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(Deserialize)]
107struct AnyNotification<'a> {
108 #[serde(default)]
109 id: Option<usize>,
110 #[serde(borrow)]
111 method: &'a str,
112 #[serde(borrow)]
113 params: &'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 &Value::from_str(notification.params.get()).unwrap()
161 )
162 .unwrap()
163 );
164 },
165 );
166
167 if let Some(name) = binary_path.file_name() {
168 server.name = name.to_string_lossy().to_string();
169 }
170 Ok(server)
171 }
172
173 fn new_internal<Stdin, Stdout, F>(
174 server_id: LanguageServerId,
175 stdin: Stdin,
176 stdout: Stdout,
177 server: Option<Child>,
178 root_path: &Path,
179 code_action_kinds: Option<Vec<CodeActionKind>>,
180 cx: AsyncAppContext,
181 on_unhandled_notification: F,
182 ) -> Self
183 where
184 Stdin: AsyncWrite + Unpin + Send + 'static,
185 Stdout: AsyncRead + Unpin + Send + 'static,
186 F: FnMut(AnyNotification) + 'static + Send,
187 {
188 let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
189 let (output_done_tx, output_done_rx) = barrier::channel();
190 let notification_handlers =
191 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
192 let response_handlers =
193 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
194 let io_handlers = Arc::new(Mutex::new(HashMap::default()));
195 let input_task = cx.spawn(|cx| {
196 Self::handle_input(
197 stdout,
198 on_unhandled_notification,
199 notification_handlers.clone(),
200 response_handlers.clone(),
201 io_handlers.clone(),
202 cx,
203 )
204 .log_err()
205 });
206 let output_task = cx.background().spawn({
207 Self::handle_output(
208 stdin,
209 outbound_rx,
210 output_done_tx,
211 response_handlers.clone(),
212 io_handlers.clone(),
213 )
214 .log_err()
215 });
216
217 Self {
218 server_id,
219 notification_handlers,
220 response_handlers,
221 io_handlers,
222 name: Default::default(),
223 capabilities: Default::default(),
224 code_action_kinds,
225 next_id: Default::default(),
226 outbound_tx,
227 executor: cx.background(),
228 io_tasks: Mutex::new(Some((input_task, output_task))),
229 output_done_rx: Mutex::new(Some(output_done_rx)),
230 root_path: root_path.to_path_buf(),
231 _server: server,
232 }
233 }
234
235 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
236 self.code_action_kinds.clone()
237 }
238
239 async fn handle_input<Stdout, F>(
240 stdout: Stdout,
241 mut on_unhandled_notification: F,
242 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
243 response_handlers: Arc<Mutex<Option<HashMap<usize, ResponseHandler>>>>,
244 io_handlers: Arc<Mutex<HashMap<usize, IoHandler>>>,
245 cx: AsyncAppContext,
246 ) -> anyhow::Result<()>
247 where
248 Stdout: AsyncRead + Unpin + Send + 'static,
249 F: FnMut(AnyNotification) + 'static + Send,
250 {
251 let mut stdout = BufReader::new(stdout);
252 let _clear_response_handlers = util::defer({
253 let response_handlers = response_handlers.clone();
254 move || {
255 response_handlers.lock().take();
256 }
257 });
258 let mut buffer = Vec::new();
259 loop {
260 buffer.clear();
261 stdout.read_until(b'\n', &mut buffer).await?;
262 stdout.read_until(b'\n', &mut buffer).await?;
263 let header = std::str::from_utf8(&buffer)?;
264 let message_len: usize = header
265 .strip_prefix(CONTENT_LEN_HEADER)
266 .ok_or_else(|| anyhow!("invalid LSP message header {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 LSP 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(DidChangeWatchedFilesClientCapabilities {
366 dynamic_registration: Some(true),
367 relative_pattern_support: Some(true),
368 }),
369 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
370 dynamic_registration: Some(true),
371 }),
372 workspace_folders: Some(true),
373 symbol: Some(WorkspaceSymbolClientCapabilities {
374 resolve_support: None,
375 ..WorkspaceSymbolClientCapabilities::default()
376 }),
377 ..Default::default()
378 }),
379 text_document: Some(TextDocumentClientCapabilities {
380 definition: Some(GotoCapability {
381 link_support: Some(true),
382 ..Default::default()
383 }),
384 code_action: Some(CodeActionClientCapabilities {
385 code_action_literal_support: Some(CodeActionLiteralSupport {
