src/tools/rust-analyzer/crates/rust-analyzer/src/main_loop.rs

   1 //! The main loop of `rust-analyzer` responsible for dispatching LSP
   2 //! requests/replies and notifications back to the client.
   3 use std::{
   4     fmt,
   5     ops::Deref,
   6     sync::Arc,
   7     time::{Duration, Instant},
   8 };
   9
  10 use always_assert::always;
  11 use crossbeam_channel::{select, Receiver};
  12 use flycheck::FlycheckHandle;
  13 use ide_db::base_db::{SourceDatabaseExt, VfsPath};
  14 use itertools::Itertools;
  15 use lsp_server::{Connection, Notification, Request};
  16 use lsp_types::notification::Notification as _;
  17 use vfs::{ChangeKind, FileId};
  18
  19 use crate::{
  20     config::Config,
  21     dispatch::{NotificationDispatcher, RequestDispatcher},
  22     from_proto,
  23     global_state::{file_id_to_url, url_to_file_id, GlobalState},
  24     handlers, lsp_ext,
  25     lsp_utils::{apply_document_changes, notification_is, Progress},
  26     mem_docs::DocumentData,
  27     reload::{self, BuildDataProgress, ProjectWorkspaceProgress},
  28     Result,
  29 };
  30
  31 pub fn main_loop(config: Config, connection: Connection) -> Result<()> {
  32     tracing::info!("initial config: {:#?}", config);
  33
  34     // Windows scheduler implements priority boosts: if thread waits for an
  35     // event (like a condvar), and event fires, priority of the thread is
  36     // temporary bumped. This optimization backfires in our case: each time the
  37     // `main_loop` schedules a task to run on a threadpool, the worker threads
  38     // gets a higher priority, and (on a machine with fewer cores) displaces the
  39     // main loop! We work-around this by marking the main loop as a
  40     // higher-priority thread.
  41     //
  42     // https://docs.microsoft.com/en-us/windows/win32/procthread/scheduling-priorities
  43     // https://docs.microsoft.com/en-us/windows/win32/procthread/priority-boosts
  44     // https://github.com/rust-lang/rust-analyzer/issues/2835
  45     #[cfg(windows)]
  46     unsafe {
  47         use winapi::um::processthreadsapi::*;
  48         let thread = GetCurrentThread();
  49         let thread_priority_above_normal = 1;
  50         SetThreadPriority(thread, thread_priority_above_normal);
  51     }
  52
  53     GlobalState::new(connection.sender, config).run(connection.receiver)
  54 }
  55
  56 enum Event {
  57     Lsp(lsp_server::Message),
  58     Task(Task),
  59     Vfs(vfs::loader::Message),
  60     Flycheck(flycheck::Message),
  61 }
  62
  63 #[derive(Debug)]
  64 pub(crate) enum Task {
  65     Response(lsp_server::Response),
  66     Retry(lsp_server::Request),
  67     Diagnostics(Vec<(FileId, Vec<lsp_types::Diagnostic>)>),
  68     PrimeCaches(PrimeCachesProgress),
  69     FetchWorkspace(ProjectWorkspaceProgress),
  70     FetchBuildData(BuildDataProgress),
  71 }
  72
  73 #[derive(Debug)]
  74 pub(crate) enum PrimeCachesProgress {
  75     Begin,
  76     Report(ide::ParallelPrimeCachesProgress),
  77     End { cancelled: bool },
  78 }
  79
  80 impl fmt::Debug for Event {
  81     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  82         let debug_verbose_not = |not: &Notification, f: &mut fmt::Formatter<'_>| {
  83             f.debug_struct("Notification").field("method", &not.method).finish()
  84         };
  85
  86         match self {
  87             Event::Lsp(lsp_server::Message::Notification(not)) => {
  88                 if notification_is::<lsp_types::notification::DidOpenTextDocument>(not)
  89                     || notification_is::<lsp_types::notification::DidChangeTextDocument>(not)
  90                 {
  91                     return debug_verbose_not(not, f);
  92                 }
  93             }
  94             Event::Task(Task::Response(resp)) => {
  95                 return f
  96                     .debug_struct("Response")
  97                     .field("id", &resp.id)
  98                     .field("error", &resp.error)
  99                     .finish();
 100             }
 101             _ => (),
 102         }
 103         match self {
 104             Event::Lsp(it) => fmt::Debug::fmt(it, f),
 105             Event::Task(it) => fmt::Debug::fmt(it, f),
 106             Event::Vfs(it) => fmt::Debug::fmt(it, f),
 107             Event::Flycheck(it) => fmt::Debug::fmt(it, f),
 108         }
 109     }
 110 }
 111
 112 impl GlobalState {
 113     fn run(mut self, inbox: Receiver<lsp_server::Message>) -> Result<()> {
 114         if self.config.linked_projects().is_empty()
 115             && self.config.detached_files().is_empty()
 116             && self.config.notifications().cargo_toml_not_found
 117         {
 118             self.show_and_log_error("rust-analyzer failed to discover workspace".to_string(), None);
 119         };
 120
 121         if self.config.did_save_text_document_dynamic_registration() {
 122             let save_registration_options = lsp_types::TextDocumentSaveRegistrationOptions {
 123                 include_text: Some(false),
 124                 text_document_registration_options: lsp_types::TextDocumentRegistrationOptions {
 125                     document_selector: Some(vec![
 126                         lsp_types::DocumentFilter {
 127                             language: None,
 128                             scheme: None,
 129                             pattern: Some("**/*.rs".into()),
 130                         },
 131                         lsp_types::DocumentFilter {
 132                             language: None,
 133                             scheme: None,
 134                             pattern: Some("**/Cargo.toml".into()),
 135                         },
 136                         lsp_types::DocumentFilter {
 137                             language: None,
 138                             scheme: None,
