lsp.rs

   1use log::warn;
   2pub use lsp_types::request::*;
   3pub use lsp_types::*;
   4
   5use anyhow::{anyhow, Context, Result};
   6use collections::HashMap;
   7use futures::{channel::oneshot, io::BufWriter, select, AsyncRead, AsyncWrite, Future, FutureExt};
   8use gpui::{AppContext, AsyncAppContext, BackgroundExecutor, Task};
   9use parking_lot::Mutex;
  10use postage::{barrier, prelude::Stream};
  11use serde::{de::DeserializeOwned, Deserialize, Serialize};
  12use serde_json::{json, value::RawValue, Value};
  13use smol::{
  14    channel,
  15    io::{AsyncBufReadExt, AsyncReadExt, AsyncWriteExt, BufReader},
  16    process::{self, Child},
  17};
  18
  19#[cfg(target_os = "windows")]
  20use smol::process::windows::CommandExt;
  21
  22use std::{
  23    ffi::OsString,
  24    fmt,
  25    io::Write,
  26    path::PathBuf,
  27    pin::Pin,
  28    str::{self, FromStr as _},
  29    sync::{
  30        atomic::{AtomicI32, Ordering::SeqCst},
  31        Arc, Weak,
  32    },
  33    task::Poll,
  34    time::{Duration, Instant},
  35};
  36use std::{path::Path, process::Stdio};
  37use util::{ResultExt, TryFutureExt};
  38
  39const HEADER_DELIMITER: &'static [u8; 4] = b"\r\n\r\n";
  40const JSON_RPC_VERSION: &str = "2.0";
  41const CONTENT_LEN_HEADER: &str = "Content-Length: ";
  42const LSP_REQUEST_TIMEOUT: Duration = Duration::from_secs(60 * 2);
  43const SERVER_SHUTDOWN_TIMEOUT: Duration = Duration::from_secs(5);
  44
  45type NotificationHandler = Box<dyn Send + FnMut(Option<RequestId>, &str, AsyncAppContext)>;
  46type ResponseHandler = Box<dyn Send + FnOnce(Result<String, Error>)>;
  47type IoHandler = Box<dyn Send + FnMut(IoKind, &str)>;
  48
  49/// Kind of language server stdio given to an IO handler.
  50#[derive(Debug, Clone, Copy)]
  51pub enum IoKind {
  52    StdOut,
  53    StdIn,
  54    StdErr,
  55}
  56
  57/// Represents a launchable language server. This can either be a standalone binary or the path
  58/// to a runtime with arguments to instruct it to launch the actual language server file.
  59#[derive(Debug, Clone, Deserialize)]
  60pub struct LanguageServerBinary {
  61    pub path: PathBuf,
  62    pub arguments: Vec<OsString>,
  63    pub env: Option<HashMap<String, String>>,
  64}
  65
  66/// A running language server process.
  67pub struct LanguageServer {
  68    server_id: LanguageServerId,
  69    next_id: AtomicI32,
  70    outbound_tx: channel::Sender<String>,
  71    name: Arc<str>,
  72    capabilities: ServerCapabilities,
  73    code_action_kinds: Option<Vec<CodeActionKind>>,
  74    notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
  75    response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
  76    io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
  77    executor: BackgroundExecutor,
  78    #[allow(clippy::type_complexity)]
  79    io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
  80    output_done_rx: Mutex<Option<barrier::Receiver>>,
  81    root_path: PathBuf,
  82    server: Arc<Mutex<Option<Child>>>,
  83}
  84
  85/// Identifies a running language server.
  86#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
  87#[repr(transparent)]
  88pub struct LanguageServerId(pub usize);
  89
  90/// Handle to a language server RPC activity subscription.
  91pub enum Subscription {
  92    Notification {
  93        method: &'static str,
  94        notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
  95    },
  96    Io {
  97        id: i32,
  98        io_handlers: Option<Weak<Mutex<HashMap<i32, IoHandler>>>>,
  99    },
 100}
 101
 102/// Language server protocol RPC request message ID.
 103///
 104/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 105#[derive(Debug, Clone, Eq, PartialEq, Hash, Serialize, Deserialize)]
 106#[serde(untagged)]
 107pub enum RequestId {
 108    Int(i32),
 109    Str(String),
 110}
 111
 112/// Language server protocol RPC request message.
 113///
 114/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 115#[derive(Serialize, Deserialize)]
 116pub struct Request<'a, T> {
 117    jsonrpc: &'static str,
 118    id: RequestId,
 119    method: &'a str,
 120    params: T,
 121}
 122
 123/// Language server protocol RPC request response message before it is deserialized into a concrete type.
 124#[derive(Serialize, Deserialize)]
 125struct AnyResponse<'a> {
 126    jsonrpc: &'a str,
 127    id: RequestId,
 128    #[serde(default)]
 129    error: Option<Error>,
 130    #[serde(borrow)]
 131    result: Option<&'a RawValue>,
 132}
 133
 134/// Language server protocol RPC request response message.
 135///
 136/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#responseMessage)
 137#[derive(Serialize)]
 138struct Response<T> {
 139    jsonrpc: &'static str,
 140    id: RequestId,
 141    #[serde(flatten)]
 142    value: LspResult<T>,
 143}
 144
 145#[derive(Serialize)]
 146#[serde(rename_all = "snake_case")]
 147enum LspResult<T> {
 148    #[serde(rename = "result")]
 149    Ok(Option<T>),
 150    Error(Option<Error>),
 151}
 152
 153/// Language server protocol RPC notification message.
 154///
 155/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
 156#[derive(Serialize, Deserialize)]
 157struct Notification<'a, T> {
 158    jsonrpc: &'static str,
 159    #[serde(borrow)]
 160    method: &'a str,
 161    params: T,
 162}
 163
 164/// Language server RPC notification message before it is deserialized into a concrete type.
 165#[derive(Debug, Clone, Deserialize)]
 166struct AnyNotification<'a> {
 167    #[serde(default)]
 168    id: Option<RequestId>,
 169    #[serde(borrow)]
 170    method: &'a str,
 171    #[serde(borrow, default)]
 172    params: Option<&'a RawValue>,
 173}
 174
 175#[derive(Debug, Serialize, Deserialize)]
 176struct Error {
 177    message: String,
 178}
 179
 180pub trait LspRequestFuture<O>: Future<Output = O> {
 181    fn id(&self) -> i32;
 182}
 183
 184struct LspRequest<F> {
 185    id: i32,
 186    request: F,
 187}
 188
 189impl<F> LspRequest<F> {
 190    pub fn new(id: i32, request: F) -> Self {
 191        Self { id, request }
 192    }
 193}
 194
 195impl<F: Future> Future for LspRequest<F> {
 196    type Output = F::Output;
 197
 198    fn poll(self: Pin<&mut Self>, cx: &mut std::task::Context<'_>) -> Poll<Self::Output> {
 199        // SAFETY: This is standard pin projection, we're pinned so our fields must be pinned.
