Merge #671

671: Makre VFS slightly less super obscure r=vemoo a=matklad

I've decided to better understand what we do in VFS, and this turns out to be really hard. Jugling threads and channels is one of the most unfortunately arcane bits of rust...

I had some success though by flattenning the structure so that all channel & thread creation routines are on one screen. 

r? @vemoo 

Co-authored-by: Aleksey Kladov <[email protected]>

1 files changed, 0 insertions, 200 deletions

diff --git a/crates/ra_vfs/src/io/watcher.rs b/crates/ra_vfs/src/io/watcher.rs
deleted file mode 100644
index ff6775f59..000000000
--- a/crates/ra_vfs/src/io/watcher.rs
+++ /dev/null
@@ -1,200 +0,0 @@
-use crate::{io, RootFilter, Roots, VfsRoot};
-use crossbeam_channel::Sender;
-use drop_bomb::DropBomb;
-use notify::{DebouncedEvent, RecommendedWatcher, RecursiveMode, Watcher as NotifyWatcher};
-use parking_lot::Mutex;
-use std::{
-    fs,
-    path::{Path, PathBuf},
-    sync::{mpsc, Arc},
-    thread,
-    time::Duration,
-};
-use walkdir::WalkDir;
-
-#[derive(Debug)]
-enum ChangeKind {
-    Create,
-    Write,
-    Remove,
-}
-
-const WATCHER_DELAY: Duration = Duration::from_millis(250);
-
-pub(crate) struct Watcher {
-    thread: thread::JoinHandle<()>,
-    bomb: DropBomb,
-    watcher: Arc<Mutex<Option<RecommendedWatcher>>>,
-}
-
-impl Watcher {
-    pub(crate) fn start(
-        roots: Arc<Roots>,
-        output_sender: Sender<io::TaskResult>,
-    ) -> Result<Watcher, Box<std::error::Error>> {
-        let (input_sender, input_receiver) = mpsc::channel();
-        let watcher = Arc::new(Mutex::new(Some(notify::watcher(
-            input_sender,
-            WATCHER_DELAY,
-        )?)));
-        let sender = output_sender.clone();
-        let watcher_clone = watcher.clone();
-        let thread = thread::spawn(move || {
-            let worker = WatcherWorker {
-                roots,
-                watcher: watcher_clone,
-                sender,
-            };
-            input_receiver
-                .into_iter()
-                // forward relevant events only
-                .try_for_each(|change| worker.handle_debounced_event(change))
-                .unwrap()
-        });
-        Ok(Watcher {
-            thread,
-            watcher,
-            bomb: DropBomb::new(format!("Watcher was not shutdown")),
-        })
-    }
-
-    pub fn watch_root(&mut self, filter: &RootFilter) {
-        for res in WalkDir::new(&filter.root)
-            .into_iter()
-            .filter_entry(filter.entry_filter())
-        {
-            match res {
-                Ok(entry) => {
-                    if entry.file_type().is_dir() {
-                        watch_one(self.watcher.as_ref(), entry.path());
-                    }
-                }
-                Err(e) => log::warn!("watcher error: {}", e),
-            }
-        }
-    }
-
-    pub fn shutdown(mut self) -> thread::Result<()> {
-        self.bomb.defuse();
-        drop(self.watcher.lock().take());
-        let res = self.thread.join();
-        match &res {
-            Ok(()) => log::info!("... Watcher terminated with ok"),
-            Err(_) => log::error!("... Watcher terminated with err"),
-        }
-        res
-    }
-}
-
-struct WatcherWorker {
-    watcher: Arc<Mutex<Option<RecommendedWatcher>>>,
-    roots: Arc<Roots>,
-    sender: Sender<io::TaskResult>,
-}
-
-impl WatcherWorker {
-    fn handle_debounced_event(&self, ev: DebouncedEvent) -> Result<(), Box<std::error::Error>> {
-        match ev {
-            DebouncedEvent::NoticeWrite(_)
-            | DebouncedEvent::NoticeRemove(_)
-            | DebouncedEvent::Chmod(_) => {
-                // ignore
-            }
-            DebouncedEvent::Rescan => {
-                // TODO rescan all roots
-            }
-            DebouncedEvent::Create(path) => {
-                self.handle_change(path, ChangeKind::Create);
-            }
-            DebouncedEvent::Write(path) => {
-                self.handle_change(path, ChangeKind::Write);
-            }
-            DebouncedEvent::Remove(path) => {
-                self.handle_change(path, ChangeKind::Remove);
-            }
-            DebouncedEvent::Rename(src, dst) => {
-                self.handle_change(src, ChangeKind::Remove);
-                self.handle_change(dst, ChangeKind::Create);
-            }
-            DebouncedEvent::Error(err, path) => {
-                // TODO should we reload the file contents?
-                log::warn!("watcher error \"{}\", {:?}", err, path);
-            }
-        }
-        Ok(())
-    }
-
-    fn handle_change(&self, path: PathBuf, kind: ChangeKind) {
-        if let Err(e) = self.try_handle_change(path, kind) {
-            log::warn!("watcher error: {}", e)
-        }
-    }
-
-    fn try_handle_change(
-        &self,
-        path: PathBuf,
-        kind: ChangeKind,
-    ) -> Result<(), Box<std::error::Error>> {
-        let (root, rel_path) = match self.roots.find(&path) {
-            Some(x) => x,
-            None => return Ok(()),
-        };
-        match kind {
-            ChangeKind::Create => {
-                if path.is_dir() {
-                    self.watch_recursive(&path, root);
-                } else {
-                    let text = fs::read_to_string(&path)?;
-                    self.sender.send(io::TaskResult::AddSingleFile {
-                        root,
-                        path: rel_path,
-                        text,
-                    })?
-                }
-            }
-            ChangeKind::Write => {
-                let text = fs::read_to_string(&path)?;
-                self.sender.send(io::TaskResult::ChangeSingleFile {
-                    root,
-                    path: rel_path,
-                    text,
-                })?
-            }
-            ChangeKind::Remove => self.sender.send(io::TaskResult::RemoveSingleFile {
-                root,
-                path: rel_path,
-            })?,
-        }
-        Ok(())
-    }
-
-    fn watch_recursive(&self, dir: &Path, root: VfsRoot) {
-        let filter = &self.roots[root];
-        for res in WalkDir::new(dir)
-            .into_iter()
-            .filter_entry(filter.entry_filter())
-        {
-            match res {
-                Ok(entry) => {
-                    if entry.file_type().is_dir() {
-                        watch_one(self.watcher.as_ref(), entry.path());
-                    } else {
-                        // emit only for files otherwise we will cause watch_recursive to be called again with a dir that we are already watching
-                        // emit as create because we haven't seen it yet
-                        self.handle_change(entry.path().to_path_buf(), ChangeKind::Create);
-                    }
-                }
-                Err(e) => log::warn!("watcher error: {}", e),
-            }
-        }
-    }
-}
-
-fn watch_one(watcher: &Mutex<Option<RecommendedWatcher>>, dir: &Path) {
-    if let Some(watcher) = watcher.lock().as_mut() {
-        match watcher.watch(dir, RecursiveMode::NonRecursive) {
-            Ok(()) => log::debug!("watching \"{}\"", dir.display()),
-            Err(e) => log::warn!("could not watch \"{}\": {}", dir.display(), e),
-        }
-    }
-}