semantic_tokens.rs

  1use std::{collections::hash_map, ops::Range, slice::ChunksExact, sync::Arc};
  2
  3use anyhow::Result;
  4
  5use clock::Global;
  6use collections::HashMap;
  7use futures::{
  8    FutureExt as _,
  9    future::{Shared, join_all},
 10};
 11use gpui::{App, AppContext, AsyncApp, Context, Entity, ReadGlobal as _, SharedString, Task};
 12use itertools::Itertools;
 13use language::{Buffer, LanguageName, language_settings::all_language_settings};
 14use lsp::{AdapterServerCapabilities, LanguageServerId};
 15use rpc::{TypedEnvelope, proto};
 16use settings::{SemanticTokenRule, SemanticTokenRules, Settings as _, SettingsStore};
 17use smol::future::yield_now;
 18use text::{Anchor, Bias, OffsetUtf16, PointUtf16, Unclipped};
 19use util::ResultExt as _;
 20
 21use crate::{
 22    LanguageServerToQuery, LspStore, LspStoreEvent,
 23    lsp_command::{
 24        LspCommand, SemanticTokensDelta, SemanticTokensEdit, SemanticTokensFull,
 25        SemanticTokensResponse,
 26    },
 27    project_settings::ProjectSettings,
 28};
 29
 30pub(super) struct SemanticTokenConfig {
 31    stylizers: HashMap<(LanguageServerId, Option<LanguageName>), SemanticTokenStylizer>,
 32    rules: SemanticTokenRules,
 33    global_mode: settings::SemanticTokens,
 34}
 35
 36impl SemanticTokenConfig {
 37    pub(super) fn new(cx: &App) -> Self {
 38        Self {
 39            stylizers: HashMap::default(),
 40            rules: ProjectSettings::get_global(cx)
 41                .global_lsp_settings
 42                .semantic_token_rules
 43                .clone(),
 44            global_mode: all_language_settings(None, cx).defaults.semantic_tokens,
 45        }
 46    }
 47
 48    pub(super) fn remove_server_data(&mut self, server_id: LanguageServerId) {
 49        self.stylizers.retain(|&(id, _), _| id != server_id);
 50    }
 51
 52    pub(super) fn update_rules(&mut self, new_rules: SemanticTokenRules) -> bool {
 53        if new_rules != self.rules {
 54            self.rules = new_rules;
 55            self.stylizers.clear();
 56            true
 57        } else {
 58            false
 59        }
 60    }
 61
 62    pub(super) fn update_global_mode(&mut self, new_mode: settings::SemanticTokens) -> bool {
 63        if new_mode != self.global_mode {
 64            self.global_mode = new_mode;
 65            true
 66        } else {
 67            false
 68        }
 69    }
 70}
 71
 72#[derive(Debug, Clone, Copy)]
 73pub struct RefreshForServer {
 74    pub server_id: LanguageServerId,
 75    pub request_id: Option<usize>,
 76}
 77
 78impl LspStore {
 79    pub fn semantic_tokens(
 80        &mut self,
 81        buffer: Entity<Buffer>,
 82        refresh: Option<RefreshForServer>,
 83        cx: &mut Context<Self>,
 84    ) -> SemanticTokensTask {
 85        let version_queried_for = buffer.read(cx).version();
 86        let latest_lsp_data = self.latest_lsp_data(&buffer, cx);
 87        let semantic_tokens_data = latest_lsp_data.semantic_tokens.get_or_insert_default();
 88        if let Some(refresh) = refresh {
 89            let mut invalidate_cache = true;
 90            match semantic_tokens_data
 91                .latest_invalidation_requests
 92                .entry(refresh.server_id)
 93            {
 94                hash_map::Entry::Occupied(mut o) => {
 95                    if refresh.request_id > *o.get() {
 96                        o.insert(refresh.request_id);
 97                    } else {
 98                        invalidate_cache = false;
 99                    }
100                }
101                hash_map::Entry::Vacant(v) => {
102                    v.insert(refresh.request_id);
103                }
104            }
105
106            if invalidate_cache {
107                let SemanticTokensData {
108                    raw_tokens,
109                    latest_invalidation_requests: _,
110                    update,
111                } = semantic_tokens_data;
112                *update = None;
113                raw_tokens.servers.clear();
114            }
115        }
116
117        if let Some((updating_for, task)) = &semantic_tokens_data.update
118            && !version_queried_for.changed_since(updating_for)
119        {
120            return task.clone();
121        }
122
123        let new_tokens = self.fetch_semantic_tokens_for_buffer(
124            &buffer,
125            refresh.map(|refresh| refresh.server_id),
126            cx,
127        );
128
129        let task_buffer = buffer.clone();
130        let task_version_queried_for = version_queried_for.clone();
131        let task = cx
132            .spawn(async move |lsp_store, cx| {
133                let buffer = task_buffer;
134                let version_queried_for = task_version_queried_for;
135                let res = if let Some(new_tokens) = new_tokens.await {
136                    let (raw_tokens, buffer_snapshot) = lsp_store
137                        .update(cx, |lsp_store, cx| {
138                            let lsp_data = lsp_store.latest_lsp_data(&buffer, cx);
139                            let semantic_tokens_data =
140                                lsp_data.semantic_tokens.get_or_insert_default();
141
