1mod input_handler;
2
3pub use lsp_types::request::*;
4pub use lsp_types::*;
5
6use anyhow::{anyhow, Context, Result};
7use collections::HashMap;
8use futures::{channel::oneshot, io::BufWriter, select, AsyncRead, AsyncWrite, Future, FutureExt};
9use gpui::{AppContext, AsyncAppContext, BackgroundExecutor, Task};
10use parking_lot::Mutex;
11use postage::{barrier, prelude::Stream};
12use serde::{de::DeserializeOwned, Deserialize, Serialize};
13use serde_json::{json, value::RawValue, Value};
14use smol::{
15 channel,
16 io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
17 process::{self, Child},
18};
19
20#[cfg(target_os = "windows")]
21use smol::process::windows::CommandExt;
22
23use std::{
24 ffi::OsString,
25 fmt,
26 io::Write,
27 path::PathBuf,
28 pin::Pin,
29 sync::{
30 atomic::{AtomicI32, Ordering::SeqCst},
31 Arc, Weak,
32 },
33 task::Poll,
34 time::{Duration, Instant},
35};
36use std::{path::Path, process::Stdio};
37use util::{ResultExt, TryFutureExt};
38
39const JSON_RPC_VERSION: &str = "2.0";
40const CONTENT_LEN_HEADER: &str = "Content-Length: ";
41
42const LSP_REQUEST_TIMEOUT: Duration = Duration::from_secs(60 * 2);
43const SERVER_SHUTDOWN_TIMEOUT: Duration = Duration::from_secs(5);
44
45type NotificationHandler = Box<dyn Send + FnMut(Option<RequestId>, Value, AsyncAppContext)>;
46type ResponseHandler = Box<dyn Send + FnOnce(Result<String, Error>)>;
47type IoHandler = Box<dyn Send + FnMut(IoKind, &str)>;
48
49/// Kind of language server stdio given to an IO handler.
50#[derive(Debug, Clone, Copy)]
51pub enum IoKind {
52 StdOut,
53 StdIn,
54 StdErr,
55}
56
57/// Represents a launchable language server. This can either be a standalone binary or the path
58/// to a runtime with arguments to instruct it to launch the actual language server file.
59#[derive(Debug, Clone, Deserialize)]
60pub struct LanguageServerBinary {
61 pub path: PathBuf,
62 pub arguments: Vec<OsString>,
63 pub env: Option<HashMap<String, String>>,
64}
65
66/// A running language server process.
67pub struct LanguageServer {
68 server_id: LanguageServerId,
69 next_id: AtomicI32,
70 outbound_tx: channel::Sender<String>,
71 name: Arc<str>,
72 capabilities: ServerCapabilities,
73 code_action_kinds: Option<Vec<CodeActionKind>>,
74 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
75 response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
76 io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
77 executor: BackgroundExecutor,
78 #[allow(clippy::type_complexity)]
79 io_tasks: Mutex<Option<(Task<Option<()>>, Task<Option<()>>)>>,
80 output_done_rx: Mutex<Option<barrier::Receiver>>,
81 root_path: PathBuf,
82 working_dir: PathBuf,
83 server: Arc<Mutex<Option<Child>>>,
84}
85
86/// Identifies a running language server.
87#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
88#[repr(transparent)]
89pub struct LanguageServerId(pub usize);
90
91/// Handle to a language server RPC activity subscription.
92pub enum Subscription {
93 Notification {
94 method: &'static str,
95 notification_handlers: Option<Arc<Mutex<HashMap<&'static str, NotificationHandler>>>>,
96 },
97 Io {
98 id: i32,
99 io_handlers: Option<Weak<Mutex<HashMap<i32, IoHandler>>>>,
100 },
101}
102
103/// Language server protocol RPC request message ID.
104///
105/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
106#[derive(Debug, Clone, Eq, PartialEq, Hash, Serialize, Deserialize)]
107#[serde(untagged)]
108pub enum RequestId {
109 Int(i32),
110 Str(String),
111}
112
113/// Language server protocol RPC request message.
114///
115/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
116#[derive(Serialize, Deserialize)]
117pub struct Request<'a, T> {
118 jsonrpc: &'static str,
119 id: RequestId,
120 method: &'a str,
121 params: T,
122}
123
124/// Language server protocol RPC request response message before it is deserialized into a concrete type.
125#[derive(Serialize, Deserialize)]
126struct AnyResponse<'a> {
127 jsonrpc: &'a str,
128 id: RequestId,
129 #[serde(default)]
130 error: Option<Error>,
131 #[serde(borrow)]
132 result: Option<&'a RawValue>,
133}
134
135/// Language server protocol RPC request response message.
136///
137/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#responseMessage)
138#[derive(Serialize)]
139struct Response<T> {
140 jsonrpc: &'static str,
141 id: RequestId,
142 #[serde(flatten)]
143 value: LspResult<T>,
144}
145
146#[derive(Serialize)]
147#[serde(rename_all = "snake_case")]
148enum LspResult<T> {
149 #[serde(rename = "result")]
150 Ok(Option<T>),
151 Error(Option<Error>),
152}
153
154/// Language server protocol RPC notification message.
155///
156/// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
157#[derive(Serialize, Deserialize)]
158struct Notification<'a, T> {
159 jsonrpc: &'static str,
160 #[serde(borrow)]
161 method: &'a str,
162 params: T,
163}
164
165/// Language server RPC notification message before it is deserialized into a concrete type.
166#[derive(Debug, Clone, Deserialize)]
167struct AnyNotification {
168 #[serde(default)]
169 id: Option<RequestId>,
170 method: String,
171 #[serde(default)]
172 params: Option<Value>,
173}
174
175#[derive(Debug, Serialize, Deserialize)]
176struct Error {
177 message: String,
178}
179
180pub trait LspRequestFuture<O>: Future<Output = O> {
181 fn id(&self) -> i32;
182}
183
184struct LspRequest<F> {
185 id: i32,
186 request: F,
187}
188
189impl<F> LspRequest<F> {
190 pub fn new(id: i32, request: F) -> Self {
191 Self { id, request }
192 }
193}
194
195impl<F: Future> Future for LspRequest<F> {
196 type Output = F::Output;
197
198 fn poll(self: Pin<&mut Self>, cx: &mut std::task::Context<'_>) -> Poll<Self::Output> {
199 // SAFETY: This is standard pin projection, we're pinned so our fields must be pinned.
