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