 200        let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().request) };
 201        inner.poll(cx)
 202    }
 203}
 204
 205impl<F: Future> LspRequestFuture<F::Output> for LspRequest<F> {
 206    fn id(&self) -> i32 {
 207        self.id
 208    }
 209}
 210
 211/// Experimental: Informs the end user about the state of the server
 212///
 213/// [Rust Analyzer Specification](https://github.com/rust-lang/rust-analyzer/blob/master/docs/dev/lsp-extensions.md#server-status)
 214#[derive(Debug)]
 215pub enum ServerStatus {}
 216
 217/// Other(String) variant to handle unknown values due to this still being experimental
 218#[derive(Debug, PartialEq, Deserialize, Serialize, Clone)]
 219#[serde(rename_all = "camelCase")]
 220pub enum ServerHealthStatus {
 221    Ok,
 222    Warning,
 223    Error,
 224    Other(String),
 225}
 226
 227#[derive(Debug, PartialEq, Deserialize, Serialize, Clone)]
 228#[serde(rename_all = "camelCase")]
 229pub struct ServerStatusParams {
 230    pub health: ServerHealthStatus,
 231    pub message: Option<String>,
 232}
 233
 234impl lsp_types::notification::Notification for ServerStatus {
 235    type Params = ServerStatusParams;
 236    const METHOD: &'static str = "experimental/serverStatus";
 237}
 238
 239impl LanguageServer {
 240    /// Starts a language server process.
 241    pub fn new(
 242        stderr_capture: Arc<Mutex<Option<String>>>,
 243        server_id: LanguageServerId,
 244        binary: LanguageServerBinary,
 245        root_path: &Path,
 246        code_action_kinds: Option<Vec<CodeActionKind>>,
 247        cx: AsyncAppContext,
 248    ) -> Result<Self> {
 249        let working_dir = if root_path.is_dir() {
 250            root_path
 251        } else {
 252            root_path.parent().unwrap_or_else(|| Path::new("/"))
 253        };
 254
 255        log::info!(
 256            "starting language server. binary path: {:?}, working directory: {:?}, args: {:?}",
 257            binary.path,
 258            working_dir,
 259            &binary.arguments
 260        );
 261
 262        let mut command = process::Command::new(&binary.path);
 263        command
 264            .current_dir(working_dir)
 265            .args(&binary.arguments)
 266            .envs(binary.env.unwrap_or_default())
 267            .stdin(Stdio::piped())
 268            .stdout(Stdio::piped())
 269            .stderr(Stdio::piped())
 270            .kill_on_drop(true);
 271        #[cfg(windows)]
 272        command.creation_flags(windows::Win32::System::Threading::CREATE_NO_WINDOW.0);
 273        let mut server = command.spawn().with_context(|| {
 274            format!(
 275                "failed to spawn command. path: {:?}, working directory: {:?}, args: {:?}",
 276                binary.path, working_dir, &binary.arguments
 277            )
 278        })?;
 279
 280        let stdin = server.stdin.take().unwrap();
 281        let stdout = server.stdout.take().unwrap();
 282        let stderr = server.stderr.take().unwrap();
 283        let mut server = Self::new_internal(
 284            server_id,
 285            stdin,
 286            stdout,
 287            Some(stderr),
 288            stderr_capture,
 289            Some(server),
 290            root_path,
 291            code_action_kinds,
 292            cx,
 293            move |notification| {
 294                log::info!(
 295                    "Language server with id {} sent unhandled notification {}:\n{}",
 296                    server_id,
 297                    notification.method,
 298                    serde_json::to_string_pretty(
 299                        &notification
 300                            .params
 301                            .and_then(|params| Value::from_str(params.get()).ok())
 302                            .unwrap_or(Value::Null)
 303                    )
 304                    .unwrap(),
 305                );
 306            },
 307        );
 308
 309        if let Some(name) = binary.path.file_name() {
 310            server.name = name.to_string_lossy().into();
 311        }
 312
 313        Ok(server)
 314    }
 315
 316    #[allow(clippy::too_many_arguments)]
 317    fn new_internal<Stdin, Stdout, Stderr, F>(
 318        server_id: LanguageServerId,
 319        stdin: Stdin,
 320        stdout: Stdout,
 321        stderr: Option<Stderr>,
 322        stderr_capture: Arc<Mutex<Option<String>>>,
 323        server: Option<Child>,
 324        root_path: &Path,
 325        code_action_kinds: Option<Vec<CodeActionKind>>,
 326        cx: AsyncAppContext,
 327        on_unhandled_notification: F,
 328    ) -> Self
 329    where
 330        Stdin: AsyncWrite + Unpin + Send + 'static,
 331        Stdout: AsyncRead + Unpin + Send + 'static,
 332        Stderr: AsyncRead + Unpin + Send + 'static,
 333        F: FnMut(AnyNotification) + 'static + Send + Sync + Clone,
 334    {
 335        let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
 336        let (output_done_tx, output_done_rx) = barrier::channel();
 337        let notification_handlers =
 338            Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
 339        let response_handlers =
 340            Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
 341        let io_handlers = Arc::new(Mutex::new(HashMap::default()));
 342
 343        let stdout_input_task = cx.spawn({
 344            let on_unhandled_notification = on_unhandled_notification.clone();
 345            let notification_handlers = notification_handlers.clone();
 346            let response_handlers = response_handlers.clone();
 347            let io_handlers = io_handlers.clone();
 348            move |cx| {
 349                Self::handle_input(
 350                    stdout,
 351                    on_unhandled_notification,
 352                    notification_handlers,
 353                    response_handlers,
 354                    io_handlers,
 355                    cx,
 356                )
 357                .log_err()
 358            }
 359        });
 360        let stderr_input_task = stderr
 361            .map(|stderr| {
 362                let io_handlers = io_handlers.clone();
 363                let stderr_captures = stderr_capture.clone();
 364                cx.spawn(|_| Self::handle_stderr(stderr, io_handlers, stderr_captures).log_err())
 365            })
 366            .unwrap_or_else(|| Task::Ready(Some(None)));
 367        let input_task = cx.spawn(|_| async move {
 368            let (stdout, stderr) = futures::join!(stdout_input_task, stderr_input_task);
 369            stdout.or(stderr)
 370        });
 371        let output_task = cx.background_executor().spawn({
 372            Self::handle_output(
 373                stdin,
 374                outbound_rx,
 375                output_done_tx,
 376                response_handlers.clone(),
 377                io_handlers.clone(),
 378            )
 379            .log_err()
 380        });
 381
 382        Self {
 383            server_id,
 384            notification_handlers,
 385            response_handlers,
 386            io_handlers,
 387            name: "".into(),
 388            capabilities: Default::default(),
 389            code_action_kinds,
 390            next_id: Default::default(),
 391            outbound_tx,
 392            executor: cx.background_executor().clone(),
 393            io_tasks: Mutex::new(Some((input_task, output_task))),
 394            output_done_rx: Mutex::new(Some(output_done_rx)),
 395            root_path: root_path.to_path_buf(),
 396            server: Arc::new(Mutex::new(server)),
 397        }
 398    }
 399
 400    /// List of code action kinds this language server reports being able to emit.
