1pub mod repository;
   2
   3use anyhow::{anyhow, Result};
   4
   5#[cfg(unix)]
   6use std::os::unix::fs::MetadataExt;
   7
   8use async_tar::Archive;
   9use futures::{future::BoxFuture, AsyncRead, Stream, StreamExt};
  10use git2::Repository as LibGitRepository;
  11use parking_lot::Mutex;
  12use repository::GitRepository;
  13use rope::Rope;
  14use smol::io::{AsyncReadExt, AsyncWriteExt};
  15use std::io::Write;
  16use std::sync::Arc;
  17use std::{
  18    io,
  19    path::{Component, Path, PathBuf},
  20    pin::Pin,
  21    time::{Duration, SystemTime},
  22};
  23use tempfile::{NamedTempFile, TempDir};
  24use text::LineEnding;
  25use util::{paths, ResultExt};
  26
  27#[cfg(any(test, feature = "test-support"))]
  28use collections::{btree_map, BTreeMap};
  29#[cfg(any(test, feature = "test-support"))]
  30use repository::{FakeGitRepositoryState, GitFileStatus};
  31#[cfg(any(test, feature = "test-support"))]
  32use std::ffi::OsStr;
  33
  34#[async_trait::async_trait]
  35pub trait Fs: Send + Sync {
  36    async fn create_dir(&self, path: &Path) -> Result<()>;
  37    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()>;
  38    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()>;
  39    async fn create_file_with(
  40        &self,
  41        path: &Path,
  42        content: Pin<&mut (dyn AsyncRead + Send)>,
  43    ) -> Result<()>;
  44    async fn extract_tar_file(
  45        &self,
  46        path: &Path,
  47        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
  48    ) -> Result<()>;
  49    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()>;
  50    async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()>;
  51    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()>;
  52    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()>;
  53    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>>;
  54    async fn load(&self, path: &Path) -> Result<String>;
  55    async fn atomic_write(&self, path: PathBuf, text: String) -> Result<()>;
  56    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()>;
  57    async fn canonicalize(&self, path: &Path) -> Result<PathBuf>;
  58    async fn is_file(&self, path: &Path) -> bool;
  59    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>>;
  60    async fn read_link(&self, path: &Path) -> Result<PathBuf>;
  61    async fn read_dir(
  62        &self,
  63        path: &Path,
  64    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>>;
  65
  66    async fn watch(
  67        &self,
  68        path: &Path,
  69        latency: Duration,
  70    ) -> Pin<Box<dyn Send + Stream<Item = Vec<PathBuf>>>>;
  71
  72    fn open_repo(&self, abs_dot_git: &Path) -> Option<Arc<Mutex<dyn GitRepository>>>;
  73    fn is_fake(&self) -> bool;
  74    async fn is_case_sensitive(&self) -> Result<bool>;
  75    #[cfg(any(test, feature = "test-support"))]
  76    fn as_fake(&self) -> &FakeFs;
  77}
  78
  79#[derive(Copy, Clone, Default)]
  80pub struct CreateOptions {
  81    pub overwrite: bool,
  82    pub ignore_if_exists: bool,
  83}
  84
  85#[derive(Copy, Clone, Default)]
  86pub struct CopyOptions {
  87    pub overwrite: bool,
  88    pub ignore_if_exists: bool,
  89}
  90
  91#[derive(Copy, Clone, Default)]
  92pub struct RenameOptions {
  93    pub overwrite: bool,
  94    pub ignore_if_exists: bool,
  95}
  96
  97#[derive(Copy, Clone, Default)]
  98pub struct RemoveOptions {
  99    pub recursive: bool,
 100    pub ignore_if_not_exists: bool,
 101}
 102
 103#[derive(Copy, Clone, Debug)]
 104pub struct Metadata {
 105    pub inode: u64,
 106    pub mtime: SystemTime,
 107    pub is_symlink: bool,
 108    pub is_dir: bool,
 109}
 110
 111pub struct RealFs;
 112
 113#[async_trait::async_trait]
 114impl Fs for RealFs {
 115    async fn create_dir(&self, path: &Path) -> Result<()> {
 116        Ok(smol::fs::create_dir_all(path).await?)
 117    }
 118
 119    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()> {
 120        #[cfg(target_family = "unix")]
 121        smol::fs::unix::symlink(target, path).await?;
 122
 123        #[cfg(target_family = "windows")]
 124        Err(anyhow!("not supported yet on windows"))?;
 125
 126        Ok(())
 127    }
 128
 129    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
 130        let mut open_options = smol::fs::OpenOptions::new();
 131        open_options.write(true).create(true);
 132        if options.overwrite {
 133            open_options.truncate(true);
 134        } else if !options.ignore_if_exists {
 135            open_options.create_new(true);
 136        }
 137        open_options.open(path).await?;
 138        Ok(())
 139    }
 140
 141    async fn create_file_with(
 142        &self,
 143        path: &Path,
 144        content: Pin<&mut (dyn AsyncRead + Send)>,
 145    ) -> Result<()> {
 146        let mut file = smol::fs::File::create(&path).await?;
 147        futures::io::copy(content, &mut file).await?;
 148        Ok(())
 149    }
 150
 151    async fn extract_tar_file(
 152        &self,
 153        path: &Path,
 154        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
 155    ) -> Result<()> {
 156        content.unpack(path).await?;
 157        Ok(())
 158    }
 159
 160    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()> {
 161        if !options.overwrite && smol::fs::metadata(target).await.is_ok() {
 162            if options.ignore_if_exists {
 163                return Ok(());
 164            } else {
 165                return Err(anyhow!("{target:?} already exists"));
 166            }
 167        }
 168
 169        smol::fs::copy(source, target).await?;
 170        Ok(())
 171    }
 172
 173    async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()> {
 174        if !options.overwrite && smol::fs::metadata(target).await.is_ok() {
 175            if options.ignore_if_exists {
 176                return Ok(());
 177            } else {
 178                return Err(anyhow!("{target:?} already exists"));
 179            }
 180        }
 181
 182        smol::fs::rename(source, target).await?;
 183        Ok(())
 184    }
 185
 186    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
 187        let result = if options.recursive {
 188            smol::fs::remove_dir_all(path).await
 189        } else {
 190            smol::fs::remove_dir(path).await
 191        };
 192        match result {
 193            Ok(()) => Ok(()),
 194            Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
 195                Ok(())
 196            }
 197            Err(err) => Err(err)?,
 198        }
 199    }
 200
 201    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
 202        match smol::fs::remove_file(path).await {
 203            Ok(()) => Ok(()),
 204            Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
 205                Ok(())
 206            }
 207            Err(err) => Err(err)?,
 208        }
 209    }
 210
 211    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>> {
 212        Ok(Box::new(std::fs::File::open(path)?))
 213    }
 214
 215    async fn load(&self, path: &Path) -> Result<String> {
 216        let mut file = smol::fs::File::open(path).await?;
 217        // We use `read_exact` here instead of `read_to_string` as the latter is *very*
 218        // happy to reallocate often, which comes into play when we're loading large files.