 139                             pattern: Some("**/Cargo.lock".into()),
 140                         },
 141                     ]),
 142                 },
 143             };
 144
 145             let registration = lsp_types::Registration {
 146                 id: "textDocument/didSave".to_string(),
 147                 method: "textDocument/didSave".to_string(),
 148                 register_options: Some(serde_json::to_value(save_registration_options).unwrap()),
 149             };
 150             self.send_request::<lsp_types::request::RegisterCapability>(
 151                 lsp_types::RegistrationParams { registrations: vec![registration] },
 152                 |_, _| (),
 153             );
 154         }
 155
 156         self.fetch_workspaces_queue.request_op("startup".to_string());
 157         if let Some(cause) = self.fetch_workspaces_queue.should_start_op() {
 158             self.fetch_workspaces(cause);
 159         }
 160
 161         while let Some(event) = self.next_event(&inbox) {
 162             if let Event::Lsp(lsp_server::Message::Notification(not)) = &event {
 163                 if not.method == lsp_types::notification::Exit::METHOD {
 164                     return Ok(());
 165                 }
 166             }
 167             self.handle_event(event)?
 168         }
 169
 170         Err("client exited without proper shutdown sequence".into())
 171     }
 172
 173     fn next_event(&self, inbox: &Receiver<lsp_server::Message>) -> Option<Event> {
 174         select! {
 175             recv(inbox) -> msg =>
 176                 msg.ok().map(Event::Lsp),
 177
 178             recv(self.task_pool.receiver) -> task =>
 179                 Some(Event::Task(task.unwrap())),
 180
 181             recv(self.loader.receiver) -> task =>
 182                 Some(Event::Vfs(task.unwrap())),
 183
 184             recv(self.flycheck_receiver) -> task =>
 185                 Some(Event::Flycheck(task.unwrap())),
 186         }
 187     }
 188
 189     fn handle_event(&mut self, event: Event) -> Result<()> {
 190         let loop_start = Instant::now();
 191         // NOTE: don't count blocking select! call as a loop-turn time
 192         let _p = profile::span("GlobalState::handle_event");
 193
 194         tracing::debug!("{:?} handle_event({:?})", loop_start, event);
 195         let task_queue_len = self.task_pool.handle.len();
 196         if task_queue_len > 0 {
 197             tracing::info!("task queue len: {}", task_queue_len);
 198         }
 199
 200         let was_quiescent = self.is_quiescent();
 201         match event {
 202             Event::Lsp(msg) => match msg {
 203                 lsp_server::Message::Request(req) => self.on_new_request(loop_start, req),
 204                 lsp_server::Message::Notification(not) => {
 205                     self.on_notification(not)?;
 206                 }
 207                 lsp_server::Message::Response(resp) => self.complete_request(resp),
 208             },
 209             Event::Task(task) => {
 210                 let _p = profile::span("GlobalState::handle_event/task");
 211                 let mut prime_caches_progress = Vec::new();
 212
 213                 self.handle_task(&mut prime_caches_progress, task);
 214                 // Coalesce multiple task events into one loop turn
 215                 while let Ok(task) = self.task_pool.receiver.try_recv() {
 216                     self.handle_task(&mut prime_caches_progress, task);
 217                 }
 218
 219                 for progress in prime_caches_progress {
 220                     let (state, message, fraction);
 221                     match progress {
 222                         PrimeCachesProgress::Begin => {
 223                             state = Progress::Begin;
 224                             message = None;
 225                             fraction = 0.0;
 226                         }
 227                         PrimeCachesProgress::Report(report) => {
 228                             state = Progress::Report;
 229
 230                             message = match &report.crates_currently_indexing[..] {
 231                                 [crate_name] => Some(format!(
 232                                     "{}/{} ({})",
 233                                     report.crates_done, report.crates_total, crate_name
 234                                 )),
 235                                 [crate_name, rest @ ..] => Some(format!(
 236                                     "{}/{} ({} + {} more)",
 237                                     report.crates_done,
 238                                     report.crates_total,
 239                                     crate_name,
 240                                     rest.len()
 241                                 )),
 242                                 _ => None,
 243                             };
 244
 245                             fraction = Progress::fraction(report.crates_done, report.crates_total);
 246                         }
 247                         PrimeCachesProgress::End { cancelled } => {
 248                             state = Progress::End;
 249                             message = None;
 250                             fraction = 1.0;
 251
 252                             self.prime_caches_queue.op_completed(());
 253                             if cancelled {
 254                                 self.prime_caches_queue
 255                                     .request_op("restart after cancellation".to_string());
 256                             }
 257                         }
 258                     };
 259
 260                     self.report_progress("Indexing", state, message, Some(fraction), None);
 261                 }
 262             }
 263             Event::Vfs(message) => {
 264                 let _p = profile::span("GlobalState::handle_event/vfs");