142                            if version_queried_for == lsp_data.buffer_version {
143                                for (server_id, new_tokens_response) in new_tokens {
144                                    match new_tokens_response {
145                                        SemanticTokensResponse::Full { data, result_id } => {
146                                            semantic_tokens_data.raw_tokens.servers.insert(
147                                                server_id,
148                                                Arc::new(ServerSemanticTokens::from_full(
149                                                    data, result_id,
150                                                )),
151                                            );
152                                        }
153                                        SemanticTokensResponse::Delta { edits, result_id } => {
154                                            if let Some(tokens) = semantic_tokens_data
155                                                .raw_tokens
156                                                .servers
157                                                .get_mut(&server_id)
158                                            {
159                                                let tokens = Arc::make_mut(tokens);
160                                                tokens.result_id = result_id;
161                                                tokens.apply(&edits);
162                                            }
163                                        }
164                                    }
165                                }
166                            }
167                            let buffer_snapshot =
168                                buffer.read_with(cx, |buffer, _| buffer.snapshot());
169                            (semantic_tokens_data.raw_tokens.clone(), buffer_snapshot)
170                        })
171                        .map_err(Arc::new)?;
172                    Some(raw_to_buffer_semantic_tokens(raw_tokens, &buffer_snapshot).await)
173                } else {
174                    lsp_store.update(cx, |lsp_store, cx| {
175                        if let Some(current_lsp_data) =
176                            lsp_store.current_lsp_data(buffer.read(cx).remote_id())
177                        {
178                            if current_lsp_data.buffer_version == version_queried_for {
179                                current_lsp_data.semantic_tokens = None;
180                            }
181                        }
182                    })?;
183                    None
184                };
185                Ok(BufferSemanticTokens { tokens: res })
186            })
187            .shared();
188
189        self.latest_lsp_data(&buffer, cx)
190            .semantic_tokens
191            .get_or_insert_default()
192            .update = Some((version_queried_for, task.clone()));
193
194        task
195    }
196
197    pub(super) fn fetch_semantic_tokens_for_buffer(
198        &mut self,
199        buffer: &Entity<Buffer>,
200        for_server: Option<LanguageServerId>,
201        cx: &mut Context<Self>,
202    ) -> Task<Option<HashMap<LanguageServerId, SemanticTokensResponse>>> {
203        if let Some((client, upstream_project_id)) = self.upstream_client() {
204            let request = SemanticTokensFull { for_server };
205            if !self.is_capable_for_proto_request(buffer, &request, cx) {
206                return Task::ready(None);
207            }
208
209            let request_timeout = ProjectSettings::get_global(cx)
210                .global_lsp_settings
211                .get_request_timeout();
212            let request_task = client.request_lsp(
213                upstream_project_id,
214                None,
215                request_timeout,
216                cx.background_executor().clone(),
217                request.to_proto(upstream_project_id, buffer.read(cx)),
218            );
219            let buffer = buffer.clone();
220            cx.spawn(async move |weak_lsp_store, cx| {
221                let lsp_store = weak_lsp_store.upgrade()?;
222                let tokens = join_all(
223                    request_task
224                        .await
225                        .log_err()
226                        .flatten()
227                        .map(|response| response.payload)
228                        .unwrap_or_default()
229                        .into_iter()
230                        .map(|response| {
231                            let server_id = LanguageServerId::from_proto(response.server_id);
232                            let response = request.response_from_proto(
233                                response.response,
234                                lsp_store.clone(),
235                                buffer.clone(),
236                                cx.clone(),
237                            );
238                            async move {
239                                match response.await {
240                                    Ok(tokens) => Some((server_id, tokens)),
241                                    Err(e) => {
242                                        log::error!("Failed to query remote semantic tokens for server {server_id:?}: {e:#}");
