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 fmt,
20 future::Future,
21 io::Write,
22 path::PathBuf,
23 str::{self, FromStr as _},
24 sync::{
25 atomic::{AtomicUsize, Ordering::SeqCst},
26 Arc, Weak,
27 },
28};
29use std::{path::Path, process::Stdio};
30use util::{ResultExt, TryFutureExt};
31
32const JSON_RPC_VERSION: &str = "2.0";
33const CONTENT_LEN_HEADER: &str = "Content-Length: ";
34
35type NotificationHandler = Box<dyn Send + FnMut(Option<usize>, &str, AsyncAppContext)>;
36type ResponseHandler = Box<dyn Send + FnOnce(Result<&str, Error>)>;
37type IoHandler = Box<dyn Send + FnMut(bool, &str)>;
38
39pub struct LanguageServer {
40 server_id: LanguageServerId,
41 next_id: AtomicUsize,
42 outbound_tx: channel::Sender<String>,
43 name: String,
44 capabilities: ServerCapabilities,
45 code_action_kinds: Option<Vec<CodeActionKind>>,
46 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
47 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
48 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
49 executor: Arc<executor::Background>,
50 #[allow(clippy::type_complexity)]
51 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
52 output_done_rx: Mutex<Option<barrier::Receiver>>,
53 root_path: PathBuf,
54 _server: Option<Child>,
55}
56
57#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
58#[repr(transparent)]
59pub struct LanguageServerId(pub usize);
60
61pub enum Subscription {
62 Notification {
63 method: &'static str,
64 notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
65 },
66 Io {
67 id: usize,
68 io_handlers: Option<Weak<Mutex<HashMap<usize, IoHandler>>>>,
69 },
70}
71
72#[derive(Serialize, Deserialize)]
73struct Request<'a, T> {
74 jsonrpc: &'static str,
75 id: usize,
76 method: &'a str,
77 params: T,
78}
79
80#[derive(Serialize, Deserialize)]
81struct AnyResponse<'a> {
82 jsonrpc: &'a str,
83 id: usize,
84 #[serde(default)]
85 error: Option<Error>,
86 #[serde(borrow)]
87 result: Option<&'a RawValue>,
88}
89
90#[derive(Serialize)]
91struct Response<T> {
92 jsonrpc: &'static str,
93 id: usize,
94 result: Option<T>,
95 error: Option<Error>,
96}
97
98#[derive(Serialize, Deserialize)]
99struct Notification<'a, T> {
100 jsonrpc: &'static str,
101 #[serde(borrow)]
102 method: &'a str,
103 params: T,
104}
105
106#[derive(Debug, Clone, Deserialize)]
107struct AnyNotification<'a> {
108 #[serde(default)]
109 id: Option<usize>,
110 #[serde(borrow)]
111 method: &'a str,
112 #[serde(borrow, default)]
113 params: Option<&'a RawValue>,
114}
115
116#[derive(Debug, Serialize, Deserialize)]
117struct Error {
118 message: String,
119}
120
121impl LanguageServer {
122 pub fn new<T: AsRef<std::ffi::OsStr>>(
123 server_id: LanguageServerId,
124 binary_path: &Path,
125 arguments: &[T],
126 root_path: &Path,
127 code_action_kinds: Option<Vec<CodeActionKind>>,
128 cx: AsyncAppContext,
129 ) -> Result<Self> {
130 let working_dir = if root_path.is_dir() {
131 root_path
132 } else {
133 root_path.parent().unwrap_or_else(|| Path::new("/"))
134 };
135
136 let mut server = process::Command::new(binary_path)
137 .current_dir(working_dir)
138 .args(arguments)
139 .stdin(Stdio::piped())
140 .stdout(Stdio::piped())
141 .stderr(Stdio::inherit())
142 .kill_on_drop(true)
143 .spawn()?;
144
145 let stdin = server.stdin.take().unwrap();
146 let stout = server.stdout.take().unwrap();
147 let mut server = Self::new_internal(
148 server_id,
149 stdin,
150 stout,
151 Some(server),
152 root_path,
153 code_action_kinds,
154 cx,
155 |notification| {
156 log::info!(
157 "unhandled notification {}:\n{}",
158 notification.method,
159 serde_json::to_string_pretty(
160 ¬ification
161 .params
162 .and_then(|params| Value::from_str(params.get()).ok())
