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 fmt,
20 future::Future,
21 io::Write,
22 path::PathBuf,
23 str::FromStr,
24 sync::{
25 atomic::{AtomicUsize, Ordering::SeqCst},
26 Arc,
27 },
28};
29use std::{path::Path, process::Stdio};
30use util::{ResultExt, TryFutureExt};
31
32const JSON_RPC_VERSION: &str = "2.0";
33const CONTENT_LEN_HEADER: &str = "Content-Length: ";
34
35type NotificationHandler = Box<dyn Send + FnMut(Option<usize>, &str, AsyncAppContext)>;
36type ResponseHandler = Box<dyn Send + FnOnce(Result<&str, Error>)>;
37
38pub struct LanguageServer {
39 server_id: LanguageServerId,
40 next_id: AtomicUsize,
41 outbound_tx: channel::Sender<Vec<u8>>,
42 name: String,
43 capabilities: ServerCapabilities,
44 code_action_kinds: Option<Vec<CodeActionKind>>,
45 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
46 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
47 executor: Arc<executor::Background>,
48 #[allow(clippy::type_complexity)]
49 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
50 output_done_rx: Mutex<Option<barrier::Receiver>>,
51 root_path: PathBuf,
52 _server: Option<Child>,
53}
54
55#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
56#[repr(transparent)]
57pub struct LanguageServerId(pub usize);
58
59pub struct Subscription {
60 method: &'static str,
61 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
62}
63
64#[derive(Serialize, Deserialize)]
65struct Request<'a, T> {
66 jsonrpc: &'static str,
67 id: usize,
68 method: &'a str,
69 params: T,
70}
71
72#[derive(Serialize, Deserialize)]
73struct AnyResponse<'a> {
74 jsonrpc: &'a str,
75 id: usize,
76 #[serde(default)]
77 error: Option<Error>,
78 #[serde(borrow)]
79 result: Option<&'a RawValue>,
80}
81
82#[derive(Serialize)]
83struct Response<T> {
84 jsonrpc: &'static str,
85 id: usize,
86 result: Option<T>,
87 error: Option<Error>,
88}
89
90#[derive(Serialize, Deserialize)]
91struct Notification<'a, T> {
92 jsonrpc: &'static str,
93 #[serde(borrow)]
94 method: &'a str,
95 params: T,
96}
97
98#[derive(Deserialize)]
99struct AnyNotification<'a> {
100 #[serde(default)]
101 id: Option<usize>,
102 #[serde(borrow)]
103 method: &'a str,
104 #[serde(borrow)]
105 params: &'a RawValue,
106}
107
108#[derive(Debug, Serialize, Deserialize)]
109struct Error {
110 message: String,
111}
112
113impl LanguageServer {
114 pub fn new<T: AsRef<std::ffi::OsStr>>(
115 server_id: LanguageServerId,
116 binary_path: &Path,
117 arguments: &[T],
118 root_path: &Path,
119 code_action_kinds: Option<Vec<CodeActionKind>>,
120 cx: AsyncAppContext,
121 ) -> Result<Self> {
122 let working_dir = if root_path.is_dir() {
123 root_path
124 } else {
125 root_path.parent().unwrap_or_else(|| Path::new("/"))
126 };
127
128 let mut server = process::Command::new(binary_path)
129 .current_dir(working_dir)
130 .args(arguments)
131 .stdin(Stdio::piped())
132 .stdout(Stdio::piped())
133 .stderr(Stdio::inherit())
134 .kill_on_drop(true)
135 .spawn()?;
136
137 let stdin = server.stdin.take().unwrap();
138 let stout = server.stdout.take().unwrap();
139 let mut server = Self::new_internal(
140 server_id,
141 stdin,
142 stout,
143 Some(server),
144 root_path,
145 code_action_kinds,
146 cx,
147 |notification| {
148 log::info!(
149 "unhandled notification {}:\n{}",
150 notification.method,
151 serde_json::to_string_pretty(
152 &Value::from_str(notification.params.get()).unwrap()
153 )
154 .unwrap()
155 );
156 },
157 );
158
159 if let Some(name) = binary_path.file_name() {
160 server.name = name.to_string_lossy().to_string();
161 }
162 Ok(server)
163 }
164
165 fn new_internal<Stdin, Stdout, F>(
166 server_id: LanguageServerId,
167 stdin: Stdin,
168 stdout: Stdout,
169 server: Option<Child>,
170 root_path: &Path,
171 code_action_kinds: Option<Vec<CodeActionKind>>,
172 cx: AsyncAppContext,
173 on_unhandled_notification: F,
174 ) -> Self
175 where
176 Stdin: AsyncWrite + Unpin + Send + 'static,
177 Stdout: AsyncRead + Unpin + Send + 'static,
178 F: FnMut(AnyNotification) + 'static + Send,
179 {
180 let (outbound_tx, outbound_rx) = channel::unbounded::<Vec<u8>>();
181 let notification_handlers =
182 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
183 let response_handlers =