 265                 self.handle_vfs_msg(message);
 266                 // Coalesce many VFS event into a single loop turn
 267                 while let Ok(message) = self.loader.receiver.try_recv() {
 268                     self.handle_vfs_msg(message);
 269                 }
 270             }
 271             Event::Flycheck(message) => {
 272                 let _p = profile::span("GlobalState::handle_event/flycheck");
 273                 self.handle_flycheck_msg(message);
 274                 // Coalesce many flycheck updates into a single loop turn
 275                 while let Ok(message) = self.flycheck_receiver.try_recv() {
 276                     self.handle_flycheck_msg(message);
 277                 }
 278             }
 279         }
 280
 281         let state_changed = self.process_changes();
 282         let memdocs_added_or_removed = self.mem_docs.take_changes();
 283
 284         if self.is_quiescent() {
 285             let became_quiescent = !(was_quiescent
 286                 || self.fetch_workspaces_queue.op_requested()
 287                 || self.fetch_build_data_queue.op_requested());
 288
 289             if became_quiescent {
 290                 // Project has loaded properly, kick off initial flycheck
 291                 self.flycheck.iter().for_each(FlycheckHandle::restart);
 292                 if self.config.prefill_caches() {
 293                     self.prime_caches_queue.request_op("became quiescent".to_string());
 294                 }
 295             }
 296
 297             if !was_quiescent || state_changed {
 298                 // Refresh semantic tokens if the client supports it.
 299                 if self.config.semantic_tokens_refresh() {
 300                     self.semantic_tokens_cache.lock().clear();
 301                     self.send_request::<lsp_types::request::SemanticTokensRefresh>((), |_, _| ());
 302                 }
 303
 304                 // Refresh code lens if the client supports it.
 305                 if self.config.code_lens_refresh() {
 306                     self.send_request::<lsp_types::request::CodeLensRefresh>((), |_, _| ());
 307                 }
 308             }
 309
 310             if !was_quiescent || state_changed || memdocs_added_or_removed {
 311                 if self.config.publish_diagnostics() {
 312                     self.update_diagnostics()
 313                 }
 314             }
 315         }
 316
 317         if let Some(diagnostic_changes) = self.diagnostics.take_changes() {
 318             for file_id in diagnostic_changes {
 319                 let db = self.analysis_host.raw_database();
 320                 let source_root = db.file_source_root(file_id);
 321                 if db.source_root(source_root).is_library {
 322                     // Only publish diagnostics for files in the workspace, not from crates.io deps
 323                     // or the sysroot.
 324                     // While theoretically these should never have errors, we have quite a few false
 325                     // positives particularly in the stdlib, and those diagnostics would stay around
 326                     // forever if we emitted them here.
 327                     continue;
 328                 }
 329
 330                 let uri = file_id_to_url(&self.vfs.read().0, file_id);
 331                 let mut diagnostics =
 332                     self.diagnostics.diagnostics_for(file_id).cloned().collect::<Vec<_>>();
 333
 334                 // VSCode assumes diagnostic messages to be non-empty strings, so we need to patch
 335                 // empty diagnostics. Neither the docs of VSCode nor the LSP spec say whether
 336                 // diagnostic messages are actually allowed to be empty or not and patching this
 337                 // in the VSCode client does not work as the assertion happens in the protocol
 338                 // conversion. So this hack is here to stay, and will be considered a hack
 339                 // until the LSP decides to state that empty messages are allowed.
 340
 341                 // See https://github.com/rust-lang/rust-analyzer/issues/11404
 342                 // See https://github.com/rust-lang/rust-analyzer/issues/13130
 343                 let patch_empty = |message: &mut String| {
 344                     if message.is_empty() {
 345                         *message = " ".to_string();
 346                     }
 347                 };
 348
 349                 for d in &mut diagnostics {
 350                     patch_empty(&mut d.message);
 351                     if let Some(dri) = &mut d.related_information {
 352                         for dri in dri {
 353                             patch_empty(&mut dri.message);
 354                         }
 355                     }
 356                 }
 357
 358                 let version = from_proto::vfs_path(&uri)
 359                     .map(|path| self.mem_docs.get(&path).map(|it| it.version))
 360                     .unwrap_or_default();
 361
 362                 self.send_notification::<lsp_types::notification::PublishDiagnostics>(
 363                     lsp_types::PublishDiagnosticsParams { uri, diagnostics, version },
 364                 );
 365             }
 366         }
 367
 368         if self.config.cargo_autoreload() {
 369             if let Some(cause) = self.fetch_workspaces_queue.should_start_op() {
 370                 self.fetch_workspaces(cause);
 371             }
 372         }
 373
 374         if !self.fetch_workspaces_queue.op_in_progress() {
 375             if let Some(cause) = self.fetch_build_data_queue.should_start_op() {
 376                 self.fetch_build_data(cause);
 377             }
 378         }
 379
 380         if let Some(cause) = self.prime_caches_queue.should_start_op() {