243                                        None
244                                    }
245                                }
246                            }
247                        }),
248                )
249                .await
250                .into_iter()
251                .flatten()
252                .collect();
253                Some(tokens)
254            })
255        } else {
256            let token_tasks = self
257                .local_lsp_servers_for_buffer(&buffer, cx)
258                .into_iter()
259                .filter(|&server_id| {
260                    for_server.is_none_or(|for_server_id| for_server_id == server_id)
261                })
262                .filter_map(|server_id| {
263                    let capabilities = AdapterServerCapabilities {
264                        server_capabilities: self.lsp_server_capabilities.get(&server_id)?.clone(),
265                        code_action_kinds: None,
266                    };
267                    let request_task = match self.semantic_tokens_result_id(server_id, buffer, cx) {
268                        Some(result_id) => {
269                            let delta_request = SemanticTokensDelta {
270                                previous_result_id: result_id,
271                            };
272                            if !delta_request.check_capabilities(capabilities.clone()) {
273                                let full_request = SemanticTokensFull {
274                                    for_server: Some(server_id),
275                                };
276                                if !full_request.check_capabilities(capabilities) {
277                                    return None;
278                                }
279
280                                self.request_lsp(
281                                    buffer.clone(),
282                                    LanguageServerToQuery::Other(server_id),
283                                    full_request,
284                                    cx,
285                                )
286                            } else {
287                                self.request_lsp(
288                                    buffer.clone(),
289                                    LanguageServerToQuery::Other(server_id),
290                                    delta_request,
291                                    cx,
292                                )
293                            }
294                        }
295                        None => {
296                            let request = SemanticTokensFull {
297                                for_server: Some(server_id),
298                            };
299                            if !request.check_capabilities(capabilities) {
300                                return None;
301                            }
302                            self.request_lsp(
303                                buffer.clone(),
304                                LanguageServerToQuery::Other(server_id),
305                                request,
306                                cx,
307                            )
308                        }
309                    };
310                    Some(async move { (server_id, request_task.await) })
311                })
312                .collect::<Vec<_>>();
313            if token_tasks.is_empty() {
314                return Task::ready(None);
315            }
316
317            cx.background_spawn(async move {
318                Some(
319                    join_all(token_tasks)
320                        .await
321                        .into_iter()
322                        .flat_map(|(server_id, response)| {
323                            match response {
324                                Ok(tokens) => Some((server_id, tokens)),
325                                Err(e) => {
326                                    log::error!("Failed to query remote semantic tokens for server {server_id:?}: {e:#}");
327                                    None
328                                }
329                            }
330                        })
331                        .collect()
332                )
333            })
334        }
335    }
336
337    pub(crate) async fn handle_refresh_semantic_tokens(
338        lsp_store: Entity<Self>,
339        envelope: TypedEnvelope<proto::RefreshSemanticTokens>,
340        mut cx: AsyncApp,
341    ) -> Result<proto::Ack> {
342        lsp_store.update(&mut cx, |_, cx| {
343            cx.emit(LspStoreEvent::RefreshSemanticTokens {
344                server_id: LanguageServerId::from_proto(envelope.payload.server_id),
345                request_id: envelope.payload.request_id.map(|id| id as usize),
346            });
347        });
348        Ok(proto::Ack {})
349    }
350
351    fn semantic_tokens_result_id(
352        &mut self,
353        server_id: LanguageServerId,
354        buffer: &Entity<Buffer>,
355        cx: &mut App,
356    ) -> Option<SharedString> {
357        self.latest_lsp_data(buffer, cx)
358            .semantic_tokens
359            .as_ref()?
360            .raw_tokens
361            .servers
362            .get(&server_id)?