 219        let mut storage = vec![0; file.metadata().await?.len() as usize];
 220        file.read_exact(&mut storage).await?;
 221        Ok(String::from_utf8(storage)?)
 222    }
 223
 224    async fn atomic_write(&self, path: PathBuf, data: String) -> Result<()> {
 225        smol::unblock(move || {
 226            let mut tmp_file = if cfg!(target_os = "linux") {
 227                // Use the directory of the destination as temp dir to avoid
 228                // invalid cross-device link error, and XDG_CACHE_DIR for fallback.
 229                // See https://github.com/zed-industries/zed/pull/8437 for more details.
 230                NamedTempFile::new_in(path.parent().unwrap_or(&paths::TEMP_DIR))
 231            } else {
 232                NamedTempFile::new()
 233            }?;
 234            tmp_file.write_all(data.as_bytes())?;
 235            tmp_file.persist(path)?;
 236            Ok::<(), anyhow::Error>(())
 237        })
 238        .await?;
 239
 240        Ok(())
 241    }
 242
 243    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()> {
 244        let buffer_size = text.summary().len.min(10 * 1024);
 245        if let Some(path) = path.parent() {
 246            self.create_dir(path).await?;
 247        }
 248        let file = smol::fs::File::create(path).await?;
 249        let mut writer = smol::io::BufWriter::with_capacity(buffer_size, file);
 250        for chunk in chunks(text, line_ending) {
 251            writer.write_all(chunk.as_bytes()).await?;
 252        }
 253        writer.flush().await?;
 254        Ok(())
 255    }
 256
 257    async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
 258        Ok(smol::fs::canonicalize(path).await?)
 259    }
 260
 261    async fn is_file(&self, path: &Path) -> bool {
 262        smol::fs::metadata(path)
 263            .await
 264            .map_or(false, |metadata| metadata.is_file())
 265    }
 266
 267    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
 268        let symlink_metadata = match smol::fs::symlink_metadata(path).await {
 269            Ok(metadata) => metadata,
 270            Err(err) => {
 271                return match (err.kind(), err.raw_os_error()) {
 272                    (io::ErrorKind::NotFound, _) => Ok(None),
 273                    (io::ErrorKind::Other, Some(libc::ENOTDIR)) => Ok(None),
 274                    _ => Err(anyhow::Error::new(err)),
 275                }
 276            }
 277        };
 278
 279        let is_symlink = symlink_metadata.file_type().is_symlink();
 280        let metadata = if is_symlink {
 281            smol::fs::metadata(path).await?
 282        } else {
 283            symlink_metadata
 284        };
 285
 286        #[cfg(unix)]
 287        let inode = metadata.ino();
 288
 289        #[cfg(windows)]
 290        let inode = file_id(path).await?;
 291
 292        Ok(Some(Metadata {
 293            inode,
 294            mtime: metadata.modified().unwrap(),
 295            is_symlink,
 296            is_dir: metadata.file_type().is_dir(),
 297        }))
 298    }
 299
 300    async fn read_link(&self, path: &Path) -> Result<PathBuf> {
 301        let path = smol::fs::read_link(path).await?;
 302        Ok(path)
 303    }
 304
 305    async fn read_dir(
 306        &self,
 307        path: &Path,
 308    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
 309        let result = smol::fs::read_dir(path).await?.map(|entry| match entry {
 310            Ok(entry) => Ok(entry.path()),
 311            Err(error) => Err(anyhow!("failed to read dir entry {:?}", error)),
 312        });
 313        Ok(Box::pin(result))
 314    }
 315
 316    #[cfg(target_os = "macos")]
 317    async fn watch(
 318        &self,
 319        path: &Path,
 320        latency: Duration,
 321    ) -> Pin<Box<dyn Send + Stream<Item = Vec<PathBuf>>>> {
 322        use fsevent::EventStream;
 323
 324        let (tx, rx) = smol::channel::unbounded();
 325        let (stream, handle) = EventStream::new(&[path], latency);
 326        std::thread::spawn(move || {
 327            stream.run(move |events| {
 328                smol::block_on(tx.send(events.into_iter().map(|event| event.path).collect()))
 329                    .is_ok()
 330            });
 331        });
 332
 333        Box::pin(rx.chain(futures::stream::once(async move {
 334            drop(handle);
 335            vec![]
 336        })))
 337    }
 338
 339    #[cfg(not(target_os = "macos"))]
 340    async fn watch(
 341        &self,
 342        path: &Path,
 343        _latency: Duration,
 344    ) -> Pin<Box<dyn Send + Stream<Item = Vec<PathBuf>>>> {
 345        use notify::{event::EventKind, Watcher};
 346        // todo(linux): This spawns two threads, while the macOS impl
 347        // only spawns one. Can we use a OnceLock or some such to make
 348        // this better
 349
 350        let (tx, rx) = smol::channel::unbounded();
 351
 352        let mut file_watcher = notify::recommended_watcher({
 353            let tx = tx.clone();
 354            move |event: Result<notify::Event, _>| {
 355                if let Some(event) = event.log_err() {
 356                    tx.try_send(event.paths).ok();
 357                }
 358            }
 359        })
 360        .expect("Could not start file watcher");
 361
 362        file_watcher
 363            .watch(path, notify::RecursiveMode::Recursive)
 364            .ok(); // It's ok if this fails, the parent watcher will add it.
 365
 366        let mut parent_watcher = notify::recommended_watcher({
 367            let watched_path = path.to_path_buf();
 368            let tx = tx.clone();
 369            move |event: Result<notify::Event, _>| {
 370                if let Some(event) = event.ok() {
 371                    if event.paths.into_iter().any(|path| *path == watched_path) {
 372                        match event.kind {
 373                            EventKind::Create(_) => {
 374                                file_watcher
 375                                    .watch(watched_path.as_path(), notify::RecursiveMode::Recursive)
 376                                    .log_err();
 377                                let _ = tx.try_send(vec![watched_path.clone()]).ok();
 378                            }
 379                            EventKind::Remove(_) => {
 380                                file_watcher.unwatch(&watched_path).log_err();
 381                                let _ = tx.try_send(vec![watched_path.clone()]).ok();
 382                            }
 383                            _ => {}
 384                        }
 385                    }
 386                }
 387            }
 388        })
 389        .expect("Could not start file watcher");
 390
 391        parent_watcher
 392            .watch(
 393                path.parent()
 394                    .expect("Watching root is probably not what you want"),
 395                notify::RecursiveMode::NonRecursive,
 396            )
 397            .expect("Could not start watcher on parent directory");
 398
 399        Box::pin(rx.chain(futures::stream::once(async move {
 400            drop(parent_watcher);
 401            vec![]
 402        })))
 403    }
 404
 405    fn open_repo(&self, dotgit_path: &Path) -> Option<Arc<Mutex<dyn GitRepository>>> {
 406        LibGitRepository::open(dotgit_path)
 407            .log_err()
 408            .map::<Arc<Mutex<dyn GitRepository>>, _>(|libgit_repository| {
 409                Arc::new(Mutex::new(libgit_repository))
 410            })
 411    }
 412
 413    fn is_fake(&self) -> bool {
 414        false
 415    }
 416
 417    /// Checks whether the file system is case sensitive by attempting to create two files
 418    /// that have the same name except for the casing.