200 let inner = unsafe { Pin::new_unchecked(&mut self.get_unchecked_mut().request) };
201 inner.poll(cx)
202 }
203}
204
205impl<F: Future> LspRequestFuture<F::Output> for LspRequest<F> {
206 fn id(&self) -> i32 {
207 self.id
208 }
209}
210
211/// Experimental: Informs the end user about the state of the server
212///
213/// [Rust Analyzer Specification](https://github.com/rust-lang/rust-analyzer/blob/master/docs/dev/lsp-extensions.md#server-status)
214#[derive(Debug)]
215pub enum ServerStatus {}
216
217/// Other(String) variant to handle unknown values due to this still being experimental
218#[derive(Debug, PartialEq, Deserialize, Serialize, Clone)]
219#[serde(rename_all = "camelCase")]
220pub enum ServerHealthStatus {
221 Ok,
222 Warning,
223 Error,
224 Other(String),
225}
226
227#[derive(Debug, PartialEq, Deserialize, Serialize, Clone)]
228#[serde(rename_all = "camelCase")]
229pub struct ServerStatusParams {
230 pub health: ServerHealthStatus,
231 pub message: Option<String>,
232}
233
234impl lsp_types::notification::Notification for ServerStatus {
235 type Params = ServerStatusParams;
236 const METHOD: &'static str = "experimental/serverStatus";
237}
238
239impl LanguageServer {
240 /// Starts a language server process.
241 pub fn new(
242 stderr_capture: Arc<Mutex<Option<String>>>,
243 server_id: LanguageServerId,
244 binary: LanguageServerBinary,
245 root_path: &Path,
246 code_action_kinds: Option<Vec<CodeActionKind>>,
247 cx: AsyncAppContext,
248 ) -> Result<Self> {
249 let working_dir = if root_path.is_dir() {
250 root_path
251 } else {
252 root_path.parent().unwrap_or_else(|| Path::new("/"))
253 };
254
255 log::info!(
256 "starting language server. binary path: {:?}, working directory: {:?}, args: {:?}",
257 binary.path,
258 working_dir,
259 &binary.arguments
260 );
261
262 let mut command = process::Command::new(&binary.path);
263 command
264 .current_dir(working_dir)
265 .args(&binary.arguments)
266 .envs(binary.env.unwrap_or_default())
267 .stdin(Stdio::piped())
268 .stdout(Stdio::piped())
269 .stderr(Stdio::piped())
270 .kill_on_drop(true);
271 #[cfg(windows)]
272 command.creation_flags(windows::Win32::System::Threading::CREATE_NO_WINDOW.0);
273 let mut server = command.spawn().with_context(|| {
274 format!(
275 "failed to spawn command. path: {:?}, working directory: {:?}, args: {:?}",
276 binary.path, working_dir, &binary.arguments
277 )
278 })?;
279
280 let stdin = server.stdin.take().unwrap();
281 let stdout = server.stdout.take().unwrap();
282 let stderr = server.stderr.take().unwrap();
283 let mut server = Self::new_internal(
284 server_id,
285 stdin,
286 stdout,
287 Some(stderr),
288 stderr_capture,
289 Some(server),
290 root_path,
291 working_dir,
292 code_action_kinds,
293 cx,
294 move |notification| {
295 log::info!(
296 "Language server with id {} sent unhandled notification {}:\n{}",
297 server_id,
298 notification.method,
299 serde_json::to_string_pretty(¬ification.params).unwrap(),
300 );
301 },
302 );
303
304 if let Some(name) = binary.path.file_name() {
305 server.name = name.to_string_lossy().into();
306 }
307
308 Ok(server)
309 }
310
311 #[allow(clippy::too_many_arguments)]
312 fn new_internal<Stdin, Stdout, Stderr, F>(
313 server_id: LanguageServerId,
314 stdin: Stdin,
315 stdout: Stdout,
316 stderr: Option<Stderr>,
317 stderr_capture: Arc<Mutex<Option<String>>>,
318 server: Option<Child>,
319 root_path: &Path,
320 working_dir: &Path,
321 code_action_kinds: Option<Vec<CodeActionKind>>,
322 cx: AsyncAppContext,
323 on_unhandled_notification: F,
324 ) -> Self
325 where
326 Stdin: AsyncWrite + Unpin + Send + 'static,
327 Stdout: AsyncRead + Unpin + Send + 'static,
328 Stderr: AsyncRead + Unpin + Send + 'static,
329 F: FnMut(AnyNotification) + 'static + Send + Sync + Clone,
330 {
331 let (outbound_tx, outbound_rx) = channel::unbounded::<String>();
332 let (output_done_tx, output_done_rx) = barrier::channel();
333 let notification_handlers =
334 Arc::new(Mutex::new(HashMap::<_, NotificationHandler>::default()));
335 let response_handlers =
336 Arc::new(Mutex::new(Some(HashMap::<_, ResponseHandler>::default())));
337 let io_handlers = Arc::new(Mutex::new(HashMap::default()));
338
339 let stdout_input_task = cx.spawn({
340 let on_unhandled_notification = on_unhandled_notification.clone();
341 let notification_handlers = notification_handlers.clone();
342 let response_handlers = response_handlers.clone();
343 let io_handlers = io_handlers.clone();
344 move |cx| {
345 Self::handle_input(
346 stdout,
347 on_unhandled_notification,
348 notification_handlers,
349 response_handlers,
350 io_handlers,
351 cx,
352 )
353 .log_err()
354 }
355 });
356 let stderr_input_task = stderr
357 .map(|stderr| {
358 let io_handlers = io_handlers.clone();
359 let stderr_captures = stderr_capture.clone();
360 cx.spawn(|_| Self::handle_stderr(stderr, io_handlers, stderr_captures).log_err())
361 })
362 .unwrap_or_else(|| Task::Ready(Some(None)));
363 let input_task = cx.spawn(|_| async move {
364 let (stdout, stderr) = futures::join!(stdout_input_task, stderr_input_task);
365 stdout.or(stderr)
366 });
367 let output_task = cx.background_executor().spawn({
368 Self::handle_output(
369 stdin,
370 outbound_rx,
371 output_done_tx,
372 response_handlers.clone(),
373 io_handlers.clone(),
374 )
375 .log_err()
376 });
377
378 Self {
379 server_id,
380 notification_handlers,
381 response_handlers,
382 io_handlers,
383 name: "".into(),
384 capabilities: Default::default(),
385 code_action_kinds,
386 next_id: Default::default(),
387 outbound_tx,
388 executor: cx.background_executor().clone(),
389 io_tasks: Mutex::new(Some((input_task, output_task))),
390 output_done_rx: Mutex::new(Some(output_done_rx)),
391 root_path: root_path.to_path_buf(),
392 working_dir: working_dir.to_path_buf(),
393 server: Arc::new(Mutex::new(server)),
394 }
395 }
396
397 /// List of code action kinds this language server reports being able to emit.
