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<&str, 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()));
313 } else {
314 handler(Ok("null"));
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 ..Default::default()
392 }),
393 text_document: Some(TextDocumentClientCapabilities {
394 definition: Some(GotoCapability {
395 link_support: Some(true),
396 ..Default::default()
397 }),
398 code_action: Some(CodeActionClientCapabilities {
399 code_action_literal_support: Some(CodeActionLiteralSupport {
400 code_action_kind: CodeActionKindLiteralSupport {
401 value_set: vec![
402 CodeActionKind::REFACTOR.as_str().into(),
403 CodeActionKind::QUICKFIX.as_str().into(),
404 CodeActionKind::SOURCE.as_str().into(),
405 ],
406 },
407 }),
408 data_support: Some(true),
409 resolve_support: Some(CodeActionCapabilityResolveSupport {
410 properties: vec!["edit".to_string(), "command".to_string()],
411 }),
412 ..Default::default()
413 }),
414 completion: Some(CompletionClientCapabilities {
415 completion_item: Some(CompletionItemCapability {
416 snippet_support: Some(true),
417 resolve_support: Some(CompletionItemCapabilityResolveSupport {
418 properties: vec!["additionalTextEdits".to_string()],
419 }),
420 ..Default::default()
421 }),
422 ..Default::default()
423 }),
424 rename: Some(RenameClientCapabilities {
425 prepare_support: Some(true),
426 ..Default::default()
427 }),
428 hover: Some(HoverClientCapabilities {
429 content_format: Some(vec![MarkupKind::Markdown]),
430 ..Default::default()
431 }),
432 ..Default::default()
433 }),
434 experimental: Some(json!({
435 "serverStatusNotification": true,
436 })),
437 window: Some(WindowClientCapabilities {
438 work_done_progress: Some(true),
439 ..Default::default()
440 }),
441 ..Default::default()
442 },
443 trace: Default::default(),
444 workspace_folders: Some(vec![WorkspaceFolder {
445 uri: root_uri,
446 name: Default::default(),
447 }]),
448 client_info: Default::default(),
449 locale: Default::default(),
450 };
451
452 let response = self.request::<request::Initialize>(params).await?;
453 if let Some(info) = response.server_info {
454 self.name = info.name;
455 }
456 self.capabilities = response.capabilities;
457
458 self.notify::<notification::Initialized>(InitializedParams {})?;
459 Ok(Arc::new(self))
460 }
461
462 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
463 if let Some(tasks) = self.io_tasks.lock().take() {
464 let response_handlers = self.response_handlers.clone();
465 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
466 let outbound_tx = self.outbound_tx.clone();
467 let mut output_done = self.output_done_rx.lock().take().unwrap();
468 let shutdown_request = Self::request_internal::<request::Shutdown>(
469 &next_id,
470 &response_handlers,
471 &outbound_tx,
472 (),
473 );
474 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
475 outbound_tx.close();
476 Some(
477 async move {
478 log::debug!("language server shutdown started");
479 shutdown_request.await?;
480 response_handlers.lock().take();
481 exit?;
482 output_done.recv().await;
483 log::debug!("language server shutdown finished");
484 drop(tasks);
485 anyhow::Ok(())
486 }
487 .log_err(),
488 )
489 } else {
490 None
491 }
492 }
493
494 #[must_use]
495 pub fn on_notification<T, F>(&self, f: F) -> Subscription
496 where
497 T: notification::Notification,
498 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
499 {
500 self.on_custom_notification(T::METHOD, f)
501 }
502
503 #[must_use]
504 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
505 where
506 T: request::Request,
507 T::Params: 'static + Send,
508 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
509 Fut: 'static + Future<Output = Result<T::Result>>,
510 {
511 self.on_custom_request(T::METHOD, f)
512 }
513
514 #[must_use]
515 pub fn on_io<F>(&self, f: F) -> Subscription
516 where
517 F: 'static + Send + FnMut(bool, &str),
518 {
519 let id = self.next_id.fetch_add(1, SeqCst);
520 self.io_handlers.lock().insert(id, Box::new(f));
521 Subscription::Io {
522 id,
523 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
524 }
525 }
526
527 pub fn remove_request_handler<T: request::Request>(&self) {
528 self.notification_handlers.lock().remove(T::METHOD);
529 }
530
531 pub fn remove_notification_handler<T: notification::Notification>(&self) {
532 self.notification_handlers.lock().remove(T::METHOD);