386 code_action_kind: CodeActionKindLiteralSupport {
387 value_set: vec![
388 CodeActionKind::REFACTOR.as_str().into(),
389 CodeActionKind::QUICKFIX.as_str().into(),
390 CodeActionKind::SOURCE.as_str().into(),
391 ],
392 },
393 }),
394 data_support: Some(true),
395 resolve_support: Some(CodeActionCapabilityResolveSupport {
396 properties: vec!["edit".to_string(), "command".to_string()],
397 }),
398 ..Default::default()
399 }),
400 completion: Some(CompletionClientCapabilities {
401 completion_item: Some(CompletionItemCapability {
402 snippet_support: Some(true),
403 resolve_support: Some(CompletionItemCapabilityResolveSupport {
404 properties: vec!["additionalTextEdits".to_string()],
405 }),
406 ..Default::default()
407 }),
408 ..Default::default()
409 }),
410 rename: Some(RenameClientCapabilities {
411 prepare_support: Some(true),
412 ..Default::default()
413 }),
414 hover: Some(HoverClientCapabilities {
415 content_format: Some(vec![MarkupKind::Markdown]),
416 ..Default::default()
417 }),
418 ..Default::default()
419 }),
420 experimental: Some(json!({
421 "serverStatusNotification": true,
422 })),
423 window: Some(WindowClientCapabilities {
424 work_done_progress: Some(true),
425 ..Default::default()
426 }),
427 ..Default::default()
428 },
429 trace: Default::default(),
430 workspace_folders: Some(vec![WorkspaceFolder {
431 uri: root_uri,
432 name: Default::default(),
433 }]),
434 client_info: Default::default(),
435 locale: Default::default(),
436 };
437
438 let response = self.request::<request::Initialize>(params).await?;
439 if let Some(info) = response.server_info {
440 self.name = info.name;
441 }
442 self.capabilities = response.capabilities;
443
444 self.notify::<notification::Initialized>(InitializedParams {})?;
445 Ok(Arc::new(self))
446 }
447
448 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
449 if let Some(tasks) = self.io_tasks.lock().take() {
450 let response_handlers = self.response_handlers.clone();
451 let next_id = AtomicUsize::new(self.next_id.load(SeqCst));
452 let outbound_tx = self.outbound_tx.clone();
453 let mut output_done = self.output_done_rx.lock().take().unwrap();
454 let shutdown_request = Self::request_internal::<request::Shutdown>(
455 &next_id,
456 &response_handlers,
457 &outbound_tx,
458 (),
459 );
460 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
461 outbound_tx.close();
462 Some(
463 async move {
464 log::debug!("language server shutdown started");
465 shutdown_request.await?;
466 response_handlers.lock().take();
467 exit?;
468 output_done.recv().await;
469 log::debug!("language server shutdown finished");
470 drop(tasks);
471 anyhow::Ok(())
472 }
473 .log_err(),
474 )
475 } else {
476 None
477 }
478 }
479
480 #[must_use]
481 pub fn on_notification<T, F>(&self, f: F) -> Subscription
482 where
483 T: notification::Notification,
484 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
485 {
486 self.on_custom_notification(T::METHOD, f)
487 }
488
489 #[must_use]
490 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
491 where
492 T: request::Request,
493 T::Params: 'static + Send,
494 F: 'static + Send + FnMut(T::Params, AsyncAppContext) -> Fut,
495 Fut: 'static + Future<Output = Result<T::Result>>,
496 {
497 self.on_custom_request(T::METHOD, f)
498 }
499
500 #[must_use]
501 pub fn on_io<F>(&self, f: F) -> Subscription
502 where
503 F: 'static + Send + FnMut(bool, &str),
504 {
505 let id = self.next_id.fetch_add(1, SeqCst);
506 self.io_handlers.lock().insert(id, Box::new(f));
507 Subscription::Io {
508 id,
509 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
510 }
511 }
512
513 pub fn remove_request_handler<T: request::Request>(&self) {
514 self.notification_handlers.lock().remove(T::METHOD);
515 }
516
517 pub fn remove_notification_handler<T: notification::Notification>(&self) {
518 self.notification_handlers.lock().remove(T::METHOD);
519 }
520
521 #[must_use]
522 pub fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
523 where
524 F: 'static + Send + FnMut(Params, AsyncAppContext),
525 Params: DeserializeOwned,
526 {
527 let prev_handler = self.notification_handlers.lock().insert(