 419    ///
 420    /// It creates both files in a temporary directory it removes at the end.
 421    async fn is_case_sensitive(&self) -> Result<bool> {
 422        let temp_dir = TempDir::new()?;
 423        let test_file_1 = temp_dir.path().join("case_sensitivity_test.tmp");
 424        let test_file_2 = temp_dir.path().join("CASE_SENSITIVITY_TEST.TMP");
 425
 426        let create_opts = CreateOptions {
 427            overwrite: false,
 428            ignore_if_exists: false,
 429        };
 430
 431        // Create file1
 432        self.create_file(&test_file_1, create_opts).await?;
 433
 434        // Now check whether it's possible to create file2
 435        let case_sensitive = match self.create_file(&test_file_2, create_opts).await {
 436            Ok(_) => Ok(true),
 437            Err(e) => {
 438                if let Some(io_error) = e.downcast_ref::<io::Error>() {
 439                    if io_error.kind() == io::ErrorKind::AlreadyExists {
 440                        Ok(false)
 441                    } else {
 442                        Err(e)
 443                    }
 444                } else {
 445                    Err(e)
 446                }
 447            }
 448        };
 449
 450        temp_dir.close()?;
 451        case_sensitive
 452    }
 453
 454    #[cfg(any(test, feature = "test-support"))]
 455    fn as_fake(&self) -> &FakeFs {
 456        panic!("called `RealFs::as_fake`")
 457    }
 458}
 459
 460#[cfg(any(test, feature = "test-support"))]
 461pub struct FakeFs {
 462    // Use an unfair lock to ensure tests are deterministic.
 463    state: Mutex<FakeFsState>,
 464    executor: gpui::BackgroundExecutor,
 465}
 466
 467#[cfg(any(test, feature = "test-support"))]
 468struct FakeFsState {
 469    root: Arc<Mutex<FakeFsEntry>>,
 470    next_inode: u64,
 471    next_mtime: SystemTime,
 472    event_txs: Vec<smol::channel::Sender<Vec<PathBuf>>>,
 473    events_paused: bool,
 474    buffered_events: Vec<PathBuf>,
 475    metadata_call_count: usize,
 476    read_dir_call_count: usize,
 477}
 478
 479#[cfg(any(test, feature = "test-support"))]
 480#[derive(Debug)]
 481enum FakeFsEntry {
 482    File {
 483        inode: u64,
 484        mtime: SystemTime,
 485        content: Vec<u8>,
 486    },
 487    Dir {
 488        inode: u64,
 489        mtime: SystemTime,
 490        entries: BTreeMap<String, Arc<Mutex<FakeFsEntry>>>,
 491        git_repo_state: Option<Arc<Mutex<repository::FakeGitRepositoryState>>>,
 492    },
 493    Symlink {
 494        target: PathBuf,
 495    },
 496}
 497
 498#[cfg(any(test, feature = "test-support"))]
 499impl FakeFsState {
 500    fn read_path(&self, target: &Path) -> Result<Arc<Mutex<FakeFsEntry>>> {
 501        Ok(self
 502            .try_read_path(target, true)
 503            .ok_or_else(|| anyhow!("path does not exist: {}", target.display()))?
 504            .0)
 505    }
 506
 507    fn try_read_path(
 508        &self,
 509        target: &Path,
 510        follow_symlink: bool,
 511    ) -> Option<(Arc<Mutex<FakeFsEntry>>, PathBuf)> {
 512        let mut path = target.to_path_buf();
 513        let mut canonical_path = PathBuf::new();
 514        let mut entry_stack = Vec::new();
 515        'outer: loop {
 516            let mut path_components = path.components().peekable();
 517            while let Some(component) = path_components.next() {
 518                match component {
 519                    Component::Prefix(_) => panic!("prefix paths aren't supported"),
 520                    Component::RootDir => {
 521                        entry_stack.clear();
 522                        entry_stack.push(self.root.clone());
 523                        canonical_path.clear();
 524                        canonical_path.push("/");
 525                    }
 526                    Component::CurDir => {}
 527                    Component::ParentDir => {
 528                        entry_stack.pop()?;
 529                        canonical_path.pop();
 530                    }
 531                    Component::Normal(name) => {
 532                        let current_entry = entry_stack.last().cloned()?;
 533                        let current_entry = current_entry.lock();
 534                        if let FakeFsEntry::Dir { entries, .. } = &*current_entry {
 535                            let entry = entries.get(name.to_str().unwrap()).cloned()?;
 536                            if path_components.peek().is_some() || follow_symlink {
 537                                let entry = entry.lock();
 538                                if let FakeFsEntry::Symlink { target, .. } = &*entry {
 539                                    let mut target = target.clone();
 540                                    target.extend(path_components);
 541                                    path = target;
 542                                    continue 'outer;
 543                                }
 544                            }
 545                            entry_stack.push(entry.clone());
 546                            canonical_path.push(name);
 547                        } else {
 548                            return None;
 549                        }
 550                    }
 551                }
 552            }
 553            break;
 554        }
 555        Some((entry_stack.pop()?, canonical_path))
 556    }
 557
 558    fn write_path<Fn, T>(&self, path: &Path, callback: Fn) -> Result<T>
 559    where
 560        Fn: FnOnce(btree_map::Entry<String, Arc<Mutex<FakeFsEntry>>>) -> Result<T>,
 561    {
 562        let path = normalize_path(path);
 563        let filename = path
 564            .file_name()
 565            .ok_or_else(|| anyhow!("cannot overwrite the root"))?;
 566        let parent_path = path.parent().unwrap();
 567
 568        let parent = self.read_path(parent_path)?;
 569        let mut parent = parent.lock();
 570        let new_entry = parent
 571            .dir_entries(parent_path)?