 381             tracing::debug!(%cause, "will prime caches");
 382             let num_worker_threads = self.config.prime_caches_num_threads();
 383
 384             self.task_pool.handle.spawn_with_sender({
 385                 let analysis = self.snapshot().analysis;
 386                 move |sender| {
 387                     sender.send(Task::PrimeCaches(PrimeCachesProgress::Begin)).unwrap();
 388                     let res = analysis.parallel_prime_caches(num_worker_threads, |progress| {
 389                         let report = PrimeCachesProgress::Report(progress);
 390                         sender.send(Task::PrimeCaches(report)).unwrap();
 391                     });
 392                     sender
 393                         .send(Task::PrimeCaches(PrimeCachesProgress::End {
 394                             cancelled: res.is_err(),
 395                         }))
 396                         .unwrap();
 397                 }
 398             });
 399         }
 400
 401         let status = self.current_status();
 402         if self.last_reported_status.as_ref() != Some(&status) {
 403             self.last_reported_status = Some(status.clone());
 404
 405             if let (lsp_ext::Health::Error, Some(message)) = (status.health, &status.message) {
 406                 self.show_message(lsp_types::MessageType::ERROR, message.clone());
 407             }
 408
 409             if self.config.server_status_notification() {
 410                 self.send_notification::<lsp_ext::ServerStatusNotification>(status);
 411             }
 412         }
 413
 414         let loop_duration = loop_start.elapsed();
 415         if loop_duration > Duration::from_millis(100) && was_quiescent {
 416             tracing::warn!("overly long loop turn: {:?}", loop_duration);
 417             self.poke_rust_analyzer_developer(format!(
 418                 "overly long loop turn: {:?}",
 419                 loop_duration
 420             ));
 421         }
 422         Ok(())
 423     }
 424
 425     fn handle_task(&mut self, prime_caches_progress: &mut Vec<PrimeCachesProgress>, task: Task) {
 426         match task {
 427             Task::Response(response) => self.respond(response),
 428             // Only retry requests that haven't been cancelled. Otherwise we do unnecessary work.
 429             Task::Retry(req) if !self.is_completed(&req) => self.on_request(req),
 430             Task::Retry(_) => (),
 431             Task::Diagnostics(diagnostics_per_file) => {
 432                 for (file_id, diagnostics) in diagnostics_per_file {
 433                     self.diagnostics.set_native_diagnostics(file_id, diagnostics)
 434                 }
 435             }
 436             Task::PrimeCaches(progress) => match progress {
 437                 PrimeCachesProgress::Begin => prime_caches_progress.push(progress),
 438                 PrimeCachesProgress::Report(_) => {
 439                     match prime_caches_progress.last_mut() {
 440                         Some(last @ PrimeCachesProgress::Report(_)) => {
 441                             // Coalesce subsequent update events.
 442                             *last = progress;
 443                         }
 444                         _ => prime_caches_progress.push(progress),
 445                     }
 446                 }
 447                 PrimeCachesProgress::End { .. } => prime_caches_progress.push(progress),
 448             },
 449             Task::FetchWorkspace(progress) => {
 450                 let (state, msg) = match progress {
 451                     ProjectWorkspaceProgress::Begin => (Progress::Begin, None),
 452                     ProjectWorkspaceProgress::Report(msg) => (Progress::Report, Some(msg)),
 453                     ProjectWorkspaceProgress::End(workspaces) => {
 454                         self.fetch_workspaces_queue.op_completed(Some(workspaces));
 455
 456                         let old = Arc::clone(&self.workspaces);
 457                         self.switch_workspaces("fetched workspace".to_string());
 458                         let workspaces_updated = !Arc::ptr_eq(&old, &self.workspaces);
 459
 460                         if self.config.run_build_scripts() && workspaces_updated {
 461                             self.fetch_build_data_queue.request_op(format!("workspace updated"));
 462                         }
 463
 464                         (Progress::End, None)
 465                     }
 466                 };
 467
 468                 self.report_progress("Fetching", state, msg, None, None);
 469             }
 470             Task::FetchBuildData(progress) => {
 471                 let (state, msg) = match progress {
 472                     BuildDataProgress::Begin => (Some(Progress::Begin), None),
 473                     BuildDataProgress::Report(msg) => (Some(Progress::Report), Some(msg)),
 474                     BuildDataProgress::End(build_data_result) => {
 475                         self.fetch_build_data_queue.op_completed(build_data_result);
 476
 477                         self.switch_workspaces("fetched build data".to_string());
 478
 479                         (Some(Progress::End), None)
 480                     }
 481                 };
 482
 483                 if let Some(state) = state {
 484                     self.report_progress("Loading", state, msg, None, None);
 485                 }
 486             }
 487         }
 488     }
 489
 490     fn handle_vfs_msg(&mut self, message: vfs::loader::Message) {
 491         match message {
 492             vfs::loader::Message::Loaded { files } => {
 493                 let vfs = &mut self.vfs.write().0;
 494                 for (path, contents) in files {
 495                     let path = VfsPath::from(path);
 496                     if !self.mem_docs.contains(&path) {
 497                         vfs.set_file_contents(path, contents);
