worktree.rs

   1mod char_bag;
   2mod fuzzy;
   3mod ignore;
   4
   5use crate::{
   6    editor::{History, Snapshot as BufferSnapshot},
   7    sum_tree::{self, Cursor, Edit, SeekBias, SumTree},
   8};
   9use ::ignore::gitignore::Gitignore;
  10use anyhow::{anyhow, Context, Result};
  11pub use fuzzy::{match_paths, PathMatch};
  12use gpui::{scoped_pool, AppContext, Entity, ModelContext, ModelHandle, Task};
  13use lazy_static::lazy_static;
  14use parking_lot::Mutex;
  15use postage::{
  16    prelude::{Sink, Stream},
  17    watch,
  18};
  19use smol::{channel::Sender, Timer};
  20use std::{
  21    cmp,
  22    collections::{HashMap, HashSet},
  23    ffi::{CStr, OsStr},
  24    fmt, fs,
  25    future::Future,
  26    io::{self, Read, Write},
  27    ops::{AddAssign, Deref},
  28    os::unix::{ffi::OsStrExt, fs::MetadataExt},
  29    path::{Path, PathBuf},
  30    sync::{Arc, Weak},
  31    time::Duration,
  32};
  33
  34use self::{char_bag::CharBag, ignore::IgnoreStack};
  35
  36lazy_static! {
  37    static ref GITIGNORE: &'static OsStr = OsStr::new(".gitignore");
  38}
  39
  40#[derive(Clone, Debug)]
  41enum ScanState {
  42    Idle,
  43    Scanning,
  44    Err(Arc<io::Error>),
  45}
  46
  47pub struct Worktree {
  48    snapshot: Snapshot,
  49    background_snapshot: Arc<Mutex<Snapshot>>,
  50    handles: Arc<Mutex<HashMap<Arc<Path>, Weak<Mutex<FileHandleState>>>>>,
  51    scan_state: (watch::Sender<ScanState>, watch::Receiver<ScanState>),
  52    _event_stream_handle: fsevent::Handle,
  53    poll_scheduled: bool,
  54}
  55
  56#[derive(Clone)]
  57pub struct FileHandle {
  58    worktree: ModelHandle<Worktree>,
  59    state: Arc<Mutex<FileHandleState>>,
  60}
  61
  62struct FileHandleState {
  63    path: Arc<Path>,
  64    is_deleted: bool,
  65}
  66
  67impl Worktree {
  68    pub fn new(path: impl Into<Arc<Path>>, ctx: &mut ModelContext<Self>) -> Self {
  69        let abs_path = path.into();
  70        let root_name_chars = abs_path.file_name().map_or(Vec::new(), |n| {
  71            n.to_string_lossy().chars().chain(Some('/')).collect()
  72        });
  73        let (scan_state_tx, scan_state_rx) = smol::channel::unbounded();
  74        let id = ctx.model_id();
  75        let snapshot = Snapshot {
  76            id,
  77            scan_id: 0,
  78            abs_path,
  79            root_name_chars,
  80            ignores: Default::default(),
  81            entries: Default::default(),
  82        };
  83        let (event_stream, event_stream_handle) =
  84            fsevent::EventStream::new(&[snapshot.abs_path.as_ref()], Duration::from_millis(100));
  85
  86        let background_snapshot = Arc::new(Mutex::new(snapshot.clone()));
  87        let handles = Arc::new(Mutex::new(Default::default()));
  88
  89        let tree = Self {
  90            snapshot,
  91            background_snapshot: background_snapshot.clone(),
  92            handles: handles.clone(),
  93            scan_state: watch::channel_with(ScanState::Scanning),
  94            _event_stream_handle: event_stream_handle,
  95            poll_scheduled: false,
  96        };
  97
  98        std::thread::spawn(move || {
  99            let scanner = BackgroundScanner::new(background_snapshot, handles, scan_state_tx, id);
 100            scanner.run(event_stream)
 101        });
 102
 103        ctx.spawn_stream(scan_state_rx, Self::observe_scan_state, |_, _| {})
 104            .detach();
 105
 106        tree
 107    }
 108
 109    pub fn scan_complete(&self) -> impl Future<Output = ()> {
 110        let mut scan_state_rx = self.scan_state.1.clone();
 111        async move {
 112            let mut scan_state = Some(scan_state_rx.borrow().clone());
 113            while let Some(ScanState::Scanning) = scan_state {
 114                scan_state = scan_state_rx.recv().await;
 115            }
 116        }
 117    }
 118
 119    pub fn next_scan_complete(&self) -> impl Future<Output = ()> {
 120        let mut scan_state_rx = self.scan_state.1.clone();
 121        let mut did_scan = matches!(*scan_state_rx.borrow(), ScanState::Scanning);
 122        async move {
 123            loop {
 124                if let ScanState::Scanning = *scan_state_rx.borrow() {
 125                    did_scan = true;
 126                } else if did_scan {
 127                    break;
 128                }
 129                scan_state_rx.recv().await;
 130            }
 131        }
 132    }
 133
 134    fn observe_scan_state(&mut self, scan_state: ScanState, ctx: &mut ModelContext<Self>) {
 135        let _ = self.scan_state.0.blocking_send(scan_state);
 136        self.poll_entries(ctx);
 137    }
 138
 139    fn poll_entries(&mut self, ctx: &mut ModelContext<Self>) {
 140        self.snapshot = self.background_snapshot.lock().clone();
 141        ctx.notify();
 142
 143        if self.is_scanning() && !self.poll_scheduled {
 144            ctx.spawn(Timer::after(Duration::from_millis(100)), |this, _, ctx| {
 145                this.poll_scheduled = false;
 146                this.poll_entries(ctx);
 147            })
 148            .detach();
 149            self.poll_scheduled = true;
 150        }
 151    }
 152
 153    fn is_scanning(&self) -> bool {
 154        if let ScanState::Scanning = *self.scan_state.1.borrow() {
 155            true
 156        } else {
 157            false
 158        }
 159    }
 160
 161    pub fn snapshot(&self) -> Snapshot {
 162        self.snapshot.clone()
 163    }
 164
 165    pub fn contains_abs_path(&self, path: &Path) -> bool {
 166        path.starts_with(&self.snapshot.abs_path)
 167    }
 168
 169    pub fn load_history(
 170        &self,
 171        path: &Path,
 172        ctx: &AppContext,
 173    ) -> impl Future<Output = Result<History>> {
 174        let abs_path = self.snapshot.abs_path.join(path);
 175        ctx.background_executor().spawn(async move {
 176            let mut file = std::fs::File::open(&abs_path)?;
 177            let mut base_text = String::new();
 178            file.read_to_string(&mut base_text)?;
 179            Ok(History::new(Arc::from(base_text)))
 180        })
 181    }
 182
 183    pub fn save<'a>(
 184        &self,
 185        path: &Path,
 186        content: BufferSnapshot,
 187        ctx: &AppContext,
 188    ) -> Task<Result<()>> {
 189        let abs_path = self.snapshot.abs_path.join(path);
 190        ctx.background_executor().spawn(async move {
 191            let buffer_size = content.text_summary().bytes.min(10 * 1024);
 192            let file = std::fs::File::create(&abs_path)?;
 193            let mut writer = std::io::BufWriter::with_capacity(buffer_size, file);
 194            for chunk in content.fragments() {
 195                writer.write(chunk.as_bytes())?;
 196            }
 197            writer.flush()?;
 198            Ok(())
 199        })
 200    }
 201}
 202
 203impl Entity for Worktree {
 204    type Event = ();
 205}
 206
 207impl Deref for Worktree {
 208    type Target = Snapshot;
 209
 210    fn deref(&self) -> &Self::Target {
 211        &self.snapshot
 212    }
 213}
 214
 215impl fmt::Debug for Worktree {
 216    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 217        self.snapshot.fmt(f)
 218    }
 219}
 220
 221#[derive(Clone)]
 222pub struct Snapshot {
 223    id: usize,
 224    scan_id: usize,
 225    abs_path: Arc<Path>,
