1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, BracketPair, Grammar, Language, LanguageConfig, LanguageRegistry, PLAIN_TEXT,
   5};
   6use crate::{
   7    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   8    outline::OutlineItem,
   9    CodeLabel, Outline,
  10};
  11use anyhow::{anyhow, Result};
  12use clock::ReplicaId;
  13use futures::FutureExt as _;
  14use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, MutableAppContext, Task};
  15use lazy_static::lazy_static;
  16use parking_lot::Mutex;
  17use similar::{ChangeTag, TextDiff};
  18use smol::future::yield_now;
  19use std::{
  20    any::Any,
  21    cmp::{self, Ordering},
  22    collections::{BTreeMap, HashMap},
  23    ffi::OsString,
  24    future::Future,
  25    iter::{Iterator, Peekable},
  26    ops::{Deref, DerefMut, Range},
  27    path::{Path, PathBuf},
  28    str,
  29    sync::Arc,
  30    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  31    vec,
  32};
  33use sum_tree::TreeMap;
  34use text::operation_queue::OperationQueue;
  35pub use text::{Buffer as TextBuffer, BufferSnapshot as TextBufferSnapshot, Operation as _, *};
  36use theme::SyntaxTheme;
  37use tree_sitter::{InputEdit, QueryCursor, Tree};
  38use util::TryFutureExt as _;
  39
  40#[cfg(any(test, feature = "test-support"))]
  41pub use tree_sitter_rust;
  42
  43pub use lsp::DiagnosticSeverity;
  44
  45lazy_static! {
  46    static ref QUERY_CURSORS: Mutex<Vec<QueryCursor>> = Default::default();
  47}
  48
  49pub struct Buffer {
  50    text: TextBuffer,
  51    file: Option<Box<dyn File>>,
  52    saved_version: clock::Global,
  53    saved_mtime: SystemTime,
  54    language: Option<Arc<Language>>,
  55    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  56    pending_autoindent: Option<Task<()>>,
  57    sync_parse_timeout: Duration,
  58    syntax_tree: Mutex<Option<SyntaxTree>>,
  59    parsing_in_background: bool,
  60    parse_count: usize,
  61    diagnostics: DiagnosticSet,
  62    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  63    selections_update_count: usize,
  64    diagnostics_update_count: usize,
  65    diagnostics_timestamp: clock::Lamport,
  66    file_update_count: usize,
  67    completion_triggers: Vec<String>,
  68    deferred_ops: OperationQueue<Operation>,
  69    indent_size: u32,
  70}
  71
  72pub struct BufferSnapshot {
  73    text: text::BufferSnapshot,
  74    tree: Option<Tree>,
  75    path: Option<Arc<Path>>,
  76    diagnostics: DiagnosticSet,
  77    diagnostics_update_count: usize,
  78    file_update_count: usize,
  79    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  80    selections_update_count: usize,
  81    language: Option<Arc<Language>>,
  82    parse_count: usize,
  83    indent_size: u32,
  84}
  85
  86#[derive(Clone, Debug)]
  87struct SelectionSet {
  88    selections: Arc<[Selection<Anchor>]>,
  89    lamport_timestamp: clock::Lamport,
  90}
  91
  92#[derive(Clone, Debug, PartialEq, Eq)]
  93pub struct GroupId {
  94    source: Arc<str>,
  95    id: usize,
  96}
  97
  98#[derive(Clone, Debug, PartialEq, Eq)]
  99pub struct Diagnostic {
 100    pub code: Option<String>,
 101    pub severity: DiagnosticSeverity,
 102    pub message: String,
 103    pub group_id: usize,
 104    pub is_valid: bool,
 105    pub is_primary: bool,
 106    pub is_disk_based: bool,
 107    pub is_unnecessary: bool,
 108}
 109
 110#[derive(Clone, Debug)]
 111pub struct Completion {
 112    pub old_range: Range<Anchor>,
 113    pub new_text: String,
 114    pub label: CodeLabel,
 115    pub lsp_completion: lsp::CompletionItem,
 116}
 117
 118#[derive(Clone, Debug)]
 119pub struct CodeAction {
 120    pub range: Range<Anchor>,
 121    pub lsp_action: lsp::CodeAction,
 122}
 123
 124#[derive(Clone, Debug, PartialEq, Eq)]
 125pub enum Operation {
 126    Buffer(text::Operation),
 127    UpdateDiagnostics {
 128        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 129        lamport_timestamp: clock::Lamport,
 130    },
 131    UpdateSelections {
 132        selections: Arc<[Selection<Anchor>]>,
 133        lamport_timestamp: clock::Lamport,
 134    },
 135    UpdateCompletionTriggers {
 136        triggers: Vec<String>,
 137        lamport_timestamp: clock::Lamport,
 138    },
 139}
 140
 141#[derive(Clone, Debug, PartialEq, Eq)]
 142pub enum Event {
 143    Operation(Operation),
 144    Edited,
 145    Dirtied,
 146    Saved,
 147    FileHandleChanged,
 148    Reloaded,
 149    Reparsed,
 150    DiagnosticsUpdated,
 151    Closed,
 152}
 153
 154pub trait File {
 155    fn as_local(&self) -> Option<&dyn LocalFile>;
 156
 157    fn is_local(&self) -> bool {
 158        self.as_local().is_some()
 159    }
 160
 161    fn mtime(&self) -> SystemTime;
 162
 163    /// Returns the path of this file relative to the worktree's root directory.
 164    fn path(&self) -> &Arc<Path>;
 165
 166    /// Returns the path of this file relative to the worktree's parent directory (this means it
 167    /// includes the name of the worktree's root folder).
 168    fn full_path(&self, cx: &AppContext) -> PathBuf;
 169
 170    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 171    /// of its worktree, then this method will return the name of the worktree itself.
 172    fn file_name(&self, cx: &AppContext) -> OsString;
 173
 174    fn is_deleted(&self) -> bool;
 175
 176    fn save(
 177        &self,
 178        buffer_id: u64,
 179        text: Rope,
 180        version: clock::Global,
 181        cx: &mut MutableAppContext,
 182    ) -> Task<Result<(clock::Global, SystemTime)>>;
 183
 184    fn as_any(&self) -> &dyn Any;
 185
 186    fn to_proto(&self) -> rpc::proto::File;
 187}
 188
 189pub trait LocalFile: File {
 190    /// Returns the absolute path of this file.
 191    fn abs_path(&self, cx: &AppContext) -> PathBuf;
 192
 193    fn load(&self, cx: &AppContext) -> Task<Result<String>>;
 194
 195    fn buffer_reloaded(
 196        &self,
 197        buffer_id: u64,
 198        version: &clock::Global,
 199        mtime: SystemTime,
 200        cx: &mut MutableAppContext,
 201    );
 202}
 203
 204pub(crate) struct QueryCursorHandle(Option<QueryCursor>);
 205
 206#[derive(Clone)]
 207struct SyntaxTree {
 208    tree: Tree,
 209    version: clock::Global,
 210}
 211
 212#[derive(Clone)]
 213struct AutoindentRequest {
 214    before_edit: BufferSnapshot,
 215    edited: Vec<Anchor>,
 216    inserted: Option<Vec<Range<Anchor>>>,
 217}
 218
 219#[derive(Debug)]
 220struct IndentSuggestion {
 221    basis_row: u32,
 222    indent: bool,
 223}
 224
 225pub(crate) struct TextProvider<'a>(pub(crate) &'a Rope);
 226
 227struct BufferChunkHighlights<'a> {
 228    captures: tree_sitter::QueryCaptures<'a, 'a, TextProvider<'a>>,
 229    next_capture: Option<(tree_sitter::QueryMatch<'a, 'a>, usize)>,
 230    stack: Vec<(usize, HighlightId)>,
 231    highlight_map: HighlightMap,
 232    _query_cursor: QueryCursorHandle,
 233}
 234
 235pub struct BufferChunks<'a> {
 236    range: Range<usize>,
 237    chunks: rope::Chunks<'a>,
 238    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 239    error_depth: usize,
 240    warning_depth: usize,
 241    information_depth: usize,
 242    hint_depth: usize,
 243    unnecessary_depth: usize,
 244    highlights: Option<BufferChunkHighlights<'a>>,
 245}
 246
 247#[derive(Clone, Copy, Debug, Default)]
 248pub struct Chunk<'a> {
 249    pub text: &'a str,
 250    pub syntax_highlight_id: Option<HighlightId>,
 251    pub highlight_style: Option<HighlightStyle>,
 252    pub diagnostic_severity: Option<DiagnosticSeverity>,
 253    pub is_unnecessary: bool,
 254}
 255
 256pub(crate) struct Diff {
 257    base_version: clock::Global,
 258    new_text: Arc<str>,
 259    changes: Vec<(ChangeTag, usize)>,
 260    start_offset: usize,
 261}
 262
 263#[derive(Clone, Copy)]
 264pub(crate) struct DiagnosticEndpoint {
 265    offset: usize,
 266    is_start: bool,
 267    severity: DiagnosticSeverity,
 268    is_unnecessary: bool,
 269}
 270
 271#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 272pub enum CharKind {
 273    Punctuation,
 274    Whitespace,
 275    Word,
 276}
 277
 278impl CharKind {
 279    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 280        if treat_punctuation_as_word && self == CharKind::Punctuation {
 281            CharKind::Word
 282        } else {
 283            self
 284        }
 285    }
 286}
 287
 288impl Buffer {
 289    pub fn new<T: Into<Arc<str>>>(
 290        replica_id: ReplicaId,
 291        base_text: T,
 292        cx: &mut ModelContext<Self>,
 293    ) -> Self {
 294        Self::build(
 295            TextBuffer::new(
 296                replica_id,
 297                cx.model_id() as u64,
 298                History::new(base_text.into()),
 299            ),
 300            None,
 301        )
 302    }
 303
 304    pub fn from_file<T: Into<Arc<str>>>(
 305        replica_id: ReplicaId,
 306        base_text: T,
 307        file: Box<dyn File>,
 308        cx: &mut ModelContext<Self>,
 309    ) -> Self {
 310        Self::build(
 311            TextBuffer::new(
 312                replica_id,
 313                cx.model_id() as u64,
 314                History::new(base_text.into()),
 315            ),
 316            Some(file),
 317        )
 318    }
 319
 320    pub fn from_proto(
 321        replica_id: ReplicaId,
 322        message: proto::BufferState,