184 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
185 let input_task = cx.spawn(|cx| {
186 let notification_handlers = notification_handlers.clone();
187 let response_handlers = response_handlers.clone();
188 Self::handle_input(
189 stdout,
190 on_unhandled_notification,
191 notification_handlers,
192 response_handlers,
193 cx,
194 )
195 .log_err()
196 });
197 let (output_done_tx, output_done_rx) = barrier::channel();
198 let output_task = cx.background().spawn({
199 let response_handlers = response_handlers.clone();
200 Self::handle_output(stdin, outbound_rx, output_done_tx, response_handlers).log_err()
201 });
202
203 Self {
204 server_id,
205 notification_handlers,
206 response_handlers,
207 name: Default::default(),
208 capabilities: Default::default(),
209 code_action_kinds,
210 next_id: Default::default(),
211 outbound_tx,
212 executor: cx.background(),
213 io_tasks: Mutex::new(Some((input_task, output_task))),
214 output_done_rx: Mutex::new(Some(output_done_rx)),
215 root_path: root_path.to_path_buf(),
216 _server: server,
217 }
218 }
219
220 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
221 self.code_action_kinds.clone()
222 }
223
224 async fn handle_input<Stdout, F>(
225 stdout: Stdout,
226 mut on_unhandled_notification: F,
227 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
228 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
229 cx: AsyncAppContext,
230 ) -> anyhow::Result<()>
231 where
232 Stdout: AsyncRead + Unpin + Send + 'static,
233 F: FnMut(AnyNotification) + 'static + Send,
234 {
235 let mut stdout = BufReader::new(stdout);
236 let _clear_response_handlers = util::defer({
237 let response_handlers = response_handlers.clone();
238 move || {
239 response_handlers.lock().take();
240 }
241 });
242 let mut buffer = Vec::new();
243 loop {
244 buffer.clear();
245 stdout.read_until(b'\n', &mut buffer).await?;
246 stdout.read_until(b'\n', &mut buffer).await?;
247 let message_len: usize = std::str::from_utf8(&buffer)?
248 .strip_prefix(CONTENT_LEN_HEADER)
249 .ok_or_else(|| anyhow!("invalid header"))?
250 .trim_end()
251 .parse()?;
252
253 buffer.resize(message_len, 0);
254 stdout.read_exact(&mut buffer).await?;
255 log::trace!("incoming message:{}", String::from_utf8_lossy(&buffer));
256
257 if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
258 if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
259 handler(msg.id, msg.params.get(), cx.clone());
260 } else {
261 on_unhandled_notification(msg);
262 }
263 } else if let Ok(AnyResponse {
264 id, error, result, ..
265 }) = serde_json::from_slice(&buffer)
266 {
267 if let Some(handler) = response_handlers
268 .lock()
269 .as_mut()
270 .and_then(|handlers| handlers.remove(&id))
271 {
272 if let Some(error) = error {
273 handler(Err(error));
274 } else if let Some(result) = result {
275 handler(Ok(result.get()));
276 } else {
277 handler(Ok("null"));
278 }
279 }
280 } else {
281 warn!(
282 "Failed to deserialize message:\n{}",
283 std::str::from_utf8(&buffer)?
284 );
285 }
286
287 // Don't starve the main thread when receiving lots of messages at once.
288 smol::future::yield_now().await;
289 }
290 }
291
292 async fn handle_output<Stdin>(
293 stdin: Stdin,
294 outbound_rx: channel::Receiver<Vec<u8>>,
295 output_done_tx: barrier::Sender,
296 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
297 ) -> anyhow::Result<()>
298 where
299 Stdin: AsyncWrite + Unpin + Send + 'static,
300 {
301 let mut stdin = BufWriter::new(stdin);
302 let _clear_response_handlers = util::defer({
303 let response_handlers = response_handlers.clone();
304 move || {
305 response_handlers.lock().take();
306 }
307 });
308 let mut content_len_buffer = Vec::new();
309 while let Ok(message) = outbound_rx.recv().await {
310 log::trace!("outgoing message:{}", String::from_utf8_lossy(&message));
311 content_len_buffer.clear();
312 write!(content_len_buffer, "{}", message.len()).unwrap();
313 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
314 stdin.write_all(&content_len_buffer).await?;
315 stdin.write_all("\r\n\r\n".as_bytes()).await?;
316 stdin.write_all(&message).await?;
317 stdin.flush().await?;
318 }
319 drop(output_done_tx);
320 Ok(())
321 }
322
323 /// Initializes a language server.