 498                     }
 499                 }
 500             }
 501             vfs::loader::Message::Progress { n_total, n_done, config_version } => {
 502                 always!(config_version <= self.vfs_config_version);
 503
 504                 self.vfs_progress_config_version = config_version;
 505                 self.vfs_progress_n_total = n_total;
 506                 self.vfs_progress_n_done = n_done;
 507
 508                 let state = if n_done == 0 {
 509                     Progress::Begin
 510                 } else if n_done < n_total {
 511                     Progress::Report
 512                 } else {
 513                     assert_eq!(n_done, n_total);
 514                     Progress::End
 515                 };
 516                 self.report_progress(
 517                     "Roots Scanned",
 518                     state,
 519                     Some(format!("{}/{}", n_done, n_total)),
 520                     Some(Progress::fraction(n_done, n_total)),
 521                     None,
 522                 )
 523             }
 524         }
 525     }
 526
 527     fn handle_flycheck_msg(&mut self, message: flycheck::Message) {
 528         match message {
 529             flycheck::Message::AddDiagnostic { id, workspace_root, diagnostic } => {
 530                 let snap = self.snapshot();
 531                 let diagnostics = crate::diagnostics::to_proto::map_rust_diagnostic_to_lsp(
 532                     &self.config.diagnostics_map(),
 533                     &diagnostic,
 534                     &workspace_root,
 535                     &snap,
 536                 );
 537                 for diag in diagnostics {
 538                     match url_to_file_id(&self.vfs.read().0, &diag.url) {
 539                         Ok(file_id) => self.diagnostics.add_check_diagnostic(
 540                             id,
 541                             file_id,
 542                             diag.diagnostic,
 543                             diag.fix,
 544                         ),
 545                         Err(err) => {
 546                             tracing::error!(
 547                                 "flycheck {id}: File with cargo diagnostic not found in VFS: {}",
 548                                 err
 549                             );
 550                         }
 551                     };
 552                 }
 553             }
 554
 555             flycheck::Message::Progress { id, progress } => {
 556                 let (state, message) = match progress {
 557                     flycheck::Progress::DidStart => {
 558                         self.diagnostics.clear_check(id);
 559                         (Progress::Begin, None)
 560                     }
 561                     flycheck::Progress::DidCheckCrate(target) => (Progress::Report, Some(target)),
 562                     flycheck::Progress::DidCancel => (Progress::End, None),
 563                     flycheck::Progress::DidFailToRestart(err) => {
 564                         self.show_and_log_error(
 565                             "cargo check failed".to_string(),
 566                             Some(err.to_string()),
 567                         );
 568                         return;
 569                     }
 570                     flycheck::Progress::DidFinish(result) => {
 571                         if let Err(err) = result {
 572                             self.show_and_log_error(
 573                                 "cargo check failed".to_string(),
 574                                 Some(err.to_string()),
 575                             );
 576                         }
 577                         (Progress::End, None)
 578                     }
 579                 };
 580
 581                 // When we're running multiple flychecks, we have to include a disambiguator in
 582                 // the title, or the editor complains. Note that this is a user-facing string.
 583                 let title = if self.flycheck.len() == 1 {
 584                     match self.config.flycheck() {
 585                         Some(config) => format!("{}", config),
 586                         None => "cargo check".to_string(),
 587                     }
 588                 } else {
 589                     format!("cargo check (#{})", id + 1)
 590                 };
 591                 self.report_progress(
 592                     &title,
 593                     state,
 594                     message,
 595                     None,
 596                     Some(format!("rust-analyzer/checkOnSave/{}", id)),
 597                 );
 598             }
 599         }
 600     }
 601
 602     /// Registers and handles a request. This should only be called once per incoming request.
 603     fn on_new_request(&mut self, request_received: Instant, req: Request) {
 604         self.register_request(&req, request_received);
 605         self.on_request(req);
 606     }
 607
 608     /// Handles a request.
 609     fn on_request(&mut self, req: Request) {
 610         let mut dispatcher = RequestDispatcher { req: Some(req), global_state: self };
 611         dispatcher.on_sync_mut::<lsp_types::request::Shutdown>(|s, ()| {
 612             s.shutdown_requested = true;
 613             Ok(())
 614         });
 615
 616         if let RequestDispatcher { req: Some(req), global_state: this } = &mut dispatcher {
 617             if this.shutdown_requested {
 618                 this.respond(lsp_server::Response::new_err(
 619                     req.id.clone(),
 620                     lsp_server::ErrorCode::InvalidRequest as i32,
 621                     "Shutdown already requested.".to_owned(),
 622                 ));
 623                 return;
 624             }
 625
 626             // Avoid flashing a bunch of unresolved references during initial load.