528 method,
529 Box::new(move |_, params, cx| {
530 if let Some(params) = serde_json::from_str(params).log_err() {
531 f(params, cx);
532 }
533 }),
534 );
535 assert!(
536 prev_handler.is_none(),
537 "registered multiple handlers for the same LSP method"
538 );
539 Subscription::Notification {
540 method,
541 notification_handlers: Some(self.notification_handlers.clone()),
542 }
543 }
544
545 #[must_use]
546 pub fn on_custom_request<Params, Res, Fut, F>(
547 &self,
548 method: &'static str,
549 mut f: F,
550 ) -> Subscription
551 where
552 F: 'static + Send + FnMut(Params, AsyncAppContext) -> Fut,
553 Fut: 'static + Future<Output = Result<Res>>,
554 Params: DeserializeOwned + Send + 'static,
555 Res: Serialize,
556 {
557 let outbound_tx = self.outbound_tx.clone();
558 let prev_handler = self.notification_handlers.lock().insert(
559 method,
560 Box::new(move |id, params, cx| {
561 if let Some(id) = id {
562 match serde_json::from_str(params) {
563 Ok(params) => {
564 let response = f(params, cx.clone());
565 cx.foreground()
566 .spawn({
567 let outbound_tx = outbound_tx.clone();
568 async move {
569 let response = match response.await {
570 Ok(result) => Response {
571 jsonrpc: JSON_RPC_VERSION,
572 id,
573 result: Some(result),
574 error: None,
575 },
576 Err(error) => Response {
577 jsonrpc: JSON_RPC_VERSION,
578 id,
579 result: None,
580 error: Some(Error {
581 message: error.to_string(),
582 }),
583 },
584 };
585 if let Some(response) =
586 serde_json::to_string(&response).log_err()
587 {
588 outbound_tx.try_send(response).ok();
589 }
590 }
591 })
592 .detach();
593 }
594 Err(error) => {
595 log::error!(
596 "error deserializing {} request: {:?}, message: {:?}",
597 method,
598 error,
599 params
600 );
601 let response = AnyResponse {
602 jsonrpc: JSON_RPC_VERSION,
603 id,
604 result: None,
605 error: Some(Error {
606 message: error.to_string(),
607 }),
608 };
609 if let Some(response) = serde_json::to_string(&response).log_err() {
610 outbound_tx.try_send(response).ok();
611 }
612 }
613 }
614 }
615 }),
616 );
617 assert!(
618 prev_handler.is_none(),
619 "registered multiple handlers for the same LSP method"
620 );
621 Subscription::Notification {
622 method,
623 notification_handlers: Some(self.notification_handlers.clone()),
624 }
625 }
626
627 pub fn name<'a>(self: &'a Arc<Self>) -> &'a str {
628 &self.name
629 }
630
631 pub fn capabilities<'a>(self: &'a Arc<Self>) -> &'a ServerCapabilities {
632 &self.capabilities
633 }
634
635 pub fn server_id(&self) -> LanguageServerId {
636 self.server_id
637 }
638
639 pub fn root_path(&self) -> &PathBuf {
640 &self.root_path
641 }
642
643 pub fn request<T: request::Request>(
644 &self,
645 params: T::Params,
646 ) -> impl Future<Output = Result<T::Result>>
647 where
648 T::Result: 'static + Send,
649 {
650 Self::request_internal::<T>(
651 &self.next_id,
652 &self.response_handlers,
653 &self.outbound_tx,
654 params,
655 )
656 }
657
658 fn request_internal<T: request::Request>(
659 next_id: &AtomicUsize,
660 response_handlers: &Mutex<Option<HashMap<usize, ResponseHandler>>>,
661 outbound_tx: &channel::Sender<String>,
662 params: T::Params,
663 ) -> impl 'static + Future<Output = Result<T::Result>>
664 where
665 T::Result: 'static + Send,
666 {
667 let id = next_id.fetch_add(1, SeqCst);
668 let message = serde_json::to_string(&Request {
669 jsonrpc: JSON_RPC_VERSION,
670 id,
671 method: T::METHOD,
672 params,
673 })
674 .unwrap();
675
676 let (tx, rx) = oneshot::channel();
677 let handle_response = response_handlers
678 .lock()
679 .as_mut()
680 .ok_or_else(|| anyhow!("server shut down"))
681 .map(|handlers| {
682 handlers.insert(
683 id,
684 Box::new(move |result| {
685 let response = match result {
686 Ok(response) => serde_json::from_str(response)
687 .context("failed to deserialize response"),
688 Err(error) => Err(anyhow!("{}", error.message)),
689 };
690 let _ = tx.send(response);
691 }),
692 );
693 });
694
695 let send = outbound_tx
696 .try_send(message)
697 .context("failed to write to language server's stdin");
698
699 async move {
700 handle_response?;
701 send?;
702 rx.await?
