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, FutureExt};
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 time::{Duration, Instant},
30};
31use std::{path::Path, process::Stdio};
32use util::{ResultExt, TryFutureExt};
33
34const JSON_RPC_VERSION: &str = "2.0";
35const CONTENT_LEN_HEADER: &str = "Content-Length: ";
36const LSP_REQUEST_TIMEOUT: Duration = Duration::from_secs(60 * 2);
37
38type NotificationHandler = Box<dyn Send + FnMut(Option<usize>, &str, AsyncAppContext)>;
39type ResponseHandler = Box<dyn Send + FnOnce(Result<String, Error>)>;
40type IoHandler = Box<dyn Send + FnMut(IoKind, &str)>;
41
42#[derive(Debug, Clone, Copy)]
43pub enum IoKind {
44 StdOut,
45 StdIn,
46 StdErr,
47}
48
49#[derive(Debug, Clone, Deserialize)]
50pub struct LanguageServerBinary {
51 pub path: PathBuf,
52 pub arguments: Vec<OsString>,
53}
54
55pub struct LanguageServer {
56 server_id: LanguageServerId,
57 next_id: AtomicUsize,
58 outbound_tx: channel::Sender<String>,
59 name: String,
60 capabilities: ServerCapabilities,
61 code_action_kinds: Option<Vec<CodeActionKind>>,
62 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
63 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
64 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
65 executor: Arc<executor::Background>,
66 #[allow(clippy::type_complexity)]
67 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
68 output_done_rx: Mutex<Option<barrier::Receiver>>,
69 root_path: PathBuf,
70 _server: Option<Mutex<Child>>,
71}
72
73#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
74#[repr(transparent)]
75pub struct LanguageServerId(pub usize);
76
77pub enum Subscription {
78 Notification {
79 method: &'static str,
80 notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
81 },
82 Io {
83 id: usize,
84 io_handlers: Option<Weak<Mutex<HashMap<usize, IoHandler>>>>,
85 },
86}
87
88#[derive(Serialize, Deserialize)]
89pub struct Request<'a, T> {
90 jsonrpc: &'static str,
91 id: usize,
92 method: &'a str,
93 params: T,
94}
95
96#[derive(Serialize, Deserialize)]
97struct AnyResponse<'a> {
98 jsonrpc: &'a str,
99 id: usize,
100 #[serde(default)]
101 error: Option<Error>,
102 #[serde(borrow)]
103 result: Option<&'a RawValue>,
104}
105
106#[derive(Serialize)]
107struct Response<T> {
108 jsonrpc: &'static str,
109 id: usize,
110 result: Option<T>,
111 error: Option<Error>,
112}
113
114#[derive(Serialize, Deserialize)]
115struct Notification<'a, T> {
116 jsonrpc: &'static str,
117 #[serde(borrow)]
118 method: &'a str,
119 params: T,
120}
121
122#[derive(Debug, Clone, Deserialize)]
123struct AnyNotification<'a> {
124 #[serde(default)]
125 id: Option<usize>,
126 #[serde(borrow)]
127 method: &'a str,
128 #[serde(borrow, default)]
129 params: Option<&'a RawValue>,
130}
131
132#[derive(Debug, Serialize, Deserialize)]
133struct Error {
134 message: String,
135}
136
137impl LanguageServer {
138 pub fn new(
139 server_id: LanguageServerId,
140 binary: LanguageServerBinary,
141 root_path: &Path,
142 code_action_kinds: Option<Vec<CodeActionKind>>,
143 cx: AsyncAppContext,
144 ) -> Result<Self> {
145 let working_dir = if root_path.is_dir() {
146 root_path
147 } else {
148 root_path.parent().unwrap_or_else(|| Path::new("/"))
149 };
150
151 let mut server = process::Command::new(&binary.path)
152 .current_dir(working_dir)
153 .args(binary.arguments)
154 .stdin(Stdio::piped())
155 .stdout(Stdio::piped())
156 .stderr(Stdio::piped())
157 .kill_on_drop(true)
158 .spawn()?;
159
160 let stdin = server.stdin.take().unwrap();
161 let stdout = server.stdout.take().unwrap();
162 let stderr = server.stderr.take().unwrap();
163 let mut server = Self::new_internal(
164 server_id.clone(),
165 stdin,
166 stdout,
167 Some(stderr),
168 Some(server),
169 root_path,
170 code_action_kinds,
