use std::cmp::Ordering; use bstr::{BStr, ByteSlice, ByteVec}; use crate::{entry, extension, Entry, PathStorage, State, Version}; // TODO: integrate this somehow, somewhere, depending on later usage.#[allow(dead_code)]mod sparse; /// General information and entriesimpl State {    /// Return the version used to store this state's information on disk.    pub fn version(&self) -> Version {        self.version    }     /// Return the kind of hashes used in this instance.    pub fn object_hash(&self) -> git_hash::Kind {        self.object_hash    }     /// Return our entries    pub fn entries(&self) -> &[Entry] {        &self.entries    }    /// Return our path backing, the place which keeps all paths one after another, with entries storing only the range to access them.    pub fn path_backing(&self) -> &PathStorage {        &self.path_backing    }     /// Runs `filter_map` on all entries, returning an iterator over all paths along with the result of `filter_map`.    pub fn entries_with_paths_by_filter_map<'a, T>(        &'a self,        mut filter_map: impl FnMut(&'a BStr, &Entry) -> Option<T> + 'a,    ) -> impl Iterator<Item = (&'a BStr, T)> + 'a {        self.entries.iter().filter_map(move |e| {            let p = e.path(self);            filter_map(p, e).map(|t| (p, t))        })    }    /// Return mutable entries along with their path, as obtained from `backing`.    pub fn entries_mut_with_paths_in<'state, 'backing>(        &'state mut self,        backing: &'backing PathStorage,    ) -> impl Iterator<Item = (&'state mut Entry, &'backing BStr)> {        self.entries.iter_mut().map(move |e| {            let path = backing[e.path.clone()].as_bstr();            (e, path)        })    }     /// Find the entry index in [`entries()`][State::entries()] matching the given repository-relative    /// `path` and `stage`, or `None`.    ///    /// Use the index for accessing multiple stages if they exists, but at least the single matching entry.    pub fn entry_index_by_path_and_stage(&self, path: &BStr, stage: entry::Stage) -> Option<usize> {        self.entries            .binary_search_by(|e| e.path(self).cmp(path).then_with(|| e.stage().cmp(&stage)))            .ok()    }     /// Find the entry index in [`entries()[..upper_bound]`][State::entries()] matching the given repository-relative    /// `path` and `stage`, or `None`.    ///    /// Use the index for accessing multiple stages if they exists, but at least the single matching entry.    ///    /// # Panics    ///    /// If `upper_bound` is out of bounds of our entries array.    pub fn entry_index_by_path_and_stage_bounded(        &self,        path: &BStr,        stage: entry::Stage,        upper_bound: usize,    ) -> Option<usize> {        self.entries[..upper_bound]            .binary_search_by(|e| e.path(self).cmp(path).then_with(|| e.stage().cmp(&stage)))            .ok()    }     /// Like [`entry_index_by_path_and_stage()`][State::entry_index_by_path_and_stage()],    /// but returns the entry instead of the index.    pub fn entry_by_path_and_stage(&self, path: &BStr, stage: entry::Stage) -> Option<&Entry> {        self.entry_index_by_path_and_stage(path, stage)            .map(|idx| &self.entries[idx])    }     /// Return the entry at `idx` or _panic_ if the index is out of bounds.    ///    /// The `idx` is typically returned by [entry_by_path_and_stage()][State::entry_by_path_and_stage()].    pub fn entry(&self, idx: usize) -> &Entry {        &self.entries[idx]    }     /// Returns a boolean value indicating whether the index is sparse or not.    ///    /// An index is sparse if it contains at least one [Mode::DIR][entry::Mode::DIR] entry.    pub fn is_sparse(&self) -> bool {        self.is_sparse    }} /// Mutationimpl State {    /// After usage of the storage obtained by [`take_path_backing()`][Self::take_path_backing()], return it here.    /// Note that it must not be empty.    pub fn return_path_backing(&mut self, backing: PathStorage) {        debug_assert!(            self.path_backing.is_empty(),            "BUG: return path backing only after taking it, once"        );        self.path_backing = backing;    }     /// Return mutable entries in a slice.    