363            .result_id
364            .clone()
365    }
366
367    pub fn get_or_create_token_stylizer(
368        &mut self,
369        server_id: LanguageServerId,
370        language: Option<&LanguageName>,
371        cx: &mut App,
372    ) -> Option<&SemanticTokenStylizer> {
373        let stylizer = match self
374            .semantic_token_config
375            .stylizers
376            .entry((server_id, language.cloned()))
377        {
378            hash_map::Entry::Occupied(o) => o.into_mut(),
379            hash_map::Entry::Vacant(v) => {
380                let tokens_provider = self
381                    .lsp_server_capabilities
382                    .get(&server_id)?
383                    .semantic_tokens_provider
384                    .as_ref()?;
385                let legend = match tokens_provider {
386                    lsp::SemanticTokensServerCapabilities::SemanticTokensOptions(opts) => {
387                        &opts.legend
388                    }
389                    lsp::SemanticTokensServerCapabilities::SemanticTokensRegistrationOptions(
390                        opts,
391                    ) => &opts.semantic_tokens_options.legend,
392                };
393                let language_rules = language.and_then(|language| {
394                    SettingsStore::global(cx).language_semantic_token_rules(language.as_ref())
395                });
396                let stylizer = SemanticTokenStylizer::new(server_id, legend, language_rules, cx);
397                v.insert(stylizer)
398            }
399        };
400        Some(stylizer)
401    }
402}
403
404pub type SemanticTokensTask =
405    Shared<Task<std::result::Result<BufferSemanticTokens, Arc<anyhow::Error>>>>;
406
407#[derive(Debug, Default, Clone)]
408pub struct BufferSemanticTokens {
409    pub tokens: Option<HashMap<LanguageServerId, Arc<[BufferSemanticToken]>>>,
410}
411
412#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
413pub struct TokenType(pub u32);
414
415#[derive(Debug, Clone)]
416pub struct BufferSemanticToken {
417    pub range: Range<Anchor>,
418    pub token_type: TokenType,
419    pub token_modifiers: u32,
420}
421
422pub struct SemanticTokenStylizer {
423    server_id: LanguageServerId,
424    rules_by_token_type: HashMap<TokenType, Vec<SemanticTokenRule>>,
425    token_type_names: HashMap<TokenType, SharedString>,
426    modifier_mask: HashMap<SharedString, u32>,
427}
428
429impl SemanticTokenStylizer {
430    pub fn new(
431        server_id: LanguageServerId,
432        legend: &lsp::SemanticTokensLegend,
433        language_rules: Option<&SemanticTokenRules>,
434        cx: &App,
435    ) -> Self {
436        let token_types: HashMap<TokenType, SharedString> = legend
437            .token_types
438            .iter()
439            .enumerate()
440            .map(|(i, token_type)| {
441                (
442                    TokenType(i as u32),
443                    SharedString::from(token_type.as_str().to_string()),
444                )
445            })
446            .collect();
447        let modifier_mask: HashMap<SharedString, u32> = legend
448            .token_modifiers
449            .iter()
450            .enumerate()
451            .map(|(i, modifier)| (SharedString::from(modifier.as_str().to_string()), 1 << i))
452            .collect();
453
454        let global_rules = &ProjectSettings::get_global(cx)
455            .global_lsp_settings
456            .semantic_token_rules;
457
458        let rules_by_token_type = token_types
459            .iter()
460            .map(|(index, token_type_name)| {
461                let filter = |rule: &&SemanticTokenRule| {
462                    rule.token_type
463                        .as_ref()
464                        .is_none_or(|rule_token_type| rule_token_type == token_type_name.as_ref())
465                };
466                let matching_rules: Vec<SemanticTokenRule> = global_rules
467                    .rules
468                    .iter()
469                    .chain(language_rules.into_iter().flat_map(|lr| &lr.rules))
470                    .rev()
471                    .filter(filter)
472                    .cloned()
473                    .collect();
474                (*index, matching_rules)
475            })
476            .collect();
477
478        SemanticTokenStylizer {
479            server_id,
480            rules_by_token_type,
481            token_type_names: token_types,
482            modifier_mask,
483        }
484    }
485
486    pub fn server_id(&self) -> LanguageServerId {
487        self.server_id
488    }
489
490    pub fn token_type_name(&self, token_type: TokenType) -> Option<&SharedString> {
491        self.token_type_names.get(&token_type)
