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 ffi::OsString,
20 fmt,
21 future::Future,
22 io::Write,
23 path::PathBuf,
24 str::{self, FromStr as _},
25 sync::{
26 atomic::{AtomicUsize, Ordering::SeqCst},
27 Arc, Weak,
28 },
29};
30use std::{path::Path, process::Stdio};
31use util::{ResultExt, TryFutureExt};
32
33const JSON_RPC_VERSION: &str = "2.0";
34const CONTENT_LEN_HEADER: &str = "Content-Length: ";
35
36type NotificationHandler = Box<dyn Send + FnMut(Option<usize>, &str, AsyncAppContext)>;
37type ResponseHandler = Box<dyn Send + FnOnce(Result<String, Error>)>;
38type IoHandler = Box<dyn Send + FnMut(bool, &str)>;
39
40#[derive(Debug, Clone, Deserialize)]
41pub struct LanguageServerBinary {
42 pub path: PathBuf,
43 pub arguments: Vec<OsString>,
44}
45
46pub struct LanguageServer {
47 server_id: LanguageServerId,
48 next_id: AtomicUsize,
49 outbound_tx: channel::Sender<String>,
50 name: String,
51 capabilities: ServerCapabilities,
52 code_action_kinds: Option<Vec<CodeActionKind>>,
53 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
54 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
55 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
56 executor: Arc<executor::Background>,
57 #[allow(clippy::type_complexity)]
58 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
59 output_done_rx: Mutex<Option<barrier::Receiver>>,
60 root_path: PathBuf,
61 _server: Option<Mutex<Child>>,
62}
63
64#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
65#[repr(transparent)]
66pub struct LanguageServerId(pub usize);
67
68pub enum Subscription {
69 Notification {
70 method: &'static str,
71 notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
72 },
73 Io {
74 id: usize,
75 io_handlers: Option<Weak<Mutex<HashMap<usize, IoHandler>>>>,
76 },
77}
78
79#[derive(Serialize, Deserialize)]
80struct Request<'a, T> {
81 jsonrpc: &'static str,
82 id: usize,
83 method: &'a str,
84 params: T,
85}
86
87#[derive(Serialize, Deserialize)]
88struct AnyResponse<'a> {
89 jsonrpc: &'a str,
90 id: usize,
91 #[serde(default)]
92 error: Option<Error>,
93 #[serde(borrow)]
94 result: Option<&'a RawValue>,
95}
96
97#[derive(Serialize)]
98struct Response<T> {
99 jsonrpc: &'static str,
100 id: usize,
101 result: Option<T>,
102 error: Option<Error>,
103}
104
105#[derive(Serialize, Deserialize)]
106struct Notification<'a, T> {
107 jsonrpc: &'static str,
108 #[serde(borrow)]
109 method: &'a str,
110 params: T,
111}
112
113#[derive(Debug, Clone, Deserialize)]
114struct AnyNotification<'a> {
115 #[serde(default)]
116 id: Option<usize>,
117 #[serde(borrow)]
118 method: &'a str,
119 #[serde(borrow, default)]
120 params: Option<&'a RawValue>,
121}
122
123#[derive(Debug, Serialize, Deserialize)]
124struct Error {
125 message: String,
126}
127
128impl LanguageServer {
129 pub fn new(
130 server_id: LanguageServerId,
131 binary: LanguageServerBinary,
132 root_path: &Path,
133 code_action_kinds: Option<Vec<CodeActionKind>>,
134 cx: AsyncAppContext,
135 ) -> Result<Self> {
136 let working_dir = if root_path.is_dir() {
137 root_path
138 } else {
139 root_path.parent().unwrap_or_else(|| Path::new("/"))
140 };
141
142 let mut server = process::Command::new(&binary.path)
143 .current_dir(working_dir)
144 .args(binary.arguments)
145 .stdin(Stdio::piped())
146 .stdout(Stdio::piped())
147 .stderr(Stdio::inherit())
148 .kill_on_drop(true)
149 .spawn()?;
150
151 let stdin = server.stdin.take().unwrap();
152 let stout = server.stdout.take().unwrap();
153 let mut server = Self::new_internal(
154 server_id.clone(),
155 stdin,
156 stout,
157 Some(server),
158 root_path,
159 code_action_kinds,
160 cx,
161 move |notification| {
162 log::info!(
163 "{} unhandled notification {}:\n{}",
164 server_id,
165 notification.method,
166 serde_json::to_string_pretty(
167 ¬ification
