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 code_action_kinds: Option<Vec<CodeActionKind>>,
44 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
45 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
46 executor: Arc<executor::Background>,
47 #[allow(clippy::type_complexity)]
48 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
49 output_done_rx: Mutex<Option<barrier::Receiver>>,
50 root_path: PathBuf,
51 _server: Option<Child>,
52}
53
54pub struct Subscription {
55 method: &'static str,
56 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
57}
58
59#[derive(Serialize, Deserialize)]
60struct Request<'a, T> {
61 jsonrpc: &'static str,
62 id: usize,
63 method: &'a str,
64 params: T,
65}
66
67#[derive(Serialize, Deserialize)]
68struct AnyResponse<'a> {
69 jsonrpc: &'a str,
70 id: usize,
71 #[serde(default)]
72 error: Option<Error>,
73 #[serde(borrow)]
74 result: Option<&'a RawValue>,
75}
76
77#[derive(Serialize)]
78struct Response<T> {
79 jsonrpc: &'static str,
80 id: usize,
81 result: Option<T>,
82 error: Option<Error>,
83}
84
85#[derive(Serialize, Deserialize)]
86struct Notification<'a, T> {
87 jsonrpc: &'static str,
88 #[serde(borrow)]
89 method: &'a str,
90 params: T,
91}
92
93#[derive(Deserialize)]
94struct AnyNotification<'a> {
95 #[serde(default)]
96 id: Option<usize>,
97 #[serde(borrow)]
98 method: &'a str,
99 #[serde(borrow)]
100 params: &'a RawValue,
101}
102
103#[derive(Debug, Serialize, Deserialize)]
104struct Error {
105 message: String,
106}
107
108impl LanguageServer {
109 pub fn new<T: AsRef<std::ffi::OsStr>>(
110 server_id: usize,
111 binary_path: &Path,
112 arguments: &[T],
113 root_path: &Path,
114 code_action_kinds: Option<Vec<CodeActionKind>>,
115 cx: AsyncAppContext,
116 ) -> Result<Self> {
117 let working_dir = if root_path.is_dir() {
118 root_path
119 } else {
120 root_path.parent().unwrap_or_else(|| Path::new("/"))
121 };
122
123 let mut server = process::Command::new(binary_path)
124 .current_dir(working_dir)
125 .args(arguments)
126 .stdin(Stdio::piped())
127 .stdout(Stdio::piped())
128 .stderr(Stdio::inherit())
129 .kill_on_drop(true)
130 .spawn()?;
131
132 let stdin = server.stdin.take().unwrap();
133 let stout = server.stdout.take().unwrap();
134 let mut server = Self::new_internal(
135 server_id,
136 stdin,
137 stout,
138 Some(server),
139 root_path,
140 code_action_kinds,
141 cx,
142 |notification| {
143 log::info!(
144 "unhandled notification {}:\n{}",
145 notification.method,
146 serde_json::to_string_pretty(
147 &Value::from_str(notification.params.get()).unwrap()
148 )
149 .unwrap()
150 );
151 },
152 );
153
154 if let Some(name) = binary_path.file_name() {
155 server.name = name.to_string_lossy().to_string();
156 }
157 Ok(server)
158 }
159
160 fn new_internal<Stdin, Stdout, F>(
161 server_id: usize,
162 stdin: Stdin,
163 stdout: Stdout,
164 server: Option<Child>,
165 root_path: &Path,
166 code_action_kinds: Option<Vec<CodeActionKind>>,
167 cx: AsyncAppContext,
168 on_unhandled_notification: F,
169 ) -> Self
170 where
171 Stdin: AsyncWrite + Unpin + Send + 'static,
172 Stdout: AsyncRead + Unpin + Send + 'static,
173 F: FnMut(AnyNotification) + 'static + Send,
174 {
175 let (outbound_tx, outbound_rx) = channel::unbounded::<Vec<u8>>();
176 let notification_handlers =
177 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
178 let response_handlers =
179 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
180 let input_task = cx.spawn(|cx| {
181 let notification_handlers = notification_handlers.clone();
182 let response_handlers = response_handlers.clone();
183 Self::handle_input(
184 stdout,
185 on_unhandled_notification,
186 notification_handlers,
187 response_handlers,
188 cx,
189 )
190 .log_err()
191 });
192 let (output_done_tx, output_done_rx) = barrier::channel();
193 let output_task = cx.background().spawn({
