lsp.rs

   1mod input_handler;
   2
   3pub use lsp_types::request::*;
   4pub use lsp_types::*;
   5
   6use anyhow::{Context as _, Result, anyhow};
   7use collections::{BTreeMap, HashMap};
   8use futures::{
   9    AsyncRead, AsyncWrite, Future, FutureExt,
  10    channel::oneshot::{self, Canceled},
  11    io::BufWriter,
  12    select,
  13};
  14use gpui::{App, AppContext as _, AsyncApp, BackgroundExecutor, SharedString, Task};
  15use notification::DidChangeWorkspaceFolders;
  16use parking_lot::{Mutex, RwLock};
  17use postage::{barrier, prelude::Stream};
  18use schemars::JsonSchema;
  19use serde::{Deserialize, Serialize, de::DeserializeOwned};
  20use serde_json::{Value, json, value::RawValue};
  21use smol::{
  22    channel,
  23    io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
  24    process::Child,
  25};
  26
  27use std::{
  28    collections::BTreeSet,
  29    ffi::{OsStr, OsString},
  30    fmt,
  31    io::Write,
  32    ops::DerefMut,
  33    path::PathBuf,
  34    pin::Pin,
  35    sync::{
  36        Arc, Weak,
  37        atomic::{AtomicI32, Ordering::SeqCst},
  38    },
  39    task::Poll,
  40    time::{Duration, Instant},
  41};
  42use std::{path::Path, process::Stdio};
  43use util::{ConnectionResult, ResultExt, TryFutureExt, redact};
  44
  45const JSON_RPC_VERSION: &str = "2.0";
  46const CONTENT_LEN_HEADER: &str = "Content-Length: ";
  47
  48pub const LSP_REQUEST_TIMEOUT: Duration = Duration::from_secs(60 * 2);
  49const SERVER_SHUTDOWN_TIMEOUT: Duration = Duration::from_secs(5);
  50
  51type NotificationHandler = Box<dyn Send + FnMut(Option<RequestId>, Value, &mut AsyncApp)>;
  52type ResponseHandler = Box<dyn Send + FnOnce(Result<String, Error>)>;
  53type IoHandler = Box<dyn Send + FnMut(IoKind, &str)>;
  54
  55/// Kind of language server stdio given to an IO handler.
  56#[derive(Debug, Clone, Copy)]
  57pub enum IoKind {
  58    StdOut,
  59    StdIn,
  60    StdErr,
  61}
  62
  63/// Represents a launchable language server. This can either be a standalone binary or the path
  64/// to a runtime with arguments to instruct it to launch the actual language server file.
  65#[derive(Clone, Serialize)]
  66pub struct LanguageServerBinary {
  67    pub path: PathBuf,
  68    pub arguments: Vec<OsString>,
  69    pub env: Option<HashMap<String, String>>,
  70}
  71
  72/// Configures the search (and installation) of language servers.
  73#[derive(Debug, Clone)]
  74pub struct LanguageServerBinaryOptions {
  75    /// Whether the adapter should look at the users system
  76    pub allow_path_lookup: bool,
  77    /// Whether the adapter should download its own version
  78    pub allow_binary_download: bool,
  79    /// Whether the adapter should download a pre-release version
  80    pub pre_release: bool,
  81}
  82
  83struct NotificationSerializer(Box<dyn FnOnce() -> String + Send + Sync>);
  84
  85/// A running language server process.
  86pub struct LanguageServer {
  87    server_id: LanguageServerId,
  88    next_id: AtomicI32,
  89    outbound_tx: channel::Sender<String>,
  90    notification_tx: channel::Sender<NotificationSerializer>,
  91    name: LanguageServerName,
  92    process_name: Arc<str>,
  93    binary: LanguageServerBinary,
  94    capabilities: RwLock<ServerCapabilities>,
  95    /// Configuration sent to the server, stored for display in the language server logs
  96    /// buffer. This is represented as the message sent to the LSP in order to avoid cloning it (can
  97    /// be large in cases like sending schemas to the json server).
  98    configuration: Arc<DidChangeConfigurationParams>,
  99    code_action_kinds: Option<Vec<CodeActionKind>>,
 100    notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
 101    response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
 102    io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 103    executor: BackgroundExecutor,
 104    #[allow(clippy::type_complexity)]
 105    io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
 106    output_done_rx: Mutex<Option<barrier::Receiver>>,
 107    server: Arc<Mutex<Option<Child>>>,
 108    workspace_folders: Option<Arc<Mutex<BTreeSet<Uri>>>>,
 109    root_uri: Uri,
 110}
 111
 112#[derive(Clone, Debug, PartialEq, Eq, Hash)]
 113pub enum LanguageServerSelector {
 114    Id(LanguageServerId),
 115    Name(LanguageServerName),
 116}
 117
 118/// Identifies a running language server.
 119#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 120#[repr(transparent)]
 121pub struct LanguageServerId(pub usize);
 122
 123impl LanguageServerId {
 124    pub fn from_proto(id: u64) -> Self {
 125        Self(id as usize)
 126    }
 127
 128    pub fn to_proto(self) -> u64 {
 129        self.0 as u64
 130    }
 131}
 132
 133/// A name of a language server.
 134#[derive(
 135    Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Deserialize, Serialize, JsonSchema,
 136)]
 137#[serde(transparent)]
 138pub struct LanguageServerName(pub SharedString);
 139
 140impl std::fmt::Display for LanguageServerName {
 141    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 142        std::fmt::Display::fmt(&self.0, f)
 143    }
 144}
 145
 146impl AsRef<str> for LanguageServerName {
 147    fn as_ref(&self) -> &str {
 148        self.0.as_ref()
 149    }
 150}
 151
 152impl AsRef<OsStr> for LanguageServerName {
 153    fn as_ref(&self) -> &OsStr {
 154        self.0.as_ref().as_ref()
 155    }
 156}
 157
 158impl LanguageServerName {
 159    pub const fn new_static(s: &'static str) -> Self {
 160        Self(SharedString::new_static(s))
 161    }
 162
 163    pub fn from_proto(s: String) -> Self {
 164        Self(s.into())
 165    }
 166}
 167
 168impl<'a> From<&'a str> for LanguageServerName {
 169    fn from(str: &'a str) -> LanguageServerName {
 170        LanguageServerName(str.to_string().into())
 171    }
 172}
 173
 174impl PartialEq<str> for LanguageServerName {
 175    fn eq(&self, other: &str) -> bool {
 176        self.0 == other
 177    }
 178}
 179
 180/// Handle to a language server RPC activity subscription.
 181pub enum Subscription {
 182    Notification {
 183        method: &'static str,
 184        notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
 185    },
 186    Io {
 187        id: i32,
 188        io_handlers: Option<Weak<Mutex<HashMap<i32, IoHandler>>>>,
 189    },
 190}
 191
 192/// Language server protocol RPC request message ID.
 193///
 194/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 195#[derive(Debug, Clone, Eq, PartialEq, Hash, Serialize, Deserialize)]
 196#[serde(untagged)]
 197pub enum RequestId {
 198    Int(i32),
 199    Str(String),
 200}
 201
 202/// Language server protocol RPC request message.
 203///
 204/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 205#[derive(Serialize, Deserialize)]
 206pub struct Request<'a, T> {
 207    jsonrpc: &'static str,
 208    id: RequestId,
 209    method: &'a str,
 210    params: T,
 211}
 212
 213/// Language server protocol RPC request response message before it is deserialized into a concrete type.
 214#[derive(Serialize, Deserialize)]
 215struct AnyResponse<'a> {
 216    jsonrpc: &'a str,
 217    id: RequestId,
 218    #[serde(default)]
 219    error: Option<Error>,
 220    #[serde(borrow)]
 221    result: Option<&'a RawValue>,
 222}
 223
 224/// Language server protocol RPC request response message.
 225///
 226/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#responseMessage)
 227#[derive(Serialize)]
 228struct Response<T> {
 229    jsonrpc: &'static str,
 230    id: RequestId,
 231    #[serde(flatten)]
 232    value: LspResult<T>,
 233}
 234
 235#[derive(Serialize)]
 236#[serde(rename_all = "snake_case")]
 237enum LspResult<T> {
 238    #[serde(rename = "result")]
 239    Ok(Option<T>),
 240    Error(Option<Error>),
 241}
 242
 243/// Language server protocol RPC notification message.
 244///
 245/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
 246#[derive(Serialize, Deserialize)]
 247struct Notification<'a, T> {
 248    jsonrpc: &'static str,
 249    #[serde(borrow)]
 250    method: &'a str,
 251    params: T,
 252}
 253
 254/// Language server RPC notification message before it is deserialized into a concrete type.
