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, AsyncRead, AsyncWrite};
  8use gpui::{executor, AsyncAppContext, 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    future::Future,
 20    io::Write,
 21    path::PathBuf,
 22    str::FromStr,
 23    sync::{
 24        atomic::{AtomicUsize, Ordering::SeqCst},
 25        Arc,
 26    },
 27};
 28use std::{path::Path, process::Stdio};
 29use util::{ResultExt, TryFutureExt};
 30
 31const JSON_RPC_VERSION: &str = "2.0";
 32const CONTENT_LEN_HEADER: &str = "Content-Length: ";
 33
 34type NotificationHandler = Box<dyn Send + FnMut(Option<usize>, &str, AsyncAppContext)>;
 35type ResponseHandler = Box<dyn Send + FnOnce(Result<&str, Error>)>;
 36
 37pub struct LanguageServer {
 38    server_id: usize,
 39    next_id: AtomicUsize,
 40    outbound_tx: channel::Sender<Vec<u8>>,
 41    name: String,
 42    capabilities: ServerCapabilities,
 43    notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
 44    response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
 45    executor: Arc<executor::Background>,
 46    #[allow(clippy::type_complexity)]
 47    io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
 48    output_done_rx: Mutex<Option<barrier::Receiver>>,
 49    root_path: PathBuf,
 50    _server: Option<Child>,
 51}
 52
 53pub struct Subscription {
 54    method: &'static str,
 55    notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
 56}
 57
 58#[derive(Serialize, Deserialize)]
 59struct Request<'a, T> {
 60    jsonrpc: &'static str,
 61    id: usize,
 62    method: &'a str,
 63    params: T,
 64}
 65
 66#[derive(Serialize, Deserialize)]
 67struct AnyResponse<'a> {
 68    id: usize,
 69    #[serde(default)]
 70    error: Option<Error>,
 71    #[serde(borrow)]
 72    result: Option<&'a RawValue>,
 73}
 74
 75#[derive(Serialize)]
 76struct Response<T> {
 77    jsonrpc: &'static str,
 78    id: usize,
 79    result: Option<T>,
 80    error: Option<Error>,
 81}
 82
 83#[derive(Serialize, Deserialize)]
 84struct Notification<'a, T> {
 85    jsonrpc: &'static str,
 86    #[serde(borrow)]
 87    method: &'a str,
 88    params: T,
 89}
 90
 91#[derive(Deserialize)]
 92struct AnyNotification<'a> {
 93    #[serde(default)]
 94    id: Option<usize>,
 95    #[serde(borrow)]
 96    method: &'a str,
 97    #[serde(borrow)]
 98    params: &'a RawValue,
 99}
100
101#[derive(Debug, Serialize, Deserialize)]
102struct Error {
103    message: String,
104}
105
106impl LanguageServer {
107    pub fn new<T: AsRef<std::ffi::OsStr>>(
108        server_id: usize,
109        binary_path: &Path,
110        args: &[T],
111        root_path: &Path,
112        cx: AsyncAppContext,
113    ) -> Result<Self> {
114        let working_dir = if root_path.is_dir() {
115            root_path
116        } else {
117            root_path.parent().unwrap_or_else(|| Path::new("/"))
118        };
119        let mut server = process::Command::new(binary_path)
120            .current_dir(working_dir)
121            .args(args)
122            .stdin(Stdio::piped())
123            .stdout(Stdio::piped())
124            .stderr(Stdio::inherit())
125            .kill_on_drop(true)
126            .spawn()?;
127
128        let stdin = server.stdin.take().unwrap();
129        let stout = server.stdout.take().unwrap();
130
131        let mut server = Self::new_internal(
132            server_id,
133            stdin,
134            stout,
135            Some(server),
136            root_path,
137            cx,
138            |notification| {
139                log::info!(
140                    "unhandled notification {}:\n{}",
141                    notification.method,
142                    serde_json::to_string_pretty(
143                        &Value::from_str(notification.params.get()).unwrap()
144                    )
145                    .unwrap()
146                );
147            },
148        );
149        if let Some(name) = binary_path.file_name() {
150            server.name = name.to_string_lossy().to_string();
151        }
152        Ok(server)
153    }
154
155    fn new_internal<Stdin, Stdout, F>(
156        server_id: usize,
157        stdin: Stdin,
158        stdout: Stdout,
159        server: Option<Child>,
160        root_path: &Path,
161        cx: AsyncAppContext,
162        mut on_unhandled_notification: F,
163    ) -> Self
164    where
165        Stdin: AsyncWrite + Unpin + Send + 'static,
166        Stdout: AsyncRead + Unpin + Send + 'static,
167        F: FnMut(AnyNotification) + 'static + Send,
168    {
169        let mut stdin = BufWriter::new(stdin);
170        let mut stdout = BufReader::new(stdout);
171        let (outbound_tx, outbound_rx) = channel::unbounded::<Vec<u8>>();
172        let notification_handlers =
173            Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
174        let response_handlers =