 323        file: Option<Box<dyn File>>,
 324        cx: &mut ModelContext<Self>,
 325    ) -> Result<Self> {
 326        let buffer = TextBuffer::new(
 327            replica_id,
 328            message.id,
 329            History::new(Arc::from(message.base_text)),
 330        );
 331        let mut this = Self::build(buffer, file);
 332        let ops = message
 333            .operations
 334            .into_iter()
 335            .map(proto::deserialize_operation)
 336            .collect::<Result<Vec<_>>>()?;
 337        this.apply_ops(ops, cx)?;
 338
 339        for selection_set in message.selections {
 340            let lamport_timestamp = clock::Lamport {
 341                replica_id: selection_set.replica_id as ReplicaId,
 342                value: selection_set.lamport_timestamp,
 343            };
 344            this.remote_selections.insert(
 345                selection_set.replica_id as ReplicaId,
 346                SelectionSet {
 347                    selections: proto::deserialize_selections(selection_set.selections),
 348                    lamport_timestamp,
 349                },
 350            );
 351            this.text.lamport_clock.observe(lamport_timestamp);
 352        }
 353        let snapshot = this.snapshot();
 354        let entries = proto::deserialize_diagnostics(message.diagnostics);
 355        this.apply_diagnostic_update(
 356            DiagnosticSet::from_sorted_entries(entries.iter().cloned(), &snapshot),
 357            clock::Lamport {
 358                replica_id: 0,
 359                value: message.diagnostics_timestamp,
 360            },
 361            cx,
 362        );
 363
 364        this.completion_triggers = message.completion_triggers;
 365
 366        Ok(this)
 367    }
 368
 369    pub fn to_proto(&self) -> proto::BufferState {
 370        let mut operations = self
 371            .text
 372            .history()
 373            .map(|op| proto::serialize_operation(&Operation::Buffer(op.clone())))
 374            .chain(self.deferred_ops.iter().map(proto::serialize_operation))
 375            .collect::<Vec<_>>();
 376        operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 377        proto::BufferState {
 378            id: self.remote_id(),
 379            file: self.file.as_ref().map(|f| f.to_proto()),
 380            base_text: self.base_text().to_string(),
 381            operations,
 382            selections: self
 383                .remote_selections
 384                .iter()
 385                .map(|(replica_id, set)| proto::SelectionSet {
 386                    replica_id: *replica_id as u32,
 387                    selections: proto::serialize_selections(&set.selections),
 388                    lamport_timestamp: set.lamport_timestamp.value,
 389                })
 390                .collect(),
 391            diagnostics: proto::serialize_diagnostics(self.diagnostics.iter()),
 392            diagnostics_timestamp: self.diagnostics_timestamp.value,
 393            completion_triggers: self.completion_triggers.clone(),
 394        }
 395    }
 396
 397    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 398        self.set_language(Some(language), cx);
 399        self
 400    }
 401
 402    fn build(buffer: TextBuffer, file: Option<Box<dyn File>>) -> Self {
 403        let saved_mtime;
 404        if let Some(file) = file.as_ref() {
 405            saved_mtime = file.mtime();
 406        } else {
 407            saved_mtime = UNIX_EPOCH;
 408        }
 409
 410        Self {
 411            saved_mtime,
 412            saved_version: buffer.version(),
 413            text: buffer,
 414            file,
 415            syntax_tree: Mutex::new(None),
 416            parsing_in_background: false,
 417            parse_count: 0,
 418            sync_parse_timeout: Duration::from_millis(1),
 419            autoindent_requests: Default::default(),
 420            pending_autoindent: Default::default(),
 421            language: None,
 422            remote_selections: Default::default(),
 423            selections_update_count: 0,
 424            diagnostics: Default::default(),
 425            diagnostics_update_count: 0,
 426            diagnostics_timestamp: Default::default(),
 427            file_update_count: 0,
 428            completion_triggers: Default::default(),
 429            deferred_ops: OperationQueue::new(),
 430            // TODO: make this configurable
 431            indent_size: 4,
 432        }
 433    }
 434
 435    pub fn snapshot(&self) -> BufferSnapshot {
 436        BufferSnapshot {
 437            text: self.text.snapshot(),
 438            tree: self.syntax_tree(),
 439            path: self.file.as_ref().map(|f| f.path().clone()),
 440            remote_selections: self.remote_selections.clone(),
 441            diagnostics: self.diagnostics.clone(),
 442            diagnostics_update_count: self.diagnostics_update_count,
 443            file_update_count: self.file_update_count,
 444            language: self.language.clone(),
 445            parse_count: self.parse_count,
 446            selections_update_count: self.selections_update_count,
 447            indent_size: self.indent_size,
 448        }
 449    }
 450
 451    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 452        &self.text
 453    }
 454
 455    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 456        self.text.snapshot()
 457    }
 458
 459    pub fn file(&self) -> Option<&dyn File> {
 460        self.file.as_deref()
 461    }
 462
 463    pub fn save(
 464        &mut self,
 465        cx: &mut ModelContext<Self>,
 466    ) -> Task<Result<(clock::Global, SystemTime)>> {
 467        let file = if let Some(file) = self.file.as_ref() {
 468            file
 469        } else {
 470            return Task::ready(Err(anyhow!("buffer has no file")));
 471        };
 472        let text = self.as_rope().clone();
 473        let version = self.version();
 474        let save = file.save(self.remote_id(), text, version, cx.as_mut());
 475        cx.spawn(|this, mut cx| async move {
 476            let (version, mtime) = save.await?;
 477            this.update(&mut cx, |this, cx| {
 478                this.did_save(version.clone(), mtime, None, cx);
 479            });
 480            Ok((version, mtime))
 481        })
 482    }
 483
 484    pub fn saved_version(&self) -> &clock::Global {
 485        &self.saved_version
 486    }
 487
 488    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 489        self.language = language;
 490        self.reparse(cx);
 491    }
 492
 493    pub fn did_save(
 494        &mut self,
 495        version: clock::Global,
 496        mtime: SystemTime,
 497        new_file: Option<Box<dyn File>>,
 498        cx: &mut ModelContext<Self>,
 499    ) {
 500        self.saved_mtime = mtime;
 501        self.saved_version = version;
 502        if let Some(new_file) = new_file {
 503            self.file = Some(new_file);
 504            self.file_update_count += 1;
 505        }
 506        cx.emit(Event::Saved);
 507        cx.notify();
 508    }
 509
 510    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 511        cx.spawn(|this, mut cx| async move {
 512            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 513                let file = this.file.as_ref()?.as_local()?;
 514                Some((file.mtime(), file.load(cx)))
 515            }) {
 516                let new_text = new_text.await?;
 517                let diff = this
 518                    .read_with(&cx, |this, cx| this.diff(new_text.into(), cx))
 519                    .await;
 520                this.update(&mut cx, |this, cx| {
 521                    if let Some(transaction) = this.apply_diff(diff, cx).cloned() {
 522                        this.did_reload(this.version(), new_mtime, cx);
 523                        Ok(Some(transaction))
 524                    } else {
 525                        Ok(None)
 526                    }
 527                })
 528            } else {
 529                Ok(None)
 530            }
 531        })
 532    }
 533
 534    pub fn did_reload(
 535        &mut self,
 536        version: clock::Global,
 537        mtime: SystemTime,
 538        cx: &mut ModelContext<Self>,
 539    ) {
 540        self.saved_mtime = mtime;
 541        self.saved_version = version;
 542        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 543            file.buffer_reloaded(self.remote_id(), &self.saved_version, self.saved_mtime, cx);
 544        }
 545        cx.emit(Event::Reloaded);
 546        cx.notify();
 547    }
 548
 549    pub fn file_updated(
 550        &mut self,
 551        new_file: Box<dyn File>,
 552        cx: &mut ModelContext<Self>,
 553    ) -> Task<()> {
 554        let old_file = if let Some(file) = self.file.as_ref() {
 555            file
 556        } else {
 557            return Task::ready(());
 558        };
 559        let mut file_changed = false;
 560        let mut task = Task::ready(());
 561
 562        if new_file.path() != old_file.path() {
 563            file_changed = true;
 564        }
 565
 566        if new_file.is_deleted() {
 567            if !old_file.is_deleted() {
 568                file_changed = true;
 569                if !self.is_dirty() {
 570                    cx.emit(Event::Dirtied);
 571                }
 572            }
 573        } else {