324 /// Note that `options` is used directly to construct [`InitializeParams`],
325 /// which is why it is owned.
326 pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
327 let root_uri = Url::from_file_path(&self.root_path).unwrap();
328 #[allow(deprecated)]
329 let params = InitializeParams {
330 process_id: Default::default(),
331 root_path: Default::default(),
332 root_uri: Some(root_uri.clone()),
333 initialization_options: options,
334 capabilities: ClientCapabilities {
335 workspace: Some(WorkspaceClientCapabilities {
336 configuration: Some(true),
337 did_change_watched_files: Some(DynamicRegistrationClientCapabilities {
338 dynamic_registration: Some(true),
339 }),
340 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
341 dynamic_registration: Some(true),
342 }),
343 workspace_folders: Some(true),
344 ..Default::default()
345 }),
346 text_document: Some(TextDocumentClientCapabilities {
347 definition: Some(GotoCapability {
348 link_support: Some(true),
349 ..Default::default()
350 }),
351 code_action: Some(CodeActionClientCapabilities {
352 code_action_literal_support: Some(CodeActionLiteralSupport {
353 code_action_kind: CodeActionKindLiteralSupport {
354 value_set: vec![
355 CodeActionKind::REFACTOR.as_str().into(),
356 CodeActionKind::QUICKFIX.as_str().into(),
357 CodeActionKind::SOURCE.as_str().into(),
358 ],
359 },
360 }),
361 data_support: Some(true),
362 resolve_support: Some(CodeActionCapabilityResolveSupport {
363 properties: vec!["edit".to_string(), "command".to_string()],
364 }),
365 ..Default::default()
366 }),
367 completion: Some(CompletionClientCapabilities {
368 completion_item: Some(CompletionItemCapability {
369 snippet_support: Some(true),
370 resolve_support: Some(CompletionItemCapabilityResolveSupport {
371 properties: vec!["additionalTextEdits".to_string()],
372 }),
373 ..Default::default()
374 }),
375 ..Default::default()
376 }),
377 rename: Some(RenameClientCapabilities {
378 prepare_support: Some(true),
379 ..Default::default()
380 }),
381 hover: Some(HoverClientCapabilities {
382 content_format: Some(vec![MarkupKind::Markdown]),
383 ..Default::default()
384 }),
385 ..Default::default()
386 }),
387 experimental: Some(json!({
388 "serverStatusNotification": true,
389 })),
390 window: Some(WindowClientCapabilities {
391 work_done_progress: Some(true),
392 ..Default::default()
393 }),
394 ..Default::default()
395 },
396 trace: Default::default(),
397 workspace_folders: Some(vec![WorkspaceFolder {
398 uri: root_uri,
399 name: Default::default(),
400 }]),
401 client_info: Default::default(),
402 locale: Default::default(),
403 };
404
405 let response = self.request::<request::Initialize>(params).await?;
406 if let Some(info) = response.server_info {
407 self.name = info.name;
408 }
409 self.capabilities = response.capabilities;
410
411 self.notify::<notification::Initialized>(InitializedParams {})?;
412 Ok(Arc::new(self))
413 }
414
415 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
416 if let Some(tasks) = self.io_tasks.lock().take() {
417 let response_handlers = self.response_handlers.clone();
418 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
419 let outbound_tx = self.outbound_tx.clone();
420 let mut output_done = self.output_done_rx.lock().take().unwrap();
421 let shutdown_request = Self::request_internal::<request::Shutdown>(
422 &next_id,
423 &response_handlers,
424 &outbound_tx,
425 (),
426 );
427 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
428 outbound_tx.close();
429 Some(
430 async move {
431 log::debug!("language server shutdown started");
432 shutdown_request.await?;
433 response_handlers.lock().take();
434 exit?;
435 output_done.recv().await;
436 log::debug!("language server shutdown finished");
437 drop(tasks);
438 anyhow::Ok(())
439 }
440 .log_err(),
441 )
442 } else {
443 None
444 }
445 }
446
447 #[must_use]
448 pub fn on_notification<T, F>(&self, f: F) -> Subscription
449 where
450 T: notification::Notification,
451 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
452 {
453 self.on_custom_notification(T::METHOD, f)
454 }
455
456 #[must_use]
457 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
458 where
459 T: request::Request,
460 T::Params: 'static + Send,
461 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
462 Fut: 'static + Future<Output = Result<T::Result>>,
463 {
464 self.on_custom_request(T::METHOD, f)
465 }
466
467 pub fn remove_request_handler<T: request::Request>(&self) {
