1use anyhow::{anyhow, Result};
2use fsevent::EventStream;
3use futures::{Stream, StreamExt};
4use smol::io::{AsyncReadExt, AsyncWriteExt};
5use std::{
6 io,
7 os::unix::fs::MetadataExt,
8 path::{Path, PathBuf},
9 pin::Pin,
10 time::{Duration, SystemTime},
11};
12use text::Rope;
13
14#[async_trait::async_trait]
15pub trait Fs: Send + Sync {
16 async fn create_dir(&self, path: &Path) -> Result<()>;
17 async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()>;
18 async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()>;
19 async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()>;
20 async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()>;
21 async fn load(&self, path: &Path) -> Result<String>;
22 async fn save(&self, path: &Path, text: &Rope) -> Result<()>;
23 async fn canonicalize(&self, path: &Path) -> Result<PathBuf>;
24 async fn is_file(&self, path: &Path) -> bool;
25 async fn metadata(&self, path: &Path) -> Result<Option<Metadata>>;
26 async fn read_dir(
27 &self,
28 path: &Path,
29 ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>>;
30 async fn watch(
31 &self,
32 path: &Path,
33 latency: Duration,
34 ) -> Pin<Box<dyn Send + Stream<Item = Vec<fsevent::Event>>>>;
35 fn is_fake(&self) -> bool;
36 #[cfg(any(test, feature = "test-support"))]
37 fn as_fake(&self) -> &FakeFs;
38}
39
40#[derive(Copy, Clone, Default)]
41pub struct CreateOptions {
42 pub overwrite: bool,
43 pub ignore_if_exists: bool,
44}
45
46#[derive(Copy, Clone, Default)]
47pub struct RenameOptions {
48 pub overwrite: bool,
49 pub ignore_if_exists: bool,
50}
51
52#[derive(Copy, Clone, Default)]
53pub struct RemoveOptions {
54 pub recursive: bool,
55 pub ignore_if_not_exists: bool,
56}
57
58#[derive(Clone, Debug)]
59pub struct Metadata {
60 pub inode: u64,
61 pub mtime: SystemTime,
62 pub is_symlink: bool,
63 pub is_dir: bool,
64}
65
66pub struct RealFs;
67
68#[async_trait::async_trait]
69impl Fs for RealFs {
70 async fn create_dir(&self, path: &Path) -> Result<()> {
71 Ok(smol::fs::create_dir_all(path).await?)
72 }
73
74 async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
75 let mut open_options = smol::fs::OpenOptions::new();
76 open_options.write(true).create(true);
77 if options.overwrite {
78 open_options.truncate(true);
79 } else if !options.ignore_if_exists {
80 open_options.create_new(true);
81 }
82 open_options.open(path).await?;
83 Ok(())
84 }
85
86 async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()> {
87 if !options.overwrite && smol::fs::metadata(target).await.is_ok() {
88 if options.ignore_if_exists {
89 return Ok(());
90 } else {
91 return Err(anyhow!("{target:?} already exists"));
92 }
93 }
94
95 smol::fs::rename(source, target).await?;
96 Ok(())
97 }
98
99 async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
100 let result = if options.recursive {
101 smol::fs::remove_dir_all(path).await
102 } else {
103 smol::fs::remove_dir(path).await
104 };
105 match result {
106 Ok(()) => Ok(()),
107 Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
108 Ok(())
109 }
110 Err(err) => Err(err)?,
111 }
112 }
113
114 async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
115 match smol::fs::remove_file(path).await {
116 Ok(()) => Ok(()),
117 Err(err) if err.kind() == io::ErrorKind::NotFound && options.ignore_if_not_exists => {
118 Ok(())
119 }
120 Err(err) => Err(err)?,
121 }
122 }
123
124 async fn load(&self, path: &Path) -> Result<String> {
125 let mut file = smol::fs::File::open(path).await?;
126 let mut text = String::new();
127 file.read_to_string(&mut text).await?;
128 Ok(text)
129 }
130
131 async fn save(&self, path: &Path, text: &Rope) -> Result<()> {
132 let buffer_size = text.summary().bytes.min(10 * 1024);
133 let file = smol::fs::File::create(path).await?;
134 let mut writer = smol::io::BufWriter::with_capacity(buffer_size, file);
135 for chunk in text.chunks() {
136 writer.write_all(chunk.as_bytes()).await?;
137 }
138 writer.flush().await?;
