1pub mod repository;
   2
   3use anyhow::{anyhow, Result};
   4pub use fsevent::Event;
   5#[cfg(target_os = "macos")]
   6use fsevent::EventStream;
   7
   8#[cfg(not(target_os = "macos"))]
   9use fsevent::StreamFlags;
  10
  11#[cfg(not(target_os = "macos"))]
  12use notify::{Config, EventKind, Watcher};
  13
  14#[cfg(unix)]
  15use std::os::unix::fs::MetadataExt;
  16
  17use async_tar::Archive;
  18use futures::{future::BoxFuture, AsyncRead, Stream, StreamExt};
  19use git2::Repository as LibGitRepository;
  20use parking_lot::Mutex;
  21use repository::GitRepository;
  22use rope::Rope;
  23use smol::io::{AsyncReadExt, AsyncWriteExt};
  24use std::io::Write;
  25use std::sync::Arc;
  26use std::{
  27    io,
  28    path::{Component, Path, PathBuf},
  29    pin::Pin,
  30    time::{Duration, SystemTime},
  31};
  32use tempfile::{NamedTempFile, TempDir};
  33use text::LineEnding;
  34use util::{paths, ResultExt};
  35
  36#[cfg(any(test, feature = "test-support"))]
  37use collections::{btree_map, BTreeMap};
  38#[cfg(any(test, feature = "test-support"))]
  39use repository::{FakeGitRepositoryState, GitFileStatus};
  40#[cfg(any(test, feature = "test-support"))]
  41use std::ffi::OsStr;
  42
  43#[async_trait::async_trait]
  44pub trait Fs: Send + Sync {
  45    async fn create_dir(&self, path: &Path) -> Result<()>;
  46    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()>;
  47    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()>;
  48    async fn create_file_with(
  49        &self,
  50        path: &Path,
  51        content: Pin<&mut (dyn AsyncRead + Send)>,
  52    ) -> Result<()>;
  53    async fn extract_tar_file(
  54        &self,
  55        path: &Path,
  56        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
  57    ) -> Result<()>;
  58    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()>;
  59    async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()>;
  60    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()>;
  61    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()>;
  62    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>>;
  63    async fn load(&self, path: &Path) -> Result<String>;
  64    async fn atomic_write(&self, path: PathBuf, text: String) -> Result<()>;
  65    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()>;
  66    async fn canonicalize(&self, path: &Path) -> Result<PathBuf>;
  67    async fn is_file(&self, path: &Path) -> bool;
  68    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>>;
  69    async fn read_link(&self, path: &Path) -> Result<PathBuf>;
  70    async fn read_dir(
  71        &self,
  72        path: &Path,
  73    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>>;
  74
  75    async fn watch(
  76        &self,
  77        path: &Path,
  78        latency: Duration,
  79    ) -> Pin<Box<dyn Send + Stream<Item = Vec<Event>>>>;
  80
  81    fn open_repo(&self, abs_dot_git: &Path) -> Option<Arc<Mutex<dyn GitRepository>>>;
  82    fn is_fake(&self) -> bool;
  83    async fn is_case_sensitive(&self) -> Result<bool>;
  84    #[cfg(any(test, feature = "test-support"))]
  85    fn as_fake(&self) -> &FakeFs;
  86}
  87
  88#[derive(Copy, Clone, Default)]
  89pub struct CreateOptions {
  90    pub overwrite: bool,
  91    pub ignore_if_exists: bool,
  92}
  93
  94#[derive(Copy, Clone, Default)]
  95pub struct CopyOptions {
  96    pub overwrite: bool,
  97    pub ignore_if_exists: bool,
  98}
  99
 100#[derive(Copy, Clone, Default)]
 101pub struct RenameOptions {
 102    pub overwrite: bool,
 103    pub ignore_if_exists: bool,
 104}
 105
 106#[derive(Copy, Clone, Default)]
 107pub struct RemoveOptions {
 108    pub recursive: bool,
 109    pub ignore_if_not_exists: bool,
 110}
 111
 112#[derive(Copy, Clone, Debug)]
 113pub struct Metadata {
 114    pub inode: u64,
 115    pub mtime: SystemTime,
 116    pub is_symlink: bool,
 117    pub is_dir: bool,
 118}
 119
 120pub struct RealFs;
 121
 122#[async_trait::async_trait]
 123impl Fs for RealFs {
 124    async fn create_dir(&self, path: &Path) -> Result<()> {
 125        Ok(smol::fs::create_dir_all(path).await?)
 126    }
 127
 128    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()> {
 129        #[cfg(target_family = "unix")]
 130        smol::fs::unix::symlink(target, path).await?;
 131
 132        #[cfg(target_family = "windows")]
 133        Err(anyhow!("not supported yet on windows"))?;
 134
 135        Ok(())
 136    }
 137
 138    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
 139        let mut open_options = smol::fs::OpenOptions::new();
 140        open_options.write(true).create(true);
 141        if options.overwrite {
 142            open_options.truncate(true);
 143        } else if !options.ignore_if_exists {
 144            open_options.create_new(true);
 145        }
 146        open_options.open(path).await?;
 147        Ok(())
 148    }
 149
 150    async fn create_file_with(
 151        &self,
 152        path: &Path,
 153        content: Pin<&mut (dyn AsyncRead + Send)>,
 154    ) -> Result<()> {
 155        let mut file = smol::fs::File::create(&path).await?;
 156        futures::io::copy(content, &mut file).await?;
 157        Ok(())
 158    }
 159
 160    async fn extract_tar_file(
 161        &self,
 162        path: &Path,
 163        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
 164    ) -> Result<()> {
 165        content.unpack(path).await?;
 166        Ok(())
 167    }
 168
 169    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()> {
 170        if !options.overwrite && smol::fs::metadata(target).await.is_ok() {
 171            if options.ignore_if_exists {
 172                return Ok(());
 173            } else {
 174                return Err(anyhow!("{target:?} already exists"));
 175            }
 176        }
 177
 178        smol::fs::copy(source, target).await?;
 179        Ok(())
 180    }
 181
 182    async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()> {
 183        if !options.overwrite && smol::fs::metadata(target).await.is_ok() {
 184            if options.ignore_if_exists {
 185                return Ok(());
 186            } else {
 187                return Err(anyhow!("{target:?} already exists"));
 188            }
 189        }
 190
 191        smol::fs::rename(source, target).await?;
 192        Ok(())
 193    }
 194
 195    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
 196        let result = if options.recursive {
 197            smol::fs::remove_dir_all(path).await
 198        } else {
 199            smol::fs::remove_dir(path).await
 200        };