175            Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
176        let input_task = cx.spawn(|cx| {
177            let notification_handlers = notification_handlers.clone();
178            let response_handlers = response_handlers.clone();
179            async move {
180                let _clear_response_handlers = util::defer({
181                    let response_handlers = response_handlers.clone();
182                    move || {
183                        response_handlers.lock().take();
184                    }
185                });
186                let mut buffer = Vec::new();
187                loop {
188                    buffer.clear();
189                    stdout.read_until(b'\n', &mut buffer).await?;
190                    stdout.read_until(b'\n', &mut buffer).await?;
191                    let message_len: usize = std::str::from_utf8(&buffer)?
192                        .strip_prefix(CONTENT_LEN_HEADER)
193                        .ok_or_else(|| anyhow!("invalid header"))?
194                        .trim_end()
195                        .parse()?;
196
197                    buffer.resize(message_len, 0);
198                    stdout.read_exact(&mut buffer).await?;
199                    log::trace!("incoming message:{}", String::from_utf8_lossy(&buffer));
200
201                    if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
202                        if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
203                            handler(msg.id, msg.params.get(), cx.clone());
204                        } else {
205                            on_unhandled_notification(msg);
206                        }
207                    } else if let Ok(AnyResponse { id, error, result }) =
208                        serde_json::from_slice(&buffer)
209                    {
210                        if let Some(handler) = response_handlers
211                            .lock()
212                            .as_mut()
213                            .and_then(|handlers| handlers.remove(&id))
214                        {
215                            if let Some(error) = error {
216                                handler(Err(error));
217                            } else if let Some(result) = result {
218                                handler(Ok(result.get()));
219                            } else {
220                                handler(Ok("null"));
221                            }
222                        }
223                    } else {
224                        warn!(
225                            "Failed to deserialize message:\n{}",
226                            std::str::from_utf8(&buffer)?
227                        );
228                    }
229
230                    // Don't starve the main thread when receiving lots of messages at once.
231                    smol::future::yield_now().await;
232                }
233            }
234            .log_err()
235        });
236        let (output_done_tx, output_done_rx) = barrier::channel();
237        let output_task = cx.background().spawn({
238            let response_handlers = response_handlers.clone();
239            async move {
240                let _clear_response_handlers = util::defer({
241                    let response_handlers = response_handlers.clone();
242                    move || {
243                        response_handlers.lock().take();
244                    }
245                });
246                let mut content_len_buffer = Vec::new();
247                while let Ok(message) = outbound_rx.recv().await {
248                    log::trace!("outgoing message:{}", String::from_utf8_lossy(&message));
249                    content_len_buffer.clear();
250                    write!(content_len_buffer, "{}", message.len()).unwrap();
251                    stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
252                    stdin.write_all(&content_len_buffer).await?;
253                    stdin.write_all("\r\n\r\n".as_bytes()).await?;
254                    stdin.write_all(&message).await?;
255                    stdin.flush().await?;
256                }
257                drop(output_done_tx);
258                Ok(())
259            }
260            .log_err()
261        });
262
263        Self {
264            server_id,
265            notification_handlers,
266            response_handlers,
267            name: Default::default(),
268            capabilities: Default::default(),
269            next_id: Default::default(),
270            outbound_tx,
271            executor: cx.background(),
272            io_tasks: Mutex::new(Some((input_task, output_task))),
273            output_done_rx: Mutex::new(Some(output_done_rx)),
274            root_path: root_path.to_path_buf(),
275            _server: server,
276        }
277    }
278
279    /// Initializes a language server.