163 .unwrap_or(Value::Null)
164 )
165 .unwrap(),
166 );
167 },
168 );
169
170 if let Some(name) = binary_path.file_name() {
171 server.name = name.to_string_lossy().to_string();
172 }
173 Ok(server)
174 }
175
176 fn new_internal<Stdin, Stdout, F>(
177 server_id: LanguageServerId,
178 stdin: Stdin,
179 stdout: Stdout,
180 server: Option<Child>,
181 root_path: &Path,
182 code_action_kinds: Option<Vec<CodeActionKind>>,
183 cx: AsyncAppContext,
184 on_unhandled_notification: F,
185 ) -> Self
186 where
187 Stdin: AsyncWrite + Unpin + Send + 'static,
188 Stdout: AsyncRead + Unpin + Send + 'static,
189 F: FnMut(AnyNotification) + 'static + Send,
190 {
191 let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
192 let (output_done_tx, output_done_rx) = barrier::channel();
193 let notification_handlers =
194 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
195 let response_handlers =
196 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
197 let io_handlers = Arc::new(Mutex::new(HashMap::default()));
198 let input_task = cx.spawn(|cx| {
199 Self::handle_input(
200 stdout,
201 on_unhandled_notification,
202 notification_handlers.clone(),
203 response_handlers.clone(),
204 io_handlers.clone(),
205 cx,
206 )
207 .log_err()
208 });
209 let output_task = cx.background().spawn({
210 Self::handle_output(
211 stdin,
212 outbound_rx,
213 output_done_tx,
214 response_handlers.clone(),
215 io_handlers.clone(),
216 )
217 .log_err()
218 });
219
220 Self {
221 server_id,
222 notification_handlers,
223 response_handlers,
224 io_handlers,
225 name: Default::default(),
226 capabilities: Default::default(),
227 code_action_kinds,
228 next_id: Default::default(),
229 outbound_tx,
230 executor: cx.background(),
231 io_tasks: Mutex::new(Some((input_task, output_task))),
232 output_done_rx: Mutex::new(Some(output_done_rx)),
233 root_path: root_path.to_path_buf(),
234 _server: server,
235 }
236 }
237
238 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
239 self.code_action_kinds.clone()
240 }
241
242 async fn handle_input<Stdout, F>(
243 stdout: Stdout,
244 mut on_unhandled_notification: F,
245 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
246 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
247 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
248 cx: AsyncAppContext,
249 ) -> anyhow::Result<()>
250 where
251 Stdout: AsyncRead + Unpin + Send + 'static,
252 F: FnMut(AnyNotification) + 'static + Send,
253 {
254 let mut stdout = BufReader::new(stdout);
255 let _clear_response_handlers = util::defer({
256 let response_handlers = response_handlers.clone();
257 move || {
258 response_handlers.lock().take();
259 }
260 });
261 let mut buffer = Vec::new();
262 loop {
263 buffer.clear();
264 stdout.read_until(b'\n', &mut buffer).await?;
265 stdout.read_until(b'\n', &mut buffer).await?;
266 let header = std::str::from_utf8(&buffer)?;
267 let message_len: usize = header
268 .strip_prefix(CONTENT_LEN_HEADER)
269 .ok_or_else(|| anyhow!("invalid LSP message header {header:?}"))?
270 .trim_end()
271 .parse()?;
272
273 buffer.resize(message_len, 0);
274 stdout.read_exact(&mut buffer).await?;
275
276 if let Ok(message) = str::from_utf8(&buffer) {
277 log::trace!("incoming message:{}", message);
278 for handler in io_handlers.lock().values_mut() {
279 handler(true, message);
280 }
281 }
282
283 if let Ok(msg) = serde_json::from_slice::<AnyNotification>(&buffer) {
284 if let Some(handler) = notification_handlers.lock().get_mut(msg.method) {
285 handler(
286 msg.id,
287 &msg.params.map(|params| params.get()).unwrap_or("null"),
288 cx.clone(),
289 );
290 } else {
291 on_unhandled_notification(msg);
292 }
293 } else if let Ok(AnyResponse {
294 id, error, result, ..