 627             if this.workspaces.is_empty() && !this.is_quiescent() {
 628                 this.respond(lsp_server::Response::new_err(
 629                     req.id.clone(),
 630                     lsp_server::ErrorCode::ContentModified as i32,
 631                     "waiting for cargo metadata or cargo check".to_owned(),
 632                 ));
 633                 return;
 634             }
 635         }
 636
 637         dispatcher
 638             .on_sync_mut::<lsp_ext::ReloadWorkspace>(handlers::handle_workspace_reload)
 639             .on_sync_mut::<lsp_ext::MemoryUsage>(handlers::handle_memory_usage)
 640             .on_sync_mut::<lsp_ext::ShuffleCrateGraph>(handlers::handle_shuffle_crate_graph)
 641             .on_sync_mut::<lsp_ext::CancelFlycheck>(handlers::handle_cancel_flycheck)
 642             .on_sync::<lsp_ext::JoinLines>(handlers::handle_join_lines)
 643             .on_sync::<lsp_ext::OnEnter>(handlers::handle_on_enter)
 644             .on_sync::<lsp_types::request::SelectionRangeRequest>(handlers::handle_selection_range)
 645             .on_sync::<lsp_ext::MatchingBrace>(handlers::handle_matching_brace)
 646             .on::<lsp_ext::AnalyzerStatus>(handlers::handle_analyzer_status)
 647             .on::<lsp_ext::SyntaxTree>(handlers::handle_syntax_tree)
 648             .on::<lsp_ext::ViewHir>(handlers::handle_view_hir)
 649             .on::<lsp_ext::ViewFileText>(handlers::handle_view_file_text)
 650             .on::<lsp_ext::ViewCrateGraph>(handlers::handle_view_crate_graph)
 651             .on::<lsp_ext::ViewItemTree>(handlers::handle_view_item_tree)
 652             .on::<lsp_ext::ExpandMacro>(handlers::handle_expand_macro)
 653             .on::<lsp_ext::ParentModule>(handlers::handle_parent_module)
 654             .on::<lsp_ext::Runnables>(handlers::handle_runnables)
 655             .on::<lsp_ext::RelatedTests>(handlers::handle_related_tests)
 656             .on::<lsp_ext::CodeActionRequest>(handlers::handle_code_action)
 657             .on::<lsp_ext::CodeActionResolveRequest>(handlers::handle_code_action_resolve)
 658             .on::<lsp_ext::HoverRequest>(handlers::handle_hover)
 659             .on::<lsp_ext::ExternalDocs>(handlers::handle_open_docs)
 660             .on::<lsp_ext::OpenCargoToml>(handlers::handle_open_cargo_toml)
 661             .on::<lsp_ext::MoveItem>(handlers::handle_move_item)
 662             .on::<lsp_ext::WorkspaceSymbol>(handlers::handle_workspace_symbol)
 663             .on::<lsp_ext::OnTypeFormatting>(handlers::handle_on_type_formatting)
 664             .on::<lsp_types::request::DocumentSymbolRequest>(handlers::handle_document_symbol)
 665             .on::<lsp_types::request::GotoDefinition>(handlers::handle_goto_definition)
 666             .on::<lsp_types::request::GotoDeclaration>(handlers::handle_goto_declaration)
 667             .on::<lsp_types::request::GotoImplementation>(handlers::handle_goto_implementation)
 668             .on::<lsp_types::request::GotoTypeDefinition>(handlers::handle_goto_type_definition)
 669             .on::<lsp_types::request::InlayHintRequest>(handlers::handle_inlay_hints)
 670             .on::<lsp_types::request::InlayHintResolveRequest>(handlers::handle_inlay_hints_resolve)
 671             .on::<lsp_types::request::Completion>(handlers::handle_completion)
 672             .on::<lsp_types::request::ResolveCompletionItem>(handlers::handle_completion_resolve)
 673             .on::<lsp_types::request::CodeLensRequest>(handlers::handle_code_lens)
 674             .on::<lsp_types::request::CodeLensResolve>(handlers::handle_code_lens_resolve)
 675             .on::<lsp_types::request::FoldingRangeRequest>(handlers::handle_folding_range)
 676             .on::<lsp_types::request::SignatureHelpRequest>(handlers::handle_signature_help)
 677             .on::<lsp_types::request::PrepareRenameRequest>(handlers::handle_prepare_rename)
 678             .on::<lsp_types::request::Rename>(handlers::handle_rename)
 679             .on::<lsp_types::request::References>(handlers::handle_references)
 680             .on::<lsp_types::request::Formatting>(handlers::handle_formatting)
 681             .on::<lsp_types::request::RangeFormatting>(handlers::handle_range_formatting)
 682             .on::<lsp_types::request::DocumentHighlightRequest>(handlers::handle_document_highlight)
 683             .on::<lsp_types::request::CallHierarchyPrepare>(handlers::handle_call_hierarchy_prepare)
 684             .on::<lsp_types::request::CallHierarchyIncomingCalls>(
 685                 handlers::handle_call_hierarchy_incoming,
 686             )
 687             .on::<lsp_types::request::CallHierarchyOutgoingCalls>(
 688                 handlers::handle_call_hierarchy_outgoing,
 689             )
 690             .on::<lsp_types::request::SemanticTokensFullRequest>(
 691                 handlers::handle_semantic_tokens_full,
 692             )
 693             .on::<lsp_types::request::SemanticTokensFullDeltaRequest>(
 694                 handlers::handle_semantic_tokens_full_delta,
 695             )
 696             .on::<lsp_types::request::SemanticTokensRangeRequest>(
 697                 handlers::handle_semantic_tokens_range,
 698             )
 699             .on::<lsp_types::request::WillRenameFiles>(handlers::handle_will_rename_files)
 700             .on::<lsp_ext::Ssr>(handlers::handle_ssr)
 701             .finish();
 702     }
 703
 704     /// Handles an incoming notification.
