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