194 let response_handlers = response_handlers.clone();
195 Self::handle_output(stdin, outbound_rx, output_done_tx, response_handlers).log_err()
196 });
197
198 Self {
199 server_id,
200 notification_handlers,
201 response_handlers,
202 name: Default::default(),
203 capabilities: Default::default(),
204 code_action_kinds,
205 next_id: Default::default(),
206 outbound_tx,
207 executor: cx.background(),
208 io_tasks: Mutex::new(Some((input_task, output_task))),
209 output_done_rx: Mutex::new(Some(output_done_rx)),
210 root_path: root_path.to_path_buf(),
211 _server: server,
212 }
213 }
214
215 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
216 self.code_action_kinds.clone()
217 }
218
219 async fn handle_input<Stdout, F>(
220 stdout: Stdout,
221 mut on_unhandled_notification: F,
222 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
223 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
224 cx: AsyncAppContext,
225 ) -> anyhow::Result<()>
226 where
227 Stdout: AsyncRead + Unpin + Send + 'static,
228 F: FnMut(AnyNotification) + 'static + Send,
229 {
230 let mut stdout = BufReader::new(stdout);
231 let _clear_response_handlers = util::defer({
232 let response_handlers = response_handlers.clone();
233 move || {
234 response_handlers.lock().take();
235 }
236 });
237 let mut buffer = Vec::new();
238 loop {
239 buffer.clear();
240 stdout.read_until(b'\n', &mut buffer).await?;
241 stdout.read_until(b'\n', &mut buffer).await?;
242 let message_len: usize = std::str::from_utf8(&buffer)?
243 .strip_prefix(CONTENT_LEN_HEADER)
244 .ok_or_else(|| anyhow!("invalid header"))?
245 .trim_end()
246 .parse()?;
247
248 buffer.resize(message_len, 0);
249 stdout.read_exact(&mut buffer).await?;
250 log::trace!("incoming message:{}", String::from_utf8_lossy(&buffer));
251
252 if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
253 if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
254 handler(msg.id, msg.params.get(), cx.clone());
255 } else {
256 on_unhandled_notification(msg);
257 }
258 } else if let Ok(AnyResponse {
259 id, error, result, ..
260 }) = serde_json::from_slice(&buffer)
261 {
262 if let Some(handler) = response_handlers
263 .lock()
264 .as_mut()
265 .and_then(|handlers| handlers.remove(&id))
266 {
267 if let Some(error) = error {
268 handler(Err(error));
269 } else if let Some(result) = result {
270 handler(Ok(result.get()));
271 } else {
272 handler(Ok("null"));
273 }
274 }
275 } else {
276 warn!(
277 "Failed to deserialize message:\n{}",
278 std::str::from_utf8(&buffer)?
279 );
280 }
281
282 // Don't starve the main thread when receiving lots of messages at once.
283 smol::future::yield_now().await;
284 }
285 }
286
287 async fn handle_output<Stdin>(
288 stdin: Stdin,
289 outbound_rx: channel::Receiver<Vec<u8>>,
290 output_done_tx: barrier::Sender,
291 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
292 ) -> anyhow::Result<()>
293 where
294 Stdin: AsyncWrite + Unpin + Send + 'static,
295 {
296 let mut stdin = BufWriter::new(stdin);
297 let _clear_response_handlers = util::defer({
298 let response_handlers = response_handlers.clone();
299 move || {
300 response_handlers.lock().take();
301 }
302 });
303 let mut content_len_buffer = Vec::new();
304 while let Ok(message) = outbound_rx.recv().await {
305 log::trace!("outgoing message:{}", String::from_utf8_lossy(&message));
306 content_len_buffer.clear();
307 write!(content_len_buffer, "{}", message.len()).unwrap();
308 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
309 stdin.write_all(&content_len_buffer).await?;
310 stdin.write_all("\r\n\r\n".as_bytes()).await?;
311 stdin.write_all(&message).await?;
312 stdin.flush().await?;
313 }
314 drop(output_done_tx);
315 Ok(())
316 }
317
318 /// Initializes a language server.
319 /// Note that `options` is used directly to construct [`InitializeParams`],
320 /// which is why it is owned.