 255#[derive(Debug, Clone, Deserialize)]
 256struct NotificationOrRequest {
 257    #[serde(default)]
 258    id: Option<RequestId>,
 259    method: String,
 260    #[serde(default)]
 261    params: Option<Value>,
 262}
 263
 264#[derive(Debug, Serialize, Deserialize)]
 265struct Error {
 266    code: i64,
 267    message: String,
 268    #[serde(default)]
 269    data: Option<serde_json::Value>,
 270}
 271
 272pub trait LspRequestFuture<O>: Future<Output = ConnectionResult<O>> {
 273    fn id(&self) -> i32;
 274}
 275
 276struct LspRequest<F> {
 277    id: i32,
 278    request: F,
 279}
 280
 281impl<F> LspRequest<F> {
 282    pub fn new(id: i32, request: F) -> Self {
 283        Self { id, request }
 284    }
 285}
 286
 287impl<F: Future> Future for LspRequest<F> {
 288    type Output = F::Output;
 289
 290    fn poll(self: Pin<&mut Self>, cx: &mut std::task::Context<'_>) -> Poll<Self::Output> {
 291        // SAFETY: This is standard pin projection, we're pinned so our fields must be pinned.
 292        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().request) };
 293        inner.poll(cx)
 294    }
 295}
 296
 297impl<F, O> LspRequestFuture<O> for LspRequest<F>
 298where
 299    F: Future<Output = ConnectionResult<O>>,
 300{
 301    fn id(&self) -> i32 {
 302        self.id
 303    }
 304}
 305
 306/// Combined capabilities of the server and the adapter.
 307#[derive(Debug)]
 308pub struct AdapterServerCapabilities {
 309    // Reported capabilities by the server
 310    pub server_capabilities: ServerCapabilities,
 311    // List of code actions supported by the LspAdapter matching the server
 312    pub code_action_kinds: Option<Vec<CodeActionKind>>,
 313}
 314
 315impl LanguageServer {
 316    /// Starts a language server process.
 317    pub async fn new(
 318        stderr_capture: Arc<Mutex<Option<String>>>,
 319        server_id: LanguageServerId,
 320        server_name: LanguageServerName,
 321        binary: LanguageServerBinary,
 322        root_path: &Path,
 323        code_action_kinds: Option<Vec<CodeActionKind>>,
 324        workspace_folders: Option<Arc<Mutex<BTreeSet<Uri>>>>,
 325        cx: &mut AsyncApp,
 326    ) -> Result<Self> {
 327        let working_dir = if root_path.is_dir() {
 328            root_path
 329        } else {
 330            root_path.parent().unwrap_or_else(|| Path::new("/"))
 331        };
 332        let root_uri = Uri::from_file_path(&working_dir)
 333            .map_err(|()| anyhow!("{working_dir:?} is not a valid URI"))?;
 334        log::info!(
 335            "starting language server process. binary path: \
 336            {:?}, working directory: {:?}, args: {:?}",
 337            binary.path,
 338            working_dir,
 339            &binary.arguments
 340        );
 341        let mut server = cx
 342            .background_executor()
 343            .await_on_background(async {
 344                let mut command = util::command::new_smol_command(&binary.path);
 345                command
 346                    .current_dir(working_dir)
 347                    .args(&binary.arguments)
 348                    .envs(binary.env.clone().unwrap_or_default())
 349                    .stdin(Stdio::piped())
 350                    .stdout(Stdio::piped())
 351                    .stderr(Stdio::piped())
 352                    .kill_on_drop(true);
 353                command
 354                    .spawn()
 355                    .with_context(|| format!("failed to spawn command {command:?}",))
 356            })
 357            .await?;
 358
 359        let stdin = server.stdin.take().unwrap();
 360        let stdout = server.stdout.take().unwrap();
 361        let stderr = server.stderr.take().unwrap();
 362        let server = Self::new_internal(
 363            server_id,
 364            server_name,
 365            stdin,
 366            stdout,
 367            Some(stderr),
 368            stderr_capture,
 369            Some(server),
 370            code_action_kinds,
 371            binary,
 372            root_uri,
 373            workspace_folders,
 374            cx,
 375            move |notification| {
 376                log::info!(
 377                    "Language server with id {} sent unhandled notification {}:\n{}",
 378                    server_id,
 379                    notification.method,
 380                    serde_json::to_string_pretty(&notification.params).unwrap(),
 381                );
 382                false
 383            },
 384        );
 385
 386        Ok(server)
 387    }
 388
 389    fn new_internal<Stdin, Stdout, Stderr, F>(
 390        server_id: LanguageServerId,
 391        server_name: LanguageServerName,
 392        stdin: Stdin,
 393        stdout: Stdout,
 394        stderr: Option<Stderr>,
 395        stderr_capture: Arc<Mutex<Option<String>>>,
 396        server: Option<Child>,
 397        code_action_kinds: Option<Vec<CodeActionKind>>,
 398        binary: LanguageServerBinary,
 399        root_uri: Uri,
 400        workspace_folders: Option<Arc<Mutex<BTreeSet<Uri>>>>,
 401        cx: &mut AsyncApp,
 402        on_unhandled_notification: F,
 403    ) -> Self
 404    where
 405        Stdin: AsyncWrite + Unpin + Send + 'static,
 406        Stdout: AsyncRead + Unpin + Send + 'static,
 407        Stderr: AsyncRead + Unpin + Send + 'static,
 408        F: Fn(&NotificationOrRequest) -> bool + 'static + Send + Sync + Clone,
 409    {
 410        let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
 411        let (output_done_tx, output_done_rx) = barrier::channel();
 412        let notification_handlers =
 413            Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
 414        let response_handlers =
 415            Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
 416        let io_handlers = Arc::new(Mutex::new(HashMap::default()));
 417
 418        let stdout_input_task = cx.spawn({
 419            let unhandled_notification_wrapper = {
 420                let response_channel = outbound_tx.clone();
 421                async move |msg: NotificationOrRequest| {
 422                    let did_handle = on_unhandled_notification(&msg);
 423                    if !did_handle && let Some(message_id) = msg.id {
 424                        let response = AnyResponse {
 425                            jsonrpc: JSON_RPC_VERSION,
 426                            id: message_id,
 427                            error: Some(Error {
 428                                code: -32601,
 429                                message: format!("Unrecognized method `{}`", msg.method),
 430                                data: None,
 431                            }),
 432                            result: None,
 433                        };
 434                        if let Ok(response) = serde_json::to_string(&response) {
 435                            response_channel.send(response).await.ok();
 436                        }
 437                    }
 438                }
 439            };
 440            let notification_handlers = notification_handlers.clone();
 441            let response_handlers = response_handlers.clone();
 442            let io_handlers = io_handlers.clone();
 443            async move |cx| {
 444                Self::handle_incoming_messages(
 445                    stdout,
 446                    unhandled_notification_wrapper,
 447                    notification_handlers,
 448                    response_handlers,
 449                    io_handlers,
 450                    cx,
 451                )
 452                .log_err()
 453                .await
 454            }
 455        });
 456        let stderr_input_task = stderr
 457            .map(|stderr| {
 458                let io_handlers = io_handlers.clone();
 459                let stderr_captures = stderr_capture.clone();
 460                cx.background_spawn(async move {
 461                    Self::handle_stderr(stderr, io_handlers, stderr_captures)
 462                        .log_err()
 463                        .await
 464                })
 465            })
 466            .unwrap_or_else(|| Task::ready(None));
 467        let input_task = cx.background_spawn(async move {
 468            let (stdout, stderr) = futures::join!(stdout_input_task, stderr_input_task);
 469            stdout.or(stderr)
 470        });
 471        let output_task = cx.background_spawn({
 472            Self::handle_outgoing_messages(
 473                stdin,
 474                outbound_rx,
 475                output_done_tx,
 476                response_handlers.clone(),
 477                io_handlers.clone(),
 478            )
 479            .log_err()
 480        });
 481
 482        let configuration = DidChangeConfigurationParams {
 483            settings: Value::Null,
 484        }
 485        .into();
 486
 487        let (notification_tx, notification_rx) = channel::unbounded::<NotificationSerializer>();
 488        cx.background_spawn({
 489            let outbound_tx = outbound_tx.clone();
 490            async move {
 491                while let Ok(serializer) = notification_rx.recv().await {
 492                    let serialized = (serializer.0)();
 493                    let Ok(_) = outbound_tx.send(serialized).await else {
 494                        return;
 495                    };
 496                }
 497                outbound_tx.close();
 498            }
 499        })
 500        .detach();
 501        Self {
 502            server_id,
 503            notification_handlers,
 504            notification_tx,
 505            response_handlers,
 506            io_handlers,
 507            name: server_name,
 508            process_name: binary
 509                .path
 510                .file_name()
 511                .map(|name| Arc::from(name.to_string_lossy()))
 512                .unwrap_or_default(),
 513            binary,
 514            capabilities: Default::default(),
 515            configuration,
 516            code_action_kinds,
 517            next_id: Default::default(),
 518            outbound_tx,
 519            executor: cx.background_executor().clone(),
 520            io_tasks: Mutex::new(Some((input_task, output_task))),
 521            output_done_rx: Mutex::new(Some(output_done_rx)),
 522            server: Arc::new(Mutex::new(server)),
 523            workspace_folders,
 524            root_uri,
 525        }
 526    }
 527
 528    /// List of code action kinds this language server reports being able to emit.
