1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, BracketPair, Grammar, Language, LanguageConfig, LanguageRegistry, LanguageServerConfig,
   5    PLAIN_TEXT,
   6};
   7use crate::{
   8    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   9    range_from_lsp,
  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 lsp::LanguageServer;
  17use parking_lot::Mutex;
  18use postage::{prelude::Stream, sink::Sink, watch};
  19use similar::{ChangeTag, TextDiff};
  20use smol::future::yield_now;
  21use std::{
  22    any::Any,
  23    cell::RefCell,
  24    cmp::{self, Ordering},
  25    collections::{BTreeMap, HashMap},
  26    ffi::OsString,
  27    future::Future,
  28    iter::{Iterator, Peekable},
  29    ops::{Deref, DerefMut, Range, Sub},
  30    path::{Path, PathBuf},
  31    str,
  32    sync::Arc,
  33    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  34    vec,
  35};
  36use sum_tree::TreeMap;
  37use text::{operation_queue::OperationQueue, rope::TextDimension};
  38pub use text::{Buffer as TextBuffer, Operation as _, *};
  39use theme::SyntaxTheme;
  40use tree_sitter::{InputEdit, Parser, QueryCursor, Tree};
  41use util::{post_inc, TryFutureExt as _};
  42
  43#[cfg(any(test, feature = "test-support"))]
  44pub use tree_sitter_rust;
  45
  46pub use lsp::DiagnosticSeverity;
  47
  48thread_local! {
  49    static PARSER: RefCell<Parser> = RefCell::new(Parser::new());
  50}
  51
  52lazy_static! {
  53    static ref QUERY_CURSORS: Mutex<Vec<QueryCursor>> = Default::default();
  54}
  55
  56// TODO - Make this configurable
  57const INDENT_SIZE: u32 = 4;
  58
  59pub struct Buffer {
  60    text: TextBuffer,
  61    file: Option<Box<dyn File>>,
  62    saved_version: clock::Global,
  63    saved_mtime: SystemTime,
  64    language: Option<Arc<Language>>,
  65    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  66    pending_autoindent: Option<Task<()>>,
  67    sync_parse_timeout: Duration,
  68    syntax_tree: Mutex<Option<SyntaxTree>>,
  69    parsing_in_background: bool,
  70    parse_count: usize,
  71    diagnostics: DiagnosticSet,
  72    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  73    selections_update_count: usize,
  74    diagnostics_update_count: usize,
  75    language_server: Option<LanguageServerState>,
  76    deferred_ops: OperationQueue<Operation>,
  77    #[cfg(test)]
  78    pub(crate) operations: Vec<Operation>,
  79}
  80
  81pub struct BufferSnapshot {
  82    text: text::BufferSnapshot,
  83    tree: Option<Tree>,
  84    diagnostics: DiagnosticSet,
  85    diagnostics_update_count: usize,
  86    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  87    selections_update_count: usize,
  88    is_parsing: bool,
  89    language: Option<Arc<Language>>,
  90    parse_count: usize,
  91}
  92
  93#[derive(Clone, Debug)]
  94struct SelectionSet {
  95    selections: Arc<[Selection<Anchor>]>,
  96    lamport_timestamp: clock::Lamport,
  97}
  98
  99#[derive(Clone, Debug, PartialEq, Eq)]
 100pub struct GroupId {
 101    source: Arc<str>,
 102    id: usize,
 103}
 104
 105#[derive(Clone, Debug, PartialEq, Eq)]
 106pub struct Diagnostic {
 107    pub code: Option<String>,
 108    pub severity: DiagnosticSeverity,
 109    pub message: String,
 110    pub group_id: usize,
 111    pub is_valid: bool,
 112    pub is_primary: bool,
 113    pub is_disk_based: bool,
 114}
 115
 116struct LanguageServerState {
 117    server: Arc<LanguageServer>,
 118    latest_snapshot: watch::Sender<Option<LanguageServerSnapshot>>,
 119    pending_snapshots: BTreeMap<usize, LanguageServerSnapshot>,
 120    next_version: usize,
 121    _maintain_server: Task<Option<()>>,
 122}
 123
 124#[derive(Clone)]
 125struct LanguageServerSnapshot {
 126    buffer_snapshot: text::BufferSnapshot,
 127    version: usize,
 128    path: Arc<Path>,
 129}
 130
 131#[derive(Clone, Debug)]
 132pub enum Operation {
 133    Buffer(text::Operation),
 134    UpdateDiagnostics {
 135        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 136        lamport_timestamp: clock::Lamport,
 137    },
 138    UpdateSelections {
 139        replica_id: ReplicaId,
 140        selections: Arc<[Selection<Anchor>]>,
 141        lamport_timestamp: clock::Lamport,
 142    },
 143}
 144
 145#[derive(Clone, Debug, Eq, PartialEq)]
 146pub enum Event {
 147    Edited,
 148    Dirtied,
 149    Saved,
 150    FileHandleChanged,
 151    Reloaded,
 152    Reparsed,
 153    DiagnosticsUpdated,
 154    Closed,
 155}
 156
 157pub trait File {
 158    fn mtime(&self) -> SystemTime;
 159
 160    /// Returns the path of this file relative to the worktree's root directory.
 161    fn path(&self) -> &Arc<Path>;
 162
 163    /// Returns the absolute path of this file.
 164    fn abs_path(&self) -> Option<PathBuf>;
 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) -> 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) -> Option<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 load_local(&self, cx: &AppContext) -> Option<Task<Result<String>>>;
 185
 186    fn format_remote(&self, buffer_id: u64, cx: &mut MutableAppContext)
 187        -> Option<Task<Result<()>>>;
 188
 189    fn buffer_updated(&self, buffer_id: u64, operation: Operation, cx: &mut MutableAppContext);
 190
 191    fn buffer_removed(&self, buffer_id: u64, cx: &mut MutableAppContext);
 192
 193    fn as_any(&self) -> &dyn Any;
 194}
 195
 196struct QueryCursorHandle(Option<QueryCursor>);
 197
 198#[derive(Clone)]
 199struct SyntaxTree {
 200    tree: Tree,
 201    version: clock::Global,
 202}
 203
 204#[derive(Clone)]
 205struct AutoindentRequest {
 206    before_edit: BufferSnapshot,
 207    edited: Vec<Anchor>,
 208    inserted: Option<Vec<Range<Anchor>>>,
 209}
 210
 211#[derive(Debug)]
 212struct IndentSuggestion {
 213    basis_row: u32,
 214    indent: bool,
 215}
 216
 217struct TextProvider<'a>(&'a Rope);
 218
 219struct BufferChunkHighlights<'a> {
 220    captures: tree_sitter::QueryCaptures<'a, 'a, TextProvider<'a>>,
 221    next_capture: Option<(tree_sitter::QueryMatch<'a, 'a>, usize)>,
 222    stack: Vec<(usize, HighlightId)>,
 223    highlight_map: HighlightMap,
 224    theme: &'a SyntaxTheme,
 225    _query_cursor: QueryCursorHandle,
 226}
 227
 228pub struct BufferChunks<'a> {
 229    range: Range<usize>,
 230    chunks: rope::Chunks<'a>,
 231    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 232    error_depth: usize,
 233    warning_depth: usize,
 234    information_depth: usize,
 235    hint_depth: usize,
 236    highlights: Option<BufferChunkHighlights<'a>>,
 237}
 238
 239#[derive(Clone, Copy, Debug, Default)]
 240pub struct Chunk<'a> {
 241    pub text: &'a str,
 242    pub highlight_style: Option<HighlightStyle>,
 243    pub diagnostic: Option<DiagnosticSeverity>,
 244}
 245
 246pub(crate) struct Diff {
 247    base_version: clock::Global,
 248    new_text: Arc<str>,
 249    changes: Vec<(ChangeTag, usize)>,
 250}
 251
 252#[derive(Clone, Copy)]
 253struct DiagnosticEndpoint {
 254    offset: usize,
 255    is_start: bool,
 256    severity: DiagnosticSeverity,
 257}
 258
 259impl Buffer {
 260    pub fn new<T: Into<Arc<str>>>(
 261        replica_id: ReplicaId,
 262        base_text: T,
 263        cx: &mut ModelContext<Self>,
 264    ) -> Self {
 265        Self::build(
 266            TextBuffer::new(
 267                replica_id,
 268                cx.model_id() as u64,
 269                History::new(base_text.into()),
 270            ),
 271            None,
 272        )
 273    }
 274
 275    pub fn from_file<T: Into<Arc<str>>>(
 276        replica_id: ReplicaId,
 277        base_text: T,
 278        file: Box<dyn File>,
 279        cx: &mut ModelContext<Self>,
 280    ) -> Self {
 281        Self::build(
 282            TextBuffer::new(
 283                replica_id,
 284                cx.model_id() as u64,
 285                History::new(base_text.into()),
 286            ),
 287            Some(file),
 288        )
 289    }
 290
 291    pub fn from_proto(
 292        replica_id: ReplicaId,
 293        message: proto::Buffer,
 294        file: Option<Box<dyn File>>,
 295        cx: &mut ModelContext<Self>,
 296    ) -> Result<Self> {
 297        let fragments_len = message.fragments.len();
 298        let buffer = TextBuffer::from_parts(
 299            replica_id,
 300            message.id,
 301            &message.visible_text,
 302            &message.deleted_text,
 303            message
 304                .undo_map
 305                .into_iter()
 306                .map(proto::deserialize_undo_map_entry),
 307            message
 308                .fragments
 309                .into_iter()
 310                .enumerate()
 311                .map(|(i, fragment)| {
 312                    proto::deserialize_buffer_fragment(fragment, i, fragments_len)
 313                }),
 314            message.lamport_timestamp,
 315            From::from(message.version),
 316        );
 317        let mut this = Self::build(buffer, file);
 318        for selection_set in message.selections {
 319            this.remote_selections.insert(
 320                selection_set.replica_id as ReplicaId,
 321                SelectionSet {
 322                    selections: proto::deserialize_selections(selection_set.selections),
 323                    lamport_timestamp: clock::Lamport {
 324                        replica_id: selection_set.replica_id as ReplicaId,
 325                        value: selection_set.lamport_timestamp,
 326                    },
 327                },
 328            );
 329        }
 330        let snapshot = this.snapshot();
 331        let entries = proto::deserialize_diagnostics(message.diagnostics);
 332        this.apply_diagnostic_update(
 333            DiagnosticSet::from_sorted_entries(entries.into_iter().cloned(), &snapshot),
 334            cx,
 335        );
 336
 337        let deferred_ops = message
 338            .deferred_operations
 339            .into_iter()
 340            .map(proto::deserialize_operation)
 341            .collect::<Result<Vec<_>>>()?;
 342        this.apply_ops(deferred_ops, cx)?;
 343
 344        Ok(this)
 345    }
 346
 347    pub fn to_proto(&self) -> proto::Buffer {
 348        proto::Buffer {
 349            id: self.remote_id(),
 350            visible_text: self.text.text(),
 351            deleted_text: self.text.deleted_text(),
 352            undo_map: self
 353                .text
 354                .undo_history()
 355                .map(proto::serialize_undo_map_entry)
 356                .collect(),
 357            version: From::from(&self.version),
 358            lamport_timestamp: self.lamport_clock.value,
 359            fragments: self
 360                .text
 361                .fragments()
 362                .map(proto::serialize_buffer_fragment)
 363                .collect(),
 364            selections: self
 365                .remote_selections
 366                .iter()
 367                .map(|(replica_id, set)| proto::SelectionSet {
 368                    replica_id: *replica_id as u32,
 369                    selections: proto::serialize_selections(&set.selections),
 370                    lamport_timestamp: set.lamport_timestamp.value,
 371                })
 372                .collect(),
 373            diagnostics: proto::serialize_diagnostics(self.diagnostics.iter()),