171 cx,
172 move |notification| {
173 log::info!(
174 "{} unhandled notification {}:\n{}",
175 server_id,
176 notification.method,
177 serde_json::to_string_pretty(
178 ¬ification
179 .params
180 .and_then(|params| Value::from_str(params.get()).ok())
181 .unwrap_or(Value::Null)
182 )
183 .unwrap(),
184 );
185 },
186 );
187
188 if let Some(name) = binary.path.file_name() {
189 server.name = name.to_string_lossy().to_string();
190 }
191
192 Ok(server)
193 }
194
195 fn new_internal<Stdin, Stdout, Stderr, F>(
196 server_id: LanguageServerId,
197 stdin: Stdin,
198 stdout: Stdout,
199 stderr: Option<Stderr>,
200 server: Option<Child>,
201 root_path: &Path,
202 code_action_kinds: Option<Vec<CodeActionKind>>,
203 cx: AsyncAppContext,
204 on_unhandled_notification: F,
205 ) -> Self
206 where
207 Stdin: AsyncWrite + Unpin + Send + 'static,
208 Stdout: AsyncRead + Unpin + Send + 'static,
209 Stderr: AsyncRead + Unpin + Send + 'static,
210 F: FnMut(AnyNotification) + 'static + Send + Clone,
211 {
212 let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
213 let (output_done_tx, output_done_rx) = barrier::channel();
214 let notification_handlers =
215 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
216 let response_handlers =
217 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
218 let io_handlers = Arc::new(Mutex::new(HashMap::default()));
219
220 let stdout_input_task = cx.spawn(|cx| {
221 {
222 Self::handle_input(
223 stdout,
224 on_unhandled_notification.clone(),
225 notification_handlers.clone(),
226 response_handlers.clone(),
227 io_handlers.clone(),
228 cx,
229 )
230 }
231 .log_err()
232 });
233 let stderr_input_task = stderr
234 .map(|stderr| cx.spawn(|_| Self::handle_stderr(stderr, io_handlers.clone()).log_err()))
235 .unwrap_or_else(|| Task::Ready(Some(None)));
236 let input_task = cx.spawn(|_| async move {
237 let (stdout, stderr) = futures::join!(stdout_input_task, stderr_input_task);
238 stdout.or(stderr)
239 });
240 let output_task = cx.background().spawn({
241 Self::handle_output(
242 stdin,
243 outbound_rx,
244 output_done_tx,
245 response_handlers.clone(),
246 io_handlers.clone(),
247 )
248 .log_err()
249 });
250
251 Self {
252 server_id,
253 notification_handlers,
254 response_handlers,
255 io_handlers,
256 name: Default::default(),
257 capabilities: Default::default(),
258 code_action_kinds,
259 next_id: Default::default(),
260 outbound_tx,
261 executor: cx.background(),
262 io_tasks: Mutex::new(Some((input_task, output_task))),
263 output_done_rx: Mutex::new(Some(output_done_rx)),
264 root_path: root_path.to_path_buf(),
265 _server: server.map(|server| Mutex::new(server)),
266 }
267 }
268
269 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
270 self.code_action_kinds.clone()
271 }
272
273 async fn handle_input<Stdout, F>(
274 stdout: Stdout,
275 mut on_unhandled_notification: F,
276 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
277 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
278 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
279 cx: AsyncAppContext,
280 ) -> anyhow::Result<()>
281 where
282 Stdout: AsyncRead + Unpin + Send + 'static,
283 F: FnMut(AnyNotification) + 'static + Send,
284 {
285 let mut stdout = BufReader::new(stdout);
286 let _clear_response_handlers = util::defer({
287 let response_handlers = response_handlers.clone();
288 move || {
289 response_handlers.lock().take();
290 }
291 });
292 let mut buffer = Vec::new();
293 loop {
294 buffer.clear();
295 stdout.read_until(b'\n', &mut buffer).await?;
296 stdout.read_until(b'\n', &mut buffer).await?;
297 let header = std::str::from_utf8(&buffer)?;
298 let message_len: usize = header
299 .strip_prefix(CONTENT_LEN_HEADER)
300 .ok_or_else(|| anyhow!("invalid LSP message header {header:?}"))?