321 pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
322 let root_uri = Url::from_file_path(&self.root_path).unwrap();
323 #[allow(deprecated)]
324 let params = InitializeParams {
325 process_id: Default::default(),
326 root_path: Default::default(),
327 root_uri: Some(root_uri.clone()),
328 initialization_options: options,
329 capabilities: ClientCapabilities {
330 workspace: Some(WorkspaceClientCapabilities {
331 configuration: Some(true),
332 did_change_watched_files: Some(DynamicRegistrationClientCapabilities {
333 dynamic_registration: Some(true),
334 }),
335 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
336 dynamic_registration: Some(true),
337 }),
338 ..Default::default()
339 }),
340 text_document: Some(TextDocumentClientCapabilities {
341 definition: Some(GotoCapability {
342 link_support: Some(true),
343 ..Default::default()
344 }),
345 code_action: Some(CodeActionClientCapabilities {
346 code_action_literal_support: Some(CodeActionLiteralSupport {
347 code_action_kind: CodeActionKindLiteralSupport {
348 value_set: vec![
349 CodeActionKind::REFACTOR.as_str().into(),
350 CodeActionKind::QUICKFIX.as_str().into(),
351 CodeActionKind::SOURCE.as_str().into(),
352 ],
353 },
354 }),
355 data_support: Some(true),
356 resolve_support: Some(CodeActionCapabilityResolveSupport {
357 properties: vec!["edit".to_string(), "command".to_string()],
358 }),
359 ..Default::default()
360 }),
361 completion: Some(CompletionClientCapabilities {
362 completion_item: Some(CompletionItemCapability {
363 snippet_support: Some(true),
364 resolve_support: Some(CompletionItemCapabilityResolveSupport {
365 properties: vec!["additionalTextEdits".to_string()],
366 }),
367 ..Default::default()
368 }),
369 ..Default::default()
370 }),
371 rename: Some(RenameClientCapabilities {
372 prepare_support: Some(true),
373 ..Default::default()
374 }),
375 hover: Some(HoverClientCapabilities {
376 content_format: Some(vec![MarkupKind::Markdown]),
377 ..Default::default()
378 }),
379 ..Default::default()
380 }),
381 experimental: Some(json!({
382 "serverStatusNotification": true,
383 })),
384 window: Some(WindowClientCapabilities {
385 work_done_progress: Some(true),
386 ..Default::default()
387 }),
388 ..Default::default()
389 },
390 trace: Default::default(),
391 workspace_folders: Some(vec![WorkspaceFolder {
392 uri: root_uri,
393 name: Default::default(),
394 }]),
395 client_info: Default::default(),
396 locale: Default::default(),
397 };
398
399 let response = self.request::<request::Initialize>(params).await?;
400 if let Some(info) = response.server_info {
401 self.name = info.name;
402 }
403 self.capabilities = response.capabilities;
404
405 self.notify::<notification::Initialized>(InitializedParams {})?;
406 Ok(Arc::new(self))
407 }
408
409 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
410 if let Some(tasks) = self.io_tasks.lock().take() {
411 let response_handlers = self.response_handlers.clone();
412 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
413 let outbound_tx = self.outbound_tx.clone();
414 let mut output_done = self.output_done_rx.lock().take().unwrap();
415 let shutdown_request = Self::request_internal::<request::Shutdown>(
416 &next_id,
417 &response_handlers,
418 &outbound_tx,
419 (),
420 );
421 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
422 outbound_tx.close();
423 Some(
424 async move {
425 log::debug!("language server shutdown started");
426 shutdown_request.await?;
427 response_handlers.lock().take();
428 exit?;
429 output_done.recv().await;
430 log::debug!("language server shutdown finished");
431 drop(tasks);
432 anyhow::Ok(())
433 }
434 .log_err(),
435 )
436 } else {
437 None
438 }
439 }
440
441 #[must_use]
442 pub fn on_notification<T, F>(&self, f: F) -> Subscription
443 where
444 T: notification::Notification,
445 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
446 {
447 self.on_custom_notification(T::METHOD, f)
448 }
449
450 #[must_use]
451 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
452 where
453 T: request::Request,
454 T::Params: 'static + Send,
455 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
456 Fut: 'static + Future<Output = Result<T::Result>>,
457 {
458 self.on_custom_request(T::METHOD, f)
459 }
460
461 pub fn remove_request_handler<T: request::Request>(&self) {
462 self.notification_handlers.lock().remove(T::METHOD);
463 }
464