139 Ok(())
140 }
141
142 async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
143 Ok(smol::fs::canonicalize(path).await?)
144 }
145
146 async fn is_file(&self, path: &Path) -> bool {
147 smol::fs::metadata(path)
148 .await
149 .map_or(false, |metadata| metadata.is_file())
150 }
151
152 async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
153 let symlink_metadata = match smol::fs::symlink_metadata(path).await {
154 Ok(metadata) => metadata,
155 Err(err) => {
156 return match (err.kind(), err.raw_os_error()) {
157 (io::ErrorKind::NotFound, _) => Ok(None),
158 (io::ErrorKind::Other, Some(libc::ENOTDIR)) => Ok(None),
159 _ => Err(anyhow::Error::new(err)),
160 }
161 }
162 };
163
164 let is_symlink = symlink_metadata.file_type().is_symlink();
165 let metadata = if is_symlink {
166 smol::fs::metadata(path).await?
167 } else {
168 symlink_metadata
169 };
170 Ok(Some(Metadata {
171 inode: metadata.ino(),
172 mtime: metadata.modified().unwrap(),
173 is_symlink,
174 is_dir: metadata.file_type().is_dir(),
175 }))
176 }
177
178 async fn read_dir(
179 &self,
180 path: &Path,
181 ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
182 let result = smol::fs::read_dir(path).await?.map(|entry| match entry {
183 Ok(entry) => Ok(entry.path()),
184 Err(error) => Err(anyhow!("failed to read dir entry {:?}", error)),
185 });
186 Ok(Box::pin(result))
187 }
188
189 async fn watch(
190 &self,
191 path: &Path,
192 latency: Duration,
193 ) -> Pin<Box<dyn Send + Stream<Item = Vec<fsevent::Event>>>> {
194 let (tx, rx) = smol::channel::unbounded();
195 let (stream, handle) = EventStream::new(&[path], latency);
196 std::mem::forget(handle);
197 std::thread::spawn(move || {
198 stream.run(move |events| smol::block_on(tx.send(events)).is_ok());
199 });
200 Box::pin(rx)
201 }
202
203 fn is_fake(&self) -> bool {
204 false
205 }
206
207 #[cfg(any(test, feature = "test-support"))]
208 fn as_fake(&self) -> &FakeFs {
209 panic!("called `RealFs::as_fake`")
210 }
211}
212
213#[cfg(any(test, feature = "test-support"))]
214#[derive(Clone, Debug)]
215struct FakeFsEntry {
216 metadata: Metadata,
217 content: Option<String>,
218}
219
220#[cfg(any(test, feature = "test-support"))]
221struct FakeFsState {
222 entries: std::collections::BTreeMap<PathBuf, FakeFsEntry>,
223 next_inode: u64,
224 events_tx: postage::broadcast::Sender<Vec<fsevent::Event>>,
225}
226
227#[cfg(any(test, feature = "test-support"))]
228impl FakeFsState {
229 fn validate_path(&self, path: &Path) -> Result<()> {
230 if path.is_absolute()
231 && path
232 .parent()
233 .and_then(|path| self.entries.get(path))
234 .map_or(false, |e| e.metadata.is_dir)
235 {
236 Ok(())
237 } else {
238 Err(anyhow!("invalid path {:?}", path))
239 }
240 }
241
242 async fn emit_event<I, T>(&mut self, paths: I)
243 where
244 I: IntoIterator<Item = T>,
245 T: Into<PathBuf>,
246 {
247 use postage::prelude::Sink as _;
248
249 let events = paths
250 .into_iter()
251 .map(|path| fsevent::Event {
252 event_id: 0,
253 flags: fsevent::StreamFlags::empty(),
254 path: path.into(),
255 })
256 .collect();
257
258 let _ = self.events_tx.send(events).await;
259 }
260}
261
262#[cfg(any(test, feature = "test-support"))]
263pub struct FakeFs {
264 // Use an unfair lock to ensure tests are deterministic.