 226    root_name_chars: Vec<char>,
 227    ignores: HashMap<Arc<Path>, (Arc<Gitignore>, usize)>,
 228    entries: SumTree<Entry>,
 229}
 230
 231impl Snapshot {
 232    pub fn file_count(&self) -> usize {
 233        self.entries.summary().file_count
 234    }
 235
 236    pub fn visible_file_count(&self) -> usize {
 237        self.entries.summary().visible_file_count
 238    }
 239
 240    pub fn files(&self, start: usize) -> FileIter {
 241        FileIter::all(self, start)
 242    }
 243
 244    #[cfg(test)]
 245    pub fn paths(&self) -> impl Iterator<Item = &Arc<Path>> {
 246        let mut cursor = self.entries.cursor::<(), ()>();
 247        cursor.next();
 248        cursor.map(|entry| entry.path())
 249    }
 250
 251    pub fn visible_files(&self, start: usize) -> FileIter {
 252        FileIter::visible(self, start)
 253    }
 254
 255    fn child_entries<'a>(&'a self, path: &'a Path) -> ChildEntriesIter<'a> {
 256        ChildEntriesIter::new(path, self)
 257    }
 258
 259    pub fn root_entry(&self) -> &Entry {
 260        self.entry_for_path("").unwrap()
 261    }
 262
 263    pub fn root_name(&self) -> Option<&OsStr> {
 264        self.abs_path.file_name()
 265    }
 266
 267    pub fn root_name_chars(&self) -> &[char] {
 268        &self.root_name_chars
 269    }
 270
 271    fn entry_for_path(&self, path: impl AsRef<Path>) -> Option<&Entry> {
 272        let mut cursor = self.entries.cursor::<_, ()>();
 273        if cursor.seek(&PathSearch::Exact(path.as_ref()), SeekBias::Left) {
 274            cursor.item()
 275        } else {
 276            None
 277        }
 278    }
 279
 280    pub fn inode_for_path(&self, path: impl AsRef<Path>) -> Option<u64> {
 281        self.entry_for_path(path.as_ref()).map(|e| e.inode())
 282    }
 283
 284    fn insert_entry(&mut self, entry: Entry) {
 285        if !entry.is_dir() && entry.path().file_name() == Some(&GITIGNORE) {
 286            let (ignore, err) = Gitignore::new(self.abs_path.join(entry.path()));
 287            if let Some(err) = err {
 288                log::error!("error in ignore file {:?} - {:?}", entry.path(), err);
 289            }
 290
 291            let ignore_dir_path = entry.path().parent().unwrap();
 292            self.ignores
 293                .insert(ignore_dir_path.into(), (Arc::new(ignore), self.scan_id));
 294        }
 295        self.entries.insert(entry);
 296    }
 297
 298    fn populate_dir(
 299        &mut self,
 300        parent_path: Arc<Path>,
 301        entries: impl IntoIterator<Item = Entry>,
 302        ignore: Option<Arc<Gitignore>>,
 303    ) {
 304        let mut edits = Vec::new();
 305
 306        let mut parent_entry = self
 307            .entries
 308            .get(&PathKey(parent_path.clone()))
 309            .unwrap()
 310            .clone();
 311        if let Some(ignore) = ignore {
 312            self.ignores.insert(parent_path, (ignore, self.scan_id));
 313        }
 314        if matches!(parent_entry.kind, EntryKind::PendingDir) {
 315            parent_entry.kind = EntryKind::Dir;
 316        } else {
 317            unreachable!();
 318        }
 319        edits.push(Edit::Insert(parent_entry));
 320
 321        for entry in entries {
 322            edits.push(Edit::Insert(entry));
 323        }
 324        self.entries.edit(edits);
 325    }
 326
 327    fn remove_path(&mut self, path: &Path) {
 328        let new_entries = {
 329            let mut cursor = self.entries.cursor::<_, ()>();
 330            let mut new_entries = cursor.slice(&PathSearch::Exact(path), SeekBias::Left);
 331            cursor.seek_forward(&PathSearch::Successor(path), SeekBias::Left);
 332            new_entries.push_tree(cursor.suffix());
 333            new_entries
 334        };
 335        self.entries = new_entries;
 336
 337        if path.file_name() == Some(&GITIGNORE) {
 338            if let Some((_, scan_id)) = self.ignores.get_mut(path.parent().unwrap()) {
 339                *scan_id = self.scan_id;
 340            }
 341        }
 342    }
 343
 344    fn ignore_stack_for_path(&self, path: &Path, is_dir: bool) -> Arc<IgnoreStack> {
 345        let mut new_ignores = Vec::new();
 346        for ancestor in path.ancestors().skip(1) {
 347            if let Some((ignore, _)) = self.ignores.get(ancestor) {
 348                new_ignores.push((ancestor, Some(ignore.clone())));
 349            } else {
 350                new_ignores.push((ancestor, None));
 351            }
 352        }
 353
 354        let mut ignore_stack = IgnoreStack::none();
 355        for (parent_path, ignore) in new_ignores.into_iter().rev() {
 356            if ignore_stack.is_path_ignored(&parent_path, true) {
 357                ignore_stack = IgnoreStack::all();
 358                break;
 359            } else if let Some(ignore) = ignore {
 360                ignore_stack = ignore_stack.append(Arc::from(parent_path), ignore);
 361            }
 362        }
 363
 364        if ignore_stack.is_path_ignored(path, is_dir) {
 365            ignore_stack = IgnoreStack::all();
 366        }
 367
 368        ignore_stack
 369    }
 370}
 371
 372impl fmt::Debug for Snapshot {
 373    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 374        for entry in self.entries.cursor::<(), ()>() {
 375            for _ in entry.path().ancestors().skip(1) {
 376                write!(f, " ")?;
 377            }
 378            writeln!(f, "{:?} (inode: {})", entry.path(), entry.inode())?;
 379        }
 380        Ok(())
 381    }
 382}
 383
 384impl FileHandle {
 385    pub fn path(&self) -> Arc<Path> {
 386        self.state.lock().path.clone()
 387    }
 388
 389    pub fn load_history(&self, ctx: &AppContext) -> impl Future<Output = Result<History>> {
 390        self.worktree.read(ctx).load_history(&self.path(), ctx)
 391    }
 392
 393    pub fn save<'a>(&self, content: BufferSnapshot, ctx: &AppContext) -> Task<Result<()>> {
 394        let worktree = self.worktree.read(ctx);
 395        worktree.save(&self.path(), content, ctx)
 396    }
 397
 398    pub fn entry_id(&self) -> (usize, Arc<Path>) {
 399        (self.worktree.id(), self.path())
 400    }
 401}
 402
 403#[derive(Clone, Debug)]
 404pub struct Entry {
 405    kind: EntryKind,
 406    path: Arc<Path>,
 407    inode: u64,
 408    is_symlink: bool,
 409    is_ignored: bool,
 410}
 411
 412#[derive(Clone, Debug)]
 413pub enum EntryKind {
 414    PendingDir,
 415    Dir,
 416    File(CharBag),
 417}
 418
 419impl Entry {
 420    pub fn path(&self) -> &Arc<Path> {
 421        &self.path
 422    }
 423
 424    pub fn inode(&self) -> u64 {
 425        self.inode
 426    }
 427
 428    pub fn is_ignored(&self) -> bool {
 429        self.is_ignored
 430    }
 431
 432    fn is_dir(&self) -> bool {
 433        matches!(self.kind, EntryKind::Dir | EntryKind::PendingDir)
 434    }
 435}
 436
 437impl sum_tree::Item for Entry {
 438    type Summary = EntrySummary;
 439
 440    fn summary(&self) -> Self::Summary {
 441        let file_count;
 442        let visible_file_count;
 443        if matches!(self.kind, EntryKind::File(_)) {
 444            file_count = 1;
 445            if self.is_ignored {
 446                visible_file_count = 0;
 447            } else {
 448                visible_file_count = 1;
 449            }
 450        } else {
 451            file_count = 0;