 574            let new_mtime = new_file.mtime();
 575            if new_mtime != old_file.mtime() {
 576                file_changed = true;
 577
 578                if !self.is_dirty() {
 579                    let reload = self.reload(cx).log_err().map(drop);
 580                    task = cx.foreground().spawn(reload);
 581                }
 582            }
 583        }
 584
 585        if file_changed {
 586            self.file_update_count += 1;
 587            cx.emit(Event::FileHandleChanged);
 588            cx.notify();
 589        }
 590        self.file = Some(new_file);
 591        task
 592    }
 593
 594    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 595        cx.emit(Event::Closed);
 596    }
 597
 598    pub fn language(&self) -> Option<&Arc<Language>> {
 599        self.language.as_ref()
 600    }
 601
 602    pub fn parse_count(&self) -> usize {
 603        self.parse_count
 604    }
 605
 606    pub fn selections_update_count(&self) -> usize {
 607        self.selections_update_count
 608    }
 609
 610    pub fn diagnostics_update_count(&self) -> usize {
 611        self.diagnostics_update_count
 612    }
 613
 614    pub fn file_update_count(&self) -> usize {
 615        self.file_update_count
 616    }
 617
 618    pub(crate) fn syntax_tree(&self) -> Option<Tree> {
 619        if let Some(syntax_tree) = self.syntax_tree.lock().as_mut() {
 620            self.interpolate_tree(syntax_tree);
 621            Some(syntax_tree.tree.clone())
 622        } else {
 623            None
 624        }
 625    }
 626
 627    #[cfg(any(test, feature = "test-support"))]
 628    pub fn is_parsing(&self) -> bool {
 629        self.parsing_in_background
 630    }
 631
 632    #[cfg(test)]
 633    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 634        self.sync_parse_timeout = timeout;
 635    }
 636
 637    fn reparse(&mut self, cx: &mut ModelContext<Self>) -> bool {
 638        if self.parsing_in_background {
 639            return false;
 640        }
 641
 642        if let Some(grammar) = self.grammar().cloned() {
 643            let old_tree = self.syntax_tree();
 644            let text = self.as_rope().clone();
 645            let parsed_version = self.version();
 646            let parse_task = cx.background().spawn({
 647                let grammar = grammar.clone();
 648                async move { grammar.parse_text(&text, old_tree) }
 649            });
 650
 651            match cx
 652                .background()
 653                .block_with_timeout(self.sync_parse_timeout, parse_task)
 654            {
 655                Ok(new_tree) => {
 656                    self.did_finish_parsing(new_tree, parsed_version, cx);
 657                    return true;
 658                }
 659                Err(parse_task) => {
 660                    self.parsing_in_background = true;
 661                    cx.spawn(move |this, mut cx| async move {
 662                        let new_tree = parse_task.await;
 663                        this.update(&mut cx, move |this, cx| {
 664                            let grammar_changed = this
 665                                .grammar()
 666                                .map_or(true, |curr_grammar| !Arc::ptr_eq(&grammar, curr_grammar));
 667                            let parse_again =
 668                                this.version.changed_since(&parsed_version) || grammar_changed;
 669                            this.parsing_in_background = false;
 670                            this.did_finish_parsing(new_tree, parsed_version, cx);
 671
 672                            if parse_again && this.reparse(cx) {
 673                                return;
 674                            }
 675                        });
 676                    })
 677                    .detach();
 678                }
 679            }
 680        }
 681        false
 682    }
 683
 684    fn interpolate_tree(&self, tree: &mut SyntaxTree) {
 685        for edit in self.edits_since::<(usize, Point)>(&tree.version) {
 686            let (bytes, lines) = edit.flatten();
 687            tree.tree.edit(&InputEdit {
 688                start_byte: bytes.new.start,
 689                old_end_byte: bytes.new.start + bytes.old.len(),
 690                new_end_byte: bytes.new.end,
 691                start_position: lines.new.start.to_ts_point(),
 692                old_end_position: (lines.new.start + (lines.old.end - lines.old.start))
 693                    .to_ts_point(),
 694                new_end_position: lines.new.end.to_ts_point(),
 695            });
 696        }
 697        tree.version = self.version();
 698    }
 699
 700    fn did_finish_parsing(
 701        &mut self,
 702        tree: Tree,
 703        version: clock::Global,
 704        cx: &mut ModelContext<Self>,
 705    ) {
 706        self.parse_count += 1;
 707        *self.syntax_tree.lock() = Some(SyntaxTree { tree, version });
 708        self.request_autoindent(cx);
 709        cx.emit(Event::Reparsed);
 710        cx.notify();
 711    }
 712
 713    pub fn update_diagnostics(&mut self, diagnostics: DiagnosticSet, cx: &mut ModelContext<Self>) {
 714        let lamport_timestamp = self.text.lamport_clock.tick();
 715        let op = Operation::UpdateDiagnostics {
 716            diagnostics: diagnostics.iter().cloned().collect(),
 717            lamport_timestamp,
 718        };
 719        self.apply_diagnostic_update(diagnostics, lamport_timestamp, cx);
 720        self.send_operation(op, cx);
 721    }
 722
 723    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 724        if let Some(indent_columns) = self.compute_autoindents() {
 725            let indent_columns = cx.background().spawn(indent_columns);
 726            match cx
 727                .background()
 728                .block_with_timeout(Duration::from_micros(500), indent_columns)
 729            {
 730                Ok(indent_columns) => self.apply_autoindents(indent_columns, cx),
 731                Err(indent_columns) => {
 732                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 733                        let indent_columns = indent_columns.await;
 734                        this.update(&mut cx, |this, cx| {
 735                            this.apply_autoindents(indent_columns, cx);
 736                        });
 737                    }));
 738                }
 739            }
 740        }
 741    }
 742
 743    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, u32>>> {
 744        let max_rows_between_yields = 100;
 745        let snapshot = self.snapshot();
 746        if snapshot.language.is_none()
 747            || snapshot.tree.is_none()
 748            || self.autoindent_requests.is_empty()
 749        {
 750            return None;
 751        }
 752
 753        let autoindent_requests = self.autoindent_requests.clone();
 754        Some(async move {
 755            let mut indent_columns = BTreeMap::new();
 756            for request in autoindent_requests {
 757                let old_to_new_rows = request
 758                    .edited
 759                    .iter()
 760                    .map(|anchor| anchor.summary::<Point>(&request.before_edit).row)
 761                    .zip(
 762                        request
 763                            .edited
 764                            .iter()
 765                            .map(|anchor| anchor.summary::<Point>(&snapshot).row),
 766                    )
 767                    .collect::<BTreeMap<u32, u32>>();
 768
 769                let mut old_suggestions = HashMap::<u32, u32>::default();
 770                let old_edited_ranges =
 771                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 772                for old_edited_range in old_edited_ranges {
 773                    let suggestions = request
 774                        .before_edit
 775                        .suggest_autoindents(old_edited_range.clone())
 776                        .into_iter()
 777                        .flatten();
 778                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 779                        let indentation_basis = old_to_new_rows
 780                            .get(&suggestion.basis_row)
 781                            .and_then(|from_row| old_suggestions.get(from_row).copied())
 782                            .unwrap_or_else(|| {
 783                                request
 784                                    .before_edit
 785                                    .indent_column_for_line(suggestion.basis_row)
 786                            });
 787                        let delta = if suggestion.indent {
 788                            snapshot.indent_size
 789                        } else {
 790                            0
 791                        };
 792                        old_suggestions.insert(
 793                            *old_to_new_rows.get(&old_row).unwrap(),
 794                            indentation_basis + delta,
 795                        );
 796                    }
 797                    yield_now().await;
 798                }
 799
 800                // At this point, old_suggestions contains the suggested indentation for all edited lines with respect to the state of the
 801                // buffer before the edit, but keyed by the row for these lines after the edits were applied.