168 .params
169 .and_then(|params| Value::from_str(params.get()).ok())
170 .unwrap_or(Value::Null)
171 )
172 .unwrap(),
173 );
174 },
175 );
176
177 if let Some(name) = binary.path.file_name() {
178 server.name = name.to_string_lossy().to_string();
179 }
180
181 Ok(server)
182 }
183
184 fn new_internal<Stdin, Stdout, F>(
185 server_id: LanguageServerId,
186 stdin: Stdin,
187 stdout: Stdout,
188 server: Option<Child>,
189 root_path: &Path,
190 code_action_kinds: Option<Vec<CodeActionKind>>,
191 cx: AsyncAppContext,
192 on_unhandled_notification: F,
193 ) -> Self
194 where
195 Stdin: AsyncWrite + Unpin + Send + 'static,
196 Stdout: AsyncRead + Unpin + Send + 'static,
197 F: FnMut(AnyNotification) + 'static + Send,
198 {
199 let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
200 let (output_done_tx, output_done_rx) = barrier::channel();
201 let notification_handlers =
202 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
203 let response_handlers =
204 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
205 let io_handlers = Arc::new(Mutex::new(HashMap::default()));
206 let input_task = cx.spawn(|cx| {
207 Self::handle_input(
208 stdout,
209 on_unhandled_notification,
210 notification_handlers.clone(),
211 response_handlers.clone(),
212 io_handlers.clone(),
213 cx,
214 )
215 .log_err()
216 });
217 let output_task = cx.background().spawn({
218 Self::handle_output(
219 stdin,
220 outbound_rx,
221 output_done_tx,
222 response_handlers.clone(),
223 io_handlers.clone(),
224 )
225 .log_err()
226 });
227
228 Self {
229 server_id,
230 notification_handlers,
231 response_handlers,
232 io_handlers,
233 name: Default::default(),
234 capabilities: Default::default(),
235 code_action_kinds,
236 next_id: Default::default(),
237 outbound_tx,
238 executor: cx.background(),
239 io_tasks: Mutex::new(Some((input_task, output_task))),
240 output_done_rx: Mutex::new(Some(output_done_rx)),
241 root_path: root_path.to_path_buf(),
242 _server: server.map(|server| Mutex::new(server)),
243 }
244 }
245
246 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
247 self.code_action_kinds.clone()
248 }
249
250 async fn handle_input<Stdout, F>(
251 stdout: Stdout,
252 mut on_unhandled_notification: F,
253 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
254 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
255 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
256 cx: AsyncAppContext,
257 ) -> anyhow::Result<()>
258 where
259 Stdout: AsyncRead + Unpin + Send + 'static,
260 F: FnMut(AnyNotification) + 'static + Send,
261 {
262 let mut stdout = BufReader::new(stdout);
263 let _clear_response_handlers = util::defer({
264 let response_handlers = response_handlers.clone();
265 move || {
266 response_handlers.lock().take();
267 }
268 });
269 let mut buffer = Vec::new();
270 loop {
271 buffer.clear();
272 stdout.read_until(b'\n', &mut buffer).await?;
273 stdout.read_until(b'\n', &mut buffer).await?;
274 let header = std::str::from_utf8(&buffer)?;
275 let message_len: usize = header
276 .strip_prefix(CONTENT_LEN_HEADER)
277 .ok_or_else(|| anyhow!("invalid LSP message header {header:?}"))?
278 .trim_end()
279 .parse()?;
280
281 buffer.resize(message_len, 0);
282 stdout.read_exact(&mut buffer).await?;
283
284 if let Ok(message) = str::from_utf8(&buffer) {
285 log::trace!("incoming message:{}", message);
286 for handler in io_handlers.lock().values_mut() {
287 handler(true, message);
288 }
289 }
290
291 if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
292 if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
293 handler(
294 msg.id,
295 &msg.params.map(|params| params.get()).unwrap_or("null"),
296 cx.clone(),
297 );
298 } else {
299 on_unhandled_notification(msg);
300 }
301 } else if let Ok(AnyResponse {
302 id, error, result, ..