 201        match result {
 202            Ok(()) => Ok(()),
 203            Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
 204                Ok(())
 205            }
 206            Err(err) => Err(err)?,
 207        }
 208    }
 209
 210    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
 211        match smol::fs::remove_file(path).await {
 212            Ok(()) => Ok(()),
 213            Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
 214                Ok(())
 215            }
 216            Err(err) => Err(err)?,
 217        }
 218    }
 219
 220    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>> {
 221        Ok(Box::new(std::fs::File::open(path)?))
 222    }
 223
 224    async fn load(&self, path: &Path) -> Result<String> {
 225        let mut file = smol::fs::File::open(path).await?;
 226        let mut text = String::new();
 227        file.read_to_string(&mut text).await?;
 228        Ok(text)
 229    }
 230
 231    async fn atomic_write(&self, path: PathBuf, data: String) -> Result<()> {
 232        smol::unblock(move || {
 233            let mut tmp_file = if cfg!(target_os = "linux") {
 234                // Use the directory of the destination as temp dir to avoid
 235                // invalid cross-device link error, and XDG_CACHE_DIR for fallback.
 236                // See https://github.com/zed-industries/zed/pull/8437 for more details.
 237                NamedTempFile::new_in(path.parent().unwrap_or(&paths::TEMP_DIR))
 238            } else {
 239                NamedTempFile::new()
 240            }?;
 241            tmp_file.write_all(data.as_bytes())?;
 242            tmp_file.persist(path)?;
 243            Ok::<(), anyhow::Error>(())
 244        })
 245        .await?;
 246
 247        Ok(())
 248    }
 249
 250    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()> {
 251        let buffer_size = text.summary().len.min(10 * 1024);
 252        if let Some(path) = path.parent() {
 253            self.create_dir(path).await?;
 254        }
 255        let file = smol::fs::File::create(path).await?;
 256        let mut writer = smol::io::BufWriter::with_capacity(buffer_size, file);
 257        for chunk in chunks(text, line_ending) {
 258            writer.write_all(chunk.as_bytes()).await?;
 259        }
 260        writer.flush().await?;
 261        Ok(())
 262    }
 263
 264    async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
 265        Ok(smol::fs::canonicalize(path).await?)
 266    }
 267
 268    async fn is_file(&self, path: &Path) -> bool {
 269        smol::fs::metadata(path)
 270            .await
 271            .map_or(false, |metadata| metadata.is_file())
 272    }
 273
 274    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
 275        let symlink_metadata = match smol::fs::symlink_metadata(path).await {
 276            Ok(metadata) => metadata,
 277            Err(err) => {
 278                return match (err.kind(), err.raw_os_error()) {
 279                    (io::ErrorKind::NotFound, _) => Ok(None),
 280                    (io::ErrorKind::Other, Some(libc::ENOTDIR)) => Ok(None),
 281                    _ => Err(anyhow::Error::new(err)),
 282                }
 283            }
 284        };
 285
 286        let is_symlink = symlink_metadata.file_type().is_symlink();
 287        let metadata = if is_symlink {
 288            smol::fs::metadata(path).await?
 289        } else {
 290            symlink_metadata
 291        };
 292
 293        #[cfg(unix)]
 294        let inode = metadata.ino();
 295
 296        #[cfg(windows)]
 297        let inode = file_id(path).await?;
 298
 299        Ok(Some(Metadata {
 300            inode,
 301            mtime: metadata.modified().unwrap(),
 302            is_symlink,
 303            is_dir: metadata.file_type().is_dir(),
 304        }))
 305    }
 306
 307    async fn read_link(&self, path: &Path) -> Result<PathBuf> {
 308        let path = smol::fs::read_link(path).await?;
 309        Ok(path)
 310    }
 311
 312    async fn read_dir(
 313        &self,
 314        path: &Path,
 315    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
 316        let result = smol::fs::read_dir(path).await?.map(|entry| match entry {
 317            Ok(entry) => Ok(entry.path()),
 318            Err(error) => Err(anyhow!("failed to read dir entry {:?}", error)),
 319        });
 320        Ok(Box::pin(result))
 321    }
 322
 323    #[cfg(target_os = "macos")]
 324    async fn watch(
 325        &self,
 326        path: &Path,
 327        latency: Duration,
 328    ) -> Pin<Box<dyn Send + Stream<Item = Vec<Event>>>> {
 329        let (tx, rx) = smol::channel::unbounded();
 330        let (stream, handle) = EventStream::new(&[path], latency);
 331        std::thread::spawn(move || {
 332            stream.run(move |events| smol::block_on(tx.send(events)).is_ok());
 333        });
 334        Box::pin(rx.chain(futures::stream::once(async move {
 335            drop(handle);
 336            vec![]
 337        })))
 338    }
 339
 340    #[cfg(not(target_os = "macos"))]
 341    async fn watch(
 342        &self,
 343        path: &Path,
 344        latency: Duration,
 345    ) -> Pin<Box<dyn Send + Stream<Item = Vec<Event>>>> {
 346        let (tx, rx) = smol::channel::unbounded();
 347
 348        if !path.exists() {
 349            log::error!("watch path does not exist: {}", path.display());
 350            return Box::pin(rx);
 351        }
 352
 353        let mut watcher =
 354            notify::recommended_watcher(move |res: Result<notify::Event, _>| match res {
 355                Ok(event) => {
 356                    let flags = match event.kind {
 357                        // ITEM_REMOVED is currently the only flag we care about
 358                        EventKind::Remove(_) => StreamFlags::ITEM_REMOVED,
 359                        _ => StreamFlags::NONE,
 360                    };
 361                    let events = event
 362                        .paths
 363                        .into_iter()
 364                        .map(|path| Event {
 365                            event_id: 0,
 366                            flags,
 367                            path,
 368                        })
 369                        .collect::<Vec<_>>();
 370                    let _ = tx.try_send(events);
 371                }
 372                Err(err) => {
 373                    log::error!("watch error: {}", err);
 374                }
 375            })
 376            .unwrap();
 377
 378        watcher
 379            .configure(Config::default().with_poll_interval(latency))
 380            .unwrap();
 381
 382        watcher
 383            .watch(path, notify::RecursiveMode::Recursive)
 384            .unwrap();
 385
 386        Box::pin(rx)
 387    }
 388
 389    fn open_repo(&self, dotgit_path: &Path) -> Option<Arc<Mutex<dyn GitRepository>>> {
 390        LibGitRepository::open(dotgit_path)
 391            .log_err()
 392            .map::<Arc<Mutex<dyn GitRepository>>, _>(|libgit_repository| {
 393                Arc::new(Mutex::new(libgit_repository))
 394            })
 395    }
 396
 397    fn is_fake(&self) -> bool {
 398        false
 399    }
 400
 401    /// Checks whether the file system is case sensitive by attempting to create two files
 402    /// that have the same name except for the casing.