465 pub fn remove_notification_handler<T: notification::Notification>(&self) {
466 self.notification_handlers.lock().remove(T::METHOD);
467 }
468
469 #[must_use]
470 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
471 where
472 F: 'static + Send + FnMut(Params, AsyncAppContext),
473 Params: DeserializeOwned,
474 {
475 let prev_handler = self.notification_handlers.lock().insert(
476 method,
477 Box::new(move |_, params, cx| {
478 if let Some(params) = serde_json::from_str(params).log_err() {
479 f(params, cx);
480 }
481 }),
482 );
483 assert!(
484 prev_handler.is_none(),
485 "registered multiple handlers for the same LSP method"
486 );
487 Subscription {
488 method,
489 notification_handlers: self.notification_handlers.clone(),
490 }
491 }
492
493 #[must_use]
494 pub fn on_custom_request<Params, Res, Fut, F>(
495 &self,
496 method: &'static str,
497 mut f: F,
498 ) -> Subscription
499 where
500 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
501 Fut: 'static + Future<Output = Result<Res>>,
502 Params: DeserializeOwned + Send + 'static,
503 Res: Serialize,
504 {
505 let outbound_tx = self.outbound_tx.clone();
506 let prev_handler = self.notification_handlers.lock().insert(
507 method,
508 Box::new(move |id, params, cx| {
509 if let Some(id) = id {
510 match serde_json::from_str(params) {
511 Ok(params) => {
512 let response = f(params, cx.clone());
513 cx.foreground()
514 .spawn({
515 let outbound_tx = outbound_tx.clone();
516 async move {
517 let response = match response.await {
518 Ok(result) => Response {
519 jsonrpc: JSON_RPC_VERSION,
520 id,
521 result: Some(result),
522 error: None,
523 },
524 Err(error) => Response {
525 jsonrpc: JSON_RPC_VERSION,
526 id,
527 result: None,
528 error: Some(Error {
529 message: error.to_string(),
530 }),
531 },
532 };
533 if let Some(response) =
534 serde_json::to_vec(&response).log_err()
535 {
536 outbound_tx.try_send(response).ok();
537 }
538 }
539 })
540 .detach();
541 }
542 Err(error) => {
543 log::error!(
544 "error deserializing {} request: {:?}, message: {:?}",
545 method,
546 error,
547 params
548 );
549 let response = AnyResponse {
550 jsonrpc: JSON_RPC_VERSION,
551 id,
552 result: None,
553 error: Some(Error {
554 message: error.to_string(),
555 }),
556 };
557 if let Some(response) = serde_json::to_vec(&response).log_err() {
558 outbound_tx.try_send(response).ok();
559 }
560 }
561 }
562 }
563 }),
564 );
565 assert!(
566 prev_handler.is_none(),
567 "registered multiple handlers for the same LSP method"
568 );
569 Subscription {
570 method,
571 notification_handlers: self.notification_handlers.clone(),
572 }
573 }
574
575 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
576 &self.name
577 }
578
579 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
580 &self.capabilities
581 }
582
583 pub fn server_id(&self) -> usize {
584 self.server_id
585 }
586
587 pub fn root_path(&self) -> &PathBuf {
588 &self.root_path
589 }
590
591 pub fn request<T: request::Request>(
592 &self,
593 params: T::Params,
594 ) -> impl Future<Output = Result<T::Result>>
595 where
596 T::Result: 'static + Send,
597 {
598 Self::request_internal::<T>(
599 &self.next_id,
600 &self.response_handlers,
601 &self.outbound_tx,
602 params,
603 )
604 }
605
606 fn request_internal<T: request::Request>(
607 next_id: &AtomicUsize,
608 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
609 outbound_tx: &channel::Sender<Vec<u8>>,
610 params: T::Params,
611 ) -> impl 'static + Future<Output = Result<T::Result>>
612 where
613 T::Result: 'static + Send,
614 {
615 let id = next_id.fetch_add(1, SeqCst);
616 let message = serde_json::to_vec(&Request {
617 jsonrpc: JSON_RPC_VERSION,
618 id,
619 method: T::METHOD,
620 params,
621 })
622 .unwrap();
623
624 let (tx, rx) = oneshot::channel();
625 let handle_response = response_handlers
626 .lock()
627 .as_mut()
628 .ok_or_else(|| anyhow!("server shut down"))
629 .map(|handlers| {
630 handlers.insert(
631 id,
632 Box::new(move |result| {
633 let response = match result {
634 Ok(response) => serde_json::from_str(response)
635 .context("failed to deserialize response"),
636 Err(error) => Err(anyhow!("{}", error.message)),
637 };
638 let _ = tx.send(response);
639 }),
640 );
641 });
642
643 let send = outbound_tx
644 .try_send(message)
645 .context("failed to write to language server's stdin");
646
647 async move {
648 handle_response?;
649 send?;
650 rx.await?