398 pub fn code_action_kinds(&self) -> Option<Vec<CodeActionKind>> {
399 self.code_action_kinds.clone()
400 }
401
402 async fn handle_input<Stdout, F>(
403 stdout: Stdout,
404 mut on_unhandled_notification: F,
405 notification_handlers: Arc<Mutex<HashMap<&'static str, NotificationHandler>>>,
406 response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
407 io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
408 cx: AsyncAppContext,
409 ) -> anyhow::Result<()>
410 where
411 Stdout: AsyncRead + Unpin + Send + 'static,
412 F: FnMut(AnyNotification) + 'static + Send,
413 {
414 use smol::stream::StreamExt;
415 let stdout = BufReader::new(stdout);
416 let _clear_response_handlers = util::defer({
417 let response_handlers = response_handlers.clone();
418 move || {
419 response_handlers.lock().take();
420 }
421 });
422 let mut input_handler = input_handler::LspStdoutHandler::new(
423 stdout,
424 response_handlers,
425 io_handlers,
426 cx.background_executor().clone(),
427 );
428
429 while let Some(msg) = input_handler.notifications_channel.next().await {
430 {
431 let mut notification_handlers = notification_handlers.lock();
432 if let Some(handler) = notification_handlers.get_mut(msg.method.as_str()) {
433 handler(msg.id, msg.params.unwrap_or(Value::Null), cx.clone());
434 } else {
435 drop(notification_handlers);
436 on_unhandled_notification(msg);
437 }
438 }
439
440 // Don't starve the main thread when receiving lots of notifications at once.
441 smol::future::yield_now().await;
442 }
443 input_handler.loop_handle.await
444 }
445
446 async fn handle_stderr<Stderr>(
447 stderr: Stderr,
448 io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
449 stderr_capture: Arc<Mutex<Option<String>>>,
450 ) -> anyhow::Result<()>
451 where
452 Stderr: AsyncRead + Unpin + Send + 'static,
453 {
454 let mut stderr = BufReader::new(stderr);
455 let mut buffer = Vec::new();
456
457 loop {
458 buffer.clear();
459
460 let bytes_read = stderr.read_until(b'\n', &mut buffer).await?;
461 if bytes_read == 0 {
462 return Ok(());
463 }
464
465 if let Ok(message) = std::str::from_utf8(&buffer) {
466 log::trace!("incoming stderr message:{message}");
467 for handler in io_handlers.lock().values_mut() {
468 handler(IoKind::StdErr, message);
469 }
470
471 if let Some(stderr) = stderr_capture.lock().as_mut() {
472 stderr.push_str(message);
473 }
474 }
475
476 // Don't starve the main thread when receiving lots of messages at once.
477 smol::future::yield_now().await;
478 }
479 }
480
481 async fn handle_output<Stdin>(
482 stdin: Stdin,
483 outbound_rx: channel::Receiver<String>,
484 output_done_tx: barrier::Sender,
485 response_handlers: Arc<Mutex<Option<HashMap<RequestId, ResponseHandler>>>>,
486 io_handlers: Arc<Mutex<HashMap<i32, IoHandler>>>,
487 ) -> anyhow::Result<()>
488 where
489 Stdin: AsyncWrite + Unpin + Send + 'static,
490 {
491 let mut stdin = BufWriter::new(stdin);
492 let _clear_response_handlers = util::defer({
493 let response_handlers = response_handlers.clone();
494 move || {
495 response_handlers.lock().take();
496 }
497 });
498 let mut content_len_buffer = Vec::new();
499 while let Ok(message) = outbound_rx.recv().await {
500 log::trace!("outgoing message:{}", message);
501 for handler in io_handlers.lock().values_mut() {
502 handler(IoKind::StdIn, &message);
503 }
504
505 content_len_buffer.clear();
506 write!(content_len_buffer, "{}", message.len()).unwrap();
507 stdin.write_all(CONTENT_LEN_HEADER.as_bytes()).await?;
508 stdin.write_all(&content_len_buffer).await?;
509 stdin.write_all("\r\n\r\n".as_bytes()).await?;
510 stdin.write_all(message.as_bytes()).await?;
511 stdin.flush().await?;
512 }
513 drop(output_done_tx);
514 Ok(())
515 }
516
517 /// Initializes a language server by sending the `Initialize` request.
518 /// Note that `options` is used directly to construct [`InitializeParams`], which is why it is owned.