295 }) = serde_json::from_slice(&buffer)
296 {
297 if let Some(handler) = response_handlers
298 .lock()
299 .as_mut()
300 .and_then(|handlers| handlers.remove(&id))
301 {
302 if let Some(error) = error {
303 handler(Err(error));
304 } else if let Some(result) = result {
305 handler(Ok(result.get()));
306 } else {
307 handler(Ok("null"));
308 }
309 }
310 } else {
311 warn!(
312 "failed to deserialize LSP message:\n{}",
313 std::str::from_utf8(&buffer)?
314 );
315 }
316
317 // Don't starve the main thread when receiving lots of messages at once.
318 smol::future::yield_now().await;
319 }
320 }
321
322 async fn handle_output<Stdin>(
323 stdin: Stdin,
324 outbound_rx: channel::Receiver<String>,
325 output_done_tx: barrier::Sender,
326 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
327 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
328 ) -> anyhow::Result<()>
329 where
330 Stdin: AsyncWrite + Unpin + Send + 'static,
331 {
332 let mut stdin = BufWriter::new(stdin);
333 let _clear_response_handlers = util::defer({
334 let response_handlers = response_handlers.clone();
335 move || {
336 response_handlers.lock().take();
337 }
338 });
339 let mut content_len_buffer = Vec::new();
340 while let Ok(message) = outbound_rx.recv().await {
341 log::trace!("outgoing message:{}", message);
342 for handler in io_handlers.lock().values_mut() {
343 handler(false, &message);
344 }
345
346 content_len_buffer.clear();
347 write!(content_len_buffer, "{}", message.len()).unwrap();
348 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
349 stdin.write_all(&content_len_buffer).await?;
350 stdin.write_all("\r\n\r\n".as_bytes()).await?;
351 stdin.write_all(message.as_bytes()).await?;
352 stdin.flush().await?;
353 }
354 drop(output_done_tx);
355 Ok(())
356 }
357
358 /// Initializes a language server.
359 /// Note that `options` is used directly to construct [`InitializeParams`],
360 /// which is why it is owned.
361 pub async fn initialize(mut self, options: Option<Value>) -> Result<Arc<Self>> {
362 let root_uri = Url::from_file_path(&self.root_path).unwrap();
363 #[allow(deprecated)]
364 let params = InitializeParams {
365 process_id: Default::default(),
366 root_path: Default::default(),
367 root_uri: Some(root_uri.clone()),
368 initialization_options: options,
369 capabilities: ClientCapabilities {
370 workspace: Some(WorkspaceClientCapabilities {
371 configuration: Some(true),
372 did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
373 dynamic_registration: Some(true),
374 relative_pattern_support: Some(true),
375 }),
376 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
377 dynamic_registration: Some(true),
378 }),
379 workspace_folders: Some(true),
380 symbol: Some(WorkspaceSymbolClientCapabilities {
381 resolve_support: None,
382 ..WorkspaceSymbolClientCapabilities::default()
383 }),
384 ..Default::default()
385 }),
386 text_document: Some(TextDocumentClientCapabilities {
387 definition: Some(GotoCapability {
388 link_support: Some(true),
389 ..Default::default()
390 }),
391 code_action: Some(CodeActionClientCapabilities {
392 code_action_literal_support: Some(CodeActionLiteralSupport {
393 code_action_kind: CodeActionKindLiteralSupport {
394 value_set: vec![
395 CodeActionKind::REFACTOR.as_str().into(),
396 CodeActionKind::QUICKFIX.as_str().into(),
397 CodeActionKind::SOURCE.as_str().into(),
398 ],
399 },
400 }),
401 data_support: Some(true),
402 resolve_support: Some(CodeActionCapabilityResolveSupport {
403 properties: vec!["edit".to_string(), "command".to_string()],
404 }),
405 ..Default::default()
406 }),
407 completion: Some(CompletionClientCapabilities {
408 completion_item: Some(CompletionItemCapability {
409 snippet_support: Some(true),
410 resolve_support: Some(CompletionItemCapabilityResolveSupport {
411 properties: vec!["additionalTextEdits".to_string()],
412 }),
413 ..Default::default()
414 }),
415 ..Default::default()
416 }),
417 rename: Some(RenameClientCapabilities {
418 prepare_support: Some(true),
419 ..Default::default()
420 }),
