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