301 .trim_end()
302 .parse()?;
303
304 buffer.resize(message_len, 0);
305 stdout.read_exact(&mut buffer).await?;
306
307 if let Ok(message) = str::from_utf8(&buffer) {
308 log::trace!("incoming message: {}", message);
309 for handler in io_handlers.lock().values_mut() {
310 handler(IoKind::StdOut, message);
311 }
312 }
313
314 if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
315 if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
316 handler(
317 msg.id,
318 &msg.params.map(|params| params.get()).unwrap_or("null"),
319 cx.clone(),
320 );
321 } else {
322 on_unhandled_notification(msg);
323 }
324 } else if let Ok(AnyResponse {
325 id, error, result, ..
326 }) = serde_json::from_slice(&buffer)
327 {
328 if let Some(handler) = response_handlers
329 .lock()
330 .as_mut()
331 .and_then(|handlers| handlers.remove(&id))
332 {
333 if let Some(error) = error {
334 handler(Err(error));
335 } else if let Some(result) = result {
336 handler(Ok(result.get().into()));
337 } else {
338 handler(Ok("null".into()));
339 }
340 }
341 } else {
342 warn!(
343 "failed to deserialize LSP message:\n{}",
344 std::str::from_utf8(&buffer)?
345 );
346 }
347
348 // Don't starve the main thread when receiving lots of messages at once.
349 smol::future::yield_now().await;
350 }
351 }
352
353 async fn handle_stderr<Stderr>(
354 stderr: Stderr,
355 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
356 ) -> anyhow::Result<()>
357 where
358 Stderr: AsyncRead + Unpin + Send + 'static,
359 {
360 let mut stderr = BufReader::new(stderr);
361 let mut buffer = Vec::new();
362 loop {
363 buffer.clear();
364 stderr.read_until(b'\n', &mut buffer).await?;
365 if let Ok(message) = str::from_utf8(&buffer) {
366 log::trace!("incoming stderr message:{message}");
367 for handler in io_handlers.lock().values_mut() {
368 handler(IoKind::StdErr, message);
369 }
370 }
371
372 // Don't starve the main thread when receiving lots of messages at once.
373 smol::future::yield_now().await;
374 }
375 }
376
377 async fn handle_output<Stdin>(
378 stdin: Stdin,
379 outbound_rx: channel::Receiver<String>,
380 output_done_tx: barrier::Sender,
381 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
382 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
383 ) -> anyhow::Result<()>
384 where
385 Stdin: AsyncWrite + Unpin + Send + 'static,
386 {
387 let mut stdin = BufWriter::new(stdin);
388 let _clear_response_handlers = util::defer({
389 let response_handlers = response_handlers.clone();
390 move || {
391 response_handlers.lock().take();
392 }
393 });
394 let mut content_len_buffer = Vec::new();
395 while let Ok(message) = outbound_rx.recv().await {
396 log::trace!("outgoing message:{}", message);
397 for handler in io_handlers.lock().values_mut() {
398 handler(IoKind::StdIn, &message);
399 }
400
401 content_len_buffer.clear();
402 write!(content_len_buffer, "{}", message.len()).unwrap();
403 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
404 stdin.write_all(&content_len_buffer).await?;
405 stdin.write_all("\r\n\r\n".as_bytes()).await?;
406 stdin.write_all(message.as_bytes()).await?;
407 stdin.flush().await?;
408 }
409 drop(output_done_tx);
410 Ok(())
411 }
412
413 /// Initializes a language server.
414 /// Note that `options` is used directly to construct [`InitializeParams`],
415 /// which is why it is owned.