421 hover: Some(HoverClientCapabilities {
422 content_format: Some(vec![MarkupKind::Markdown]),
423 ..Default::default()
424 }),
425 ..Default::default()
426 }),
427 experimental: Some(json!({
428 "serverStatusNotification": true,
429 })),
430 window: Some(WindowClientCapabilities {
431 work_done_progress: Some(true),
432 ..Default::default()
433 }),
434 ..Default::default()
435 },
436 trace: Default::default(),
437 workspace_folders: Some(vec![WorkspaceFolder {
438 uri: root_uri,
439 name: Default::default(),
440 }]),
441 client_info: Default::default(),
442 locale: Default::default(),
443 };
444
445 let response = self.request::<request::Initialize>(params).await?;
446 if let Some(info) = response.server_info {
447 self.name = info.name;
448 }
449 self.capabilities = response.capabilities;
450
451 self.notify::<notification::Initialized>(InitializedParams {})?;
452 Ok(Arc::new(self))
453 }
454
455 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
456 if let Some(tasks) = self.io_tasks.lock().take() {
457 let response_handlers = self.response_handlers.clone();
458 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
459 let outbound_tx = self.outbound_tx.clone();
460 let mut output_done = self.output_done_rx.lock().take().unwrap();
461 let shutdown_request = Self::request_internal::<request::Shutdown>(
462 &next_id,
463 &response_handlers,
464 &outbound_tx,
465 (),
466 );
467 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
468 outbound_tx.close();
469 Some(
470 async move {
471 log::debug!("language server shutdown started");
472 shutdown_request.await?;
473 response_handlers.lock().take();
474 exit?;
475 output_done.recv().await;
476 log::debug!("language server shutdown finished");
477 drop(tasks);
478 anyhow::Ok(())
479 }
480 .log_err(),
481 )
482 } else {
483 None
484 }
485 }
486
487 #[must_use]
488 pub fn on_notification<T, F>(&self, f: F) -> Subscription
489 where
490 T: notification::Notification,
491 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
492 {
493 self.on_custom_notification(T::METHOD, f)
494 }
495
496 #[must_use]
497 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
498 where
499 T: request::Request,
500 T::Params: 'static + Send,
501 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
502 Fut: 'static + Future<Output = Result<T::Result>>,
503 {
504 self.on_custom_request(T::METHOD, f)
505 }
506
507 #[must_use]
508 pub fn on_io<F>(&self, f: F) -> Subscription
509 where
510 F: 'static + Send + FnMut(bool, &str),
511 {
512 let id = self.next_id.fetch_add(1, SeqCst);
513 self.io_handlers.lock().insert(id, Box::new(f));
514 Subscription::Io {
515 id,
516 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
517 }
518 }
519
520 pub fn remove_request_handler<T: request::Request>(&self) {
521 self.notification_handlers.lock().remove(T::METHOD);
522 }
523
524 pub fn remove_notification_handler<T: notification::Notification>(&self) {
525 self.notification_handlers.lock().remove(T::METHOD);
526 }
527
528 #[must_use]
529 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
530 where
531 F: 'static + Send + FnMut(Params, AsyncAppContext),
532 Params: DeserializeOwned,
533 {
534 let prev_handler = self.notification_handlers.lock().insert(
535 method,
536 Box::new(move |_, params, cx| {
537 if let Some(params) = serde_json::from_str(params).log_err() {
538 f(params, cx);
539 }
540 }),
541 );
542 assert!(
543 prev_handler.is_none(),
544 "registered multiple handlers for the same LSP method"
545 );
546 Subscription::Notification {
547 method,
548 notification_handlers: Some(self.notification_handlers.clone()),
549 }
550 }
551
552 #[must_use]
553 pub fn on_custom_request<Params, Res, Fut, F>(
554 &self,
555 method: &'static str,
556 mut f: F,
557 ) -> Subscription
558 where
559 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
560 Fut: 'static + Future<Output = Result<Res>>,
561 Params: DeserializeOwned + Send + 'static,
562 Res: Serialize,
563 {
564 let outbound_tx = self.outbound_tx.clone();
565 let prev_handler = self.notification_handlers.lock().insert(