 572            .entry(filename.to_str().unwrap().into());
 573        callback(new_entry)
 574    }
 575
 576    fn emit_event<I, T>(&mut self, paths: I)
 577    where
 578        I: IntoIterator<Item = T>,
 579        T: Into<PathBuf>,
 580    {
 581        self.buffered_events
 582            .extend(paths.into_iter().map(Into::into));
 583
 584        if !self.events_paused {
 585            self.flush_events(self.buffered_events.len());
 586        }
 587    }
 588
 589    fn flush_events(&mut self, mut count: usize) {
 590        count = count.min(self.buffered_events.len());
 591        let events = self.buffered_events.drain(0..count).collect::<Vec<_>>();
 592        self.event_txs.retain(|tx| {
 593            let _ = tx.try_send(events.clone());
 594            !tx.is_closed()
 595        });
 596    }
 597}
 598
 599#[cfg(any(test, feature = "test-support"))]
 600lazy_static::lazy_static! {
 601    pub static ref FS_DOT_GIT: &'static OsStr = OsStr::new(".git");
 602}
 603
 604#[cfg(any(test, feature = "test-support"))]
 605impl FakeFs {
 606    pub fn new(executor: gpui::BackgroundExecutor) -> Arc<Self> {
 607        Arc::new(Self {
 608            executor,
 609            state: Mutex::new(FakeFsState {
 610                root: Arc::new(Mutex::new(FakeFsEntry::Dir {
 611                    inode: 0,
 612                    mtime: SystemTime::UNIX_EPOCH,
 613                    entries: Default::default(),
 614                    git_repo_state: None,
 615                })),
 616                next_mtime: SystemTime::UNIX_EPOCH,
 617                next_inode: 1,
 618                event_txs: Default::default(),
 619                buffered_events: Vec::new(),
 620                events_paused: false,
 621                read_dir_call_count: 0,
 622                metadata_call_count: 0,
 623            }),
 624        })
 625    }
 626
 627    pub async fn insert_file(&self, path: impl AsRef<Path>, content: Vec<u8>) {
 628        self.write_file_internal(path, content).unwrap()
 629    }
 630
 631    pub async fn insert_symlink(&self, path: impl AsRef<Path>, target: PathBuf) {
 632        let mut state = self.state.lock();
 633        let path = path.as_ref();
 634        let file = Arc::new(Mutex::new(FakeFsEntry::Symlink { target }));
 635        state
 636            .write_path(path.as_ref(), move |e| match e {
 637                btree_map::Entry::Vacant(e) => {
 638                    e.insert(file);
 639                    Ok(())
 640                }
 641                btree_map::Entry::Occupied(mut e) => {
 642                    *e.get_mut() = file;
 643                    Ok(())
 644                }
 645            })
 646            .unwrap();
 647        state.emit_event([path]);
 648    }
 649
 650    fn write_file_internal(&self, path: impl AsRef<Path>, content: Vec<u8>) -> Result<()> {
 651        let mut state = self.state.lock();
 652        let path = path.as_ref();
 653        let inode = state.next_inode;
 654        let mtime = state.next_mtime;
 655        state.next_inode += 1;
 656        state.next_mtime += Duration::from_nanos(1);
 657        let file = Arc::new(Mutex::new(FakeFsEntry::File {
 658            inode,
 659            mtime,
 660            content,
 661        }));
 662        state.write_path(path, move |entry| {
 663            match entry {
 664                btree_map::Entry::Vacant(e) => {
 665                    e.insert(file);
 666                }
 667                btree_map::Entry::Occupied(mut e) => {
 668                    *e.get_mut() = file;
 669                }
 670            }
 671            Ok(())
 672        })?;
 673        state.emit_event([path]);
 674        Ok(())
 675    }
 676
 677    async fn load_internal(&self, path: impl AsRef<Path>) -> Result<Vec<u8>> {
 678        let path = path.as_ref();
 679        let path = normalize_path(path);
 680        self.simulate_random_delay().await;
 681        let state = self.state.lock();
 682        let entry = state.read_path(&path)?;
 683        let entry = entry.lock();
 684        entry.file_content(&path).cloned()
 685    }
 686
 687    pub fn pause_events(&self) {
 688        self.state.lock().events_paused = true;
 689    }
 690
 691    pub fn buffered_event_count(&self) -> usize {
 692        self.state.lock().buffered_events.len()
 693    }
 694
 695    pub fn flush_events(&self, count: usize) {
 696        self.state.lock().flush_events(count);
 697    }
 698
 699    #[must_use]
 700    pub fn insert_tree<'a>(
 701        &'a self,
 702        path: impl 'a + AsRef<Path> + Send,
 703        tree: serde_json::Value,
 704    ) -> futures::future::BoxFuture<'a, ()> {
 705        use futures::FutureExt as _;
 706        use serde_json::Value::*;
 707
 708        async move {
 709            let path = path.as_ref();
 710
 711            match tree {
 712                Object(map) => {
 713                    self.create_dir(path).await.unwrap();
 714                    for (name, contents) in map {
 715                        let mut path = PathBuf::from(path);
 716                        path.push(name);
 717                        self.insert_tree(&path, contents).await;
 718                    }
 719                }
 720                Null => {
 721                    self.create_dir(path).await.unwrap();
 722                }
 723                String(contents) => {
 724                    self.insert_file(&path, contents.into_bytes()).await;
 725                }
 726                _ => {
 727                    panic!("JSON object must contain only objects, strings, or null");
 728                }
 729            }
 730        }
 731        .boxed()
 732    }
 733
 734    pub fn insert_tree_from_real_fs<'a>(
 735        &'a self,
 736        path: impl 'a + AsRef<Path> + Send,
 737        src_path: impl 'a + AsRef<Path> + Send,
 738    ) -> futures::future::BoxFuture<'a, ()> {
 739        use futures::FutureExt as _;
 740
 741        async move {
 742            let path = path.as_ref();
 743            if std::fs::metadata(&src_path).unwrap().is_file() {
 744                let contents = std::fs::read(src_path).unwrap();
 745                self.insert_file(path, contents).await;
 746            } else {
 747                self.create_dir(path).await.unwrap();
 748                for entry in std::fs::read_dir(&src_path).unwrap() {
 749                    let entry = entry.unwrap();
 750                    self.insert_tree_from_real_fs(&path.join(entry.file_name()), &entry.path())
 751                        .await;
 752                }
 753            }
 754        }
 755        .boxed()
 756    }
 757
 758    pub fn with_git_state<F>(&self, dot_git: &Path, emit_git_event: bool, f: F)
 759    where
 760        F: FnOnce(&mut FakeGitRepositoryState),
 761    {
 762        let mut state = self.state.lock();
 763        let entry = state.read_path(dot_git).unwrap();
 764        let mut entry = entry.lock();
 765
 766        if let FakeFsEntry::Dir { git_repo_state, .. } = &mut *entry {
 767            let repo_state = git_repo_state.get_or_insert_with(Default::default);
 768            let mut repo_state = repo_state.lock();
 769
 770            f(&mut repo_state);
 771
 772            if emit_git_event {
 773                state.emit_event([dot_git]);
 774            }
 775        } else {
 776            panic!("not a directory");