703 }
704 }
705
706 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
707 Self::notify_internal::<T>(&self.outbound_tx, params)
708 }
709
710 fn notify_internal<T: notification::Notification>(
711 outbound_tx: &channel::Sender<String>,
712 params: T::Params,
713 ) -> Result<()> {
714 let message = serde_json::to_string(&Notification {
715 jsonrpc: JSON_RPC_VERSION,
716 method: T::METHOD,
717 params,
718 })
719 .unwrap();
720 outbound_tx.try_send(message)?;
721 Ok(())
722 }
723}
724
725impl Drop for LanguageServer {
726 fn drop(&mut self) {
727 if let Some(shutdown) = self.shutdown() {
728 self.executor.spawn(shutdown).detach();
729 }
730 }
731}
732
733impl Subscription {
734 pub fn detach(&mut self) {
735 match self {
736 Subscription::Notification {
737 notification_handlers,
738 ..
739 } => *notification_handlers = None,
740 Subscription::Io { io_handlers, .. } => *io_handlers = None,
741 }
742 }
743}
744
745impl fmt::Display for LanguageServerId {
746 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
747 self.0.fmt(f)
748 }
749}
750
751impl Drop for Subscription {
752 fn drop(&mut self) {
753 match self {
754 Subscription::Notification {
755 method,
756 notification_handlers,
757 } => {
758 if let Some(handlers) = notification_handlers {
759 handlers.lock().remove(method);
760 }
761 }
762 Subscription::Io { id, io_handlers } => {
763 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
764 io_handlers.lock().remove(id);
765 }
766 }
767 }
768 }
769}
770
771#[cfg(any(test, feature = "test-support"))]
772#[derive(Clone)]
773pub struct FakeLanguageServer {
774 pub server: Arc<LanguageServer>,
775 notifications_rx: channel::Receiver<(String, String)>,
776}
777
778#[cfg(any(test, feature = "test-support"))]
779impl LanguageServer {
780 pub fn full_capabilities() -> ServerCapabilities {
781 ServerCapabilities {
782 document_highlight_provider: Some(OneOf::Left(true)),
783 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
784 document_formatting_provider: Some(OneOf::Left(true)),
785 document_range_formatting_provider: Some(OneOf::Left(true)),
786 ..Default::default()
787 }
788 }
789
790 pub fn fake(
791 name: String,
792 capabilities: ServerCapabilities,
793 cx: AsyncAppContext,
794 ) -> (Self, FakeLanguageServer) {
795 let (stdin_writer, stdin_reader) = async_pipe::pipe();
796 let (stdout_writer, stdout_reader) = async_pipe::pipe();
797 let (notifications_tx, notifications_rx) = channel::unbounded();
798
799 let server = Self::new_internal(
800 LanguageServerId(0),
801 stdin_writer,
802 stdout_reader,
803 None,
804 Path::new("/"),
805 None,
806 cx.clone(),
807 |_| {},
808 );
809 let fake = FakeLanguageServer {
810 server: Arc::new(Self::new_internal(
811 LanguageServerId(0),
812 stdout_writer,
813 stdin_reader,
814 None,
815 Path::new("/"),
816 None,
817 cx,
818 move |msg| {
819 notifications_tx
820 .try_send((msg.method.to_string(), msg.params.get().to_string()))
821 .ok();
822 },
823 )),
824 notifications_rx,
825 };
826 fake.handle_request::<request::Initialize, _, _>({
827 let capabilities = capabilities;
828 move |_, _| {
829 let capabilities = capabilities.clone();
830 let name = name.clone();
831 async move {
832 Ok(InitializeResult {
833 capabilities,
834 server_info: Some(ServerInfo {
835 name,
836 ..Default::default()
837 }),
838 })
839 }
840 }
841 });
842
843 (server, fake)
844 }
845}
846
847#[cfg(any(test, feature = "test-support"))]
848impl FakeLanguageServer {
849 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
850 self.server.notify::<T>(params).ok();
851 }
852
853 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
854 where
855 T: request::Request,
856 T::Result: 'static + Send,
857 {
858 self.server.executor.start_waiting();
859 self.server.request::<T>(params).await
860 }
861
862 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
863 self.server.executor.start_waiting();
864 self.try_receive_notification::<T>().await.unwrap()
865 }
866
867 pub async fn try_receive_notification<T: notification::Notification>(
868 &mut self,
869 ) -> Option<T::Params> {
870 use futures::StreamExt as _;
871
872 loop {
873 let (method, params) = self.notifications_rx.next().await?;
874 if method == T::METHOD {