 802                let new_edited_row_ranges =
 803                    contiguous_ranges(old_to_new_rows.values().copied(), max_rows_between_yields);
 804                for new_edited_row_range in new_edited_row_ranges {
 805                    let suggestions = snapshot
 806                        .suggest_autoindents(new_edited_row_range.clone())
 807                        .into_iter()
 808                        .flatten();
 809                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
 810                        let delta = if suggestion.indent {
 811                            snapshot.indent_size
 812                        } else {
 813                            0
 814                        };
 815                        let new_indentation = indent_columns
 816                            .get(&suggestion.basis_row)
 817                            .copied()
 818                            .unwrap_or_else(|| {
 819                                snapshot.indent_column_for_line(suggestion.basis_row)
 820                            })
 821                            + delta;
 822                        if old_suggestions
 823                            .get(&new_row)
 824                            .map_or(true, |old_indentation| new_indentation != *old_indentation)
 825                        {
 826                            indent_columns.insert(new_row, new_indentation);
 827                        }
 828                    }
 829                    yield_now().await;
 830                }
 831
 832                if let Some(inserted) = request.inserted.as_ref() {
 833                    let inserted_row_ranges = contiguous_ranges(
 834                        inserted
 835                            .iter()
 836                            .map(|range| range.to_point(&snapshot))
 837                            .flat_map(|range| range.start.row..range.end.row + 1),
 838                        max_rows_between_yields,
 839                    );
 840                    for inserted_row_range in inserted_row_ranges {
 841                        let suggestions = snapshot
 842                            .suggest_autoindents(inserted_row_range.clone())
 843                            .into_iter()
 844                            .flatten();
 845                        for (row, suggestion) in inserted_row_range.zip(suggestions) {
 846                            let delta = if suggestion.indent {
 847                                snapshot.indent_size
 848                            } else {
 849                                0
 850                            };
 851                            let new_indentation = indent_columns
 852                                .get(&suggestion.basis_row)
 853                                .copied()
 854                                .unwrap_or_else(|| {
 855                                    snapshot.indent_column_for_line(suggestion.basis_row)
 856                                })
 857                                + delta;
 858                            indent_columns.insert(row, new_indentation);
 859                        }
 860                        yield_now().await;
 861                    }
 862                }
 863            }
 864            indent_columns
 865        })
 866    }
 867
 868    fn apply_autoindents(
 869        &mut self,
 870        indent_columns: BTreeMap<u32, u32>,
 871        cx: &mut ModelContext<Self>,
 872    ) {
 873        self.autoindent_requests.clear();
 874        self.start_transaction();
 875        for (row, indent_column) in &indent_columns {
 876            self.set_indent_column_for_line(*row, *indent_column, cx);
 877        }
 878        self.end_transaction(cx);
 879    }
 880
 881    fn set_indent_column_for_line(&mut self, row: u32, column: u32, cx: &mut ModelContext<Self>) {
 882        let current_column = self.indent_column_for_line(row);
 883        if column > current_column {
 884            let offset = Point::new(row, 0).to_offset(&*self);
 885            self.edit(
 886                [offset..offset],
 887                " ".repeat((column - current_column) as usize),
 888                cx,
 889            );
 890        } else if column < current_column {
 891            self.edit(
 892                [Point::new(row, 0)..Point::new(row, current_column - column)],
 893                "",
 894                cx,
 895            );
 896        }
 897    }
 898
 899    pub(crate) fn diff(&self, new_text: Arc<str>, cx: &AppContext) -> Task<Diff> {
 900        // TODO: it would be nice to not allocate here.
 901        let old_text = self.text();
 902        let base_version = self.version();
 903        cx.background().spawn(async move {
 904            let changes = TextDiff::from_lines(old_text.as_str(), new_text.as_ref())
 905                .iter_all_changes()
 906                .map(|c| (c.tag(), c.value().len()))
 907                .collect::<Vec<_>>();
 908            Diff {
 909                base_version,
 910                new_text,
 911                changes,
 912                start_offset: 0,
 913            }
 914        })
 915    }
 916
 917    pub(crate) fn apply_diff(
 918        &mut self,
 919        diff: Diff,
 920        cx: &mut ModelContext<Self>,
 921    ) -> Option<&Transaction> {
 922        if self.version == diff.base_version {
 923            self.finalize_last_transaction();
 924            self.start_transaction();
 925            let mut offset = diff.start_offset;
 926            for (tag, len) in diff.changes {
 927                let range = offset..(offset + len);
 928                match tag {
 929                    ChangeTag::Equal => offset += len,
 930                    ChangeTag::Delete => {
 931                        self.edit([range], "", cx);
 932                    }
 933                    ChangeTag::Insert => {
 934                        self.edit(
 935                            [offset..offset],
 936                            &diff.new_text
 937                                [range.start - diff.start_offset..range.end - diff.start_offset],
 938                            cx,
 939                        );
 940                        offset += len;
 941                    }
 942                }
 943            }
 944            if self.end_transaction(cx).is_some() {
 945                self.finalize_last_transaction()
 946            } else {
 947                None
 948            }
 949        } else {
 950            None
 951        }
 952    }
 953
 954    pub fn is_dirty(&self) -> bool {
 955        !self.saved_version.observed_all(&self.version)
 956            || self.file.as_ref().map_or(false, |file| file.is_deleted())
 957    }
 958
 959    pub fn has_conflict(&self) -> bool {
 960        !self.saved_version.observed_all(&self.version)
 961            && self
 962                .file
 963                .as_ref()
 964                .map_or(false, |file| file.mtime() > self.saved_mtime)
 965    }
 966
 967    pub fn subscribe(&mut self) -> Subscription {
 968        self.text.subscribe()
 969    }
 970
 971    pub fn start_transaction(&mut self) -> Option<TransactionId> {
 972        self.start_transaction_at(Instant::now())
 973    }
 974
 975    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
 976        self.text.start_transaction_at(now)
 977    }
 978
 979    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
 980        self.end_transaction_at(Instant::now(), cx)
 981    }
 982
 983    pub fn end_transaction_at(
 984        &mut self,
 985        now: Instant,
 986        cx: &mut ModelContext<Self>,
 987    ) -> Option<TransactionId> {
 988        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
 989            let was_dirty = start_version != self.saved_version;
 990            self.did_edit(&start_version, was_dirty, cx);
 991            Some(transaction_id)
 992        } else {
 993            None
 994        }
 995    }
 996
 997    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
 998        self.text.push_transaction(transaction, now);
 999    }
1000
1001    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1002        self.text.finalize_last_transaction()
1003    }
1004
1005    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1006        self.text.forget_transaction(transaction_id);
1007    }
1008
1009    pub fn wait_for_edits(
1010        &mut self,
1011        edit_ids: impl IntoIterator<Item = clock::Local>,
1012    ) -> impl Future<Output = ()> {
1013        self.text.wait_for_edits(edit_ids)
1014    }
1015
1016    pub fn wait_for_anchors<'a>(
1017        &mut self,
1018        anchors: impl IntoIterator<Item = &'a Anchor>,
1019    ) -> impl Future<Output = ()> {
1020        self.text.wait_for_anchors(anchors)
1021    }
1022
1023    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = ()> {
1024        self.text.wait_for_version(version)
1025    }
1026
1027    pub fn set_active_selections(
1028        &mut self,
1029        selections: Arc<[Selection<Anchor>]>,
1030        cx: &mut ModelContext<Self>,
1031    ) {
1032        let lamport_timestamp = self.text.lamport_clock.tick();
1033        self.remote_selections.insert(
1034            self.text.replica_id(),
1035            SelectionSet {
1036                selections: selections.clone(),
1037                lamport_timestamp,
1038            },
1039        );
1040        self.send_operation(
1041            Operation::UpdateSelections {
1042                selections,
1043                lamport_timestamp,
1044            },
1045            cx,
1046        );
1047    }
1048
1049    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1050        self.set_active_selections(Arc::from([]), cx);
1051    }
1052
1053    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1054    where
1055        T: Into<String>,
1056    {
1057        self.edit_internal([0..self.len()], text, false, cx)
1058    }
1059
1060    pub fn edit<I, S, T>(
1061        &mut self,
1062        ranges_iter: I,
1063        new_text: T,
1064        cx: &mut ModelContext<Self>,
1065    ) -> Option<clock::Local>
1066    where
1067        I: IntoIterator<Item = Range<S>>,
1068        S: ToOffset,
1069        T: Into<String>,
1070    {
1071        self.edit_internal(ranges_iter, new_text, false, cx)
1072    }
1073
1074    pub fn edit_with_autoindent<I, S, T>(
1075        &mut self,
1076        ranges_iter: I,
1077        new_text: T,
1078        cx: &mut ModelContext<Self>,
1079    ) -> Option<clock::Local>
1080    where
1081        I: IntoIterator<Item = Range<S>>,
1082        S: ToOffset,
1083        T: Into<String>,
1084    {
1085        self.edit_internal(ranges_iter, new_text, true, cx)
1086    }
1087
1088    pub fn edit_internal<I, S, T>(
1089        &mut self,
1090        ranges_iter: I,
1091        new_text: T,
1092        autoindent: bool,
1093        cx: &mut ModelContext<Self>,
1094    ) -> Option<clock::Local>
1095    where
1096        I: IntoIterator<Item = Range<S>>,
1097        S: ToOffset,
1098        T: Into<String>,
1099    {
1100        let new_text = new_text.into();
1101
1102        // Skip invalid ranges and coalesce contiguous ones.