468 self.notification_handlers.lock().remove(T::METHOD);
469 }
470
471 pub fn remove_notification_handler<T: notification::Notification>(&self) {
472 self.notification_handlers.lock().remove(T::METHOD);
473 }
474
475 #[must_use]
476 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
477 where
478 F: 'static + Send + FnMut(Params, AsyncAppContext),
479 Params: DeserializeOwned,
480 {
481 let prev_handler = self.notification_handlers.lock().insert(
482 method,
483 Box::new(move |_, params, cx| {
484 if let Some(params) = serde_json::from_str(params).log_err() {
485 f(params, cx);
486 }
487 }),
488 );
489 assert!(
490 prev_handler.is_none(),
491 "registered multiple handlers for the same LSP method"
492 );
493 Subscription {
494 method,
495 notification_handlers: self.notification_handlers.clone(),
496 }
497 }
498
499 #[must_use]
500 pub fn on_custom_request<Params, Res, Fut, F>(
501 &self,
502 method: &'static str,
503 mut f: F,
504 ) -> Subscription
505 where
506 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
507 Fut: 'static + Future<Output = Result<Res>>,
508 Params: DeserializeOwned + Send + 'static,
509 Res: Serialize,
510 {
511 let outbound_tx = self.outbound_tx.clone();
512 let prev_handler = self.notification_handlers.lock().insert(
513 method,
514 Box::new(move |id, params, cx| {
515 if let Some(id) = id {
516 match serde_json::from_str(params) {
517 Ok(params) => {
518 let response = f(params, cx.clone());
519 cx.foreground()
520 .spawn({
521 let outbound_tx = outbound_tx.clone();
522 async move {
523 let response = match response.await {
524 Ok(result) => Response {
525 jsonrpc: JSON_RPC_VERSION,
526 id,
527 result: Some(result),
528 error: None,
529 },
530 Err(error) => Response {
531 jsonrpc: JSON_RPC_VERSION,
532 id,
533 result: None,
534 error: Some(Error {
535 message: error.to_string(),
536 }),
537 },
538 };
539 if let Some(response) =
540 serde_json::to_vec(&response).log_err()
541 {
542 outbound_tx.try_send(response).ok();
543 }
544 }
545 })
546 .detach();
547 }
548 Err(error) => {
549 log::error!(
550 "error deserializing {} request: {:?}, message: {:?}",
551 method,
552 error,
553 params
554 );
555 let response = AnyResponse {
556 jsonrpc: JSON_RPC_VERSION,
557 id,
558 result: None,
559 error: Some(Error {
560 message: error.to_string(),
561 }),
562 };
563 if let Some(response) = serde_json::to_vec(&response).log_err() {
564 outbound_tx.try_send(response).ok();
565 }
566 }
567 }
568 }
569 }),
570 );
571 assert!(
572 prev_handler.is_none(),
573 "registered multiple handlers for the same LSP method"
574 );
575 Subscription {
576 method,
577 notification_handlers: self.notification_handlers.clone(),
578 }
579 }
580
581 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
582 &self.name
583 }
584
585 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
586 &self.capabilities
587 }
588
589 pub fn server_id(&self) -> LanguageServerId {
590 self.server_id
591 }
592
593 pub fn root_path(&self) -> &PathBuf {
594 &self.root_path
595 }
596
597 pub fn request<T: request::Request>(
598 &self,
599 params: T::Params,
600 ) -> impl Future<Output = Result<T::Result>>
601 where
602 T::Result: 'static + Send,
603 {
604 Self::request_internal::<T>(
605 &self.next_id,
606 &self.response_handlers,
607 &self.outbound_tx,
608 params,
609 )
610 }
611
612 fn request_internal<T: request::Request>(
613 next_id: &AtomicUsize,
614 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
615 outbound_tx: &channel::Sender<Vec<u8>>,
616 params: T::Params,
617 ) -> impl 'static + Future<Output = Result<T::Result>>
618 where
619 T::Result: 'static + Send,
620 {
621 let id = next_id.fetch_add(1, SeqCst);
622 let message = serde_json::to_vec(&Request {
623 jsonrpc: JSON_RPC_VERSION,
624 id,
625 method: T::METHOD,
626 params,
627 })
628 .unwrap();
629
630 let (tx, rx) = oneshot::channel();
631 let handle_response = response_handlers
632 .lock()
633 .as_mut()
634 .ok_or_else(|| anyhow!("server shut down"))
635 .map(|handlers| {
636 handlers.insert(
637 id,
638 Box::new(move |result| {
639 let response = match result {
640 Ok(response) => serde_json::from_str(response)
641 .context("failed to deserialize response"),
642 Err(error) => Err(anyhow!("{}", error.message)),
643 };
644 let _ = tx.send(response);
645 }),
646 );
647 });
648
649 let send = outbound_tx
650 .try_send(message)
651 .context("failed to write to language server's stdin");
652
653 async move {
654 handle_response?;
655 send?;
656 rx.await?