533 }
534
535 #[must_use]
536 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
537 where
538 F: 'static + Send + FnMut(Params, AsyncAppContext),
539 Params: DeserializeOwned,
540 {
541 let prev_handler = self.notification_handlers.lock().insert(
542 method,
543 Box::new(move |_, params, cx| {
544 if let Some(params) = serde_json::from_str(params).log_err() {
545 f(params, cx);
546 }
547 }),
548 );
549 assert!(
550 prev_handler.is_none(),
551 "registered multiple handlers for the same LSP method"
552 );
553 Subscription::Notification {
554 method,
555 notification_handlers: Some(self.notification_handlers.clone()),
556 }
557 }
558
559 #[must_use]
560 pub fn on_custom_request<Params, Res, Fut, F>(
561 &self,
562 method: &'static str,
563 mut f: F,
564 ) -> Subscription
565 where
566 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
567 Fut: 'static + Future<Output = Result<Res>>,
568 Params: DeserializeOwned + Send + 'static,
569 Res: Serialize,
570 {
571 let outbound_tx = self.outbound_tx.clone();
572 let prev_handler = self.notification_handlers.lock().insert(
573 method,
574 Box::new(move |id, params, cx| {
575 if let Some(id) = id {
576 match serde_json::from_str(params) {
577 Ok(params) => {
578 let response = f(params, cx.clone());
579 cx.foreground()
580 .spawn({
581 let outbound_tx = outbound_tx.clone();
582 async move {
583 let response = match response.await {
584 Ok(result) => Response {
585 jsonrpc: JSON_RPC_VERSION,
586 id,
587 result: Some(result),
588 error: None,
589 },
590 Err(error) => Response {
591 jsonrpc: JSON_RPC_VERSION,
592 id,
593 result: None,
594 error: Some(Error {
595 message: error.to_string(),
596 }),
597 },
598 };
599 if let Some(response) =
600 serde_json::to_string(&response).log_err()
601 {
602 outbound_tx.try_send(response).ok();
603 }
604 }
605 })
606 .detach();
607 }
608 Err(error) => {
609 log::error!(
610 "error deserializing {} request: {:?}, message: {:?}",
611 method,
612 error,
613 params
614 );
615 let response = AnyResponse {
616 jsonrpc: JSON_RPC_VERSION,
617 id,
618 result: None,
619 error: Some(Error {
620 message: error.to_string(),
621 }),
622 };
623 if let Some(response) = serde_json::to_string(&response).log_err() {
624 outbound_tx.try_send(response).ok();
625 }
626 }
627 }
628 }
629 }),
630 );
631 assert!(
632 prev_handler.is_none(),
633 "registered multiple handlers for the same LSP method"
634 );
635 Subscription::Notification {
636 method,
637 notification_handlers: Some(self.notification_handlers.clone()),
638 }
639 }
640
641 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
642 &self.name
643 }
644
645 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
646 &self.capabilities
647 }
648
649 pub fn server_id(&self) -> LanguageServerId {
650 self.server_id
651 }
652
653 pub fn root_path(&self) -> &PathBuf {
654 &self.root_path
655 }
656
657 pub fn request<T: request::Request>(
658 &self,
659 params: T::Params,
660 ) -> impl Future<Output = Result<T::Result>>
661 where
662 T::Result: 'static + Send,
663 {
664 Self::request_internal::<T>(
665 &self.next_id,
666 &self.response_handlers,
667 &self.outbound_tx,
668 params,
669 )
670 }
671
672 fn request_internal<T: request::Request>(
673 next_id: &AtomicUsize,
674 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
675 outbound_tx: &channel::Sender<String>,
676 params: T::Params,
677 ) -> impl 'static + Future<Output = Result<T::Result>>
678 where
679 T::Result: 'static + Send,
680 {
681 let id = next_id.fetch_add(1, SeqCst);
682 let message = serde_json::to_string(&Request {
683 jsonrpc: JSON_RPC_VERSION,
684 id,
685 method: T::METHOD,
686 params,
687 })
688 .unwrap();
689
690 let (tx, rx) = oneshot::channel();
691 let handle_response = response_handlers
692 .lock()
693 .as_mut()
694 .ok_or_else(|| anyhow!("server shut down"))
695 .map(|handlers| {
696 handlers.insert(
697 id,
698 Box::new(move |result| {
699 let response = match result {
700 Ok(response) => serde_json::from_str(response)
701 .context("failed to deserialize response"),
702 Err(error) => Err(anyhow!("{}", error.message)),
703 };
704 let _ = tx.send(response);
705 }),
706 );
707 });
708
709 let send = outbound_tx
710 .try_send(message)
711 .context("failed to write to language server's stdin");
712
713 async move {
714 handle_response?;
715 send?;
716 rx.await?