 401    pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
 402        self.code_action_kinds.clone()
 403    }
 404
 405    async fn handle_input<Stdout, F>(
 406        stdout: Stdout,
 407        mut on_unhandled_notification: F,
 408        notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
 409        response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
 410        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 411        cx: AsyncAppContext,
 412    ) -> anyhow::Result<()>
 413    where
 414        Stdout: AsyncRead + Unpin + Send + 'static,
 415        F: FnMut(AnyNotification) + 'static + Send,
 416    {
 417        let mut stdout = BufReader::new(stdout);
 418        let _clear_response_handlers = util::defer({
 419            let response_handlers = response_handlers.clone();
 420            move || {
 421                response_handlers.lock().take();
 422            }
 423        });
 424        let mut buffer = Vec::new();
 425        loop {
 426            buffer.clear();
 427
 428            read_headers(&mut stdout, &mut buffer).await?;
 429
 430            let headers = std::str::from_utf8(&buffer)?;
 431
 432            let message_len = headers
 433                .split('\n')
 434                .find(|line| line.starts_with(CONTENT_LEN_HEADER))
 435                .and_then(|line| line.strip_prefix(CONTENT_LEN_HEADER))
 436                .ok_or_else(|| anyhow!("invalid LSP message header {headers:?}"))?
 437                .trim_end()
 438                .parse()?;
 439
 440            buffer.resize(message_len, 0);
 441            stdout.read_exact(&mut buffer).await?;
 442
 443            if let Ok(message) = str::from_utf8(&buffer) {
 444                log::trace!("incoming message: {message}");
 445                for handler in io_handlers.lock().values_mut() {
 446                    handler(IoKind::StdOut, message);
 447                }
 448            }
 449
 450            if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
 451                if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
 452                    handler(
 453                        msg.id,
 454                        msg.params.map(|params| params.get()).unwrap_or("null"),
 455                        cx.clone(),
 456                    );
 457                } else {
 458                    on_unhandled_notification(msg);
 459                }
 460            } else if let Ok(AnyResponse {
 461                id, error, result, ..
 462            }) = serde_json::from_slice(&buffer)
 463            {
 464                if let Some(handler) = response_handlers
 465                    .lock()
 466                    .as_mut()
 467                    .and_then(|handlers| handlers.remove(&id))
 468                {
 469                    if let Some(error) = error {
 470                        handler(Err(error));
 471                    } else if let Some(result) = result {
 472                        handler(Ok(result.get().into()));
 473                    } else {
 474                        handler(Ok("null".into()));
 475                    }
 476                }
 477            } else {
 478                warn!(
 479                    "failed to deserialize LSP message:\n{}",
 480                    std::str::from_utf8(&buffer)?
 481                );
 482            }
 483
 484            // Don't starve the main thread when receiving lots of messages at once.
 485            smol::future::yield_now().await;
 486        }
 487    }
 488
 489    async fn handle_stderr<Stderr>(
 490        stderr: Stderr,
 491        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 492        stderr_capture: Arc<Mutex<Option<String>>>,
 493    ) -> anyhow::Result<()>
 494    where
 495        Stderr: AsyncRead + Unpin + Send + 'static,
 496    {
 497        let mut stderr = BufReader::new(stderr);
 498        let mut buffer = Vec::new();
 499
 500        loop {
 501            buffer.clear();
 502
 503            let bytes_read = stderr.read_until(b'\n', &mut buffer).await?;
 504            if bytes_read == 0 {
 505                return Ok(());
 506            }
 507
 508            if let Ok(message) = str::from_utf8(&buffer) {
 509                log::trace!("incoming stderr message:{message}");
 510                for handler in io_handlers.lock().values_mut() {
 511                    handler(IoKind::StdErr, message);
 512                }
 513
 514                if let Some(stderr) = stderr_capture.lock().as_mut() {
 515                    stderr.push_str(message);
 516                }
 517            }
 518
 519            // Don't starve the main thread when receiving lots of messages at once.
 520            smol::future::yield_now().await;
 521        }
 522    }
 523
 524    async fn handle_output<Stdin>(
 525        stdin: Stdin,
 526        outbound_rx: channel::Receiver<String>,
 527        output_done_tx: barrier::Sender,
 528        response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
 529        io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
 530    ) -> anyhow::Result<()>
 531    where
 532        Stdin: AsyncWrite + Unpin + Send + 'static,
 533    {
 534        let mut stdin = BufWriter::new(stdin);
 535        let _clear_response_handlers = util::defer({
 536            let response_handlers = response_handlers.clone();
 537            move || {
 538                response_handlers.lock().take();
 539            }
 540        });
 541        let mut content_len_buffer = Vec::new();
 542        while let Ok(message) = outbound_rx.recv().await {
 543            log::trace!("outgoing message:{}", message);
 544            for handler in io_handlers.lock().values_mut() {
 545                handler(IoKind::StdIn, &message);
 546            }
 547
 548            content_len_buffer.clear();
 549            write!(content_len_buffer, "{}", message.len()).unwrap();
 550            stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
 551            stdin.write_all(&content_len_buffer).await?;
 552            stdin.write_all("\r\n\r\n".as_bytes()).await?;
 553            stdin.write_all(message.as_bytes()).await?;
 554            stdin.flush().await?;
 555        }
 556        drop(output_done_tx);
 557        Ok(())
 558    }
 559
 560    /// Initializes a language server by sending the `Initialize` request.
 561    /// Note that `options` is used directly to construct [`InitializeParams`], which is why it is owned.