 452            visible_file_count = 0;
 453        }
 454
 455        EntrySummary {
 456            max_path: self.path().clone(),
 457            file_count,
 458            visible_file_count,
 459        }
 460    }
 461}
 462
 463impl sum_tree::KeyedItem for Entry {
 464    type Key = PathKey;
 465
 466    fn key(&self) -> Self::Key {
 467        PathKey(self.path().clone())
 468    }
 469}
 470
 471#[derive(Clone, Debug)]
 472pub struct EntrySummary {
 473    max_path: Arc<Path>,
 474    file_count: usize,
 475    visible_file_count: usize,
 476}
 477
 478impl Default for EntrySummary {
 479    fn default() -> Self {
 480        Self {
 481            max_path: Arc::from(Path::new("")),
 482            file_count: 0,
 483            visible_file_count: 0,
 484        }
 485    }
 486}
 487
 488impl<'a> AddAssign<&'a EntrySummary> for EntrySummary {
 489    fn add_assign(&mut self, rhs: &'a EntrySummary) {
 490        self.max_path = rhs.max_path.clone();
 491        self.file_count += rhs.file_count;
 492        self.visible_file_count += rhs.visible_file_count;
 493    }
 494}
 495
 496#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
 497pub struct PathKey(Arc<Path>);
 498
 499impl Default for PathKey {
 500    fn default() -> Self {
 501        Self(Path::new("").into())
 502    }
 503}
 504
 505impl<'a> sum_tree::Dimension<'a, EntrySummary> for PathKey {
 506    fn add_summary(&mut self, summary: &'a EntrySummary) {
 507        self.0 = summary.max_path.clone();
 508    }
 509}
 510
 511#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 512enum PathSearch<'a> {
 513    Exact(&'a Path),
 514    Successor(&'a Path),
 515}
 516
 517impl<'a> Ord for PathSearch<'a> {
 518    fn cmp(&self, other: &Self) -> cmp::Ordering {
 519        match (self, other) {
 520            (Self::Exact(a), Self::Exact(b)) => a.cmp(b),
 521            (Self::Successor(a), Self::Exact(b)) => {
 522                if b.starts_with(a) {
 523                    cmp::Ordering::Greater
 524                } else {
 525                    a.cmp(b)
 526                }
 527            }
 528            _ => todo!("not sure we need the other two cases"),
 529        }
 530    }
 531}
 532
 533impl<'a> PartialOrd for PathSearch<'a> {
 534    fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
 535        Some(self.cmp(other))
 536    }
 537}
 538
 539impl<'a> Default for PathSearch<'a> {
 540    fn default() -> Self {
 541        Self::Exact(Path::new("").into())
 542    }
 543}
 544
 545impl<'a: 'b, 'b> sum_tree::Dimension<'a, EntrySummary> for PathSearch<'b> {
 546    fn add_summary(&mut self, summary: &'a EntrySummary) {
 547        *self = Self::Exact(summary.max_path.as_ref());
 548    }
 549}
 550
 551#[derive(Copy, Clone, Default, Debug, Eq, PartialEq, Ord, PartialOrd)]
 552pub struct FileCount(usize);
 553
 554impl<'a> sum_tree::Dimension<'a, EntrySummary> for FileCount {
 555    fn add_summary(&mut self, summary: &'a EntrySummary) {
 556        self.0 += summary.file_count;
 557    }
 558}
 559
 560#[derive(Copy, Clone, Default, Debug, Eq, PartialEq, Ord, PartialOrd)]
 561pub struct VisibleFileCount(usize);
 562
 563impl<'a> sum_tree::Dimension<'a, EntrySummary> for VisibleFileCount {
 564    fn add_summary(&mut self, summary: &'a EntrySummary) {
 565        self.0 += summary.visible_file_count;
 566    }
 567}
 568
 569struct BackgroundScanner {
 570    snapshot: Arc<Mutex<Snapshot>>,
 571    notify: Sender<ScanState>,
 572    handles: Arc<Mutex<HashMap<Arc<Path>, Weak<Mutex<FileHandleState>>>>>,
 573    other_mount_paths: HashSet<PathBuf>,
 574    thread_pool: scoped_pool::Pool,
 575    root_char_bag: CharBag,
 576}
 577
 578impl BackgroundScanner {
 579    fn new(
 580        snapshot: Arc<Mutex<Snapshot>>,
 581        handles: Arc<Mutex<HashMap<Arc<Path>, Weak<Mutex<FileHandleState>>>>>,
 582        notify: Sender<ScanState>,
 583        worktree_id: usize,
 584    ) -> Self {
 585        let root_char_bag = CharBag::from(snapshot.lock().root_name_chars.as_slice());
 586        let mut scanner = Self {
 587            root_char_bag,
 588            snapshot,
 589            notify,
 590            handles,
 591            other_mount_paths: Default::default(),
 592            thread_pool: scoped_pool::Pool::new(16, format!("worktree-{}-scanner", worktree_id)),
 593        };
 594        scanner.update_other_mount_paths();
 595        scanner
 596    }
 597
 598    fn update_other_mount_paths(&mut self) {
 599        let path = self.snapshot.lock().abs_path.clone();
 600        self.other_mount_paths.clear();
 601        self.other_mount_paths.extend(
 602            mounted_volume_paths()
 603                .into_iter()
 604                .filter(|mount_path| !path.starts_with(mount_path)),
 605        );
 606    }
 607
 608    fn abs_path(&self) -> Arc<Path> {
 609        self.snapshot.lock().abs_path.clone()
 610    }
 611
 612    fn snapshot(&self) -> Snapshot {
 613        self.snapshot.lock().clone()
 614    }
 615
 616    fn run(mut self, event_stream: fsevent::EventStream) {
 617        if smol::block_on(self.notify.send(ScanState::Scanning)).is_err() {
 618            return;
 619        }
 620
 621        if let Err(err) = self.scan_dirs() {
 622            if smol::block_on(self.notify.send(ScanState::Err(Arc::new(err)))).is_err() {
 623                return;
 624            }
 625        }
 626
 627        if smol::block_on(self.notify.send(ScanState::Idle)).is_err() {
 628            return;
 629        }
 630
 631        event_stream.run(move |events| {
 632            if smol::block_on(self.notify.send(ScanState::Scanning)).is_err() {
 633                return false;
 634            }
 635
 636            if !self.process_events(events) {
 637                return false;
 638            }
 639
 640            if smol::block_on(self.notify.send(ScanState::Idle)).is_err() {
 641                return false;
 642            }
 643
 644            true
 645        });
 646    }
 647
 648    fn scan_dirs(&self) -> io::Result<()> {
 649        self.snapshot.lock().scan_id += 1;
 650
 651        let path: Arc<Path> = Arc::from(Path::new(""));
 652        let abs_path = self.abs_path();
 653        let metadata = fs::metadata(&abs_path)?;
 654        let inode = metadata.ino();
 655        let is_symlink = fs::symlink_metadata(&abs_path)?.file_type().is_symlink();
 656
 657        if metadata.file_type().is_dir() {
 658            let dir_entry = Entry {
 659                kind: EntryKind::PendingDir,
 660                path: path.clone(),
 661                inode,
 662                is_symlink,
 663                is_ignored: false,
 664            };
 665            self.snapshot.lock().insert_entry(dir_entry);
 666
 667            let (tx, rx) = crossbeam_channel::unbounded();
 668
 669            tx.send(ScanJob {
 670                abs_path: abs_path.to_path_buf(),
 671                path,
 672                ignore_stack: IgnoreStack::none(),
 673                scan_queue: tx.clone(),
 674            })
 675            .unwrap();
 676            drop(tx);
 677
 678            self.thread_pool.scoped(|pool| {
 679                for _ in 0..self.thread_pool.thread_count() {
 680                    pool.execute(|| {
 681                        while let Ok(job) = rx.recv() {
 682                            if let Err(err) = self.scan_dir(&job) {