 705     fn on_notification(&mut self, not: Notification) -> Result<()> {
 706         NotificationDispatcher { not: Some(not), global_state: self }
 707             .on::<lsp_types::notification::Cancel>(|this, params| {
 708                 let id: lsp_server::RequestId = match params.id {
 709                     lsp_types::NumberOrString::Number(id) => id.into(),
 710                     lsp_types::NumberOrString::String(id) => id.into(),
 711                 };
 712                 this.cancel(id);
 713                 Ok(())
 714             })?
 715             .on::<lsp_types::notification::WorkDoneProgressCancel>(|this, params| {
 716                 if let lsp_types::NumberOrString::String(s) = &params.token {
 717                     if let Some(id) = s.strip_prefix("rust-analyzer/checkOnSave/") {
 718                         if let Ok(id) = u32::from_str_radix(id, 10) {
 719                             if let Some(flycheck) = this.flycheck.get(id as usize) {
 720                                 flycheck.cancel();
 721                             }
 722                         }
 723                     }
 724                 }
 725                 // Just ignore this. It is OK to continue sending progress
 726                 // notifications for this token, as the client can't know when
 727                 // we accepted notification.
 728                 Ok(())
 729             })?
 730             .on::<lsp_types::notification::DidOpenTextDocument>(|this, params| {
 731                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 732                     let already_exists = this
 733                         .mem_docs
 734                         .insert(path.clone(), DocumentData::new(params.text_document.version))
 735                         .is_err();
 736                     if already_exists {
 737                         tracing::error!("duplicate DidOpenTextDocument: {}", path);
 738                     }
 739                     this.vfs
 740                         .write()
 741                         .0
 742                         .set_file_contents(path, Some(params.text_document.text.into_bytes()));
 743                 }
 744                 Ok(())
 745             })?
 746             .on::<lsp_types::notification::DidChangeTextDocument>(|this, params| {
 747                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 748                     match this.mem_docs.get_mut(&path) {
 749                         Some(doc) => {
 750                             // The version passed in DidChangeTextDocument is the version after all edits are applied
 751                             // so we should apply it before the vfs is notified.
 752                             doc.version = params.text_document.version;
 753                         }
 754                         None => {
 755                             tracing::error!("unexpected DidChangeTextDocument: {}", path);
 756                             return Ok(());
 757                         }
 758                     };
 759
 760                     let vfs = &mut this.vfs.write().0;
 761                     let file_id = vfs.file_id(&path).unwrap();
 762                     let text = apply_document_changes(
 763                         || std::str::from_utf8(vfs.file_contents(file_id)).unwrap().into(),
 764                         params.content_changes,
 765                     );
 766
 767                     vfs.set_file_contents(path, Some(text.into_bytes()));
 768                 }
 769                 Ok(())
 770             })?
 771             .on::<lsp_types::notification::DidCloseTextDocument>(|this, params| {
 772                 if let Ok(path) = from_proto::vfs_path(&params.text_document.uri) {
 773                     if this.mem_docs.remove(&path).is_err() {
 774                         tracing::error!("orphan DidCloseTextDocument: {}", path);
 775                     }
 776
 777                     this.semantic_tokens_cache.lock().remove(&params.text_document.uri);
 778
 779                     if let Some(path) = path.as_path() {
 780                         this.loader.handle.invalidate(path.to_path_buf());
 781                     }
 782                 }
 783                 Ok(())
 784             })?
 785             .on::<lsp_types::notification::DidSaveTextDocument>(|this, params| {
 786                 if let Ok(vfs_path) = from_proto::vfs_path(&params.text_document.uri) {
 787                     // Re-fetch workspaces if a workspace related file has changed
 788                     if let Some(abs_path) = vfs_path.as_path() {
 789                         if reload::should_refresh_for_change(&abs_path, ChangeKind::Modify) {
 790                             this.fetch_workspaces_queue
 791                                 .request_op(format!("DidSaveTextDocument {}", abs_path.display()));
 792                         }
 793                     }
 794
 795                     let file_id = this.vfs.read().0.file_id(&vfs_path);
 796                     if let Some(file_id) = file_id {
 797                         let world = this.snapshot();
 798                         let mut updated = false;
 799                         let task = move || -> std::result::Result<(), ide::Cancelled> {
 800                             // Trigger flychecks for all workspaces that depend on the saved file
 801                             // Crates containing or depending on the saved file
 802                             let crate_ids: Vec<_> = world
 803                                 .analysis
 804                                 .crates_for(file_id)?
