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)]
80pub struct 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: Some(InlayHintResolveClientCapabilities {
438 properties: vec![
439 "textEdits".to_string(),
440 "tooltip".to_string(),
441 "label.tooltip".to_string(),
442 "label.location".to_string(),
443 "label.command".to_string(),
444 ],
445 }),
446 dynamic_registration: Some(false),
447 }),
448 ..Default::default()
449 }),
450 experimental: Some(json!({
451 "serverStatusNotification": true,
452 })),
453 window: Some(WindowClientCapabilities {
454 work_done_progress: Some(true),
455 ..Default::default()
456 }),
457 ..Default::default()
458 },
459 trace: Default::default(),
460 workspace_folders: Some(vec![WorkspaceFolder {
461 uri: root_uri,
462 name: Default::default(),
463 }]),
464 client_info: Default::default(),
465 locale: Default::default(),
466 };
467
468 let response = self.request::<request::Initialize>(params).await?;
469 if let Some(info) = response.server_info {
470 self.name = info.name;
471 }
472 self.capabilities = response.capabilities;
473
474 self.notify::<notification::Initialized>(InitializedParams {})?;
475 Ok(Arc::new(self))
476 }
477
478 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
479 if let Some(tasks) = self.io_tasks.lock().take() {
480 let response_handlers = self.response_handlers.clone();
481 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
482 let outbound_tx = self.outbound_tx.clone();
483 let executor = self.executor.clone();
484 let mut output_done = self.output_done_rx.lock().take().unwrap();
485 let shutdown_request = Self::request_internal::<request::Shutdown>(
486 &next_id,
487 &response_handlers,
488 &outbound_tx,
489 &executor,
490 (),
491 );
492 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
493 outbound_tx.close();
494 Some(
495 async move {
496 log::debug!("language server shutdown started");
497 shutdown_request.await?;
498 response_handlers.lock().take();
499 exit?;
500 output_done.recv().await;
501 log::debug!("language server shutdown finished");
502 drop(tasks);
503 anyhow::Ok(())
504 }
505 .log_err(),
506 )
507 } else {
508 None
509 }
510 }
511
512 #[must_use]
513 pub fn on_notification<T, F>(&self, f: F) -> Subscription
514 where
515 T: notification::Notification,
516 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
517 {
518 self.on_custom_notification(T::METHOD, f)
519 }
520
521 #[must_use]
522 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
523 where
524 T: request::Request,
525 T::Params: 'static + Send,
526 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
527 Fut: 'static + Future<Output = Result<T::Result>>,
528 {
529 self.on_custom_request(T::METHOD, f)
530 }
531
532 #[must_use]
533 pub fn on_io<F>(&self, f: F) -> Subscription
534 where
535 F: 'static + Send + FnMut(bool, &str),
536 {
537 let id = self.next_id.fetch_add(1, SeqCst);
538 self.io_handlers.lock().insert(id, Box::new(f));
539 Subscription::Io {
540 id,
541 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
542 }
543 }
544
545 pub fn remove_request_handler<T: request::Request>(&self) {
546 self.notification_handlers.lock().remove(T::METHOD);
547 }
548
549 pub fn remove_notification_handler<T: notification::Notification>(&self) {
550 self.notification_handlers.lock().remove(T::METHOD);
551 }
552
553 #[must_use]
554 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
555 where
556 F: 'static + Send + FnMut(Params, AsyncAppContext),
557 Params: DeserializeOwned,
558 {
559 let prev_handler = self.notification_handlers.lock().insert(
560 method,
561 Box::new(move |_, params, cx| {
562 if let Some(params) = serde_json::from_str(params).log_err() {
563 f(params, cx);
564 }
565 }),
566 );
567 assert!(
568 prev_handler.is_none(),
569 "registered multiple handlers for the same LSP method"
570 );
571 Subscription::Notification {
572 method,