280    /// Note that `options` is used directly to construct [`InitializeParams`],
281    /// which is why it is owned.
282    pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
283        let root_uri = Url::from_file_path(&self.root_path).unwrap();
284        #[allow(deprecated)]
285        let params = InitializeParams {
286            process_id: Default::default(),
287            root_path: Default::default(),
288            root_uri: Some(root_uri.clone()),
289            initialization_options: options,
290            capabilities: ClientCapabilities {
291                workspace: Some(WorkspaceClientCapabilities {
292                    configuration: Some(true),
293                    did_change_configuration: Some(DynamicRegistrationClientCapabilities {
294                        dynamic_registration: Some(true),
295                    }),
296                    ..Default::default()
297                }),
298                text_document: Some(TextDocumentClientCapabilities {
299                    definition: Some(GotoCapability {
300                        link_support: Some(true),
301                        ..Default::default()
302                    }),
303                    code_action: Some(CodeActionClientCapabilities {
304                        code_action_literal_support: Some(CodeActionLiteralSupport {
305                            code_action_kind: CodeActionKindLiteralSupport {
306                                value_set: vec![
307                                    CodeActionKind::REFACTOR.as_str().into(),
308                                    CodeActionKind::QUICKFIX.as_str().into(),
309                                    CodeActionKind::SOURCE.as_str().into(),
310                                ],
311                            },
312                        }),
313                        data_support: Some(true),
314                        resolve_support: Some(CodeActionCapabilityResolveSupport {
315                            properties: vec!["edit".to_string(), "command".to_string()],
316                        }),
317                        ..Default::default()
318                    }),
319                    completion: Some(CompletionClientCapabilities {
320                        completion_item: Some(CompletionItemCapability {
321                            snippet_support: Some(true),
322                            resolve_support: Some(CompletionItemCapabilityResolveSupport {
323                                properties: vec!["additionalTextEdits".to_string()],
324                            }),
325                            ..Default::default()
326                        }),
327                        ..Default::default()
328                    }),
329                    rename: Some(RenameClientCapabilities {
330                        prepare_support: Some(true),
331                        ..Default::default()
332                    }),
333                    hover: Some(HoverClientCapabilities {
334                        content_format: Some(vec![MarkupKind::Markdown]),
335                        ..Default::default()
336                    }),
337                    ..Default::default()
338                }),
339                experimental: Some(json!({
340                    "serverStatusNotification": true,
341                })),
342                window: Some(WindowClientCapabilities {
343                    work_done_progress: Some(true),
344                    ..Default::default()
345                }),
346                ..Default::default()
347            },
348            trace: Default::default(),
349            workspace_folders: Some(vec![WorkspaceFolder {
350                uri: root_uri,
351                name: Default::default(),
352            }]),
353            client_info: Default::default(),
354            locale: Default::default(),
355        };
356
357        let response = self.request::<request::Initialize>(params).await?;
358        if let Some(info) = response.server_info {
359            self.name = info.name;
360        }
361        self.capabilities = response.capabilities;
362
363        self.notify::<notification::Initialized>(InitializedParams {})?;
364        Ok(Arc::new(self))
365    }
366
367    pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
368        if let Some(tasks) = self.io_tasks.lock().take() {
369            let response_handlers = self.response_handlers.clone();
370            let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
371            let outbound_tx = self.outbound_tx.clone();
372            let mut output_done = self.output_done_rx.lock().take().unwrap();
373            let shutdown_request = Self::request_internal::<request::Shutdown>(
374                &next_id,
375                &response_handlers,
376                &outbound_tx,
377                (),
378            );
379            let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
380            outbound_tx.close();
381            Some(
382                async move {
383                    log::debug!("language server shutdown started");
384                    shutdown_request.await?;
385                    response_handlers.lock().take();
386                    exit?;
387                    output_done.recv().await;
388                    log::debug!("language server shutdown finished");
389                    drop(tasks);
390                    Ok(())
391                }
392                .log_err(),
393            )
394        } else {
395            None
396        }
397    }
398
399    #[must_use]
400    pub fn on_notification<T, F>(&self, f: F) -> Subscription
401    where
402        T: notification::Notification,
403        F: 'static + Send + FnMut(T::Params, AsyncAppContext),
404    {
405        self.on_custom_notification(T::METHOD, f)
406    }
407
408    #[must_use]
409    pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
410    where
411        T: request::Request,
412        T::Params: 'static + Send,
413        F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
414        Fut: 'static + Future<Output = Result<T::Result>>,
415    {