 683                                log::error!("error scanning {:?}: {}", job.abs_path, err);
 684                            }
 685                        }
 686                    });
 687                }
 688            });
 689        } else {
 690            self.snapshot.lock().insert_entry(Entry {
 691                kind: EntryKind::File(self.char_bag(&path)),
 692                path,
 693                inode,
 694                is_symlink,
 695                is_ignored: false,
 696            });
 697        }
 698
 699        Ok(())
 700    }
 701
 702    fn scan_dir(&self, job: &ScanJob) -> io::Result<()> {
 703        let mut new_entries: Vec<Entry> = Vec::new();
 704        let mut new_jobs: Vec<ScanJob> = Vec::new();
 705        let mut ignore_stack = job.ignore_stack.clone();
 706        let mut new_ignore = None;
 707
 708        for child_entry in fs::read_dir(&job.abs_path)? {
 709            let child_entry = child_entry?;
 710            let child_name = child_entry.file_name();
 711            let child_abs_path = job.abs_path.join(&child_name);
 712            let child_path: Arc<Path> = job.path.join(&child_name).into();
 713            let child_metadata = child_entry.metadata()?;
 714            let child_inode = child_metadata.ino();
 715            let child_is_symlink = child_metadata.file_type().is_symlink();
 716
 717            // Disallow mount points outside the file system containing the root of this worktree
 718            if self.other_mount_paths.contains(&child_abs_path) {
 719                continue;
 720            }
 721
 722            // If we find a .gitignore, add it to the stack of ignores used to determine which paths are ignored
 723            if child_name == *GITIGNORE {
 724                let (ignore, err) = Gitignore::new(&child_abs_path);
 725                if let Some(err) = err {
 726                    log::error!("error in ignore file {:?} - {:?}", child_path, err);
 727                }
 728                let ignore = Arc::new(ignore);
 729                ignore_stack = ignore_stack.append(job.path.clone(), ignore.clone());
 730                new_ignore = Some(ignore);
 731
 732                // Update ignore status of any child entries we've already processed to reflect the
 733                // ignore file in the current directory. Because `.gitignore` starts with a `.`,
 734                // there should rarely be too numerous. Update the ignore stack associated with any
 735                // new jobs as well.
 736                let mut new_jobs = new_jobs.iter_mut();
 737                for entry in &mut new_entries {
 738                    entry.is_ignored = ignore_stack.is_path_ignored(&entry.path, entry.is_dir());
 739                    if entry.is_dir() {
 740                        new_jobs.next().unwrap().ignore_stack = if entry.is_ignored {
 741                            IgnoreStack::all()
 742                        } else {
 743                            ignore_stack.clone()
 744                        };
 745                    }
 746                }
 747            }
 748
 749            if child_metadata.is_dir() {
 750                let is_ignored = ignore_stack.is_path_ignored(&child_path, true);
 751                new_entries.push(Entry {
 752                    kind: EntryKind::PendingDir,
 753                    path: child_path.clone(),
 754                    inode: child_inode,
 755                    is_symlink: child_is_symlink,
 756                    is_ignored,
 757                });
 758                new_jobs.push(ScanJob {
 759                    abs_path: child_abs_path,
 760                    path: child_path,
 761                    ignore_stack: if is_ignored {
 762                        IgnoreStack::all()
 763                    } else {
 764                        ignore_stack.clone()
 765                    },
 766                    scan_queue: job.scan_queue.clone(),
 767                });
 768            } else {
 769                let is_ignored = ignore_stack.is_path_ignored(&child_path, false);
 770                new_entries.push(Entry {
 771                    kind: EntryKind::File(self.char_bag(&child_path)),
 772                    path: child_path,
 773                    inode: child_inode,
 774                    is_symlink: child_is_symlink,
 775                    is_ignored,
 776                });
 777            };
 778        }
 779
 780        self.snapshot
 781            .lock()
 782            .populate_dir(job.path.clone(), new_entries, new_ignore);
 783        for new_job in new_jobs {
 784            job.scan_queue.send(new_job).unwrap();
 785        }
 786
 787        Ok(())
 788    }
 789
 790    fn process_events(&mut self, mut events: Vec<fsevent::Event>) -> bool {
 791        self.update_other_mount_paths();
 792
 793        let mut snapshot = self.snapshot();
 794        snapshot.scan_id += 1;
 795
 796        let root_abs_path = if let Ok(abs_path) = snapshot.abs_path.canonicalize() {
 797            abs_path
 798        } else {
 799            return false;
 800        };
 801
 802        events.sort_unstable_by(|a, b| a.path.cmp(&b.path));
 803        let mut abs_paths = events.into_iter().map(|e| e.path).peekable();
 804        let (scan_queue_tx, scan_queue_rx) = crossbeam_channel::unbounded();
 805
 806        while let Some(abs_path) = abs_paths.next() {
 807            let path = match abs_path.strip_prefix(&root_abs_path) {
 808                Ok(path) => Arc::from(path.to_path_buf()),
 809                Err(_) => {
 810                    log::error!(
 811                        "unexpected event {:?} for root path {:?}",
 812                        abs_path,
 813                        root_abs_path
 814                    );
 815                    continue;
 816                }
 817            };
 818
 819            while abs_paths.peek().map_or(false, |p| p.starts_with(&abs_path)) {
 820                abs_paths.next();
 821            }
 822
 823            snapshot.remove_path(&path);
 824
 825            match self.fs_entry_for_path(path.clone(), &abs_path) {
 826                Ok(Some(mut fs_entry)) => {
 827                    let is_dir = fs_entry.is_dir();
 828                    let ignore_stack = snapshot.ignore_stack_for_path(&path, is_dir);
 829                    fs_entry.is_ignored = ignore_stack.is_all();
 830                    snapshot.insert_entry(fs_entry);
 831                    if is_dir {
 832                        scan_queue_tx
 833                            .send(ScanJob {
 834                                abs_path,
 835                                path,
 836                                ignore_stack,
 837                                scan_queue: scan_queue_tx.clone(),
 838                            })
 839                            .unwrap();
 840                    }
 841                }
 842                Ok(None) => {}
 843                Err(err) => {
 844                    // TODO - create a special 'error' entry in the entries tree to mark this
 845                    log::error!("error reading file on event {:?}", err);
 846                }
 847            }
 848        }
 849
 850        *self.snapshot.lock() = snapshot;
 851
 852        // Scan any directories that were created as part of this event batch.