 374            deferred_operations: self
 375                .deferred_ops
 376                .iter()
 377                .map(proto::serialize_operation)
 378                .chain(
 379                    self.text
 380                        .deferred_ops()
 381                        .map(|op| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 382                )
 383                .collect(),
 384        }
 385    }
 386
 387    pub fn with_language(
 388        mut self,
 389        language: Option<Arc<Language>>,
 390        language_server: Option<Arc<LanguageServer>>,
 391        cx: &mut ModelContext<Self>,
 392    ) -> Self {
 393        self.set_language(language, language_server, cx);
 394        self
 395    }
 396
 397    fn build(buffer: TextBuffer, file: Option<Box<dyn File>>) -> Self {
 398        let saved_mtime;
 399        if let Some(file) = file.as_ref() {
 400            saved_mtime = file.mtime();
 401        } else {
 402            saved_mtime = UNIX_EPOCH;
 403        }
 404
 405        Self {
 406            saved_mtime,
 407            saved_version: buffer.version(),
 408            text: buffer,
 409            file,
 410            syntax_tree: Mutex::new(None),
 411            parsing_in_background: false,
 412            parse_count: 0,
 413            sync_parse_timeout: Duration::from_millis(1),
 414            autoindent_requests: Default::default(),
 415            pending_autoindent: Default::default(),
 416            language: None,
 417            remote_selections: Default::default(),
 418            selections_update_count: 0,
 419            diagnostics: Default::default(),
 420            diagnostics_update_count: 0,
 421            language_server: None,
 422            deferred_ops: OperationQueue::new(),
 423            #[cfg(test)]
 424            operations: Default::default(),
 425        }
 426    }
 427
 428    pub fn snapshot(&self) -> BufferSnapshot {
 429        BufferSnapshot {
 430            text: self.text.snapshot(),
 431            tree: self.syntax_tree(),
 432            remote_selections: self.remote_selections.clone(),
 433            diagnostics: self.diagnostics.clone(),
 434            diagnostics_update_count: self.diagnostics_update_count,
 435            is_parsing: self.parsing_in_background,
 436            language: self.language.clone(),
 437            parse_count: self.parse_count,
 438            selections_update_count: self.selections_update_count,
 439        }
 440    }
 441
 442    pub fn file(&self) -> Option<&dyn File> {
 443        self.file.as_deref()
 444    }
 445
 446    pub fn format(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<()>> {
 447        let file = if let Some(file) = self.file.as_ref() {
 448            file
 449        } else {
 450            return Task::ready(Err(anyhow!("buffer has no file")));
 451        };
 452
 453        if let Some(LanguageServerState { server, .. }) = self.language_server.as_ref() {
 454            let server = server.clone();
 455            let abs_path = file.abs_path().unwrap();
 456            let version = self.version();
 457            cx.spawn(|this, mut cx| async move {
 458                let edits = server
 459                    .request::<lsp::request::Formatting>(lsp::DocumentFormattingParams {
 460                        text_document: lsp::TextDocumentIdentifier::new(
 461                            lsp::Url::from_file_path(&abs_path).unwrap(),
 462                        ),
 463                        options: Default::default(),
 464                        work_done_progress_params: Default::default(),
 465                    })
 466                    .await?;
 467
 468                if let Some(edits) = edits {
 469                    this.update(&mut cx, |this, cx| {
 470                        if this.version == version {
 471                            for edit in &edits {
 472                                let range = range_from_lsp(edit.range);
 473                                if this.clip_point_utf16(range.start, Bias::Left) != range.start
 474                                    || this.clip_point_utf16(range.end, Bias::Left) != range.end
 475                                {
 476                                    return Err(anyhow!(
 477                                        "invalid formatting edits received from language server"
 478                                    ));
 479                                }
 480                            }
 481
 482                            for edit in edits.into_iter().rev() {
 483                                this.edit([range_from_lsp(edit.range)], edit.new_text, cx);
 484                            }
 485                            Ok(())
 486                        } else {
 487                            Err(anyhow!("buffer edited since starting to format"))
 488                        }
 489                    })
 490                } else {
 491                    Ok(())
 492                }
 493            })
 494        } else {
 495            let format = file.format_remote(self.remote_id(), cx.as_mut());
 496            cx.spawn(|_, _| async move {
 497                if let Some(format) = format {
 498                    format.await?;
 499                }
 500                Ok(())
 501            })
 502        }
 503    }
 504
 505    pub fn save(
 506        &mut self,
 507        cx: &mut ModelContext<Self>,
 508    ) -> Result<Task<Result<(clock::Global, SystemTime)>>> {
 509        let file = self
 510            .file
 511            .as_ref()
 512            .ok_or_else(|| anyhow!("buffer has no file"))?;
 513        let text = self.as_rope().clone();
 514        let version = self.version();
 515        let save = file.save(self.remote_id(), text, version, cx.as_mut());
 516        Ok(cx.spawn(|this, mut cx| async move {
 517            let (version, mtime) = save.await?;
 518            this.update(&mut cx, |this, cx| {
 519                this.did_save(version.clone(), mtime, None, cx);
 520            });
 521            Ok((version, mtime))
 522        }))
 523    }
 524
 525    pub fn set_language(
 526        &mut self,
 527        language: Option<Arc<Language>>,
 528        language_server: Option<Arc<lsp::LanguageServer>>,
 529        cx: &mut ModelContext<Self>,
 530    ) {
 531        self.language = language;
 532        self.language_server = if let Some(server) = language_server {
 533            let (latest_snapshot_tx, mut latest_snapshot_rx) = watch::channel();
 534            Some(LanguageServerState {
 535                latest_snapshot: latest_snapshot_tx,
 536                pending_snapshots: Default::default(),
 537                next_version: 0,
 538                server: server.clone(),
 539                _maintain_server: cx.background().spawn(
 540                    async move {
 541                        let mut prev_snapshot: Option<LanguageServerSnapshot> = None;
 542                        while let Some(snapshot) = latest_snapshot_rx.recv().await {
 543                            if let Some(snapshot) = snapshot {
 544                                let uri = lsp::Url::from_file_path(&snapshot.path).unwrap();
 545                                if let Some(prev_snapshot) = prev_snapshot {
 546                                    let changes = lsp::DidChangeTextDocumentParams {
 547                                        text_document: lsp::VersionedTextDocumentIdentifier::new(
 548                                            uri,
 549                                            snapshot.version as i32,
 550                                        ),
 551                                        content_changes: snapshot
 552                                            .buffer_snapshot
 553                                            .edits_since::<(PointUtf16, usize)>(
 554                                                prev_snapshot.buffer_snapshot.version(),
 555                                            )
 556                                            .map(|edit| {
 557                                                let edit_start = edit.new.start.0;
 558                                                let edit_end = edit_start
 559                                                    + (edit.old.end.0 - edit.old.start.0);
 560                                                let new_text = snapshot
 561                                                    .buffer_snapshot
 562                                                    .text_for_range(
 563                                                        edit.new.start.1..edit.new.end.1,
 564                                                    )
 565                                                    .collect();
 566                                                lsp::TextDocumentContentChangeEvent {
 567                                                    range: Some(lsp::Range::new(
 568                                                        lsp::Position::new(
 569                                                            edit_start.row,
 570                                                            edit_start.column,
 571                                                        ),
 572                                                        lsp::Position::new(
 573                                                            edit_end.row,
 574                                                            edit_end.column,
 575                                                        ),
 576                                                    )),
 577                                                    range_length: None,
 578                                                    text: new_text,
 579                                                }
 580                                            })
 581                                            .collect(),
 582                                    };
 583                                    server
 584                                        .notify::<lsp::notification::DidChangeTextDocument>(changes)
 585                                        .await?;
 586                                } else {
 587                                    server
 588                                        .notify::<lsp::notification::DidOpenTextDocument>(
 589                                            lsp::DidOpenTextDocumentParams {
 590                                                text_document: lsp::TextDocumentItem::new(
 591                                                    uri,
 592                                                    Default::default(),
 593                                                    snapshot.version as i32,
 594                                                    snapshot.buffer_snapshot.text().to_string(),
 595                                                ),
 596                                            },
 597                                        )
 598                                        .await?;
 599                                }
 600
 601                                prev_snapshot = Some(snapshot);
 602                            }
 603                        }
 604                        Ok(())
 605                    }