573 notification_handlers: Some(self.notification_handlers.clone()),
574 }
575 }
576
577 #[must_use]
578 pub fn on_custom_request<Params, Res, Fut, F>(
579 &self,
580 method: &'static str,
581 mut f: F,
582 ) -> Subscription
583 where
584 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
585 Fut: 'static + Future<Output = Result<Res>>,
586 Params: DeserializeOwned + Send + 'static,
587 Res: Serialize,
588 {
589 let outbound_tx = self.outbound_tx.clone();
590 let prev_handler = self.notification_handlers.lock().insert(
591 method,
592 Box::new(move |id, params, cx| {
593 if let Some(id) = id {
594 match serde_json::from_str(params) {
595 Ok(params) => {
596 let response = f(params, cx.clone());
597 cx.foreground()
598 .spawn({
599 let outbound_tx = outbound_tx.clone();
600 async move {
601 let response = match response.await {
602 Ok(result) => Response {
603 jsonrpc: JSON_RPC_VERSION,
604 id,
605 result: Some(result),
606 error: None,
607 },
608 Err(error) => Response {
609 jsonrpc: JSON_RPC_VERSION,
610 id,
611 result: None,
612 error: Some(Error {
613 message: error.to_string(),
614 }),
615 },
616 };
617 if let Some(response) =
618 serde_json::to_string(&response).log_err()
619 {
620 outbound_tx.try_send(response).ok();
621 }
622 }
623 })
624 .detach();
625 }
626
627 Err(error) => {
628 log::error!(
629 "error deserializing {} request: {:?}, message: {:?}",
630 method,
631 error,
632 params
633 );
634 let response = AnyResponse {
635 jsonrpc: JSON_RPC_VERSION,
636 id,
637 result: None,
638 error: Some(Error {
639 message: error.to_string(),
640 }),
641 };
642 if let Some(response) = serde_json::to_string(&response).log_err() {
643 outbound_tx.try_send(response).ok();
644 }
645 }
646 }
647 }
648 }),
649 );
650 assert!(
651 prev_handler.is_none(),
652 "registered multiple handlers for the same LSP method"
653 );
654 Subscription::Notification {
655 method,
656 notification_handlers: Some(self.notification_handlers.clone()),
657 }
658 }
659
660 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
661 &self.name
662 }
663
664 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
665 &self.capabilities
666 }
667
668 pub fn server_id(&self) -> LanguageServerId {
669 self.server_id
670 }
671
672 pub fn root_path(&self) -> &PathBuf {
673 &self.root_path
674 }
675
676 pub fn request<T: request::Request>(
677 &self,
678 params: T::Params,
679 ) -> impl Future<Output = Result<T::Result>>
680 where
681 T::Result: 'static + Send,
682 {
683 Self::request_internal::<T>(
684 &self.next_id,
685 &self.response_handlers,
686 &self.outbound_tx,
687 &self.executor,
688 params,
689 )
690 }
691
692 fn request_internal<T: request::Request>(
693 next_id: &AtomicUsize,
694 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
695 outbound_tx: &channel::Sender<String>,
696 executor: &Arc<executor::Background>,
697 params: T::Params,
698 ) -> impl 'static + Future<Output = Result<T::Result>>
699 where
700 T::Result: 'static + Send,
701 {
702 let id = next_id.fetch_add(1, SeqCst);
703 let message = serde_json::to_string(&Request {
704 jsonrpc: JSON_RPC_VERSION,
705 id,
706 method: T::METHOD,
707 params,
708 })
709 .unwrap();
710
711 let (tx, rx) = oneshot::channel();
712 let handle_response = response_handlers
713 .lock()
714 .as_mut()
715 .ok_or_else(|| anyhow!("server shut down"))
716 .map(|handlers| {
717 let executor = executor.clone();
718 handlers.insert(
719 id,
720 Box::new(move |result| {
721 executor
722 .spawn(async move {
723 let response = match result {
724 Ok(response) => serde_json::from_str(&response)
725 .context("failed to deserialize response"),
726 Err(error) => Err(anyhow!("{}", error.message)),
727 };
728 _ = tx.send(response);
729 })
730 .detach();
731 }),
732 );
733 });
734
735 let send = outbound_tx
736 .try_send(message)
737 .context("failed to write to language server's stdin");
738
739 async move {
740 handle_response?;
741 send?;
742 rx.await?