 853        drop(scan_queue_tx);
 854        self.thread_pool.scoped(|pool| {
 855            for _ in 0..self.thread_pool.thread_count() {
 856                pool.execute(|| {
 857                    while let Ok(job) = scan_queue_rx.recv() {
 858                        if let Err(err) = self.scan_dir(&job) {
 859                            log::error!("error scanning {:?}: {}", job.abs_path, err);
 860                        }
 861                    }
 862                });
 863            }
 864        });
 865
 866        self.update_ignore_statuses();
 867
 868        true
 869    }
 870
 871    fn update_ignore_statuses(&self) {
 872        let mut snapshot = self.snapshot();
 873
 874        let mut ignores_to_update = Vec::new();
 875        let mut ignores_to_delete = Vec::new();
 876        for (parent_path, (_, scan_id)) in &snapshot.ignores {
 877            if *scan_id == snapshot.scan_id && snapshot.entry_for_path(parent_path).is_some() {
 878                ignores_to_update.push(parent_path.clone());
 879            }
 880
 881            let ignore_path = parent_path.join(&*GITIGNORE);
 882            if snapshot.entry_for_path(ignore_path).is_none() {
 883                ignores_to_delete.push(parent_path.clone());
 884            }
 885        }
 886
 887        for parent_path in ignores_to_delete {
 888            snapshot.ignores.remove(&parent_path);
 889            self.snapshot.lock().ignores.remove(&parent_path);
 890        }
 891
 892        let (ignore_queue_tx, ignore_queue_rx) = crossbeam_channel::unbounded();
 893        ignores_to_update.sort_unstable();
 894        let mut ignores_to_update = ignores_to_update.into_iter().peekable();
 895        while let Some(parent_path) = ignores_to_update.next() {
 896            while ignores_to_update
 897                .peek()
 898                .map_or(false, |p| p.starts_with(&parent_path))
 899            {
 900                ignores_to_update.next().unwrap();
 901            }
 902
 903            let ignore_stack = snapshot.ignore_stack_for_path(&parent_path, true);
 904            ignore_queue_tx
 905                .send(UpdateIgnoreStatusJob {
 906                    path: parent_path,
 907                    ignore_stack,
 908                    ignore_queue: ignore_queue_tx.clone(),
 909                })
 910                .unwrap();
 911        }
 912        drop(ignore_queue_tx);
 913
 914        self.thread_pool.scoped(|scope| {
 915            for _ in 0..self.thread_pool.thread_count() {
 916                scope.execute(|| {
 917                    while let Ok(job) = ignore_queue_rx.recv() {
 918                        self.update_ignore_status(job, &snapshot);
 919                    }
 920                });
 921            }
 922        });
 923    }
 924
 925    fn update_ignore_status(&self, job: UpdateIgnoreStatusJob, snapshot: &Snapshot) {
 926        let mut ignore_stack = job.ignore_stack;
 927        if let Some((ignore, _)) = snapshot.ignores.get(&job.path) {
 928            ignore_stack = ignore_stack.append(job.path.clone(), ignore.clone());
 929        }
 930
 931        let mut edits = Vec::new();
 932        for mut entry in snapshot.child_entries(&job.path).cloned() {
 933            let was_ignored = entry.is_ignored;
 934            entry.is_ignored = ignore_stack.is_path_ignored(entry.path(), entry.is_dir());
 935            if entry.is_dir() {
 936                let child_ignore_stack = if entry.is_ignored {
 937                    IgnoreStack::all()
 938                } else {
 939                    ignore_stack.clone()
 940                };
 941                job.ignore_queue
 942                    .send(UpdateIgnoreStatusJob {
 943                        path: entry.path().clone(),
 944                        ignore_stack: child_ignore_stack,
 945                        ignore_queue: job.ignore_queue.clone(),
 946                    })
 947                    .unwrap();
 948            }
 949
 950            if entry.is_ignored != was_ignored {
 951                edits.push(Edit::Insert(entry));
 952            }
 953        }
 954        self.snapshot.lock().entries.edit(edits);
 955    }
 956
 957    fn fs_entry_for_path(&self, path: Arc<Path>, abs_path: &Path) -> Result<Option<Entry>> {
 958        let metadata = match fs::metadata(&abs_path) {
 959            Err(err) => {
 960                return match (err.kind(), err.raw_os_error()) {
 961                    (io::ErrorKind::NotFound, _) => Ok(None),
 962                    (io::ErrorKind::Other, Some(libc::ENOTDIR)) => Ok(None),
 963                    _ => Err(anyhow::Error::new(err)),
 964                }
 965            }
 966            Ok(metadata) => metadata,
 967        };
 968        let inode = metadata.ino();
 969        let is_symlink = fs::symlink_metadata(&abs_path)
 970            .context("failed to read symlink metadata")?