 606                    .log_err(),
 607                ),
 608            })
 609        } else {
 610            None
 611        };
 612
 613        self.reparse(cx);
 614        self.update_language_server();
 615    }
 616
 617    pub fn did_save(
 618        &mut self,
 619        version: clock::Global,
 620        mtime: SystemTime,
 621        new_file: Option<Box<dyn File>>,
 622        cx: &mut ModelContext<Self>,
 623    ) {
 624        self.saved_mtime = mtime;
 625        self.saved_version = version;
 626        if let Some(new_file) = new_file {
 627            self.file = Some(new_file);
 628        }
 629        if let Some(state) = &self.language_server {
 630            cx.background()
 631                .spawn(
 632                    state
 633                        .server
 634                        .notify::<lsp::notification::DidSaveTextDocument>(
 635                            lsp::DidSaveTextDocumentParams {
 636                                text_document: lsp::TextDocumentIdentifier {
 637                                    uri: lsp::Url::from_file_path(
 638                                        self.file.as_ref().unwrap().abs_path().unwrap(),
 639                                    )
 640                                    .unwrap(),
 641                                },
 642                                text: None,
 643                            },
 644                        ),
 645                )
 646                .detach()
 647        }
 648        cx.emit(Event::Saved);
 649    }
 650
 651    pub fn file_updated(
 652        &mut self,
 653        new_file: Box<dyn File>,
 654        cx: &mut ModelContext<Self>,
 655    ) -> Option<Task<()>> {
 656        let old_file = self.file.as_ref()?;
 657        let mut file_changed = false;
 658        let mut task = None;
 659
 660        if new_file.path() != old_file.path() {
 661            file_changed = true;
 662        }
 663
 664        if new_file.is_deleted() {
 665            if !old_file.is_deleted() {
 666                file_changed = true;
 667                if !self.is_dirty() {
 668                    cx.emit(Event::Dirtied);
 669                }
 670            }
 671        } else {
 672            let new_mtime = new_file.mtime();
 673            if new_mtime != old_file.mtime() {
 674                file_changed = true;
 675
 676                if !self.is_dirty() {
 677                    task = Some(cx.spawn(|this, mut cx| {
 678                        async move {
 679                            let new_text = this.read_with(&cx, |this, cx| {
 680                                this.file.as_ref().and_then(|file| file.load_local(cx))
 681                            });
 682                            if let Some(new_text) = new_text {
 683                                let new_text = new_text.await?;
 684                                let diff = this
 685                                    .read_with(&cx, |this, cx| this.diff(new_text.into(), cx))
 686                                    .await;
 687                                this.update(&mut cx, |this, cx| {
 688                                    if this.apply_diff(diff, cx) {
 689                                        this.saved_version = this.version();
 690                                        this.saved_mtime = new_mtime;
 691                                        cx.emit(Event::Reloaded);
 692                                    }
 693                                });
 694                            }
 695                            Ok(())
 696                        }
 697                        .log_err()
 698                        .map(drop)
 699                    }));
 700                }
 701            }
 702        }
 703
 704        if file_changed {
 705            cx.emit(Event::FileHandleChanged);
 706        }
 707        self.file = Some(new_file);
 708        task
 709    }
 710
 711    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 712        cx.emit(Event::Closed);
 713    }
 714
 715    pub fn language(&self) -> Option<&Arc<Language>> {
 716        self.language.as_ref()
 717    }
 718
 719    pub fn parse_count(&self) -> usize {
 720        self.parse_count
 721    }
 722
 723    pub fn selections_update_count(&self) -> usize {
 724        self.selections_update_count
 725    }
 726
 727    pub fn diagnostics_update_count(&self) -> usize {
 728        self.diagnostics_update_count
 729    }
 730
 731    pub(crate) fn syntax_tree(&self) -> Option<Tree> {
 732        if let Some(syntax_tree) = self.syntax_tree.lock().as_mut() {
 733            self.interpolate_tree(syntax_tree);
 734            Some(syntax_tree.tree.clone())
 735        } else {
 736            None
 737        }
 738    }
 739
 740    #[cfg(any(test, feature = "test-support"))]
 741    pub fn is_parsing(&self) -> bool {
 742        self.parsing_in_background
 743    }
 744
 745    #[cfg(test)]
 746    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 747        self.sync_parse_timeout = timeout;
 748    }
 749
 750    fn reparse(&mut self, cx: &mut ModelContext<Self>) -> bool {
 751        if self.parsing_in_background {
 752            return false;
 753        }
 754
 755        if let Some(grammar) = self.grammar().cloned() {
 756            let old_tree = self.syntax_tree();
 757            let text = self.as_rope().clone();
 758            let parsed_version = self.version();
 759            let parse_task = cx.background().spawn({
 760                let grammar = grammar.clone();
 761                async move { Self::parse_text(&text, old_tree, &grammar) }
 762            });
 763
 764            match cx
 765                .background()
 766                .block_with_timeout(self.sync_parse_timeout, parse_task)
 767            {
 768                Ok(new_tree) => {
 769                    self.did_finish_parsing(new_tree, parsed_version, cx);
 770                    return true;
 771                }
 772                Err(parse_task) => {
 773                    self.parsing_in_background = true;
 774                    cx.spawn(move |this, mut cx| async move {
 775                        let new_tree = parse_task.await;
 776                        this.update(&mut cx, move |this, cx| {
 777                            let grammar_changed = this
 778                                .grammar()
 779                                .map_or(true, |curr_grammar| !Arc::ptr_eq(&grammar, curr_grammar));
 780                            let parse_again =
 781                                this.version.changed_since(&parsed_version) || grammar_changed;
 782                            this.parsing_in_background = false;
 783                            this.did_finish_parsing(new_tree, parsed_version, cx);
 784
 785                            if parse_again && this.reparse(cx) {
 786                                return;
 787                            }
 788                        });
 789                    })
 790                    .detach();
 791                }
 792            }
 793        }
 794        false
 795    }
 796
 797    fn parse_text(text: &Rope, old_tree: Option<Tree>, grammar: &Grammar) -> Tree {
 798        PARSER.with(|parser| {
 799            let mut parser = parser.borrow_mut();
 800            parser
 801                .set_language(grammar.ts_language)
 802                .expect("incompatible grammar");
 803            let mut chunks = text.chunks_in_range(0..text.len());
 804            let tree = parser
 805                .parse_with(
 806                    &mut move |offset, _| {
 807                        chunks.seek(offset);
 808                        chunks.next().unwrap_or("").as_bytes()
 809                    },
 810                    old_tree.as_ref(),
 811                )
 812                .unwrap();
 813            tree
 814        })
 815    }
 816
 817    fn interpolate_tree(&self, tree: &mut SyntaxTree) {
 818        for edit in self.edits_since::<(usize, Point)>(&tree.version) {
 819            let (bytes, lines) = edit.flatten();
 820            tree.tree.edit(&InputEdit {
 821                start_byte: bytes.new.start,
 822                old_end_byte: bytes.new.start + bytes.old.len(),
 823                new_end_byte: bytes.new.end,
 824                start_position: lines.new.start.to_ts_point(),
 825                old_end_position: (lines.new.start + (lines.old.end - lines.old.start))
 826                    .to_ts_point(),
 827                new_end_position: lines.new.end.to_ts_point(),
 828            });
 829        }
 830        tree.version = self.version();
 831    }
 832
 833    fn did_finish_parsing(
 834        &mut self,
 835        tree: Tree,
 836        version: clock::Global,
 837        cx: &mut ModelContext<Self>,
 838    ) {
 839        self.parse_count += 1;
 840        *self.syntax_tree.lock() = Some(SyntaxTree { tree, version });
 841        self.request_autoindent(cx);
 842        cx.emit(Event::Reparsed);
 843        cx.notify();
 844    }
 845
 846    pub fn update_diagnostics<T>(
 847        &mut self,
 848        version: Option<i32>,
 849        mut diagnostics: Vec<DiagnosticEntry<T>>,
 850        cx: &mut ModelContext<Self>,
 851    ) -> Result<Operation>
 852    where
 853        T: Copy + Ord + TextDimension + Sub<Output = T> + Clip + ToPoint,
 854    {
 855        fn compare_diagnostics(a: &Diagnostic, b: &Diagnostic) -> Ordering {
 856            Ordering::Equal
 857                .then_with(|| b.is_primary.cmp(&a.is_primary))
 858                .then_with(|| a.is_disk_based.cmp(&b.is_disk_based))
 859                .then_with(|| a.severity.cmp(&b.severity))
 860                .then_with(|| a.message.cmp(&b.message))
 861        }
 862
 863        let version = version.map(|version| version as usize);
 864        let content = if let Some(version) = version {
 865            let language_server = self.language_server.as_mut().unwrap();
 866            language_server
 867                .pending_snapshots
 868                .retain(|&v, _| v >= version);
 869            let snapshot = language_server
 870                .pending_snapshots
 871                .get(&version)
 872                .ok_or_else(|| anyhow!("missing snapshot"))?;
 873            &snapshot.buffer_snapshot
 874        } else {
 875            self.deref()
 876        };
 877
 878        diagnostics.sort_unstable_by(|a, b| {
 879            Ordering::Equal
 880                .then_with(|| a.range.start.cmp(&b.range.start))
 881                .then_with(|| b.range.end.cmp(&a.range.end))
 882                .then_with(|| compare_diagnostics(&a.diagnostic, &b.diagnostic))
 883        });
 884
 885        let mut sanitized_diagnostics = Vec::new();
 886        let mut edits_since_save = content.edits_since::<T>(&self.saved_version).peekable();
 887        let mut last_edit_old_end = T::default();
 888        let mut last_edit_new_end = T::default();
 889        'outer: for entry in diagnostics {
 890            let mut start = entry.range.start;
 891            let mut end = entry.range.end;
 892
 893            // Some diagnostics are based on files on disk instead of buffers'
 894            // current contents. Adjust these diagnostics' ranges to reflect
 895            // any unsaved edits.