 403    ///
 404    /// It creates both files in a temporary directory it removes at the end.
 405    async fn is_case_sensitive(&self) -> Result<bool> {
 406        let temp_dir = TempDir::new()?;
 407        let test_file_1 = temp_dir.path().join("case_sensitivity_test.tmp");
 408        let test_file_2 = temp_dir.path().join("CASE_SENSITIVITY_TEST.TMP");
 409
 410        let create_opts = CreateOptions {
 411            overwrite: false,
 412            ignore_if_exists: false,
 413        };
 414
 415        // Create file1
 416        self.create_file(&test_file_1, create_opts).await?;
 417
 418        // Now check whether it's possible to create file2
 419        let case_sensitive = match self.create_file(&test_file_2, create_opts).await {
 420            Ok(_) => Ok(true),
 421            Err(e) => {
 422                if let Some(io_error) = e.downcast_ref::<io::Error>() {
 423                    if io_error.kind() == io::ErrorKind::AlreadyExists {
 424                        Ok(false)
 425                    } else {
 426                        Err(e)
 427                    }
 428                } else {
 429                    Err(e)
 430                }
 431            }
 432        };
 433
 434        temp_dir.close()?;
 435        case_sensitive
 436    }
 437
 438    #[cfg(any(test, feature = "test-support"))]
 439    fn as_fake(&self) -> &FakeFs {
 440        panic!("called `RealFs::as_fake`")
 441    }
 442}
 443
 444pub fn fs_events_paths(events: Vec<Event>) -> Vec<PathBuf> {
 445    events.into_iter().map(|event| event.path).collect()
 446}
 447
 448#[cfg(any(test, feature = "test-support"))]
 449pub struct FakeFs {
 450    // Use an unfair lock to ensure tests are deterministic.
 451    state: Mutex<FakeFsState>,
 452    executor: gpui::BackgroundExecutor,
 453}
 454
 455#[cfg(any(test, feature = "test-support"))]
 456struct FakeFsState {
 457    root: Arc<Mutex<FakeFsEntry>>,
 458    next_inode: u64,
 459    next_mtime: SystemTime,
 460    event_txs: Vec<smol::channel::Sender<Vec<fsevent::Event>>>,
 461    events_paused: bool,
 462    buffered_events: Vec<fsevent::Event>,
 463    metadata_call_count: usize,
 464    read_dir_call_count: usize,
 465}
 466
 467#[cfg(any(test, feature = "test-support"))]
 468#[derive(Debug)]
 469enum FakeFsEntry {
 470    File {
 471        inode: u64,
 472        mtime: SystemTime,
 473        content: Vec<u8>,
 474    },
 475    Dir {
 476        inode: u64,
 477        mtime: SystemTime,
 478        entries: BTreeMap<String, Arc<Mutex<FakeFsEntry>>>,
 479        git_repo_state: Option<Arc<Mutex<repository::FakeGitRepositoryState>>>,
 480    },
 481    Symlink {
 482        target: PathBuf,
 483    },
 484}
 485
 486#[cfg(any(test, feature = "test-support"))]
 487impl FakeFsState {
 488    fn read_path(&self, target: &Path) -> Result<Arc<Mutex<FakeFsEntry>>> {
 489        Ok(self
 490            .try_read_path(target, true)
 491            .ok_or_else(|| anyhow!("path does not exist: {}", target.display()))?
 492            .0)
 493    }
 494
 495    fn try_read_path(
 496        &self,
 497        target: &Path,
 498        follow_symlink: bool,
 499    ) -> Option<(Arc<Mutex<FakeFsEntry>>, PathBuf)> {
 500        let mut path = target.to_path_buf();
 501        let mut canonical_path = PathBuf::new();
 502        let mut entry_stack = Vec::new();
 503        'outer: loop {
 504            let mut path_components = path.components().peekable();
 505            while let Some(component) = path_components.next() {
 506                match component {
 507                    Component::Prefix(_) => panic!("prefix paths aren't supported"),
 508                    Component::RootDir => {
 509                        entry_stack.clear();
 510                        entry_stack.push(self.root.clone());
 511                        canonical_path.clear();
 512                        canonical_path.push("/");
 513                    }
 514                    Component::CurDir => {}
 515                    Component::ParentDir => {
 516                        entry_stack.pop()?;
 517                        canonical_path.pop();
 518                    }
 519                    Component::Normal(name) => {
 520                        let current_entry = entry_stack.last().cloned()?;
 521                        let current_entry = current_entry.lock();
 522                        if let FakeFsEntry::Dir { entries, .. } = &*current_entry {
 523                            let entry = entries.get(name.to_str().unwrap()).cloned()?;
 524                            if path_components.peek().is_some() || follow_symlink {
 525                                let entry = entry.lock();
 526                                if let FakeFsEntry::Symlink { target, .. } = &*entry {
 527                                    let mut target = target.clone();
 528                                    target.extend(path_components);
 529                                    path = target;
 530                                    continue 'outer;
 531                                }
 532                            }
 533                            entry_stack.push(entry.clone());
 534                            canonical_path.push(name);
 535                        } else {
 536                            return None;
 537                        }
 538                    }
 539                }
 540            }
 541            break;
 542        }
 543        Some((entry_stack.pop()?, canonical_path))
 544    }
 545
 546    fn write_path<Fn, T>(&self, path: &Path, callback: Fn) -> Result<T>
 547    where
 548        Fn: FnOnce(btree_map::Entry<String, Arc<Mutex<FakeFsEntry>>>) -> Result<T>,
 549    {
 550        let path = normalize_path(path);
 551        let filename = path
 552            .file_name()
 553            .ok_or_else(|| anyhow!("cannot overwrite the root"))?;
 554        let parent_path = path.parent().unwrap();
 555
 556        let parent = self.read_path(parent_path)?;
 557        let mut parent = parent.lock();
 558        let new_entry = parent
 559            .dir_entries(parent_path)?
