lsp.rs

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