 971            .file_type()
 972            .is_symlink();
 973
 974        let entry = Entry {
 975            kind: if metadata.file_type().is_dir() {
 976                EntryKind::PendingDir
 977            } else {
 978                EntryKind::File(self.char_bag(&path))
 979            },
 980            path,
 981            inode,
 982            is_symlink,
 983            is_ignored: false,
 984        };
 985
 986        Ok(Some(entry))
 987    }
 988
 989    fn char_bag(&self, path: &Path) -> CharBag {
 990        let mut result = self.root_char_bag;
 991        result.extend(path.to_string_lossy().chars());
 992        result
 993    }
 994}
 995
 996struct ScanJob {
 997    abs_path: PathBuf,
 998    path: Arc<Path>,
 999    ignore_stack: Arc<IgnoreStack>,
1000    scan_queue: crossbeam_channel::Sender<ScanJob>,
1001}
1002
1003struct UpdateIgnoreStatusJob {
1004    path: Arc<Path>,
1005    ignore_stack: Arc<IgnoreStack>,
1006    ignore_queue: crossbeam_channel::Sender<UpdateIgnoreStatusJob>,
1007}
1008
1009pub trait WorktreeHandle {
1010    fn file(&self, path: impl AsRef<Path>, app: &AppContext) -> Result<FileHandle>;
1011}
1012
1013impl WorktreeHandle for ModelHandle<Worktree> {
1014    fn file(&self, path: impl AsRef<Path>, app: &AppContext) -> Result<FileHandle> {
1015        let tree = self.read(app);
1016        let entry = tree
1017            .entry_for_path(&path)
1018            .ok_or_else(|| anyhow!("path does not exist in tree"))?;
1019        let path = entry.path().clone();
1020        let mut handles = tree.handles.lock();
1021        let state = if let Some(state) = handles.get(&path).and_then(Weak::upgrade) {
1022            state
1023        } else {
1024            let state = Arc::new(Mutex::new(FileHandleState {
1025                path: path.clone(),
1026                is_deleted: false,
1027            }));
1028            handles.insert(path, Arc::downgrade(&state));
1029            state
1030        };
1031
1032        Ok(FileHandle {
1033            worktree: self.clone(),
1034            state,
1035        })
1036    }
1037}
1038
1039pub enum FileIter<'a> {
1040    All(Cursor<'a, Entry, FileCount, FileCount>),
1041    Visible(Cursor<'a, Entry, VisibleFileCount, VisibleFileCount>),
1042}
1043
1044impl<'a> FileIter<'a> {
1045    fn all(snapshot: &'a Snapshot, start: usize) -> Self {
1046        let mut cursor = snapshot.entries.cursor();
1047        cursor.seek(&FileCount(start), SeekBias::Right);
1048        Self::All(cursor)
1049    }
1050
1051    fn visible(snapshot: &'a Snapshot, start: usize) -> Self {
1052        let mut cursor = snapshot.entries.cursor();
1053        cursor.seek(&VisibleFileCount(start), SeekBias::Right);
1054        Self::Visible(cursor)
1055    }
1056
1057    fn next_internal(&mut self) {
1058        match self {
1059            Self::All(cursor) => {
1060                let ix = *cursor.start();
1061                cursor.seek_forward(&FileCount(ix.0 + 1), SeekBias::Right);
1062            }
1063            Self::Visible(cursor) => {
1064                let ix = *cursor.start();
1065                cursor.seek_forward(&VisibleFileCount(ix.0 + 1), SeekBias::Right);
1066            }
1067        }
1068    }
1069
1070    fn item(&self) -> Option<&'a Entry> {
1071        match self {
1072            Self::All(cursor) => cursor.item(),
1073            Self::Visible(cursor) => cursor.item(),
1074        }
1075    }
1076}
1077
1078impl<'a> Iterator for FileIter<'a> {
1079    type Item = &'a Entry;
1080
1081    fn next(&mut self) -> Option<Self::Item> {
1082        if let Some(entry) = self.item() {
1083            self.next_internal();
1084            Some(entry)
1085        } else {
1086            None
1087        }
1088    }
1089}
1090
1091struct ChildEntriesIter<'a> {
1092    parent_path: &'a Path,
1093    cursor: Cursor<'a, Entry, PathSearch<'a>, ()>,
1094}
1095
1096impl<'a> ChildEntriesIter<'a> {
1097    fn new(parent_path: &'a Path, snapshot: &'a Snapshot) -> Self {
1098        let mut cursor = snapshot.entries.cursor();
1099        cursor.seek(&PathSearch::Exact(parent_path), SeekBias::Right);
1100        Self {
1101            parent_path,
1102            cursor,
1103        }
1104    }
1105}
1106
1107impl<'a> Iterator for ChildEntriesIter<'a> {
1108    type Item = &'a Entry;
1109
1110    fn next(&mut self) -> Option<Self::Item> {
1111        if let Some(item) = self.cursor.item() {
1112            if item.path().starts_with(self.parent_path) {
1113                self.cursor
1114                    .seek_forward(&PathSearch::Successor(item.path()), SeekBias::Left);
1115                Some(item)
1116            } else {
1117                None
1118            }
1119        } else {
1120            None
1121        }
1122    }
1123}
1124
1125fn mounted_volume_paths() -> Vec<PathBuf> {
1126    unsafe {
1127        let mut stat_ptr: *mut libc::statfs = std::ptr::null_mut();
1128        let count = libc::getmntinfo(&mut stat_ptr as *mut _, libc::MNT_WAIT);
1129        if count >= 0 {
1130            std::slice::from_raw_parts(stat_ptr, count as usize)
1131                .iter()
1132                .map(|stat| {
1133                    PathBuf::from(OsStr::from_bytes(
1134                        CStr::from_ptr(&stat.f_mntonname[0]).to_bytes(),
1135                    ))
1136                })
1137                .collect()
1138        } else {
1139            panic!("failed to run getmntinfo");
1140        }
1141    }
1142}
1143
1144#[cfg(test)]
1145mod tests {
1146    use super::*;
1147    use crate::editor::Buffer;
1148    use crate::test::*;
1149    use anyhow::Result;
1150    use gpui::App;
1151    use rand::prelude::*;
1152    use serde_json::json;
1153    use std::env;
1154    use std::fmt::Write;
1155    use std::os::unix;
1156    use std::time::{SystemTime, UNIX_EPOCH};
1157
1158    #[test]
1159    fn test_populate_and_search() {
1160        App::test_async((), |mut app| async move {
1161            let dir = temp_tree(json!({
1162                "root": {
1163                    "apple": "",
1164                    "banana": {
1165                        "carrot": {
1166                            "date": "",
1167                            "endive": "",
1168                        }
1169                    },
1170                    "fennel": {
1171                        "grape": "",
1172                    }
1173                }
1174            }));
1175
1176            let root_link_path = dir.path().join("root_link");
1177            unix::fs::symlink(&dir.path().join("root"), &root_link_path).unwrap();
1178
1179            let tree = app.add_model(|ctx| Worktree::new(root_link_path, ctx));
1180
1181            app.read(|ctx| tree.read(ctx).scan_complete()).await;
1182            app.read(|ctx| {
1183                let tree = tree.read(ctx);
1184                assert_eq!(tree.file_count(), 4);
1185                let results = match_paths(
1186                    Some(tree.snapshot()).iter(),
1187                    "bna",
1188                    false,
1189                    false,
1190                    false,
1191                    10,
1192                    ctx.thread_pool().clone(),
1193                )
1194                .into_iter()
1195                .map(|result| result.path)
1196                .collect::<Vec<Arc<Path>>>();
1197                assert_eq!(
1198                    results,
1199                    vec![
1200                        PathBuf::from("banana/carrot/date").into(),
1201                        PathBuf::from("banana/carrot/endive").into(),
1202                    ]
1203                );
1204            })
1205        });
1206    }
1207
1208    #[test]
1209    fn test_save_file() {
1210        App::test_async((), |mut app| async move {
1211            let dir = temp_tree(json!({
1212                "file1": "the old contents",
1213            }));
1214
1215            let tree = app.add_model(|ctx| Worktree::new(dir.path(), ctx));
1216            app.read(|ctx| tree.read(ctx).scan_complete()).await;
1217            app.read(|ctx| assert_eq!(tree.read(ctx).file_count(), 1));
1218
1219            let buffer = Buffer::new(1, "a line of text.\n".repeat(10 * 1024));
1220
1221            let path = tree.update(&mut app, |tree, ctx| {
1222                let path = tree.files(0).next().unwrap().path().clone();
1223                assert_eq!(path.file_name().unwrap(), "file1");
1224                smol::block_on(tree.save(&path, buffer.snapshot(), ctx.as_ref())).unwrap();
1225                path
1226            });
1227
1228            let loaded_history = app
1229                .read(|ctx| tree.read(ctx).load_history(&path, ctx))
1230                .await
1231                .unwrap();
1232            assert_eq!(loaded_history.base_text.as_ref(), buffer.text());
1233        });
1234    }
1235
1236    #[test]
1237    fn test_rescan_simple() {
1238        App::test_async((), |mut app| async move {
1239            let dir = temp_tree(json!({
1240                "a": {
1241                    "file1": "",
1242                },
1243                "b": {