1103        let mut ranges: Vec<Range<usize>> = Vec::new();
1104        for range in ranges_iter {
1105            let range = range.start.to_offset(self)..range.end.to_offset(self);
1106            if !new_text.is_empty() || !range.is_empty() {
1107                if let Some(prev_range) = ranges.last_mut() {
1108                    if prev_range.end >= range.start {
1109                        prev_range.end = cmp::max(prev_range.end, range.end);
1110                    } else {
1111                        ranges.push(range);
1112                    }
1113                } else {
1114                    ranges.push(range);
1115                }
1116            }
1117        }
1118        if ranges.is_empty() {
1119            return None;
1120        }
1121
1122        self.start_transaction();
1123        self.pending_autoindent.take();
1124        let autoindent_request = if autoindent && self.language.is_some() {
1125            let before_edit = self.snapshot();
1126            let edited = ranges
1127                .iter()
1128                .filter_map(|range| {
1129                    let start = range.start.to_point(self);
1130                    if new_text.starts_with('\n') && start.column == self.line_len(start.row) {
1131                        None
1132                    } else {
1133                        Some(self.anchor_before(range.start))
1134                    }
1135                })
1136                .collect();
1137            Some((before_edit, edited))
1138        } else {
1139            None
1140        };
1141
1142        let first_newline_ix = new_text.find('\n');
1143        let new_text_len = new_text.len();
1144
1145        let edit = self.text.edit(ranges.iter().cloned(), new_text);
1146        let edit_id = edit.local_timestamp();
1147
1148        if let Some((before_edit, edited)) = autoindent_request {
1149            let mut inserted = None;
1150            if let Some(first_newline_ix) = first_newline_ix {
1151                let mut delta = 0isize;
1152                inserted = Some(
1153                    ranges
1154                        .iter()
1155                        .map(|range| {
1156                            let start =
1157                                (delta + range.start as isize) as usize + first_newline_ix + 1;
1158                            let end = (delta + range.start as isize) as usize + new_text_len;
1159                            delta +=
1160                                (range.end as isize - range.start as isize) + new_text_len as isize;
1161                            self.anchor_before(start)..self.anchor_after(end)
1162                        })
1163                        .collect(),
1164                );
1165            }
1166
1167            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1168                before_edit,
1169                edited,
1170                inserted,
1171            }));
1172        }
1173
1174        self.end_transaction(cx);
1175        self.send_operation(Operation::Buffer(edit), cx);
1176        Some(edit_id)
1177    }
1178
1179    fn did_edit(
1180        &mut self,
1181        old_version: &clock::Global,
1182        was_dirty: bool,
1183        cx: &mut ModelContext<Self>,
1184    ) {
1185        if self.edits_since::<usize>(old_version).next().is_none() {
1186            return;
1187        }
1188
1189        self.reparse(cx);
1190
1191        cx.emit(Event::Edited);
1192        if !was_dirty {
1193            cx.emit(Event::Dirtied);
1194        }
1195        cx.notify();
1196    }
1197
1198    fn grammar(&self) -> Option<&Arc<Grammar>> {
1199        self.language.as_ref().and_then(|l| l.grammar.as_ref())
1200    }
1201
1202    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1203        &mut self,
1204        ops: I,
1205        cx: &mut ModelContext<Self>,
1206    ) -> Result<()> {
1207        self.pending_autoindent.take();
1208        let was_dirty = self.is_dirty();
1209        let old_version = self.version.clone();
1210        let mut deferred_ops = Vec::new();
1211        let buffer_ops = ops
1212            .into_iter()
1213            .filter_map(|op| match op {
1214                Operation::Buffer(op) => Some(op),
1215                _ => {
1216                    if self.can_apply_op(&op) {
1217                        self.apply_op(op, cx);
1218                    } else {
1219                        deferred_ops.push(op);
1220                    }
1221                    None
1222                }
1223            })
1224            .collect::<Vec<_>>();
1225        self.text.apply_ops(buffer_ops)?;
1226        self.deferred_ops.insert(deferred_ops);
1227        self.flush_deferred_ops(cx);
1228        self.did_edit(&old_version, was_dirty, cx);
1229        // Notify independently of whether the buffer was edited as the operations could include a
1230        // selection update.
1231        cx.notify();
1232        Ok(())
1233    }
1234
1235    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1236        let mut deferred_ops = Vec::new();
1237        for op in self.deferred_ops.drain().iter().cloned() {
1238            if self.can_apply_op(&op) {
1239                self.apply_op(op, cx);
1240            } else {
1241                deferred_ops.push(op);
1242            }
1243        }
1244        self.deferred_ops.insert(deferred_ops);
1245    }
1246
1247    fn can_apply_op(&self, operation: &Operation) -> bool {
1248        match operation {
1249            Operation::Buffer(_) => {
1250                unreachable!("buffer operations should never be applied at this layer")
1251            }
1252            Operation::UpdateDiagnostics {
1253                diagnostics: diagnostic_set,
1254                ..
1255            } => diagnostic_set.iter().all(|diagnostic| {
1256                self.text.can_resolve(&diagnostic.range.start)
1257                    && self.text.can_resolve(&diagnostic.range.end)
1258            }),
1259            Operation::UpdateSelections { selections, .. } => selections
1260                .iter()
1261                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1262            Operation::UpdateCompletionTriggers { .. } => true,
1263        }
1264    }
1265
1266    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1267        match operation {
1268            Operation::Buffer(_) => {
1269                unreachable!("buffer operations should never be applied at this layer")
1270            }
1271            Operation::UpdateDiagnostics {
1272                diagnostics: diagnostic_set,
1273                lamport_timestamp,
1274            } => {
1275                let snapshot = self.snapshot();
1276                self.apply_diagnostic_update(
1277                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1278                    lamport_timestamp,
1279                    cx,
1280                );
1281            }
1282            Operation::UpdateSelections {
1283                selections,
1284                lamport_timestamp,
1285            } => {
1286                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1287                    if set.lamport_timestamp > lamport_timestamp {
1288                        return;
1289                    }
1290                }
1291
1292                self.remote_selections.insert(
1293                    lamport_timestamp.replica_id,
1294                    SelectionSet {
1295                        selections,
1296                        lamport_timestamp,
1297                    },
1298                );
1299                self.text.lamport_clock.observe(lamport_timestamp);
1300                self.selections_update_count += 1;
1301            }
1302            Operation::UpdateCompletionTriggers {
1303                triggers,
1304                lamport_timestamp,
1305            } => {
1306                self.completion_triggers = triggers;
1307                self.text.lamport_clock.observe(lamport_timestamp);
1308            }
1309        }
1310    }
1311
1312    fn apply_diagnostic_update(
1313        &mut self,
1314        diagnostics: DiagnosticSet,
1315        lamport_timestamp: clock::Lamport,
1316        cx: &mut ModelContext<Self>,
1317    ) {
1318        if lamport_timestamp > self.diagnostics_timestamp {
1319            self.diagnostics = diagnostics;
1320            self.diagnostics_timestamp = lamport_timestamp;
1321            self.diagnostics_update_count += 1;
1322            self.text.lamport_clock.observe(lamport_timestamp);
1323            cx.notify();
1324            cx.emit(Event::DiagnosticsUpdated);
1325        }
1326    }
1327
1328    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1329        cx.emit(Event::Operation(operation));
1330    }
1331
1332    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1333        self.remote_selections.remove(&replica_id);
1334        cx.notify();
1335    }
1336
1337    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1338        let was_dirty = self.is_dirty();
1339        let old_version = self.version.clone();
1340
1341        if let Some((transaction_id, operation)) = self.text.undo() {
1342            self.send_operation(Operation::Buffer(operation), cx);
1343            self.did_edit(&old_version, was_dirty, cx);
1344            Some(transaction_id)
1345        } else {
1346            None
1347        }
1348    }
1349
1350    pub fn undo_to_transaction(
1351        &mut self,
1352        transaction_id: TransactionId,
1353        cx: &mut ModelContext<Self>,
1354    ) -> bool {
1355        let was_dirty = self.is_dirty();
1356        let old_version = self.version.clone();
1357
1358        let operations = self.text.undo_to_transaction(transaction_id);
1359        let undone = !operations.is_empty();
1360        for operation in operations {
1361            self.send_operation(Operation::Buffer(operation), cx);
1362        }
1363        if undone {
1364            self.did_edit(&old_version, was_dirty, cx)
1365        }
1366        undone
1367    }
1368
1369    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1370        let was_dirty = self.is_dirty();
1371        let old_version = self.version.clone();
1372
1373        if let Some((transaction_id, operation)) = self.text.redo() {
1374            self.send_operation(Operation::Buffer(operation), cx);
1375            self.did_edit(&old_version, was_dirty, cx);
1376            Some(transaction_id)
1377        } else {
1378            None
1379        }
1380    }
1381
1382    pub fn redo_to_transaction(
1383        &mut self,
1384        transaction_id: TransactionId,
1385        cx: &mut ModelContext<Self>,
1386    ) -> bool {
1387        let was_dirty = self.is_dirty();
1388        let old_version = self.version.clone();
1389
1390        let operations = self.text.redo_to_transaction(transaction_id);
1391        let redone = !operations.is_empty();
1392        for operation in operations {
1393            self.send_operation(Operation::Buffer(operation), cx);
1394        }
1395        if redone {
1396            self.did_edit(&old_version, was_dirty, cx)
1397        }
1398        redone
1399    }
1400
1401    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1402        self.completion_triggers = triggers.clone();
1403        let lamport_timestamp = self.text.lamport_clock.tick();
1404        self.send_operation(
1405            Operation::UpdateCompletionTriggers {
1406                triggers,
1407                lamport_timestamp,
1408            },
1409            cx,
1410        );
1411        cx.notify();
1412    }
1413
1414    pub fn completion_triggers(&self) -> &[String] {
1415        &self.completion_triggers
1416    }
1417}
1418
1419#[cfg(any(test, feature = "test-support"))]
1420impl Buffer {
1421    pub fn set_group_interval(&mut self, group_interval: Duration) {
1422        self.text.set_group_interval(group_interval);
1423    }
1424
1425    pub fn randomly_edit<T>(
1426        &mut self,
1427        rng: &mut T,
1428        old_range_count: usize,
1429        cx: &mut ModelContext<Self>,
1430    ) where
1431        T: rand::Rng,
1432    {
1433        let mut old_ranges: Vec<Range<usize>> = Vec::new();
1434        for _ in 0..old_range_count {
1435            let last_end = old_ranges.last().map_or(0, |last_range| last_range.end + 1);
1436            if last_end > self.len() {
1437                break;
1438            }
1439            old_ranges.push(self.text.random_byte_range(last_end, rng));
1440        }
1441        let new_text_len = rng.gen_range(0..10);
1442        let new_text: String = crate::random_char_iter::RandomCharIter::new(&mut *rng)
1443            .take(new_text_len)
1444            .collect();
1445        log::info!(
1446            "mutating buffer {} at {:?}: {:?}",
1447            self.replica_id(),
1448            old_ranges,
1449            new_text
1450        );
1451        self.edit(old_ranges.iter().cloned(), new_text.as_str(), cx);
1452    }
1453
1454    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1455        let was_dirty = self.is_dirty();
1456        let old_version = self.version.clone();
1457
1458        let ops = self.text.randomly_undo_redo(rng);
1459        if !ops.is_empty() {
1460            for op in ops {
1461                self.send_operation(Operation::Buffer(op), cx);
1462                self.did_edit(&old_version, was_dirty, cx);
1463            }
1464        }
1465    }
1466}
1467
1468impl Entity for Buffer {
1469    type Event = Event;
1470}
1471
1472impl Deref for Buffer {
1473    type Target = TextBuffer;
1474
1475    fn deref(&self) -> &Self::Target {
1476        &self.text
1477    }
1478}
1479
1480impl BufferSnapshot {
1481    fn suggest_autoindents<'a>(
1482        &'a self,
1483        row_range: Range<u32>,
1484    ) -> Option<impl Iterator<Item = IndentSuggestion> + 'a> {
1485        let mut query_cursor = QueryCursorHandle::new();
1486        if let Some((grammar, tree)) = self.grammar().zip(self.tree.as_ref()) {
1487            let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1488
1489            // Get the "indentation ranges" that intersect this row range.
