Merge #1780

1780: add option to disable notify r=matklad a=matklad

This should help if notify uses 100% of CPU. Put

```
{
    "rust-analyzer.useClientWatching": true,
}
```

into `.vscode/settings.json` (or appropriate config of your editor) to use editor's file watching capabilites instead of notify

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

13 files changed, 151 insertions, 71 deletions

diff --git a/Cargo.lock b/Cargo.lock
index c6fbe8ed0..f93f11a82 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -958,7 +958,7 @@ dependencies = [
  "ra_hir 0.1.0",
  "ra_ide_api 0.1.0",
  "ra_project_model 0.1.0",
- "ra_vfs 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ra_vfs 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_vfs_glob 0.1.0",
  "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1065,7 +1065,7 @@ dependencies = [
  "ra_project_model 0.1.0",
  "ra_syntax 0.1.0",
  "ra_text_edit 0.1.0",
- "ra_vfs 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ra_vfs 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_vfs_glob 0.1.0",
  "relative-path 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1165,7 +1165,7 @@ dependencies = [
 
 [[package]]
 name = "ra_vfs"
-version = "0.3.0"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "crossbeam-channel 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1183,7 +1183,7 @@ name = "ra_vfs_glob"
 version = "0.1.0"
 dependencies = [
  "globset 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "ra_vfs 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ra_vfs 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1945,7 +1945,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum quick-error 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9274b940887ce9addde99c4eee6b5c44cc494b182b97e73dc8ffdcb3397fd3f0"
 "checksum quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)" = "6ce23b6b870e8f94f81fb0a363d65d86675884b34a09043c81e5562f11c1f8e1"
 "checksum quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "053a8c8bcc71fcce321828dc897a98ab9760bef03a4fc36693c231e5b3216cfe"
-"checksum ra_vfs 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ccc8b709e0b7ceec822513451b610df1b9370b01953a8bc545a041a6b3bfef01"
+"checksum ra_vfs 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fdf6a0926414eb0c00866eb9274894182302f879cd06b5459c1d8ee7f1234aed"
 "checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
 "checksum rand 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d47eab0e83d9693d40f825f86948aa16eff6750ead4bdffc4ab95b8b3a7f052c"
 "checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
diff --git a/crates/ra_batch/Cargo.toml b/crates/ra_batch/Cargo.toml
index 5fc2703ee..62850746f 100644
--- a/crates/ra_batch/Cargo.toml
+++ b/crates/ra_batch/Cargo.toml
@@ -9,7 +9,7 @@ log = "0.4.5"
 rustc-hash = "1.0"
 crossbeam-channel = "0.3.5"
 
-ra_vfs = "0.3.0"
+ra_vfs = "0.4.0"
 ra_vfs_glob = { path = "../ra_vfs_glob" }
 ra_db = { path = "../ra_db" }
 ra_ide_api = { path = "../ra_ide_api" }
diff --git a/crates/ra_batch/src/lib.rs b/crates/ra_batch/src/lib.rs
index 4e5bad044..07a7e0c86 100644
--- a/crates/ra_batch/src/lib.rs
+++ b/crates/ra_batch/src/lib.rs
@@ -6,7 +6,7 @@ use crossbeam_channel::{unbounded, Receiver};
 use ra_db::{CrateGraph, FileId, SourceRootId};
 use ra_ide_api::{AnalysisChange, AnalysisHost, FeatureFlags};
 use ra_project_model::{PackageRoot, ProjectWorkspace};
-use ra_vfs::{RootEntry, Vfs, VfsChange, VfsTask};
+use ra_vfs::{RootEntry, Vfs, VfsChange, VfsTask, Watch};
 use ra_vfs_glob::RustPackageFilterBuilder;
 