519 ///
520 /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#initialize)
521 pub fn initialize(
522 mut self,
523 options: Option<Value>,
524 cx: &AppContext,
525 ) -> Task<Result<Arc<Self>>> {
526 let root_uri = Url::from_file_path(&self.working_dir).unwrap();
527 #[allow(deprecated)]
528 let params = InitializeParams {
529 process_id: None,
530 root_path: None,
531 root_uri: Some(root_uri.clone()),
532 initialization_options: options,
533 capabilities: ClientCapabilities {
534 workspace: Some(WorkspaceClientCapabilities {
535 configuration: Some(true),
536 did_change_watched_files: Some(DidChangeWatchedFilesClientCapabilities {
537 dynamic_registration: Some(true),
538 relative_pattern_support: Some(true),
539 }),
540 did_change_configuration: Some(DynamicRegistrationClientCapabilities {
541 dynamic_registration: Some(true),
542 }),
543 workspace_folders: Some(true),
544 symbol: Some(WorkspaceSymbolClientCapabilities {
545 resolve_support: None,
546 ..WorkspaceSymbolClientCapabilities::default()
547 }),
548 inlay_hint: Some(InlayHintWorkspaceClientCapabilities {
549 refresh_support: Some(true),
550 }),
551 diagnostic: Some(DiagnosticWorkspaceClientCapabilities {
552 refresh_support: None,
553 }),
554 workspace_edit: Some(WorkspaceEditClientCapabilities {
555 resource_operations: Some(vec![
556 ResourceOperationKind::Create,
557 ResourceOperationKind::Rename,
558 ResourceOperationKind::Delete,
559 ]),
560 document_changes: Some(true),
561 snippet_edit_support: Some(true),
562 ..WorkspaceEditClientCapabilities::default()
563 }),
564 ..Default::default()
565 }),
566 text_document: Some(TextDocumentClientCapabilities {
567 definition: Some(GotoCapability {
568 link_support: Some(true),
569 dynamic_registration: None,
570 }),
571 code_action: Some(CodeActionClientCapabilities {
572 code_action_literal_support: Some(CodeActionLiteralSupport {
573 code_action_kind: CodeActionKindLiteralSupport {
574 value_set: vec![
575 CodeActionKind::REFACTOR.as_str().into(),
576 CodeActionKind::QUICKFIX.as_str().into(),
577 CodeActionKind::SOURCE.as_str().into(),
578 ],
579 },
580 }),
581 data_support: Some(true),
582 resolve_support: Some(CodeActionCapabilityResolveSupport {
583 properties: vec![
584 "kind".to_string(),
585 "diagnostics".to_string(),
586 "isPreferred".to_string(),
587 "disabled".to_string(),
588 "edit".to_string(),
589 "command".to_string(),
590 ],
591 }),
592 ..Default::default()
593 }),
594 completion: Some(CompletionClientCapabilities {
595 completion_item: Some(CompletionItemCapability {
596 snippet_support: Some(true),
597 resolve_support: Some(CompletionItemCapabilityResolveSupport {
598 properties: vec![
599 "documentation".to_string(),
600 "additionalTextEdits".to_string(),
601 ],
602 }),
603 insert_replace_support: Some(true),
604 label_details_support: Some(true),
605 ..Default::default()
606 }),
607 completion_list: Some(CompletionListCapability {
608 item_defaults: Some(vec![
609 "commitCharacters".to_owned(),
610 "editRange".to_owned(),
611 "insertTextMode".to_owned(),
612 "data".to_owned(),
613 ]),
614 }),
615 context_support: Some(true),
616 ..Default::default()
617 }),
618 rename: Some(RenameClientCapabilities {
619 prepare_support: Some(true),
620 ..Default::default()
621 }),
622 hover: Some(HoverClientCapabilities {
623 content_format: Some(vec![MarkupKind::Markdown]),
624 dynamic_registration: None,
625 }),
626 inlay_hint: Some(InlayHintClientCapabilities {
627 resolve_support: Some(InlayHintResolveClientCapabilities {
628 properties: vec![
629 "textEdits".to_string(),
630 "tooltip".to_string(),
631 "label.tooltip".to_string(),
632 "label.location".to_string(),
633 "label.command".to_string(),
634 ],
635 }),
636 dynamic_registration: Some(false),
637 }),
638 publish_diagnostics: Some(PublishDiagnosticsClientCapabilities {
639 related_information: Some(true),
640 ..Default::default()
641 }),
642 formatting: Some(DynamicRegistrationClientCapabilities {
643 dynamic_registration: None,
644 }),
645 on_type_formatting: Some(DynamicRegistrationClientCapabilities {
646 dynamic_registration: None,
647 }),
648 ..Default::default()
649 }),
650 experimental: Some(json!({
651 "serverStatusNotification": true,
652 })),
653 window: Some(WindowClientCapabilities {
654 work_done_progress: Some(true),
655 ..Default::default()
656 }),
657 general: None,
658 },
659 trace: None,
660 workspace_folders: Some(vec![WorkspaceFolder {
661 uri: root_uri,
662 name: Default::default(),
663 }]),
664 client_info: release_channel::ReleaseChannel::try_global(cx).map(|release_channel| {
665 ClientInfo {
666 name: release_channel.display_name().to_string(),
667 version: Some(release_channel::AppVersion::global(cx).to_string()),
668 }
669 }),
670 locale: None,
671 ..Default::default()
672 };
673
674 cx.spawn(|_| async move {
675 let response = self.request::<request::Initialize>(params).await?;
676 if let Some(info) = response.server_info {
677 self.name = info.name.into();
678 }
679 self.capabilities = response.capabilities;
680
681 self.notify::<notification::Initialized>(InitializedParams {})?;
682 Ok(Arc::new(self))
683 })
684 }
685
686 /// Sends a shutdown request to the language server process and prepares the [`LanguageServer`] to be dropped.
687 pub fn shutdown(&self) -> Option<impl 'static + Send + Future<Output = Option<()>>> {
688 if let Some(tasks) = self.io_tasks.lock().take() {
689 let response_handlers = self.response_handlers.clone();
690 let next_id = AtomicI32::new(self.next_id.load(SeqCst));
691 let outbound_tx = self.outbound_tx.clone();
692 let executor = self.executor.clone();
693 let mut output_done = self.output_done_rx.lock().take().unwrap();
694 let shutdown_request = Self::request_internal::<request::Shutdown>(
695 &next_id,
696 &response_handlers,
697 &outbound_tx,
698 &executor,
699 (),
700 );
701 let exit = Self::notify_internal::<notification::Exit>(&outbound_tx, ());
702 outbound_tx.close();
703
704 let server = self.server.clone();
705 let name = self.name.clone();
706 let mut timer = self.executor.timer(SERVER_SHUTDOWN_TIMEOUT).fuse();
707 Some(
708 async move {
709 log::debug!("language server shutdown started");
710
711 select! {
712 request_result = shutdown_request.fuse() => {
713 request_result?;
714 }
715
716 _ = timer => {
717 log::info!("timeout waiting for language server {name} to shutdown");
718 },
719 }
720
721 response_handlers.lock().take();
722 exit?;
723 output_done.recv().await;
724 server.lock().take().map(|mut child| child.kill());
725 log::debug!("language server shutdown finished");
726
727 drop(tasks);
728 anyhow::Ok(())
729 }
730 .log_err(),
731 )
732 } else {
733 None
734 }
735 }
736
737 /// Register a handler to handle incoming LSP notifications.