 777        }
 778    }
 779
 780    pub fn set_branch_name(&self, dot_git: &Path, branch: Option<impl Into<String>>) {
 781        self.with_git_state(dot_git, true, |state| {
 782            state.branch_name = branch.map(Into::into)
 783        })
 784    }
 785
 786    pub fn set_index_for_repo(&self, dot_git: &Path, head_state: &[(&Path, String)]) {
 787        self.with_git_state(dot_git, true, |state| {
 788            state.index_contents.clear();
 789            state.index_contents.extend(
 790                head_state
 791                    .iter()
 792                    .map(|(path, content)| (path.to_path_buf(), content.clone())),
 793            );
 794        });
 795    }
 796
 797    pub fn set_status_for_repo_via_working_copy_change(
 798        &self,
 799        dot_git: &Path,
 800        statuses: &[(&Path, GitFileStatus)],
 801    ) {
 802        self.with_git_state(dot_git, false, |state| {
 803            state.worktree_statuses.clear();
 804            state.worktree_statuses.extend(
 805                statuses
 806                    .iter()
 807                    .map(|(path, content)| ((**path).into(), *content)),
 808            );
 809        });
 810        self.state.lock().emit_event(
 811            statuses
 812                .iter()
 813                .map(|(path, _)| dot_git.parent().unwrap().join(path)),
 814        );
 815    }
 816
 817    pub fn set_status_for_repo_via_git_operation(
 818        &self,
 819        dot_git: &Path,
 820        statuses: &[(&Path, GitFileStatus)],
 821    ) {
 822        self.with_git_state(dot_git, true, |state| {
 823            state.worktree_statuses.clear();
 824            state.worktree_statuses.extend(
 825                statuses
 826                    .iter()
 827                    .map(|(path, content)| ((**path).into(), *content)),
 828            );
 829        });
 830    }
 831
 832    pub fn paths(&self, include_dot_git: bool) -> Vec<PathBuf> {
 833        let mut result = Vec::new();
 834        let mut queue = collections::VecDeque::new();
 835        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 836        while let Some((path, entry)) = queue.pop_front() {
 837            if let FakeFsEntry::Dir { entries, .. } = &*entry.lock() {
 838                for (name, entry) in entries {
 839                    queue.push_back((path.join(name), entry.clone()));
 840                }
 841            }
 842            if include_dot_git
 843                || !path
 844                    .components()
 845                    .any(|component| component.as_os_str() == *FS_DOT_GIT)
 846            {
 847                result.push(path);
 848            }
 849        }
 850        result
 851    }
 852
 853    pub fn directories(&self, include_dot_git: bool) -> Vec<PathBuf> {
 854        let mut result = Vec::new();
 855        let mut queue = collections::VecDeque::new();
 856        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 857        while let Some((path, entry)) = queue.pop_front() {
 858            if let FakeFsEntry::Dir { entries, .. } = &*entry.lock() {
 859                for (name, entry) in entries {
 860                    queue.push_back((path.join(name), entry.clone()));
 861                }
 862                if include_dot_git
 863                    || !path
 864                        .components()
 865                        .any(|component| component.as_os_str() == *FS_DOT_GIT)
 866                {
 867                    result.push(path);
 868                }
 869            }
 870        }
 871        result
 872    }
 873
 874    pub fn files(&self) -> Vec<PathBuf> {
 875        let mut result = Vec::new();
 876        let mut queue = collections::VecDeque::new();
 877        queue.push_back((PathBuf::from("/"), self.state.lock().root.clone()));
 878        while let Some((path, entry)) = queue.pop_front() {
 879            let e = entry.lock();
 880            match &*e {
 881                FakeFsEntry::File { .. } => result.push(path),
 882                FakeFsEntry::Dir { entries, .. } => {
 883                    for (name, entry) in entries {
 884                        queue.push_back((path.join(name), entry.clone()));
 885                    }
 886                }
 887                FakeFsEntry::Symlink { .. } => {}
 888            }
 889        }
 890        result
 891    }
 892
 893    /// How many `read_dir` calls have been issued.
 894    pub fn read_dir_call_count(&self) -> usize {
 895        self.state.lock().read_dir_call_count
 896    }
 897
 898    /// How many `metadata` calls have been issued.
 899    pub fn metadata_call_count(&self) -> usize {
 900        self.state.lock().metadata_call_count
 901    }
 902
 903    fn simulate_random_delay(&self) -> impl futures::Future<Output = ()> {
 904        self.executor.simulate_random_delay()
 905    }
 906}
 907
 908#[cfg(any(test, feature = "test-support"))]
 909impl FakeFsEntry {
 910    fn is_file(&self) -> bool {
 911        matches!(self, Self::File { .. })
 912    }
 913
 914    fn is_symlink(&self) -> bool {
 915        matches!(self, Self::Symlink { .. })
 916    }
 917
 918    fn file_content(&self, path: &Path) -> Result<&Vec<u8>> {
 919        if let Self::File { content, .. } = self {
 920            Ok(content)
 921        } else {
 922            Err(anyhow!("not a file: {}", path.display()))
 923        }
 924    }
 925
 926    fn set_file_content(&mut self, path: &Path, new_content: Vec<u8>) -> Result<()> {
 927        if let Self::File { content, mtime, .. } = self {
 928            *mtime = SystemTime::now();
 929            *content = new_content;
 930            Ok(())
 931        } else {
 932            Err(anyhow!("not a file: {}", path.display()))
 933        }
 934    }
 935
 936    fn dir_entries(
 937        &mut self,
 938        path: &Path,
 939    ) -> Result<&mut BTreeMap<String, Arc<Mutex<FakeFsEntry>>>> {
 940        if let Self::Dir { entries, .. } = self {
 941            Ok(entries)
 942        } else {
 943            Err(anyhow!("not a directory: {}", path.display()))
 944        }
 945    }
 946}
 947
 948#[cfg(any(test, feature = "test-support"))]
 949#[async_trait::async_trait]
 950impl Fs for FakeFs {
 951    async fn create_dir(&self, path: &Path) -> Result<()> {
 952        self.simulate_random_delay().await;
 953
 954        let mut created_dirs = Vec::new();
 955        let mut cur_path = PathBuf::new();
 956        for component in path.components() {
 957            let mut state = self.state.lock();
 958            cur_path.push(component);
 959            if cur_path == Path::new("/") {
 960                continue;
 961            }
 962
 963            let inode = state.next_inode;
 964            let mtime = state.next_mtime;
 965            state.next_mtime += Duration::from_nanos(1);
 966            state.next_inode += 1;
 967            state.write_path(&cur_path, |entry| {
 968                entry.or_insert_with(|| {
 969                    created_dirs.push(cur_path.clone());
 970                    Arc::new(Mutex::new(FakeFsEntry::Dir {
 971                        inode,
 972                        mtime,
 973                        entries: Default::default(),
 974                        git_repo_state: None,
 975                    }))
 976                });
 977                Ok(())
 978            })?