 type Result<T> = std::result::Result<T, Box<dyn Error + Send + Sync>>;
@@ -37,6 +37,7 @@ pub fn load_cargo(root: &Path) -> Result<(AnalysisHost, FxHashMap<SourceRootId,
             })
             .collect(),
         sender,
+        Watch(false),
     );
     let crate_graph = ws.to_crate_graph(&mut |path: &Path| {
         let vfs_file = vfs.load(path);
diff --git a/crates/ra_lsp_server/Cargo.toml b/crates/ra_lsp_server/Cargo.toml
index 07cc2dd32..46a0f958c 100644
--- a/crates/ra_lsp_server/Cargo.toml
+++ b/crates/ra_lsp_server/Cargo.toml
@@ -16,7 +16,7 @@ lsp-types = { version = "0.61.0", features = ["proposed"] }
 rustc-hash = "1.0"
 parking_lot = "0.9.0"
 jod-thread = "0.1.0"
-ra_vfs = "0.3.0"
+ra_vfs = "0.4.0"
 ra_syntax = { path = "../ra_syntax" }
 ra_text_edit = { path = "../ra_text_edit" }
 ra_ide_api = { path = "../ra_ide_api" }
diff --git a/crates/ra_lsp_server/src/config.rs b/crates/ra_lsp_server/src/config.rs
index 5c5ae3e18..cf53e7c4c 100644
--- a/crates/ra_lsp_server/src/config.rs
+++ b/crates/ra_lsp_server/src/config.rs
@@ -15,6 +15,8 @@ pub struct ServerConfig {
     pub publish_decorations: bool,
 
     pub exclude_globs: Vec<String>,
+    #[serde(deserialize_with = "nullable_bool_false")]
+    pub use_client_watching: bool,
 
     pub lru_capacity: Option<usize>,
 
@@ -31,6 +33,7 @@ impl Default for ServerConfig {
         ServerConfig {
             publish_decorations: false,
             exclude_globs: Vec::new(),
+            use_client_watching: false,
             lru_capacity: None,
             with_sysroot: true,
             feature_flags: FxHashMap::default(),
diff --git a/crates/ra_lsp_server/src/main_loop.rs b/crates/ra_lsp_server/src/main_loop.rs
index 80f0216e8..25fa51b8a 100644
--- a/crates/ra_lsp_server/src/main_loop.rs
+++ b/crates/ra_lsp_server/src/main_loop.rs
@@ -9,8 +9,9 @@ use lsp_server::{Connection, ErrorCode, Message, Notification, Request, RequestI
 use lsp_types::{ClientCapabilities, NumberOrString};
 use ra_ide_api::{Canceled, FeatureFlags, FileId, LibraryData, SourceRootId};
 use ra_prof::profile;
-use ra_vfs::VfsTask;
+use ra_vfs::{VfsTask, Watch};
 use relative_path::RelativePathBuf;
+use rustc_hash::FxHashSet;
 use serde::{de::DeserializeOwned, Serialize};
 use threadpool::ThreadPool;
 
@@ -55,72 +56,96 @@ pub fn main_loop(
 ) -> Result<()> {
     log::info!("server_config: {:#?}", config);
 
-    // FIXME: support dynamic workspace loading.
-    let workspaces = {
-        let mut loaded_workspaces = Vec::new();
-        for ws_root in &ws_roots {
-            let workspace = ra_project_model::ProjectWorkspace::discover_with_sysroot(
-                ws_root.as_path(),
-                config.with_sysroot,
-            );
-            match workspace {
-                Ok(workspace) => loaded_workspaces.push(workspace),
-                Err(e) => {
-                    log::error!("loading workspace failed: {}", e);
+    let mut loop_state = LoopState::default();
+    let mut world_state = {
+        // FIXME: support dynamic workspace loading.
+        let workspaces = {
+            let mut loaded_workspaces = Vec::new();
+            for ws_root in &ws_roots {
+                let workspace = ra_project_model::ProjectWorkspace::discover_with_sysroot(
+                    ws_root.as_path(),
+                    config.with_sysroot,
+                );
+                match workspace {
+                    Ok(workspace) => loaded_workspaces.push(workspace),
+                    Err(e) => {
+                        log::error!("loading workspace failed: {}", e);
+
+                        show_message(
+                            req::MessageType::Error,
+                            format!("rust-analyzer failed to load workspace: {}", e),
+                            &connection.sender,
+                        );
+                    }
+                }
+            }
+            loaded_workspaces
+        };
 