265 state: futures::lock::Mutex<FakeFsState>,
266 executor: std::sync::Arc<gpui::executor::Background>,
267}
268
269#[cfg(any(test, feature = "test-support"))]
270impl FakeFs {
271 pub fn new(executor: std::sync::Arc<gpui::executor::Background>) -> Self {
272 let (events_tx, _) = postage::broadcast::channel(2048);
273 let mut entries = std::collections::BTreeMap::new();
274 entries.insert(
275 Path::new("/").to_path_buf(),
276 FakeFsEntry {
277 metadata: Metadata {
278 inode: 0,
279 mtime: SystemTime::now(),
280 is_dir: true,
281 is_symlink: false,
282 },
283 content: None,
284 },
285 );
286 Self {
287 executor,
288 state: futures::lock::Mutex::new(FakeFsState {
289 entries,
290 next_inode: 1,
291 events_tx,
292 }),
293 }
294 }
295
296 pub async fn insert_dir(&self, path: impl AsRef<Path>) -> Result<()> {
297 let mut state = self.state.lock().await;
298 let path = path.as_ref();
299 state.validate_path(path)?;
300
301 let inode = state.next_inode;
302 state.next_inode += 1;
303 state.entries.insert(
304 path.to_path_buf(),
305 FakeFsEntry {
306 metadata: Metadata {
307 inode,
308 mtime: SystemTime::now(),
309 is_dir: true,
310 is_symlink: false,
311 },
312 content: None,
313 },
314 );
315 state.emit_event(&[path]).await;
316 Ok(())
317 }
318
319 pub async fn insert_file(&self, path: impl AsRef<Path>, content: String) -> Result<()> {
320 let mut state = self.state.lock().await;
321 let path = path.as_ref();
322 state.validate_path(path)?;
323
324 let inode = state.next_inode;
325 state.next_inode += 1;
326 state.entries.insert(
327 path.to_path_buf(),
328 FakeFsEntry {
329 metadata: Metadata {
330 inode,
331 mtime: SystemTime::now(),
332 is_dir: false,
333 is_symlink: false,
334 },
335 content: Some(content),
336 },
337 );
338 state.emit_event(&[path]).await;
339 Ok(())
340 }
341
342 #[must_use]
343 pub fn insert_tree<'a>(
344 &'a self,
345 path: impl 'a + AsRef<Path> + Send,
346 tree: serde_json::Value,
347 ) -> futures::future::BoxFuture<'a, ()> {
348 use futures::FutureExt as _;
349 use serde_json::Value::*;
350
351 async move {
352 let path = path.as_ref();
353
354 match tree {
355 Object(map) => {
356 self.insert_dir(path).await.unwrap();
357 for (name, contents) in map {
358 let mut path = PathBuf::from(path);
359 path.push(name);
360 self.insert_tree(&path, contents).await;
361 }
362 }
363 Null => {
364 self.insert_dir(&path).await.unwrap();
365 }
366 String(contents) => {
367 self.insert_file(&path, contents).await.unwrap();
368 }
369 _ => {
370 panic!("JSON object must contain only objects, strings, or null");
371 }
372 }
373 }
374 .boxed()
375 }
376}
377
378#[cfg(any(test, feature = "test-support"))]
379#[async_trait::async_trait]
380impl Fs for FakeFs {
381 async fn create_dir(&self, path: &Path) -> Result<()> {
382 self.executor.simulate_random_delay().await;
383 let state = &mut *self.state.lock().await;
384 let mut ancestor_path = PathBuf::new();
385 let mut created_dir_paths = Vec::new();
386 for component in path.components() {
387 ancestor_path.push(component);
388 let entry = state
389 .entries
390 .entry(ancestor_path.clone())
391 .or_insert_with(|| {
392 let inode = state.next_inode;
393 state.next_inode += 1;
394 created_dir_paths.push(ancestor_path.clone());
395 FakeFsEntry {
396 metadata: Metadata {
397 inode,