416 pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
417 let root_uri = Url::from_file_path(&self.root_path).unwrap();
418 #[allow(deprecated)]
419 let params = InitializeParams {
420 process_id: Default::default(),
421 root_path: Default::default(),
422 root_uri: Some(root_uri.clone()),
423 initialization_options: options,
424 capabilities: ClientCapabilities {
425 workspace: Some(WorkspaceClientCapabilities {
426 configuration: Some(true),
427 did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
428 dynamic_registration: Some(true),
429 relative_pattern_support: Some(true),
430 }),
431 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
432 dynamic_registration: Some(true),
433 }),
434 workspace_folders: Some(true),
435 symbol: Some(WorkspaceSymbolClientCapabilities {
436 resolve_support: None,
437 ..WorkspaceSymbolClientCapabilities::default()
438 }),
439 inlay_hint: Some(InlayHintWorkspaceClientCapabilities {
440 refresh_support: Some(true),
441 }),
442 ..Default::default()
443 }),
444 text_document: Some(TextDocumentClientCapabilities {
445 definition: Some(GotoCapability {
446 link_support: Some(true),
447 ..Default::default()
448 }),
449 code_action: Some(CodeActionClientCapabilities {
450 code_action_literal_support: Some(CodeActionLiteralSupport {
451 code_action_kind: CodeActionKindLiteralSupport {
452 value_set: vec![
453 CodeActionKind::REFACTOR.as_str().into(),
454 CodeActionKind::QUICKFIX.as_str().into(),
455 CodeActionKind::SOURCE.as_str().into(),
456 ],
457 },
458 }),
459 data_support: Some(true),
460 resolve_support: Some(CodeActionCapabilityResolveSupport {
461 properties: vec!["edit".to_string(), "command".to_string()],
462 }),
463 ..Default::default()
464 }),
465 completion: Some(CompletionClientCapabilities {
466 completion_item: Some(CompletionItemCapability {
467 snippet_support: Some(true),
468 resolve_support: Some(CompletionItemCapabilityResolveSupport {
469 properties: vec![
470 "documentation".to_string(),
471 "additionalTextEdits".to_string(),
472 ],
473 }),
474 ..Default::default()
475 }),
476 completion_list: Some(CompletionListCapability {
477 item_defaults: Some(vec![
478 "commitCharacters".to_owned(),
479 "editRange".to_owned(),
480 "insertTextMode".to_owned(),
481 "data".to_owned(),
482 ]),
483 }),
484 ..Default::default()
485 }),
486 rename: Some(RenameClientCapabilities {
487 prepare_support: Some(true),
488 ..Default::default()
489 }),
490 hover: Some(HoverClientCapabilities {
491 content_format: Some(vec![MarkupKind::Markdown]),
492 ..Default::default()
493 }),
494 inlay_hint: Some(InlayHintClientCapabilities {
495 resolve_support: Some(InlayHintResolveClientCapabilities {
496 properties: vec![
497 "textEdits".to_string(),
498 "tooltip".to_string(),
499 "label.tooltip".to_string(),
500 "label.location".to_string(),
501 "label.command".to_string(),
502 ],
503 }),
504 dynamic_registration: Some(false),
505 }),
506 ..Default::default()
507 }),
508 experimental: Some(json!({
509 "serverStatusNotification": true,
510 })),
511 window: Some(WindowClientCapabilities {
512 work_done_progress: Some(true),
513 ..Default::default()
514 }),
515 ..Default::default()
516 },
517 trace: Default::default(),
518 workspace_folders: Some(vec![WorkspaceFolder {
519 uri: root_uri,
520 name: Default::default(),
521 }]),
522 client_info: Default::default(),
523 locale: Default::default(),
524 };
525
526 let response = self.request::<request::Initialize>(params).await?;
527 if let Some(info) = response.server_info {
528 self.name = info.name;
529 }
530 self.capabilities = response.capabilities;
531
532 self.notify::<notification::Initialized>(InitializedParams {})?;
533 Ok(Arc::new(self))
534 }
535
536 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
537 if let Some(tasks) = self.io_tasks.lock().take() {
538 let response_handlers = self.response_handlers.clone();
539 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
540 let outbound_tx = self.outbound_tx.clone();
541 let executor = self.executor.clone();