738 ///
739 /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
740 #[must_use]
741 pub fn on_notification<T, F>(&self, f: F) -> Subscription
742 where
743 T: notification::Notification,
744 F: 'static + Send + FnMut(T::Params, AsyncAppContext),
745 {
746 self.on_custom_notification(T::METHOD, f)
747 }
748
749 /// Register a handler to handle incoming LSP requests.
750 ///
751 /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
752 #[must_use]
753 pub fn on_request<T, F, Fut>(&self, f: F) -> Subscription
754 where
755 T: request::Request,
756 T::Params: 'static + Send,
757 F: 'static + FnMut(T::Params, AsyncAppContext) -> Fut + Send,
758 Fut: 'static + Future<Output = Result<T::Result>>,
759 {
760 self.on_custom_request(T::METHOD, f)
761 }
762
763 /// Registers a handler to inspect all language server process stdio.
764 #[must_use]
765 pub fn on_io<F>(&self, f: F) -> Subscription
766 where
767 F: 'static + Send + FnMut(IoKind, &str),
768 {
769 let id = self.next_id.fetch_add(1, SeqCst);
770 self.io_handlers.lock().insert(id, Box::new(f));
771 Subscription::Io {
772 id,
773 io_handlers: Some(Arc::downgrade(&self.io_handlers)),
774 }
775 }
776
777 /// Removes a request handler registers via [`Self::on_request`].
778 pub fn remove_request_handler<T: request::Request>(&self) {
779 self.notification_handlers.lock().remove(T::METHOD);
780 }
781
782 /// Removes a notification handler registers via [`Self::on_notification`].
783 pub fn remove_notification_handler<T: notification::Notification>(&self) {
784 self.notification_handlers.lock().remove(T::METHOD);
785 }
786
787 /// Checks if a notification handler has been registered via [`Self::on_notification`].
788 pub fn has_notification_handler<T: notification::Notification>(&self) -> bool {
789 self.notification_handlers.lock().contains_key(T::METHOD)
790 }
791
792 #[must_use]
793 fn on_custom_notification<Params, F>(&self, method: &'static str, mut f: F) -> Subscription
794 where
795 F: 'static + FnMut(Params, AsyncAppContext) + Send,
796 Params: DeserializeOwned,
797 {
798 let prev_handler = self.notification_handlers.lock().insert(
799 method,
800 Box::new(move |_, params, cx| {
801 if let Some(params) = serde_json::from_value(params).log_err() {
802 f(params, cx);
803 }
804 }),
805 );
806 assert!(
807 prev_handler.is_none(),
808 "registered multiple handlers for the same LSP method"
809 );
810 Subscription::Notification {
811 method,
812 notification_handlers: Some(self.notification_handlers.clone()),
813 }
814 }
815
816 #[must_use]
817 fn on_custom_request<Params, Res, Fut, F>(&self, method: &'static str, mut f: F) -> Subscription
818 where
819 F: 'static + FnMut(Params, AsyncAppContext) -> Fut + Send,
820 Fut: 'static + Future<Output = Result<Res>>,
821 Params: DeserializeOwned + Send + 'static,
822 Res: Serialize,
823 {
824 let outbound_tx = self.outbound_tx.clone();
825 let prev_handler = self.notification_handlers.lock().insert(
826 method,
827 Box::new(move |id, params, cx| {
828 if let Some(id) = id {
829 match serde_json::from_value(params) {
830 Ok(params) => {
831 let response = f(params, cx.clone());
832 cx.foreground_executor()
833 .spawn({
834 let outbound_tx = outbound_tx.clone();
835 async move {
836 let response = match response.await {
837 Ok(result) => Response {
838 jsonrpc: JSON_RPC_VERSION,
839 id,
840 value: LspResult::Ok(Some(result)),
841 },
842 Err(error) => Response {
843 jsonrpc: JSON_RPC_VERSION,
844 id,
845 value: LspResult::Error(Some(Error {
846 message: error.to_string(),
847 })),
848 },
849 };
850 if let Some(response) =
851 serde_json::to_string(&response).log_err()
852 {
853 outbound_tx.try_send(response).ok();
854 }
855 }
856 })
857 .detach();
858 }
859
860 Err(error) => {
861 log::error!("error deserializing {} request: {:?}", method, error);
862 let response = AnyResponse {
863 jsonrpc: JSON_RPC_VERSION,
864 id,
865 result: None,
866 error: Some(Error {
867 message: error.to_string(),
868 }),
869 };
870 if let Some(response) = serde_json::to_string(&response).log_err() {
871 outbound_tx.try_send(response).ok();
872 }
873 }
874 }
875 }
876 }),
877 );
878 assert!(
879 prev_handler.is_none(),
880 "registered multiple handlers for the same LSP method"
881 );
882 Subscription::Notification {
883 method,
884 notification_handlers: Some(self.notification_handlers.clone()),
885 }
886 }
887
888 /// Get the name of the running language server.
889 pub fn name(&self) -> &str {
890 &self.name
891 }
892
893 /// Get the reported capabilities of the running language server.
894 pub fn capabilities(&self) -> &ServerCapabilities {
895 &self.capabilities
896 }
897
898 /// Get the id of the running language server.
899 pub fn server_id(&self) -> LanguageServerId {
900 self.server_id
901 }
902
903 /// Get the root path of the project the language server is running against.
904 pub fn root_path(&self) -> &PathBuf {
905 &self.root_path
906 }
907
908 /// Sends a RPC request to the language server.