 529    pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
 530        self.code_action_kinds.clone()
 531    }
 532
 533    async fn handle_incoming_messages<Stdout>(
 534        stdout: Stdout,
 535        on_unhandled_notification: impl AsyncFn(NotificationOrRequest) + 'static + Send,
 536        notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
 537        response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
 538        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 539        cx: &mut AsyncApp,
 540    ) -> anyhow::Result<()>
 541    where
 542        Stdout: AsyncRead + Unpin + Send + 'static,
 543    {
 544        use smol::stream::StreamExt;
 545        let stdout = BufReader::new(stdout);
 546        let _clear_response_handlers = util::defer({
 547            let response_handlers = response_handlers.clone();
 548            move || {
 549                response_handlers.lock().take();
 550            }
 551        });
 552        let mut input_handler = input_handler::LspStdoutHandler::new(
 553            stdout,
 554            response_handlers,
 555            io_handlers,
 556            cx.background_executor().clone(),
 557        );
 558
 559        while let Some(msg) = input_handler.incoming_messages.next().await {
 560            let unhandled_message = {
 561                let mut notification_handlers = notification_handlers.lock();
 562                if let Some(handler) = notification_handlers.get_mut(msg.method.as_str()) {
 563                    handler(msg.id, msg.params.unwrap_or(Value::Null), cx);
 564                    None
 565                } else {
 566                    Some(msg)
 567                }
 568            };
 569
 570            if let Some(msg) = unhandled_message {
 571                on_unhandled_notification(msg).await;
 572            }
 573
 574            // Don't starve the main thread when receiving lots of notifications at once.
 575            smol::future::yield_now().await;
 576        }
 577        input_handler.loop_handle.await
 578    }
 579
 580    async fn handle_stderr<Stderr>(
 581        stderr: Stderr,
 582        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 583        stderr_capture: Arc<Mutex<Option<String>>>,
 584    ) -> anyhow::Result<()>
 585    where
 586        Stderr: AsyncRead + Unpin + Send + 'static,
 587    {
 588        let mut stderr = BufReader::new(stderr);
 589        let mut buffer = Vec::new();
 590
 591        loop {
 592            buffer.clear();
 593
 594            let bytes_read = stderr.read_until(b'\n', &mut buffer).await?;
 595            if bytes_read == 0 {
 596                return Ok(());
 597            }
 598
 599            if let Ok(message) = std::str::from_utf8(&buffer) {
 600                log::trace!("incoming stderr message:{message}");
 601                for handler in io_handlers.lock().values_mut() {
 602                    handler(IoKind::StdErr, message);
 603                }
 604
 605                if let Some(stderr) = stderr_capture.lock().as_mut() {
 606                    stderr.push_str(message);
 607                }
 608            }
 609
 610            // Don't starve the main thread when receiving lots of messages at once.
 611            smol::future::yield_now().await;
 612        }
 613    }
 614
 615    async fn handle_outgoing_messages<Stdin>(
 616        stdin: Stdin,
 617        outbound_rx: channel::Receiver<String>,
 618        output_done_tx: barrier::Sender,
 619        response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
 620        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 621    ) -> anyhow::Result<()>
 622    where
 623        Stdin: AsyncWrite + Unpin + Send + 'static,
 624    {
 625        let mut stdin = BufWriter::new(stdin);
 626        let _clear_response_handlers = util::defer({
 627            let response_handlers = response_handlers.clone();
 628            move || {
 629                response_handlers.lock().take();
 630            }
 631        });
 632        let mut content_len_buffer = Vec::new();
 633        while let Ok(message) = outbound_rx.recv().await {
 634            log::trace!("outgoing message:{}", message);
 635            for handler in io_handlers.lock().values_mut() {
 636                handler(IoKind::StdIn, &message);
 637            }
 638
 639            content_len_buffer.clear();
 640            write!(content_len_buffer, "{}", message.len()).unwrap();
 641            stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
 642            stdin.write_all(&content_len_buffer).await?;
 643            stdin.write_all("\r\n\r\n".as_bytes()).await?;
 644            stdin.write_all(message.as_bytes()).await?;
 645            stdin.flush().await?;
 646        }
 647        drop(output_done_tx);
 648        Ok(())
 649    }
 650
 651    pub fn default_initialize_params(&self, pull_diagnostics: bool, cx: &App) -> InitializeParams {
 652        let workspace_folders = self.workspace_folders.as_ref().map_or_else(
 653            || {
 654                vec![WorkspaceFolder {
 655                    name: Default::default(),
 656                    uri: self.root_uri.clone(),
 657                }]
 658            },
 659            |folders| {
 660                folders
 661                    .lock()
 662                    .iter()
 663                    .cloned()
 664                    .map(|uri| WorkspaceFolder {
 665                        name: Default::default(),
 666                        uri,
 667                    })
 668                    .collect()
 669            },
 670        );
 671
 672        #[allow(deprecated)]
 673        InitializeParams {
 674            process_id: Some(std::process::id()),
 675            root_path: None,
 676            root_uri: Some(self.root_uri.clone()),
 677            initialization_options: None,
 678            capabilities: ClientCapabilities {
 679                general: Some(GeneralClientCapabilities {
 680                    position_encodings: Some(vec![PositionEncodingKind::UTF16]),
 681                    ..GeneralClientCapabilities::default()
 682                }),
 683                workspace: Some(WorkspaceClientCapabilities {
 684                    configuration: Some(true),
 685                    did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
 686                        dynamic_registration: Some(true),
 687                        relative_pattern_support: Some(true),
 688                    }),
 689                    did_change_configuration: Some(DynamicRegistrationClientCapabilities {
 690                        dynamic_registration: Some(true),
 691                    }),
 692                    workspace_folders: Some(true),
 693                    symbol: Some(WorkspaceSymbolClientCapabilities {
 694                        resolve_support: None,
 695                        dynamic_registration: Some(true),
 696                        ..WorkspaceSymbolClientCapabilities::default()
 697                    }),
 698                    inlay_hint: Some(InlayHintWorkspaceClientCapabilities {
 699                        refresh_support: Some(true),
 700                    }),
 701                    diagnostics: Some(DiagnosticWorkspaceClientCapabilities {
 702                        refresh_support: Some(true),
 703                    })
 704                    .filter(|_| pull_diagnostics),
 705                    code_lens: Some(CodeLensWorkspaceClientCapabilities {
 706                        refresh_support: Some(true),
 707                    }),
 708                    workspace_edit: Some(WorkspaceEditClientCapabilities {
 709                        resource_operations: Some(vec![
 710                            ResourceOperationKind::Create,
 711                            ResourceOperationKind::Rename,
 712                            ResourceOperationKind::Delete,
 713                        ]),
 714                        document_changes: Some(true),
 715                        snippet_edit_support: Some(true),
 716                        ..WorkspaceEditClientCapabilities::default()
 717                    }),
 718                    file_operations: Some(WorkspaceFileOperationsClientCapabilities {
 719                        dynamic_registration: Some(true),
 720                        did_rename: Some(true),
 721                        will_rename: Some(true),
 722                        ..WorkspaceFileOperationsClientCapabilities::default()
 723                    }),
 724                    apply_edit: Some(true),
 725                    execute_command: Some(ExecuteCommandClientCapabilities {
 726                        dynamic_registration: Some(true),
 727                    }),
 728                    ..WorkspaceClientCapabilities::default()
 729                }),
 730                text_document: Some(TextDocumentClientCapabilities {
 731                    definition: Some(GotoCapability {
 732                        link_support: Some(true),
 733                        dynamic_registration: Some(true),
 734                    }),
 735                    code_action: Some(CodeActionClientCapabilities {
 736                        code_action_literal_support: Some(CodeActionLiteralSupport {
 737                            code_action_kind: CodeActionKindLiteralSupport {
 738                                value_set: vec![
 739                                    CodeActionKind::REFACTOR.as_str().into(),
 740                                    CodeActionKind::QUICKFIX.as_str().into(),
 741                                    CodeActionKind::SOURCE.as_str().into(),
 742                                ],
 743                            },
 744                        }),
 745                        data_support: Some(true),
 746                        resolve_support: Some(CodeActionCapabilityResolveSupport {
 747                            properties: vec![
 748                                "kind".to_string(),
 749                                "diagnostics".to_string(),
 750                                "isPreferred".to_string(),
 751                                "disabled".to_string(),