1490            let indent_capture_ix = grammar.indents_query.capture_index_for_name("indent");
1491            let end_capture_ix = grammar.indents_query.capture_index_for_name("end");
1492            query_cursor.set_point_range(
1493                Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0).to_ts_point()
1494                    ..Point::new(row_range.end, 0).to_ts_point(),
1495            );
1496            let mut indentation_ranges = Vec::<(Range<Point>, &'static str)>::new();
1497            for mat in query_cursor.matches(
1498                &grammar.indents_query,
1499                tree.root_node(),
1500                TextProvider(self.as_rope()),
1501            ) {
1502                let mut node_kind = "";
1503                let mut start: Option<Point> = None;
1504                let mut end: Option<Point> = None;
1505                for capture in mat.captures {
1506                    if Some(capture.index) == indent_capture_ix {
1507                        node_kind = capture.node.kind();
1508                        start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1509                        end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1510                    } else if Some(capture.index) == end_capture_ix {
1511                        end = Some(Point::from_ts_point(capture.node.start_position().into()));
1512                    }
1513                }
1514
1515                if let Some((start, end)) = start.zip(end) {
1516                    if start.row == end.row {
1517                        continue;
1518                    }
1519
1520                    let range = start..end;
1521                    match indentation_ranges.binary_search_by_key(&range.start, |r| r.0.start) {
1522                        Err(ix) => indentation_ranges.insert(ix, (range, node_kind)),
1523                        Ok(ix) => {
1524                            let prev_range = &mut indentation_ranges[ix];
1525                            prev_range.0.end = prev_range.0.end.max(range.end);
1526                        }
1527                    }
1528                }
1529            }
1530
1531            let mut prev_row = prev_non_blank_row.unwrap_or(0);
1532            Some(row_range.map(move |row| {
1533                let row_start = Point::new(row, self.indent_column_for_line(row));
1534
1535                let mut indent_from_prev_row = false;
1536                let mut outdent_to_row = u32::MAX;
1537                for (range, _node_kind) in &indentation_ranges {
1538                    if range.start.row >= row {
1539                        break;
1540                    }
1541
1542                    if range.start.row == prev_row && range.end > row_start {
1543                        indent_from_prev_row = true;
1544                    }
1545                    if range.end.row >= prev_row && range.end <= row_start {
1546                        outdent_to_row = outdent_to_row.min(range.start.row);
1547                    }
1548                }
1549
1550                let suggestion = if outdent_to_row == prev_row {
1551                    IndentSuggestion {
1552                        basis_row: prev_row,
1553                        indent: false,
1554                    }
1555                } else if indent_from_prev_row {
1556                    IndentSuggestion {
1557                        basis_row: prev_row,
1558                        indent: true,
1559                    }
1560                } else if outdent_to_row < prev_row {
1561                    IndentSuggestion {
1562                        basis_row: outdent_to_row,
1563                        indent: false,
1564                    }
1565                } else {
1566                    IndentSuggestion {
1567                        basis_row: prev_row,
1568                        indent: false,
1569                    }
1570                };
1571
1572                prev_row = row;
1573                suggestion
1574            }))
1575        } else {
1576            None
1577        }
1578    }
1579
1580    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
1581        while row > 0 {
1582            row -= 1;
1583            if !self.is_line_blank(row) {
1584                return Some(row);
1585            }
1586        }
1587        None
1588    }
1589
1590    pub fn chunks<'a, T: ToOffset>(
1591        &'a self,
1592        range: Range<T>,
1593        language_aware: bool,
1594    ) -> BufferChunks<'a> {
1595        let range = range.start.to_offset(self)..range.end.to_offset(self);
1596
1597        let mut tree = None;
1598        let mut diagnostic_endpoints = Vec::new();
1599        if language_aware {
1600            tree = self.tree.as_ref();
1601            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
1602                diagnostic_endpoints.push(DiagnosticEndpoint {
1603                    offset: entry.range.start,
1604                    is_start: true,
1605                    severity: entry.diagnostic.severity,
1606                    is_unnecessary: entry.diagnostic.is_unnecessary,
1607                });
1608                diagnostic_endpoints.push(DiagnosticEndpoint {
1609                    offset: entry.range.end,
1610                    is_start: false,
1611                    severity: entry.diagnostic.severity,
1612                    is_unnecessary: entry.diagnostic.is_unnecessary,
1613                });
1614            }
1615            diagnostic_endpoints
1616                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
1617        }
1618
1619        BufferChunks::new(
1620            self.text.as_rope(),
1621            range,
1622            tree,
1623            self.grammar(),
1624            diagnostic_endpoints,
1625        )
1626    }
1627
1628    pub fn language(&self) -> Option<&Arc<Language>> {
1629        self.language.as_ref()
1630    }
1631
1632    fn grammar(&self) -> Option<&Arc<Grammar>> {
1633        self.language
1634            .as_ref()
1635            .and_then(|language| language.grammar.as_ref())
1636    }
1637
1638    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
1639        let tree = self.tree.as_ref()?;
1640        let range = range.start.to_offset(self)..range.end.to_offset(self);
1641        let mut cursor = tree.root_node().walk();
1642
1643        // Descend to the first leaf that touches the start of the range,
1644        // and if the range is non-empty, extends beyond the start.
1645        while cursor.goto_first_child_for_byte(range.start).is_some() {
1646            if !range.is_empty() && cursor.node().end_byte() == range.start {
1647                cursor.goto_next_sibling();
1648            }
1649        }
1650
1651        // Ascend to the smallest ancestor that strictly contains the range.
1652        loop {
1653            let node_range = cursor.node().byte_range();
1654            if node_range.start <= range.start
1655                && node_range.end >= range.end
1656                && node_range.len() > range.len()
1657            {
1658                break;
1659            }
1660            if !cursor.goto_parent() {
1661                break;
1662            }
1663        }
1664
1665        let left_node = cursor.node();
1666
1667        // For an empty range, try to find another node immediately to the right of the range.
1668        if left_node.end_byte() == range.start {
1669            let mut right_node = None;
1670            while !cursor.goto_next_sibling() {
1671                if !cursor.goto_parent() {
1672                    break;
1673                }
1674            }
1675
1676            while cursor.node().start_byte() == range.start {
1677                right_node = Some(cursor.node());
1678                if !cursor.goto_first_child() {
1679                    break;
1680                }
1681            }
1682
1683            // If there is a candidate node on both sides of the (empty) range, then
1684            // decide between the two by favoring a named node over an anonymous token.
1685            // If both nodes are the same in that regard, favor the right one.
1686            if let Some(right_node) = right_node {
1687                if right_node.is_named() || !left_node.is_named() {
1688                    return Some(right_node.byte_range());
1689                }
1690            }
1691        }
1692
1693        Some(left_node.byte_range())
1694    }
1695
1696    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
1697        self.outline_items_containing(0..self.len(), theme)
1698            .map(Outline::new)
1699    }
1700
1701    pub fn symbols_containing<T: ToOffset>(
1702        &self,
1703        position: T,
1704        theme: Option<&SyntaxTheme>,
1705    ) -> Option<Vec<OutlineItem<Anchor>>> {
1706        let position = position.to_offset(&self);
1707        let mut items =
1708            self.outline_items_containing(position.saturating_sub(1)..position + 1, theme)?;
1709        let mut prev_depth = None;
1710        items.retain(|item| {
1711            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
1712            prev_depth = Some(item.depth);
1713            result
1714        });
1715        Some(items)
1716    }
1717
1718    fn outline_items_containing(
1719        &self,
1720        range: Range<usize>,
1721        theme: Option<&SyntaxTheme>,
1722    ) -> Option<Vec<OutlineItem<Anchor>>> {
1723        let tree = self.tree.as_ref()?;
1724        let grammar = self
1725            .language
1726            .as_ref()
1727            .and_then(|language| language.grammar.as_ref())?;
1728
1729        let mut cursor = QueryCursorHandle::new();
1730        cursor.set_byte_range(range);
1731        let matches = cursor.matches(
1732            &grammar.outline_query,
1733            tree.root_node(),
1734            TextProvider(self.as_rope()),
1735        );
1736
1737        let mut chunks = self.chunks(0..self.len(), true);
1738
1739        let item_capture_ix = grammar.outline_query.capture_index_for_name("item")?;
1740        let name_capture_ix = grammar.outline_query.capture_index_for_name("name")?;
1741        let context_capture_ix = grammar
1742            .outline_query
1743            .capture_index_for_name("context")
1744            .unwrap_or(u32::MAX);
1745
1746        let mut stack = Vec::<Range<usize>>::new();
1747        let items = matches
1748            .filter_map(|mat| {
1749                let item_node = mat.nodes_for_capture_index(item_capture_ix).next()?;
1750                let range = item_node.start_byte()..item_node.end_byte();
1751                let mut text = String::new();
1752                let mut name_ranges = Vec::new();
1753                let mut highlight_ranges = Vec::new();
1754
1755                for capture in mat.captures {
1756                    let node_is_name;
1757                    if capture.index == name_capture_ix {
1758                        node_is_name = true;
1759                    } else if capture.index == context_capture_ix {
1760                        node_is_name = false;
1761                    } else {
1762                        continue;
1763                    }
1764
1765                    let range = capture.node.start_byte()..capture.node.end_byte();
1766                    if !text.is_empty() {
1767                        text.push(' ');
1768                    }
1769                    if node_is_name {
1770                        let mut start = text.len();
1771                        let end = start + range.len();
1772
1773                        // When multiple names are captured, then the matcheable text
1774                        // includes the whitespace in between the names.