1244                    "c": {
1245                        "file2": "",
1246                    }
1247                }
1248            }));
1249
1250            let tree = app.add_model(|ctx| Worktree::new(dir.path(), ctx));
1251            app.read(|ctx| tree.read(ctx).scan_complete()).await;
1252            app.read(|ctx| assert_eq!(tree.read(ctx).file_count(), 2));
1253
1254            let file2 = app.read(|ctx| {
1255                let file2 = tree.file("b/c/file2", ctx).unwrap();
1256                assert_eq!(file2.path().as_ref(), Path::new("b/c/file2"));
1257                file2
1258            });
1259
1260            std::fs::rename(dir.path().join("b/c"), dir.path().join("d")).unwrap();
1261
1262            app.read(|ctx| tree.read(ctx).next_scan_complete()).await;
1263
1264            app.read(|ctx| {
1265                assert_eq!(
1266                    tree.read(ctx)
1267                        .paths()
1268                        .map(|p| p.to_str().unwrap())
1269                        .collect::<Vec<_>>(),
1270                    vec!["a", "a/file1", "b", "d", "d/file2"]
1271                )
1272            });
1273
1274            // tree.condition(&app, move |_, _| {
1275            //     file2.path().as_ref() == Path::new("d/file2")
1276            // })
1277            // .await;
1278        });
1279    }
1280
1281    #[test]
1282    fn test_rescan_with_gitignore() {
1283        App::test_async((), |mut app| async move {
1284            let dir = temp_tree(json!({
1285                ".git": {},
1286                ".gitignore": "ignored-dir\n",
1287                "tracked-dir": {
1288                    "tracked-file1": "tracked contents",
1289                },
1290                "ignored-dir": {
1291                    "ignored-file1": "ignored contents",
1292                }
1293            }));
1294
1295            let tree = app.add_model(|ctx| Worktree::new(dir.path(), ctx));
1296            app.read(|ctx| tree.read(ctx).scan_complete()).await;
1297            app.read(|ctx| {
1298                let tree = tree.read(ctx);
1299                let tracked = tree.entry_for_path("tracked-dir/tracked-file1").unwrap();
1300                let ignored = tree.entry_for_path("ignored-dir/ignored-file1").unwrap();
1301                assert_eq!(tracked.is_ignored(), false);
1302                assert_eq!(ignored.is_ignored(), true);
1303            });
1304
1305            fs::write(dir.path().join("tracked-dir/tracked-file2"), "").unwrap();
1306            fs::write(dir.path().join("ignored-dir/ignored-file2"), "").unwrap();
1307            app.read(|ctx| tree.read(ctx).next_scan_complete()).await;
1308            app.read(|ctx| {
1309                let tree = tree.read(ctx);
1310                let tracked = tree.entry_for_path("tracked-dir/tracked-file2").unwrap();
1311                let ignored = tree.entry_for_path("ignored-dir/ignored-file2").unwrap();
1312                assert_eq!(tracked.is_ignored(), false);
1313                assert_eq!(ignored.is_ignored(), true);
1314            });
1315        });
1316    }
1317
1318    #[test]
1319    fn test_mounted_volume_paths() {
1320        let paths = mounted_volume_paths();
1321        assert!(paths.contains(&"/".into()));
1322    }
1323
1324    #[test]
1325    fn test_random() {
1326        let iterations = env::var("ITERATIONS")
1327            .map(|i| i.parse().unwrap())
1328            .unwrap_or(100);
1329        let operations = env::var("OPERATIONS")
1330            .map(|o| o.parse().unwrap())
1331            .unwrap_or(40);
1332        let initial_entries = env::var("INITIAL_ENTRIES")
1333            .map(|o| o.parse().unwrap())
1334            .unwrap_or(20);
1335        let seeds = if let Ok(seed) = env::var("SEED").map(|s| s.parse().unwrap()) {
1336            seed..seed + 1
1337        } else {
1338            0..iterations
1339        };
1340
1341        for seed in seeds {
1342            dbg!(seed);
1343            let mut rng = StdRng::seed_from_u64(seed);
1344
1345            let root_dir = tempdir::TempDir::new(&format!("test-{}", seed)).unwrap();
1346            for _ in 0..initial_entries {
1347                randomly_mutate_tree(root_dir.path(), 1.0, &mut rng).unwrap();
1348            }
1349            log::info!("Generated initial tree");
1350
1351            let (notify_tx, _notify_rx) = smol::channel::unbounded();
1352            let mut scanner = BackgroundScanner::new(
1353                Arc::new(Mutex::new(Snapshot {
1354                    id: 0,
1355                    scan_id: 0,
1356                    abs_path: root_dir.path().into(),
1357                    entries: Default::default(),
1358                    ignores: Default::default(),
1359                    root_name_chars: Default::default(),
1360                })),
1361                Arc::new(Mutex::new(Default::default())),
1362                notify_tx,
1363                0,
1364            );
1365            scanner.scan_dirs().unwrap();
1366            scanner.snapshot().check_invariants();
1367
1368            let mut events = Vec::new();
1369            let mut mutations_len = operations;
1370            while mutations_len > 1 {
1371                if !events.is_empty() && rng.gen_bool(0.4) {
1372                    let len = rng.gen_range(0..=events.len());
1373                    let to_deliver = events.drain(0..len).collect::<Vec<_>>();
1374                    log::info!("Delivering events: {:#?}", to_deliver);
1375                    scanner.process_events(to_deliver);
1376                    scanner.snapshot().check_invariants();
1377                } else {
1378                    events.extend(randomly_mutate_tree(root_dir.path(), 0.6, &mut rng).unwrap());
1379                    mutations_len -= 1;
1380                }
1381            }
1382            log::info!("Quiescing: {:#?}", events);
1383            scanner.process_events(events);
1384            scanner.snapshot().check_invariants();
1385
1386            let (notify_tx, _notify_rx) = smol::channel::unbounded();
1387            let new_scanner = BackgroundScanner::new(
1388                Arc::new(Mutex::new(Snapshot {
1389                    id: 0,
1390                    scan_id: 0,
1391                    abs_path: root_dir.path().into(),
1392                    entries: Default::default(),
1393                    ignores: Default::default(),
1394                    root_name_chars: Default::default(),
1395                })),
1396                Arc::new(Mutex::new(Default::default())),
1397                notify_tx,
1398                1,
1399            );
1400            new_scanner.scan_dirs().unwrap();
1401            assert_eq!(scanner.snapshot().to_vec(), new_scanner.snapshot().to_vec());
1402        }
1403    }
1404
1405    fn randomly_mutate_tree(
1406        root_path: &Path,
1407        insertion_probability: f64,
1408        rng: &mut impl Rng,
1409    ) -> Result<Vec<fsevent::Event>> {
1410        let root_path = root_path.canonicalize().unwrap();
1411        let (dirs, files) = read_dir_recursive(root_path.clone());
1412
1413        let mut events = Vec::new();
1414        let mut record_event = |path: PathBuf| {
1415            events.push(fsevent::Event {
1416                event_id: SystemTime::now()
1417                    .duration_since(UNIX_EPOCH)
1418                    .unwrap()
1419                    .as_secs(),
1420                flags: fsevent::StreamFlags::empty(),
1421                path,
1422            });
1423        };
1424
1425        if (files.is_empty() && dirs.len() == 1) || rng.gen_bool(insertion_probability) {
1426            let path = dirs.choose(rng).unwrap();
1427            let new_path = path.join(gen_name(rng));
1428
1429            if rng.gen() {
1430                log::info!("Creating dir {:?}", new_path.strip_prefix(root_path)?);
1431                fs::create_dir(&new_path)?;
1432            } else {
1433                log::info!("Creating file {:?}", new_path.strip_prefix(root_path)?);
1434                fs::write(&new_path, "")?;
1435            }
1436            record_event(new_path);
1437        } else if rng.gen_bool(0.05) {
1438            let ignore_dir_path = dirs.choose(rng).unwrap();
1439            let ignore_path = ignore_dir_path.join(&*GITIGNORE);
1440
1441            let (subdirs, subfiles) = read_dir_recursive(ignore_dir_path.clone());
1442            let files_to_ignore = {
1443                let len = rng.gen_range(0..=subfiles.len());
1444                subfiles.choose_multiple(rng, len)
1445            };
1446            let dirs_to_ignore = {
1447                let len = rng.gen_range(0..subdirs.len());
1448                subdirs.choose_multiple(rng, len)
1449            };
1450
1451            let mut ignore_contents = String::new();
1452            for path_to_ignore in files_to_ignore.chain(dirs_to_ignore) {
1453                write!(
1454                    ignore_contents,
1455                    "{}\n",
1456                    path_to_ignore
1457                        .strip_prefix(&ignore_dir_path)?