657 }
658 }
659
660 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
661 Self::notify_internal::<T>(&self.outbound_tx, params)
662 }
663
664 fn notify_internal<T: notification::Notification>(
665 outbound_tx: &channel::Sender<Vec<u8>>,
666 params: T::Params,
667 ) -> Result<()> {
668 let message = serde_json::to_vec(&Notification {
669 jsonrpc: JSON_RPC_VERSION,
670 method: T::METHOD,
671 params,
672 })
673 .unwrap();
674 outbound_tx.try_send(message)?;
675 Ok(())
676 }
677}
678
679impl Drop for LanguageServer {
680 fn drop(&mut self) {
681 if let Some(shutdown) = self.shutdown() {
682 self.executor.spawn(shutdown).detach();
683 }
684 }
685}
686
687impl Subscription {
688 pub fn detach(mut self) {
689 self.method = "";
690 }
691}
692
693impl fmt::Display for LanguageServerId {
694 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
695 self.0.fmt(f)
696 }
697}
698
699impl Drop for Subscription {
700 fn drop(&mut self) {
701 self.notification_handlers.lock().remove(self.method);
702 }
703}
704
705#[cfg(any(test, feature = "test-support"))]
706#[derive(Clone)]
707pub struct FakeLanguageServer {
708 pub server: Arc<LanguageServer>,
709 notifications_rx: channel::Receiver<(String, String)>,
710}
711
712#[cfg(any(test, feature = "test-support"))]
713impl LanguageServer {
714 pub fn full_capabilities() -> ServerCapabilities {
715 ServerCapabilities {
716 document_highlight_provider: Some(OneOf::Left(true)),
717 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
718 document_formatting_provider: Some(OneOf::Left(true)),
719 document_range_formatting_provider: Some(OneOf::Left(true)),
720 ..Default::default()
721 }
722 }
723
724 pub fn fake(
725 name: String,
726 capabilities: ServerCapabilities,
727 cx: AsyncAppContext,
728 ) -> (Self, FakeLanguageServer) {
729 let (stdin_writer, stdin_reader) = async_pipe::pipe();
730 let (stdout_writer, stdout_reader) = async_pipe::pipe();
731 let (notifications_tx, notifications_rx) = channel::unbounded();
732
733 let server = Self::new_internal(
734 LanguageServerId(0),
735 stdin_writer,
736 stdout_reader,
737 None,
738 Path::new("/"),
739 None,
740 cx.clone(),
741 |_| {},
742 );
743 let fake = FakeLanguageServer {
744 server: Arc::new(Self::new_internal(
745 LanguageServerId(0),
746 stdout_writer,
747 stdin_reader,
748 None,
749 Path::new("/"),
750 None,
751 cx,
752 move |msg| {
753 notifications_tx
754 .try_send((msg.method.to_string(), msg.params.get().to_string()))
755 .ok();
756 },
757 )),
758 notifications_rx,
759 };
760 fake.handle_request::<request::Initialize, _, _>({
761 let capabilities = capabilities;
762 move |_, _| {
763 let capabilities = capabilities.clone();
764 let name = name.clone();
765 async move {
766 Ok(InitializeResult {
767 capabilities,
768 server_info: Some(ServerInfo {
769 name,
770 ..Default::default()
771 }),
772 })
773 }
774 }
775 });
776
777 (server, fake)
778 }
779}
780
781#[cfg(any(test, feature = "test-support"))]
782impl FakeLanguageServer {
783 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
784 self.server.notify::<T>(params).ok();
785 }
786
787 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
788 where
789 T: request::Request,
790 T::Result: 'static + Send,
791 {
792 self.server.request::<T>(params).await
793 }
794
795 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
796 self.try_receive_notification::<T>().await.unwrap()
797 }
798
799 pub async fn try_receive_notification<T: notification::Notification>(
800 &mut self,
801 ) -> Option<T::Params> {
802 use futures::StreamExt as _;
803
804 loop {
805 let (method, params) = self.notifications_rx.next().await?;
806 if method == T::METHOD {
807 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
808 } else {
809 log::info!("skipping message in fake language server {:?}", params);
810 }
811 }
812 }
813
814 pub fn handle_request<T, F, Fut>(
815 &self,
816 mut handler: F,