743 }
744 }
745
746 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
747 Self::notify_internal::<T>(&self.outbound_tx, params)
748 }
749
750 fn notify_internal<T: notification::Notification>(
751 outbound_tx: &channel::Sender<String>,
752 params: T::Params,
753 ) -> Result<()> {
754 let message = serde_json::to_string(&Notification {
755 jsonrpc: JSON_RPC_VERSION,
756 method: T::METHOD,
757 params,
758 })
759 .unwrap();
760 outbound_tx.try_send(message)?;
761 Ok(())
762 }
763}
764
765impl Drop for LanguageServer {
766 fn drop(&mut self) {
767 if let Some(shutdown) = self.shutdown() {
768 self.executor.spawn(shutdown).detach();
769 }
770 }
771}
772
773impl Subscription {
774 pub fn detach(&mut self) {
775 match self {
776 Subscription::Notification {
777 notification_handlers,
778 ..
779 } => *notification_handlers = None,
780 Subscription::Io { io_handlers, .. } => *io_handlers = None,
781 }
782 }
783}
784
785impl fmt::Display for LanguageServerId {
786 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
787 self.0.fmt(f)
788 }
789}
790
791impl fmt::Debug for LanguageServer {
792 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
793 f.debug_struct("LanguageServer")
794 .field("id", &self.server_id.0)
795 .field("name", &self.name)
796 .finish_non_exhaustive()
797 }
798}
799
800impl Drop for Subscription {
801 fn drop(&mut self) {
802 match self {
803 Subscription::Notification {
804 method,
805 notification_handlers,
806 } => {
807 if let Some(handlers) = notification_handlers {
808 handlers.lock().remove(method);
809 }
810 }
811 Subscription::Io { id, io_handlers } => {
812 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
813 io_handlers.lock().remove(id);
814 }
815 }
816 }
817 }
818}
819
820#[cfg(any(test, feature = "test-support"))]
821#[derive(Clone)]
822pub struct FakeLanguageServer {
823 pub server: Arc<LanguageServer>,
824 notifications_rx: channel::Receiver<(String, String)>,
825}
826
827#[cfg(any(test, feature = "test-support"))]
828impl LanguageServer {
829 pub fn full_capabilities() -> ServerCapabilities {
830 ServerCapabilities {
831 document_highlight_provider: Some(OneOf::Left(true)),
832 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
833 document_formatting_provider: Some(OneOf::Left(true)),
834 document_range_formatting_provider: Some(OneOf::Left(true)),
835 definition_provider: Some(OneOf::Left(true)),
836 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
837 ..Default::default()
838 }
839 }
840
841 pub fn fake(
842 name: String,
843 capabilities: ServerCapabilities,
844 cx: AsyncAppContext,
845 ) -> (Self, FakeLanguageServer) {
846 let (stdin_writer, stdin_reader) = async_pipe::pipe();
847 let (stdout_writer, stdout_reader) = async_pipe::pipe();
848 let (notifications_tx, notifications_rx) = channel::unbounded();
849
850 let server = Self::new_internal(
851 LanguageServerId(0),
852 stdin_writer,
853 stdout_reader,
854 None,
855 Path::new("/"),
856 None,
857 cx.clone(),
858 |_| {},
859 );
860 let fake = FakeLanguageServer {
861 server: Arc::new(Self::new_internal(
862 LanguageServerId(0),
863 stdout_writer,
864 stdin_reader,
865 None,
866 Path::new("/"),
867 None,
868 cx,
869 move |msg| {
870 notifications_tx
871 .try_send((
872 msg.method.to_string(),
873 msg.params
874 .map(|raw_value| raw_value.get())
875 .unwrap_or("null")
876 .to_string(),
877 ))
878 .ok();
879 },
880 )),
881 notifications_rx,
882 };
883 fake.handle_request::<request::Initialize, _, _>({
884 let capabilities = capabilities;
885 move |_, _| {
886 let capabilities = capabilities.clone();
887 let name = name.clone();
888 async move {
889 Ok(InitializeResult {
890 capabilities,
891 server_info: Some(ServerInfo {
892 name,
893 ..Default::default()
894 }),
895 })
896 }
897 }
898 });
899
900 (server, fake)
901 }
902}
903
904#[cfg(any(test, feature = "test-support"))]
905impl FakeLanguageServer {
906 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
907 self.server.notify::<T>(params).ok();
908 }
909
910 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
911 where
912 T: request::Request,
913 T::Result: 'static + Send,
914 {
915 self.server.executor.start_waiting();
916 self.server.request::<T>(params).await
917 }
918
919 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
920 self.server.executor.start_waiting();
921 self.try_receive_notification::<T>().await.unwrap()
922 }
923
924 pub async fn try_receive_notification<T: notification::Notification>(