1458                        .to_str()
1459                        .unwrap()
1460                )
1461                .unwrap();
1462            }
1463            log::info!(
1464                "Creating {:?} with contents:\n{}",
1465                ignore_path.strip_prefix(&root_path)?,
1466                ignore_contents
1467            );
1468            fs::write(&ignore_path, ignore_contents).unwrap();
1469            record_event(ignore_path);
1470        } else {
1471            let old_path = {
1472                let file_path = files.choose(rng);
1473                let dir_path = dirs[1..].choose(rng);
1474                file_path.into_iter().chain(dir_path).choose(rng).unwrap()
1475            };
1476
1477            let is_rename = rng.gen();
1478            if is_rename {
1479                let new_path_parent = dirs
1480                    .iter()
1481                    .filter(|d| !d.starts_with(old_path))
1482                    .choose(rng)
1483                    .unwrap();
1484
1485                let overwrite_existing_dir =
1486                    !old_path.starts_with(&new_path_parent) && rng.gen_bool(0.3);
1487                let new_path = if overwrite_existing_dir {
1488                    fs::remove_dir_all(&new_path_parent).ok();
1489                    new_path_parent.to_path_buf()
1490                } else {
1491                    new_path_parent.join(gen_name(rng))
1492                };
1493
1494                log::info!(
1495                    "Renaming {:?} to {}{:?}",
1496                    old_path.strip_prefix(&root_path)?,
1497                    if overwrite_existing_dir {
1498                        "overwrite "
1499                    } else {
1500                        ""
1501                    },
1502                    new_path.strip_prefix(&root_path)?
1503                );
1504                fs::rename(&old_path, &new_path)?;
1505                record_event(old_path.clone());
1506                record_event(new_path);
1507            } else if old_path.is_dir() {
1508                let (dirs, files) = read_dir_recursive(old_path.clone());
1509
1510                log::info!("Deleting dir {:?}", old_path.strip_prefix(&root_path)?);
1511                fs::remove_dir_all(&old_path).unwrap();
1512                for file in files {
1513                    record_event(file);
1514                }
1515                for dir in dirs {
1516                    record_event(dir);
1517                }
1518            } else {
1519                log::info!("Deleting file {:?}", old_path.strip_prefix(&root_path)?);
1520                fs::remove_file(old_path).unwrap();
1521                record_event(old_path.clone());
1522            }
1523        }
1524
1525        Ok(events)
1526    }
1527
1528    fn read_dir_recursive(path: PathBuf) -> (Vec<PathBuf>, Vec<PathBuf>) {
1529        let child_entries = fs::read_dir(&path).unwrap();
1530        let mut dirs = vec![path];
1531        let mut files = Vec::new();
1532        for child_entry in child_entries {
1533            let child_path = child_entry.unwrap().path();
1534            if child_path.is_dir() {
1535                let (child_dirs, child_files) = read_dir_recursive(child_path);
1536                dirs.extend(child_dirs);
1537                files.extend(child_files);
1538            } else {
1539                files.push(child_path);
1540            }
1541        }
1542        (dirs, files)
1543    }
1544
1545    fn gen_name(rng: &mut impl Rng) -> String {
1546        (0..6)
1547            .map(|_| rng.sample(rand::distributions::Alphanumeric))
1548            .map(char::from)
1549            .collect()
1550    }
1551
1552    impl Snapshot {
1553        fn check_invariants(&self) {
1554            let mut files = self.files(0);
1555            let mut visible_files = self.visible_files(0);
1556            for entry in self.entries.cursor::<(), ()>() {
1557                if matches!(entry.kind, EntryKind::File(_)) {
1558                    assert_eq!(files.next().unwrap().inode(), entry.inode);
1559                    if !entry.is_ignored {
1560                        assert_eq!(visible_files.next().unwrap().inode(), entry.inode);
1561                    }
1562                }
1563            }
1564            assert!(files.next().is_none());
1565            assert!(visible_files.next().is_none());
1566
1567            let mut bfs_paths = Vec::new();
1568            let mut stack = vec![Path::new("")];
1569            while let Some(path) = stack.pop() {
1570                bfs_paths.push(path);
1571                let ix = stack.len();
1572                for child_entry in self.child_entries(path) {
1573                    stack.insert(ix, child_entry.path());
1574                }
1575            }
1576
1577            let dfs_paths = self
1578                .entries
1579                .cursor::<(), ()>()
1580                .map(|e| e.path().as_ref())
1581                .collect::<Vec<_>>();
1582            assert_eq!(bfs_paths, dfs_paths);
1583
1584            for (ignore_parent_path, _) in &self.ignores {
1585                assert!(self.entry_for_path(ignore_parent_path).is_some());
1586                assert!(self
1587                    .entry_for_path(ignore_parent_path.join(&*GITIGNORE))
1588                    .is_some());
1589            }
1590        }
1591
1592        fn to_vec(&self) -> Vec<(&Path, u64, bool)> {
1593            let mut paths = Vec::new();
1594            for entry in self.entries.cursor::<(), ()>() {
1595                paths.push((entry.path().as_ref(), entry.inode(), entry.is_ignored()));
1596            }
1597            paths.sort_by(|a, b| a.0.cmp(&b.0));
1598            paths
1599        }
1600    }
1601}