416        self.on_custom_request(T::METHOD, f)
417    }
418
419    pub fn remove_request_handler<T: request::Request>(&self) {
420        self.notification_handlers.lock().remove(T::METHOD);
421    }
422
423    #[must_use]
424    pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
425    where
426        F: 'static + Send + FnMut(Params, AsyncAppContext),
427        Params: DeserializeOwned,
428    {
429        let prev_handler = self.notification_handlers.lock().insert(
430            method,
431            Box::new(move |_, params, cx| {
432                if let Some(params) = serde_json::from_str(params).log_err() {
433                    f(params, cx);
434                }
435            }),
436        );
437        assert!(
438            prev_handler.is_none(),
439            "registered multiple handlers for the same LSP method"
440        );
441        Subscription {
442            method,
443            notification_handlers: self.notification_handlers.clone(),
444        }
445    }
446
447    #[must_use]
448    pub fn on_custom_request<Params, Res, Fut, F>(
449        &self,
450        method: &'static str,
451        mut f: F,
452    ) -> Subscription
453    where
454        F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
455        Fut: 'static + Future<Output = Result<Res>>,
456        Params: DeserializeOwned + Send + 'static,
457        Res: Serialize,
458    {
459        let outbound_tx = self.outbound_tx.clone();
460        let prev_handler = self.notification_handlers.lock().insert(
461            method,
462            Box::new(move |id, params, cx| {
463                if let Some(id) = id {
464                    if let Some(params) = serde_json::from_str(params).log_err() {
465                        let response = f(params, cx.clone());
466                        cx.foreground()
467                            .spawn({
468                                let outbound_tx = outbound_tx.clone();
469                                async move {
470                                    let response = match response.await {
471                                        Ok(result) => Response {
472                                            jsonrpc: JSON_RPC_VERSION,
473                                            id,
474                                            result: Some(result),
475                                            error: None,
476                                        },
477                                        Err(error) => Response {
478                                            jsonrpc: JSON_RPC_VERSION,
479                                            id,
480                                            result: None,
481                                            error: Some(Error {
482                                                message: error.to_string(),
483                                            }),
484                                        },
485                                    };
486                                    if let Some(response) = serde_json::to_vec(&response).log_err()
487                                    {
488                                        outbound_tx.try_send(response).ok();
489                                    }
490                                }
491                            })
492                            .detach();
493                    }
494                }
495            }),
496        );
497        assert!(
498            prev_handler.is_none(),
499            "registered multiple handlers for the same LSP method"
500        );
501        Subscription {
502            method,
503            notification_handlers: self.notification_handlers.clone(),
504        }
505    }
506
507    pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
508        &self.name
509    }
510
511    pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
512        &self.capabilities
513    }
514
515    pub fn server_id(&self) -> usize {
516        self.server_id
517    }
518
519    pub fn root_path(&self) -> &PathBuf {
520        &self.root_path
521    }
522
523    pub fn request<T: request::Request>(
524        &self,
525        params: T::Params,
526    ) -> impl Future<Output = Result<T::Result>>
527    where
528        T::Result: 'static + Send,
529    {
530        Self::request_internal::<T>(
531            &self.next_id,
532            &self.response_handlers,
533            &self.outbound_tx,
534            params,
535        )
536    }
537
538    fn request_internal<T: request::Request>(
539        next_id: &AtomicUsize,
540        response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
541        outbound_tx: &channel::Sender<Vec<u8>>,
542        params: T::Params,
543    ) -> impl 'static + Future<Output = Result<T::Result>>
544    where
545        T::Result: 'static + Send,
546    {
547        let id = next_id.fetch_add(1, SeqCst);
548        let message = serde_json::to_vec(&Request {
549            jsonrpc: JSON_RPC_VERSION,
550            id,
551            method: T::METHOD,
552            params,
553        })
554        .unwrap();
555
556        let (tx, rx) = oneshot::channel();
557        let handle_response = response_handlers
558            .lock()
559            .as_mut()
560            .ok_or_else(|| anyhow!("server shut down"))
561            .map(|handlers| {
562                handlers.insert(
563                    id,
564                    Box::new(move |result| {
565                        let response = match result {
566                            Ok(response) => serde_json::from_str(response)
567                                .context("failed to deserialize response"),
568                            Err(error) => Err(anyhow!("{}", error.message)),
569                        };
570                        let _ = tx.send(response);
571                    }),
572                );
573            });
574
575        let send = outbound_tx
576            .try_send(message)
577            .context("failed to write to language server's stdin");
578
579        async move {
580            handle_response?;
581            send?;
582            rx.await?