925 &mut self,
926 ) -> Option<T::Params> {
927 use futures::StreamExt as _;
928
929 loop {
930 let (method, params) = self.notifications_rx.next().await?;
931 if method == T::METHOD {
932 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
933 } else {
934 log::info!("skipping message in fake language server {:?}", params);
935 }
936 }
937 }
938
939 pub fn handle_request<T, F, Fut>(
940 &self,
941 mut handler: F,
942 ) -> futures::channel::mpsc::UnboundedReceiver<()>
943 where
944 T: 'static + request::Request,
945 T::Params: 'static + Send,
946 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
947 Fut: 'static + Send + Future<Output = Result<T::Result>>,
948 {
949 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
950 self.server.remove_request_handler::<T>();
951 self.server
952 .on_request::<T, _, _>(move |params, cx| {
953 let result = handler(params, cx.clone());
954 let responded_tx = responded_tx.clone();
955 async move {
956 cx.background().simulate_random_delay().await;
957 let result = result.await;
958 responded_tx.unbounded_send(()).ok();
959 result
960 }
961 })
962 .detach();
963 responded_rx
964 }
965
966 pub fn handle_notification<T, F>(
967 &self,
968 mut handler: F,
969 ) -> futures::channel::mpsc::UnboundedReceiver<()>
970 where
971 T: 'static + notification::Notification,
972 T::Params: 'static + Send,
973 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
974 {
975 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
976 self.server.remove_notification_handler::<T>();
977 self.server
978 .on_notification::<T, _>(move |params, cx| {
979 handler(params, cx.clone());
980 handled_tx.unbounded_send(()).ok();
981 })
982 .detach();
983 handled_rx
984 }
985
986 pub fn remove_request_handler<T>(&mut self)
987 where
988 T: 'static + request::Request,
989 {
990 self.server.remove_request_handler::<T>();
991 }
992
993 pub async fn start_progress(&self, token: impl Into<String>) {
994 let token = token.into();
995 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
996 token: NumberOrString::String(token.clone()),
997 })
998 .await
999 .unwrap();
1000 self.notify::<notification::Progress>(ProgressParams {
1001 token: NumberOrString::String(token),
1002 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
1003 });
1004 }
1005
1006 pub fn end_progress(&self, token: impl Into<String>) {
1007 self.notify::<notification::Progress>(ProgressParams {
1008 token: NumberOrString::String(token.into()),
1009 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1010 });
1011 }
1012}
1013
1014#[cfg(test)]
1015mod tests {
1016 use super::*;
1017 use gpui::TestAppContext;
1018
1019 #[ctor::ctor]
1020 fn init_logger() {
1021 if std::env::var("RUST_LOG").is_ok() {
1022 env_logger::init();
1023 }
1024 }
1025
1026 #[gpui::test]
1027 async fn test_fake(cx: &mut TestAppContext) {
1028 let (server, mut fake) =
1029 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
1030
1031 let (message_tx, message_rx) = channel::unbounded();
1032 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1033 server
1034 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1035 message_tx.try_send(params).unwrap()
1036 })
1037 .detach();
1038 server
1039 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1040 diagnostics_tx.try_send(params).unwrap()
1041 })
1042 .detach();
1043
1044 let server = server.initialize(None).await.unwrap();
1045 server
1046 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1047 text_document: TextDocumentItem::new(
1048 Url::from_str("file://a/b").unwrap(),
1049 "rust".to_string(),
1050 0,
1051 "".to_string(),
1052 ),
1053 })
1054 .unwrap();
1055 assert_eq!(
1056 fake.receive_notification::<notification::DidOpenTextDocument>()
1057 .await
1058 .text_document
1059 .uri
1060 .as_str(),
1061 "file://a/b"
1062 );
1063
1064 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1065 typ: MessageType::ERROR,
1066 message: "ok".to_string(),
1067 });
1068 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1069 uri: Url::from_str("file://b/c").unwrap(),
1070 version: Some(5),
1071 diagnostics: vec![],
1072 });
1073 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1074 assert_eq!(
1075 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1076 "file://b/c"
1077 );
1078
1079 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1080
1081 drop(server);
1082 fake.receive_notification::<notification::Exit>().await;
1083 }
1084}