1775                        if !name_ranges.is_empty() {
1776                            start -= 1;
1777                        }
1778
1779                        name_ranges.push(start..end);
1780                    }
1781
1782                    let mut offset = range.start;
1783                    chunks.seek(offset);
1784                    while let Some(mut chunk) = chunks.next() {
1785                        if chunk.text.len() > range.end - offset {
1786                            chunk.text = &chunk.text[0..(range.end - offset)];
1787                            offset = range.end;
1788                        } else {
1789                            offset += chunk.text.len();
1790                        }
1791                        let style = chunk
1792                            .syntax_highlight_id
1793                            .zip(theme)
1794                            .and_then(|(highlight, theme)| highlight.style(theme));
1795                        if let Some(style) = style {
1796                            let start = text.len();
1797                            let end = start + chunk.text.len();
1798                            highlight_ranges.push((start..end, style));
1799                        }
1800                        text.push_str(chunk.text);
1801                        if offset >= range.end {
1802                            break;
1803                        }
1804                    }
1805                }
1806
1807                while stack.last().map_or(false, |prev_range| {
1808                    !prev_range.contains(&range.start) || !prev_range.contains(&range.end)
1809                }) {
1810                    stack.pop();
1811                }
1812                stack.push(range.clone());
1813
1814                Some(OutlineItem {
1815                    depth: stack.len() - 1,
1816                    range: self.anchor_after(range.start)..self.anchor_before(range.end),
1817                    text,
1818                    highlight_ranges,
1819                    name_ranges,
1820                })
1821            })
1822            .collect::<Vec<_>>();
1823        Some(items)
1824    }
1825
1826    pub fn enclosing_bracket_ranges<T: ToOffset>(
1827        &self,
1828        range: Range<T>,
1829    ) -> Option<(Range<usize>, Range<usize>)> {
1830        let (grammar, tree) = self.grammar().zip(self.tree.as_ref())?;
1831        let open_capture_ix = grammar.brackets_query.capture_index_for_name("open")?;
1832        let close_capture_ix = grammar.brackets_query.capture_index_for_name("close")?;
1833
1834        // Find bracket pairs that *inclusively* contain the given range.
1835        let range = range.start.to_offset(self).saturating_sub(1)..range.end.to_offset(self) + 1;
1836        let mut cursor = QueryCursorHandle::new();
1837        let matches = cursor.set_byte_range(range).matches(
1838            &grammar.brackets_query,
1839            tree.root_node(),
1840            TextProvider(self.as_rope()),
1841        );
1842
1843        // Get the ranges of the innermost pair of brackets.
1844        matches
1845            .filter_map(|mat| {
1846                let open = mat.nodes_for_capture_index(open_capture_ix).next()?;
1847                let close = mat.nodes_for_capture_index(close_capture_ix).next()?;
1848                Some((open.byte_range(), close.byte_range()))
1849            })
1850            .min_by_key(|(open_range, close_range)| close_range.end - open_range.start)
1851    }
1852
1853    pub fn remote_selections_in_range<'a>(
1854        &'a self,
1855        range: Range<Anchor>,
1856    ) -> impl 'a + Iterator<Item = (ReplicaId, impl 'a + Iterator<Item = &'a Selection<Anchor>>)>
1857    {
1858        self.remote_selections
1859            .iter()
1860            .filter(|(replica_id, set)| {
1861                **replica_id != self.text.replica_id() && !set.selections.is_empty()
1862            })
1863            .map(move |(replica_id, set)| {
1864                let start_ix = match set.selections.binary_search_by(|probe| {
1865                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
1866                }) {
1867                    Ok(ix) | Err(ix) => ix,
1868                };
1869                let end_ix = match set.selections.binary_search_by(|probe| {
1870                    probe.start.cmp(&range.end, self).then(Ordering::Less)
1871                }) {
1872                    Ok(ix) | Err(ix) => ix,
1873                };
1874
1875                (*replica_id, set.selections[start_ix..end_ix].iter())
1876            })
1877    }
1878
1879    pub fn diagnostics_in_range<'a, T, O>(
1880        &'a self,
1881        search_range: Range<T>,
1882        reversed: bool,
1883    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1884    where
1885        T: 'a + Clone + ToOffset,
1886        O: 'a + FromAnchor,
1887    {
1888        self.diagnostics
1889            .range(search_range.clone(), self, true, reversed)
1890    }
1891
1892    pub fn diagnostic_groups(&self) -> Vec<DiagnosticGroup<Anchor>> {
1893        let mut groups = Vec::new();
1894        self.diagnostics.groups(&mut groups, self);
1895        groups
1896    }
1897
1898    pub fn diagnostic_group<'a, O>(
1899        &'a self,
1900        group_id: usize,
1901    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1902    where
1903        O: 'a + FromAnchor,
1904    {
1905        self.diagnostics.group(group_id, self)
1906    }
1907
1908    pub fn diagnostics_update_count(&self) -> usize {
1909        self.diagnostics_update_count
1910    }
1911
1912    pub fn parse_count(&self) -> usize {
1913        self.parse_count
1914    }
1915
1916    pub fn selections_update_count(&self) -> usize {
1917        self.selections_update_count
1918    }
1919
1920    pub fn path(&self) -> Option<&Arc<Path>> {
1921        self.path.as_ref()
1922    }
1923
1924    pub fn file_update_count(&self) -> usize {
1925        self.file_update_count
1926    }
1927
1928    pub fn indent_size(&self) -> u32 {
1929        self.indent_size
1930    }
1931}
1932
1933impl Clone for BufferSnapshot {
1934    fn clone(&self) -> Self {
1935        Self {
1936            text: self.text.clone(),
1937            tree: self.tree.clone(),
1938            path: self.path.clone(),
1939            remote_selections: self.remote_selections.clone(),
1940            diagnostics: self.diagnostics.clone(),
1941            selections_update_count: self.selections_update_count,
1942            diagnostics_update_count: self.diagnostics_update_count,
1943            file_update_count: self.file_update_count,
1944            language: self.language.clone(),
1945            parse_count: self.parse_count,
1946            indent_size: self.indent_size,
1947        }
1948    }
1949}
1950
1951impl Deref for BufferSnapshot {
1952    type Target = text::BufferSnapshot;
1953
1954    fn deref(&self) -> &Self::Target {
1955        &self.text
1956    }
1957}
1958
1959impl<'a> tree_sitter::TextProvider<'a> for TextProvider<'a> {
1960    type I = ByteChunks<'a>;
1961
1962    fn text(&mut self, node: tree_sitter::Node) -> Self::I {
1963        ByteChunks(self.0.chunks_in_range(node.byte_range()))
1964    }
1965}
1966
1967pub(crate) struct ByteChunks<'a>(rope::Chunks<'a>);
1968
1969impl<'a> Iterator for ByteChunks<'a> {
1970    type Item = &'a [u8];
1971
1972    fn next(&mut self) -> Option<Self::Item> {
1973        self.0.next().map(str::as_bytes)
1974    }
1975}
1976
1977unsafe impl<'a> Send for BufferChunks<'a> {}
1978
1979impl<'a> BufferChunks<'a> {
1980    pub(crate) fn new(
1981        text: &'a Rope,
1982        range: Range<usize>,
1983        tree: Option<&'a Tree>,
1984        grammar: Option<&'a Arc<Grammar>>,
1985        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
1986    ) -> Self {
1987        let mut highlights = None;
1988        if let Some((grammar, tree)) = grammar.zip(tree) {
1989            let mut query_cursor = QueryCursorHandle::new();
1990
1991            // TODO - add a Tree-sitter API to remove the need for this.