651 }
652 }
653
654 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
655 Self::notify_internal::<T>(&self.outbound_tx, params)
656 }
657
658 fn notify_internal<T: notification::Notification>(
659 outbound_tx: &channel::Sender<Vec<u8>>,
660 params: T::Params,
661 ) -> Result<()> {
662 let message = serde_json::to_vec(&Notification {
663 jsonrpc: JSON_RPC_VERSION,
664 method: T::METHOD,
665 params,
666 })
667 .unwrap();
668 outbound_tx.try_send(message)?;
669 Ok(())
670 }
671}
672
673impl Drop for LanguageServer {
674 fn drop(&mut self) {
675 if let Some(shutdown) = self.shutdown() {
676 self.executor.spawn(shutdown).detach();
677 }
678 }
679}
680
681impl Subscription {
682 pub fn detach(mut self) {
683 self.method = "";
684 }
685}
686
687impl Drop for Subscription {
688 fn drop(&mut self) {
689 self.notification_handlers.lock().remove(self.method);
690 }
691}
692
693#[cfg(any(test, feature = "test-support"))]
694#[derive(Clone)]
695pub struct FakeLanguageServer {
696 pub server: Arc<LanguageServer>,
697 notifications_rx: channel::Receiver<(String, String)>,
698}
699
700#[cfg(any(test, feature = "test-support"))]
701impl LanguageServer {
702 pub fn full_capabilities() -> ServerCapabilities {
703 ServerCapabilities {
704 document_highlight_provider: Some(OneOf::Left(true)),
705 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
706 document_formatting_provider: Some(OneOf::Left(true)),
707 document_range_formatting_provider: Some(OneOf::Left(true)),
708 ..Default::default()
709 }
710 }
711
712 pub fn fake(
713 name: String,
714 capabilities: ServerCapabilities,
715 cx: AsyncAppContext,
716 ) -> (Self, FakeLanguageServer) {
717 let (stdin_writer, stdin_reader) = async_pipe::pipe();
718 let (stdout_writer, stdout_reader) = async_pipe::pipe();
719 let (notifications_tx, notifications_rx) = channel::unbounded();
720
721 let server = Self::new_internal(
722 0,
723 stdin_writer,
724 stdout_reader,
725 None,
726 Path::new("/"),
727 None,
728 cx.clone(),
729 |_| {},
730 );
731 let fake = FakeLanguageServer {
732 server: Arc::new(Self::new_internal(
733 0,
734 stdout_writer,
735 stdin_reader,
736 None,
737 Path::new("/"),
738 None,
739 cx,
740 move |msg| {
741 notifications_tx
742 .try_send((msg.method.to_string(), msg.params.get().to_string()))
743 .ok();
744 },
745 )),
746 notifications_rx,
747 };
748 fake.handle_request::<request::Initialize, _, _>({
749 let capabilities = capabilities;
750 move |_, _| {
751 let capabilities = capabilities.clone();
752 let name = name.clone();
753 async move {
754 Ok(InitializeResult {
755 capabilities,
756 server_info: Some(ServerInfo {
757 name,
758 ..Default::default()
759 }),
760 })
761 }
762 }
763 });
764
765 (server, fake)
766 }
767}
768
769#[cfg(any(test, feature = "test-support"))]
770impl FakeLanguageServer {
771 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
772 self.server.notify::<T>(params).ok();
773 }
774
775 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
776 where
777 T: request::Request,
778 T::Result: 'static + Send,
779 {
780 self.server.request::<T>(params).await
781 }
782
783 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
784 self.try_receive_notification::<T>().await.unwrap()
785 }
786
787 pub async fn try_receive_notification<T: notification::Notification>(
788 &mut self,
789 ) -> Option<T::Params> {
790 use futures::StreamExt as _;
791
792 loop {
793 let (method, params) = self.notifications_rx.next().await?;
794 if method == T::METHOD {
795 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
796 } else {
797 log::info!("skipping message in fake language server {:?}", params);
798 }
799 }
800 }
801
802 pub fn handle_request<T, F, Fut>(
803 &self,
804 mut handler: F,
805 ) -> futures::channel::mpsc::UnboundedReceiver<()>
806 where
807 T: 'static + request::Request,