303 }) = serde_json::from_slice(&buffer)
304 {
305 if let Some(handler) = response_handlers
306 .lock()
307 .as_mut()
308 .and_then(|handlers| handlers.remove(&id))
309 {
310 if let Some(error) = error {
311 handler(Err(error));
312 } else if let Some(result) = result {
313 handler(Ok(result.get().into()));
314 } else {
315 handler(Ok("null".into()));
316 }
317 }
318 } else {
319 warn!(
320 "failed to deserialize LSP message:\n{}",
321 std::str::from_utf8(&buffer)?
322 );
323 }
324
325 // Don't starve the main thread when receiving lots of messages at once.
326 smol::future::yield_now().await;
327 }
328 }
329
330 async fn handle_output<Stdin>(
331 stdin: Stdin,
332 outbound_rx: channel::Receiver<String>,
333 output_done_tx: barrier::Sender,
334 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
335 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
336 ) -> anyhow::Result<()>
337 where
338 Stdin: AsyncWrite + Unpin + Send + 'static,
339 {
340 let mut stdin = BufWriter::new(stdin);
341 let _clear_response_handlers = util::defer({
342 let response_handlers = response_handlers.clone();
343 move || {
344 response_handlers.lock().take();
345 }
346 });
347 let mut content_len_buffer = Vec::new();
348 while let Ok(message) = outbound_rx.recv().await {
349 log::trace!("outgoing message:{}", message);
350 for handler in io_handlers.lock().values_mut() {
351 handler(false, &message);
352 }
353
354 content_len_buffer.clear();
355 write!(content_len_buffer, "{}", message.len()).unwrap();
356 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
357 stdin.write_all(&content_len_buffer).await?;
358 stdin.write_all("\r\n\r\n".as_bytes()).await?;
359 stdin.write_all(message.as_bytes()).await?;
360 stdin.flush().await?;
361 }
362 drop(output_done_tx);
363 Ok(())
364 }
365
366 /// Initializes a language server.
367 /// Note that `options` is used directly to construct [`InitializeParams`],
368 /// which is why it is owned.
369 pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
370 let root_uri = Url::from_file_path(&self.root_path).unwrap();
371 #[allow(deprecated)]
372 let params = InitializeParams {
373 process_id: Default::default(),
374 root_path: Default::default(),
375 root_uri: Some(root_uri.clone()),
376 initialization_options: options,
377 capabilities: ClientCapabilities {
378 workspace: Some(WorkspaceClientCapabilities {
379 configuration: Some(true),
380 did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
381 dynamic_registration: Some(true),
382 relative_pattern_support: Some(true),
383 }),
384 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
385 dynamic_registration: Some(true),
386 }),
387 workspace_folders: Some(true),
388 symbol: Some(WorkspaceSymbolClientCapabilities {
389 resolve_support: None,
390 ..WorkspaceSymbolClientCapabilities::default()
391 }),
392 inlay_hint: Some(InlayHintWorkspaceClientCapabilities {
393 refresh_support: Some(true),
394 }),
395 ..Default::default()
396 }),
397 text_document: Some(TextDocumentClientCapabilities {
398 definition: Some(GotoCapability {
399 link_support: Some(true),
400 ..Default::default()
401 }),
402 code_action: Some(CodeActionClientCapabilities {
403 code_action_literal_support: Some(CodeActionLiteralSupport {
404 code_action_kind: CodeActionKindLiteralSupport {
405 value_set: vec![
406 CodeActionKind::REFACTOR.as_str().into(),
407 CodeActionKind::QUICKFIX.as_str().into(),
408 CodeActionKind::SOURCE.as_str().into(),
409 ],
410 },
411 }),
412 data_support: Some(true),
413 resolve_support: Some(CodeActionCapabilityResolveSupport {
414 properties: vec!["edit".to_string(), "command".to_string()],
415 }),
416 ..Default::default()
417 }),
418 completion: Some(CompletionClientCapabilities {
419 completion_item: Some(CompletionItemCapability {
420 snippet_support: Some(true),
421 resolve_support: Some(CompletionItemCapabilityResolveSupport {
422 properties: vec!["additionalTextEdits".to_string()],