1992            let cursor = unsafe {
1993                std::mem::transmute::<_, &'static mut QueryCursor>(query_cursor.deref_mut())
1994            };
1995            let captures = cursor.set_byte_range(range.clone()).captures(
1996                &grammar.highlights_query,
1997                tree.root_node(),
1998                TextProvider(text),
1999            );
2000            highlights = Some(BufferChunkHighlights {
2001                captures,
2002                next_capture: None,
2003                stack: Default::default(),
2004                highlight_map: grammar.highlight_map(),
2005                _query_cursor: query_cursor,
2006            })
2007        }
2008
2009        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2010        let chunks = text.chunks_in_range(range.clone());
2011
2012        BufferChunks {
2013            range,
2014            chunks,
2015            diagnostic_endpoints,
2016            error_depth: 0,
2017            warning_depth: 0,
2018            information_depth: 0,
2019            hint_depth: 0,
2020            unnecessary_depth: 0,
2021            highlights,
2022        }
2023    }
2024
2025    pub fn seek(&mut self, offset: usize) {
2026        self.range.start = offset;
2027        self.chunks.seek(self.range.start);
2028        if let Some(highlights) = self.highlights.as_mut() {
2029            highlights
2030                .stack
2031                .retain(|(end_offset, _)| *end_offset > offset);
2032            if let Some((mat, capture_ix)) = &highlights.next_capture {
2033                let capture = mat.captures[*capture_ix as usize];
2034                if offset >= capture.node.start_byte() {
2035                    let next_capture_end = capture.node.end_byte();
2036                    if offset < next_capture_end {
2037                        highlights.stack.push((
2038                            next_capture_end,
2039                            highlights.highlight_map.get(capture.index),
2040                        ));
2041                    }
2042                    highlights.next_capture.take();
2043                }
2044            }
2045            highlights.captures.set_byte_range(self.range.clone());
2046        }
2047    }
2048
2049    pub fn offset(&self) -> usize {
2050        self.range.start
2051    }
2052
2053    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2054        let depth = match endpoint.severity {
2055            DiagnosticSeverity::ERROR => &mut self.error_depth,
2056            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2057            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2058            DiagnosticSeverity::HINT => &mut self.hint_depth,
2059            _ => return,
2060        };
2061        if endpoint.is_start {
2062            *depth += 1;
2063        } else {
2064            *depth -= 1;
2065        }
2066
2067        if endpoint.is_unnecessary {
2068            if endpoint.is_start {
2069                self.unnecessary_depth += 1;
2070            } else {
2071                self.unnecessary_depth -= 1;
2072            }
2073        }
2074    }
2075
2076    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2077        if self.error_depth > 0 {
2078            Some(DiagnosticSeverity::ERROR)
2079        } else if self.warning_depth > 0 {
2080            Some(DiagnosticSeverity::WARNING)
2081        } else if self.information_depth > 0 {
2082            Some(DiagnosticSeverity::INFORMATION)
2083        } else if self.hint_depth > 0 {
2084            Some(DiagnosticSeverity::HINT)
2085        } else {
2086            None
2087        }
2088    }
2089
2090    fn current_code_is_unnecessary(&self) -> bool {
2091        self.unnecessary_depth > 0
2092    }
2093}
2094
2095impl<'a> Iterator for BufferChunks<'a> {
2096    type Item = Chunk<'a>;
2097
2098    fn next(&mut self) -> Option<Self::Item> {
2099        let mut next_capture_start = usize::MAX;
2100        let mut next_diagnostic_endpoint = usize::MAX;
2101
2102        if let Some(highlights) = self.highlights.as_mut() {
2103            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2104                if *parent_capture_end <= self.range.start {
2105                    highlights.stack.pop();
2106                } else {
2107                    break;
2108                }
2109            }
2110
2111            if highlights.next_capture.is_none() {
2112                highlights.next_capture = highlights.captures.next();
2113            }
2114
2115            while let Some((mat, capture_ix)) = highlights.next_capture.as_ref() {
2116                let capture = mat.captures[*capture_ix as usize];
2117                if self.range.start < capture.node.start_byte() {
2118                    next_capture_start = capture.node.start_byte();
2119                    break;
2120                } else {
2121                    let highlight_id = highlights.highlight_map.get(capture.index);
2122                    highlights
2123                        .stack
2124                        .push((capture.node.end_byte(), highlight_id));
2125                    highlights.next_capture = highlights.captures.next();
2126                }
2127            }
2128        }
2129
2130        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2131            if endpoint.offset <= self.range.start {
2132                self.update_diagnostic_depths(endpoint);
2133                self.diagnostic_endpoints.next();
2134            } else {
2135                next_diagnostic_endpoint = endpoint.offset;
2136                break;
2137            }
2138        }
2139
2140        if let Some(chunk) = self.chunks.peek() {
2141            let chunk_start = self.range.start;
2142            let mut chunk_end = (self.chunks.offset() + chunk.len())
2143                .min(next_capture_start)
2144                .min(next_diagnostic_endpoint);
2145            let mut highlight_id = None;
2146            if let Some(highlights) = self.highlights.as_ref() {
2147                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2148                    chunk_end = chunk_end.min(*parent_capture_end);
2149                    highlight_id = Some(*parent_highlight_id);
2150                }
2151            }
2152
2153            let slice =
2154                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2155            self.range.start = chunk_end;
2156            if self.range.start == self.chunks.offset() + chunk.len() {
2157                self.chunks.next().unwrap();
2158            }
2159
2160            Some(Chunk {
2161                text: slice,
2162                syntax_highlight_id: highlight_id,
2163                highlight_style: None,
2164                diagnostic_severity: self.current_diagnostic_severity(),
2165                is_unnecessary: self.current_code_is_unnecessary(),
2166            })
2167        } else {
2168            None
2169        }
2170    }
2171}
2172
2173impl QueryCursorHandle {
2174    pub(crate) fn new() -> Self {
2175        QueryCursorHandle(Some(
2176            QUERY_CURSORS
2177                .lock()
2178                .pop()
2179                .unwrap_or_else(|| QueryCursor::new()),
2180        ))
2181    }
2182}
2183
2184impl Deref for QueryCursorHandle {
2185    type Target = QueryCursor;
2186
2187    fn deref(&self) -> &Self::Target {
2188        self.0.as_ref().unwrap()
2189    }
2190}
2191
2192impl DerefMut for QueryCursorHandle {
2193    fn deref_mut(&mut self) -> &mut Self::Target {
2194        self.0.as_mut().unwrap()
2195    }
2196}
2197
2198impl Drop for QueryCursorHandle {
2199    fn drop(&mut self) {
2200        let mut cursor = self.0.take().unwrap();
2201        cursor.set_byte_range(0..usize::MAX);
2202        cursor.set_point_range(Point::zero().to_ts_point()..Point::MAX.to_ts_point());
2203        QUERY_CURSORS.lock().push(cursor)
2204    }
2205}
2206
2207trait ToTreeSitterPoint {
2208    fn to_ts_point(self) -> tree_sitter::Point;
2209    fn from_ts_point(point: tree_sitter::Point) -> Self;
2210}
2211
2212impl ToTreeSitterPoint for Point {
2213    fn to_ts_point(self) -> tree_sitter::Point {
2214        tree_sitter::Point::new(self.row as usize, self.column as usize)
2215    }
2216
2217    fn from_ts_point(point: tree_sitter::Point) -> Self {
2218        Point::new(point.row as u32, point.column as u32)
2219    }
2220}
2221
2222impl operation_queue::Operation for Operation {
2223    fn lamport_timestamp(&self) -> clock::Lamport {
2224        match self {
2225            Operation::Buffer(_) => {
2226                unreachable!("buffer operations should never be deferred at this layer")
2227            }
2228            Operation::UpdateDiagnostics {
2229                lamport_timestamp, ..
2230            }
2231            | Operation::UpdateSelections {
2232                lamport_timestamp, ..
2233            }
2234            | Operation::UpdateCompletionTriggers {
2235                lamport_timestamp, ..
2236            } => *lamport_timestamp,
2237        }
2238    }
2239}
2240
2241impl Default for Diagnostic {
2242    fn default() -> Self {
2243        Self {
2244            code: Default::default(),
2245            severity: DiagnosticSeverity::ERROR,
2246            message: Default::default(),
2247            group_id: Default::default(),
2248            is_primary: Default::default(),
2249            is_valid: true,
2250            is_disk_based: false,
2251            is_unnecessary: false,
2252        }
2253    }
2254}
2255
2256impl Completion {
2257    pub fn sort_key(&self) -> (usize, &str) {
2258        let kind_key = match self.lsp_completion.kind {
2259            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2260            _ => 1,
2261        };
2262        (kind_key, &self.label.text[self.label.filter_range.clone()])
2263    }
2264
2265    pub fn is_snippet(&self) -> bool {
2266        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2267    }
2268}
2269
2270pub fn contiguous_ranges(
2271    values: impl Iterator<Item = u32>,
2272    max_len: usize,
2273) -> impl Iterator<Item = Range<u32>> {
2274    let mut values = values.into_iter();
2275    let mut current_range: Option<Range<u32>> = None;
2276    std::iter::from_fn(move || loop {
2277        if let Some(value) = values.next() {
2278            if let Some(range) = &mut current_range {
2279                if value == range.end && range.len() < max_len {
2280                    range.end += 1;
2281                    continue;
2282                }
2283            }
2284
2285            let prev_range = current_range.clone();
2286            current_range = Some(value..(value + 1));
2287            if prev_range.is_some() {
2288                return prev_range;
2289            }
2290        } else {
2291            return current_range.take();
2292        }
2293    })
2294}
2295
2296pub fn char_kind(c: char) -> CharKind {
2297    if c.is_whitespace() {
2298        CharKind::Whitespace
2299    } else if c.is_alphanumeric() || c == '_' {
2300        CharKind::Word
2301    } else {
2302        CharKind::Punctuation
2303    }
2304}