909 ///
910 /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage)
911 pub fn request<T: request::Request>(
912 &self,
913 params: T::Params,
914 ) -> impl LspRequestFuture<Result<T::Result>>
915 where
916 T::Result: 'static + Send,
917 {
918 Self::request_internal::<T>(
919 &self.next_id,
920 &self.response_handlers,
921 &self.outbound_tx,
922 &self.executor,
923 params,
924 )
925 }
926
927 fn request_internal<T: request::Request>(
928 next_id: &AtomicI32,
929 response_handlers: &Mutex<Option<HashMap<RequestId, ResponseHandler>>>,
930 outbound_tx: &channel::Sender<String>,
931 executor: &BackgroundExecutor,
932 params: T::Params,
933 ) -> impl LspRequestFuture<Result<T::Result>>
934 where
935 T::Result: 'static + Send,
936 {
937 let id = next_id.fetch_add(1, SeqCst);
938 let message = serde_json::to_string(&Request {
939 jsonrpc: JSON_RPC_VERSION,
940 id: RequestId::Int(id),
941 method: T::METHOD,
942 params,
943 })
944 .unwrap();
945
946 let (tx, rx) = oneshot::channel();
947 let handle_response = response_handlers
948 .lock()
949 .as_mut()
950 .ok_or_else(|| anyhow!("server shut down"))
951 .map(|handlers| {
952 let executor = executor.clone();
953 handlers.insert(
954 RequestId::Int(id),
955 Box::new(move |result| {
956 executor
957 .spawn(async move {
958 let response = match result {
959 Ok(response) => match serde_json::from_str(&response) {
960 Ok(deserialized) => Ok(deserialized),
961 Err(error) => {
962 log::error!("failed to deserialize response from language server: {}. response from language server: {:?}", error, response);
963 Err(error).context("failed to deserialize response")
964 }
965 }
966 Err(error) => Err(anyhow!("{}", error.message)),
967 };
968 _ = tx.send(response);
969 })
970 .detach();
971 }),
972 );
973 });
974
975 let send = outbound_tx
976 .try_send(message)
977 .context("failed to write to language server's stdin");
978
979 let outbound_tx = outbound_tx.downgrade();
980 let mut timeout = executor.timer(LSP_REQUEST_TIMEOUT).fuse();
981 let started = Instant::now();
982 LspRequest::new(id, async move {
983 handle_response?;
984 send?;
985
986 let cancel_on_drop = util::defer(move || {
987 if let Some(outbound_tx) = outbound_tx.upgrade() {
988 Self::notify_internal::<notification::Cancel>(
989 &outbound_tx,
990 CancelParams {
991 id: NumberOrString::Number(id),
992 },
993 )
994 .log_err();
995 }
996 });
997
998 let method = T::METHOD;
999 select! {
1000 response = rx.fuse() => {
1001 let elapsed = started.elapsed();
1002 log::trace!("Took {elapsed:?} to receive response to {method:?} id {id}");
1003 cancel_on_drop.abort();
1004 response?
1005 }
1006
1007 _ = timeout => {
1008 log::error!("Cancelled LSP request task for {method:?} id {id} which took over {LSP_REQUEST_TIMEOUT:?}");
1009 anyhow::bail!("LSP request timeout");
1010 }
1011 }
1012 })
1013 }
1014
1015 /// Sends a RPC notification to the language server.
1016 ///
1017 /// [LSP Specification](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage)
1018 pub fn notify<T: notification::Notification>(&self, params: T::Params) -> Result<()> {
1019 Self::notify_internal::<T>(&self.outbound_tx, params)
1020 }
1021
1022 fn notify_internal<T: notification::Notification>(
1023 outbound_tx: &channel::Sender<String>,
1024 params: T::Params,
1025 ) -> Result<()> {
1026 let message = serde_json::to_string(&Notification {
1027 jsonrpc: JSON_RPC_VERSION,
1028 method: T::METHOD,
1029 params,
1030 })
1031 .unwrap();
1032 outbound_tx.try_send(message)?;
1033 Ok(())
1034 }
1035}
1036
1037impl Drop for LanguageServer {
1038 fn drop(&mut self) {
1039 if let Some(shutdown) = self.shutdown() {
1040 self.executor.spawn(shutdown).detach();
1041 }
1042 }
1043}
1044
1045impl Subscription {
1046 /// Detaching a subscription handle prevents it from unsubscribing on drop.
1047 pub fn detach(&mut self) {
1048 match self {
1049 Subscription::Notification {
1050 notification_handlers,
1051 ..
1052 } => *notification_handlers = None,
1053 Subscription::Io { io_handlers, .. } => *io_handlers = None,
1054 }
1055 }
1056}
1057
1058impl fmt::Display for LanguageServerId {
1059 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1060 self.0.fmt(f)
1061 }
1062}
1063
1064impl fmt::Debug for LanguageServer {
1065 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1066 f.debug_struct("LanguageServer")
1067 .field("id", &self.server_id.0)
1068 .field("name", &self.name)
1069 .finish_non_exhaustive()
1070 }
1071}
1072
1073impl Drop for Subscription {
1074 fn drop(&mut self) {
1075 match self {
1076 Subscription::Notification {
1077 method,
1078 notification_handlers,
1079 } => {
1080 if let Some(handlers) = notification_handlers {
1081 handlers.lock().remove(method);
1082 }
1083 }
1084 Subscription::Io { id, io_handlers } => {
1085 if let Some(io_handlers) = io_handlers.as_ref().and_then(|h| h.upgrade()) {
1086 io_handlers.lock().remove(id);
1087 }
1088 }
1089 }
1090 }
1091}
1092
1093/// Mock language server for use in tests.
1094#[cfg(any(test, feature = "test-support"))]
1095#[derive(Clone)]
1096pub struct FakeLanguageServer {
1097 pub binary: LanguageServerBinary,
1098 pub server: Arc<LanguageServer>,
1099 notifications_rx: channel::Receiver<(String, String)>,
1100}
1101
1102#[cfg(any(test, feature = "test-support"))]
1103impl FakeLanguageServer {
1104 /// Construct a fake language server.