pub fn entries_mut(&mut self) -> &mut [Entry] {        &mut self.entries    }    /// Return mutable entries along with their paths in an iterator.    pub fn entries_mut_with_paths(&mut self) -> impl Iterator<Item = (&mut Entry, &BStr)> {        let paths = &self.path_backing;        self.entries.iter_mut().map(move |e| {            let path = paths[e.path.clone()].as_bstr();            (e, path)        })    }     /// Sometimes it's needed to remove the path backing to allow certain mutation to happen in the state while supporting reading the entry's    /// path.    pub fn take_path_backing(&mut self) -> PathStorage {        assert_eq!(            self.entries.is_empty(),            self.path_backing.is_empty(),            "BUG: cannot take out backing multiple times"        );        std::mem::take(&mut self.path_backing)    }     /// Like [`entry_index_by_path_and_stage()`][State::entry_index_by_path_and_stage()],    /// but returns the mutable entry instead of the index.    pub fn entry_mut_by_path_and_stage(&mut self, path: &BStr, stage: entry::Stage) -> Option<&mut Entry> {        self.entry_index_by_path_and_stage(path, stage)            .map(|idx| &mut self.entries[idx])    }     /// Push a new entry containing `stat`, `id`, `flags` and `mode` and `path` to the end of our storage, without performing    /// any sanity checks. This means it's possible to push a new entry to the same path on the same stage and even after sorting    /// the entries lookups may still return the wrong one of them unless the correct binary search criteria is chosen.    ///    /// Note that this *is likely* to break invariants that will prevent further lookups by path unless    /// [`entry_index_by_path_and_stage_bounded()`][State::entry_index_by_path_and_stage_bounded()] is used with    /// the `upper_bound` being the amount of entries before the first call to this method.    ///    /// Alternatively, make sure to call [sort_entries()][State::sort_entries()] before entry lookup by path to restore    /// the invariant.    pub fn dangerously_push_entry(        &mut self,        stat: entry::Stat,        id: git_hash::ObjectId,        flags: entry::Flags,        mode: entry::Mode,        path: &BStr,    ) {        let path = {            let path_start = self.path_backing.len();            self.path_backing.push_str(path);            path_start..self.path_backing.len()        };         self.entries.push(Entry {            stat,            id,            flags,            mode,            path,        });    }     /// Unconditionally sort entries as needed to perform lookups quickly.    pub fn sort_entries(&mut self) {        let path_backing = &self.path_backing;        self.entries.sort_by(|a, b| {            Entry::cmp_filepaths(a.path_in(path_backing), b.path_in(path_backing))                .then_with(|| a.stage().cmp(&b.stage()))        });    }     /// Similar to [`sort_entries()][State::sort_entries()], but applies `compare` after comparing    /// by path and stage as a third criteria.    pub fn sort_entries_by(&mut self, mut compare: impl FnMut(&Entry, &Entry) -> Ordering) {        let path_backing = &self.path_backing;        self.entries.sort_by(|a, b| {            Entry::cmp_filepaths(a.path_in(path_backing), b.path_in(path_backing))                .then_with(|| a.stage().cmp(&b.stage()))                .then_with(|| compare(a, b))        });    }} /// Extensionsimpl State {    /// Access the `tree` extension.    pub fn tree(&self) -> Option<&extension::Tree> {        self.tree.as_ref()    }    /// Access the `link` extension.    pub fn link(&self) -> Option<&extension::Link> {        self.link.as_ref()    }    /// Obtain the resolve-undo extension.    pub fn resolve_undo(&self) -> Option<&extension::resolve_undo::Paths> {        self.resolve_undo.as_ref()    }    /// Obtain the untracked extension.    pub fn untracked(&self) -> Option<&extension::UntrackedCache> {        self.untracked.as_ref()    }    /// Obtain the fsmonitor extension.    pub fn fs_monitor(&self) -> Option<&extension::FsMonitor> {        self.fs_monitor.as_ref()    }}