 896            if entry.diagnostic.is_disk_based {
 897                while let Some(edit) = edits_since_save.peek() {
 898                    if edit.old.end <= start {
 899                        last_edit_old_end = edit.old.end;
 900                        last_edit_new_end = edit.new.end;
 901                        edits_since_save.next();
 902                    } else if edit.old.start <= end && edit.old.end >= start {
 903                        continue 'outer;
 904                    } else {
 905                        break;
 906                    }
 907                }
 908
 909                let start_overshoot = start - last_edit_old_end;
 910                start = last_edit_new_end;
 911                start.add_assign(&start_overshoot);
 912
 913                let end_overshoot = end - last_edit_old_end;
 914                end = last_edit_new_end;
 915                end.add_assign(&end_overshoot);
 916            }
 917
 918            let range = start.clip(Bias::Left, content)..end.clip(Bias::Right, content);
 919            let mut range = range.start.to_point(content)..range.end.to_point(content);
 920            // Expand empty ranges by one character
 921            if range.start == range.end {
 922                range.end.column += 1;
 923                range.end = content.clip_point(range.end, Bias::Right);
 924                if range.start == range.end && range.end.column > 0 {
 925                    range.start.column -= 1;
 926                    range.start = content.clip_point(range.start, Bias::Left);
 927                }
 928            }
 929
 930            sanitized_diagnostics.push(DiagnosticEntry {
 931                range,
 932                diagnostic: entry.diagnostic,
 933            });
 934        }
 935        drop(edits_since_save);
 936
 937        let set = DiagnosticSet::new(sanitized_diagnostics, content);
 938        self.apply_diagnostic_update(set.clone(), cx);
 939        Ok(Operation::UpdateDiagnostics {
 940            diagnostics: set.iter().cloned().collect(),
 941            lamport_timestamp: self.text.lamport_clock.tick(),
 942        })
 943    }
 944
 945    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 946        if let Some(indent_columns) = self.compute_autoindents() {
 947            let indent_columns = cx.background().spawn(indent_columns);
 948            match cx
 949                .background()
 950                .block_with_timeout(Duration::from_micros(500), indent_columns)
 951            {
 952                Ok(indent_columns) => self.apply_autoindents(indent_columns, cx),
 953                Err(indent_columns) => {
 954                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 955                        let indent_columns = indent_columns.await;
 956                        this.update(&mut cx, |this, cx| {
 957                            this.apply_autoindents(indent_columns, cx);
 958                        });
 959                    }));
 960                }
 961            }
 962        }
 963    }
 964
 965    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, u32>>> {
 966        let max_rows_between_yields = 100;
 967        let snapshot = self.snapshot();
 968        if snapshot.language.is_none()
 969            || snapshot.tree.is_none()
 970            || self.autoindent_requests.is_empty()
 971        {
 972            return None;
 973        }
 974
 975        let autoindent_requests = self.autoindent_requests.clone();
 976        Some(async move {
 977            let mut indent_columns = BTreeMap::new();
 978            for request in autoindent_requests {
 979                let old_to_new_rows = request
 980                    .edited
 981                    .iter()
 982                    .map(|anchor| anchor.summary::<Point>(&request.before_edit).row)
 983                    .zip(
 984                        request
 985                            .edited
 986                            .iter()
 987                            .map(|anchor| anchor.summary::<Point>(&snapshot).row),
 988                    )
 989                    .collect::<BTreeMap<u32, u32>>();
 990
 991                let mut old_suggestions = HashMap::<u32, u32>::default();
 992                let old_edited_ranges =
 993                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 994                for old_edited_range in old_edited_ranges {
 995                    let suggestions = request
 996                        .before_edit
 997                        .suggest_autoindents(old_edited_range.clone())
 998                        .into_iter()
 999                        .flatten();
1000                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1001                        let indentation_basis = old_to_new_rows
1002                            .get(&suggestion.basis_row)
1003                            .and_then(|from_row| old_suggestions.get(from_row).copied())
1004                            .unwrap_or_else(|| {
1005                                request
1006                                    .before_edit
1007                                    .indent_column_for_line(suggestion.basis_row)
1008                            });
1009                        let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
1010                        old_suggestions.insert(
1011                            *old_to_new_rows.get(&old_row).unwrap(),
1012                            indentation_basis + delta,
1013                        );
1014                    }
1015                    yield_now().await;
1016                }
1017
1018                // At this point, old_suggestions contains the suggested indentation for all edited lines with respect to the state of the
1019                // buffer before the edit, but keyed by the row for these lines after the edits were applied.
1020                let new_edited_row_ranges =
1021                    contiguous_ranges(old_to_new_rows.values().copied(), max_rows_between_yields);
1022                for new_edited_row_range in new_edited_row_ranges {
1023                    let suggestions = snapshot
1024                        .suggest_autoindents(new_edited_row_range.clone())
1025                        .into_iter()
1026                        .flatten();
1027                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1028                        let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
1029                        let new_indentation = indent_columns
1030                            .get(&suggestion.basis_row)
1031                            .copied()
1032                            .unwrap_or_else(|| {
1033                                snapshot.indent_column_for_line(suggestion.basis_row)
1034                            })
1035                            + delta;
1036                        if old_suggestions
1037                            .get(&new_row)
1038                            .map_or(true, |old_indentation| new_indentation != *old_indentation)
1039                        {
1040                            indent_columns.insert(new_row, new_indentation);
1041                        }
1042                    }
1043                    yield_now().await;
1044                }
1045
1046                if let Some(inserted) = request.inserted.as_ref() {
1047                    let inserted_row_ranges = contiguous_ranges(
1048                        inserted
1049                            .iter()
1050                            .map(|range| range.to_point(&snapshot))
1051                            .flat_map(|range| range.start.row..range.end.row + 1),
1052                        max_rows_between_yields,
1053                    );
1054                    for inserted_row_range in inserted_row_ranges {
1055                        let suggestions = snapshot
1056                            .suggest_autoindents(inserted_row_range.clone())
1057                            .into_iter()
1058                            .flatten();
1059                        for (row, suggestion) in inserted_row_range.zip(suggestions) {
1060                            let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
1061                            let new_indentation = indent_columns
1062                                .get(&suggestion.basis_row)
1063                                .copied()
1064                                .unwrap_or_else(|| {
1065                                    snapshot.indent_column_for_line(suggestion.basis_row)
1066                                })
1067                                + delta;
1068                            indent_columns.insert(row, new_indentation);
1069                        }
1070                        yield_now().await;
1071                    }
1072                }
1073            }
1074            indent_columns
1075        })
1076    }
1077
1078    fn apply_autoindents(
1079        &mut self,
1080        indent_columns: BTreeMap<u32, u32>,
1081        cx: &mut ModelContext<Self>,
1082    ) {
1083        self.autoindent_requests.clear();
1084        self.start_transaction();
1085        for (row, indent_column) in &indent_columns {
1086            self.set_indent_column_for_line(*row, *indent_column, cx);
1087        }
1088        self.end_transaction(cx);
1089    }
1090
1091    fn set_indent_column_for_line(&mut self, row: u32, column: u32, cx: &mut ModelContext<Self>) {
1092        let current_column = self.indent_column_for_line(row);
1093        if column > current_column {
1094            let offset = Point::new(row, 0).to_offset(&*self);
1095            self.edit(
1096                [offset..offset],
1097                " ".repeat((column - current_column) as usize),
1098                cx,
1099            );
1100        } else if column < current_column {
1101            self.edit(
1102                [Point::new(row, 0)..Point::new(row, current_column - column)],
1103                "",
1104                cx,
1105            );
1106        }
1107    }
1108
1109    pub(crate) fn diff(&self, new_text: Arc<str>, cx: &AppContext) -> Task<Diff> {
1110        // TODO: it would be nice to not allocate here.