 752                                "edit".to_string(),
 753                                "command".to_string(),
 754                            ],
 755                        }),
 756                        dynamic_registration: Some(true),
 757                        ..CodeActionClientCapabilities::default()
 758                    }),
 759                    completion: Some(CompletionClientCapabilities {
 760                        completion_item: Some(CompletionItemCapability {
 761                            snippet_support: Some(true),
 762                            resolve_support: Some(CompletionItemCapabilityResolveSupport {
 763                                properties: vec![
 764                                    "additionalTextEdits".to_string(),
 765                                    "command".to_string(),
 766                                    "documentation".to_string(),
 767                                    // NB: Do not have this resolved, otherwise Zed becomes slow to complete things
 768                                    // "textEdit".to_string(),
 769                                ],
 770                            }),
 771                            deprecated_support: Some(true),
 772                            tag_support: Some(TagSupport {
 773                                value_set: vec![CompletionItemTag::DEPRECATED],
 774                            }),
 775                            insert_replace_support: Some(true),
 776                            label_details_support: Some(true),
 777                            insert_text_mode_support: Some(InsertTextModeSupport {
 778                                value_set: vec![
 779                                    InsertTextMode::AS_IS,
 780                                    InsertTextMode::ADJUST_INDENTATION,
 781                                ],
 782                            }),
 783                            documentation_format: Some(vec![
 784                                MarkupKind::Markdown,
 785                                MarkupKind::PlainText,
 786                            ]),
 787                            ..CompletionItemCapability::default()
 788                        }),
 789                        insert_text_mode: Some(InsertTextMode::ADJUST_INDENTATION),
 790                        completion_list: Some(CompletionListCapability {
 791                            item_defaults: Some(vec![
 792                                "commitCharacters".to_owned(),
 793                                "editRange".to_owned(),
 794                                "insertTextMode".to_owned(),
 795                                "insertTextFormat".to_owned(),
 796                                "data".to_owned(),
 797                            ]),
 798                        }),
 799                        context_support: Some(true),
 800                        dynamic_registration: Some(true),
 801                        ..CompletionClientCapabilities::default()
 802                    }),
 803                    rename: Some(RenameClientCapabilities {
 804                        prepare_support: Some(true),
 805                        prepare_support_default_behavior: Some(
 806                            PrepareSupportDefaultBehavior::IDENTIFIER,
 807                        ),
 808                        dynamic_registration: Some(true),
 809                        ..RenameClientCapabilities::default()
 810                    }),
 811                    hover: Some(HoverClientCapabilities {
 812                        content_format: Some(vec![MarkupKind::Markdown]),
 813                        dynamic_registration: Some(true),
 814                    }),
 815                    inlay_hint: Some(InlayHintClientCapabilities {
 816                        resolve_support: Some(InlayHintResolveClientCapabilities {
 817                            properties: vec![
 818                                "textEdits".to_string(),
 819                                "tooltip".to_string(),
 820                                "label.tooltip".to_string(),
 821                                "label.location".to_string(),
 822                                "label.command".to_string(),
 823                            ],
 824                        }),
 825                        dynamic_registration: Some(true),
 826                    }),
 827                    publish_diagnostics: Some(PublishDiagnosticsClientCapabilities {
 828                        related_information: Some(true),
 829                        version_support: Some(true),
 830                        data_support: Some(true),
 831                        tag_support: Some(TagSupport {
 832                            value_set: vec![DiagnosticTag::UNNECESSARY, DiagnosticTag::DEPRECATED],
 833                        }),
 834                        code_description_support: Some(true),
 835                    }),
 836                    formatting: Some(DynamicRegistrationClientCapabilities {
 837                        dynamic_registration: Some(true),
 838                    }),
 839                    range_formatting: Some(DynamicRegistrationClientCapabilities {
 840                        dynamic_registration: Some(true),
 841                    }),
 842                    on_type_formatting: Some(DynamicRegistrationClientCapabilities {
 843                        dynamic_registration: Some(true),
 844                    }),
 845                    signature_help: Some(SignatureHelpClientCapabilities {
 846                        signature_information: Some(SignatureInformationSettings {
 847                            documentation_format: Some(vec![
 848                                MarkupKind::Markdown,
 849                                MarkupKind::PlainText,
 850                            ]),
 851                            parameter_information: Some(ParameterInformationSettings {
 852                                label_offset_support: Some(true),
 853                            }),
 854                            active_parameter_support: Some(true),
 855                        }),
 856                        dynamic_registration: Some(true),
 857                        ..SignatureHelpClientCapabilities::default()
 858                    }),
 859                    synchronization: Some(TextDocumentSyncClientCapabilities {
 860                        did_save: Some(true),
 861                        dynamic_registration: Some(true),
 862                        ..TextDocumentSyncClientCapabilities::default()
 863                    }),
 864                    code_lens: Some(CodeLensClientCapabilities {
 865                        dynamic_registration: Some(true),
 866                    }),
 867                    document_symbol: Some(DocumentSymbolClientCapabilities {
 868                        hierarchical_document_symbol_support: Some(true),
 869                        dynamic_registration: Some(true),
 870                        ..DocumentSymbolClientCapabilities::default()
 871                    }),
 872                    diagnostic: Some(DiagnosticClientCapabilities {
 873                        dynamic_registration: Some(true),
 874                        related_document_support: Some(true),
 875                    })
 876                    .filter(|_| pull_diagnostics),
 877                    color_provider: Some(DocumentColorClientCapabilities {
 878                        dynamic_registration: Some(true),
 879                    }),
 880                    ..TextDocumentClientCapabilities::default()
 881                }),
 882                experimental: Some(json!({
 883                    "serverStatusNotification": true,
 884                    "localDocs": true,
 885                })),
 886                window: Some(WindowClientCapabilities {
 887                    work_done_progress: Some(true),
 888                    show_message: Some(ShowMessageRequestClientCapabilities {
 889                        message_action_item: None,
 890                    }),
 891                    ..WindowClientCapabilities::default()
 892                }),
 893            },
 894            trace: None,
 895            workspace_folders: Some(workspace_folders),
 896            client_info: release_channel::ReleaseChannel::try_global(cx).map(|release_channel| {
 897                ClientInfo {
 898                    name: release_channel.display_name().to_string(),
 899                    version: Some(release_channel::AppVersion::global(cx).to_string()),
 900                }
 901            }),
 902            locale: None,
 903            ..InitializeParams::default()
 904        }
 905    }
 906
 907    /// Initializes a language server by sending the `Initialize` request.
 908    /// Note that `options` is used directly to construct [`InitializeParams`], which is why it is owned.
 909    ///
 910    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#initialize)
 911    pub fn initialize(
 912        mut self,
 913        params: InitializeParams,
 914        configuration: Arc<DidChangeConfigurationParams>,
 915        cx: &App,
 916    ) -> Task<Result<Arc<Self>>> {
 917        cx.background_spawn(async move {
 918            let response = self
 919                .request::<request::Initialize>(params)
 920                .await
 921                .into_response()
 922                .with_context(|| {
 923                    format!(
 924                        "initializing server {}, id {}",
 925                        self.name(),
 926                        self.server_id()
 927                    )
 928                })?;
 929            if let Some(info) = response.server_info {
 930                self.process_name = info.name.into();
 931            }
 932            self.capabilities = RwLock::new(response.capabilities);
 933            self.configuration = configuration;
 934
 935            self.notify::<notification::Initialized>(InitializedParams {})?;
 936            Ok(Arc::new(self))
 937        })
 938    }
 939
 940    /// Sends a shutdown request to the language server process and prepares the [`LanguageServer`] to be dropped.
