1use crate::Watcher;
 2use anyhow::{Context as _, Result};
 3use collections::{BTreeMap, Bound};
 4use fsevent::EventStream;
 5use parking_lot::Mutex;
 6use std::{
 7    path::{Path, PathBuf},
 8    sync::Weak,
 9    thread,
10    time::Duration,
11};
12
13pub struct MacWatcher {
14    events_tx: smol::channel::Sender<Vec<fsevent::Event>>,
15    handles: Weak<Mutex<BTreeMap<PathBuf, fsevent::Handle>>>,
16    latency: Duration,
17}
18
19impl MacWatcher {
20    pub fn new(
21        events_tx: smol::channel::Sender<Vec<fsevent::Event>>,
22        handles: Weak<Mutex<BTreeMap<PathBuf, fsevent::Handle>>>,
23        latency: Duration,
24    ) -> Self {
25        Self {
26            events_tx,
27            handles,
28            latency,
29        }
30    }
31}
32
33impl Watcher for MacWatcher {
34    fn add(&self, path: &Path) -> Result<()> {
35        let handles = self
36            .handles
37            .upgrade()
38            .context("unable to watch path, receiver dropped")?;
39        let mut handles = handles.lock();
40
41        // Return early if an ancestor of this path was already being watched.
42        if let Some((watched_path, _)) = handles
43            .range::<Path, _>((Bound::Unbounded, Bound::Included(path)))
44            .next_back()
45            && path.starts_with(watched_path)
46        {
47            return Ok(());
48        }
49
50        let (stream, handle) = EventStream::new(&[path], self.latency);
51        let tx = self.events_tx.clone();
52        thread::Builder::new()
53            .name("MacWatcher".to_owned())
54            .spawn(move || {
55                stream.run(move |events| smol::block_on(tx.send(events)).is_ok());
56            })
57            .unwrap();
58        handles.insert(path.into(), handle);
59
60        Ok(())
61    }
62
63    fn remove(&self, path: &Path) -> anyhow::Result<()> {
64        let handles = self
65            .handles
66            .upgrade()
67            .context("unable to remove path, receiver dropped")?;
68
69        let mut handles = handles.lock();
70        handles.remove(path);
71        Ok(())
72    }
73}