1111        let old_text = self.text();
1112        let base_version = self.version();
1113        cx.background().spawn(async move {
1114            let changes = TextDiff::from_lines(old_text.as_str(), new_text.as_ref())
1115                .iter_all_changes()
1116                .map(|c| (c.tag(), c.value().len()))
1117                .collect::<Vec<_>>();
1118            Diff {
1119                base_version,
1120                new_text,
1121                changes,
1122            }
1123        })
1124    }
1125
1126    pub(crate) fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> bool {
1127        if self.version == diff.base_version {
1128            self.start_transaction();
1129            let mut offset = 0;
1130            for (tag, len) in diff.changes {
1131                let range = offset..(offset + len);
1132                match tag {
1133                    ChangeTag::Equal => offset += len,
1134                    ChangeTag::Delete => self.edit(Some(range), "", cx),
1135                    ChangeTag::Insert => {
1136                        self.edit(Some(offset..offset), &diff.new_text[range], cx);
1137                        offset += len;
1138                    }
1139                }
1140            }
1141            self.end_transaction(cx);
1142            true
1143        } else {
1144            false
1145        }
1146    }
1147
1148    pub fn is_dirty(&self) -> bool {
1149        !self.saved_version.observed_all(&self.version)
1150            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1151    }
1152
1153    pub fn has_conflict(&self) -> bool {
1154        !self.saved_version.observed_all(&self.version)
1155            && self
1156                .file
1157                .as_ref()
1158                .map_or(false, |file| file.mtime() > self.saved_mtime)
1159    }
1160
1161    pub fn subscribe(&mut self) -> Subscription {
1162        self.text.subscribe()
1163    }
1164
1165    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1166        self.start_transaction_at(Instant::now())
1167    }
1168
1169    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1170        self.text.start_transaction_at(now)
1171    }
1172
1173    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1174        self.end_transaction_at(Instant::now(), cx)
1175    }
1176
1177    pub fn end_transaction_at(
1178        &mut self,
1179        now: Instant,
1180        cx: &mut ModelContext<Self>,
1181    ) -> Option<TransactionId> {
1182        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1183            let was_dirty = start_version != self.saved_version;
1184            self.did_edit(&start_version, was_dirty, cx);
1185            Some(transaction_id)
1186        } else {
1187            None
1188        }
1189    }
1190
1191    pub fn set_active_selections(
1192        &mut self,
1193        selections: Arc<[Selection<Anchor>]>,
1194        cx: &mut ModelContext<Self>,
1195    ) {
1196        let lamport_timestamp = self.text.lamport_clock.tick();
1197        self.remote_selections.insert(
1198            self.text.replica_id(),
1199            SelectionSet {
1200                selections: selections.clone(),
1201                lamport_timestamp,
1202            },
1203        );
1204        self.send_operation(
1205            Operation::UpdateSelections {
1206                replica_id: self.text.replica_id(),
1207                selections,
1208                lamport_timestamp,
1209            },
1210            cx,
1211        );
1212    }
1213
1214    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1215        self.set_active_selections(Arc::from([]), cx);
1216    }
1217
1218    fn update_language_server(&mut self) {
1219        let language_server = if let Some(language_server) = self.language_server.as_mut() {
1220            language_server
1221        } else {
1222            return;
1223        };
1224        let abs_path = self
1225            .file
1226            .as_ref()
1227            .map_or(Path::new("/").to_path_buf(), |file| {
1228                file.abs_path().unwrap()
1229            });
1230
1231        let version = post_inc(&mut language_server.next_version);
1232        let snapshot = LanguageServerSnapshot {
1233            buffer_snapshot: self.text.snapshot(),
1234            version,
1235            path: Arc::from(abs_path),
1236        };
1237        language_server
1238            .pending_snapshots
1239            .insert(version, snapshot.clone());
1240        let _ = language_server
1241            .latest_snapshot
1242            .blocking_send(Some(snapshot));
1243    }
1244
1245    pub fn edit<I, S, T>(&mut self, ranges_iter: I, new_text: T, cx: &mut ModelContext<Self>)
1246    where
1247        I: IntoIterator<Item = Range<S>>,
1248        S: ToOffset,
1249        T: Into<String>,
1250    {
1251        self.edit_internal(ranges_iter, new_text, false, cx)
1252    }
1253
1254    pub fn edit_with_autoindent<I, S, T>(
1255        &mut self,
1256        ranges_iter: I,
1257        new_text: T,
1258        cx: &mut ModelContext<Self>,
1259    ) where
1260        I: IntoIterator<Item = Range<S>>,
1261        S: ToOffset,
1262        T: Into<String>,
1263    {
1264        self.edit_internal(ranges_iter, new_text, true, cx)
1265    }
1266
1267    pub fn edit_internal<I, S, T>(
1268        &mut self,
1269        ranges_iter: I,
1270        new_text: T,
1271        autoindent: bool,
1272        cx: &mut ModelContext<Self>,
1273    ) where
1274        I: IntoIterator<Item = Range<S>>,
1275        S: ToOffset,
1276        T: Into<String>,
1277    {
1278        let new_text = new_text.into();
1279
1280        // Skip invalid ranges and coalesce contiguous ones.
1281        let mut ranges: Vec<Range<usize>> = Vec::new();
1282        for range in ranges_iter {
1283            let range = range.start.to_offset(self)..range.end.to_offset(self);
1284            if !new_text.is_empty() || !range.is_empty() {
1285                if let Some(prev_range) = ranges.last_mut() {
1286                    if prev_range.end >= range.start {
1287                        prev_range.end = cmp::max(prev_range.end, range.end);
1288                    } else {
1289                        ranges.push(range);
1290                    }
1291                } else {
1292                    ranges.push(range);
1293                }
1294            }
1295        }
1296        if ranges.is_empty() {
1297            return;
1298        }
1299
1300        self.start_transaction();
1301        self.pending_autoindent.take();
1302        let autoindent_request = if autoindent && self.language.is_some() {
1303            let before_edit = self.snapshot();
1304            let edited = ranges
1305                .iter()
1306                .filter_map(|range| {
1307                    let start = range.start.to_point(self);
1308                    if new_text.starts_with('\n') && start.column == self.line_len(start.row) {
1309                        None
1310                    } else {
1311                        Some(self.anchor_before(range.start))
1312                    }
1313                })
1314                .collect();
1315            Some((before_edit, edited))
1316        } else {
1317            None
1318        };
1319
1320        let first_newline_ix = new_text.find('\n');
1321        let new_text_len = new_text.len();
1322
1323        let edit = self.text.edit(ranges.iter().cloned(), new_text);
1324
1325        if let Some((before_edit, edited)) = autoindent_request {
1326            let mut inserted = None;
1327            if let Some(first_newline_ix) = first_newline_ix {
1328                let mut delta = 0isize;
1329                inserted = Some(
1330                    ranges
1331                        .iter()
1332                        .map(|range| {
1333                            let start =
1334                                (delta + range.start as isize) as usize + first_newline_ix + 1;
1335                            let end = (delta + range.start as isize) as usize + new_text_len;
1336                            delta +=
1337                                (range.end as isize - range.start as isize) + new_text_len as isize;
1338                            self.anchor_before(start)..self.anchor_after(end)
1339                        })
1340                        .collect(),
1341                );
1342            }
1343
1344            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1345                before_edit,
1346                edited,
1347                inserted,
1348            }));
1349        }
1350
1351        self.end_transaction(cx);
1352        self.send_operation(Operation::Buffer(text::Operation::Edit(edit)), cx);
1353    }
1354
1355    fn did_edit(
1356        &mut self,
1357        old_version: &clock::Global,
1358        was_dirty: bool,
1359        cx: &mut ModelContext<Self>,
1360    ) {
1361        if self.edits_since::<usize>(old_version).next().is_none() {
1362            return;
1363        }
1364
1365        self.reparse(cx);
1366        self.update_language_server();
1367
1368        cx.emit(Event::Edited);
1369        if !was_dirty {
1370            cx.emit(Event::Dirtied);
1371        }
1372        cx.notify();
1373    }
1374
1375    fn grammar(&self) -> Option<&Arc<Grammar>> {
1376        self.language.as_ref().and_then(|l| l.grammar.as_ref())
1377    }
1378
1379    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1380        &mut self,
1381        ops: I,
1382        cx: &mut ModelContext<Self>,
1383    ) -> Result<()> {
1384        self.pending_autoindent.take();
1385        let was_dirty = self.is_dirty();
1386        let old_version = self.version.clone();
1387        let mut deferred_ops = Vec::new();
1388        let buffer_ops = ops
1389            .into_iter()
1390            .filter_map(|op| match op {
1391                Operation::Buffer(op) => Some(op),
1392                _ => {
1393                    if self.can_apply_op(&op) {
1394                        self.apply_op(op, cx);
1395                    } else {
1396                        deferred_ops.push(op);
1397                    }
1398                    None
1399                }
1400            })
1401            .collect::<Vec<_>>();
1402        self.text.apply_ops(buffer_ops)?;
1403        self.deferred_ops.insert(deferred_ops);
1404        self.flush_deferred_ops(cx);
1405        self.did_edit(&old_version, was_dirty, cx);
1406        // Notify independently of whether the buffer was edited as the operations could include a
1407        // selection update.