542 let mut output_done = self.output_done_rx.lock().take().unwrap();
543 let shutdown_request = Self::request_internal::<request::Shutdown>(
544 &next_id,
545 &response_handlers,
546 &outbound_tx,
547 &executor,
548 (),
549 );
550 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
551 outbound_tx.close();
552 Some(
553 async move {
554 log::debug!("language server shutdown started");
555 shutdown_request.await?;
556 response_handlers.lock().take();
557 exit?;
558 output_done.recv().await;
559 log::debug!("language server shutdown finished");
560 drop(tasks);
561 anyhow::Ok(())
562 }
563 .log_err(),
564 )
565 } else {
566 None
567 }
568 }
569
570 #[must_use]
571 pub fn on_notification<T, F>(&self, f: F) -> Subscription
572 where
573 T: notification::Notification,
574 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
575 {
576 self.on_custom_notification(T::METHOD, f)
577 }
578
579 #[must_use]
580 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
581 where
582 T: request::Request,
583 T::Params: 'static + Send,
584 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
585 Fut: 'static + Future<Output = Result<T::Result>>,
586 {
587 self.on_custom_request(T::METHOD, f)
588 }
589
590 #[must_use]
591 pub fn on_io<F>(&self, f: F) -> Subscription
592 where
593 F: 'static + Send + FnMut(IoKind, &str),
594 {
595 let id = self.next_id.fetch_add(1, SeqCst);
596 self.io_handlers.lock().insert(id, Box::new(f));
597 Subscription::Io {
598 id,
599 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
600 }
601 }
602
603 pub fn remove_request_handler<T: request::Request>(&self) {
604 self.notification_handlers.lock().remove(T::METHOD);
605 }
606
607 pub fn remove_notification_handler<T: notification::Notification>(&self) {
608 self.notification_handlers.lock().remove(T::METHOD);
609 }
610
611 pub fn has_notification_handler<T: notification::Notification>(&self) -> bool {
612 self.notification_handlers.lock().contains_key(T::METHOD)
613 }
614
615 #[must_use]
616 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
617 where
618 F: 'static + Send + FnMut(Params, AsyncAppContext),
619 Params: DeserializeOwned,
620 {
621 let prev_handler = self.notification_handlers.lock().insert(
622 method,
623 Box::new(move |_, params, cx| {
624 if let Some(params) = serde_json::from_str(params).log_err() {
625 f(params, cx);
626 }
627 }),
628 );
629 assert!(
630 prev_handler.is_none(),
631 "registered multiple handlers for the same LSP method"
632 );
633 Subscription::Notification {
634 method,
635 notification_handlers: Some(self.notification_handlers.clone()),
636 }
637 }
638
639 #[must_use]
640 pub fn on_custom_request<Params, Res, Fut, F>(
641 &self,
642 method: &'static str,
643 mut f: F,
644 ) -> Subscription
645 where
646 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
647 Fut: 'static + Future<Output = Result<Res>>,
648 Params: DeserializeOwned + Send + 'static,
649 Res: Serialize,
650 {
651 let outbound_tx = self.outbound_tx.clone();
652 let prev_handler = self.notification_handlers.lock().insert(
653 method,
654 Box::new(move |id, params, cx| {
655 if let Some(id) = id {
656 match serde_json::from_str(params) {
657 Ok(params) => {
658 let response = f(params, cx.clone());
659 cx.foreground()
660 .spawn({
661 let outbound_tx = outbound_tx.clone();
662 async move {
663 let response = match response.await {
664 Ok(result) => Response {
665 jsonrpc: JSON_RPC_VERSION,
666 id,
667 result: Some(result),
668 error: None,
669 },
670 Err(error) => Response {
671 jsonrpc: JSON_RPC_VERSION,
672 id,
673 result: None,
674 error: Some(Error {
675 message: error.to_string(),
676 }),
677 },
678 };
679 if let Some(response) =
680 serde_json::to_string(&response).log_err()
681 {
682 outbound_tx.try_send(response).ok();
683 }
684 }
685 })
686 .detach();
687 }
688
689 Err(error) => {
690 log::error!(
691 "error deserializing {} request: {:?}, message: {:?}",
692 method,
693 error,
694 params
695 );
696 let response = AnyResponse {
697 jsonrpc: JSON_RPC_VERSION,
698 id,