+        let globs = config
+            .exclude_globs
+            .iter()
+            .map(|glob| ra_vfs_glob::Glob::new(glob))
+            .collect::<std::result::Result<Vec<_>, _>>()?;
+
+        if config.use_client_watching {
+            let registration_options = req::DidChangeWatchedFilesRegistrationOptions {
+                watchers: workspaces
+                    .iter()
+                    .flat_map(|ws| ws.to_roots())
+                    .filter(|root| root.is_member())
+                    .map(|root| format!("{}/**/*.rs", root.path().display()))
+                    .map(|glob_pattern| req::FileSystemWatcher { glob_pattern, kind: None })
+                    .collect(),
+            };
+            let registration = req::Registration {
+                id: "file-watcher".to_string(),
+                method: "workspace/didChangeWatchedFiles".to_string(),
+                register_options: Some(serde_json::to_value(registration_options).unwrap()),
+            };
+            let params = req::RegistrationParams { registrations: vec![registration] };
+            let request =
+                request_new::<req::RegisterCapability>(loop_state.next_request_id(), params);
+            connection.sender.send(request.into()).unwrap();
+        }
+
+        let feature_flags = {
+            let mut ff = FeatureFlags::default();
+            for (flag, value) in config.feature_flags {
+                if let Err(_) = ff.set(flag.as_str(), value) {
+                    log::error!("unknown feature flag: {:?}", flag);
                     show_message(
                         req::MessageType::Error,
-                        format!("rust-analyzer failed to load workspace: {}", e),
+                        format!("unknown feature flag: {:?}", flag),
                         &connection.sender,
                     );
                 }
             }
-        }
-        loaded_workspaces
-    };
-
-    let globs = config
-        .exclude_globs
-        .iter()
-        .map(|glob| ra_vfs_glob::Glob::new(glob))
-        .collect::<std::result::Result<Vec<_>, _>>()?;
-
-    let feature_flags = {
-        let mut ff = FeatureFlags::default();
-        for (flag, value) in config.feature_flags {
-            if let Err(_) = ff.set(flag.as_str(), value) {
-                log::error!("unknown feature flag: {:?}", flag);
-                show_message(
-                    req::MessageType::Error,
-                    format!("unknown feature flag: {:?}", flag),
-                    &connection.sender,
-                );
-            }
-        }
-        ff
+            ff
+        };
+        log::info!("feature_flags: {:#?}", feature_flags);
+
+        WorldState::new(
+            ws_roots,
+            workspaces,
+            config.lru_capacity,
+            &globs,
+            Watch(!config.use_client_watching),
+            Options {
+                publish_decorations: config.publish_decorations,
+                supports_location_link: client_caps
+                    .text_document
+                    .and_then(|it| it.definition)
+                    .and_then(|it| it.link_support)
+                    .unwrap_or(false),
+            },
+            feature_flags,
+        )
     };
-    log::info!("feature_flags: {:#?}", feature_flags);
-
-    let mut world_state = WorldState::new(
-        ws_roots,
-        workspaces,
-        config.lru_capacity,
-        &globs,
-        Options {
-            publish_decorations: config.publish_decorations,
-            supports_location_link: client_caps
-                .text_document
-                .and_then(|it| it.definition)
-                .and_then(|it| it.link_support)
-                .unwrap_or(false),
-        },
-        feature_flags,
-    );
 
     let pool = ThreadPool::new(THREADPOOL_SIZE);
     let (task_sender, task_receiver) = unbounded::<Task>();
     let (libdata_sender, libdata_receiver) = unbounded::<LibraryData>();
-    let mut loop_state = LoopState::default();
 
     log::info!("server initialized, serving requests");
     {
@@ -227,6 +252,8 @@ impl fmt::Debug for Event {
 
 #[derive(Debug, Default)]
 struct LoopState {
+    next_request_id: u64,
+    pending_responses: FxHashSet<RequestId>,
     pending_requests: PendingRequests,
     subscriptions: Subscriptions,
     // We try not to index more than MAX_IN_FLIGHT_LIBS libraries at the same
@@ -236,6 +263,16 @@ struct LoopState {
     workspace_loaded: bool,
 }
 
