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 workspace_folders: Some(true),
339 ..Default::default()
340 }),
341 text_document: Some(TextDocumentClientCapabilities {
342 definition: Some(GotoCapability {
343 link_support: Some(true),
344 ..Default::default()
345 }),
346 code_action: Some(CodeActionClientCapabilities {
347 code_action_literal_support: Some(CodeActionLiteralSupport {
348 code_action_kind: CodeActionKindLiteralSupport {
349 value_set: vec![
350 CodeActionKind::REFACTOR.as_str().into(),
351 CodeActionKind::QUICKFIX.as_str().into(),
352 CodeActionKind::SOURCE.as_str().into(),
353 ],
354 },
355 }),
356 data_support: Some(true),
357 resolve_support: Some(CodeActionCapabilityResolveSupport {
358 properties: vec!["edit".to_string(), "command".to_string()],
359 }),
360 ..Default::default()
361 }),
362 completion: Some(CompletionClientCapabilities {
363 completion_item: Some(CompletionItemCapability {
364 snippet_support: Some(true),
365 resolve_support: Some(CompletionItemCapabilityResolveSupport {
366 properties: vec!["additionalTextEdits".to_string()],
367 }),
368 ..Default::default()
369 }),
370 ..Default::default()
371 }),
372 rename: Some(RenameClientCapabilities {
373 prepare_support: Some(true),
374 ..Default::default()
375 }),
376 hover: Some(HoverClientCapabilities {
377 content_format: Some(vec![MarkupKind::Markdown]),
378 ..Default::default()
379 }),
380 ..Default::default()
381 }),
382 experimental: Some(json!({
383 "serverStatusNotification": true,
384 })),
385 window: Some(WindowClientCapabilities {
386 work_done_progress: Some(true),
387 ..Default::default()
388 }),
389 ..Default::default()
390 },
391 trace: Default::default(),
392 workspace_folders: Some(vec![WorkspaceFolder {
393 uri: root_uri,
394 name: Default::default(),
395 }]),
396 client_info: Default::default(),
397 locale: Default::default(),
398 };
399
400 let response = self.request::<request::Initialize>(params).await?;
401 if let Some(info) = response.server_info {
402 self.name = info.name;
403 }
404 self.capabilities = response.capabilities;
405
406 self.notify::<notification::Initialized>(InitializedParams {})?;
407 Ok(Arc::new(self))
408 }
409
410 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
411 if let Some(tasks) = self.io_tasks.lock().take() {
412 let response_handlers = self.response_handlers.clone();
413 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
414 let outbound_tx = self.outbound_tx.clone();
415 let mut output_done = self.output_done_rx.lock().take().unwrap();
416 let shutdown_request = Self::request_internal::<request::Shutdown>(
417 &next_id,
418 &response_handlers,
419 &outbound_tx,
420 (),
421 );
422 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
423 outbound_tx.close();
424 Some(
425 async move {
426 log::debug!("language server shutdown started");
427 shutdown_request.await?;
428 response_handlers.lock().take();
429 exit?;
430 output_done.recv().await;
431 log::debug!("language server shutdown finished");
432 drop(tasks);
433 anyhow::Ok(())
434 }
435 .log_err(),
436 )
437 } else {
438 None
439 }
440 }
441
442 #[must_use]
443 pub fn on_notification<T, F>(&self, f: F) -> Subscription
444 where
445 T: notification::Notification,
446 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
447 {
448 self.on_custom_notification(T::METHOD, f)
449 }
450
451 #[must_use]
452 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
453 where
454 T: request::Request,
455 T::Params: 'static + Send,
456 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
457 Fut: 'static + Future<Output = Result<T::Result>>,
458 {
459 self.on_custom_request(T::METHOD, f)
460 }
461
462 pub fn remove_request_handler<T: request::Request>(&self) {
463 self.notification_handlers.lock().remove(T::METHOD);
464 }
465
466 pub fn remove_notification_handler<T: notification::Notification>(&self) {
467 self.notification_handlers.lock().remove(T::METHOD);
468 }
469
470 #[must_use]
471 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
472 where
473 F: 'static + Send + FnMut(Params, AsyncAppContext),
474 Params: DeserializeOwned,