 979        }
 980
 981        self.state.lock().emit_event(&created_dirs);
 982        Ok(())
 983    }
 984
 985    async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
 986        self.simulate_random_delay().await;
 987        let mut state = self.state.lock();
 988        let inode = state.next_inode;
 989        let mtime = state.next_mtime;
 990        state.next_mtime += Duration::from_nanos(1);
 991        state.next_inode += 1;
 992        let file = Arc::new(Mutex::new(FakeFsEntry::File {
 993            inode,
 994            mtime,
 995            content: Vec::new(),
 996        }));
 997        state.write_path(path, |entry| {
 998            match entry {
 999                btree_map::Entry::Occupied(mut e) => {
1000                    if options.overwrite {
1001                        *e.get_mut() = file;
1002                    } else if !options.ignore_if_exists {
1003                        return Err(anyhow!("path already exists: {}", path.display()));
1004                    }
1005                }
1006                btree_map::Entry::Vacant(e) => {
1007                    e.insert(file);
1008                }
1009            }
1010            Ok(())
1011        })?;
1012        state.emit_event([path]);
1013        Ok(())
1014    }
1015
1016    async fn create_symlink(&self, path: &Path, target: PathBuf) -> Result<()> {
1017        let mut state = self.state.lock();
1018        let file = Arc::new(Mutex::new(FakeFsEntry::Symlink { target }));
1019        state
1020            .write_path(path.as_ref(), move |e| match e {
1021                btree_map::Entry::Vacant(e) => {
1022                    e.insert(file);
1023                    Ok(())
1024                }
1025                btree_map::Entry::Occupied(mut e) => {
1026                    *e.get_mut() = file;
1027                    Ok(())
1028                }
1029            })
1030            .unwrap();
1031        state.emit_event(&[path]);
1032        Ok(())
1033    }
1034
1035    async fn create_file_with(
1036        &self,
1037        path: &Path,
1038        mut content: Pin<&mut (dyn AsyncRead + Send)>,
1039    ) -> Result<()> {
1040        let mut bytes = Vec::new();
1041        content.read_to_end(&mut bytes).await?;
1042        self.write_file_internal(path, bytes)?;
1043        Ok(())
1044    }
1045
1046    async fn extract_tar_file(
1047        &self,
1048        path: &Path,
1049        content: Archive<Pin<&mut (dyn AsyncRead + Send)>>,
1050    ) -> Result<()> {
1051        let mut entries = content.entries()?;
1052        while let Some(entry) = entries.next().await {
1053            let mut entry = entry?;
1054            if entry.header().entry_type().is_file() {
1055                let path = path.join(entry.path()?.as_ref());
1056                let mut bytes = Vec::new();
1057                entry.read_to_end(&mut bytes).await?;
1058                self.create_dir(path.parent().unwrap()).await?;
1059                self.write_file_internal(&path, bytes)?;
1060            }
1061        }
1062        Ok(())
1063    }
1064
1065    async fn rename(&self, old_path: &Path, new_path: &Path, options: RenameOptions) -> Result<()> {
1066        self.simulate_random_delay().await;
1067
1068        let old_path = normalize_path(old_path);
1069        let new_path = normalize_path(new_path);
1070
1071        let mut state = self.state.lock();
1072        let moved_entry = state.write_path(&old_path, |e| {
1073            if let btree_map::Entry::Occupied(e) = e {
1074                Ok(e.get().clone())
1075            } else {
1076                Err(anyhow!("path does not exist: {}", &old_path.display()))
1077            }
1078        })?;
1079
1080        state.write_path(&new_path, |e| {
1081            match e {
1082                btree_map::Entry::Occupied(mut e) => {
1083                    if options.overwrite {
1084                        *e.get_mut() = moved_entry;
1085                    } else if !options.ignore_if_exists {
1086                        return Err(anyhow!("path already exists: {}", new_path.display()));
1087                    }
1088                }
1089                btree_map::Entry::Vacant(e) => {
1090                    e.insert(moved_entry);
1091                }
1092            }
1093            Ok(())
1094        })?;
1095
1096        state
1097            .write_path(&old_path, |e| {
1098                if let btree_map::Entry::Occupied(e) = e {
1099                    Ok(e.remove())
1100                } else {
1101                    unreachable!()
1102                }
1103            })
1104            .unwrap();
1105
1106        state.emit_event(&[old_path, new_path]);
1107        Ok(())
1108    }
1109
1110    async fn copy_file(&self, source: &Path, target: &Path, options: CopyOptions) -> Result<()> {
1111        self.simulate_random_delay().await;
1112
1113        let source = normalize_path(source);
1114        let target = normalize_path(target);
1115        let mut state = self.state.lock();
1116        let mtime = state.next_mtime;
1117        let inode = util::post_inc(&mut state.next_inode);
1118        state.next_mtime += Duration::from_nanos(1);
1119        let source_entry = state.read_path(&source)?;
1120        let content = source_entry.lock().file_content(&source)?.clone();
1121        let entry = state.write_path(&target, |e| match e {
1122            btree_map::Entry::Occupied(e) => {
1123                if options.overwrite {
1124                    Ok(Some(e.get().clone()))
1125                } else if !options.ignore_if_exists {
1126                    return Err(anyhow!("{target:?} already exists"));
1127                } else {
1128                    Ok(None)
1129                }
1130            }
1131            btree_map::Entry::Vacant(e) => Ok(Some(
1132                e.insert(Arc::new(Mutex::new(FakeFsEntry::File {
1133                    inode,
1134                    mtime,
1135                    content: Vec::new(),
1136                })))
1137                .clone(),
1138            )),
1139        })?;
1140        if let Some(entry) = entry {
1141            entry.lock().set_file_content(&target, content)?;
1142        }
1143        state.emit_event(&[target]);
1144        Ok(())
1145    }
1146
1147    async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
1148        self.simulate_random_delay().await;
1149
1150        let path = normalize_path(path);
1151        let parent_path = path
1152            .parent()
1153            .ok_or_else(|| anyhow!("cannot remove the root"))?;
1154        let base_name = path.file_name().unwrap();
1155
1156        let mut state = self.state.lock();
1157        let parent_entry = state.read_path(parent_path)?;
1158        let mut parent_entry = parent_entry.lock();
1159        let entry = parent_entry
1160            .dir_entries(parent_path)?