 562    ///
 563    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#initialize)
 564    pub fn initialize(
 565        mut self,
 566        options: Option<Value>,
 567        cx: &AppContext,
 568    ) -> Task<Result<Arc<Self>>> {
 569        let root_uri = Url::from_file_path(&self.root_path).unwrap();
 570        #[allow(deprecated)]
 571        let params = InitializeParams {
 572            process_id: None,
 573            root_path: None,
 574            root_uri: Some(root_uri.clone()),
 575            initialization_options: options,
 576            capabilities: ClientCapabilities {
 577                workspace: Some(WorkspaceClientCapabilities {
 578                    configuration: Some(true),
 579                    did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
 580                        dynamic_registration: Some(true),
 581                        relative_pattern_support: Some(true),
 582                    }),
 583                    did_change_configuration: Some(DynamicRegistrationClientCapabilities {
 584                        dynamic_registration: Some(true),
 585                    }),
 586                    workspace_folders: Some(true),
 587                    symbol: Some(WorkspaceSymbolClientCapabilities {
 588                        resolve_support: None,
 589                        ..WorkspaceSymbolClientCapabilities::default()
 590                    }),
 591                    inlay_hint: Some(InlayHintWorkspaceClientCapabilities {
 592                        refresh_support: Some(true),
 593                    }),
 594                    diagnostic: Some(DiagnosticWorkspaceClientCapabilities {
 595                        refresh_support: None,
 596                    }),
 597                    workspace_edit: Some(WorkspaceEditClientCapabilities {
 598                        resource_operations: Some(vec![
 599                            ResourceOperationKind::Create,
 600                            ResourceOperationKind::Rename,
 601                            ResourceOperationKind::Delete,
 602                        ]),
 603                        document_changes: Some(true),
 604                        ..WorkspaceEditClientCapabilities::default()
 605                    }),
 606                    ..Default::default()
 607                }),
 608                text_document: Some(TextDocumentClientCapabilities {
 609                    definition: Some(GotoCapability {
 610                        link_support: Some(true),
 611                        dynamic_registration: None,
 612                    }),
 613                    code_action: Some(CodeActionClientCapabilities {
 614                        code_action_literal_support: Some(CodeActionLiteralSupport {
 615                            code_action_kind: CodeActionKindLiteralSupport {
 616                                value_set: vec![
 617                                    CodeActionKind::REFACTOR.as_str().into(),
 618                                    CodeActionKind::QUICKFIX.as_str().into(),
 619                                    CodeActionKind::SOURCE.as_str().into(),
 620                                ],
 621                            },
 622                        }),
 623                        data_support: Some(true),
 624                        resolve_support: Some(CodeActionCapabilityResolveSupport {
 625                            properties: vec![
 626                                "kind".to_string(),
 627                                "diagnostics".to_string(),
 628                                "isPreferred".to_string(),
 629                                "disabled".to_string(),
 630                                "edit".to_string(),
 631                                "command".to_string(),
 632                            ],
 633                        }),
 634                        ..Default::default()
 635                    }),
 636                    completion: Some(CompletionClientCapabilities {
 637                        completion_item: Some(CompletionItemCapability {
 638                            snippet_support: Some(true),
 639                            resolve_support: Some(CompletionItemCapabilityResolveSupport {
 640                                properties: vec![
 641                                    "documentation".to_string(),
 642                                    "additionalTextEdits".to_string(),
 643                                ],
 644                            }),
 645                            insert_replace_support: Some(true),
 646                            ..Default::default()
 647                        }),
 648                        completion_list: Some(CompletionListCapability {
 649                            item_defaults: Some(vec![
 650                                "commitCharacters".to_owned(),
 651                                "editRange".to_owned(),
 652                                "insertTextMode".to_owned(),
 653                                "data".to_owned(),
 654                            ]),
 655                        }),
 656                        ..Default::default()
 657                    }),
 658                    rename: Some(RenameClientCapabilities {
 659                        prepare_support: Some(true),
 660                        ..Default::default()
 661                    }),
 662                    hover: Some(HoverClientCapabilities {
 663                        content_format: Some(vec![MarkupKind::Markdown]),
 664                        dynamic_registration: None,
 665                    }),
 666                    inlay_hint: Some(InlayHintClientCapabilities {
 667                        resolve_support: Some(InlayHintResolveClientCapabilities {
 668                            properties: vec![
 669                                "textEdits".to_string(),
 670                                "tooltip".to_string(),
 671                                "label.tooltip".to_string(),
 672                                "label.location".to_string(),
 673                                "label.command".to_string(),
 674                            ],
 675                        }),
 676                        dynamic_registration: Some(false),
 677                    }),
 678                    publish_diagnostics: Some(PublishDiagnosticsClientCapabilities {
 679                        related_information: Some(true),
 680                        ..Default::default()
 681                    }),
 682                    formatting: Some(DynamicRegistrationClientCapabilities {
 683                        dynamic_registration: None,
 684                    }),
 685                    on_type_formatting: Some(DynamicRegistrationClientCapabilities {
 686                        dynamic_registration: None,
 687                    }),
 688                    diagnostic: Some(DiagnosticClientCapabilities {
 689                        related_document_support: Some(true),
 690                        dynamic_registration: None,
 691                    }),
 692                    ..Default::default()
 693                }),
 694                experimental: Some(json!({
 695                    "serverStatusNotification": true,
 696                })),
 697                window: Some(WindowClientCapabilities {
 698                    work_done_progress: Some(true),
 699                    ..Default::default()
 700                }),
 701                general: None,
 702            },
 703            trace: None,
 704            workspace_folders: Some(vec![WorkspaceFolder {
 705                uri: root_uri,
 706                name: Default::default(),
 707            }]),
 708            client_info: release_channel::ReleaseChannel::try_global(cx).map(|release_channel| {
 709                ClientInfo {
 710                    name: release_channel.display_name().to_string(),
 711                    version: Some(release_channel::AppVersion::global(cx).to_string()),
 712                }
 713            }),
 714            locale: None,
 715        };
 716
 717        cx.spawn(|_| async move {
 718            let response = self.request::<request::Initialize>(params).await?;
 719            if let Some(info) = response.server_info {
 720                self.name = info.name.into();
 721            }
 722            self.capabilities = response.capabilities;
 723
 724            self.notify::<notification::Initialized>(InitializedParams {})?;
 725            Ok(Arc::new(self))
 726        })
 727    }
 728
 729    /// Sends a shutdown request to the language server process and prepares the [`LanguageServer`] to be dropped.