423 }),
424 ..Default::default()
425 }),
426 ..Default::default()
427 }),
428 rename: Some(RenameClientCapabilities {
429 prepare_support: Some(true),
430 ..Default::default()
431 }),
432 hover: Some(HoverClientCapabilities {
433 content_format: Some(vec![MarkupKind::Markdown]),
434 ..Default::default()
435 }),
436 inlay_hint: Some(InlayHintClientCapabilities {
437 resolve_support: None,
438 dynamic_registration: Some(false),
439 }),
440 ..Default::default()
441 }),
442 experimental: Some(json!({
443 "serverStatusNotification": true,
444 })),
445 window: Some(WindowClientCapabilities {
446 work_done_progress: Some(true),
447 ..Default::default()
448 }),
449 ..Default::default()
450 },
451 trace: Default::default(),
452 workspace_folders: Some(vec![WorkspaceFolder {
453 uri: root_uri,
454 name: Default::default(),
455 }]),
456 client_info: Default::default(),
457 locale: Default::default(),
458 };
459
460 let response = self.request::<request::Initialize>(params).await?;
461 if let Some(info) = response.server_info {
462 self.name = info.name;
463 }
464 self.capabilities = response.capabilities;
465
466 self.notify::<notification::Initialized>(InitializedParams {})?;
467 Ok(Arc::new(self))
468 }
469
470 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
471 if let Some(tasks) = self.io_tasks.lock().take() {
472 let response_handlers = self.response_handlers.clone();
473 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
474 let outbound_tx = self.outbound_tx.clone();
475 let executor = self.executor.clone();
476 let mut output_done = self.output_done_rx.lock().take().unwrap();
477 let shutdown_request = Self::request_internal::<request::Shutdown>(
478 &next_id,
479 &response_handlers,
480 &outbound_tx,
481 &executor,
482 (),
483 );
484 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
485 outbound_tx.close();
486 Some(
487 async move {
488 log::debug!("language server shutdown started");
489 shutdown_request.await?;
490 response_handlers.lock().take();
491 exit?;
492 output_done.recv().await;
493 log::debug!("language server shutdown finished");
494 drop(tasks);
495 anyhow::Ok(())
496 }
497 .log_err(),
498 )
499 } else {
500 None
501 }
502 }
503
504 #[must_use]
505 pub fn on_notification<T, F>(&self, f: F) -> Subscription
506 where
507 T: notification::Notification,
508 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
509 {
510 self.on_custom_notification(T::METHOD, f)
511 }
512
513 #[must_use]
514 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
515 where
516 T: request::Request,
517 T::Params: 'static + Send,
518 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
519 Fut: 'static + Future<Output = Result<T::Result>>,
520 {
521 self.on_custom_request(T::METHOD, f)
522 }
523
524 #[must_use]
525 pub fn on_io<F>(&self, f: F) -> Subscription
526 where
527 F: 'static + Send + FnMut(bool, &str),
528 {
529 let id = self.next_id.fetch_add(1, SeqCst);
530 self.io_handlers.lock().insert(id, Box::new(f));
531 Subscription::Io {
532 id,
533 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
534 }
535 }
536
537 pub fn remove_request_handler<T: request::Request>(&self) {
538 self.notification_handlers.lock().remove(T::METHOD);
539 }
540
541 pub fn remove_notification_handler<T: notification::Notification>(&self) {
542 self.notification_handlers.lock().remove(T::METHOD);
543 }
544
545 #[must_use]
546 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
547 where
548 F: 'static + Send + FnMut(Params, AsyncAppContext),
549 Params: DeserializeOwned,
550 {
551 let prev_handler = self.notification_handlers.lock().insert(
552 method,
553 Box::new(move |_, params, cx| {
554 if let Some(params) = serde_json::from_str(params).log_err() {
555 f(params, cx);
556 }
557 }),
558 );
559 assert!(
560 prev_handler.is_none(),
561 "registered multiple handlers for the same LSP method"
562 );
563 Subscription::Notification {
564 method,