398 mtime: SystemTime::now(),
399 is_dir: true,
400 is_symlink: false,
401 },
402 content: None,
403 }
404 });
405 if !entry.metadata.is_dir {
406 return Err(anyhow!(
407 "cannot create directory because {:?} is a file",
408 ancestor_path
409 ));
410 }
411 }
412 state.emit_event(&created_dir_paths).await;
413
414 Ok(())
415 }
416
417 async fn create_file(&self, path: &Path, options: CreateOptions) -> Result<()> {
418 self.executor.simulate_random_delay().await;
419 let mut state = self.state.lock().await;
420 state.validate_path(path)?;
421 if let Some(entry) = state.entries.get_mut(path) {
422 if entry.metadata.is_dir || entry.metadata.is_symlink {
423 return Err(anyhow!(
424 "cannot create file because {:?} is a dir or a symlink",
425 path
426 ));
427 }
428
429 if options.overwrite {
430 entry.metadata.mtime = SystemTime::now();
431 entry.content = Some(Default::default());
432 } else if !options.ignore_if_exists {
433 return Err(anyhow!(
434 "cannot create file because {:?} already exists",
435 path
436 ));
437 }
438 } else {
439 let inode = state.next_inode;
440 state.next_inode += 1;
441 let entry = FakeFsEntry {
442 metadata: Metadata {
443 inode,
444 mtime: SystemTime::now(),
445 is_dir: false,
446 is_symlink: false,
447 },
448 content: Some(Default::default()),
449 };
450 state.entries.insert(path.to_path_buf(), entry);
451 }
452 state.emit_event(&[path]).await;
453
454 Ok(())
455 }
456
457 async fn rename(&self, source: &Path, target: &Path, options: RenameOptions) -> Result<()> {
458 let mut state = self.state.lock().await;
459 state.validate_path(source)?;
460 state.validate_path(target)?;
461
462 if !options.overwrite && state.entries.contains_key(target) {
463 if options.ignore_if_exists {
464 return Ok(());
465 } else {
466 return Err(anyhow!("{target:?} already exists"));
467 }
468 }
469
470 let mut removed = Vec::new();
471 state.entries.retain(|path, entry| {
472 if let Ok(relative_path) = path.strip_prefix(source) {
473 removed.push((relative_path.to_path_buf(), entry.clone()));
474 false
475 } else {
476 true
477 }
478 });
479
480 for (relative_path, entry) in removed {
481 let new_path = target.join(relative_path);
482 state.entries.insert(new_path, entry);
483 }
484
485 state.emit_event(&[source, target]).await;
486 Ok(())
487 }
488
489 async fn remove_dir(&self, path: &Path, options: RemoveOptions) -> Result<()> {
490 let mut state = self.state.lock().await;
491 state.validate_path(path)?;
492 if let Some(entry) = state.entries.get(path) {
493 if !entry.metadata.is_dir {
494 return Err(anyhow!("cannot remove {path:?} because it is not a dir"));
495 }
496
497 if !options.recursive {
498 let descendants = state
499 .entries
500 .keys()
501 .filter(|path| path.starts_with(path))
502 .count();
503 if descendants > 1 {
504 return Err(anyhow!("{path:?} is not empty"));
505 }
506 }
507
508 state.entries.retain(|path, _| !path.starts_with(path));
509 state.emit_event(&[path]).await;
510 } else if !options.ignore_if_not_exists {
511 return Err(anyhow!("{path:?} does not exist"));
512 }
513
514 Ok(())
515 }
516
517 async fn remove_file(&self, path: &Path, options: RemoveOptions) -> Result<()> {
518 let mut state = self.state.lock().await;
519 state.validate_path(path)?;
520 if let Some(entry) = state.entries.get(path) {
521 if entry.metadata.is_dir {