475 {
476 let prev_handler = self.notification_handlers.lock().insert(
477 method,
478 Box::new(move |_, params, cx| {
479 if let Some(params) = serde_json::from_str(params).log_err() {
480 f(params, cx);
481 }
482 }),
483 );
484 assert!(
485 prev_handler.is_none(),
486 "registered multiple handlers for the same LSP method"
487 );
488 Subscription {
489 method,
490 notification_handlers: self.notification_handlers.clone(),
491 }
492 }
493
494 #[must_use]
495 pub fn on_custom_request<Params, Res, Fut, F>(
496 &self,
497 method: &'static str,
498 mut f: F,
499 ) -> Subscription
500 where
501 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
502 Fut: 'static + Future<Output = Result<Res>>,
503 Params: DeserializeOwned + Send + 'static,
504 Res: Serialize,
505 {
506 let outbound_tx = self.outbound_tx.clone();
507 let prev_handler = self.notification_handlers.lock().insert(
508 method,
509 Box::new(move |id, params, cx| {
510 if let Some(id) = id {
511 match serde_json::from_str(params) {
512 Ok(params) => {
513 let response = f(params, cx.clone());
514 cx.foreground()
515 .spawn({
516 let outbound_tx = outbound_tx.clone();
517 async move {
518 let response = match response.await {
519 Ok(result) => Response {
520 jsonrpc: JSON_RPC_VERSION,
521 id,
522 result: Some(result),
523 error: None,
524 },
525 Err(error) => Response {
526 jsonrpc: JSON_RPC_VERSION,
527 id,
528 result: None,
529 error: Some(Error {
530 message: error.to_string(),
531 }),
532 },
533 };
534 if let Some(response) =
535 serde_json::to_vec(&response).log_err()
536 {
537 outbound_tx.try_send(response).ok();
538 }
539 }
540 })
541 .detach();
542 }
543 Err(error) => {
544 log::error!(
545 "error deserializing {} request: {:?}, message: {:?}",
546 method,
547 error,
548 params
549 );
550 let response = AnyResponse {
551 jsonrpc: JSON_RPC_VERSION,
552 id,
553 result: None,
554 error: Some(Error {
555 message: error.to_string(),
556 }),
557 };
558 if let Some(response) = serde_json::to_vec(&response).log_err() {
559 outbound_tx.try_send(response).ok();
560 }
561 }
562 }
563 }
564 }),
565 );
566 assert!(
567 prev_handler.is_none(),
568 "registered multiple handlers for the same LSP method"
569 );
570 Subscription {
571 method,
572 notification_handlers: self.notification_handlers.clone(),
573 }
574 }
575
576 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
577 &self.name
578 }
579
580 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
581 &self.capabilities
582 }
583
584 pub fn server_id(&self) -> usize {
585 self.server_id
586 }
587
588 pub fn root_path(&self) -> &PathBuf {
589 &self.root_path
590 }
591
592 pub fn request<T: request::Request>(
593 &self,
594 params: T::Params,
595 ) -> impl Future<Output = Result<T::Result>>
596 where
597 T::Result: 'static + Send,
598 {
599 Self::request_internal::<T>(
600 &self.next_id,
601 &self.response_handlers,
602 &self.outbound_tx,
603 params,
604 )
605 }
606
607 fn request_internal<T: request::Request>(
608 next_id: &AtomicUsize,
609 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
610 outbound_tx: &channel::Sender<Vec<u8>>,
611 params: T::Params,
612 ) -> impl 'static + Future<Output = Result<T::Result>>
613 where
614 T::Result: 'static + Send,
615 {
616 let id = next_id.fetch_add(1, SeqCst);
617 let message = serde_json::to_vec(&Request {
618 jsonrpc: JSON_RPC_VERSION,
619 id,
620 method: T::METHOD,
621 params,
622 })
623 .unwrap();
624
625 let (tx, rx) = oneshot::channel();
626 let handle_response = response_handlers
627 .lock()
628 .as_mut()
629 .ok_or_else(|| anyhow!("server shut down"))
630 .map(|handlers| {
631 handlers.insert(
632 id,
633 Box::new(move |result| {
634 let response = match result {
635 Ok(response) => serde_json::from_str(response)
636 .context("failed to deserialize response"),
637 Err(error) => Err(anyhow!("{}", error.message)),
638 };
639 let _ = tx.send(response);
640 }),
641 );
642 });
643
644 let send = outbound_tx
645 .try_send(message)
646 .context("failed to write to language server's stdin");
647
648 async move {
649 handle_response?;
650 send?;
651 rx.await?