717 }
718 }
719
720 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
721 Self::notify_internal::<T>(&self.outbound_tx, params)
722 }
723
724 fn notify_internal<T: notification::Notification>(
725 outbound_tx: &channel::Sender<String>,
726 params: T::Params,
727 ) -> Result<()> {
728 let message = serde_json::to_string(&Notification {
729 jsonrpc: JSON_RPC_VERSION,
730 method: T::METHOD,
731 params,
732 })
733 .unwrap();
734 outbound_tx.try_send(message)?;
735 Ok(())
736 }
737}
738
739impl Drop for LanguageServer {
740 fn drop(&mut self) {
741 if let Some(shutdown) = self.shutdown() {
742 self.executor.spawn(shutdown).detach();
743 }
744 }
745}
746
747impl Subscription {
748 pub fn detach(&mut self) {
749 match self {
750 Subscription::Notification {
751 notification_handlers,
752 ..
753 } => *notification_handlers = None,
754 Subscription::Io { io_handlers, .. } => *io_handlers = None,
755 }
756 }
757}
758
759impl fmt::Display for LanguageServerId {
760 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
761 self.0.fmt(f)
762 }
763}
764
765impl fmt::Debug for LanguageServer {
766 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
767 f.debug_struct("LanguageServer")
768 .field("id", &self.server_id.0)
769 .field("name", &self.name)
770 .finish_non_exhaustive()
771 }
772}
773
774impl Drop for Subscription {
775 fn drop(&mut self) {
776 match self {
777 Subscription::Notification {
778 method,
779 notification_handlers,
780 } => {
781 if let Some(handlers) = notification_handlers {
782 handlers.lock().remove(method);
783 }
784 }
785 Subscription::Io { id, io_handlers } => {
786 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
787 io_handlers.lock().remove(id);
788 }
789 }
790 }
791 }
792}
793
794#[cfg(any(test, feature = "test-support"))]
795#[derive(Clone)]
796pub struct FakeLanguageServer {
797 pub server: Arc<LanguageServer>,
798 notifications_rx: channel::Receiver<(String, String)>,
799}
800
801#[cfg(any(test, feature = "test-support"))]
802impl LanguageServer {
803 pub fn full_capabilities() -> ServerCapabilities {
804 ServerCapabilities {
805 document_highlight_provider: Some(OneOf::Left(true)),
806 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
807 document_formatting_provider: Some(OneOf::Left(true)),
808 document_range_formatting_provider: Some(OneOf::Left(true)),
809 definition_provider: Some(OneOf::Left(true)),
810 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
811 ..Default::default()
812 }
813 }
814
815 pub fn fake(
816 name: String,
817 capabilities: ServerCapabilities,
818 cx: AsyncAppContext,
819 ) -> (Self, FakeLanguageServer) {
820 let (stdin_writer, stdin_reader) = async_pipe::pipe();
821 let (stdout_writer, stdout_reader) = async_pipe::pipe();
822 let (notifications_tx, notifications_rx) = channel::unbounded();
823
824 let server = Self::new_internal(
825 LanguageServerId(0),
826 stdin_writer,
827 stdout_reader,
828 None,
829 Path::new("/"),
830 None,
831 cx.clone(),
832 |_| {},
833 );
834 let fake = FakeLanguageServer {
835 server: Arc::new(Self::new_internal(
836 LanguageServerId(0),
837 stdout_writer,
838 stdin_reader,
839 None,
840 Path::new("/"),
841 None,
842 cx,
843 move |msg| {
844 notifications_tx
845 .try_send((
846 msg.method.to_string(),
847 msg.params
848 .map(|raw_value| raw_value.get())
849 .unwrap_or("null")
850 .to_string(),
851 ))
852 .ok();
853 },
854 )),
855 notifications_rx,
856 };
857 fake.handle_request::<request::Initialize, _, _>({
858 let capabilities = capabilities;
859 move |_, _| {
860 let capabilities = capabilities.clone();
861 let name = name.clone();
862 async move {
863 Ok(InitializeResult {
864 capabilities,
865 server_info: Some(ServerInfo {
866 name,
867 ..Default::default()
868 }),
869 })
870 }
871 }
872 });
873
874 (server, fake)
875 }
876}
877
878#[cfg(any(test, feature = "test-support"))]
879impl FakeLanguageServer {
880 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
881 self.server.notify::<T>(params).ok();
882 }
883
884 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
885 where
886 T: request::Request,
887 T::Result: 'static + Send,
888 {
889 self.server.executor.start_waiting();
890 self.server.request::<T>(params).await
891 }
892
893 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
894 self.server.executor.start_waiting();
895 self.try_receive_notification::<T>().await.unwrap()
896 }
897
898 pub async fn try_receive_notification<T: notification::Notification>(