817 ) -> futures::channel::mpsc::UnboundedReceiver<()>
818 where
819 T: 'static + request::Request,
820 T::Params: 'static + Send,
821 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
822 Fut: 'static + Send + Future<Output = Result<T::Result>>,
823 {
824 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
825 self.server.remove_request_handler::<T>();
826 self.server
827 .on_request::<T, _, _>(move |params, cx| {
828 let result = handler(params, cx.clone());
829 let responded_tx = responded_tx.clone();
830 async move {
831 cx.background().simulate_random_delay().await;
832 let result = result.await;
833 responded_tx.unbounded_send(()).ok();
834 result
835 }
836 })
837 .detach();
838 responded_rx
839 }
840
841 pub fn handle_notification<T, F>(
842 &self,
843 mut handler: F,
844 ) -> futures::channel::mpsc::UnboundedReceiver<()>
845 where
846 T: 'static + notification::Notification,
847 T::Params: 'static + Send,
848 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
849 {
850 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
851 self.server.remove_notification_handler::<T>();
852 self.server
853 .on_notification::<T, _>(move |params, cx| {
854 handler(params, cx.clone());
855 handled_tx.unbounded_send(()).ok();
856 })
857 .detach();
858 handled_rx
859 }
860
861 pub fn remove_request_handler<T>(&mut self)
862 where
863 T: 'static + request::Request,
864 {
865 self.server.remove_request_handler::<T>();
866 }
867
868 pub async fn start_progress(&self, token: impl Into<String>) {
869 let token = token.into();
870 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
871 token: NumberOrString::String(token.clone()),
872 })
873 .await
874 .unwrap();
875 self.notify::<notification::Progress>(ProgressParams {
876 token: NumberOrString::String(token),
877 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
878 });
879 }
880
881 pub fn end_progress(&self, token: impl Into<String>) {
882 self.notify::<notification::Progress>(ProgressParams {
883 token: NumberOrString::String(token.into()),
884 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
885 });
886 }
887}
888
889#[cfg(test)]
890mod tests {
891 use super::*;
892 use gpui::TestAppContext;
893
894 #[ctor::ctor]
895 fn init_logger() {
896 if std::env::var("RUST_LOG").is_ok() {
897 env_logger::init();
898 }
899 }
900
901 #[gpui::test]
902 async fn test_fake(cx: &mut TestAppContext) {
903 let (server, mut fake) =
904 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
905
906 let (message_tx, message_rx) = channel::unbounded();
907 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
908 server
909 .on_notification::<notification::ShowMessage, _>(move |params, _| {
910 message_tx.try_send(params).unwrap()
911 })
912 .detach();
913 server
914 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
915 diagnostics_tx.try_send(params).unwrap()
916 })
917 .detach();
918
919 let server = server.initialize(None).await.unwrap();
920 server
921 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
922 text_document: TextDocumentItem::new(
923 Url::from_str("file://a/b").unwrap(),
924 "rust".to_string(),
925 0,
926 "".to_string(),
927 ),
928 })
929 .unwrap();
930 assert_eq!(
931 fake.receive_notification::<notification::DidOpenTextDocument>()
932 .await
933 .text_document
934 .uri
935 .as_str(),
936 "file://a/b"
937 );
938
939 fake.notify::<notification::ShowMessage>(ShowMessageParams {
940 typ: MessageType::ERROR,
941 message: "ok".to_string(),
942 });
943 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
944 uri: Url::from_str("file://b/c").unwrap(),
945 version: Some(5),
946 diagnostics: vec![],
947 });
948 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
949 assert_eq!(
950 diagnostics_rx.recv().await.unwrap().uri.as_str(),
951 "file://b/c"
952 );
953
954 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
955
956 drop(server);
957 fake.receive_notification::<notification::Exit>().await;
958 }
959}