 941    pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>> + use<>> {
 942        if let Some(tasks) = self.io_tasks.lock().take() {
 943            let response_handlers = self.response_handlers.clone();
 944            let next_id = AtomicI32::new(self.next_id.load(SeqCst));
 945            let outbound_tx = self.outbound_tx.clone();
 946            let executor = self.executor.clone();
 947            let notification_serializers = self.notification_tx.clone();
 948            let mut output_done = self.output_done_rx.lock().take().unwrap();
 949            let shutdown_request = Self::request_internal::<request::Shutdown>(
 950                &next_id,
 951                &response_handlers,
 952                &outbound_tx,
 953                &notification_serializers,
 954                &executor,
 955                (),
 956            );
 957
 958            let server = self.server.clone();
 959            let name = self.name.clone();
 960            let server_id = self.server_id;
 961            let mut timer = self.executor.timer(SERVER_SHUTDOWN_TIMEOUT).fuse();
 962            Some(async move {
 963                log::debug!("language server shutdown started");
 964
 965                select! {
 966                    request_result = shutdown_request.fuse() => {
 967                        match request_result {
 968                            ConnectionResult::Timeout => {
 969                                log::warn!("timeout waiting for language server {name} (id {server_id}) to shutdown");
 970                            },
 971                            ConnectionResult::ConnectionReset => {
 972                                log::warn!("language server {name} (id {server_id}) closed the shutdown request connection");
 973                            },
 974                            ConnectionResult::Result(Err(e)) => {
 975                                log::error!("Shutdown request failure, server {name} (id {server_id}): {e:#}");
 976                            },
 977                            ConnectionResult::Result(Ok(())) => {}
 978                        }
 979                    }
 980
 981                    _ = timer => {
 982                        log::info!("timeout waiting for language server {name} (id {server_id}) to shutdown");
 983                    },
 984                }
 985
 986                response_handlers.lock().take();
 987                Self::notify_internal::<notification::Exit>(&notification_serializers, ()).ok();
 988                notification_serializers.close();
 989                output_done.recv().await;
 990                server.lock().take().map(|mut child| child.kill());
 991                drop(tasks);
 992                log::debug!("language server shutdown finished");
 993                Some(())
 994            })
 995        } else {
 996            None
 997        }
 998    }
 999
1000    /// Register a handler to handle incoming LSP notifications.
1001    ///
1002    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
1003    #[must_use]
1004    pub fn on_notification<T, F>(&self, f: F) -> Subscription
1005    where
1006        T: notification::Notification,
1007        F: 'static + Send + FnMut(T::Params, &mut AsyncApp),
1008    {
1009        self.on_custom_notification(T::METHOD, f)
1010    }
1011
1012    /// Register a handler to handle incoming LSP requests.
1013    ///
1014    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
1015    #[must_use]
1016    pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
1017    where
1018        T: request::Request,
1019        T::Params: 'static + Send,
1020        F: 'static + FnMut(T::Params, &mut AsyncApp) -> Fut + Send,
1021        Fut: 'static + Future<Output = Result<T::Result>>,
1022    {
1023        self.on_custom_request(T::METHOD, f)
1024    }
1025
1026    /// Registers a handler to inspect all language server process stdio.
1027    #[must_use]
1028    pub fn on_io<F>(&self, f: F) -> Subscription
1029    where
1030        F: 'static + Send + FnMut(IoKind, &str),
1031    {
1032        let id = self.next_id.fetch_add(1, SeqCst);
1033        self.io_handlers.lock().insert(id, Box::new(f));
1034        Subscription::Io {
1035            id,
1036            io_handlers: Some(Arc::downgrade(&self.io_handlers)),
1037        }
1038    }
1039
1040    /// Removes a request handler registers via [`Self::on_request`].
1041    pub fn remove_request_handler<T: request::Request>(&self) {
1042        self.notification_handlers.lock().remove(T::METHOD);
1043    }
1044
1045    /// Removes a notification handler registers via [`Self::on_notification`].
1046    pub fn remove_notification_handler<T: notification::Notification>(&self) {
1047        self.notification_handlers.lock().remove(T::METHOD);
1048    }
1049
1050    /// Checks if a notification handler has been registered via [`Self::on_notification`].
1051    pub fn has_notification_handler<T: notification::Notification>(&self) -> bool {
1052        self.notification_handlers.lock().contains_key(T::METHOD)
1053    }
1054
1055    #[must_use]
1056    fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
1057    where
1058        F: 'static + FnMut(Params, &mut AsyncApp) + Send,
1059        Params: DeserializeOwned,
1060    {
1061        let prev_handler = self.notification_handlers.lock().insert(
1062            method,
1063            Box::new(move |_, params, cx| {
1064                if let Some(params) = serde_json::from_value(params).log_err() {
1065                    f(params, cx);
1066                }
1067            }),
1068        );
1069        assert!(
1070            prev_handler.is_none(),
1071            "registered multiple handlers for the same LSP method"
1072        );
1073        Subscription::Notification {
1074            method,
1075            notification_handlers: Some(self.notification_handlers.clone()),
1076        }
1077    }
1078
1079    #[must_use]
1080    fn on_custom_request<Params, Res, Fut, F>(&self, method: &'static str, mut f: F) -> Subscription
1081    where
1082        F: 'static + FnMut(Params, &mut AsyncApp) -> Fut + Send,
1083        Fut: 'static + Future<Output = Result<Res>>,
1084        Params: DeserializeOwned + Send + 'static,
1085        Res: Serialize,
1086    {
1087        let outbound_tx = self.outbound_tx.clone();
1088        let prev_handler = self.notification_handlers.lock().insert(
1089            method,
1090            Box::new(move |id, params, cx| {
1091                if let Some(id) = id {
1092                    match serde_json::from_value(params) {
1093                        Ok(params) => {
1094                            let response = f(params, cx);
1095                            cx.foreground_executor()
1096                                .spawn({
1097                                    let outbound_tx = outbound_tx.clone();
1098                                    async move {
1099                                        let response = match response.await {
1100                                            Ok(result) => Response {
1101                                                jsonrpc: JSON_RPC_VERSION,
1102                                                id,
1103                                                value: LspResult::Ok(Some(result)),
1104                                            },
1105                                            Err(error) => Response {
1106                                                jsonrpc: JSON_RPC_VERSION,
1107                                                id,
1108                                                value: LspResult::Error(Some(Error {
1109                                                    code: lsp_types::error_codes::REQUEST_FAILED,
1110                                                    message: error.to_string(),
1111                                                    data: None,
1112                                                })),
1113                                            },
1114                                        };
1115                                        if let Some(response) =
1116                                            serde_json::to_string(&response).log_err()
1117                                        {
1118                                            outbound_tx.try_send(response).ok();
1119                                        }
1120                                    }
1121                                })
1122                                .detach();
1123                        }
1124
1125                        Err(error) => {
1126                            log::error!("error deserializing {} request: {:?}", method, error);
1127                            let response = AnyResponse {
1128                                jsonrpc: JSON_RPC_VERSION,
1129                                id,
1130                                result: None,
1131                                error: Some(Error {
1132                                    code: -32700, // Parse error
1133                                    message: error.to_string(),
1134                                    data: None,
1135                                }),
1136                            };
1137                            if let Some(response) = serde_json::to_string(&response).log_err() {
1138                                outbound_tx.try_send(response).ok();
1139                            }
1140                        }
1141                    }
1142                }
1143            }),
1144        );
1145        assert!(
1146            prev_handler.is_none(),
1147            "registered multiple handlers for the same LSP method"
1148        );
1149        Subscription::Notification {
1150            method,
1151            notification_handlers: Some(self.notification_handlers.clone()),
1152        }
1153    }
1154
1155    /// Get the name of the running language server.
1156    pub fn name(&self) -> LanguageServerName {
1157        self.name.clone()
1158    }
1159
1160    pub fn process_name(&self) -> &str {
1161        &self.process_name
1162    }
1163
1164    /// Get the reported capabilities of the running language server.
1165    pub fn capabilities(&self) -> ServerCapabilities {
1166        self.capabilities.read().clone()
1167    }
1168
1169    /// Get the reported capabilities of the running language server and
1170    /// what we know on the client/adapter-side of its capabilities.
1171    pub fn adapter_server_capabilities(&self) -> AdapterServerCapabilities {
1172        AdapterServerCapabilities {
1173            server_capabilities: self.capabilities(),
1174            code_action_kinds: self.code_action_kinds(),
1175        }
1176    }
1177
1178    pub fn update_capabilities(&self, update: impl FnOnce(&mut ServerCapabilities)) {
1179        update(self.capabilities.write().deref_mut());
1180    }
1181
1182    pub fn configuration(&self) -> &Value {
1183        &self.configuration.settings
1184    }
1185
1186    /// Get the id of the running language server.
1187    pub fn server_id(&self) -> LanguageServerId {
1188        self.server_id
1189    }
1190
1191    /// Language server's binary information.
1192    pub fn binary(&self) -> &LanguageServerBinary {
1193        &self.binary
1194    }
1195
1196    /// Sends a RPC request to the language server.
1197    ///
1198    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
1199    pub fn request<T: request::Request>(
1200        &self,
1201        params: T::Params,
1202    ) -> impl LspRequestFuture<T::Result> + use<T>
1203    where
1204        T::Result: 'static + Send,
1205    {
1206        Self::request_internal::<T>(
1207            &self.next_id,
1208            &self.response_handlers,
1209            &self.outbound_tx,
1210            &self.notification_tx,
1211            &self.executor,
1212            params,
1213        )
1214    }
1215
1216    /// Sends a RPC request to the language server, with a custom timer, a future which when becoming
1217    /// ready causes the request to be timed out with the future's output message.