1408        cx.notify();
1409        Ok(())
1410    }
1411
1412    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1413        let mut deferred_ops = Vec::new();
1414        for op in self.deferred_ops.drain().iter().cloned() {
1415            if self.can_apply_op(&op) {
1416                self.apply_op(op, cx);
1417            } else {
1418                deferred_ops.push(op);
1419            }
1420        }
1421        self.deferred_ops.insert(deferred_ops);
1422    }
1423
1424    fn can_apply_op(&self, operation: &Operation) -> bool {
1425        match operation {
1426            Operation::Buffer(_) => {
1427                unreachable!("buffer operations should never be applied at this layer")
1428            }
1429            Operation::UpdateDiagnostics {
1430                diagnostics: diagnostic_set,
1431                ..
1432            } => diagnostic_set.iter().all(|diagnostic| {
1433                self.text.can_resolve(&diagnostic.range.start)
1434                    && self.text.can_resolve(&diagnostic.range.end)
1435            }),
1436            Operation::UpdateSelections { selections, .. } => selections
1437                .iter()
1438                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1439        }
1440    }
1441
1442    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1443        match operation {
1444            Operation::Buffer(_) => {
1445                unreachable!("buffer operations should never be applied at this layer")
1446            }
1447            Operation::UpdateDiagnostics {
1448                diagnostics: diagnostic_set,
1449                ..
1450            } => {
1451                let snapshot = self.snapshot();
1452                self.apply_diagnostic_update(
1453                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1454                    cx,
1455                );
1456            }
1457            Operation::UpdateSelections {
1458                replica_id,
1459                selections,
1460                lamport_timestamp,
1461            } => {
1462                if let Some(set) = self.remote_selections.get(&replica_id) {
1463                    if set.lamport_timestamp > lamport_timestamp {
1464                        return;
1465                    }
1466                }
1467
1468                self.remote_selections.insert(
1469                    replica_id,
1470                    SelectionSet {
1471                        selections,
1472                        lamport_timestamp,
1473                    },
1474                );
1475                self.text.lamport_clock.observe(lamport_timestamp);
1476                self.selections_update_count += 1;
1477            }
1478        }
1479    }
1480
1481    fn apply_diagnostic_update(&mut self, diagnostics: DiagnosticSet, cx: &mut ModelContext<Self>) {
1482        self.diagnostics = diagnostics;
1483        self.diagnostics_update_count += 1;
1484        cx.notify();
1485        cx.emit(Event::DiagnosticsUpdated);
1486    }
1487
1488    #[cfg(not(test))]
1489    pub fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1490        if let Some(file) = &self.file {
1491            file.buffer_updated(self.remote_id(), operation, cx.as_mut());
1492        }
1493    }
1494
1495    #[cfg(test)]
1496    pub fn send_operation(&mut self, operation: Operation, _: &mut ModelContext<Self>) {
1497        self.operations.push(operation);
1498    }
1499
1500    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1501        self.remote_selections.remove(&replica_id);
1502        cx.notify();
1503    }
1504
1505    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1506        let was_dirty = self.is_dirty();
1507        let old_version = self.version.clone();
1508
1509        if let Some((transaction_id, operation)) = self.text.undo() {
1510            self.send_operation(Operation::Buffer(operation), cx);
1511            self.did_edit(&old_version, was_dirty, cx);
1512            Some(transaction_id)
1513        } else {
1514            None
1515        }
1516    }
1517
1518    pub fn undo_transaction(
1519        &mut self,
1520        transaction_id: TransactionId,
1521        cx: &mut ModelContext<Self>,
1522    ) -> bool {
1523        let was_dirty = self.is_dirty();
1524        let old_version = self.version.clone();
1525
1526        if let Some(operation) = self.text.undo_transaction(transaction_id) {
1527            self.send_operation(Operation::Buffer(operation), cx);
1528            self.did_edit(&old_version, was_dirty, cx);
1529            true
1530        } else {
1531            false
1532        }
1533    }
1534
1535    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1536        let was_dirty = self.is_dirty();
1537        let old_version = self.version.clone();
1538
1539        if let Some((transaction_id, operation)) = self.text.redo() {
1540            self.send_operation(Operation::Buffer(operation), cx);
1541            self.did_edit(&old_version, was_dirty, cx);
1542            Some(transaction_id)
1543        } else {
1544            None
1545        }
1546    }
1547
1548    pub fn redo_transaction(
1549        &mut self,
1550        transaction_id: TransactionId,
1551        cx: &mut ModelContext<Self>,
1552    ) -> bool {
1553        let was_dirty = self.is_dirty();
1554        let old_version = self.version.clone();
1555
1556        if let Some(operation) = self.text.redo_transaction(transaction_id) {
1557            self.send_operation(Operation::Buffer(operation), cx);
1558            self.did_edit(&old_version, was_dirty, cx);
1559            true
1560        } else {
1561            false
1562        }
1563    }
1564}
1565
1566#[cfg(any(test, feature = "test-support"))]
1567impl Buffer {
1568    pub fn set_group_interval(&mut self, group_interval: Duration) {
1569        self.text.set_group_interval(group_interval);
1570    }
1571
1572    pub fn randomly_edit<T>(
1573        &mut self,
1574        rng: &mut T,
1575        old_range_count: usize,
1576        cx: &mut ModelContext<Self>,
1577    ) where
1578        T: rand::Rng,
1579    {
1580        let mut old_ranges: Vec<Range<usize>> = Vec::new();
1581        for _ in 0..old_range_count {
1582            let last_end = old_ranges.last().map_or(0, |last_range| last_range.end + 1);
1583            if last_end > self.len() {
1584                break;
1585            }
1586            old_ranges.push(self.text.random_byte_range(last_end, rng));
1587        }
1588        let new_text_len = rng.gen_range(0..10);
1589        let new_text: String = crate::random_char_iter::RandomCharIter::new(&mut *rng)
1590            .take(new_text_len)
1591            .collect();
1592        log::info!(
1593            "mutating buffer {} at {:?}: {:?}",
1594            self.replica_id(),
1595            old_ranges,
1596            new_text
1597        );
1598        self.edit(old_ranges.iter().cloned(), new_text.as_str(), cx);
1599    }
1600
1601    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1602        let was_dirty = self.is_dirty();
1603        let old_version = self.version.clone();
1604
1605        let ops = self.text.randomly_undo_redo(rng);
1606        if !ops.is_empty() {
1607            for op in ops {
1608                self.send_operation(Operation::Buffer(op), cx);
1609                self.did_edit(&old_version, was_dirty, cx);
1610            }
1611        }
1612    }
1613}
1614
1615impl Entity for Buffer {
1616    type Event = Event;
1617
1618    fn release(&mut self, cx: &mut gpui::MutableAppContext) {
1619        if let Some(file) = self.file.as_ref() {
1620            file.buffer_removed(self.remote_id(), cx);
1621        }
1622    }
1623}
1624
1625impl Deref for Buffer {
1626    type Target = TextBuffer;
1627
1628    fn deref(&self) -> &Self::Target {
1629        &self.text
1630    }
1631}
1632
1633impl BufferSnapshot {
1634    fn suggest_autoindents<'a>(
1635        &'a self,
1636        row_range: Range<u32>,
1637    ) -> Option<impl Iterator<Item = IndentSuggestion> + 'a> {
1638        let mut query_cursor = QueryCursorHandle::new();
1639        if let Some((grammar, tree)) = self.grammar().zip(self.tree.as_ref()) {
1640            let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1641
1642            // Get the "indentation ranges" that intersect this row range.