583        }
584    }
585
586    pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
587        Self::notify_internal::<T>(&self.outbound_tx, params)
588    }
589
590    fn notify_internal<T: notification::Notification>(
591        outbound_tx: &channel::Sender<Vec<u8>>,
592        params: T::Params,
593    ) -> Result<()> {
594        let message = serde_json::to_vec(&Notification {
595            jsonrpc: JSON_RPC_VERSION,
596            method: T::METHOD,
597            params,
598        })
599        .unwrap();
600        outbound_tx.try_send(message)?;
601        Ok(())
602    }
603}
604
605impl Drop for LanguageServer {
606    fn drop(&mut self) {
607        if let Some(shutdown) = self.shutdown() {
608            self.executor.spawn(shutdown).detach();
609        }
610    }
611}
612
613impl Subscription {
614    pub fn detach(mut self) {
615        self.method = "";
616    }
617}
618
619impl Drop for Subscription {
620    fn drop(&mut self) {
621        self.notification_handlers.lock().remove(self.method);
622    }
623}
624
625#[cfg(any(test, feature = "test-support"))]
626#[derive(Clone)]
627pub struct FakeLanguageServer {
628    pub server: Arc<LanguageServer>,
629    notifications_rx: channel::Receiver<(String, String)>,
630}
631
632#[cfg(any(test, feature = "test-support"))]
633impl LanguageServer {
634    pub fn full_capabilities() -> ServerCapabilities {
635        ServerCapabilities {
636            document_highlight_provider: Some(OneOf::Left(true)),
637            code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
638            document_formatting_provider: Some(OneOf::Left(true)),
639            document_range_formatting_provider: Some(OneOf::Left(true)),
640            ..Default::default()
641        }
642    }
643
644    pub fn fake(
645        name: String,
646        capabilities: ServerCapabilities,
647        cx: AsyncAppContext,
648    ) -> (Self, FakeLanguageServer) {
649        let (stdin_writer, stdin_reader) = async_pipe::pipe();
650        let (stdout_writer, stdout_reader) = async_pipe::pipe();
651        let (notifications_tx, notifications_rx) = channel::unbounded();
652
653        let server = Self::new_internal(
654            0,
655            stdin_writer,
656            stdout_reader,
657            None,
658            Path::new("/"),
659            cx.clone(),
660            |_| {},
661        );
662        let fake = FakeLanguageServer {
663            server: Arc::new(Self::new_internal(
664                0,
665                stdout_writer,
666                stdin_reader,
667                None,
668                Path::new("/"),
669                cx,
670                move |msg| {
671                    notifications_tx
672                        .try_send((msg.method.to_string(), msg.params.get().to_string()))
673                        .ok();
674                },
675            )),
676            notifications_rx,
677        };
678        fake.handle_request::<request::Initialize, _, _>({
679            let capabilities = capabilities;
680            move |_, _| {
681                let capabilities = capabilities.clone();
682                let name = name.clone();
683                async move {
684                    Ok(InitializeResult {
685                        capabilities,
686                        server_info: Some(ServerInfo {
687                            name,
688                            ..Default::default()
689                        }),
690                    })
691                }
692            }
693        });
694
695        (server, fake)
696    }
697}
698
699#[cfg(any(test, feature = "test-support"))]
700impl FakeLanguageServer {
701    pub fn notify<T: notification::Notification>(&self, params: T::Params) {
702        self.server.notify::<T>(params).ok();
703    }
704
705    pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
706    where
707        T: request::Request,
708        T::Result: 'static + Send,
709    {
710        self.server.request::<T>(params).await
711    }
712
713    pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
714        self.try_receive_notification::<T>().await.unwrap()
715    }
716
717    pub async fn try_receive_notification<T: notification::Notification>(
718        &mut self,
719    ) -> Option<T::Params> {
720        use futures::StreamExt as _;
721
722        loop {
723            let (method, params) = self.notifications_rx.next().await?;
724            if method == T::METHOD {
725                return Some(serde_json::from_str::<T::Params>(&params).unwrap());
726            } else {