1105 pub fn new(
1106 server_id: LanguageServerId,
1107 binary: LanguageServerBinary,
1108 name: String,
1109 capabilities: ServerCapabilities,
1110 cx: AsyncAppContext,
1111 ) -> (LanguageServer, FakeLanguageServer) {
1112 let (stdin_writer, stdin_reader) = async_pipe::pipe();
1113 let (stdout_writer, stdout_reader) = async_pipe::pipe();
1114 let (notifications_tx, notifications_rx) = channel::unbounded();
1115
1116 let mut server = LanguageServer::new_internal(
1117 server_id,
1118 stdin_writer,
1119 stdout_reader,
1120 None::<async_pipe::PipeReader>,
1121 Arc::new(Mutex::new(None)),
1122 None,
1123 Path::new("/"),
1124 Path::new("/"),
1125 None,
1126 cx.clone(),
1127 |_| {},
1128 );
1129 server.name = name.as_str().into();
1130 let fake = FakeLanguageServer {
1131 binary,
1132 server: Arc::new({
1133 let mut server = LanguageServer::new_internal(
1134 server_id,
1135 stdout_writer,
1136 stdin_reader,
1137 None::<async_pipe::PipeReader>,
1138 Arc::new(Mutex::new(None)),
1139 None,
1140 Path::new("/"),
1141 Path::new("/"),
1142 None,
1143 cx,
1144 move |msg| {
1145 notifications_tx
1146 .try_send((
1147 msg.method.to_string(),
1148 msg.params.unwrap_or(Value::Null).to_string(),
1149 ))
1150 .ok();
1151 },
1152 );
1153 server.name = name.as_str().into();
1154 server
1155 }),
1156 notifications_rx,
1157 };
1158 fake.handle_request::<request::Initialize, _, _>({
1159 let capabilities = capabilities;
1160 move |_, _| {
1161 let capabilities = capabilities.clone();
1162 let name = name.clone();
1163 async move {
1164 Ok(InitializeResult {
1165 capabilities,
1166 server_info: Some(ServerInfo {
1167 name,
1168 ..Default::default()
1169 }),
1170 })
1171 }
1172 }
1173 });
1174
1175 (server, fake)
1176 }
1177}
1178
1179#[cfg(any(test, feature = "test-support"))]
1180impl LanguageServer {
1181 pub fn full_capabilities() -> ServerCapabilities {
1182 ServerCapabilities {
1183 document_highlight_provider: Some(OneOf::Left(true)),
1184 code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
1185 document_formatting_provider: Some(OneOf::Left(true)),
1186 document_range_formatting_provider: Some(OneOf::Left(true)),
1187 definition_provider: Some(OneOf::Left(true)),
1188 implementation_provider: Some(ImplementationProviderCapability::Simple(true)),
1189 type_definition_provider: Some(TypeDefinitionProviderCapability::Simple(true)),
1190 ..Default::default()
1191 }
1192 }
1193}
1194
1195#[cfg(any(test, feature = "test-support"))]
1196impl FakeLanguageServer {
1197 /// See [`LanguageServer::notify`].
1198 pub fn notify<T: notification::Notification>(&self, params: T::Params) {
1199 self.server.notify::<T>(params).ok();
1200 }
1201
1202 /// See [`LanguageServer::request`].
1203 pub async fn request<T>(&self, params: T::Params) -> Result<T::Result>
1204 where
1205 T: request::Request,
1206 T::Result: 'static + Send,
1207 {
1208 self.server.executor.start_waiting();
1209 self.server.request::<T>(params).await
1210 }
1211
1212 /// Attempts [`Self::try_receive_notification`], unwrapping if it has not received the specified type yet.
1213 pub async fn receive_notification<T: notification::Notification>(&mut self) -> T::Params {
1214 self.server.executor.start_waiting();
1215 self.try_receive_notification::<T>().await.unwrap()
1216 }
1217
1218 /// Consumes the notification channel until it finds a notification for the specified type.
1219 pub async fn try_receive_notification<T: notification::Notification>(
1220 &mut self,
1221 ) -> Option<T::Params> {
1222 use futures::StreamExt as _;
1223
1224 loop {
1225 let (method, params) = self.notifications_rx.next().await?;
1226 if method == T::METHOD {
1227 return Some(serde_json::from_str::<T::Params>(¶ms).unwrap());
1228 } else {
1229 log::info!("skipping message in fake language server {:?}", params);
1230 }
1231 }
1232 }
1233
1234 /// Registers a handler for a specific kind of request. Removes any existing handler for specified request type.
1235 pub fn handle_request<T, F, Fut>(
1236 &self,
1237 mut handler: F,
1238 ) -> futures::channel::mpsc::UnboundedReceiver<()>
1239 where
1240 T: 'static + request::Request,
1241 T::Params: 'static + Send,
1242 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext) -> Fut,
1243 Fut: 'static + Send + Future<Output = Result<T::Result>>,
1244 {
1245 let (responded_tx, responded_rx) = futures::channel::mpsc::unbounded();
1246 self.server.remove_request_handler::<T>();
1247 self.server
1248 .on_request::<T, _, _>(move |params, cx| {
1249 let result = handler(params, cx.clone());
1250 let responded_tx = responded_tx.clone();
1251 let executor = cx.background_executor().clone();
1252 async move {
1253 executor.simulate_random_delay().await;
1254 let result = result.await;
1255 responded_tx.unbounded_send(()).ok();
1256 result
1257 }
1258 })
1259 .detach();
1260 responded_rx
1261 }
1262
1263 /// Registers a handler for a specific kind of notification. Removes any existing handler for specified notification type.
1264 pub fn handle_notification<T, F>(
1265 &self,
1266 mut handler: F,
1267 ) -> futures::channel::mpsc::UnboundedReceiver<()>
1268 where
1269 T: 'static + notification::Notification,
1270 T::Params: 'static + Send,
1271 F: 'static + Send + FnMut(T::Params, gpui::AsyncAppContext),
1272 {
1273 let (handled_tx, handled_rx) = futures::channel::mpsc::unbounded();
1274 self.server.remove_notification_handler::<T>();
1275 self.server
1276 .on_notification::<T, _>(move |params, cx| {
1277 handler(params, cx.clone());
1278 handled_tx.unbounded_send(()).ok();
1279 })
1280 .detach();
1281 handled_rx
1282 }
1283
1284 /// Removes any existing handler for specified notification type.
1285 pub fn remove_request_handler<T>(&mut self)
1286 where
1287 T: 'static + request::Request,
1288 {
1289 self.server.remove_request_handler::<T>();
1290 }
1291
1292 /// Simulate that the server has started work and notifies about its progress with the specified token.