1643            let indent_capture_ix = grammar.indents_query.capture_index_for_name("indent");
1644            let end_capture_ix = grammar.indents_query.capture_index_for_name("end");
1645            query_cursor.set_point_range(
1646                Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0).to_ts_point()
1647                    ..Point::new(row_range.end, 0).to_ts_point(),
1648            );
1649            let mut indentation_ranges = Vec::<(Range<Point>, &'static str)>::new();
1650            for mat in query_cursor.matches(
1651                &grammar.indents_query,
1652                tree.root_node(),
1653                TextProvider(self.as_rope()),
1654            ) {
1655                let mut node_kind = "";
1656                let mut start: Option<Point> = None;
1657                let mut end: Option<Point> = None;
1658                for capture in mat.captures {
1659                    if Some(capture.index) == indent_capture_ix {
1660                        node_kind = capture.node.kind();
1661                        start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1662                        end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1663                    } else if Some(capture.index) == end_capture_ix {
1664                        end = Some(Point::from_ts_point(capture.node.start_position().into()));
1665                    }
1666                }
1667
1668                if let Some((start, end)) = start.zip(end) {
1669                    if start.row == end.row {
1670                        continue;
1671                    }
1672
1673                    let range = start..end;
1674                    match indentation_ranges.binary_search_by_key(&range.start, |r| r.0.start) {
1675                        Err(ix) => indentation_ranges.insert(ix, (range, node_kind)),
1676                        Ok(ix) => {
1677                            let prev_range = &mut indentation_ranges[ix];
1678                            prev_range.0.end = prev_range.0.end.max(range.end);
1679                        }
1680                    }
1681                }
1682            }
1683
1684            let mut prev_row = prev_non_blank_row.unwrap_or(0);
1685            Some(row_range.map(move |row| {
1686                let row_start = Point::new(row, self.indent_column_for_line(row));
1687
1688                let mut indent_from_prev_row = false;
1689                let mut outdent_to_row = u32::MAX;
1690                for (range, _node_kind) in &indentation_ranges {
1691                    if range.start.row >= row {
1692                        break;
1693                    }
1694
1695                    if range.start.row == prev_row && range.end > row_start {
1696                        indent_from_prev_row = true;
1697                    }
1698                    if range.end.row >= prev_row && range.end <= row_start {
1699                        outdent_to_row = outdent_to_row.min(range.start.row);
1700                    }
1701                }
1702
1703                let suggestion = if outdent_to_row == prev_row {
1704                    IndentSuggestion {
1705                        basis_row: prev_row,
1706                        indent: false,
1707                    }
1708                } else if indent_from_prev_row {
1709                    IndentSuggestion {
1710                        basis_row: prev_row,
1711                        indent: true,
1712                    }
1713                } else if outdent_to_row < prev_row {
1714                    IndentSuggestion {
1715                        basis_row: outdent_to_row,
1716                        indent: false,
1717                    }
1718                } else {
1719                    IndentSuggestion {
1720                        basis_row: prev_row,
1721                        indent: false,
1722                    }
1723                };
1724
1725                prev_row = row;
1726                suggestion
1727            }))
1728        } else {
1729            None
1730        }
1731    }
1732
1733    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
1734        while row > 0 {
1735            row -= 1;
1736            if !self.is_line_blank(row) {
1737                return Some(row);
1738            }
1739        }
1740        None
1741    }
1742
1743    pub fn chunks<'a, T: ToOffset>(
1744        &'a self,
1745        range: Range<T>,
1746        theme: Option<&'a SyntaxTheme>,
1747    ) -> BufferChunks<'a> {
1748        let range = range.start.to_offset(self)..range.end.to_offset(self);
1749
1750        let mut highlights = None;
1751        let mut diagnostic_endpoints = Vec::<DiagnosticEndpoint>::new();
1752        if let Some(theme) = theme {
1753            for entry in self.diagnostics_in_range::<_, usize>(range.clone()) {
1754                diagnostic_endpoints.push(DiagnosticEndpoint {
1755                    offset: entry.range.start,
1756                    is_start: true,
1757                    severity: entry.diagnostic.severity,
1758                });
1759                diagnostic_endpoints.push(DiagnosticEndpoint {
1760                    offset: entry.range.end,
1761                    is_start: false,
1762                    severity: entry.diagnostic.severity,
1763                });
1764            }
1765            diagnostic_endpoints
1766                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
1767
1768            if let Some((grammar, tree)) = self.grammar().zip(self.tree.as_ref()) {
1769                let mut query_cursor = QueryCursorHandle::new();
1770
1771                // TODO - add a Tree-sitter API to remove the need for this.
1772                let cursor = unsafe {
1773                    std::mem::transmute::<_, &'static mut QueryCursor>(query_cursor.deref_mut())
1774                };
1775                let captures = cursor.set_byte_range(range.clone()).captures(
1776                    &grammar.highlights_query,
1777                    tree.root_node(),
1778                    TextProvider(self.text.as_rope()),
1779                );
1780                highlights = Some(BufferChunkHighlights {
1781                    captures,
1782                    next_capture: None,
1783                    stack: Default::default(),
1784                    highlight_map: grammar.highlight_map(),
1785                    _query_cursor: query_cursor,
1786                    theme,
1787                })
1788            }
1789        }
1790
1791        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
1792        let chunks = self.text.as_rope().chunks_in_range(range.clone());
1793
1794        BufferChunks {
1795            range,
1796            chunks,
1797            diagnostic_endpoints,
1798            error_depth: 0,
1799            warning_depth: 0,
1800            information_depth: 0,
1801            hint_depth: 0,
1802            highlights,
1803        }
1804    }
1805
1806    pub fn language(&self) -> Option<&Arc<Language>> {
1807        self.language.as_ref()
1808    }
1809
1810    fn grammar(&self) -> Option<&Arc<Grammar>> {
1811        self.language
1812            .as_ref()
1813            .and_then(|language| language.grammar.as_ref())
1814    }
1815
1816    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
1817        if let Some(tree) = self.tree.as_ref() {
1818            let root = tree.root_node();
1819            let range = range.start.to_offset(self)..range.end.to_offset(self);
1820            let mut node = root.descendant_for_byte_range(range.start, range.end);
1821            while node.map_or(false, |n| n.byte_range() == range) {
1822                node = node.unwrap().parent();
1823            }
1824            node.map(|n| n.byte_range())
1825        } else {
1826            None
1827        }
1828    }
1829
1830    pub fn enclosing_bracket_ranges<T: ToOffset>(
1831        &self,
1832        range: Range<T>,
1833    ) -> Option<(Range<usize>, Range<usize>)> {
1834        let (grammar, tree) = self.grammar().zip(self.tree.as_ref())?;
1835        let open_capture_ix = grammar.brackets_query.capture_index_for_name("open")?;
1836        let close_capture_ix = grammar.brackets_query.capture_index_for_name("close")?;
1837
1838        // Find bracket pairs that *inclusively* contain the given range.
1839        let range = range.start.to_offset(self).saturating_sub(1)..range.end.to_offset(self) + 1;
1840        let mut cursor = QueryCursorHandle::new();
1841        let matches = cursor.set_byte_range(range).matches(
1842            &grammar.brackets_query,
1843            tree.root_node(),
1844            TextProvider(self.as_rope()),
1845        );
1846
1847        // Get the ranges of the innermost pair of brackets.
1848        matches
1849            .filter_map(|mat| {
1850                let open = mat.nodes_for_capture_index(open_capture_ix).next()?;
1851                let close = mat.nodes_for_capture_index(close_capture_ix).next()?;
1852                Some((open.byte_range(), close.byte_range()))
1853            })
1854            .min_by_key(|(open_range, close_range)| close_range.end - open_range.start)
1855    }
1856
1857    pub fn remote_selections_in_range<'a>(
1858        &'a self,
1859        range: Range<Anchor>,
1860    ) -> impl 'a + Iterator<Item = (ReplicaId, impl 'a + Iterator<Item = &'a Selection<Anchor>>)>
1861    {
1862        self.remote_selections
1863            .iter()
1864            .filter(|(replica_id, set)| {
1865                **replica_id != self.text.replica_id() && !set.selections.is_empty()
1866            })
1867            .map(move |(replica_id, set)| {
1868                let start_ix = match set.selections.binary_search_by(|probe| {
1869                    probe
1870                        .end
1871                        .cmp(&range.start, self)
1872                        .unwrap()
1873                        .then(Ordering::Greater)
1874                }) {
1875                    Ok(ix) | Err(ix) => ix,
1876                };
1877                let end_ix = match set.selections.binary_search_by(|probe| {
1878                    probe
1879                        .start
1880                        .cmp(&range.end, self)
1881                        .unwrap()
1882                        .then(Ordering::Less)
1883                }) {
1884                    Ok(ix) | Err(ix) => ix,
1885                };
1886
1887                (*replica_id, set.selections[start_ix..end_ix].iter())
1888            })
1889    }
1890
1891    pub fn diagnostics_in_range<'a, T, O>(
1892        &'a self,
1893        search_range: Range<T>,
1894    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1895    where
1896        T: 'a + Clone + ToOffset,
1897        O: 'a + FromAnchor,
1898    {
1899        self.diagnostics.range(search_range.clone(), self, true)