1161            .entry(base_name.to_str().unwrap().into());
1162
1163        match entry {
1164            btree_map::Entry::Vacant(_) => {
1165                if !options.ignore_if_not_exists {
1166                    return Err(anyhow!("{path:?} does not exist"));
1167                }
1168            }
1169            btree_map::Entry::Occupied(e) => {
1170                {
1171                    let mut entry = e.get().lock();
1172                    let children = entry.dir_entries(&path)?;
1173                    if !options.recursive && !children.is_empty() {
1174                        return Err(anyhow!("{path:?} is not empty"));
1175                    }
1176                }
1177                e.remove();
1178            }
1179        }
1180        state.emit_event(&[path]);
1181        Ok(())
1182    }
1183
1184    async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
1185        self.simulate_random_delay().await;
1186
1187        let path = normalize_path(path);
1188        let parent_path = path
1189            .parent()
1190            .ok_or_else(|| anyhow!("cannot remove the root"))?;
1191        let base_name = path.file_name().unwrap();
1192        let mut state = self.state.lock();
1193        let parent_entry = state.read_path(parent_path)?;
1194        let mut parent_entry = parent_entry.lock();
1195        let entry = parent_entry
1196            .dir_entries(parent_path)?
1197            .entry(base_name.to_str().unwrap().into());
1198        match entry {
1199            btree_map::Entry::Vacant(_) => {
1200                if !options.ignore_if_not_exists {
1201                    return Err(anyhow!("{path:?} does not exist"));
1202                }
1203            }
1204            btree_map::Entry::Occupied(e) => {
1205                e.get().lock().file_content(&path)?;
1206                e.remove();
1207            }
1208        }
1209        state.emit_event(&[path]);
1210        Ok(())
1211    }
1212
1213    async fn open_sync(&self, path: &Path) -> Result<Box<dyn io::Read>> {
1214        let bytes = self.load_internal(path).await?;
1215        Ok(Box::new(io::Cursor::new(bytes)))
1216    }
1217
1218    async fn load(&self, path: &Path) -> Result<String> {
1219        let content = self.load_internal(path).await?;
1220        Ok(String::from_utf8(content.clone())?)
1221    }
1222
1223    async fn atomic_write(&self, path: PathBuf, data: String) -> Result<()> {
1224        self.simulate_random_delay().await;
1225        let path = normalize_path(path.as_path());
1226        self.write_file_internal(path, data.into_bytes())?;
1227        Ok(())
1228    }
1229
1230    async fn save(&self, path: &Path, text: &Rope, line_ending: LineEnding) -> Result<()> {
1231        self.simulate_random_delay().await;
1232        let path = normalize_path(path);
1233        let content = chunks(text, line_ending).collect::<String>();
1234        if let Some(path) = path.parent() {
1235            self.create_dir(path).await?;
1236        }
1237        self.write_file_internal(path, content.into_bytes())?;
1238        Ok(())
1239    }
1240
1241    async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
1242        let path = normalize_path(path);
1243        self.simulate_random_delay().await;
1244        let state = self.state.lock();
1245        if let Some((_, canonical_path)) = state.try_read_path(&path, true) {
1246            Ok(canonical_path)
1247        } else {
1248            Err(anyhow!("path does not exist: {}", path.display()))
1249        }
1250    }
1251
1252    async fn is_file(&self, path: &Path) -> bool {
1253        let path = normalize_path(path);
1254        self.simulate_random_delay().await;
1255        let state = self.state.lock();
1256        if let Some((entry, _)) = state.try_read_path(&path, true) {
1257            entry.lock().is_file()
1258        } else {
1259            false
1260        }
1261    }
1262
1263    async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
1264        self.simulate_random_delay().await;
1265        let path = normalize_path(path);
1266        let mut state = self.state.lock();
1267        state.metadata_call_count += 1;
1268        if let Some((mut entry, _)) = state.try_read_path(&path, false) {
1269            let is_symlink = entry.lock().is_symlink();
1270            if is_symlink {
1271                if let Some(e) = state.try_read_path(&path, true).map(|e| e.0) {
1272                    entry = e;
1273                } else {
1274                    return Ok(None);
1275                }
1276            }
1277
1278            let entry = entry.lock();
1279            Ok(Some(match &*entry {
1280                FakeFsEntry::File { inode, mtime, .. } => Metadata {
1281                    inode: *inode,
1282                    mtime: *mtime,
1283                    is_dir: false,
1284                    is_symlink,
1285                },
1286                FakeFsEntry::Dir { inode, mtime, .. } => Metadata {
1287                    inode: *inode,
1288                    mtime: *mtime,
1289                    is_dir: true,
1290                    is_symlink,
1291                },
1292                FakeFsEntry::Symlink { .. } => unreachable!(),
1293            }))
1294        } else {
1295            Ok(None)
1296        }
1297    }
1298
1299    async fn read_link(&self, path: &Path) -> Result<PathBuf> {
1300        self.simulate_random_delay().await;
1301        let path = normalize_path(path);
1302        let state = self.state.lock();
1303        if let Some((entry, _)) = state.try_read_path(&path, false) {
1304            let entry = entry.lock();
1305            if let FakeFsEntry::Symlink { target } = &*entry {
1306                Ok(target.clone())
1307            } else {
1308                Err(anyhow!("not a symlink: {}", path.display()))
1309            }
1310        } else {
1311            Err(anyhow!("path does not exist: {}", path.display()))
1312        }
1313    }
1314
1315    async fn read_dir(
1316        &self,
1317        path: &Path,
1318    ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
1319        self.simulate_random_delay().await;
1320        let path = normalize_path(path);
1321        let mut state = self.state.lock();
1322        state.read_dir_call_count += 1;
1323        let entry = state.read_path(&path)?;
1324        let mut entry = entry.lock();
1325        let children = entry.dir_entries(&path)?;
1326        let paths = children
1327            .keys()
1328            .map(|file_name| Ok(path.join(file_name)))
1329            .collect::<Vec<_>>();
1330        Ok(Box::pin(futures::stream::iter(paths)))
1331    }
1332
1333    async fn watch(
1334        &self,
1335        path: &Path,
1336        _: Duration,
1337    ) -> Pin<Box<dyn Send + Stream<Item = Vec<PathBuf>>>> {
1338        self.simulate_random_delay().await;
1339        let (tx, rx) = smol::channel::unbounded();
1340        self.state.lock().event_txs.push(tx);
1341        let path = path.to_path_buf();
1342        let executor = self.executor.clone();
1343        Box::pin(futures::StreamExt::filter(rx, move |events| {
1344            let result = events.iter().any(|evt_path| evt_path.starts_with(&path));
1345            let executor = executor.clone();