565 notification_handlers: Some(self.notification_handlers.clone()),
566 }
567 }
568
569 #[must_use]
570 pub fn on_custom_request<Params, Res, Fut, F>(
571 &self,
572 method: &'static str,
573 mut f: F,
574 ) -> Subscription
575 where
576 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
577 Fut: 'static + Future<Output = Result<Res>>,
578 Params: DeserializeOwned + Send + 'static,
579 Res: Serialize,
580 {
581 let outbound_tx = self.outbound_tx.clone();
582 let prev_handler = self.notification_handlers.lock().insert(
583 method,
584 Box::new(move |id, params, cx| {
585 if let Some(id) = id {
586 match serde_json::from_str(params) {
587 Ok(params) => {
588 let response = f(params, cx.clone());
589 cx.foreground()
590 .spawn({
591 let outbound_tx = outbound_tx.clone();
592 async move {
593 let response = match response.await {
594 Ok(result) => Response {
595 jsonrpc: JSON_RPC_VERSION,
596 id,
597 result: Some(result),
598 error: None,
599 },
600 Err(error) => Response {
601 jsonrpc: JSON_RPC_VERSION,
602 id,
603 result: None,
604 error: Some(Error {
605 message: error.to_string(),
606 }),
607 },
608 };
609 if let Some(response) =
610 serde_json::to_string(&response).log_err()
611 {
612 outbound_tx.try_send(response).ok();
613 }
614 }
615 })
616 .detach();
617 }
618
619 Err(error) => {
620 log::error!(
621 "error deserializing {} request: {:?}, message: {:?}",
622 method,
623 error,
624 params
625 );
626 let response = AnyResponse {
627 jsonrpc: JSON_RPC_VERSION,
628 id,
629 result: None,
630 error: Some(Error {
631 message: error.to_string(),
632 }),
633 };
634 if let Some(response) = serde_json::to_string(&response).log_err() {
635 outbound_tx.try_send(response).ok();
636 }
637 }
638 }
639 }
640 }),
641 );
642 assert!(
643 prev_handler.is_none(),
644 "registered multiple handlers for the same LSP method"
645 );
646 Subscription::Notification {
647 method,
648 notification_handlers: Some(self.notification_handlers.clone()),
649 }
650 }
651
652 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
653 &self.name
654 }
655
656 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
657 &self.capabilities
658 }
659
660 pub fn server_id(&self) -> LanguageServerId {
661 self.server_id
662 }
663
664 pub fn root_path(&self) -> &PathBuf {
665 &self.root_path
666 }
667
668 pub fn request<T: request::Request>(
669 &self,
670 params: T::Params,
671 ) -> impl Future<Output = Result<T::Result>>
672 where
673 T::Result: 'static + Send,
674 {
675 Self::request_internal::<T>(
676 &self.next_id,
677 &self.response_handlers,
678 &self.outbound_tx,
679 &self.executor,
680 params,
681 )
682 }
683
684 fn request_internal<T: request::Request>(
685 next_id: &AtomicUsize,
686 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
687 outbound_tx: &channel::Sender<String>,
688 executor: &Arc<executor::Background>,
689 params: T::Params,
690 ) -> impl 'static + Future<Output = Result<T::Result>>
691 where
692 T::Result: 'static + Send,
693 {
694 let id = next_id.fetch_add(1, SeqCst);
695 let message = serde_json::to_string(&Request {
696 jsonrpc: JSON_RPC_VERSION,
697 id,
698 method: T::METHOD,
699 params,
700 })
701 .unwrap();
702
703 let (tx, rx) = oneshot::channel();
704 let handle_response = response_handlers
705 .lock()
706 .as_mut()
707 .ok_or_else(|| anyhow!("server shut down"))
708 .map(|handlers| {
709 let executor = executor.clone();
710 handlers.insert(
711 id,
712 Box::new(move |result| {
713 executor
714 .spawn(async move {
715 let response = match result {
716 Ok(response) => serde_json::from_str(&response)
717 .context("failed to deserialize response"),
718 Err(error) => Err(anyhow!("{}", error.message)),
719 };
720 _ = tx.send(response);
721 })
722 .detach();
723 }),
724 );
725 });
726
727 let send = outbound_tx
728 .try_send(message)
729 .context("failed to write to language server's stdin");
730
731 async move {
732 handle_response?;
733 send?;
734 rx.await?