875 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
876 } else {
877 log::info!("skipping message in fake language server {:?}", params);
878 }
879 }
880 }
881
882 pub fn handle_request<T, F, Fut>(
883 &self,
884 mut handler: F,
885 ) -> futures::channel::mpsc::UnboundedReceiver<()>
886 where
887 T: 'static + request::Request,
888 T::Params: 'static + Send,
889 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
890 Fut: 'static + Send + Future<Output = Result<T::Result>>,
891 {
892 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
893 self.server.remove_request_handler::<T>();
894 self.server
895 .on_request::<T, _, _>(move |params, cx| {
896 let result = handler(params, cx.clone());
897 let responded_tx = responded_tx.clone();
898 async move {
899 cx.background().simulate_random_delay().await;
900 let result = result.await;
901 responded_tx.unbounded_send(()).ok();
902 result
903 }
904 })
905 .detach();
906 responded_rx
907 }
908
909 pub fn handle_notification<T, F>(
910 &self,
911 mut handler: F,
912 ) -> futures::channel::mpsc::UnboundedReceiver<()>
913 where
914 T: 'static + notification::Notification,
915 T::Params: 'static + Send,
916 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
917 {
918 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
919 self.server.remove_notification_handler::<T>();
920 self.server
921 .on_notification::<T, _>(move |params, cx| {
922 handler(params, cx.clone());
923 handled_tx.unbounded_send(()).ok();
924 })
925 .detach();
926 handled_rx
927 }
928
929 pub fn remove_request_handler<T>(&mut self)
930 where
931 T: 'static + request::Request,
932 {
933 self.server.remove_request_handler::<T>();
934 }
935
936 pub async fn start_progress(&self, token: impl Into<String>) {
937 let token = token.into();
938 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
939 token: NumberOrString::String(token.clone()),
940 })
941 .await
942 .unwrap();
943 self.notify::<notification::Progress>(ProgressParams {
944 token: NumberOrString::String(token),
945 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(Default::default())),
946 });
947 }
948
949 pub fn end_progress(&self, token: impl Into<String>) {
950 self.notify::<notification::Progress>(ProgressParams {
951 token: NumberOrString::String(token.into()),
952 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
953 });
954 }
955}
956
957#[cfg(test)]
958mod tests {
959 use super::*;
960 use gpui::TestAppContext;
961
962 #[ctor::ctor]
963 fn init_logger() {
964 if std::env::var("RUST_LOG").is_ok() {
965 env_logger::init();
966 }
967 }
968
969 #[gpui::test]
970 async fn test_fake(cx: &mut TestAppContext) {
971 let (server, mut fake) =
972 LanguageServer::fake("the-lsp".to_string(), Default::default(), cx.to_async());
973
974 let (message_tx, message_rx) = channel::unbounded();
975 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
976 server
977 .on_notification::<notification::ShowMessage, _>(move |params, _| {
978 message_tx.try_send(params).unwrap()
979 })
980 .detach();
981 server
982 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
983 diagnostics_tx.try_send(params).unwrap()
984 })
985 .detach();
986
987 let server = server.initialize(None).await.unwrap();
988 server
989 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
990 text_document: TextDocumentItem::new(
991 Url::from_str("file://a/b").unwrap(),
992 "rust".to_string(),
993 0,
994 "".to_string(),
995 ),
996 })
997 .unwrap();
998 assert_eq!(
999 fake.receive_notification::<notification::DidOpenTextDocument>()
1000 .await
1001 .text_document
1002 .uri
1003 .as_str(),
1004 "file://a/b"
1005 );
1006
1007 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1008 typ: MessageType::ERROR,
1009 message: "ok".to_string(),
1010 });
1011 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1012 uri: Url::from_str("file://b/c").unwrap(),
1013 version: Some(5),
1014 diagnostics: vec![],
1015 });
1016 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1017 assert_eq!(
1018 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1019 "file://b/c"
1020 );
1021
1022 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1023
1024 drop(server);
1025 fake.receive_notification::<notification::Exit>().await;
1026 }
1027}