 560            .entry(filename.to_str().unwrap().into());
 561        callback(new_entry)
 562    }
 563
 564    fn emit_event<I, T>(&mut self, paths: I)
 565    where
 566        I: IntoIterator<Item = T>,
 567        T: Into<PathBuf>,
 568    {
 569        self.buffered_events
 570            .extend(paths.into_iter().map(|path| fsevent::Event {
 571                event_id: 0,
 572                flags: fsevent::StreamFlags::empty(),
 573                path: path.into(),
 574            }));
 575
 576        if !self.events_paused {
 577            self.flush_events(self.buffered_events.len());
 578        }
 579    }
 580
 581    fn flush_events(&mut self, mut count: usize) {
 582        count = count.min(self.buffered_events.len());
 583        let events = self.buffered_events.drain(0..count).collect::<Vec<_>>();
 584        self.event_txs.retain(|tx| {
 585            let _ = tx.try_send(events.clone());
 586            !tx.is_closed()
 587        });
 588    }
 589}
 590
 591#[cfg(any(test, feature = "test-support"))]
 592lazy_static::lazy_static! {
 593    pub static ref FS_DOT_GIT: &'static OsStr = OsStr::new(".git");
 594}
 595
 596#[cfg(any(test, feature = "test-support"))]
 597impl FakeFs {
 598    pub fn new(executor: gpui::BackgroundExecutor) -> Arc<Self> {
 599        Arc::new(Self {
 600            executor,
 601            state: Mutex::new(FakeFsState {
 602                root: Arc::new(Mutex::new(FakeFsEntry::Dir {
 603                    inode: 0,
 604                    mtime: SystemTime::UNIX_EPOCH,
 605                    entries: Default::default(),
 606                    git_repo_state: None,
 607                })),
 608                next_mtime: SystemTime::UNIX_EPOCH,
 609                next_inode: 1,
 610                event_txs: Default::default(),
 611                buffered_events: Vec::new(),
 612                events_paused: false,
 613                read_dir_call_count: 0,
 614                metadata_call_count: 0,
 615            }),
 616        })
 617    }
 618
 619    pub async fn insert_file(&self, path: impl AsRef<Path>, content: Vec<u8>) {
 620        self.write_file_internal(path, content).unwrap()
 621    }
 622
 623    pub async fn insert_symlink(&self, path: impl AsRef<Path>, target: PathBuf) {
 624        let mut state = self.state.lock();
 625        let path = path.as_ref();
 626        let file = Arc::new(Mutex::new(FakeFsEntry::Symlink { target }));
 627        state
 628            .write_path(path.as_ref(), move |e| match e {
 629                btree_map::Entry::Vacant(e) => {
 630                    e.insert(file);
 631                    Ok(())
 632                }
 633                btree_map::Entry::Occupied(mut e) => {
 634                    *e.get_mut() = file;
 635                    Ok(())
 636                }
 637            })
 638            .unwrap();
 639        state.emit_event([path]);
 640    }
 641
 642    fn write_file_internal(&self, path: impl AsRef<Path>, content: Vec<u8>) -> Result<()> {
 643        let mut state = self.state.lock();
 644        let path = path.as_ref();
 645        let inode = state.next_inode;
 646        let mtime = state.next_mtime;
 647        state.next_inode += 1;
 648        state.next_mtime += Duration::from_nanos(1);
 649        let file = Arc::new(Mutex::new(FakeFsEntry::File {
 650            inode,
 651            mtime,
 652            content,
 653        }));
 654        state.write_path(path, move |entry| {
 655            match entry {
 656                btree_map::Entry::Vacant(e) => {
 657                    e.insert(file);
 658                }
 659                btree_map::Entry::Occupied(mut e) => {
 660                    *e.get_mut() = file;
 661                }
 662            }
 663            Ok(())
 664        })?;
 665        state.emit_event([path]);
 666        Ok(())
 667    }
 668
 669    async fn load_internal(&self, path: impl AsRef<Path>) -> Result<Vec<u8>> {
 670        let path = path.as_ref();
 671        let path = normalize_path(path);
 672        self.simulate_random_delay().await;
 673        let state = self.state.lock();
 674        let entry = state.read_path(&path)?;
 675        let entry = entry.lock();
 676        entry.file_content(&path).cloned()
 677    }
 678
 679    pub fn pause_events(&self) {
 680        self.state.lock().events_paused = true;
 681    }
 682
 683    pub fn buffered_event_count(&self) -> usize {
 684        self.state.lock().buffered_events.len()
 685    }
 686
 687    pub fn flush_events(&self, count: usize) {
 688        self.state.lock().flush_events(count);
 689    }
 690
 691    #[must_use]
 692    pub fn insert_tree<'a>(
 693        &'a self,
 694        path: impl 'a + AsRef<Path> + Send,
 695        tree: serde_json::Value,
 696    ) -> futures::future::BoxFuture<'a, ()> {
 697        use futures::FutureExt as _;
 698        use serde_json::Value::*;
 699
 700        async move {
 701            let path = path.as_ref();
 702
 703            match tree {
 704                Object(map) => {
 705                    self.create_dir(path).await.unwrap();
 706                    for (name, contents) in map {
 707                        let mut path = PathBuf::from(path);
 708                        path.push(name);
 709                        self.insert_tree(&path, contents).await;
 710                    }
 711                }
 712                Null => {
 713                    self.create_dir(path).await.unwrap();
 714                }
 715                String(contents) => {
 716                    self.insert_file(&path, contents.into_bytes()).await;
 717                }
 718                _ => {
 719                    panic!("JSON object must contain only objects, strings, or null");
 720                }
 721            }
 722        }
 723        .boxed()
 724    }
 725
 726    pub fn insert_tree_from_real_fs<'a>(
 727        &'a self,
 728        path: impl 'a + AsRef<Path> + Send,
 729        src_path: impl 'a + AsRef<Path> + Send,
 730    ) -> futures::future::BoxFuture<'a, ()> {
 731        use futures::FutureExt as _;
 732
 733        async move {
 734            let path = path.as_ref();
 735            if std::fs::metadata(&src_path).unwrap().is_file() {
 736                let contents = std::fs::read(src_path).unwrap();
 737                self.insert_file(path, contents).await;
 738            } else {
 739                self.create_dir(path).await.unwrap();
 740                for entry in std::fs::read_dir(&src_path).unwrap() {
 741                    let entry = entry.unwrap();
 742                    self.insert_tree_from_real_fs(&path.join(entry.file_name()), &entry.path())
 743                        .await;
 744                }
 745            }
 746        }
 747        .boxed()
 748    }
 749
 750    pub fn with_git_state<F>(&self, dot_git: &Path, emit_git_event: bool, f: F)
 751    where
 752        F: FnOnce(&mut FakeGitRepositoryState),
 753    {
 754        let mut state = self.state.lock();
 755        let entry = state.read_path(dot_git).unwrap();
 756        let mut entry = entry.lock();
 757
 758        if let FakeFsEntry::Dir { git_repo_state, .. } = &mut *entry {
 759            let repo_state = git_repo_state.get_or_insert_with(Default::default);
 760            let mut repo_state = repo_state.lock();
 761
 762            f(&mut repo_state);
 763
 764            if emit_git_event {
 765                state.emit_event([dot_git]);