735 }
736 }
737
738 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
739 Self::notify_internal::<T>(&self.outbound_tx, params)
740 }
741
742 fn notify_internal<T: notification::Notification>(
743 outbound_tx: &channel::Sender<String>,
744 params: T::Params,
745 ) -> Result<()> {
746 let message = serde_json::to_string(&Notification {
747 jsonrpc: JSON_RPC_VERSION,
748 method: T::METHOD,
749 params,
750 })
751 .unwrap();
752 outbound_tx.try_send(message)?;
753 Ok(())
754 }
755}
756
757impl Drop for LanguageServer {
758 fn drop(&mut self) {
759 if let Some(shutdown) = self.shutdown() {
760 self.executor.spawn(shutdown).detach();
761 }
762 }
763}
764
765impl Subscription {
766 pub fn detach(&mut self) {
767 match self {
768 Subscription::Notification {
769 notification_handlers,
770 ..
771 } => *notification_handlers = None,
772 Subscription::Io { io_handlers, .. } => *io_handlers = None,
773 }
774 }
775}
776
777impl fmt::Display for LanguageServerId {
778 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
779 self.0.fmt(f)
780 }
781}
782
783impl fmt::Debug for LanguageServer {
784 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
785 f.debug_struct("LanguageServer")
786 .field("id", &self.server_id.0)
787 .field("name", &self.name)
788 .finish_non_exhaustive()
789 }
790}
791
792impl Drop for Subscription {
793 fn drop(&mut self) {
794 match self {
795 Subscription::Notification {
796 method,
797 notification_handlers,
798 } => {
799 if let Some(handlers) = notification_handlers {
800 handlers.lock().remove(method);
801 }
802 }
803 Subscription::Io { id, io_handlers } => {
804 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
805 io_handlers.lock().remove(id);
806 }
807 }
808 }
809 }
810}
811
812#[cfg(any(test, feature = "test-support"))]
813#[derive(Clone)]
814pub struct FakeLanguageServer {
815 pub server: Arc<LanguageServer>,
816 notifications_rx: channel::Receiver<(String, String)>,
817}
818
819#[cfg(any(test, feature = "test-support"))]
820impl LanguageServer {
821 pub fn full_capabilities() -> ServerCapabilities {
822 ServerCapabilities {
823 document_highlight_provider: Some(OneOf::Left(true)),
824 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
825 document_formatting_provider: Some(OneOf::Left(true)),
826 document_range_formatting_provider: Some(OneOf::Left(true)),
827 definition_provider: Some(OneOf::Left(true)),
828 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
829 ..Default::default()
830 }
831 }
832
833 pub fn fake(
834 name: String,
835 capabilities: ServerCapabilities,
836 cx: AsyncAppContext,
837 ) -> (Self, FakeLanguageServer) {
838 let (stdin_writer, stdin_reader) = async_pipe::pipe();
839 let (stdout_writer, stdout_reader) = async_pipe::pipe();
840 let (notifications_tx, notifications_rx) = channel::unbounded();
841
842 let server = Self::new_internal(
843 LanguageServerId(0),
844 stdin_writer,
845 stdout_reader,
846 None,
847 Path::new("/"),
848 None,
849 cx.clone(),
850 |_| {},
851 );
852 let fake = FakeLanguageServer {
853 server: Arc::new(Self::new_internal(
854 LanguageServerId(0),
855 stdout_writer,
856 stdin_reader,
857 None,
858 Path::new("/"),
859 None,
860 cx,
861 move |msg| {
862 notifications_tx
863 .try_send((
864 msg.method.to_string(),
865 msg.params
866 .map(|raw_value| raw_value.get())
867 .unwrap_or("null")
868 .to_string(),
869 ))
870 .ok();
871 },
872 )),
873 notifications_rx,
874 };
875 fake.handle_request::<request::Initialize, _, _>({
876 let capabilities = capabilities;
877 move |_, _| {
878 let capabilities = capabilities.clone();
879 let name = name.clone();
880 async move {
881 Ok(InitializeResult {
882 capabilities,
883 server_info: Some(ServerInfo {
884 name,
885 ..Default::default()
886 }),
887 })
888 }
889 }
890 });
891
892 (server, fake)
893 }
894}
895
896#[cfg(any(test, feature = "test-support"))]
897impl FakeLanguageServer {
898 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
899 self.server.notify::<T>(params).ok();
900 }
901
902 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
903 where
904 T: request::Request,
905 T::Result: 'static + Send,
906 {
907 self.server.executor.start_waiting();
908 self.server.request::<T>(params).await
909 }
910
911 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
912 self.server.executor.start_waiting();
913 self.try_receive_notification::<T>().await.unwrap()
914 }
915
916 pub async fn try_receive_notification<T: notification::Notification>(