+impl LoopState {
+    fn next_request_id(&mut self) -> RequestId {
+        self.next_request_id += 1;
+        let res: RequestId = self.next_request_id.into();
+        let inserted = self.pending_responses.insert(res.clone());
+        assert!(inserted);
+        res
+    }
+}
+
 fn loop_turn(
     pool: &ThreadPool,
     task_sender: &Sender<Task>,
@@ -290,7 +327,12 @@ fn loop_turn(
                 )?;
                 state_changed = true;
             }
-            Message::Response(resp) => log::error!("unexpected response: {:?}", resp),
+            Message::Response(resp) => {
+                let removed = loop_state.pending_responses.remove(&resp.id);
+                if !removed {
+                    log::error!("unexpected response: {:?}", resp)
+                }
+            }
         },
     };
 
@@ -479,6 +521,18 @@ fn on_notification(
         }
         Err(not) => not,
     };
+    let not = match notification_cast::<req::DidChangeWatchedFiles>(not) {
+        Ok(params) => {
+            let mut vfs = state.vfs.write();
+            for change in params.changes {
+                let uri = change.uri;
+                let path = uri.to_file_path().map_err(|()| format!("invalid uri: {}", uri))?;
+                vfs.notify_changed(path)
+            }
+            return Ok(());
+        }
+        Err(not) => not,
+    };
     log::error!("unhandled notification: {:?}", not);
     Ok(())
 }
@@ -682,3 +736,11 @@ where
 {
     Notification::new(N::METHOD.to_string(), params)
 }
+
+fn request_new<R>(id: RequestId, params: R::Params) -> Request
+where
+    R: lsp_types::request::Request,
+    R::Params: Serialize,
+{
+    Request::new(id, R::METHOD.to_string(), params)
+}
diff --git a/crates/ra_lsp_server/src/req.rs b/crates/ra_lsp_server/src/req.rs
index 1b23f0c3d..0540f166e 100644
--- a/crates/ra_lsp_server/src/req.rs
+++ b/crates/ra_lsp_server/src/req.rs
@@ -5,10 +5,11 @@ use serde::{Deserialize, Serialize};
 pub use lsp_types::{
     notification::*, request::*, ApplyWorkspaceEditParams, CodeActionParams, CodeLens,
     CodeLensParams, CompletionParams, CompletionResponse, DidChangeConfigurationParams,
-    DocumentOnTypeFormattingParams, DocumentSymbolParams, DocumentSymbolResponse, Hover,
-    InitializeResult, MessageType, PublishDiagnosticsParams, ReferenceParams, ShowMessageParams,
-    SignatureHelp, TextDocumentEdit, TextDocumentPositionParams, TextEdit, WorkspaceEdit,
-    WorkspaceSymbolParams,
+    DidChangeWatchedFilesParams, DidChangeWatchedFilesRegistrationOptions,
+    DocumentOnTypeFormattingParams, DocumentSymbolParams, DocumentSymbolResponse,
+    FileSystemWatcher, Hover, InitializeResult, MessageType, PublishDiagnosticsParams,
+    ReferenceParams, Registration, RegistrationParams, ShowMessageParams, SignatureHelp,
+    TextDocumentEdit, TextDocumentPositionParams, TextEdit, WorkspaceEdit, WorkspaceSymbolParams,
 };
 
 pub enum AnalyzerStatus {}
diff --git a/crates/ra_lsp_server/src/world.rs b/crates/ra_lsp_server/src/world.rs
index e1c5c3343..086ecd587 100644
--- a/crates/ra_lsp_server/src/world.rs
+++ b/crates/ra_lsp_server/src/world.rs
@@ -12,7 +12,7 @@ use ra_ide_api::{
     SourceRootId,
 };
 use ra_project_model::ProjectWorkspace;
-use ra_vfs::{LineEndings, RootEntry, Vfs, VfsChange, VfsFile, VfsRoot, VfsTask};
+use ra_vfs::{LineEndings, RootEntry, Vfs, VfsChange, VfsFile, VfsRoot, VfsTask, Watch};
 use ra_vfs_glob::{Glob, RustPackageFilterBuilder};
 use relative_path::RelativePathBuf;
 