808 T::Params: 'static + Send,
809 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
810 Fut: 'static + Send + Future<Output = Result<T::Result>>,
811 {
812 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
813 self.server.remove_request_handler::<T>();
814 self.server
815 .on_request::<T, _, _>(move |params, cx| {
816 let result = handler(params, cx.clone());
817 let responded_tx = responded_tx.clone();
818 async move {
819 cx.background().simulate_random_delay().await;
820 let result = result.await;
821 responded_tx.unbounded_send(()).ok();
822 result
823 }
824 })
825 .detach();
826 responded_rx
827 }
828
829 pub fn handle_notification<T, F>(
830 &self,
831 mut handler: F,
832 ) -> futures::channel::mpsc::UnboundedReceiver<()>
833 where
834 T: 'static + notification::Notification,
835 T::Params: 'static + Send,
836 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
837 {
838 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
839 self.server.remove_notification_handler::<T>();
840 self.server
841 .on_notification::<T, _>(move |params, cx| {
842 handler(params, cx.clone());
843 handled_tx.unbounded_send(()).ok();
844 })
845 .detach();
846 handled_rx
847 }
848
849 pub fn remove_request_handler<T>(&mut self)
850 where
851 T: 'static + request::Request,
852 {
853 self.server.remove_request_handler::<T>();
854 }
855
856 pub async fn start_progress(&self, token: impl Into<String>) {
857 let token = token.into();
858 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
859 token: NumberOrString::String(token.clone()),
860 })
861 .await
862 .unwrap();
863 self.notify::<notification::Progress>(ProgressParams {
864 token: NumberOrString::String(token),
865 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
866 });
867 }
868
869 pub fn end_progress(&self, token: impl Into<String>) {
870 self.notify::<notification::Progress>(ProgressParams {
871 token: NumberOrString::String(token.into()),
872 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
873 });
874 }
875}
876
877#[cfg(test)]
878mod tests {
879 use super::*;
880 use gpui::TestAppContext;
881
882 #[ctor::ctor]
883 fn init_logger() {
884 if std::env::var("RUST_LOG").is_ok() {
885 env_logger::init();
886 }
887 }
888
889 #[gpui::test]
890 async fn test_fake(cx: &mut TestAppContext) {
891 let (server, mut fake) =
892 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
893
894 let (message_tx, message_rx) = channel::unbounded();
895 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
896 server
897 .on_notification::<notification::ShowMessage, _>(move |params, _| {
898 message_tx.try_send(params).unwrap()
899 })
900 .detach();
901 server
902 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
903 diagnostics_tx.try_send(params).unwrap()
904 })
905 .detach();
906
907 let server = server.initialize(None).await.unwrap();
908 server
909 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
910 text_document: TextDocumentItem::new(
911 Url::from_str("file://a/b").unwrap(),
912 "rust".to_string(),
913 0,
914 "".to_string(),
915 ),
916 })
917 .unwrap();
918 assert_eq!(
919 fake.receive_notification::<notification::DidOpenTextDocument>()
920 .await
921 .text_document
922 .uri
923 .as_str(),
924 "file://a/b"
925 );
926
927 fake.notify::<notification::ShowMessage>(ShowMessageParams {
928 typ: MessageType::ERROR,
929 message: "ok".to_string(),
930 });
931 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
932 uri: Url::from_str("file://b/c").unwrap(),
933 version: Some(5),
934 diagnostics: vec![],
935 });
936 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
937 assert_eq!(
938 diagnostics_rx.recv().await.unwrap().uri.as_str(),
939 "file://b/c"
940 );
941
942 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
943
944 drop(server);
945 fake.receive_notification::<notification::Exit>().await;
946 }
947}