917 &mut self,
918 ) -> Option<T::Params> {
919 use futures::StreamExt as _;
920
921 loop {
922 let (method, params) = self.notifications_rx.next().await?;
923 if method == T::METHOD {
924 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
925 } else {
926 log::info!("skipping message in fake language server {:?}", params);
927 }
928 }
929 }
930
931 pub fn handle_request<T, F, Fut>(
932 &self,
933 mut handler: F,
934 ) -> futures::channel::mpsc::UnboundedReceiver<()>
935 where
936 T: 'static + request::Request,
937 T::Params: 'static + Send,
938 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
939 Fut: 'static + Send + Future<Output = Result<T::Result>>,
940 {
941 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
942 self.server.remove_request_handler::<T>();
943 self.server
944 .on_request::<T, _, _>(move |params, cx| {
945 let result = handler(params, cx.clone());
946 let responded_tx = responded_tx.clone();
947 async move {
948 cx.background().simulate_random_delay().await;
949 let result = result.await;
950 responded_tx.unbounded_send(()).ok();
951 result
952 }
953 })
954 .detach();
955 responded_rx
956 }
957
958 pub fn handle_notification<T, F>(
959 &self,
960 mut handler: F,
961 ) -> futures::channel::mpsc::UnboundedReceiver<()>
962 where
963 T: 'static + notification::Notification,
964 T::Params: 'static + Send,
965 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
966 {
967 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
968 self.server.remove_notification_handler::<T>();
969 self.server
970 .on_notification::<T, _>(move |params, cx| {
971 handler(params, cx.clone());
972 handled_tx.unbounded_send(()).ok();
973 })
974 .detach();
975 handled_rx
976 }
977
978 pub fn remove_request_handler<T>(&mut self)
979 where
980 T: 'static + request::Request,
981 {
982 self.server.remove_request_handler::<T>();
983 }
984
985 pub async fn start_progress(&self, token: impl Into<String>) {
986 let token = token.into();
987 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
988 token: NumberOrString::String(token.clone()),
989 })
990 .await
991 .unwrap();
992 self.notify::<notification::Progress>(ProgressParams {
993 token: NumberOrString::String(token),
994 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
995 });
996 }
997
998 pub fn end_progress(&self, token: impl Into<String>) {
999 self.notify::<notification::Progress>(ProgressParams {
1000 token: NumberOrString::String(token.into()),
1001 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1002 });
1003 }
1004}
1005
1006#[cfg(test)]
1007mod tests {
1008 use super::*;
1009 use gpui::TestAppContext;
1010
1011 #[ctor::ctor]
1012 fn init_logger() {
1013 if std::env::var("RUST_LOG").is_ok() {
1014 env_logger::init();
1015 }
1016 }
1017
1018 #[gpui::test]
1019 async fn test_fake(cx: &mut TestAppContext) {
1020 let (server, mut fake) =
1021 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
1022
1023 let (message_tx, message_rx) = channel::unbounded();
1024 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1025 server
1026 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1027 message_tx.try_send(params).unwrap()
1028 })
1029 .detach();
1030 server
1031 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1032 diagnostics_tx.try_send(params).unwrap()
1033 })
1034 .detach();
1035
1036 let server = server.initialize(None).await.unwrap();
1037 server
1038 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1039 text_document: TextDocumentItem::new(
1040 Url::from_str("file://a/b").unwrap(),
1041 "rust".to_string(),
1042 0,
1043 "".to_string(),
1044 ),
1045 })
1046 .unwrap();
1047 assert_eq!(
1048 fake.receive_notification::<notification::DidOpenTextDocument>()
1049 .await
1050 .text_document
1051 .uri
1052 .as_str(),
1053 "file://a/b"
1054 );
1055
1056 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1057 typ: MessageType::ERROR,
1058 message: "ok".to_string(),
1059 });
1060 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1061 uri: Url::from_str("file://b/c").unwrap(),
1062 version: Some(5),
1063 diagnostics: vec![],
1064 });
1065 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1066 assert_eq!(
1067 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1068 "file://b/c"
1069 );
1070
1071 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1072
1073 drop(server);
1074 fake.receive_notification::<notification::Exit>().await;
1075 }
1076}