lsp.rs

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