566 method,
567 Box::new(move |id, params, cx| {
568 if let Some(id) = id {
569 match serde_json::from_str(params) {
570 Ok(params) => {
571 let response = f(params, cx.clone());
572 cx.foreground()
573 .spawn({
574 let outbound_tx = outbound_tx.clone();
575 async move {
576 let response = match response.await {
577 Ok(result) => Response {
578 jsonrpc: JSON_RPC_VERSION,
579 id,
580 result: Some(result),
581 error: None,
582 },
583 Err(error) => Response {
584 jsonrpc: JSON_RPC_VERSION,
585 id,
586 result: None,
587 error: Some(Error {
588 message: error.to_string(),
589 }),
590 },
591 };
592 if let Some(response) =
593 serde_json::to_string(&response).log_err()
594 {
595 outbound_tx.try_send(response).ok();
596 }
597 }
598 })
599 .detach();
600 }
601 Err(error) => {
602 log::error!(
603 "error deserializing {} request: {:?}, message: {:?}",
604 method,
605 error,
606 params
607 );
608 let response = AnyResponse {
609 jsonrpc: JSON_RPC_VERSION,
610 id,
611 result: None,
612 error: Some(Error {
613 message: error.to_string(),
614 }),
615 };
616 if let Some(response) = serde_json::to_string(&response).log_err() {
617 outbound_tx.try_send(response).ok();
618 }
619 }
620 }
621 }
622 }),
623 );
624 assert!(
625 prev_handler.is_none(),
626 "registered multiple handlers for the same LSP method"
627 );
628 Subscription::Notification {
629 method,
630 notification_handlers: Some(self.notification_handlers.clone()),
631 }
632 }
633
634 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
635 &self.name
636 }
637
638 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
639 &self.capabilities
640 }
641
642 pub fn server_id(&self) -> LanguageServerId {
643 self.server_id
644 }
645
646 pub fn root_path(&self) -> &PathBuf {
647 &self.root_path
648 }
649
650 pub fn request<T: request::Request>(
651 &self,
652 params: T::Params,
653 ) -> impl Future<Output = Result<T::Result>>
654 where
655 T::Result: 'static + Send,
656 {
657 Self::request_internal::<T>(
658 &self.next_id,
659 &self.response_handlers,
660 &self.outbound_tx,
661 params,
662 )
663 }
664
665 fn request_internal<T: request::Request>(
666 next_id: &AtomicUsize,
667 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
668 outbound_tx: &channel::Sender<String>,
669 params: T::Params,
670 ) -> impl 'static + Future<Output = Result<T::Result>>
671 where
672 T::Result: 'static + Send,
673 {
674 let id = next_id.fetch_add(1, SeqCst);
675 let message = serde_json::to_string(&Request {
676 jsonrpc: JSON_RPC_VERSION,
677 id,
678 method: T::METHOD,
679 params,
680 })
681 .unwrap();
682
683 let (tx, rx) = oneshot::channel();
684 let handle_response = response_handlers
685 .lock()
686 .as_mut()
687 .ok_or_else(|| anyhow!("server shut down"))
688 .map(|handlers| {
689 handlers.insert(
690 id,
691 Box::new(move |result| {
692 let response = match result {
693 Ok(response) => serde_json::from_str(response)
694 .context("failed to deserialize response"),
695 Err(error) => Err(anyhow!("{}", error.message)),
696 };
697 let _ = tx.send(response);
698 }),
699 );
700 });
701
702 let send = outbound_tx
703 .try_send(message)
704 .context("failed to write to language server's stdin");
705
706 async move {
707 handle_response?;
708 send?;
709 rx.await?
710 }
711 }
712
713 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
714 Self::notify_internal::<T>(&self.outbound_tx, params)
715 }
716
717 fn notify_internal<T: notification::Notification>(
718 outbound_tx: &channel::Sender<String>,
719 params: T::Params,
720 ) -> Result<()> {
721 let message = serde_json::to_string(&Notification {
722 jsonrpc: JSON_RPC_VERSION,
723 method: T::METHOD,
724 params,
725 })
726 .unwrap();
727 outbound_tx.try_send(message)?;
728 Ok(())
729 }
730}
731
732impl Drop for LanguageServer {
733 fn drop(&mut self) {
734 if let Some(shutdown) = self.shutdown() {
735 self.executor.spawn(shutdown).detach();
736 }
737 }
738}
739
740impl Subscription {
741 pub fn detach(&mut self) {
742 match self {
743 Subscription::Notification {
744 notification_handlers,
745 ..