 730    pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
 731        if let Some(tasks) = self.io_tasks.lock().take() {
 732            let response_handlers = self.response_handlers.clone();
 733            let next_id = AtomicI32::new(self.next_id.load(SeqCst));
 734            let outbound_tx = self.outbound_tx.clone();
 735            let executor = self.executor.clone();
 736            let mut output_done = self.output_done_rx.lock().take().unwrap();
 737            let shutdown_request = Self::request_internal::<request::Shutdown>(
 738                &next_id,
 739                &response_handlers,
 740                &outbound_tx,
 741                &executor,
 742                (),
 743            );
 744            let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
 745            outbound_tx.close();
 746
 747            let server = self.server.clone();
 748            let name = self.name.clone();
 749            let mut timer = self.executor.timer(SERVER_SHUTDOWN_TIMEOUT).fuse();
 750            Some(
 751                async move {
 752                    log::debug!("language server shutdown started");
 753
 754                    select! {
 755                        request_result = shutdown_request.fuse() => {
 756                            request_result?;
 757                        }
 758
 759                        _ = timer => {
 760                            log::info!("timeout waiting for language server {name} to shutdown");
 761                        },
 762                    }
 763
 764                    response_handlers.lock().take();
 765                    exit?;
 766                    output_done.recv().await;
 767                    server.lock().take().map(|mut child| child.kill());
 768                    log::debug!("language server shutdown finished");
 769
 770                    drop(tasks);
 771                    anyhow::Ok(())
 772                }
 773                .log_err(),
 774            )
 775        } else {
 776            None
 777        }
 778    }
 779
 780    /// Register a handler to handle incoming LSP notifications.
 781    ///
 782    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
 783    #[must_use]
 784    pub fn on_notification<T, F>(&self, f: F) -> Subscription
 785    where
 786        T: notification::Notification,
 787        F: 'static + Send + FnMut(T::Params, AsyncAppContext),
 788    {
 789        self.on_custom_notification(T::METHOD, f)
 790    }
 791
 792    /// Register a handler to handle incoming LSP requests.
 793    ///
 794    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 795    #[must_use]
 796    pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
 797    where
 798        T: request::Request,
 799        T::Params: 'static + Send,
 800        F: 'static + FnMut(T::Params, AsyncAppContext) -> Fut + Send,
 801        Fut: 'static + Future<Output = Result<T::Result>>,
 802    {
 803        self.on_custom_request(T::METHOD, f)
 804    }
 805
 806    /// Registers a handler to inspect all language server process stdio.
 807    #[must_use]
 808    pub fn on_io<F>(&self, f: F) -> Subscription
 809    where
 810        F: 'static + Send + FnMut(IoKind, &str),
 811    {
 812        let id = self.next_id.fetch_add(1, SeqCst);
 813        self.io_handlers.lock().insert(id, Box::new(f));
 814        Subscription::Io {
 815            id,
 816            io_handlers: Some(Arc::downgrade(&self.io_handlers)),
 817        }
 818    }
 819
 820    /// Removes a request handler registers via [`Self::on_request`].
 821    pub fn remove_request_handler<T: request::Request>(&self) {
 822        self.notification_handlers.lock().remove(T::METHOD);
 823    }
 824
 825    /// Removes a notification handler registers via [`Self::on_notification`].
 826    pub fn remove_notification_handler<T: notification::Notification>(&self) {
 827        self.notification_handlers.lock().remove(T::METHOD);
 828    }
 829
 830    /// Checks if a notification handler has been registered via [`Self::on_notification`].
 831    pub fn has_notification_handler<T: notification::Notification>(&self) -> bool {
 832        self.notification_handlers.lock().contains_key(T::METHOD)
 833    }
 834
 835    #[must_use]
 836    fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
 837    where
 838        F: 'static + FnMut(Params, AsyncAppContext) + Send,
 839        Params: DeserializeOwned,
 840    {
 841        let prev_handler = self.notification_handlers.lock().insert(
 842            method,
 843            Box::new(move |_, params, cx| {
 844                if let Some(params) = serde_json::from_str(params).log_err() {
 845                    f(params, cx);
 846                }
 847            }),
 848        );
 849        assert!(
 850            prev_handler.is_none(),
 851            "registered multiple handlers for the same LSP method"
 852        );
 853        Subscription::Notification {
 854            method,
 855            notification_handlers: Some(self.notification_handlers.clone()),
 856        }
 857    }
 858
 859    #[must_use]
 860    fn on_custom_request<Params, Res, Fut, F>(&self, method: &'static str, mut f: F) -> Subscription
 861    where
 862        F: 'static + FnMut(Params, AsyncAppContext) -> Fut + Send,
 863        Fut: 'static + Future<Output = Result<Res>>,
 864        Params: DeserializeOwned + Send + 'static,
 865        Res: Serialize,
 866    {
 867        let outbound_tx = self.outbound_tx.clone();
 868        let prev_handler = self.notification_handlers.lock().insert(
 869            method,
 870            Box::new(move |id, params, cx| {
 871                if let Some(id) = id {
 872                    match serde_json::from_str(params) {
 873                        Ok(params) => {
 874                            let response = f(params, cx.clone());
 875                            cx.foreground_executor()
 876                                .spawn({
 877                                    let outbound_tx = outbound_tx.clone();
 878                                    async move {
 879                                        let response = match response.await {
 880                                            Ok(result) => Response {
 881                                                jsonrpc: JSON_RPC_VERSION,
 882                                                id,
 883                                                value: LspResult::Ok(Some(result)),
 884                                            },
 885                                            Err(error) => Response {
 886                                                jsonrpc: JSON_RPC_VERSION,
 887                                                id,
 888                                                value: LspResult::Error(Some(Error {
 889                                                    message: error.to_string(),
 890                                                })),
 891                                            },
 892                                        };
 893                                        if let Some(response) =
 894                                            serde_json::to_string(&response).log_err()
 895                                        {
 896                                            outbound_tx.try_send(response).ok();
 897                                        }
 898                                    }
 899                                })
 900                                .detach();
 901                        }
 902
 903                        Err(error) => {
 904                            log::error!(
 905                                "error deserializing {} request: {:?}, message: {:?}",
 906                                method,
 907                                error,
 908                                params
 909                            );
 910                            let response = AnyResponse {
 911                                jsonrpc: JSON_RPC_VERSION,
 912                                id,
 913                                result: None,
 914                                error: Some(Error {
 915                                    message: error.to_string(),
 916                                }),
 917                            };
 918                            if let Some(response) = serde_json::to_string(&response).log_err() {
 919                                outbound_tx.try_send(response).ok();
 920                            }
 921                        }
 922                    }
 923                }
 924            }),
 925        );
 926        assert!(
 927            prev_handler.is_none(),
 928            "registered multiple handlers for the same LSP method"
 929        );
 930        Subscription::Notification {
 931            method,
 932            notification_handlers: Some(self.notification_handlers.clone()),
 933        }
 934    }
 935
 936    /// Get the name of the running language server.
 937    pub fn name(&self) -> &str {
 938        &self.name
 939    }
 940
 941    /// Get the reported capabilities of the running language server.
 942    pub fn capabilities(&self) -> &ServerCapabilities {
 943        &self.capabilities
 944    }
 945
 946    /// Get the id of the running language server.