 766            }
 767        } else {
 768            panic!("not a directory");
 769        }
 770    }
 771
 772    pub fn set_branch_name(&self, dot_git: &Path, branch: Option<impl Into<String>>) {
 773        self.with_git_state(dot_git, true, |state| {
 774            state.branch_name = branch.map(Into::into)
 775        })
 776    }
 777
 778    pub fn set_index_for_repo(&self, dot_git: &Path, head_state: &[(&Path, String)]) {
 779        self.with_git_state(dot_git, true, |state| {
 780            state.index_contents.clear();
 781            state.index_contents.extend(
 782                head_state
 783                    .iter()
 784                    .map(|(path, content)| (path.to_path_buf(), content.clone())),
 785            );
 786        });
 787    }
 788
 789    pub fn set_status_for_repo_via_working_copy_change(
 790        &self,
 791        dot_git: &Path,
 792        statuses: &[(&Path, GitFileStatus)],
 793    ) {
 794        self.with_git_state(dot_git, false, |state| {
 795            state.worktree_statuses.clear();
 796            state.worktree_statuses.extend(
 797                statuses
 798                    .iter()
 799                    .map(|(path, content)| ((**path).into(), *content)),
 800            );
 801        });
 802        self.state.lock().emit_event(
 803            statuses
 804                .iter()
 805                .map(|(path, _)| dot_git.parent().unwrap().join(path)),
 806        );
 807    }
 808
 809    pub fn set_status_for_repo_via_git_operation(
 810        &self,
 811        dot_git: &Path,
 812        statuses: &[(&Path, GitFileStatus)],
 813    ) {
 814        self.with_git_state(dot_git, true, |state| {
 815            state.worktree_statuses.clear();
 816            state.worktree_statuses.extend(
 817                statuses
 818                    .iter()
 819                    .map(|(path, content)| ((**path).into(), *content)),
 820            );
 821        });
 822    }
 823
 824    pub fn paths(&self, include_dot_git: bool) -> Vec<PathBuf> {
 825        let mut result = Vec::new();
 826        let mut queue = collections::VecDeque::new();
 827        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 828        while let Some((path, entry)) = queue.pop_front() {
 829            if let FakeFsEntry::Dir { entries, .. } = &*entry.lock() {
 830                for (name, entry) in entries {
 831                    queue.push_back((path.join(name), entry.clone()));
 832                }
 833            }
 834            if include_dot_git
 835                || !path
 836                    .components()
 837                    .any(|component| component.as_os_str() == *FS_DOT_GIT)
 838            {
 839                result.push(path);
 840            }
 841        }
 842        result
 843    }
 844
 845    pub fn directories(&self, include_dot_git: bool) -> Vec<PathBuf> {
 846        let mut result = Vec::new();
 847        let mut queue = collections::VecDeque::new();
 848        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 849        while let Some((path, entry)) = queue.pop_front() {
 850            if let FakeFsEntry::Dir { entries, .. } = &*entry.lock() {
 851                for (name, entry) in entries {
 852                    queue.push_back((path.join(name), entry.clone()));
 853                }
 854                if include_dot_git
 855                    || !path
 856                        .components()
 857                        .any(|component| component.as_os_str() == *FS_DOT_GIT)
 858                {
 859                    result.push(path);
 860                }
 861            }
 862        }
 863        result
 864    }
 865
 866    pub fn files(&self) -> Vec<PathBuf> {
 867        let mut result = Vec::new();
 868        let mut queue = collections::VecDeque::new();
 869        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 870        while let Some((path, entry)) = queue.pop_front() {
 871            let e = entry.lock();
 872            match &*e {
 873                FakeFsEntry::File { .. } => result.push(path),
 874                FakeFsEntry::Dir { entries, .. } => {
 875                    for (name, entry) in entries {
 876                        queue.push_back((path.join(name), entry.clone()));
 877                    }
 878                }
 879                FakeFsEntry::Symlink { .. } => {}
 880            }
 881        }
 882        result
 883    }
 884
 885    /// How many `read_dir` calls have been issued.
 886    pub fn read_dir_call_count(&self) -> usize {
 887        self.state.lock().read_dir_call_count
 888    }
 889
 890    /// How many `metadata` calls have been issued.
 891    pub fn metadata_call_count(&self) -> usize {
 892        self.state.lock().metadata_call_count
 893    }
 894
 895    fn simulate_random_delay(&self) -> impl futures::Future<Output = ()> {
 896        self.executor.simulate_random_delay()
 897    }
 898}
 899
 900#[cfg(any(test, feature = "test-support"))]
 901impl FakeFsEntry {
 902    fn is_file(&self) -> bool {
 903        matches!(self, Self::File { .. })
 904    }
 905
 906    fn is_symlink(&self) -> bool {
 907        matches!(self, Self::Symlink { .. })
 908    }
 909
 910    fn file_content(&self, path: &Path) -> Result<&Vec<u8>> {
 911        if let Self::File { content, .. } = self {
 912            Ok(content)
 913        } else {
 914            Err(anyhow!("not a file: {}", path.display()))
 915        }
 916    }
 917
 918    fn set_file_content(&mut self, path: &Path, new_content: Vec<u8>) -> Result<()> {
 919        if let Self::File { content, mtime, .. } = self {
 920            *mtime = SystemTime::now();
 921            *content = new_content;
 922            Ok(())
 923        } else {
 924            Err(anyhow!("not a file: {}", path.display()))
 925        }
 926    }
 927
 928    fn dir_entries(
 929        &mut self,
 930        path: &Path,
 931    ) -> Result<&mut BTreeMap<String, Arc<Mutex<FakeFsEntry>>>> {
 932        if let Self::Dir { entries, .. } = self {
 933            Ok(entries)
 934        } else {
 935            Err(anyhow!("not a directory: {}", path.display()))
 936        }
 937    }
 938}
 939
 940#[cfg(any(test, feature = "test-support"))]
 941#[async_trait::async_trait]
 942impl Fs for FakeFs {
 943    async fn create_dir(&self, path: &Path) -> Result<()> {
 944        self.simulate_random_delay().await;
 945
 946        let mut created_dirs = Vec::new();
 947        let mut cur_path = PathBuf::new();
 948        for component in path.components() {
 949            let mut state = self.state.lock();
 950            cur_path.push(component);
 951            if cur_path == Path::new("/") {
 952                continue;
 953            }
 954
 955            let inode = state.next_inode;
 956            let mtime = state.next_mtime;
 957            state.next_mtime += Duration::from_nanos(1);
 958            state.next_inode += 1;
 959            state.write_path(&cur_path, |entry| {
 960                entry.or_insert_with(|| {
 961                    created_dirs.push(cur_path.clone());
 962                    Arc::new(Mutex::new(FakeFsEntry::Dir {
 963                        inode,
 964                        mtime,
 965                        entries: Default::default(),
 966                        git_repo_state: None,
 967                    }))
 968                });
 969                Ok(())
 970            })?