652 }
653 }
654
655 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
656 Self::notify_internal::<T>(&self.outbound_tx, params)
657 }
658
659 fn notify_internal<T: notification::Notification>(
660 outbound_tx: &channel::Sender<Vec<u8>>,
661 params: T::Params,
662 ) -> Result<()> {
663 let message = serde_json::to_vec(&Notification {
664 jsonrpc: JSON_RPC_VERSION,
665 method: T::METHOD,
666 params,
667 })
668 .unwrap();
669 outbound_tx.try_send(message)?;
670 Ok(())
671 }
672}
673
674impl Drop for LanguageServer {
675 fn drop(&mut self) {
676 if let Some(shutdown) = self.shutdown() {
677 self.executor.spawn(shutdown).detach();
678 }
679 }
680}
681
682impl Subscription {
683 pub fn detach(mut self) {
684 self.method = "";
685 }
686}
687
688impl Drop for Subscription {
689 fn drop(&mut self) {
690 self.notification_handlers.lock().remove(self.method);
691 }
692}
693
694#[cfg(any(test, feature = "test-support"))]
695#[derive(Clone)]
696pub struct FakeLanguageServer {
697 pub server: Arc<LanguageServer>,
698 notifications_rx: channel::Receiver<(String, String)>,
699}
700
701#[cfg(any(test, feature = "test-support"))]
702impl LanguageServer {
703 pub fn full_capabilities() -> ServerCapabilities {
704 ServerCapabilities {
705 document_highlight_provider: Some(OneOf::Left(true)),
706 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
707 document_formatting_provider: Some(OneOf::Left(true)),
708 document_range_formatting_provider: Some(OneOf::Left(true)),
709 ..Default::default()
710 }
711 }
712
713 pub fn fake(
714 name: String,
715 capabilities: ServerCapabilities,
716 cx: AsyncAppContext,
717 ) -> (Self, FakeLanguageServer) {
718 let (stdin_writer, stdin_reader) = async_pipe::pipe();
719 let (stdout_writer, stdout_reader) = async_pipe::pipe();
720 let (notifications_tx, notifications_rx) = channel::unbounded();
721
722 let server = Self::new_internal(
723 0,
724 stdin_writer,
725 stdout_reader,
726 None,
727 Path::new("/"),
728 None,
729 cx.clone(),
730 |_| {},
731 );
732 let fake = FakeLanguageServer {
733 server: Arc::new(Self::new_internal(
734 0,
735 stdout_writer,
736 stdin_reader,
737 None,
738 Path::new("/"),
739 None,
740 cx,
741 move |msg| {
742 notifications_tx
743 .try_send((msg.method.to_string(), msg.params.get().to_string()))
744 .ok();
745 },
746 )),
747 notifications_rx,
748 };
749 fake.handle_request::<request::Initialize, _, _>({
750 let capabilities = capabilities;
751 move |_, _| {
752 let capabilities = capabilities.clone();
753 let name = name.clone();
754 async move {
755 Ok(InitializeResult {
756 capabilities,
757 server_info: Some(ServerInfo {
758 name,
759 ..Default::default()
760 }),
761 })
762 }
763 }
764 });
765
766 (server, fake)
767 }
768}
769
770#[cfg(any(test, feature = "test-support"))]
771impl FakeLanguageServer {
772 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
773 self.server.notify::<T>(params).ok();
774 }
775
776 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
777 where
778 T: request::Request,
779 T::Result: 'static + Send,
780 {
781 self.server.request::<T>(params).await
782 }
783
784 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
785 self.try_receive_notification::<T>().await.unwrap()
786 }
787
788 pub async fn try_receive_notification<T: notification::Notification>(
789 &mut self,
790 ) -> Option<T::Params> {
791 use futures::StreamExt as _;
792
793 loop {
794 let (method, params) = self.notifications_rx.next().await?;
795 if method == T::METHOD {
796 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
797 } else {
798 log::info!("skipping message in fake language server {:?}", params);
799 }
800 }
801 }
802
803 pub fn handle_request<T, F, Fut>(
804 &self,
805 mut handler: F,
806 ) -> futures::channel::mpsc::UnboundedReceiver<()>
807 where
808 T: 'static + request::Request,
