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