1218    ///
1219    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
1220    pub fn request_with_timer<T: request::Request, U: Future<Output = String>>(
1221        &self,
1222        params: T::Params,
1223        timer: U,
1224    ) -> impl LspRequestFuture<T::Result> + use<T, U>
1225    where
1226        T::Result: 'static + Send,
1227    {
1228        Self::request_internal_with_timer::<T, U>(
1229            &self.next_id,
1230            &self.response_handlers,
1231            &self.outbound_tx,
1232            &self.notification_tx,
1233            &self.executor,
1234            timer,
1235            params,
1236        )
1237    }
1238
1239    fn request_internal_with_timer<T, U>(
1240        next_id: &AtomicI32,
1241        response_handlers: &Mutex<Option<HashMap<RequestId, ResponseHandler>>>,
1242        outbound_tx: &channel::Sender<String>,
1243        notification_serializers: &channel::Sender<NotificationSerializer>,
1244        executor: &BackgroundExecutor,
1245        timer: U,
1246        params: T::Params,
1247    ) -> impl LspRequestFuture<T::Result> + use<T, U>
1248    where
1249        T::Result: 'static + Send,
1250        T: request::Request,
1251        U: Future<Output = String>,
1252    {
1253        let id = next_id.fetch_add(1, SeqCst);
1254        let message = serde_json::to_string(&Request {
1255            jsonrpc: JSON_RPC_VERSION,
1256            id: RequestId::Int(id),
1257            method: T::METHOD,
1258            params,
1259        })
1260        .unwrap();
1261
1262        let (tx, rx) = oneshot::channel();
1263        let handle_response = response_handlers
1264            .lock()
1265            .as_mut()
1266            .context("server shut down")
1267            .map(|handlers| {
1268                let executor = executor.clone();
1269                handlers.insert(
1270                    RequestId::Int(id),
1271                    Box::new(move |result| {
1272                        executor
1273                            .spawn(async move {
1274                                let response = match result {
1275                                    Ok(response) => match serde_json::from_str(&response) {
1276                                        Ok(deserialized) => Ok(deserialized),
1277                                        Err(error) => {
1278                                            log::error!("failed to deserialize response from language server: {}. response from language server: {:?}", error, response);
1279                                            Err(error).context("failed to deserialize response")
1280                                        }
1281                                    }
1282                                    Err(error) => Err(anyhow!("{}", error.message)),
1283                                };
1284                                _ = tx.send(response);
1285                            })
1286                            .detach();
1287                    }),
1288                );
1289            });
1290
1291        let send = outbound_tx
1292            .try_send(message)
1293            .context("failed to write to language server's stdin");
1294
1295        let notification_serializers = notification_serializers.downgrade();
1296        let started = Instant::now();
1297        LspRequest::new(id, async move {
1298            if let Err(e) = handle_response {
1299                return ConnectionResult::Result(Err(e));
1300            }
1301            if let Err(e) = send {
1302                return ConnectionResult::Result(Err(e));
1303            }
1304
1305            let cancel_on_drop = util::defer(move || {
1306                if let Some(notification_serializers) = notification_serializers.upgrade() {
1307                    Self::notify_internal::<notification::Cancel>(
1308                        &notification_serializers,
1309                        CancelParams {
1310                            id: NumberOrString::Number(id),
1311                        },
1312                    )
1313                    .ok();
1314                }
1315            });
1316
1317            let method = T::METHOD;
1318            select! {
1319                response = rx.fuse() => {
1320                    let elapsed = started.elapsed();
1321                    log::trace!("Took {elapsed:?} to receive response to {method:?} id {id}");
1322                    cancel_on_drop.abort();
1323                    match response {
1324                        Ok(response_result) => ConnectionResult::Result(response_result),
1325                        Err(Canceled) => {
1326                            log::error!("Server reset connection for a request {method:?} id {id}");
1327                            ConnectionResult::ConnectionReset
1328                        },
1329                    }
1330                }
1331
1332                message = timer.fuse() => {
1333                    log::error!("Cancelled LSP request task for {method:?} id {id} {message}");
1334                    ConnectionResult::Timeout
1335                }
1336            }
1337        })
1338    }
1339
1340    fn request_internal<T>(
1341        next_id: &AtomicI32,
1342        response_handlers: &Mutex<Option<HashMap<RequestId, ResponseHandler>>>,
1343        outbound_tx: &channel::Sender<String>,
1344        notification_serializers: &channel::Sender<NotificationSerializer>,
1345        executor: &BackgroundExecutor,
1346        params: T::Params,
1347    ) -> impl LspRequestFuture<T::Result> + use<T>
1348    where
1349        T::Result: 'static + Send,
1350        T: request::Request,
1351    {
1352        Self::request_internal_with_timer::<T, _>(
1353            next_id,
1354            response_handlers,
1355            outbound_tx,
1356            notification_serializers,
1357            executor,
1358            Self::default_request_timer(executor.clone()),
1359            params,
1360        )
1361    }
1362
1363    pub fn default_request_timer(executor: BackgroundExecutor) -> impl Future<Output = String> {
1364        executor
1365            .timer(LSP_REQUEST_TIMEOUT)
1366            .map(|_| format!("which took over {LSP_REQUEST_TIMEOUT:?}"))
1367    }
1368
1369    /// Sends a RPC notification to the language server.
1370    ///
1371    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
1372    pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
1373        let outbound = self.notification_tx.clone();
1374        Self::notify_internal::<T>(&outbound, params)
1375    }
1376
1377    fn notify_internal<T: notification::Notification>(
1378        outbound_tx: &channel::Sender<NotificationSerializer>,
1379        params: T::Params,
1380    ) -> Result<()> {
1381        let serializer = NotificationSerializer(Box::new(move || {
1382            serde_json::to_string(&Notification {
1383                jsonrpc: JSON_RPC_VERSION,
1384                method: T::METHOD,
1385                params,
1386            })
1387            .unwrap()
1388        }));
1389
1390        outbound_tx.send_blocking(serializer)?;
1391        Ok(())
1392    }
1393
1394    /// Add new workspace folder to the list.
1395    pub fn add_workspace_folder(&self, uri: Uri) {
1396        if self
1397            .capabilities()
1398            .workspace
1399            .and_then(|ws| {
1400                ws.workspace_folders.and_then(|folders| {
1401                    folders
1402                        .change_notifications
1403                        .map(|caps| matches!(caps, OneOf::Left(false)))
1404                })
1405            })
1406            .unwrap_or(true)
1407        {
1408            return;
1409        }
1410
1411        let Some(workspace_folders) = self.workspace_folders.as_ref() else {
1412            return;
1413        };
1414        let is_new_folder = workspace_folders.lock().insert(uri.clone());
1415        if is_new_folder {
1416            let params = DidChangeWorkspaceFoldersParams {
1417                event: WorkspaceFoldersChangeEvent {
1418                    added: vec![WorkspaceFolder {
1419                        uri,
1420                        name: String::default(),
1421                    }],
1422                    removed: vec![],
1423                },
1424            };
1425            self.notify::<DidChangeWorkspaceFolders>(params).ok();
1426        }
1427    }
1428
1429    /// Remove existing workspace folder from the list.