492    }
493
494    pub fn has_modifier(&self, token_modifiers: u32, modifier: &str) -> bool {
495        let Some(mask) = self.modifier_mask.get(modifier) else {
496            return false;
497        };
498        (token_modifiers & mask) != 0
499    }
500
501    pub fn token_modifiers(&self, token_modifiers: u32) -> Option<String> {
502        let modifiers: Vec<&str> = self
503            .modifier_mask
504            .iter()
505            .filter(|(_, mask)| (token_modifiers & *mask) != 0)
506            .map(|(name, _)| name.as_ref())
507            .collect();
508        if modifiers.is_empty() {
509            None
510        } else {
511            Some(modifiers.join(", "))
512        }
513    }
514
515    pub fn rules_for_token(&self, token_type: TokenType) -> Option<&[SemanticTokenRule]> {
516        self.rules_by_token_type
517            .get(&token_type)
518            .map(|v| v.as_slice())
519    }
520}
521
522async fn raw_to_buffer_semantic_tokens(
523    raw_tokens: RawSemanticTokens,
524    buffer_snapshot: &text::BufferSnapshot,
525) -> HashMap<LanguageServerId, Arc<[BufferSemanticToken]>> {
526    let mut res = HashMap::default();
527    for (&server_id, server_tokens) in &raw_tokens.servers {
528        // We don't do `collect` here due to the filter map not pre-allocating
529        // we'd rather over allocate here than not since we have to re-allocate into an arc slice anyways
530        let mut buffer_tokens = Vec::with_capacity(server_tokens.data.len() / 5);
531        // 5000 was chosen by profiling, on a decent machine this will take about 1ms per chunk
532        // This is to avoid blocking the main thread for hundreds of milliseconds at a time for very big files
533        // If we every change the below code to not query the underlying rope 6 times per token we can bump this up
534        for chunk in server_tokens.tokens().chunks(5000).into_iter() {
535            buffer_tokens.extend(chunk.filter_map(|token| {
536                let start = Unclipped(PointUtf16::new(token.line, token.start));
537                let clipped_start = buffer_snapshot.clip_point_utf16(start, Bias::Left);
538                let start_offset = buffer_snapshot
539                    .as_rope()
540                    .point_utf16_to_offset_utf16(clipped_start);
541                let end_offset = start_offset + OffsetUtf16(token.length as usize);
542
543                let start = buffer_snapshot
544                    .as_rope()
545                    .offset_utf16_to_offset(start_offset);
546                let end = buffer_snapshot.as_rope().offset_utf16_to_offset(end_offset);
547
548                if start == end {
549                    return None;
550                }
551
552                Some(BufferSemanticToken {
553                    range: buffer_snapshot.anchor_before(start)..buffer_snapshot.anchor_after(end),
554                    token_type: token.token_type,
555                    token_modifiers: token.token_modifiers,
556                })
557            }));
558            yield_now().await;
559        }
560
561        res.insert(server_id, buffer_tokens.into());
562        yield_now().await;
563    }
564    res
565}
566
567#[derive(Default, Debug)]
568pub struct SemanticTokensData {
569    pub(super) raw_tokens: RawSemanticTokens,
570    pub(super) latest_invalidation_requests: HashMap<LanguageServerId, Option<usize>>,
571    update: Option<(Global, SemanticTokensTask)>,
572}
573
574/// All the semantic token tokens for a buffer.
575///
576/// This aggregates semantic tokens from multiple language servers in a specific order.
577/// Semantic tokens later in the list will override earlier ones in case of overlap.
578#[derive(Default, Debug, Clone)]
579pub(super) struct RawSemanticTokens {
580    pub servers: HashMap<lsp::LanguageServerId, Arc<ServerSemanticTokens>>,
581}
582
583/// All the semantic tokens for a buffer, from a single language server.
584#[derive(Debug, Clone)]
585pub struct ServerSemanticTokens {
586    /// Each value is:
587    /// data[5*i] - deltaLine: token line number, relative to the start of the previous token
588    /// data[5*i+1] - deltaStart: token start character, relative to the start of the previous token (relative to 0 or the previous token’s start if they are on the same line)
589    /// data[5*i+2] - length: the length of the token.
590    /// data[5*i+3] - tokenType: will be looked up in SemanticTokensLegend.tokenTypes. We currently ask that tokenType < 65536.
591    /// data[5*i+4] - tokenModifiers: each set bit will be looked up in SemanticTokensLegend.tokenModifiers
592    ///
593    /// See https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/ for more.
