ///    /// This is for safety.    Nothing,    /// Push the current branch to update a remote branch with the same name.    Current,    /// Push the current branch to the branch it would fetch from and merge with,    /// i.e. what is configured in `branch.<name>.merge`, retrievable with    /// the `@{upstream}` refspec.    Upstream,    /// Push the current branch with the same name to the remote.    /// This is the same as [`Current`](Default::Current), but fails if    /// `branch.<name>.merge` is set to a branch that is named differently.    #[default]    Simple,    /// Push *all* branches to their similarly named counterpart on the remote.    Matching,}