 947    pub fn server_id(&self) -> LanguageServerId {
 948        self.server_id
 949    }
 950
 951    /// Get the root path of the project the language server is running against.
 952    pub fn root_path(&self) -> &PathBuf {
 953        &self.root_path
 954    }
 955
 956    /// Sends a RPC request to the language server.
 957    ///
 958    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
 959    pub fn request<T: request::Request>(
 960        &self,
 961        params: T::Params,
 962    ) -> impl LspRequestFuture<Result<T::Result>>
 963    where
 964        T::Result: 'static + Send,
 965    {
 966        Self::request_internal::<T>(
 967            &self.next_id,
 968            &self.response_handlers,
 969            &self.outbound_tx,
 970            &self.executor,
 971            params,
 972        )
 973    }
 974
 975    fn request_internal<T: request::Request>(
 976        next_id: &AtomicI32,
 977        response_handlers: &Mutex<Option<HashMap<RequestId, ResponseHandler>>>,
 978        outbound_tx: &channel::Sender<String>,
 979        executor: &BackgroundExecutor,
 980        params: T::Params,
 981    ) -> impl LspRequestFuture<Result<T::Result>>
 982    where
 983        T::Result: 'static + Send,
 984    {
 985        let id = next_id.fetch_add(1, SeqCst);
 986        let message = serde_json::to_string(&Request {
 987            jsonrpc: JSON_RPC_VERSION,
 988            id: RequestId::Int(id),
 989            method: T::METHOD,
 990            params,
 991        })
 992        .unwrap();
 993
 994        let (tx, rx) = oneshot::channel();
 995        let handle_response = response_handlers
 996            .lock()
 997            .as_mut()
 998            .ok_or_else(|| anyhow!("server shut down"))
 999            .map(|handlers| {
1000                let executor = executor.clone();
1001                handlers.insert(
1002                    RequestId::Int(id),
1003                    Box::new(move |result| {
1004                        executor
1005                            .spawn(async move {
1006                                let response = match result {
1007                                    Ok(response) => match serde_json::from_str(&response) {
1008                                        Ok(deserialized) => Ok(deserialized),
1009                                        Err(error) => {
1010                                            log::error!("failed to deserialize response from language server: {}. response from language server: {:?}", error, response);
1011                                            Err(error).context("failed to deserialize response")
1012                                        }
1013                                    }
1014                                    Err(error) => Err(anyhow!("{}", error.message)),
1015                                };
1016                                _ = tx.send(response);
1017                            })
1018                            .detach();
1019                    }),
1020                );
1021            });
1022
1023        let send = outbound_tx
1024            .try_send(message)
1025            .context("failed to write to language server's stdin");
1026
1027        let outbound_tx = outbound_tx.downgrade();
1028        let mut timeout = executor.timer(LSP_REQUEST_TIMEOUT).fuse();
1029        let started = Instant::now();
1030        LspRequest::new(id, async move {
1031            handle_response?;
1032            send?;
1033
1034            let cancel_on_drop = util::defer(move || {
1035                if let Some(outbound_tx) = outbound_tx.upgrade() {
1036                    Self::notify_internal::<notification::Cancel>(
1037                        &outbound_tx,
1038                        CancelParams {
1039                            id: NumberOrString::Number(id),
1040                        },
1041                    )
1042                    .log_err();
1043                }
1044            });
1045
1046            let method = T::METHOD;
1047            select! {
1048                response = rx.fuse() => {
1049                    let elapsed = started.elapsed();
1050                    log::trace!("Took {elapsed:?} to receive response to {method:?} id {id}");
1051                    cancel_on_drop.abort();
1052                    response?
1053                }
1054
1055                _ = timeout => {
1056                    log::error!("Cancelled LSP request task for {method:?} id {id} which took over {LSP_REQUEST_TIMEOUT:?}");
1057                    anyhow::bail!("LSP request timeout");
1058                }
1059            }
1060        })
1061    }
1062
1063    /// Sends a RPC notification to the language server.
1064    ///
1065    /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
1066    pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
1067        Self::notify_internal::<T>(&self.outbound_tx, params)
1068    }
1069
1070    fn notify_internal<T: notification::Notification>(
1071        outbound_tx: &channel::Sender<String>,
1072        params: T::Params,
1073    ) -> Result<()> {
1074        let message = serde_json::to_string(&Notification {
1075            jsonrpc: JSON_RPC_VERSION,
1076            method: T::METHOD,
1077            params,
1078        })
1079        .unwrap();
1080        outbound_tx.try_send(message)?;
1081        Ok(())
1082    }
1083}
1084
1085impl Drop for LanguageServer {
1086    fn drop(&mut self) {
1087        if let Some(shutdown) = self.shutdown() {
1088            self.executor.spawn(shutdown).detach();
1089        }
1090    }
1091}
1092
1093impl Subscription {
1094    /// Detaching a subscription handle prevents it from unsubscribing on drop.
1095    pub fn detach(&mut self) {
1096        match self {
1097            Subscription::Notification {
1098                notification_handlers,
1099                ..
1100            } => *notification_handlers = None,
1101            Subscription::Io { io_handlers, .. } => *io_handlers = None,
1102        }
1103    }
1104}
1105
1106impl fmt::Display for LanguageServerId {
1107    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1108        self.0.fmt(f)
1109    }
1110}
1111
1112impl fmt::Debug for LanguageServer {
1113    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1114        f.debug_struct("LanguageServer")
1115            .field("id", &self.server_id.0)
1116            .field("name", &self.name)
1117            .finish_non_exhaustive()
1118    }
1119}
1120
1121impl Drop for Subscription {
1122    fn drop(&mut self) {
1123        match self {
1124            Subscription::Notification {
1125                method,
1126                notification_handlers,
1127            } => {
1128                if let Some(handlers) = notification_handlers {
1129                    handlers.lock().remove(method);
1130                }
1131            }
1132            Subscription::Io { id, io_handlers } => {
1133                if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
1134                    io_handlers.lock().remove(id);
1135                }
1136            }
1137        }
1138    }
1139}
1140
1141/// Mock language server for use in tests.
1142#[cfg(any(test, feature = "test-support"))]
1143#[derive(Clone)]
1144pub struct FakeLanguageServer {
1145    pub binary: LanguageServerBinary,
1146    pub server: Arc<LanguageServer>,
1147    notifications_rx: channel::Receiver<(String, String)>,
1148}
1149
1150#[cfg(any(test, feature = "test-support"))]
1151impl FakeLanguageServer {
1152    /// Construct a fake language server.