1293 pub async fn start_progress(&self, token: impl Into<String>) {
1294 self.start_progress_with(token, Default::default()).await
1295 }
1296
1297 pub async fn start_progress_with(
1298 &self,
1299 token: impl Into<String>,
1300 progress: WorkDoneProgressBegin,
1301 ) {
1302 let token = token.into();
1303 self.request::<request::WorkDoneProgressCreate>(WorkDoneProgressCreateParams {
1304 token: NumberOrString::String(token.clone()),
1305 })
1306 .await
1307 .unwrap();
1308 self.notify::<notification::Progress>(ProgressParams {
1309 token: NumberOrString::String(token),
1310 value: ProgressParamsValue::WorkDone(WorkDoneProgress::Begin(progress)),
1311 });
1312 }
1313
1314 /// Simulate that the server has completed work and notifies about that with the specified token.
1315 pub fn end_progress(&self, token: impl Into<String>) {
1316 self.notify::<notification::Progress>(ProgressParams {
1317 token: NumberOrString::String(token.into()),
1318 value: ProgressParamsValue::WorkDone(WorkDoneProgress::End(Default::default())),
1319 });
1320 }
1321}
1322
1323#[cfg(test)]
1324mod tests {
1325 use super::*;
1326 use gpui::{SemanticVersion, TestAppContext};
1327 use std::str::FromStr;
1328
1329 #[ctor::ctor]
1330 fn init_logger() {
1331 if std::env::var("RUST_LOG").is_ok() {
1332 env_logger::init();
1333 }
1334 }
1335
1336 #[gpui::test]
1337 async fn test_fake(cx: &mut TestAppContext) {
1338 cx.update(|cx| {
1339 release_channel::init(SemanticVersion::default(), cx);
1340 });
1341 let (server, mut fake) = FakeLanguageServer::new(
1342 LanguageServerId(0),
1343 LanguageServerBinary {
1344 path: "path/to/language-server".into(),
1345 arguments: vec![],
1346 env: None,
1347 },
1348 "the-lsp".to_string(),
1349 Default::default(),
1350 cx.to_async(),
1351 );
1352
1353 let (message_tx, message_rx) = channel::unbounded();
1354 let (diagnostics_tx, diagnostics_rx) = channel::unbounded();
1355 server
1356 .on_notification::<notification::ShowMessage, _>(move |params, _| {
1357 message_tx.try_send(params).unwrap()
1358 })
1359 .detach();
1360 server
1361 .on_notification::<notification::PublishDiagnostics, _>(move |params, _| {
1362 diagnostics_tx.try_send(params).unwrap()
1363 })
1364 .detach();
1365
1366 let server = cx.update(|cx| server.initialize(None, cx)).await.unwrap();
1367 server
1368 .notify::<notification::DidOpenTextDocument>(DidOpenTextDocumentParams {
1369 text_document: TextDocumentItem::new(
1370 Url::from_str("file://a/b").unwrap(),
1371 "rust".to_string(),
1372 0,
1373 "".to_string(),
1374 ),
1375 })
1376 .unwrap();
1377 assert_eq!(
1378 fake.receive_notification::<notification::DidOpenTextDocument>()
1379 .await
1380 .text_document
1381 .uri
1382 .as_str(),
1383 "file://a/b"
1384 );
1385
1386 fake.notify::<notification::ShowMessage>(ShowMessageParams {
1387 typ: MessageType::ERROR,
1388 message: "ok".to_string(),
1389 });
1390 fake.notify::<notification::PublishDiagnostics>(PublishDiagnosticsParams {
1391 uri: Url::from_str("file://b/c").unwrap(),
1392 version: Some(5),
1393 diagnostics: vec![],
1394 });
1395 assert_eq!(message_rx.recv().await.unwrap().message, "ok");
1396 assert_eq!(
1397 diagnostics_rx.recv().await.unwrap().uri.as_str(),
1398 "file://b/c"
1399 );
1400
1401 fake.handle_request::<request::Shutdown, _, _>(|_, _| async move { Ok(()) });
1402
1403 drop(server);
1404 fake.receive_notification::<notification::Exit>().await;
1405 }
1406
1407 #[gpui::test]
1408 fn test_deserialize_string_digit_id() {
1409 let json = r#"{"jsonrpc":"2.0","id":"2","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1410 let notification = serde_json::from_str::<AnyNotification>(json)
1411 .expect("message with string id should be parsed");
1412 let expected_id = RequestId::Str("2".to_string());
1413 assert_eq!(notification.id, Some(expected_id));
1414 }
1415
1416 #[gpui::test]
1417 fn test_deserialize_string_id() {
1418 let json = r#"{"jsonrpc":"2.0","id":"anythingAtAll","method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1419 let notification = serde_json::from_str::<AnyNotification>(json)
1420 .expect("message with string id should be parsed");
1421 let expected_id = RequestId::Str("anythingAtAll".to_string());
1422 assert_eq!(notification.id, Some(expected_id));
1423 }
1424
1425 #[gpui::test]
1426 fn test_deserialize_int_id() {
1427 let json = r#"{"jsonrpc":"2.0","id":2,"method":"workspace/configuration","params":{"items":[{"scopeUri":"file:///Users/mph/Devel/personal/hello-scala/","section":"metals"}]}}"#;
1428 let notification = serde_json::from_str::<AnyNotification>(json)
1429 .expect("message with string id should be parsed");
1430 let expected_id = RequestId::Int(2);
1431 assert_eq!(notification.id, Some(expected_id));
1432 }
1433
1434 #[test]
1435 fn test_serialize_has_no_nulls() {
1436 // Ensure we're not setting both result and error variants. (ticket #10595)
1437 let no_tag = Response::<u32> {
1438 jsonrpc: "",
1439 id: RequestId::Int(0),
1440 value: LspResult::Ok(None),
1441 };
1442 assert_eq!(
1443 serde_json::to_string(&no_tag).unwrap(),
1444 "{\"jsonrpc\":\"\",\"id\":0,\"result\":null}"
1445 );
1446 let no_tag = Response::<u32> {
1447 jsonrpc: "",
1448 id: RequestId::Int(0),
1449 value: LspResult::Error(None),
1450 };
1451 assert_eq!(
1452 serde_json::to_string(&no_tag).unwrap(),
1453 "{\"jsonrpc\":\"\",\"id\":0,\"error\":null}"
1454 );
1455 }
1456}