746 } => *notification_handlers = None,
747 Subscription::Io { io_handlers, .. } => *io_handlers = None,
748 }
749 }
750}
751
752impl fmt::Display for LanguageServerId {
753 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
754 self.0.fmt(f)
755 }
756}
757
758impl fmt::Debug for LanguageServer {
759 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
760 f.debug_struct("LanguageServer")
761 .field("id", &self.server_id.0)
762 .field("name", &self.name)
763 .finish_non_exhaustive()
764 }
765}
766
767impl Drop for Subscription {
768 fn drop(&mut self) {
769 match self {
770 Subscription::Notification {
771 method,
772 notification_handlers,
773 } => {
774 if let Some(handlers) = notification_handlers {
775 handlers.lock().remove(method);
776 }
777 }
778 Subscription::Io { id, io_handlers } => {
779 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
780 io_handlers.lock().remove(id);
781 }
782 }
783 }
784 }
785}
786
787#[cfg(any(test, feature = "test-support"))]
788#[derive(Clone)]
789pub struct FakeLanguageServer {
790 pub server: Arc<LanguageServer>,
791 notifications_rx: channel::Receiver<(String, String)>,
792}
793
794#[cfg(any(test, feature = "test-support"))]
795impl LanguageServer {
796 pub fn full_capabilities() -> ServerCapabilities {
797 ServerCapabilities {
798 document_highlight_provider: Some(OneOf::Left(true)),
799 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
800 document_formatting_provider: Some(OneOf::Left(true)),
801 document_range_formatting_provider: Some(OneOf::Left(true)),
802 definition_provider: Some(OneOf::Left(true)),
803 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
804 ..Default::default()
805 }
806 }
807
808 pub fn fake(
809 name: String,
810 capabilities: ServerCapabilities,
811 cx: AsyncAppContext,
812 ) -> (Self, FakeLanguageServer) {
813 let (stdin_writer, stdin_reader) = async_pipe::pipe();
814 let (stdout_writer, stdout_reader) = async_pipe::pipe();
815 let (notifications_tx, notifications_rx) = channel::unbounded();
816
817 let server = Self::new_internal(
818 LanguageServerId(0),
819 stdin_writer,
820 stdout_reader,
821 None,
822 Path::new("/"),
823 None,
824 cx.clone(),
825 |_| {},
826 );
827 let fake = FakeLanguageServer {
828 server: Arc::new(Self::new_internal(
829 LanguageServerId(0),
830 stdout_writer,
831 stdin_reader,
832 None,
833 Path::new("/"),
834 None,
835 cx,
836 move |msg| {
837 notifications_tx
838 .try_send((
839 msg.method.to_string(),
840 msg.params
841 .map(|raw_value| raw_value.get())
842 .unwrap_or("null")
843 .to_string(),
844 ))
845 .ok();
846 },
847 )),
848 notifications_rx,
849 };
850 fake.handle_request::<request::Initialize, _, _>({
851 let capabilities = capabilities;
852 move |_, _| {
853 let capabilities = capabilities.clone();
854 let name = name.clone();
855 async move {
856 Ok(InitializeResult {
857 capabilities,
858 server_info: Some(ServerInfo {
859 name,
860 ..Default::default()
861 }),
862 })
863 }
864 }
865 });
866
867 (server, fake)
868 }
869}
870
871#[cfg(any(test, feature = "test-support"))]
872impl FakeLanguageServer {
873 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
874 self.server.notify::<T>(params).ok();
875 }
876
877 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
878 where
879 T: request::Request,
880 T::Result: 'static + Send,
881 {
882 self.server.executor.start_waiting();
883 self.server.request::<T>(params).await
884 }
885
886 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
887 self.server.executor.start_waiting();
888 self.try_receive_notification::<T>().await.unwrap()
889 }
890
891 pub async fn try_receive_notification<T: notification::Notification>(
892 &mut self,
893 ) -> Option<T::Params> {
894 use futures::StreamExt as _;
895
896 loop {
897 let (method, params) = self.notifications_rx.next().await?;
898 if method == T::METHOD {
899 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
900 } else {
901 log::info!("skipping message in fake language server {:?}", params);
902 }
903 }
904 }
905