1430    pub fn remove_workspace_folder(&self, uri: Uri) {
1431        if self
1432            .capabilities()
1433            .workspace
1434            .and_then(|ws| {
1435                ws.workspace_folders.and_then(|folders| {
1436                    folders
1437                        .change_notifications
1438                        .map(|caps| !matches!(caps, OneOf::Left(false)))
1439                })
1440            })
1441            .unwrap_or(true)
1442        {
1443            return;
1444        }
1445        let Some(workspace_folders) = self.workspace_folders.as_ref() else {
1446            return;
1447        };
1448        let was_removed = workspace_folders.lock().remove(&uri);
1449        if was_removed {
1450            let params = DidChangeWorkspaceFoldersParams {
1451                event: WorkspaceFoldersChangeEvent {
1452                    added: vec![],
1453                    removed: vec![WorkspaceFolder {
1454                        uri,
1455                        name: String::default(),
1456                    }],
1457                },
1458            };
1459            self.notify::<DidChangeWorkspaceFolders>(params).ok();
1460        }
1461    }
1462    pub fn set_workspace_folders(&self, folders: BTreeSet<Uri>) {
1463        let Some(workspace_folders) = self.workspace_folders.as_ref() else {
1464            return;
1465        };
1466        let mut workspace_folders = workspace_folders.lock();
1467
1468        let old_workspace_folders = std::mem::take(&mut *workspace_folders);
1469        let added: Vec<_> = folders
1470            .difference(&old_workspace_folders)
1471            .map(|uri| WorkspaceFolder {
1472                uri: uri.clone(),
1473                name: String::default(),
1474            })
1475            .collect();
1476
1477        let removed: Vec<_> = old_workspace_folders
1478            .difference(&folders)
1479            .map(|uri| WorkspaceFolder {
1480                uri: uri.clone(),
1481                name: String::default(),
1482            })
1483            .collect();
1484        *workspace_folders = folders;
1485        let should_notify = !added.is_empty() || !removed.is_empty();
1486        if should_notify {
1487            drop(workspace_folders);
1488            let params = DidChangeWorkspaceFoldersParams {
1489                event: WorkspaceFoldersChangeEvent { added, removed },
1490            };
1491            self.notify::<DidChangeWorkspaceFolders>(params).ok();
1492        }
1493    }
1494
1495    pub fn workspace_folders(&self) -> BTreeSet<Uri> {
1496        self.workspace_folders.as_ref().map_or_else(
1497            || BTreeSet::from_iter([self.root_uri.clone()]),
1498            |folders| folders.lock().clone(),
1499        )
1500    }
1501
1502    pub fn register_buffer(
1503        &self,
1504        uri: Uri,
1505        language_id: String,
1506        version: i32,
1507        initial_text: String,
1508    ) {
1509        self.notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1510            text_document: TextDocumentItem::new(uri, language_id, version, initial_text),
1511        })
1512        .ok();
1513    }
1514
1515    pub fn unregister_buffer(&self, uri: Uri) {
1516        self.notify::<notification::DidCloseTextDocument>(DidCloseTextDocumentParams {
1517            text_document: TextDocumentIdentifier::new(uri),
1518        })
1519        .ok();
1520    }
1521}
1522
1523impl Drop for LanguageServer {
1524    fn drop(&mut self) {
1525        if let Some(shutdown) = self.shutdown() {
1526            self.executor.spawn(shutdown).detach();
1527        }
1528    }
1529}
1530
1531impl Subscription {
1532    /// Detaching a subscription handle prevents it from unsubscribing on drop.
1533    pub fn detach(&mut self) {
1534        match self {
1535            Subscription::Notification {
1536                notification_handlers,
1537                ..
1538            } => *notification_handlers = None,
1539            Subscription::Io { io_handlers, .. } => *io_handlers = None,
1540        }
1541    }
1542}
1543
1544impl fmt::Display for LanguageServerId {
1545    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1546        self.0.fmt(f)
1547    }
1548}
1549
1550impl fmt::Debug for LanguageServer {
1551    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1552        f.debug_struct("LanguageServer")
1553            .field("id", &self.server_id.0)
1554            .field("name", &self.name)
1555            .finish_non_exhaustive()
1556    }
1557}
1558
1559impl fmt::Debug for LanguageServerBinary {
1560    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1561        let mut debug = f.debug_struct("LanguageServerBinary");
1562        debug.field("path", &self.path);
1563        debug.field("arguments", &self.arguments);
1564
1565        if let Some(env) = &self.env {
1566            let redacted_env: BTreeMap<String, String> = env
1567                .iter()
1568                .map(|(key, value)| {
1569                    let redacted_value = if redact::should_redact(key) {
1570                        "REDACTED".to_string()
1571                    } else {
1572                        value.clone()
1573                    };
1574                    (key.clone(), redacted_value)
1575                })
1576                .collect();
1577            debug.field("env", &Some(redacted_env));
1578        } else {
1579            debug.field("env", &self.env);
1580        }
1581
1582        debug.finish()
1583    }
1584}
1585
1586impl Drop for Subscription {
1587    fn drop(&mut self) {
1588        match self {
1589            Subscription::Notification {
1590                method,
1591                notification_handlers,
1592            } => {
1593                if let Some(handlers) = notification_handlers {
1594                    handlers.lock().remove(method);
1595                }
1596            }
1597            Subscription::Io { id, io_handlers } => {
1598                if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
1599                    io_handlers.lock().remove(id);
1600                }
1601            }
1602        }
1603    }
1604}
1605
1606/// Mock language server for use in tests.
1607#[cfg(any(test, feature = "test-support"))]
1608#[derive(Clone)]
1609pub struct FakeLanguageServer {
1610    pub binary: LanguageServerBinary,
1611    pub server: Arc<LanguageServer>,
1612    notifications_rx: channel::Receiver<(String, String)>,
1613}
1614
1615#[cfg(any(test, feature = "test-support"))]
1616impl FakeLanguageServer {
1617    /// Construct a fake language server.
1618    pub fn new(
1619        server_id: LanguageServerId,
1620        binary: LanguageServerBinary,
1621        name: String,
1622        capabilities: ServerCapabilities,
1623        cx: &mut AsyncApp,
1624    ) -> (LanguageServer, FakeLanguageServer) {
1625        let (stdin_writer, stdin_reader) = async_pipe::pipe();
1626        let (stdout_writer, stdout_reader) = async_pipe::pipe();
1627        let (notifications_tx, notifications_rx) = channel::unbounded();
1628
1629        let server_name = LanguageServerName(name.clone().into());
1630        let process_name = Arc::from(name.as_str());
1631        let root = Self::root_path();
1632        let workspace_folders: Arc<Mutex<BTreeSet<Uri>>> = Default::default();
1633        let mut server = LanguageServer::new_internal(
1634            server_id,
1635            server_name.clone(),
1636            stdin_writer,
1637            stdout_reader,
1638            None::<async_pipe::PipeReader>,
1639            Arc::new(Mutex::new(None)),
1640            None,
1641            None,
1642            binary.clone(),
1643            root,
1644            Some(workspace_folders.clone()),
1645            cx,
1646            |_| false,
1647        );
1648        server.process_name = process_name;
1649        let fake = FakeLanguageServer {
1650            binary: binary.clone(),
1651            server: Arc::new({
1652                let mut server = LanguageServer::new_internal(
1653                    server_id,
1654                    server_name,
1655                    stdout_writer,
1656                    stdin_reader,
1657                    None::<async_pipe::PipeReader>,
1658                    Arc::new(Mutex::new(None)),
1659                    None,
1660                    None,
1661                    binary,
1662                    Self::root_path(),
1663                    Some(workspace_folders),
1664                    cx,
1665                    move |msg| {
1666                        notifications_tx
1667                            .try_send((
1668                                msg.method.to_string(),
1669                                msg.params.as_ref().unwrap_or(&Value::Null).to_string(),
1670                            ))
1671                            .ok();
1672                        true
1673                    },
1674                );
1675                server.process_name = name.as_str().into();
1676                server
1677            }),
1678            notifications_rx,
1679        };
1680        fake.set_request_handler::<request::Initialize, _, _>({
1681            let capabilities = capabilities;
1682            move |_, _| {
1683                let capabilities = capabilities.clone();
1684                let name = name.clone();
1685                async move {
1686                    Ok(InitializeResult {
1687                        capabilities,
1688                        server_info: Some(ServerInfo {
1689                            name,
1690                            ..Default::default()
1691                        }),
1692                    })
1693                }
1694            }
1695        });
1696
1697        fake.set_request_handler::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1698
1699        (server, fake)
1700    }
1701    #[cfg(target_os = "windows")]
1702    fn root_path() -> Uri {
1703        Uri::from_file_path("C:/").unwrap()
1704    }
1705
1706    #[cfg(not(target_os = "windows"))]
1707    fn root_path() -> Uri {
1708        Uri::from_file_path("/").unwrap()
1709    }
1710}
1711
1712#[cfg(any(test, feature = "test-support"))]
1713impl LanguageServer {
1714    pub fn full_capabilities() -> ServerCapabilities {
1715        ServerCapabilities {
1716            document_highlight_provider: Some(OneOf::Left(true)),
1717            code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
1718            document_formatting_provider: Some(OneOf::Left(true)),
1719            document_range_formatting_provider: Some(OneOf::Left(true)),
1720            definition_provider: Some(OneOf::Left(true)),
1721            workspace_symbol_provider: Some(OneOf::Left(true)),
1722            implementation_provider: Some(ImplementationProviderCapability::Simple(true)),
1723            type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
1724            ..ServerCapabilities::default()
1725        }
1726    }
1727}
1728
1729#[cfg(any(test, feature = "test-support"))]
1730impl FakeLanguageServer {
1731    /// See [`LanguageServer::notify`].
1732    pub fn notify<T: notification::Notification>(&self, params: T::Params) {
1733        self.server.notify::<T>(params).ok();
1734    }
1735
1736    /// See [`LanguageServer::request`].
1737    pub async fn request<T>(&self, params: T::Params) -> ConnectionResult<T::Result>
1738    where
1739        T: request::Request,
1740        T::Result: 'static + Send,
1741    {
1742        self.server.executor.start_waiting();
1743        self.server.request::<T>(params).await
1744    }
1745
1746    /// Attempts [`Self::try_receive_notification`], unwrapping if it has not received the specified type yet.