899 &mut self,
900 ) -> Option<T::Params> {
901 use futures::StreamExt as _;
902
903 loop {
904 let (method, params) = self.notifications_rx.next().await?;
905 if method == T::METHOD {
906 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
907 } else {
908 log::info!("skipping message in fake language server {:?}", params);
909 }
910 }
911 }
912
913 pub fn handle_request<T, F, Fut>(
914 &self,
915 mut handler: F,
916 ) -> futures::channel::mpsc::UnboundedReceiver<()>
917 where
918 T: 'static + request::Request,
919 T::Params: 'static + Send,
920 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
921 Fut: 'static + Send + Future<Output = Result<T::Result>>,
922 {
923 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
924 self.server.remove_request_handler::<T>();
925 self.server
926 .on_request::<T, _, _>(move |params, cx| {
927 let result = handler(params, cx.clone());
928 let responded_tx = responded_tx.clone();
929 async move {
930 cx.background().simulate_random_delay().await;
931 let result = result.await;
932 responded_tx.unbounded_send(()).ok();
933 result
934 }
935 })
936 .detach();
937 responded_rx
938 }
939
940 pub fn handle_notification<T, F>(
941 &self,
942 mut handler: F,
943 ) -> futures::channel::mpsc::UnboundedReceiver<()>
944 where
945 T: 'static + notification::Notification,
946 T::Params: 'static + Send,
947 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
948 {
949 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
950 self.server.remove_notification_handler::<T>();
951 self.server
952 .on_notification::<T, _>(move |params, cx| {
953 handler(params, cx.clone());
954 handled_tx.unbounded_send(()).ok();
955 })
956 .detach();
957 handled_rx
958 }
959
960 pub fn remove_request_handler<T>(&mut self)
961 where
962 T: 'static + request::Request,
963 {
964 self.server.remove_request_handler::<T>();
965 }
966
967 pub async fn start_progress(&self, token: impl Into<String>) {
968 let token = token.into();
969 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
970 token: NumberOrString::String(token.clone()),
971 })
972 .await
973 .unwrap();
974 self.notify::<notification::Progress>(ProgressParams {
975 token: NumberOrString::String(token),
976 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
977 });
978 }
979
980 pub fn end_progress(&self, token: impl Into<String>) {
981 self.notify::<notification::Progress>(ProgressParams {
982 token: NumberOrString::String(token.into()),
983 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
984 });
985 }
986}
987
988#[cfg(test)]
989mod tests {
990 use super::*;
991 use gpui::TestAppContext;
992
993 #[ctor::ctor]
994 fn init_logger() {
995 if std::env::var("RUST_LOG").is_ok() {
996 env_logger::init();
997 }
998 }
999
1000 #[gpui::test]
1001 async fn test_fake(cx: &mut TestAppContext) {
1002 let (server, mut fake) =
1003 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
1004
1005 let (message_tx, message_rx) = channel::unbounded();
1006 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1007 server
1008 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1009 message_tx.try_send(params).unwrap()
1010 })
1011 .detach();
1012 server
1013 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1014 diagnostics_tx.try_send(params).unwrap()
1015 })
1016 .detach();
1017
1018 let server = server.initialize(None).await.unwrap();
1019 server
1020 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1021 text_document: TextDocumentItem::new(
1022 Url::from_str("file://a/b").unwrap(),
1023 "rust".to_string(),
1024 0,
1025 "".to_string(),
1026 ),
1027 })
1028 .unwrap();
1029 assert_eq!(
1030 fake.receive_notification::<notification::DidOpenTextDocument>()
1031 .await
1032 .text_document
1033 .uri
1034 .as_str(),
1035 "file://a/b"
1036 );
1037
1038 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1039 typ: MessageType::ERROR,
1040 message: "ok".to_string(),
1041 });
1042 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1043 uri: Url::from_str("file://b/c").unwrap(),
1044 version: Some(5),
1045 diagnostics: vec![],
1046 });
1047 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1048 assert_eq!(
1049 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1050 "file://b/c"
1051 );
1052
1053 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1054
1055 drop(server);
1056 fake.receive_notification::<notification::Exit>().await;
1057 }
1058}