594    data: Vec<u32>,
595
596    pub(crate) result_id: Option<SharedString>,
597}
598
599pub struct SemanticTokensIter<'a> {
600    prev: Option<(u32, u32)>,
601    data: ChunksExact<'a, u32>,
602}
603
604// A single item from `data`.
605struct SemanticTokenValue {
606    delta_line: u32,
607    delta_start: u32,
608    length: u32,
609    token_type: TokenType,
610    token_modifiers: u32,
611}
612
613/// A semantic token, independent of its position.
614#[derive(Debug, PartialEq, Eq)]
615pub struct SemanticToken {
616    pub line: u32,
617    pub start: u32,
618    pub length: u32,
619    pub token_type: TokenType,
620    pub token_modifiers: u32,
621}
622
623impl ServerSemanticTokens {
624    pub fn from_full(data: Vec<u32>, result_id: Option<SharedString>) -> Self {
625        ServerSemanticTokens { data, result_id }
626    }
627
628    pub(crate) fn apply(&mut self, edits: &[SemanticTokensEdit]) {
629        for edit in edits {
630            let start = edit.start as usize;
631            let end = start + edit.delete_count as usize;
632            self.data.splice(start..end, edit.data.iter().copied());
633        }
634    }
635
636    pub fn tokens(&self) -> SemanticTokensIter<'_> {
637        SemanticTokensIter {
638            prev: None,
639            data: self.data.chunks_exact(5),
640        }
641    }
642}
643
644impl Iterator for SemanticTokensIter<'_> {
645    type Item = SemanticToken;
646
647    fn next(&mut self) -> Option<Self::Item> {
648        let chunk = self.data.next()?;
649        let token = SemanticTokenValue {
650            delta_line: chunk[0],
651            delta_start: chunk[1],
652            length: chunk[2],
653            token_type: TokenType(chunk[3]),
654            token_modifiers: chunk[4],
655        };
656
657        let (line, start) = if let Some((last_line, last_start)) = self.prev {
658            let line = last_line + token.delta_line;
659            let start = if token.delta_line == 0 {
660                last_start + token.delta_start
661            } else {
662                token.delta_start
663            };
664            (line, start)
665        } else {
666            (token.delta_line, token.delta_start)
667        };
668
669        self.prev = Some((line, start));
670
671        Some(SemanticToken {
672            line,
673            start,
674            length: token.length,
675            token_type: token.token_type,
676            token_modifiers: token.token_modifiers,
677        })
678    }
679}
680
681#[cfg(test)]
682mod tests {
683    use super::*;
684    use crate::lsp_command::SemanticTokensEdit;
685    use lsp::SEMANTIC_TOKEN_MODIFIERS;
686
687    fn modifier_names(bits: u32) -> String {
688        if bits == 0 {
689            return "-".to_string();
690        }
691        let names: Vec<&str> = SEMANTIC_TOKEN_MODIFIERS
692            .iter()
693            .enumerate()
694            .filter(|(i, _)| bits & (1 << i) != 0)
695            .map(|(_, m)| m.as_str())
696            .collect();
697
698        // Check for unknown bits
699        let known_bits = (1u32 << SEMANTIC_TOKEN_MODIFIERS.len()) - 1;
700        let unknown = bits & !known_bits;
701
702        if unknown != 0 {
703            let mut result = names.join("+");
704            if !result.is_empty() {
705                result.push('+');
706            }
707            result.push_str(&format!("?0x{:x}", unknown));
708            result
709        } else {
710            names.join("+")
711        }
712    }
713
714    /// Debug tool: parses semantic token JSON from LSP and prints human-readable output.
715    ///
716    /// Usage: Paste JSON into `json_input`, then run:
717    ///   cargo test -p project debug_parse_tokens -- --nocapture --ignored
718    ///
719    /// Accepts either:
720    /// - Full LSP response: `{"jsonrpc":"2.0","id":1,"result":{"data":[...]}}`
721    /// - Just the data array: `[0,0,5,1,0,...]`
722    ///
723    /// For delta responses, paste multiple JSON messages (one per line) and they
724    /// will be applied in sequence.