1153    pub fn new(
1154        server_id: LanguageServerId,
1155        binary: LanguageServerBinary,
1156        name: String,
1157        capabilities: ServerCapabilities,
1158        cx: AsyncAppContext,
1159    ) -> (LanguageServer, FakeLanguageServer) {
1160        let (stdin_writer, stdin_reader) = async_pipe::pipe();
1161        let (stdout_writer, stdout_reader) = async_pipe::pipe();
1162        let (notifications_tx, notifications_rx) = channel::unbounded();
1163
1164        let mut server = LanguageServer::new_internal(
1165            server_id,
1166            stdin_writer,
1167            stdout_reader,
1168            None::<async_pipe::PipeReader>,
1169            Arc::new(Mutex::new(None)),
1170            None,
1171            Path::new("/"),
1172            None,
1173            cx.clone(),
1174            |_| {},
1175        );
1176        server.name = name.as_str().into();
1177        let fake = FakeLanguageServer {
1178            binary,
1179            server: Arc::new({
1180                let mut server = LanguageServer::new_internal(
1181                    server_id,
1182                    stdout_writer,
1183                    stdin_reader,
1184                    None::<async_pipe::PipeReader>,
1185                    Arc::new(Mutex::new(None)),
1186                    None,
1187                    Path::new("/"),
1188                    None,
1189                    cx,
1190                    move |msg| {
1191                        notifications_tx
1192                            .try_send((
1193                                msg.method.to_string(),
1194                                msg.params
1195                                    .map(|raw_value| raw_value.get())
1196                                    .unwrap_or("null")
1197                                    .to_string(),
1198                            ))
1199                            .ok();
1200                    },
1201                );
1202                server.name = name.as_str().into();
1203                server
1204            }),
1205            notifications_rx,
1206        };
1207        fake.handle_request::<request::Initialize, _, _>({
1208            let capabilities = capabilities;
1209            move |_, _| {
1210                let capabilities = capabilities.clone();
1211                let name = name.clone();
1212                async move {
1213                    Ok(InitializeResult {
1214                        capabilities,
1215                        server_info: Some(ServerInfo {
1216                            name,
1217                            ..Default::default()
1218                        }),
1219                    })
1220                }
1221            }
1222        });
1223
1224        (server, fake)
1225    }
1226}
1227
1228#[cfg(any(test, feature = "test-support"))]
1229impl LanguageServer {
1230    pub fn full_capabilities() -> ServerCapabilities {
1231        ServerCapabilities {
1232            document_highlight_provider: Some(OneOf::Left(true)),
1233            code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
1234            document_formatting_provider: Some(OneOf::Left(true)),
1235            document_range_formatting_provider: Some(OneOf::Left(true)),
1236            definition_provider: Some(OneOf::Left(true)),
1237            implementation_provider: Some(ImplementationProviderCapability::Simple(true)),
1238            type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
1239            ..Default::default()
1240        }
1241    }
1242}
1243
1244#[cfg(any(test, feature = "test-support"))]
1245impl FakeLanguageServer {
1246    /// See [`LanguageServer::notify`].
1247    pub fn notify<T: notification::Notification>(&self, params: T::Params) {
1248        self.server.notify::<T>(params).ok();
1249    }
1250
1251    /// See [`LanguageServer::request`].
1252    pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
1253    where
1254        T: request::Request,
1255        T::Result: 'static + Send,
1256    {
1257        self.server.executor.start_waiting();
1258        self.server.request::<T>(params).await
1259    }
1260
1261    /// Attempts [`Self::try_receive_notification`], unwrapping if it has not received the specified type yet.
1262    pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
1263        self.server.executor.start_waiting();
1264        self.try_receive_notification::<T>().await.unwrap()
1265    }
1266
1267    /// Consumes the notification channel until it finds a notification for the specified type.
1268    pub async fn try_receive_notification<T: notification::Notification>(
1269        &mut self,
1270    ) -> Option<T::Params> {
1271        use futures::StreamExt as _;
1272
1273        loop {
1274            let (method, params) = self.notifications_rx.next().await?;
1275            if method == T::METHOD {
1276                return Some(serde_json::from_str::<T::Params>(&params).unwrap());
1277            } else {
1278                log::info!("skipping message in fake language server {:?}", params);
1279            }
1280        }
1281    }
1282
1283    /// Registers a handler for a specific kind of request. Removes any existing handler for specified request type.
1284    pub fn handle_request<T, F, Fut>(
1285        &self,
1286        mut handler: F,
1287    ) -> futures::channel::mpsc::UnboundedReceiver<()>
1288    where
1289        T: 'static + request::Request,
1290        T::Params: 'static + Send,
1291        F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
1292        Fut: 'static + Send + Future<Output = Result<T::Result>>,
1293    {
1294        let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
1295        self.server.remove_request_handler::<T>();
1296        self.server
1297            .on_request::<T, _, _>(move |params, cx| {
1298                let result = handler(params, cx.clone());
1299                let responded_tx = responded_tx.clone();
1300                let executor = cx.background_executor().clone();
1301                async move {
1302                    executor.simulate_random_delay().await;
1303                    let result = result.await;
1304                    responded_tx.unbounded_send(()).ok();
1305                    result
1306                }
1307            })
1308            .detach();
1309        responded_rx
1310    }
1311
1312    /// Registers a handler for a specific kind of notification. Removes any existing handler for specified notification type.
1313    pub fn handle_notification<T, F>(
1314        &self,
1315        mut handler: F,
1316    ) -> futures::channel::mpsc::UnboundedReceiver<()>
1317    where
1318        T: 'static + notification::Notification,
1319        T::Params: 'static + Send,
1320        F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
1321    {
1322        let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
1323        self.server.remove_notification_handler::<T>();
1324        self.server
1325            .on_notification::<T, _>(move |params, cx| {
1326                handler(params, cx.clone());
1327                handled_tx.unbounded_send(()).ok();
1328            })
1329            .detach();
1330        handled_rx
1331    }
1332
1333    /// Removes any existing handler for specified notification type.
1334    pub fn remove_request_handler<T>(&mut self)
1335    where
1336        T: 'static + request::Request,
1337    {
1338        self.server.remove_request_handler::<T>();
1339    }
1340
1341    /// Simulate that the server has started work and notifies about its progress with the specified token.
1342    pub async fn start_progress(&self, token: impl Into<String>) {
1343        let token = token.into();
1344        self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
1345            token: NumberOrString::String(token.clone()),
1346        })
1347        .await
1348        .unwrap();
1349        self.notify::<notification::Progress>(ProgressParams {
1350            token: NumberOrString::String(token),
1351            value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
1352        });
1353    }
1354
1355    /// Simulate that the server has completed work and notifies about that with the specified token.
