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