 805                                 .into_iter()
 806                                 .flat_map(|id| world.analysis.transitive_rev_deps(id))
 807                                 .flatten()
 808                                 .sorted()
 809                                 .unique()
 810                                 .collect();
 811
 812                             let crate_root_paths: Vec<_> = crate_ids
 813                                 .iter()
 814                                 .filter_map(|&crate_id| {
 815                                     world
 816                                         .analysis
 817                                         .crate_root(crate_id)
 818                                         .map(|file_id| {
 819                                             world
 820                                                 .file_id_to_file_path(file_id)
 821                                                 .as_path()
 822                                                 .map(ToOwned::to_owned)
 823                                         })
 824                                         .transpose()
 825                                 })
 826                                 .collect::<ide::Cancellable<_>>()?;
 827                             let crate_root_paths: Vec<_> =
 828                                 crate_root_paths.iter().map(Deref::deref).collect();
 829
 830                             // Find all workspaces that have at least one target containing the saved file
 831                             let workspace_ids =
 832                                 world.workspaces.iter().enumerate().filter(|(_, ws)| match ws {
 833                                     project_model::ProjectWorkspace::Cargo { cargo, .. } => {
 834                                         cargo.packages().any(|pkg| {
 835                                             cargo[pkg].targets.iter().any(|&it| {
 836                                                 crate_root_paths.contains(&cargo[it].root.as_path())
 837                                             })
 838                                         })
 839                                     }
 840                                     project_model::ProjectWorkspace::Json { project, .. } => {
 841                                         project.crates().any(|(c, _)| {
 842                                             crate_ids.iter().any(|&crate_id| crate_id == c)
 843                                         })
 844                                     }
 845                                     project_model::ProjectWorkspace::DetachedFiles { .. } => false,
 846                                 });
 847
 848                             // Find and trigger corresponding flychecks
 849                             for flycheck in world.flycheck.iter() {
 850                                 for (id, _) in workspace_ids.clone() {
 851                                     if id == flycheck.id() {
 852                                         updated = true;
 853                                         flycheck.restart();
 854                                         continue;
 855                                     }
 856                                 }
 857                             }
 858                             // No specific flycheck was triggered, so let's trigger all of them.
 859                             if !updated {
 860                                 for flycheck in world.flycheck.iter() {
 861                                     flycheck.restart();
 862                                 }
 863                             }
 864                             Ok(())
 865                         };
 866                         this.task_pool.handle.spawn_with_sender(move |_| {
 867                             if let Err(e) = std::panic::catch_unwind(task) {
 868                                 tracing::error!("DidSaveTextDocument flycheck task panicked: {e:?}")
 869                             }
 870                         });
 871                         return Ok(());
 872                     }
 873                 }
 874
 875                 // No specific flycheck was triggered, so let's trigger all of them.
 876                 for flycheck in this.flycheck.iter() {
 877                     flycheck.restart();
 878                 }
 879                 Ok(())
 880             })?
 881             .on::<lsp_types::notification::DidChangeConfiguration>(|this, _params| {
 882                 // As stated in https://github.com/microsoft/language-server-protocol/issues/676,
 883                 // this notification's parameters should be ignored and the actual config queried separately.
 884                 this.send_request::<lsp_types::request::WorkspaceConfiguration>(
 885                     lsp_types::ConfigurationParams {
 886                         items: vec![lsp_types::ConfigurationItem {
 887                             scope_uri: None,
 888                             section: Some("rust-analyzer".to_string()),
 889                         }],
 890                     },
 891                     |this, resp| {
 892                         tracing::debug!("config update response: '{:?}", resp);
 893                         let lsp_server::Response { error, result, .. } = resp;
 894
 895                         match (error, result) {
 896                             (Some(err), _) => {
 897                                 tracing::error!("failed to fetch the server settings: {:?}", err)
 898                             }
 899                             (None, Some(mut configs)) => {
 900                                 if let Some(json) = configs.get_mut(0) {
 901                                     // Note that json can be null according to the spec if the client can't
 902                                     // provide a configuration. This is handled in Config::update below.
 903                                     let mut config = Config::clone(&*this.config);
 904                                     if let Err(error) = config.update(json.take()) {
 905                                         this.show_message(
 906                                             lsp_types::MessageType::WARNING,
 907                                             error.to_string(),
 908                                         );
 909                                     }
 910                                     this.update_configuration(config);
 911                                 }
 912                             }
 913                             (None, None) => tracing::error!(
 914                                 "received empty server settings response from the client"
 915                             ),
 916                         }
 917                     },
 918                 );
 919
 920                 Ok(())
 921             })?
 922             .on::<lsp_types::notification::DidChangeWatchedFiles>(|this, params| {
 923                 for change in params.changes {
 924                     if let Ok(path) = from_proto::abs_path(&change.uri) {
 925                         this.loader.handle.invalidate(path);
 926                     }
 927                 }
 928                 Ok(())
 929             })?
 930             .finish();
 931         Ok(())
 932     }
 933
 934     fn update_diagnostics(&mut self) {
 935         let subscriptions = self
 936             .mem_docs
 937             .iter()
 938             .map(|path| self.vfs.read().0.file_id(path).unwrap())
 939             .collect::<Vec<_>>();
 940
 941         tracing::trace!("updating notifications for {:?}", subscriptions);
 942
 943         let snapshot = self.snapshot();
 944         self.task_pool.handle.spawn(move || {
 945             let diagnostics = subscriptions
 946                 .into_iter()
 947                 .filter_map(|file_id| {
 948                     handlers::publish_diagnostics(&snapshot, file_id)
 949                         .ok()
 950                         .map(|diags| (file_id, diags))
 951                 })
 952                 .collect::<Vec<_>>();
 953             Task::Diagnostics(diagnostics)
 954         })
 955     }
 956 }