 971        }
 972
 973        self.state.lock().emit_event(&created_dirs);
 974        Ok(())
 975    }
 976
 977    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
 978        self.simulate_random_delay().await;
 979        let mut state = self.state.lock();
 980        let inode = state.next_inode;
 981        let mtime = state.next_mtime;
 982        state.next_mtime += Duration::from_nanos(1);
 983        state.next_inode += 1;
 984        let file = Arc::new(Mutex::new(FakeFsEntry::File {
 985            inode,
 986            mtime,
 987            content: Vec::new(),
 988        }));
 989        state.write_path(path, |entry| {
 990            match entry {
 991                btree_map::Entry::Occupied(mut e) => {
 992                    if options.overwrite {
 993                        *e.get_mut() = file;
 994                    } else if !options.ignore_if_exists {
 995                        return Err(anyhow!("path already exists: {}", path.display()));
 996                    }
 997                }
 998                btree_map::Entry::Vacant(e) => {
 999                    e.insert(file);
1000                }
1001            }
1002            Ok(())
1003        })?;
1004        state.emit_event([path]);
1005        Ok(())
1006    }
1007
1008    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()> {
1009        let mut state = self.state.lock();
1010        let file = Arc::new(Mutex::new(FakeFsEntry::Symlink { target }));
1011        state
1012            .write_path(path.as_ref(), move |e| match e {
1013                btree_map::Entry::Vacant(e) => {
1014                    e.insert(file);
1015                    Ok(())
1016                }
1017                btree_map::Entry::Occupied(mut e) => {
1018                    *e.get_mut() = file;
1019                    Ok(())
1020                }
1021            })
1022            .unwrap();
1023        state.emit_event(&[path]);
1024        Ok(())
1025    }
1026
1027    async fn create_file_with(
1028        &self,
1029        path: &Path,
1030        mut content: Pin<&mut (dyn AsyncRead + Send)>,
1031    ) -> Result<()> {
1032        let mut bytes = Vec::new();
1033        content.read_to_end(&mut bytes).await?;
1034        self.write_file_internal(path, bytes)?;
1035        Ok(())
1036    }
1037
1038    async fn extract_tar_file(
1039        &self,
1040        path: &Path,
1041        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
1042    ) -> Result<()> {
1043        let mut entries = content.entries()?;
1044        while let Some(entry) = entries.next().await {
1045            let mut entry = entry?;
1046            if entry.header().entry_type().is_file() {
1047                let path = path.join(entry.path()?.as_ref());
1048                let mut bytes = Vec::new();
1049                entry.read_to_end(&mut bytes).await?;
1050                self.create_dir(path.parent().unwrap()).await?;
1051                self.write_file_internal(&path, bytes)?;
1052            }
1053        }
1054        Ok(())
1055    }
1056
1057    async fn rename(&self, old_path: &Path, new_path: &Path, options: RenameOptions) -> Result<()> {
1058        self.simulate_random_delay().await;
1059
1060        let old_path = normalize_path(old_path);
1061        let new_path = normalize_path(new_path);
1062
1063        let mut state = self.state.lock();
1064        let moved_entry = state.write_path(&old_path, |e| {
1065            if let btree_map::Entry::Occupied(e) = e {
1066                Ok(e.get().clone())
1067            } else {
1068                Err(anyhow!("path does not exist: {}", &old_path.display()))
1069            }
1070        })?;
1071
1072        state.write_path(&new_path, |e| {
1073            match e {
1074                btree_map::Entry::Occupied(mut e) => {
1075                    if options.overwrite {
1076                        *e.get_mut() = moved_entry;
1077                    } else if !options.ignore_if_exists {
1078                        return Err(anyhow!("path already exists: {}", new_path.display()));
1079                    }
1080                }
1081                btree_map::Entry::Vacant(e) => {
1082                    e.insert(moved_entry);
1083                }
1084            }
1085            Ok(())
1086        })?;
1087
1088        state
1089            .write_path(&old_path, |e| {
1090                if let btree_map::Entry::Occupied(e) = e {
1091                    Ok(e.remove())
1092                } else {
1093                    unreachable!()
1094                }
1095            })
1096            .unwrap();
1097
1098        state.emit_event(&[old_path, new_path]);
1099        Ok(())
1100    }
1101
1102    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()> {
1103        self.simulate_random_delay().await;
1104
1105        let source = normalize_path(source);
1106        let target = normalize_path(target);
1107        let mut state = self.state.lock();
1108        let mtime = state.next_mtime;
1109        let inode = util::post_inc(&mut state.next_inode);
1110        state.next_mtime += Duration::from_nanos(1);
1111        let source_entry = state.read_path(&source)?;
1112        let content = source_entry.lock().file_content(&source)?.clone();
1113        let entry = state.write_path(&target, |e| match e {
1114            btree_map::Entry::Occupied(e) => {
1115                if options.overwrite {
1116                    Ok(Some(e.get().clone()))
1117                } else if !options.ignore_if_exists {
1118                    return Err(anyhow!("{target:?} already exists"));
1119                } else {
1120                    Ok(None)
1121                }
1122            }
1123            btree_map::Entry::Vacant(e) => Ok(Some(
1124                e.insert(Arc::new(Mutex::new(FakeFsEntry::File {
1125                    inode,
1126                    mtime,
1127                    content: Vec::new(),
1128                })))
1129                .clone(),
1130            )),
1131        })?;
1132        if let Some(entry) = entry {
1133            entry.lock().set_file_content(&target, content)?;
1134        }
1135        state.emit_event(&[target]);
1136        Ok(())
1137    }
1138
1139    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
1140        self.simulate_random_delay().await;
1141
1142        let path = normalize_path(path);
1143        let parent_path = path
1144            .parent()
1145            .ok_or_else(|| anyhow!("cannot remove the root"))?;
1146        let base_name = path.file_name().unwrap();
1147
1148        let mut state = self.state.lock();
1149        let parent_entry = state.read_path(parent_path)?;
1150        let mut parent_entry = parent_entry.lock();
1151        let entry = parent_entry
1152            .dir_entries(parent_path)?