1900    }
1901
1902    pub fn diagnostic_groups(&self) -> Vec<DiagnosticGroup<Anchor>> {
1903        let mut groups = Vec::new();
1904        self.diagnostics.groups(&mut groups, self);
1905        groups
1906    }
1907
1908    pub fn diagnostic_group<'a, O>(
1909        &'a self,
1910        group_id: usize,
1911    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1912    where
1913        O: 'a + FromAnchor,
1914    {
1915        self.diagnostics.group(group_id, self)
1916    }
1917
1918    pub fn diagnostics_update_count(&self) -> usize {
1919        self.diagnostics_update_count
1920    }
1921
1922    pub fn parse_count(&self) -> usize {
1923        self.parse_count
1924    }
1925
1926    pub fn selections_update_count(&self) -> usize {
1927        self.selections_update_count
1928    }
1929}
1930
1931impl Clone for BufferSnapshot {
1932    fn clone(&self) -> Self {
1933        Self {
1934            text: self.text.clone(),
1935            tree: self.tree.clone(),
1936            remote_selections: self.remote_selections.clone(),
1937            diagnostics: self.diagnostics.clone(),
1938            selections_update_count: self.selections_update_count,
1939            diagnostics_update_count: self.diagnostics_update_count,
1940            is_parsing: self.is_parsing,
1941            language: self.language.clone(),
1942            parse_count: self.parse_count,
1943        }
1944    }
1945}
1946
1947impl Deref for BufferSnapshot {
1948    type Target = text::BufferSnapshot;
1949
1950    fn deref(&self) -> &Self::Target {
1951        &self.text
1952    }
1953}
1954
1955impl<'a> tree_sitter::TextProvider<'a> for TextProvider<'a> {
1956    type I = ByteChunks<'a>;
1957
1958    fn text(&mut self, node: tree_sitter::Node) -> Self::I {
1959        ByteChunks(self.0.chunks_in_range(node.byte_range()))
1960    }
1961}
1962
1963struct ByteChunks<'a>(rope::Chunks<'a>);
1964
1965impl<'a> Iterator for ByteChunks<'a> {
1966    type Item = &'a [u8];
1967
1968    fn next(&mut self) -> Option<Self::Item> {
1969        self.0.next().map(str::as_bytes)
1970    }
1971}
1972
1973unsafe impl<'a> Send for BufferChunks<'a> {}
1974
1975impl<'a> BufferChunks<'a> {
1976    pub fn seek(&mut self, offset: usize) {
1977        self.range.start = offset;
1978        self.chunks.seek(self.range.start);
1979        if let Some(highlights) = self.highlights.as_mut() {
1980            highlights
1981                .stack
1982                .retain(|(end_offset, _)| *end_offset > offset);
1983            if let Some((mat, capture_ix)) = &highlights.next_capture {
1984                let capture = mat.captures[*capture_ix as usize];
1985                if offset >= capture.node.start_byte() {
1986                    let next_capture_end = capture.node.end_byte();
1987                    if offset < next_capture_end {
1988                        highlights.stack.push((
1989                            next_capture_end,
1990                            highlights.highlight_map.get(capture.index),
1991                        ));
1992                    }
1993                    highlights.next_capture.take();
1994                }
1995            }
1996            highlights.captures.set_byte_range(self.range.clone());
1997        }
1998    }
1999
2000    pub fn offset(&self) -> usize {
2001        self.range.start
2002    }
2003
2004    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2005        let depth = match endpoint.severity {
2006            DiagnosticSeverity::ERROR => &mut self.error_depth,
2007            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2008            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2009            DiagnosticSeverity::HINT => &mut self.hint_depth,
2010            _ => return,
2011        };
2012        if endpoint.is_start {
2013            *depth += 1;
2014        } else {
2015            *depth -= 1;
2016        }
2017    }
2018
2019    fn current_diagnostic_severity(&mut self) -> Option<DiagnosticSeverity> {
2020        if self.error_depth > 0 {
2021            Some(DiagnosticSeverity::ERROR)
2022        } else if self.warning_depth > 0 {
2023            Some(DiagnosticSeverity::WARNING)
2024        } else if self.information_depth > 0 {
2025            Some(DiagnosticSeverity::INFORMATION)
2026        } else if self.hint_depth > 0 {
2027            Some(DiagnosticSeverity::HINT)
2028        } else {
2029            None
2030        }
2031    }
2032}
2033
2034impl<'a> Iterator for BufferChunks<'a> {
2035    type Item = Chunk<'a>;
2036
2037    fn next(&mut self) -> Option<Self::Item> {
2038        let mut next_capture_start = usize::MAX;
2039        let mut next_diagnostic_endpoint = usize::MAX;
2040
2041        if let Some(highlights) = self.highlights.as_mut() {
2042            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2043                if *parent_capture_end <= self.range.start {
2044                    highlights.stack.pop();
2045                } else {
2046                    break;
2047                }
2048            }
2049
2050            if highlights.next_capture.is_none() {
2051                highlights.next_capture = highlights.captures.next();
2052            }
2053
2054            while let Some((mat, capture_ix)) = highlights.next_capture.as_ref() {
2055                let capture = mat.captures[*capture_ix as usize];
2056                if self.range.start < capture.node.start_byte() {
2057                    next_capture_start = capture.node.start_byte();
2058                    break;
2059                } else {
2060                    let highlight_id = highlights.highlight_map.get(capture.index);
2061                    highlights
2062                        .stack
2063                        .push((capture.node.end_byte(), highlight_id));
2064                    highlights.next_capture = highlights.captures.next();
2065                }
2066            }
2067        }
2068
2069        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2070            if endpoint.offset <= self.range.start {
2071                self.update_diagnostic_depths(endpoint);
2072                self.diagnostic_endpoints.next();
2073            } else {
2074                next_diagnostic_endpoint = endpoint.offset;
2075                break;
2076            }
2077        }
2078
2079        if let Some(chunk) = self.chunks.peek() {
2080            let chunk_start = self.range.start;
2081            let mut chunk_end = (self.chunks.offset() + chunk.len())
2082                .min(next_capture_start)
2083                .min(next_diagnostic_endpoint);
2084            let mut highlight_style = None;
2085            if let Some(highlights) = self.highlights.as_ref() {
2086                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2087                    chunk_end = chunk_end.min(*parent_capture_end);
2088                    highlight_style = parent_highlight_id.style(highlights.theme);
2089                }
2090            }
2091
2092            let slice =
2093                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2094            self.range.start = chunk_end;
2095            if self.range.start == self.chunks.offset() + chunk.len() {
2096                self.chunks.next().unwrap();
2097            }
2098
2099            Some(Chunk {
2100                text: slice,
2101                highlight_style,
2102                diagnostic: self.current_diagnostic_severity(),
2103            })
2104        } else {
2105            None
2106        }
2107    }
2108}
2109
2110impl QueryCursorHandle {
2111    fn new() -> Self {
2112        QueryCursorHandle(Some(
2113            QUERY_CURSORS
2114                .lock()
2115                .pop()
2116                .unwrap_or_else(|| QueryCursor::new()),
2117        ))
2118    }
2119}
2120
2121impl Deref for QueryCursorHandle {
2122    type Target = QueryCursor;
2123
2124    fn deref(&self) -> &Self::Target {
2125        self.0.as_ref().unwrap()
2126    }
2127}
2128
2129impl DerefMut for QueryCursorHandle {
2130    fn deref_mut(&mut self) -> &mut Self::Target {
2131        self.0.as_mut().unwrap()
2132    }
2133}
2134
2135impl Drop for QueryCursorHandle {
2136    fn drop(&mut self) {
2137        let mut cursor = self.0.take().unwrap();
2138        cursor.set_byte_range(0..usize::MAX);
2139        cursor.set_point_range(Point::zero().to_ts_point()..Point::MAX.to_ts_point());
2140        QUERY_CURSORS.lock().push(cursor)
2141    }
2142}
2143
2144trait ToTreeSitterPoint {
2145    fn to_ts_point(self) -> tree_sitter::Point;
2146    fn from_ts_point(point: tree_sitter::Point) -> Self;
2147}
2148
2149impl ToTreeSitterPoint for Point {
2150    fn to_ts_point(self) -> tree_sitter::Point {
2151        tree_sitter::Point::new(self.row as usize, self.column as usize)
2152    }
2153
2154    fn from_ts_point(point: tree_sitter::Point) -> Self {
2155        Point::new(point.row as u32, point.column as u32)
2156    }
2157}
2158
2159impl operation_queue::Operation for Operation {
2160    fn lamport_timestamp(&self) -> clock::Lamport {
2161        match self {
2162            Operation::Buffer(_) => {
2163                unreachable!("buffer operations should never be deferred at this layer")
2164            }
2165            Operation::UpdateDiagnostics {
2166                lamport_timestamp, ..
2167            }
2168            | Operation::UpdateSelections {
2169                lamport_timestamp, ..
2170            } => *lamport_timestamp,
2171        }
2172    }
2173}
2174
2175impl Default for Diagnostic {
2176    fn default() -> Self {
2177        Self {
2178            code: Default::default(),
2179            severity: DiagnosticSeverity::ERROR,
2180            message: Default::default(),
2181            group_id: Default::default(),
2182            is_primary: Default::default(),
2183            is_valid: true,
2184            is_disk_based: false,
2185        }
2186    }
2187}
2188
2189pub fn contiguous_ranges(
2190    values: impl Iterator<Item = u32>,
2191    max_len: usize,
2192) -> impl Iterator<Item = Range<u32>> {
2193    let mut values = values.into_iter();
2194    let mut current_range: Option<Range<u32>> = None;
2195    std::iter::from_fn(move || loop {
2196        if let Some(value) = values.next() {
2197            if let Some(range) = &mut current_range {
2198                if value == range.end && range.len() < max_len {
2199                    range.end += 1;
2200                    continue;
2201                }
2202            }
2203
2204            let prev_range = current_range.clone();
2205            current_range = Some(value..(value + 1));
2206            if prev_range.is_some() {
2207                return prev_range;
2208            }
2209        } else {
2210            return current_range.take();
2211        }
2212    })
2213}