@@ -60,6 +60,7 @@ impl WorldState {
         workspaces: Vec<ProjectWorkspace>,
         lru_capacity: Option<usize>,
         exclude_globs: &[Glob],
+        watch: Watch,
         options: Options,
         feature_flags: FeatureFlags,
     ) -> WorldState {
@@ -85,7 +86,7 @@ impl WorldState {
         }
         let (task_sender, task_receiver) = unbounded();
         let task_sender = Box::new(move |t| task_sender.send(t).unwrap());
-        let (mut vfs, vfs_roots) = Vfs::new(roots, task_sender);
+        let (mut vfs, vfs_roots) = Vfs::new(roots, task_sender, watch);
         let roots_to_scan = vfs_roots.len();
         for r in vfs_roots {
             let vfs_root_path = vfs.root2path(r);
diff --git a/crates/ra_vfs_glob/Cargo.toml b/crates/ra_vfs_glob/Cargo.toml
index 09ba3d3bf..d1073b2be 100644
--- a/crates/ra_vfs_glob/Cargo.toml
+++ b/crates/ra_vfs_glob/Cargo.toml
@@ -5,5 +5,5 @@ version = "0.1.0"
 authors = ["rust-analyzer developers"]
 
 [dependencies]
-ra_vfs = "0.3.0"
+ra_vfs = "0.4.0"
 globset = "0.4.4"
diff --git a/docs/user/README.md b/docs/user/README.md
index 453e8e273..56c2d9eb5 100644
--- a/docs/user/README.md
+++ b/docs/user/README.md
@@ -74,6 +74,8 @@ See https://github.com/microsoft/vscode/issues/72308[microsoft/vscode#72308] for
 * `rust-analyzer.excludeGlobs`: a list of glob-patterns for exclusion (see globset [docs](https://docs.rs/globset) for syntax).
   Note: glob patterns are applied to all Cargo packages and a rooted at a package root.
   This is not very intuitive and a limitation of a current implementation.
+* `rust-analyzer.useClientWatching`: use client provided file watching instead
+  of notify watching.
 * `rust-analyzer.cargo-watch.check-arguments`: cargo-watch check arguments.
   (e.g: `--features="shumway,pdf"` will run as `cargo watch -x "check --features="shumway,pdf""` )
 * `rust-analyzer.trace.server`: enables internal logging
diff --git a/editors/code/package.json b/editors/code/package.json
index e2bc72f32..7a48d6794 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -205,6 +205,11 @@
                     "default": [],
                     "description": "Paths to exclude from analysis"
                 },
+                "rust-analyzer.useClientWatching": {
+                    "type": "boolean",
+                    "default": false,
+                    "description": "client provided file watching instead of notify watching."
+                },
                 "rust-analyzer.cargo-watch.arguments": {
                     "type": "string",
                     "description": "`cargo-watch` arguments. (e.g: `--features=\"shumway,pdf\"` will run as `cargo watch -x \"check --features=\"shumway,pdf\"\"` )",
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index 570ddca46..a4581485c 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -23,6 +23,7 @@ export class Config {
     public lruCapacity: null | number = null;
     public displayInlayHints = true;
     public excludeGlobs = [];
+    public useClientWatching = false;
     public featureFlags = {};
     public cargoWatchOptions: CargoWatchOptions = {
         enableOnStartup: 'ask',
@@ -133,6 +134,9 @@ export class Config {
         if (config.has('excludeGlobs')) {
             this.excludeGlobs = config.get('excludeGlobs') || [];
         }
+        if (config.has('useClientWatching')) {
+            this.useClientWatching = config.get('useClientWatching') || false;
+        }
         if (config.has('featureFlags')) {
             this.featureFlags = config.get('featureFlags') || {};
         }
diff --git a/editors/code/src/server.ts b/editors/code/src/server.ts
index 0d2a99c70..ff50fcd99 100644
--- a/editors/code/src/server.ts
+++ b/editors/code/src/server.ts
@@ -46,6 +46,7 @@ export class Server {
                     Server.config.showWorkspaceLoadedNotification,
                 lruCapacity: Server.config.lruCapacity,
                 excludeGlobs: Server.config.excludeGlobs,
+                useClientWatching: Server.config.useClientWatching,
                 featureFlags: Server.config.featureFlags
             },
             traceOutputChannel