699 result: None,
700 error: Some(Error {
701 message: error.to_string(),
702 }),
703 };
704 if let Some(response) = serde_json::to_string(&response).log_err() {
705 outbound_tx.try_send(response).ok();
706 }
707 }
708 }
709 }
710 }),
711 );
712 assert!(
713 prev_handler.is_none(),
714 "registered multiple handlers for the same LSP method"
715 );
716 Subscription::Notification {
717 method,
718 notification_handlers: Some(self.notification_handlers.clone()),
719 }
720 }
721
722 pub fn name(&self) -> &str {
723 &self.name
724 }
725
726 pub fn capabilities(&self) -> &ServerCapabilities {
727 &self.capabilities
728 }
729
730 pub fn server_id(&self) -> LanguageServerId {
731 self.server_id
732 }
733
734 pub fn root_path(&self) -> &PathBuf {
735 &self.root_path
736 }
737
738 pub fn request<T: request::Request>(
739 &self,
740 params: T::Params,
741 ) -> impl Future<Output = Result<T::Result>>
742 where
743 T::Result: 'static + Send,
744 {
745 Self::request_internal::<T>(
746 &self.next_id,
747 &self.response_handlers,
748 &self.outbound_tx,
749 &self.executor,
750 params,
751 )
752 }
753
754 // some child of string literal (be it "" or ``) which is the child of an attribute
755
756 // <Foo className="bar" />
757 // <Foo className={`bar`} />
758 // <Foo className={something + "bar"} />
759 // <Foo className={something + "bar"} />
760 // const classes = "awesome ";
761 // <Foo className={classes} />
762
763 fn request_internal<T: request::Request>(
764 next_id: &AtomicUsize,
765 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
766 outbound_tx: &channel::Sender<String>,
767 executor: &Arc<executor::Background>,
768 params: T::Params,
769 ) -> impl 'static + Future<Output = anyhow::Result<T::Result>>
770 where
771 T::Result: 'static + Send,
772 {
773 let id = next_id.fetch_add(1, SeqCst);
774 let message = serde_json::to_string(&Request {
775 jsonrpc: JSON_RPC_VERSION,
776 id,
777 method: T::METHOD,
778 params,
779 })
780 .unwrap();
781
782 let (tx, rx) = oneshot::channel();
783 let handle_response = response_handlers
784 .lock()
785 .as_mut()
786 .ok_or_else(|| anyhow!("server shut down"))
787 .map(|handlers| {
788 let executor = executor.clone();
789 handlers.insert(
790 id,
791 Box::new(move |result| {
792 executor
793 .spawn(async move {
794 let response = match result {
795 Ok(response) => serde_json::from_str(&response)
796 .context("failed to deserialize response"),
797 Err(error) => Err(anyhow!("{}", error.message)),
798 };
799 _ = tx.send(response);
800 })
801 .detach();
802 }),
803 );
804 });
805
806 let send = outbound_tx
807 .try_send(message)
808 .context("failed to write to language server's stdin");
809
810 let mut timeout = executor.timer(LSP_REQUEST_TIMEOUT).fuse();
811 let started = Instant::now();
812 async move {
813 handle_response?;
814 send?;
815
816 let method = T::METHOD;
817 futures::select! {
818 response = rx.fuse() => {
819 let elapsed = started.elapsed();
820 log::trace!("Took {elapsed:?} to recieve response to {method:?} id {id}");
821 response?
822 }
823
824 _ = timeout => {
825 log::error!("Cancelled LSP request task for {method:?} id {id} which took over {LSP_REQUEST_TIMEOUT:?}");
826 anyhow::bail!("LSP request timeout");
827 }
828 }
829 }
830 }
831
832 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
833 Self::notify_internal::<T>(&self.outbound_tx, params)
834 }
835
836 fn notify_internal<T: notification::Notification>(
837 outbound_tx: &channel::Sender<String>,
838 params: T::Params,
839 ) -> Result<()> {
840 let message = serde_json::to_string(&Notification {
841 jsonrpc: JSON_RPC_VERSION,
842 method: T::METHOD,
843 params,
844 })
845 .unwrap();
846 outbound_tx.try_send(message)?;
847 Ok(())
848 }
849}
850
851impl Drop for LanguageServer {
852 fn drop(&mut self) {
853 if let Some(shutdown) = self.shutdown() {
854 self.executor.spawn(shutdown).detach();
855 }
856 }
857}
858
859impl Subscription {
860 pub fn detach(&mut self) {
861 match self {
862 Subscription::Notification {
863 notification_handlers,
864 ..