1153            .entry(base_name.to_str().unwrap().into());
1154
1155        match entry {
1156            btree_map::Entry::Vacant(_) => {
1157                if !options.ignore_if_not_exists {
1158                    return Err(anyhow!("{path:?} does not exist"));
1159                }
1160            }
1161            btree_map::Entry::Occupied(e) => {
1162                {
1163                    let mut entry = e.get().lock();
1164                    let children = entry.dir_entries(&path)?;
1165                    if !options.recursive && !children.is_empty() {
1166                        return Err(anyhow!("{path:?} is not empty"));
1167                    }
1168                }
1169                e.remove();
1170            }
1171        }
1172        state.emit_event(&[path]);
1173        Ok(())
1174    }
1175
1176    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
1177        self.simulate_random_delay().await;
1178
1179        let path = normalize_path(path);
1180        let parent_path = path
1181            .parent()
1182            .ok_or_else(|| anyhow!("cannot remove the root"))?;
1183        let base_name = path.file_name().unwrap();
1184        let mut state = self.state.lock();
1185        let parent_entry = state.read_path(parent_path)?;
1186        let mut parent_entry = parent_entry.lock();
1187        let entry = parent_entry
1188            .dir_entries(parent_path)?
1189            .entry(base_name.to_str().unwrap().into());
1190        match entry {
1191            btree_map::Entry::Vacant(_) => {
1192                if !options.ignore_if_not_exists {
1193                    return Err(anyhow!("{path:?} does not exist"));
1194                }
1195            }
1196            btree_map::Entry::Occupied(e) => {
1197                e.get().lock().file_content(&path)?;
1198                e.remove();
1199            }
1200        }
1201        state.emit_event(&[path]);
1202        Ok(())
1203    }
1204
1205    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>> {
1206        let bytes = self.load_internal(path).await?;
1207        Ok(Box::new(io::Cursor::new(bytes)))
1208    }
1209
1210    async fn load(&self, path: &Path) -> Result<String> {
1211        let content = self.load_internal(path).await?;
1212        Ok(String::from_utf8(content.clone())?)
1213    }
1214
1215    async fn atomic_write(&self, path: PathBuf, data: String) -> Result<()> {
1216        self.simulate_random_delay().await;
1217        let path = normalize_path(path.as_path());
1218        self.write_file_internal(path, data.into_bytes())?;
1219        Ok(())
1220    }
1221
1222    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()> {
1223        self.simulate_random_delay().await;
1224        let path = normalize_path(path);
1225        let content = chunks(text, line_ending).collect::<String>();
1226        if let Some(path) = path.parent() {
1227            self.create_dir(path).await?;
1228        }
1229        self.write_file_internal(path, content.into_bytes())?;
1230        Ok(())
1231    }
1232
1233    async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
1234        let path = normalize_path(path);
1235        self.simulate_random_delay().await;
1236        let state = self.state.lock();
1237        if let Some((_, canonical_path)) = state.try_read_path(&path, true) {
1238            Ok(canonical_path)
1239        } else {
1240            Err(anyhow!("path does not exist: {}", path.display()))
1241        }
1242    }
1243
1244    async fn is_file(&self, path: &Path) -> bool {
1245        let path = normalize_path(path);
1246        self.simulate_random_delay().await;
1247        let state = self.state.lock();
1248        if let Some((entry, _)) = state.try_read_path(&path, true) {
1249            entry.lock().is_file()
1250        } else {
1251            false
1252        }
1253    }
1254
1255    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
1256        self.simulate_random_delay().await;
1257        let path = normalize_path(path);
1258        let mut state = self.state.lock();
1259        state.metadata_call_count += 1;
1260        if let Some((mut entry, _)) = state.try_read_path(&path, false) {
1261            let is_symlink = entry.lock().is_symlink();
1262            if is_symlink {
1263                if let Some(e) = state.try_read_path(&path, true).map(|e| e.0) {
1264                    entry = e;
1265                } else {
1266                    return Ok(None);
1267                }
1268            }
1269
1270            let entry = entry.lock();
1271            Ok(Some(match &*entry {
1272                FakeFsEntry::File { inode, mtime, .. } => Metadata {
1273                    inode: *inode,
1274                    mtime: *mtime,
1275                    is_dir: false,
1276                    is_symlink,
1277                },
1278                FakeFsEntry::Dir { inode, mtime, .. } => Metadata {
1279                    inode: *inode,
1280                    mtime: *mtime,
1281                    is_dir: true,
1282                    is_symlink,
1283                },
1284                FakeFsEntry::Symlink { .. } => unreachable!(),
1285            }))
1286        } else {
1287            Ok(None)
1288        }
1289    }
1290
1291    async fn read_link(&self, path: &Path) -> Result<PathBuf> {
1292        self.simulate_random_delay().await;
1293        let path = normalize_path(path);
1294        let state = self.state.lock();
1295        if let Some((entry, _)) = state.try_read_path(&path, false) {
1296            let entry = entry.lock();
1297            if let FakeFsEntry::Symlink { target } = &*entry {
1298                Ok(target.clone())
1299            } else {
1300                Err(anyhow!("not a symlink: {}", path.display()))
1301            }
1302        } else {
1303            Err(anyhow!("path does not exist: {}", path.display()))
1304        }
1305    }
1306
1307    async fn read_dir(
1308        &self,
1309        path: &Path,
1310    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
1311        self.simulate_random_delay().await;
1312        let path = normalize_path(path);
1313        let mut state = self.state.lock();
1314        state.read_dir_call_count += 1;
1315        let entry = state.read_path(&path)?;
1316        let mut entry = entry.lock();
1317        let children = entry.dir_entries(&path)?;
1318        let paths = children
1319            .keys()
1320            .map(|file_name| Ok(path.join(file_name)))
1321            .collect::<Vec<_>>();
1322        Ok(Box::pin(futures::stream::iter(paths)))
1323    }
1324
1325    async fn watch(
1326        &self,
1327        path: &Path,
1328        _: Duration,
1329    ) -> Pin<Box<dyn Send + Stream<Item = Vec<fsevent::Event>>>> {
1330        self.simulate_random_delay().await;
1331        let (tx, rx) = smol::channel::unbounded();
1332        self.state.lock().event_txs.push(tx);
1333        let path = path.to_path_buf();
1334        let executor = self.executor.clone();
1335        Box::pin(futures::StreamExt::filter(rx, move |events| {
1336            let result = events.iter().any(|event| event.path.starts_with(&path));
1337            let executor = executor.clone();
1338            async move {