725    ///
726    /// Token encoding (5 values per token):
727    ///   [deltaLine, deltaStart, length, tokenType, tokenModifiers]
728    #[test]
729    #[ignore] // Run with: cargo test -p project debug_parse_tokens -- --nocapture --ignored
730    fn debug_parse_tokens() {
731        // ============================================================
732        // PASTE YOUR JSON HERE (one message per line for sequences)
733        // Comments starting with // are ignored
734        // ============================================================
735        let json_input = r#"
736// === EXAMPLE 1: Full response (LSP spec example) ===
737// 3 tokens: property at line 2, type at line 2, class at line 5
738{"jsonrpc":"2.0","id":1,"result":{"resultId":"1","data":[2,5,3,9,3,0,5,4,6,0,3,2,7,1,0]}}
739
740// === EXAMPLE 2: Delta response ===
741// User added empty line at start of file, so all tokens shift down by 1 line.
742// This changes first token's deltaLine from 2 to 3 (edit at index 0).
743{"jsonrpc":"2.0","id":2,"result":{"resultId":"2","edits":[{"start":0,"deleteCount":1,"data":[3]}]}}
744
745// === EXAMPLE 3: Another delta ===
746// User added a new token. Insert 5 values at position 5 (after first token).
747// New token: same line as token 1, 2 chars after it ends, len 5, type=function(12), mods=definition(2)
748{"jsonrpc":"2.0","id":3,"result":{"resultId":"3","edits":[{"start":5,"deleteCount":0,"data":[0,2,5,12,2]}]}}
749        "#;
750        // Accepted formats:
751        // - Full response: {"result":{"data":[...]}}
752        // - Delta response: {"result":{"edits":[{"start":N,"deleteCount":N,"data":[...]}]}}
753        // - Just array: [0,0,5,1,0,...]
754
755        // ============================================================
756        // PROCESSING
757        // ============================================================
758        let mut current_data: Vec<u32> = Vec::new();
759        let mut result_id: Option<String> = None;
760
761        for line in json_input.lines() {
762            let line = line.trim();
763            if line.is_empty() || line.starts_with("//") {
764                continue;
765            }
766
767            let parsed: serde_json::Value =
768                serde_json::from_str(line).expect("Failed to parse JSON");
769
770            // Try to extract data from various JSON shapes
771            let (data, edits, new_result_id) = extract_semantic_tokens(&parsed);
772
773            if let Some(new_id) = new_result_id {
774                result_id = Some(new_id);
775            }
776
777            if let Some(full_data) = data {
778                println!("\n{}", "=".repeat(70));
779                println!("FULL RESPONSE (resultId: {:?})", result_id);
780                current_data = full_data;
781            } else if let Some(delta_edits) = edits {
782                println!("\n{}", "=".repeat(70));
783                println!(
784                    "DELTA RESPONSE: {} edit(s) (resultId: {:?})",
785                    delta_edits.len(),
786                    result_id
787                );
788                for (i, edit) in delta_edits.iter().enumerate() {
789                    println!(
790                        "  [{}] start={}, delete={}, insert {} values",
791                        i,
792                        edit.start,
793                        edit.delete_count,
794                        edit.data.len()
795                    );
796                }
797                let mut tokens = ServerSemanticTokens::from_full(current_data.clone(), None);
798                tokens.apply(&delta_edits);
799                current_data = tokens.data;
800            }
801        }
802
803        // Print parsed tokens
804        println!(
805            "\nDATA: {} values = {} tokens",
806            current_data.len(),
807            current_data.len() / 5
808        );
809        println!("\nPARSED TOKENS:");
810        println!("{:-<100}", "");
811        println!(
812            "{:>5} {:>6} {:>4}  {:<15} {}",
813            "LINE", "START", "LEN", "TYPE", "MODIFIERS"
814        );
815        println!("{:-<100}", "");
816
817        let tokens = ServerSemanticTokens::from_full(current_data, None);
818        for token in tokens.tokens() {
819            println!(
820                "{:>5} {:>6} {:>4}  {:<15} {}",
821                token.line,
822                token.start,
823                token.length,
824                token.token_type.0,
825                modifier_names(token.token_modifiers),
826            );
827        }
828        println!("{:-<100}", "");
829        println!("{}\n", "=".repeat(100));
830    }
831
832    fn extract_semantic_tokens(
833        value: &serde_json::Value,
834    ) -> (
835        Option<Vec<u32>>,
836        Option<Vec<SemanticTokensEdit>>,
837        Option<String>,
838    ) {
839        // Try as array directly: [1,2,3,...]