865 } => *notification_handlers = None,
866 Subscription::Io { io_handlers, .. } => *io_handlers = None,
867 }
868 }
869}
870
871impl fmt::Display for LanguageServerId {
872 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
873 self.0.fmt(f)
874 }
875}
876
877impl fmt::Debug for LanguageServer {
878 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
879 f.debug_struct("LanguageServer")
880 .field("id", &self.server_id.0)
881 .field("name", &self.name)
882 .finish_non_exhaustive()
883 }
884}
885
886impl Drop for Subscription {
887 fn drop(&mut self) {
888 match self {
889 Subscription::Notification {
890 method,
891 notification_handlers,
892 } => {
893 if let Some(handlers) = notification_handlers {
894 handlers.lock().remove(method);
895 }
896 }
897 Subscription::Io { id, io_handlers } => {
898 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
899 io_handlers.lock().remove(id);
900 }
901 }
902 }
903 }
904}
905
906#[cfg(any(test, feature = "test-support"))]
907#[derive(Clone)]
908pub struct FakeLanguageServer {
909 pub server: Arc<LanguageServer>,
910 notifications_rx: channel::Receiver<(String, String)>,
911}
912
913#[cfg(any(test, feature = "test-support"))]
914impl LanguageServer {
915 pub fn full_capabilities() -> ServerCapabilities {
916 ServerCapabilities {
917 document_highlight_provider: Some(OneOf::Left(true)),
918 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
919 document_formatting_provider: Some(OneOf::Left(true)),
920 document_range_formatting_provider: Some(OneOf::Left(true)),
921 definition_provider: Some(OneOf::Left(true)),
922 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
923 ..Default::default()
924 }
925 }
926
927 pub fn fake(
928 name: String,
929 capabilities: ServerCapabilities,
930 cx: AsyncAppContext,
931 ) -> (Self, FakeLanguageServer) {
932 let (stdin_writer, stdin_reader) = async_pipe::pipe();
933 let (stdout_writer, stdout_reader) = async_pipe::pipe();
934 let (notifications_tx, notifications_rx) = channel::unbounded();
935
936 let server = Self::new_internal(
937 LanguageServerId(0),
938 stdin_writer,
939 stdout_reader,
940 None::<async_pipe::PipeReader>,
941 None,
942 Path::new("/"),
943 None,
944 cx.clone(),
945 |_| {},
946 );
947 let fake = FakeLanguageServer {
948 server: Arc::new(Self::new_internal(
949 LanguageServerId(0),
950 stdout_writer,
951 stdin_reader,
952 None::<async_pipe::PipeReader>,
953 None,
954 Path::new("/"),
955 None,
956 cx,
957 move |msg| {
958 notifications_tx
959 .try_send((
960 msg.method.to_string(),
961 msg.params
962 .map(|raw_value| raw_value.get())
963 .unwrap_or("null")
964 .to_string(),
965 ))
966 .ok();
967 },
968 )),
969 notifications_rx,
970 };
971 fake.handle_request::<request::Initialize, _, _>({
972 let capabilities = capabilities;
973 move |_, _| {
974 let capabilities = capabilities.clone();
975 let name = name.clone();
976 async move {
977 Ok(InitializeResult {
978 capabilities,
979 server_info: Some(ServerInfo {
980 name,
981 ..Default::default()
982 }),
983 })
984 }
985 }
986 });
987
988 (server, fake)
989 }
990}
991
992#[cfg(any(test, feature = "test-support"))]
993impl FakeLanguageServer {
994 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
995 self.server.notify::<T>(params).ok();
996 }
997
998 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
999 where
1000 T: request::Request,
1001 T::Result: 'static + Send,
1002 {
1003 self.server.executor.start_waiting();
1004 self.server.request::<T>(params).await
1005 }
1006
1007 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
1008 self.server.executor.start_waiting();
1009 self.try_receive_notification::<T>().await.unwrap()
1010 }
1011
1012 pub async fn try_receive_notification<T: notification::Notification>(
1013 &mut self,
1014 ) -> Option<T::Params> {
1015 use futures::StreamExt as _;
1016
1017 loop {
1018 let (method, params) = self.notifications_rx.next().await?;
1019 if method == T::METHOD {
1020 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
1021 } else {
1022 log::info!("skipping message in fake language server {:?}", params);
1023 }
1024 }
1025 }
1026