522 return Err(anyhow!("cannot remove {path:?} because it is not a file"));
523 }
524
525 state.entries.remove(path);
526 state.emit_event(&[path]).await;
527 } else if !options.ignore_if_not_exists {
528 return Err(anyhow!("{path:?} does not exist"));
529 }
530 Ok(())
531 }
532
533 async fn load(&self, path: &Path) -> Result<String> {
534 self.executor.simulate_random_delay().await;
535 let state = self.state.lock().await;
536 let text = state
537 .entries
538 .get(path)
539 .and_then(|e| e.content.as_ref())
540 .ok_or_else(|| anyhow!("file {:?} does not exist", path))?;
541 Ok(text.clone())
542 }
543
544 async fn save(&self, path: &Path, text: &Rope) -> Result<()> {
545 self.executor.simulate_random_delay().await;
546 let mut state = self.state.lock().await;
547 state.validate_path(path)?;
548 if let Some(entry) = state.entries.get_mut(path) {
549 if entry.metadata.is_dir {
550 Err(anyhow!("cannot overwrite a directory with a file"))
551 } else {
552 entry.content = Some(text.chunks().collect());
553 entry.metadata.mtime = SystemTime::now();
554 state.emit_event(&[path]).await;
555 Ok(())
556 }
557 } else {
558 let inode = state.next_inode;
559 state.next_inode += 1;
560 let entry = FakeFsEntry {
561 metadata: Metadata {
562 inode,
563 mtime: SystemTime::now(),
564 is_dir: false,
565 is_symlink: false,
566 },
567 content: Some(text.chunks().collect()),
568 };
569 state.entries.insert(path.to_path_buf(), entry);
570 state.emit_event(&[path]).await;
571 Ok(())
572 }
573 }
574
575 async fn canonicalize(&self, path: &Path) -> Result<PathBuf> {
576 self.executor.simulate_random_delay().await;
577 Ok(path.to_path_buf())
578 }
579
580 async fn is_file(&self, path: &Path) -> bool {
581 self.executor.simulate_random_delay().await;
582 let state = self.state.lock().await;
583 state
584 .entries
585 .get(path)
586 .map_or(false, |entry| !entry.metadata.is_dir)
587 }
588
589 async fn metadata(&self, path: &Path) -> Result<Option<Metadata>> {
590 self.executor.simulate_random_delay().await;
591 let state = self.state.lock().await;
592 Ok(state.entries.get(path).map(|entry| entry.metadata.clone()))
593 }
594
595 async fn read_dir(
596 &self,
597 abs_path: &Path,
598 ) -> Result<Pin<Box<dyn Send + Stream<Item = Result<PathBuf>>>>> {
599 use futures::{future, stream};
600 self.executor.simulate_random_delay().await;
601 let state = self.state.lock().await;
602 let abs_path = abs_path.to_path_buf();
603 Ok(Box::pin(stream::iter(state.entries.clone()).filter_map(
604 move |(child_path, _)| {
605 future::ready(if child_path.parent() == Some(&abs_path) {
606 Some(Ok(child_path))
607 } else {
608 None
609 })
610 },
611 )))
612 }
613
614 async fn watch(
615 &self,
616 path: &Path,
617 _: Duration,
618 ) -> Pin<Box<dyn Send + Stream<Item = Vec<fsevent::Event>>>> {
619 let state = self.state.lock().await;
620 self.executor.simulate_random_delay().await;
621 let rx = state.events_tx.subscribe();
622 let path = path.to_path_buf();
623 Box::pin(futures::StreamExt::filter(rx, move |events| {
624 let result = events.iter().any(|event| event.path.starts_with(&path));
625 async move { result }
626 }))
627 }
628
629 fn is_fake(&self) -> bool {
630 true
631 }
632
633 #[cfg(any(test, feature = "test-support"))]
634 fn as_fake(&self) -> &FakeFs {
635 self
636 }
637}