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