1027 pub fn handle_request<T, F, Fut>(
1028 &self,
1029 mut handler: F,
1030 ) -> futures::channel::mpsc::UnboundedReceiver<()>
1031 where
1032 T: 'static + request::Request,
1033 T::Params: 'static + Send,
1034 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
1035 Fut: 'static + Send + Future<Output = Result<T::Result>>,
1036 {
1037 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
1038 self.server.remove_request_handler::<T>();
1039 self.server
1040 .on_request::<T, _, _>(move |params, cx| {
1041 let result = handler(params, cx.clone());
1042 let responded_tx = responded_tx.clone();
1043 async move {
1044 cx.background().simulate_random_delay().await;
1045 let result = result.await;
1046 responded_tx.unbounded_send(()).ok();
1047 result
1048 }
1049 })
1050 .detach();
1051 responded_rx
1052 }
1053
1054 pub fn handle_notification<T, F>(
1055 &self,
1056 mut handler: F,
1057 ) -> futures::channel::mpsc::UnboundedReceiver<()>
1058 where
1059 T: 'static + notification::Notification,
1060 T::Params: 'static + Send,
1061 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
1062 {
1063 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
1064 self.server.remove_notification_handler::<T>();
1065 self.server
1066 .on_notification::<T, _>(move |params, cx| {
1067 handler(params, cx.clone());
1068 handled_tx.unbounded_send(()).ok();
1069 })
1070 .detach();
1071 handled_rx
1072 }
1073
1074 pub fn remove_request_handler<T>(&mut self)
1075 where
1076 T: 'static + request::Request,
1077 {
1078 self.server.remove_request_handler::<T>();
1079 }
1080
1081 pub async fn start_progress(&self, token: impl Into<String>) {
1082 let token = token.into();
1083 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
1084 token: NumberOrString::String(token.clone()),
1085 })
1086 .await
1087 .unwrap();
1088 self.notify::<notification::Progress>(ProgressParams {
1089 token: NumberOrString::String(token),
1090 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
1091 });
1092 }
1093
1094 pub fn end_progress(&self, token: impl Into<String>) {
1095 self.notify::<notification::Progress>(ProgressParams {
1096 token: NumberOrString::String(token.into()),
1097 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1098 });
1099 }
1100}
1101
1102#[cfg(test)]
1103mod tests {
1104 use super::*;
1105 use gpui::TestAppContext;
1106
1107 #[ctor::ctor]
1108 fn init_logger() {
1109 if std::env::var("RUST_LOG").is_ok() {
1110 env_logger::init();
1111 }
1112 }
1113
1114 #[gpui::test]
1115 async fn test_fake(cx: &mut TestAppContext) {
1116 let (server, mut fake) =
1117 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
1118
1119 let (message_tx, message_rx) = channel::unbounded();
1120 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1121 server
1122 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1123 message_tx.try_send(params).unwrap()
1124 })
1125 .detach();
1126 server
1127 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1128 diagnostics_tx.try_send(params).unwrap()
1129 })
1130 .detach();
1131
1132 let server = server.initialize(None).await.unwrap();
1133 server
1134 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1135 text_document: TextDocumentItem::new(
1136 Url::from_str("file://a/b").unwrap(),
1137 "rust".to_string(),
1138 0,
1139 "".to_string(),
1140 ),
1141 })
1142 .unwrap();
1143 assert_eq!(
1144 fake.receive_notification::<notification::DidOpenTextDocument>()
1145 .await
1146 .text_document
1147 .uri
1148 .as_str(),
1149 "file://a/b"
1150 );
1151
1152 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1153 typ: MessageType::ERROR,
1154 message: "ok".to_string(),
1155 });
1156 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1157 uri: Url::from_str("file://b/c").unwrap(),
1158 version: Some(5),
1159 diagnostics: vec![],
1160 });
1161 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1162 assert_eq!(
1163 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1164 "file://b/c"
1165 );
1166
1167 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1168
1169 drop(server);
1170 fake.receive_notification::<notification::Exit>().await;
1171 }
1172}