use std::borrow::BorrowMut; use gix_object::TreeRefIter;use gix_traverse::tree::breadthfirst; pub trait Sealed {} /// An extension trait for tree iteratorspub trait TreeIterExt: Sealed {    /// Traverse this tree with `state` being provided to potentially reuse allocations, and `find` being a function to lookup trees    /// and turn them into iterators.    ///    /// The `delegate` implements a way to store details about the traversal to allow paying only for what's actually used.    /// Since it is expected to store the operation result, _unit_ is returned.    fn traverse<StateMut, Find, V>(        &self,        state: StateMut,        objects: Find,        delegate: &mut V,    ) -> Result<(), breadthfirst::Error>    where        Find: gix_object::Find,        StateMut: BorrowMut<breadthfirst::State>,        V: gix_traverse::tree::Visit;} impl Sealed for TreeRefIter<'_> {} impl TreeIterExt for TreeRefIter<'_> {    fn traverse<StateMut, Find, V>(        &self,        state: StateMut,        objects: Find,        delegate: &mut V,    ) -> Result<(), breadthfirst::Error>    where        Find: gix_object::Find,        StateMut: BorrowMut<breadthfirst::State>,        V: gix_traverse::tree::Visit,    {        breadthfirst(*self, state, objects, delegate)    }} /// Extensions for [EntryRef](gix_object::tree::EntryRef).pub trait TreeEntryRefExt<'a>: 'a {    /// Attach [`repo`](crate::Repository) to the given tree entry. It can be detached later with `detach()`.    fn attach<'repo>(self, repo: &'repo crate::Repository) -> crate::object::tree::EntryRef<'repo, 'a>;} impl<'a> TreeEntryRefExt<'a> for gix_object::tree::EntryRef<'a> {    fn attach<'repo>(self, repo: &'repo crate::Repository) -> crate::object::tree::EntryRef<'repo, 'a> {        crate::object::tree::EntryRef { inner: self, repo }    }} /// Extensions for [Entry](gix_object::tree::Entry).pub trait TreeEntryExt {    /// Attach [`repo`](crate::Repository) to the given tree entry. It can be detached later with `detach()`.    fn attach(self, repo: &crate::Repository) -> crate::object::tree::Entry<'_>;} impl TreeEntryExt for gix_object::tree::Entry {    fn attach(self, repo: &crate::Repository) -> crate::object::tree::Entry<'_> {        crate::object::tree::Entry { inner: self, repo }    }} /// Extensions for [Change](gix_diff::tree_with_rewrites::Change).#[cfg(feature = "blob-diff")]pub trait TreeDiffChangeExt {    /// Attach [`old_repo`](crate::Repository) and `new_repo` to current instance. It can be detached later with `detach()`.    /// Note that both repositories are usually the same.    fn attach<'old, 'new>(        &self,        old_repo: &'old crate::Repository,        new_repo: &'new crate::Repository,    ) -> crate::object::tree::diff::Change<'_, 'old, 'new>;}