1356    pub fn end_progress(&self, token: impl Into<String>) {
1357        self.notify::<notification::Progress>(ProgressParams {
1358            token: NumberOrString::String(token.into()),
1359            value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1360        });
1361    }
1362}
1363
1364pub(self) async fn read_headers<Stdout>(
1365    reader: &mut BufReader<Stdout>,
1366    buffer: &mut Vec<u8>,
1367) -> Result<()>
1368where
1369    Stdout: AsyncRead + Unpin + Send + 'static,
1370{
1371    loop {
1372        if buffer.len() >= HEADER_DELIMITER.len()
1373            && buffer[(buffer.len() - HEADER_DELIMITER.len())..] == HEADER_DELIMITER[..]
1374        {
1375            return Ok(());
1376        }
1377
1378        if reader.read_until(b'\n', buffer).await? == 0 {
1379            return Err(anyhow!("cannot read LSP message headers"));
1380        }
1381    }
1382}
1383
1384#[cfg(test)]
1385mod tests {
1386    use super::*;
1387    use gpui::TestAppContext;
1388
1389    #[ctor::ctor]
1390    fn init_logger() {
1391        if std::env::var("RUST_LOG").is_ok() {
1392            env_logger::init();
1393        }
1394    }
1395
1396    #[gpui::test]
1397    async fn test_fake(cx: &mut TestAppContext) {
1398        cx.update(|cx| {
1399            release_channel::init("0.0.0", cx);
1400        });
1401        let (server, mut fake) = FakeLanguageServer::new(
1402            LanguageServerId(0),
1403            LanguageServerBinary {
1404                path: "path/to/language-server".into(),
1405                arguments: vec![],
1406                env: None,
1407            },
1408            "the-lsp".to_string(),
1409            Default::default(),
1410            cx.to_async(),
1411        );
1412
1413        let (message_tx, message_rx) = channel::unbounded();
1414        let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1415        server
1416            .on_notification::<notification::ShowMessage, _>(move |params, _| {
1417                message_tx.try_send(params).unwrap()
1418            })
1419            .detach();
1420        server
1421            .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1422                diagnostics_tx.try_send(params).unwrap()
1423            })
1424            .detach();
1425
1426        let server = cx.update(|cx| server.initialize(None, cx)).await.unwrap();
1427        server
1428            .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1429                text_document: TextDocumentItem::new(
1430                    Url::from_str("file://a/b").unwrap(),
1431                    "rust".to_string(),
1432                    0,
1433                    "".to_string(),
1434                ),
1435            })
1436            .unwrap();
1437        assert_eq!(
1438            fake.receive_notification::<notification::DidOpenTextDocument>()
1439                .await
1440                .text_document
1441                .uri
1442                .as_str(),
1443            "file://a/b"
1444        );
1445
1446        fake.notify::<notification::ShowMessage>(ShowMessageParams {
1447            typ: MessageType::ERROR,
1448            message: "ok".to_string(),
1449        });
1450        fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1451            uri: Url::from_str("file://b/c").unwrap(),
1452            version: Some(5),
1453            diagnostics: vec![],
1454        });
1455        assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1456        assert_eq!(
1457            diagnostics_rx.recv().await.unwrap().uri.as_str(),
1458            "file://b/c"
1459        );
1460
1461        fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1462
1463        drop(server);
1464        fake.receive_notification::<notification::Exit>().await;
1465    }
1466
1467    #[gpui::test]
1468    async fn test_read_headers() {
1469        let mut buf = Vec::new();
1470        let mut reader = smol::io::BufReader::new(b"Content-Length: 123\r\n\r\n" as &[u8]);
1471        read_headers(&mut reader, &mut buf).await.unwrap();
1472        assert_eq!(buf, b"Content-Length: 123\r\n\r\n");
1473
1474        let mut buf = Vec::new();
1475        let mut reader = smol::io::BufReader::new(b"Content-Type: application/vscode-jsonrpc\r\nContent-Length: 1235\r\n\r\n{\"somecontent\":123}" as &[u8]);
1476        read_headers(&mut reader, &mut buf).await.unwrap();
1477        assert_eq!(
1478            buf,
1479            b"Content-Type: application/vscode-jsonrpc\r\nContent-Length: 1235\r\n\r\n"
1480        );
1481
1482        let mut buf = Vec::new();
1483        let mut reader = smol::io::BufReader::new(b"Content-Length: 1235\r\nContent-Type: application/vscode-jsonrpc\r\n\r\n{\"somecontent\":true}" as &[u8]);
1484        read_headers(&mut reader, &mut buf).await.unwrap();
1485        assert_eq!(
1486            buf,
1487            b"Content-Length: 1235\r\nContent-Type: application/vscode-jsonrpc\r\n\r\n"
1488        );
1489    }
1490
1491    #[gpui::test]
1492    fn test_deserialize_string_digit_id() {
1493        let json = r#"{"jsonrpc":"2.0","id":"2","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1494        let notification = serde_json::from_str::<AnyNotification>(json)
1495            .expect("message with string id should be parsed");
1496        let expected_id = RequestId::Str("2".to_string());
1497        assert_eq!(notification.id, Some(expected_id));
1498    }
1499
1500    #[gpui::test]
1501    fn test_deserialize_string_id() {
1502        let json = r#"{"jsonrpc":"2.0","id":"anythingAtAll","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1503        let notification = serde_json::from_str::<AnyNotification>(json)
1504            .expect("message with string id should be parsed");
1505        let expected_id = RequestId::Str("anythingAtAll".to_string());
1506        assert_eq!(notification.id, Some(expected_id));
1507    }
1508
1509    #[gpui::test]
1510    fn test_deserialize_int_id() {
1511        let json = r#"{"jsonrpc":"2.0","id":2,"method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1512        let notification = serde_json::from_str::<AnyNotification>(json)
1513            .expect("message with string id should be parsed");
1514        let expected_id = RequestId::Int(2);
1515        assert_eq!(notification.id, Some(expected_id));
1516    }
1517
1518    #[test]
1519    fn test_serialize_has_no_nulls() {
1520        // Ensure we're not setting both result and error variants. (ticket #10595)
1521        let no_tag = Response::<u32> {
1522            jsonrpc: "",
1523            id: RequestId::Int(0),
1524            value: LspResult::Ok(None),
1525        };
1526        assert_eq!(
1527            serde_json::to_string(&no_tag).unwrap(),
1528            "{\"jsonrpc\":\"\",\"id\":0,\"result\":null}"
1529        );
1530        let no_tag = Response::<u32> {
1531            jsonrpc: "",
1532            id: RequestId::Int(0),
1533            value: LspResult::Error(None),
1534        };
1535        assert_eq!(
1536            serde_json::to_string(&no_tag).unwrap(),
1537            "{\"jsonrpc\":\"\",\"id\":0,\"error\":null}"
1538        );
1539    }
1540}