840        if let Some(arr) = value.as_array() {
841            let data: Vec<u32> = arr
842                .iter()
843                .filter_map(|v| v.as_u64().map(|n| n as u32))
844                .collect();
845            return (Some(data), None, None);
846        }
847
848        // Try as LSP response: {"result": {"data": [...]} } or {"result": {"edits": [...]}}
849        let result = value.get("result").unwrap_or(value);
850        let result_id = result
851            .get("resultId")
852            .and_then(|v| v.as_str())
853            .map(String::from);
854
855        // Full response with data
856        if let Some(data_arr) = result.get("data").and_then(|v| v.as_array()) {
857            let data: Vec<u32> = data_arr
858                .iter()
859                .filter_map(|v| v.as_u64().map(|n| n as u32))
860                .collect();
861            return (Some(data), None, result_id);
862        }
863
864        // Delta response with edits
865        if let Some(edits_arr) = result.get("edits").and_then(|v| v.as_array()) {
866            let edits: Vec<SemanticTokensEdit> = edits_arr
867                .iter()
868                .filter_map(|e| {
869                    Some(SemanticTokensEdit {
870                        start: e.get("start")?.as_u64()? as u32,
871                        delete_count: e.get("deleteCount")?.as_u64()? as u32,
872                        data: e
873                            .get("data")
874                            .and_then(|d| d.as_array())
875                            .map(|arr| {
876                                arr.iter()
877                                    .filter_map(|v| v.as_u64().map(|n| n as u32))
878                                    .collect()
879                            })
880                            .unwrap_or_default(),
881                    })
882                })
883                .collect();
884            return (None, Some(edits), result_id);
885        }
886
887        (None, None, result_id)
888    }
889
890    #[test]
891    fn parses_sample_tokens() {
892        // Example from the spec: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocument_semanticTokens
893        let tokens = ServerSemanticTokens::from_full(
894            vec![2, 5, 3, 0, 3, 0, 5, 4, 1, 0, 3, 2, 7, 2, 0],
895            None,
896        )
897        .tokens()
898        .collect::<Vec<SemanticToken>>();
899
900        // The spec uses 1-based line numbers, and 0-based character numbers. This test uses 0-based for both.
901        assert_eq!(
902            tokens,
903            &[
904                SemanticToken {
905                    line: 2,
906                    start: 5,
907                    length: 3,
908                    token_type: TokenType(0),
909                    token_modifiers: 3
910                },
911                SemanticToken {
912                    line: 2,
913                    start: 10,
914                    length: 4,
915                    token_type: TokenType(1),
916                    token_modifiers: 0
917                },
918                SemanticToken {
919                    line: 5,
920                    start: 2,
921                    length: 7,
922                    token_type: TokenType(2),
923                    token_modifiers: 0
924                }
925            ]
926        );
927    }
928
929    #[test]
930    fn applies_delta_edit() {
931        // Example from the spec: https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocument_semanticTokens
932        // After a user types a new empty line at the beginning of the file,
933        // the tokens shift down by one line. The delta edit transforms
934        // [2,5,3,0,3, 0,5,4,1,0, 3,2,7,2,0] into [3,5,3,0,3, 0,5,4,1,0, 3,2,7,2,0]
935        // by replacing the first element (deltaLine of first token) from 2 to 3.
936
937        let mut tokens = ServerSemanticTokens::from_full(
938            vec![2, 5, 3, 0, 3, 0, 5, 4, 1, 0, 3, 2, 7, 2, 0],
939            None,
940        );
941
942        tokens.apply(&[SemanticTokensEdit {
943            start: 0,
944            delete_count: 1,
945            data: vec![3],
946        }]);
947
948        let result = tokens.tokens().collect::<Vec<SemanticToken>>();
949
950        assert_eq!(
951            result,
952            &[
953                SemanticToken {
954                    line: 3,
955                    start: 5,
956                    length: 3,
957                    token_type: TokenType(0),
958                    token_modifiers: 3
959                },
960                SemanticToken {
961                    line: 3,
962                    start: 10,
963                    length: 4,
964                    token_type: TokenType(1),
965                    token_modifiers: 0
966                },
967                SemanticToken {
968                    line: 6,
969                    start: 2,
970                    length: 7,
971                    token_type: TokenType(2),
972                    token_modifiers: 0
973                }
974            ]
975        );
976    }
977}