906 pub fn handle_request<T, F, Fut>(
907 &self,
908 mut handler: F,
909 ) -> futures::channel::mpsc::UnboundedReceiver<()>
910 where
911 T: 'static + request::Request,
912 T::Params: 'static + Send,
913 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
914 Fut: 'static + Send + Future<Output = Result<T::Result>>,
915 {
916 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
917 self.server.remove_request_handler::<T>();
918 self.server
919 .on_request::<T, _, _>(move |params, cx| {
920 let result = handler(params, cx.clone());
921 let responded_tx = responded_tx.clone();
922 async move {
923 cx.background().simulate_random_delay().await;
924 let result = result.await;
925 responded_tx.unbounded_send(()).ok();
926 result
927 }
928 })
929 .detach();
930 responded_rx
931 }
932
933 pub fn handle_notification<T, F>(
934 &self,
935 mut handler: F,
936 ) -> futures::channel::mpsc::UnboundedReceiver<()>
937 where
938 T: 'static + notification::Notification,
939 T::Params: 'static + Send,
940 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
941 {
942 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
943 self.server.remove_notification_handler::<T>();
944 self.server
945 .on_notification::<T, _>(move |params, cx| {
946 handler(params, cx.clone());
947 handled_tx.unbounded_send(()).ok();
948 })
949 .detach();
950 handled_rx
951 }
952
953 pub fn remove_request_handler<T>(&mut self)
954 where
955 T: 'static + request::Request,
956 {
957 self.server.remove_request_handler::<T>();
958 }
959
960 pub async fn start_progress(&self, token: impl Into<String>) {
961 let token = token.into();
962 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
963 token: NumberOrString::String(token.clone()),
964 })
965 .await
966 .unwrap();
967 self.notify::<notification::Progress>(ProgressParams {
968 token: NumberOrString::String(token),
969 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
970 });
971 }
972
973 pub fn end_progress(&self, token: impl Into<String>) {
974 self.notify::<notification::Progress>(ProgressParams {
975 token: NumberOrString::String(token.into()),
976 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
977 });
978 }
979}
980
981#[cfg(test)]
982mod tests {
983 use super::*;
984 use gpui::TestAppContext;
985
986 #[ctor::ctor]
987 fn init_logger() {
988 if std::env::var("RUST_LOG").is_ok() {
989 env_logger::init();
990 }
991 }
992
993 #[gpui::test]
994 async fn test_fake(cx: &mut TestAppContext) {
995 let (server, mut fake) =
996 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
997
998 let (message_tx, message_rx) = channel::unbounded();
999 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1000 server
1001 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1002 message_tx.try_send(params).unwrap()
1003 })
1004 .detach();
1005 server
1006 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1007 diagnostics_tx.try_send(params).unwrap()
1008 })
1009 .detach();
1010
1011 let server = server.initialize(None).await.unwrap();
1012 server
1013 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1014 text_document: TextDocumentItem::new(
1015 Url::from_str("file://a/b").unwrap(),
1016 "rust".to_string(),
1017 0,
1018 "".to_string(),
1019 ),
1020 })
1021 .unwrap();
1022 assert_eq!(
1023 fake.receive_notification::<notification::DidOpenTextDocument>()
1024 .await
1025 .text_document
1026 .uri
1027 .as_str(),
1028 "file://a/b"
1029 );
1030
1031 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1032 typ: MessageType::ERROR,
1033 message: "ok".to_string(),
1034 });
1035 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1036 uri: Url::from_str("file://b/c").unwrap(),
1037 version: Some(5),
1038 diagnostics: vec![],
1039 });
1040 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1041 assert_eq!(
1042 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1043 "file://b/c"
1044 );
1045
1046 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1047
1048 drop(server);
1049 fake.receive_notification::<notification::Exit>().await;
1050 }
1051}