1747    pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
1748        self.server.executor.start_waiting();
1749        self.try_receive_notification::<T>().await.unwrap()
1750    }
1751
1752    /// Consumes the notification channel until it finds a notification for the specified type.
1753    pub async fn try_receive_notification<T: notification::Notification>(
1754        &mut self,
1755    ) -> Option<T::Params> {
1756        loop {
1757            let (method, params) = self.notifications_rx.recv().await.ok()?;
1758            if method == T::METHOD {
1759                return Some(serde_json::from_str::<T::Params>(&params).unwrap());
1760            } else {
1761                log::info!("skipping message in fake language server {:?}", params);
1762            }
1763        }
1764    }
1765
1766    /// Registers a handler for a specific kind of request. Removes any existing handler for specified request type.
1767    pub fn set_request_handler<T, F, Fut>(
1768        &self,
1769        mut handler: F,
1770    ) -> futures::channel::mpsc::UnboundedReceiver<()>
1771    where
1772        T: 'static + request::Request,
1773        T::Params: 'static + Send,
1774        F: 'static + Send + FnMut(T::Params, gpui::AsyncApp) -> Fut,
1775        Fut: 'static + Future<Output = Result<T::Result>>,
1776    {
1777        let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
1778        self.server.remove_request_handler::<T>();
1779        self.server
1780            .on_request::<T, _, _>(move |params, cx| {
1781                let result = handler(params, cx.clone());
1782                let responded_tx = responded_tx.clone();
1783                let executor = cx.background_executor().clone();
1784                async move {
1785                    executor.simulate_random_delay().await;
1786                    let result = result.await;
1787                    responded_tx.unbounded_send(()).ok();
1788                    result
1789                }
1790            })
1791            .detach();
1792        responded_rx
1793    }
1794
1795    /// Registers a handler for a specific kind of notification. Removes any existing handler for specified notification type.
1796    pub fn handle_notification<T, F>(
1797        &self,
1798        mut handler: F,
1799    ) -> futures::channel::mpsc::UnboundedReceiver<()>
1800    where
1801        T: 'static + notification::Notification,
1802        T::Params: 'static + Send,
1803        F: 'static + Send + FnMut(T::Params, gpui::AsyncApp),
1804    {
1805        let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
1806        self.server.remove_notification_handler::<T>();
1807        self.server
1808            .on_notification::<T, _>(move |params, cx| {
1809                handler(params, cx.clone());
1810                handled_tx.unbounded_send(()).ok();
1811            })
1812            .detach();
1813        handled_rx
1814    }
1815
1816    /// Removes any existing handler for specified notification type.
1817    pub fn remove_request_handler<T>(&mut self)
1818    where
1819        T: 'static + request::Request,
1820    {
1821        self.server.remove_request_handler::<T>();
1822    }
1823
1824    /// Simulate that the server has started work and notifies about its progress with the specified token.
1825    pub async fn start_progress(&self, token: impl Into<String>) {
1826        self.start_progress_with(token, Default::default()).await
1827    }
1828
1829    pub async fn start_progress_with(
1830        &self,
1831        token: impl Into<String>,
1832        progress: WorkDoneProgressBegin,
1833    ) {
1834        let token = token.into();
1835        self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
1836            token: NumberOrString::String(token.clone()),
1837        })
1838        .await
1839        .into_response()
1840        .unwrap();
1841        self.notify::<notification::Progress>(ProgressParams {
1842            token: NumberOrString::String(token),
1843            value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(progress)),
1844        });
1845    }
1846
1847    /// Simulate that the server has completed work and notifies about that with the specified token.
1848    pub fn end_progress(&self, token: impl Into<String>) {
1849        self.notify::<notification::Progress>(ProgressParams {
1850            token: NumberOrString::String(token.into()),
1851            value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1852        });
1853    }
1854}
1855
1856#[cfg(test)]
1857mod tests {
1858    use super::*;
1859    use gpui::TestAppContext;
1860    use std::str::FromStr;
1861
1862    #[ctor::ctor]
1863    fn init_logger() {
1864        zlog::init_test();
1865    }
1866
1867    #[gpui::test]
1868    async fn test_fake(cx: &mut TestAppContext) {
1869        cx.update(|cx| {
1870            release_channel::init(semver::Version::new(0, 0, 0), cx);
1871        });
1872        let (server, mut fake) = FakeLanguageServer::new(
1873            LanguageServerId(0),
1874            LanguageServerBinary {
1875                path: "path/to/language-server".into(),
1876                arguments: vec![],
1877                env: None,
1878            },
1879            "the-lsp".to_string(),
1880            Default::default(),
1881            &mut cx.to_async(),
1882        );
1883
1884        let (message_tx, message_rx) = channel::unbounded();
1885        let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1886        server
1887            .on_notification::<notification::ShowMessage, _>(move |params, _| {
1888                message_tx.try_send(params).unwrap()
1889            })
1890            .detach();
1891        server
1892            .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1893                diagnostics_tx.try_send(params).unwrap()
1894            })
1895            .detach();
1896
1897        let server = cx
1898            .update(|cx| {
1899                let params = server.default_initialize_params(false, cx);
1900                let configuration = DidChangeConfigurationParams {
1901                    settings: Default::default(),
1902                };
1903                server.initialize(params, configuration.into(), cx)
1904            })
1905            .await
1906            .unwrap();
1907        server
1908            .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1909                text_document: TextDocumentItem::new(
1910                    Uri::from_str("file://a/b").unwrap(),
1911                    "rust".to_string(),
1912                    0,
1913                    "".to_string(),
1914                ),
1915            })
1916            .unwrap();
1917        assert_eq!(
1918            fake.receive_notification::<notification::DidOpenTextDocument>()
1919                .await
1920                .text_document
1921                .uri
1922                .as_str(),
1923            "file://a/b"
1924        );
1925
1926        fake.notify::<notification::ShowMessage>(ShowMessageParams {
1927            typ: MessageType::ERROR,
1928            message: "ok".to_string(),
1929        });
1930        fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1931            uri: Uri::from_str("file://b/c").unwrap(),
1932            version: Some(5),
1933            diagnostics: vec![],
1934        });
1935        assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1936        assert_eq!(
1937            diagnostics_rx.recv().await.unwrap().uri.as_str(),
1938            "file://b/c"
1939        );
1940
1941        fake.set_request_handler::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1942
1943        drop(server);
1944        cx.run_until_parked();
1945        fake.receive_notification::<notification::Exit>().await;
1946    }
1947
1948    #[gpui::test]
1949    fn test_deserialize_string_digit_id() {
1950        let json = r#"{"jsonrpc":"2.0","id":"2","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1951        let notification = serde_json::from_str::<NotificationOrRequest>(json)
1952            .expect("message with string id should be parsed");
1953        let expected_id = RequestId::Str("2".to_string());
1954        assert_eq!(notification.id, Some(expected_id));
1955    }
1956
1957    #[gpui::test]
1958    fn test_deserialize_string_id() {
1959        let json = r#"{"jsonrpc":"2.0","id":"anythingAtAll","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1960        let notification = serde_json::from_str::<NotificationOrRequest>(json)
1961            .expect("message with string id should be parsed");
1962        let expected_id = RequestId::Str("anythingAtAll".to_string());
1963        assert_eq!(notification.id, Some(expected_id));
1964    }
1965
1966    #[gpui::test]
1967    fn test_deserialize_int_id() {
1968        let json = r#"{"jsonrpc":"2.0","id":2,"method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1969        let notification = serde_json::from_str::<NotificationOrRequest>(json)
1970            .expect("message with string id should be parsed");
1971        let expected_id = RequestId::Int(2);
1972        assert_eq!(notification.id, Some(expected_id));
1973    }
1974
1975    #[test]
1976    fn test_serialize_has_no_nulls() {
1977        // Ensure we're not setting both result and error variants. (ticket #10595)
1978        let no_tag = Response::<u32> {
1979            jsonrpc: "",
1980            id: RequestId::Int(0),
1981            value: LspResult::Ok(None),
1982        };
1983        assert_eq!(
1984            serde_json::to_string(&no_tag).unwrap(),
1985            "{\"jsonrpc\":\"\",\"id\":0,\"result\":null}"
1986        );
1987        let no_tag = Response::<u32> {
1988            jsonrpc: "",
1989            id: RequestId::Int(0),
1990            value: LspResult::Error(None),
1991        };
1992        assert_eq!(
1993            serde_json::to_string(&no_tag).unwrap(),
1994            "{\"jsonrpc\":\"\",\"id\":0,\"error\":null}"
1995        );
1996    }
1997}