1346            async move {
1347                executor.simulate_random_delay().await;
1348                result
1349            }
1350        }))
1351    }
1352
1353    fn open_repo(&self, abs_dot_git: &Path) -> Option<Arc<Mutex<dyn GitRepository>>> {
1354        let state = self.state.lock();
1355        let entry = state.read_path(abs_dot_git).unwrap();
1356        let mut entry = entry.lock();
1357        if let FakeFsEntry::Dir { git_repo_state, .. } = &mut *entry {
1358            let state = git_repo_state
1359                .get_or_insert_with(|| Arc::new(Mutex::new(FakeGitRepositoryState::default())))
1360                .clone();
1361            Some(repository::FakeGitRepository::open(state))
1362        } else {
1363            None
1364        }
1365    }
1366
1367    fn is_fake(&self) -> bool {
1368        true
1369    }
1370
1371    async fn is_case_sensitive(&self) -> Result<bool> {
1372        Ok(true)
1373    }
1374
1375    #[cfg(any(test, feature = "test-support"))]
1376    fn as_fake(&self) -> &FakeFs {
1377        self
1378    }
1379}
1380
1381fn chunks(rope: &Rope, line_ending: LineEnding) -> impl Iterator<Item = &str> {
1382    rope.chunks().flat_map(move |chunk| {
1383        let mut newline = false;
1384        chunk.split('\n').flat_map(move |line| {
1385            let ending = if newline {
1386                Some(line_ending.as_str())
1387            } else {
1388                None
1389            };
1390            newline = true;
1391            ending.into_iter().chain([line])
1392        })
1393    })
1394}
1395
1396pub fn normalize_path(path: &Path) -> PathBuf {
1397    let mut components = path.components().peekable();
1398    let mut ret = if let Some(c @ Component::Prefix(..)) = components.peek().cloned() {
1399        components.next();
1400        PathBuf::from(c.as_os_str())
1401    } else {
1402        PathBuf::new()
1403    };
1404
1405    for component in components {
1406        match component {
1407            Component::Prefix(..) => unreachable!(),
1408            Component::RootDir => {
1409                ret.push(component.as_os_str());
1410            }
1411            Component::CurDir => {}
1412            Component::ParentDir => {
1413                ret.pop();
1414            }
1415            Component::Normal(c) => {
1416                ret.push(c);
1417            }
1418        }
1419    }
1420    ret
1421}
1422
1423pub fn copy_recursive<'a>(
1424    fs: &'a dyn Fs,
1425    source: &'a Path,
1426    target: &'a Path,
1427    options: CopyOptions,
1428) -> BoxFuture<'a, Result<()>> {
1429    use futures::future::FutureExt;
1430
1431    async move {
1432        let metadata = fs
1433            .metadata(source)
1434            .await?
1435            .ok_or_else(|| anyhow!("path does not exist: {}", source.display()))?;
1436        if metadata.is_dir {
1437            if !options.overwrite && fs.metadata(target).await.is_ok_and(|m| m.is_some()) {
1438                if options.ignore_if_exists {
1439                    return Ok(());
1440                } else {
1441                    return Err(anyhow!("{target:?} already exists"));
1442                }
1443            }
1444
1445            let _ = fs
1446                .remove_dir(
1447                    target,
1448                    RemoveOptions {
1449                        recursive: true,
1450                        ignore_if_not_exists: true,
1451                    },
1452                )
1453                .await;
1454            fs.create_dir(target).await?;
1455            let mut children = fs.read_dir(source).await?;
1456            while let Some(child_path) = children.next().await {
1457                if let Ok(child_path) = child_path {
1458                    if let Some(file_name) = child_path.file_name() {
1459                        let child_target_path = target.join(file_name);
1460                        copy_recursive(fs, &child_path, &child_target_path, options).await?;
1461                    }
1462                }
1463            }
1464
1465            Ok(())
1466        } else {
1467            fs.copy_file(source, target, options).await
1468        }
1469    }
1470    .boxed()
1471}
1472
1473// todo(windows)
1474// can we get file id not open the file twice?
1475// https://github.com/rust-lang/rust/issues/63010
1476#[cfg(target_os = "windows")]
1477async fn file_id(path: impl AsRef<Path>) -> Result<u64> {
1478    use std::os::windows::io::AsRawHandle;
1479
1480    use smol::fs::windows::OpenOptionsExt;
1481    use windows_sys::Win32::{
1482        Foundation::HANDLE,
1483        Storage::FileSystem::{
1484            GetFileInformationByHandle, BY_HANDLE_FILE_INFORMATION, FILE_FLAG_BACKUP_SEMANTICS,
1485        },
1486    };
1487
1488    let file = smol::fs::OpenOptions::new()
1489        .read(true)
1490        .custom_flags(FILE_FLAG_BACKUP_SEMANTICS)
1491        .open(path)
1492        .await?;
1493
1494    let mut info: BY_HANDLE_FILE_INFORMATION = unsafe { std::mem::zeroed() };
1495    // https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfileinformationbyhandle
1496    // This function supports Windows XP+
1497    smol::unblock(move || {
1498        let ret = unsafe { GetFileInformationByHandle(file.as_raw_handle() as HANDLE, &mut info) };
1499        if ret == 0 {
1500            return Err(anyhow!(format!("{}", std::io::Error::last_os_error())));
1501        };
1502
1503        Ok(((info.nFileIndexHigh as u64) << 32) | (info.nFileIndexLow as u64))
1504    })
1505    .await
1506}
1507
1508#[cfg(test)]
1509mod tests {
1510    use super::*;
1511    use gpui::BackgroundExecutor;
1512    use serde_json::json;
1513
1514    #[gpui::test]
1515    async fn test_fake_fs(executor: BackgroundExecutor) {
1516        let fs = FakeFs::new(executor.clone());
1517        fs.insert_tree(
1518            "/root",
1519            json!({
1520                "dir1": {
1521                    "a": "A",
1522                    "b": "B"
1523                },
1524                "dir2": {
1525                    "c": "C",
1526                    "dir3": {
1527                        "d": "D"
1528                    }
1529                }
1530            }),
1531        )
1532        .await;
1533
1534        assert_eq!(
1535            fs.files(),
1536            vec![
1537                PathBuf::from("/root/dir1/a"),
1538                PathBuf::from("/root/dir1/b"),
1539                PathBuf::from("/root/dir2/c"),
1540                PathBuf::from("/root/dir2/dir3/d"),
1541            ]
1542        );
1543
1544        fs.create_symlink("/root/dir2/link-to-dir3".as_ref(), "./dir3".into())
1545            .await
1546            .unwrap();
1547
1548        assert_eq!(
1549            fs.canonicalize("/root/dir2/link-to-dir3".as_ref())
1550                .await
1551                .unwrap(),
1552            PathBuf::from("/root/dir2/dir3"),
1553        );
1554        assert_eq!(
1555            fs.canonicalize("/root/dir2/link-to-dir3/d".as_ref())
1556                .await
1557                .unwrap(),
1558            PathBuf::from("/root/dir2/dir3/d"),
1559        );
1560        assert_eq!(
1561            fs.load("/root/dir2/link-to-dir3/d".as_ref()).await.unwrap(),
1562            "D",
1563        );
1564    }
1565}