809 T::Params: 'static + Send,
810 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
811 Fut: 'static + Send + Future<Output = Result<T::Result>>,
812 {
813 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
814 self.server.remove_request_handler::<T>();
815 self.server
816 .on_request::<T, _, _>(move |params, cx| {
817 let result = handler(params, cx.clone());
818 let responded_tx = responded_tx.clone();
819 async move {
820 cx.background().simulate_random_delay().await;
821 let result = result.await;
822 responded_tx.unbounded_send(()).ok();
823 result
824 }
825 })
826 .detach();
827 responded_rx
828 }
829
830 pub fn handle_notification<T, F>(
831 &self,
832 mut handler: F,
833 ) -> futures::channel::mpsc::UnboundedReceiver<()>
834 where
835 T: 'static + notification::Notification,
836 T::Params: 'static + Send,
837 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
838 {
839 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
840 self.server.remove_notification_handler::<T>();
841 self.server
842 .on_notification::<T, _>(move |params, cx| {
843 handler(params, cx.clone());
844 handled_tx.unbounded_send(()).ok();
845 })
846 .detach();
847 handled_rx
848 }
849
850 pub fn remove_request_handler<T>(&mut self)
851 where
852 T: 'static + request::Request,
853 {
854 self.server.remove_request_handler::<T>();
855 }
856
857 pub async fn start_progress(&self, token: impl Into<String>) {
858 let token = token.into();
859 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
860 token: NumberOrString::String(token.clone()),
861 })
862 .await
863 .unwrap();
864 self.notify::<notification::Progress>(ProgressParams {
865 token: NumberOrString::String(token),
866 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
867 });
868 }
869
870 pub fn end_progress(&self, token: impl Into<String>) {
871 self.notify::<notification::Progress>(ProgressParams {
872 token: NumberOrString::String(token.into()),
873 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
874 });
875 }
876}
877
878#[cfg(test)]
879mod tests {
880 use super::*;
881 use gpui::TestAppContext;
882
883 #[ctor::ctor]
884 fn init_logger() {
885 if std::env::var("RUST_LOG").is_ok() {
886 env_logger::init();
887 }
888 }
889
890 #[gpui::test]
891 async fn test_fake(cx: &mut TestAppContext) {
892 let (server, mut fake) =
893 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
894
895 let (message_tx, message_rx) = channel::unbounded();
896 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
897 server
898 .on_notification::<notification::ShowMessage, _>(move |params, _| {
899 message_tx.try_send(params).unwrap()
900 })
901 .detach();
902 server
903 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
904 diagnostics_tx.try_send(params).unwrap()
905 })
906 .detach();
907
908 let server = server.initialize(None).await.unwrap();
909 server
910 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
911 text_document: TextDocumentItem::new(
912 Url::from_str("file://a/b").unwrap(),
913 "rust".to_string(),
914 0,
915 "".to_string(),
916 ),
917 })
918 .unwrap();
919 assert_eq!(
920 fake.receive_notification::<notification::DidOpenTextDocument>()
921 .await
922 .text_document
923 .uri
924 .as_str(),
925 "file://a/b"
926 );
927
928 fake.notify::<notification::ShowMessage>(ShowMessageParams {
929 typ: MessageType::ERROR,
930 message: "ok".to_string(),
931 });
932 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
933 uri: Url::from_str("file://b/c").unwrap(),
934 version: Some(5),
935 diagnostics: vec![],
936 });
937 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
938 assert_eq!(
939 diagnostics_rx.recv().await.unwrap().uri.as_str(),
940 "file://b/c"
941 );
942
943 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
944
945 drop(server);
946 fake.receive_notification::<notification::Exit>().await;
947 }
948}