727                log::info!("skipping message in fake language server {:?}", params);
728            }
729        }
730    }
731
732    pub fn handle_request<T, F, Fut>(
733        &self,
734        mut handler: F,
735    ) -> futures::channel::mpsc::UnboundedReceiver<()>
736    where
737        T: 'static + request::Request,
738        T::Params: 'static + Send,
739        F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
740        Fut: 'static + Send + Future<Output = Result<T::Result>>,
741    {
742        let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
743        self.server.remove_request_handler::<T>();
744        self.server
745            .on_request::<T, _, _>(move |params, cx| {
746                let result = handler(params, cx.clone());
747                let responded_tx = responded_tx.clone();
748                async move {
749                    cx.background().simulate_random_delay().await;
750                    let result = result.await;
751                    responded_tx.unbounded_send(()).ok();
752                    result
753                }
754            })
755            .detach();
756        responded_rx
757    }
758
759    pub fn remove_request_handler<T>(&mut self)
760    where
761        T: 'static + request::Request,
762    {
763        self.server.remove_request_handler::<T>();
764    }
765
766    pub async fn start_progress(&self, token: impl Into<String>) {
767        let token = token.into();
768        self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
769            token: NumberOrString::String(token.clone()),
770        })
771        .await
772        .unwrap();
773        self.notify::<notification::Progress>(ProgressParams {
774            token: NumberOrString::String(token),
775            value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
776        });
777    }
778
779    pub fn end_progress(&self, token: impl Into<String>) {
780        self.notify::<notification::Progress>(ProgressParams {
781            token: NumberOrString::String(token.into()),
782            value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
783        });
784    }
785}
786
787#[cfg(test)]
788mod tests {
789    use super::*;
790    use gpui::TestAppContext;
791
792    #[ctor::ctor]
793    fn init_logger() {
794        if std::env::var("RUST_LOG").is_ok() {
795            env_logger::init();
796        }
797    }
798
799    #[gpui::test]
800    async fn test_fake(cx: &mut TestAppContext) {
801        let (server, mut fake) =
802            LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
803
804        let (message_tx, message_rx) = channel::unbounded();
805        let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
806        server
807            .on_notification::<notification::ShowMessage, _>(move |params, _| {
808                message_tx.try_send(params).unwrap()
809            })
810            .detach();
811        server
812            .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
813                diagnostics_tx.try_send(params).unwrap()
814            })
815            .detach();
816
817        let server = server.initialize(None).await.unwrap();
818        server
819            .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
820                text_document: TextDocumentItem::new(
821                    Url::from_str("file://a/b").unwrap(),
822                    "rust".to_string(),
823                    0,
824                    "".to_string(),
825                ),
826            })
827            .unwrap();
828        assert_eq!(
829            fake.receive_notification::<notification::DidOpenTextDocument>()
830                .await
831                .text_document
832                .uri
833                .as_str(),
834            "file://a/b"
835        );
836
837        fake.notify::<notification::ShowMessage>(ShowMessageParams {
838            typ: MessageType::ERROR,
839            message: "ok".to_string(),
840        });
841        fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
842            uri: Url::from_str("file://b/c").unwrap(),
843            version: Some(5),
844            diagnostics: vec![],
845        });
846        assert_eq!(message_rx.recv().await.unwrap().message, "ok");
847        assert_eq!(
848            diagnostics_rx.recv().await.unwrap().uri.as_str(),
849            "file://b/c"
850        );
851
852        fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
853
854        drop(server);
855        fake.receive_notification::<notification::Exit>().await;
856    }
857}