1339                executor.simulate_random_delay().await;
1340                result
1341            }
1342        }))
1343    }
1344
1345    fn open_repo(&self, abs_dot_git: &Path) -> Option<Arc<Mutex<dyn GitRepository>>> {
1346        let state = self.state.lock();
1347        let entry = state.read_path(abs_dot_git).unwrap();
1348        let mut entry = entry.lock();
1349        if let FakeFsEntry::Dir { git_repo_state, .. } = &mut *entry {
1350            let state = git_repo_state
1351                .get_or_insert_with(|| Arc::new(Mutex::new(FakeGitRepositoryState::default())))
1352                .clone();
1353            Some(repository::FakeGitRepository::open(state))
1354        } else {
1355            None
1356        }
1357    }
1358
1359    fn is_fake(&self) -> bool {
1360        true
1361    }
1362
1363    async fn is_case_sensitive(&self) -> Result<bool> {
1364        Ok(true)
1365    }
1366
1367    #[cfg(any(test, feature = "test-support"))]
1368    fn as_fake(&self) -> &FakeFs {
1369        self
1370    }
1371}
1372
1373fn chunks(rope: &Rope, line_ending: LineEnding) -> impl Iterator<Item = &str> {
1374    rope.chunks().flat_map(move |chunk| {
1375        let mut newline = false;
1376        chunk.split('\n').flat_map(move |line| {
1377            let ending = if newline {
1378                Some(line_ending.as_str())
1379            } else {
1380                None
1381            };
1382            newline = true;
1383            ending.into_iter().chain([line])
1384        })
1385    })
1386}
1387
1388pub fn normalize_path(path: &Path) -> PathBuf {
1389    let mut components = path.components().peekable();
1390    let mut ret = if let Some(c @ Component::Prefix(..)) = components.peek().cloned() {
1391        components.next();
1392        PathBuf::from(c.as_os_str())
1393    } else {
1394        PathBuf::new()
1395    };
1396
1397    for component in components {
1398        match component {
1399            Component::Prefix(..) => unreachable!(),
1400            Component::RootDir => {
1401                ret.push(component.as_os_str());
1402            }
1403            Component::CurDir => {}
1404            Component::ParentDir => {
1405                ret.pop();
1406            }
1407            Component::Normal(c) => {
1408                ret.push(c);
1409            }
1410        }
1411    }
1412    ret
1413}
1414
1415pub fn copy_recursive<'a>(
1416    fs: &'a dyn Fs,
1417    source: &'a Path,
1418    target: &'a Path,
1419    options: CopyOptions,
1420) -> BoxFuture<'a, Result<()>> {
1421    use futures::future::FutureExt;
1422
1423    async move {
1424        let metadata = fs
1425            .metadata(source)
1426            .await?
1427            .ok_or_else(|| anyhow!("path does not exist: {}", source.display()))?;
1428        if metadata.is_dir {
1429            if !options.overwrite && fs.metadata(target).await.is_ok_and(|m| m.is_some()) {
1430                if options.ignore_if_exists {
1431                    return Ok(());
1432                } else {
1433                    return Err(anyhow!("{target:?} already exists"));
1434                }
1435            }
1436
1437            let _ = fs
1438                .remove_dir(
1439                    target,
1440                    RemoveOptions {
1441                        recursive: true,
1442                        ignore_if_not_exists: true,
1443                    },
1444                )
1445                .await;
1446            fs.create_dir(target).await?;
1447            let mut children = fs.read_dir(source).await?;
1448            while let Some(child_path) = children.next().await {
1449                if let Ok(child_path) = child_path {
1450                    if let Some(file_name) = child_path.file_name() {
1451                        let child_target_path = target.join(file_name);
1452                        copy_recursive(fs, &child_path, &child_target_path, options).await?;
1453                    }
1454                }
1455            }
1456
1457            Ok(())
1458        } else {
1459            fs.copy_file(source, target, options).await
1460        }
1461    }
1462    .boxed()
1463}
1464
1465// todo(windows)
1466// can we get file id not open the file twice?
1467// https://github.com/rust-lang/rust/issues/63010
1468#[cfg(target_os = "windows")]
1469async fn file_id(path: impl AsRef<Path>) -> Result<u64> {
1470    use std::os::windows::io::AsRawHandle;
1471
1472    use smol::fs::windows::OpenOptionsExt;
1473    use windows_sys::Win32::{
1474        Foundation::HANDLE,
1475        Storage::FileSystem::{
1476            GetFileInformationByHandle, BY_HANDLE_FILE_INFORMATION, FILE_FLAG_BACKUP_SEMANTICS,
1477        },
1478    };
1479
1480    let file = smol::fs::OpenOptions::new()
1481        .read(true)
1482        .custom_flags(FILE_FLAG_BACKUP_SEMANTICS)
1483        .open(path)
1484        .await?;
1485
1486    let mut info: BY_HANDLE_FILE_INFORMATION = unsafe { std::mem::zeroed() };
1487    // https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfileinformationbyhandle
1488    // This function supports Windows XP+
1489    smol::unblock(move || {
1490        let ret = unsafe { GetFileInformationByHandle(file.as_raw_handle() as HANDLE, &mut info) };
1491        if ret == 0 {
1492            return Err(anyhow!(format!("{}", std::io::Error::last_os_error())));
1493        };
1494
1495        Ok(((info.nFileIndexHigh as u64) << 32) | (info.nFileIndexLow as u64))
1496    })
1497    .await
1498}
1499
1500#[cfg(test)]
1501mod tests {
1502    use super::*;
1503    use gpui::BackgroundExecutor;
1504    use serde_json::json;
1505
1506    #[gpui::test]
1507    async fn test_fake_fs(executor: BackgroundExecutor) {
1508        let fs = FakeFs::new(executor.clone());
1509        fs.insert_tree(
1510            "/root",
1511            json!({
1512                "dir1": {
1513                    "a": "A",
1514                    "b": "B"
1515                },
1516                "dir2": {
1517                    "c": "C",
1518                    "dir3": {
1519                        "d": "D"
1520                    }
1521                }
1522            }),
1523        )
1524        .await;
1525
1526        assert_eq!(
1527            fs.files(),
1528            vec![
1529                PathBuf::from("/root/dir1/a"),
1530                PathBuf::from("/root/dir1/b"),
1531                PathBuf::from("/root/dir2/c"),
1532                PathBuf::from("/root/dir2/dir3/d"),
1533            ]
1534        );
1535
1536        fs.create_symlink("/root/dir2/link-to-dir3".as_ref(), "./dir3".into())
1537            .await
1538            .unwrap();
1539
1540        assert_eq!(
1541            fs.canonicalize("/root/dir2/link-to-dir3".as_ref())
1542                .await
1543                .unwrap(),
1544            PathBuf::from("/root/dir2/dir3"),
1545        );
1546        assert_eq!(
1547            fs.canonicalize("/root/dir2/link-to-dir3/d".as_ref())
1548                .await
1549                .unwrap(),
1550            PathBuf::from("/root/dir2/dir3/d"),
1551        );
1552        assert_eq!(
1553            fs.load("/root/dir2/link-to-dir3/d".as_ref()).await.unwrap(),
1554            "D",
1555        );
1556    }
1557}