buffer.rs

   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    syntax_map::{
  10        SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxSnapshot, ToTreeSitterPoint,
  11    },
  12    CodeLabel, Outline,
  13};
  14use anyhow::{anyhow, Result};
  15use clock::ReplicaId;
  16use futures::FutureExt as _;
  17use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, MutableAppContext, Task};
  18use parking_lot::Mutex;
  19use settings::Settings;
  20use similar::{ChangeTag, TextDiff};
  21use smol::future::yield_now;
  22use std::{
  23    any::Any,
  24    cmp::{self, Ordering},
  25    collections::BTreeMap,
  26    ffi::OsStr,
  27    future::Future,
  28    iter::{self, Iterator, Peekable},
  29    mem,
  30    ops::{Deref, Range},
  31    path::{Path, PathBuf},
  32    str,
  33    sync::Arc,
  34    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  35    vec,
  36};
  37use sum_tree::TreeMap;
  38use text::operation_queue::OperationQueue;
  39pub use text::{Buffer as TextBuffer, BufferSnapshot as TextBufferSnapshot, Operation as _, *};
  40use theme::SyntaxTheme;
  41use util::TryFutureExt as _;
  42
  43#[cfg(any(test, feature = "test-support"))]
  44pub use {tree_sitter_rust, tree_sitter_typescript};
  45
  46pub use lsp::DiagnosticSeverity;
  47
  48pub struct Buffer {
  49    text: TextBuffer,
  50    file: Option<Arc<dyn File>>,
  51    saved_version: clock::Global,
  52    saved_version_fingerprint: String,
  53    saved_mtime: SystemTime,
  54    transaction_depth: usize,
  55    was_dirty_before_starting_transaction: Option<bool>,
  56    language: Option<Arc<Language>>,
  57    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  58    pending_autoindent: Option<Task<()>>,
  59    sync_parse_timeout: Duration,
  60    syntax_map: Mutex<SyntaxMap>,
  61    parsing_in_background: bool,
  62    parse_count: usize,
  63    diagnostics: DiagnosticSet,
  64    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  65    selections_update_count: usize,
  66    diagnostics_update_count: usize,
  67    diagnostics_timestamp: clock::Lamport,
  68    file_update_count: usize,
  69    completion_triggers: Vec<String>,
  70    completion_triggers_timestamp: clock::Lamport,
  71    deferred_ops: OperationQueue<Operation>,
  72}
  73
  74pub struct BufferSnapshot {
  75    text: text::BufferSnapshot,
  76    pub(crate) syntax: SyntaxSnapshot,
  77    file: Option<Arc<dyn File>>,
  78    diagnostics: DiagnosticSet,
  79    diagnostics_update_count: usize,
  80    file_update_count: usize,
  81    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  82    selections_update_count: usize,
  83    language: Option<Arc<Language>>,
  84    parse_count: usize,
  85}
  86
  87#[derive(Clone, Copy, Debug, PartialEq, Eq)]
  88pub struct IndentSize {
  89    pub len: u32,
  90    pub kind: IndentKind,
  91}
  92
  93#[derive(Clone, Copy, Debug, PartialEq, Eq)]
  94pub enum IndentKind {
  95    Space,
  96    Tab,
  97}
  98
  99#[derive(Clone, Debug)]
 100struct SelectionSet {
 101    line_mode: bool,
 102    selections: Arc<[Selection<Anchor>]>,
 103    lamport_timestamp: clock::Lamport,
 104}
 105
 106#[derive(Clone, Debug, PartialEq, Eq)]
 107pub struct GroupId {
 108    source: Arc<str>,
 109    id: usize,
 110}
 111
 112#[derive(Clone, Debug, PartialEq, Eq)]
 113pub struct Diagnostic {
 114    pub code: Option<String>,
 115    pub severity: DiagnosticSeverity,
 116    pub message: String,
 117    pub group_id: usize,
 118    pub is_valid: bool,
 119    pub is_primary: bool,
 120    pub is_disk_based: bool,
 121    pub is_unnecessary: bool,
 122}
 123
 124#[derive(Clone, Debug)]
 125pub struct Completion {
 126    pub old_range: Range<Anchor>,
 127    pub new_text: String,
 128    pub label: CodeLabel,
 129    pub lsp_completion: lsp::CompletionItem,
 130}
 131
 132#[derive(Clone, Debug)]
 133pub struct CodeAction {
 134    pub range: Range<Anchor>,
 135    pub lsp_action: lsp::CodeAction,
 136}
 137
 138#[derive(Clone, Debug, PartialEq, Eq)]
 139pub enum Operation {
 140    Buffer(text::Operation),
 141    UpdateDiagnostics {
 142        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 143        lamport_timestamp: clock::Lamport,
 144    },
 145    UpdateSelections {
 146        selections: Arc<[Selection<Anchor>]>,
 147        lamport_timestamp: clock::Lamport,
 148        line_mode: bool,
 149    },
 150    UpdateCompletionTriggers {
 151        triggers: Vec<String>,
 152        lamport_timestamp: clock::Lamport,
 153    },
 154}
 155
 156#[derive(Clone, Debug, PartialEq, Eq)]
 157pub enum Event {
 158    Operation(Operation),
 159    Edited,
 160    DirtyChanged,
 161    Saved,
 162    FileHandleChanged,
 163    Reloaded,
 164    Reparsed,
 165    DiagnosticsUpdated,
 166    Closed,
 167}
 168
 169pub trait File: Send + Sync {
 170    fn as_local(&self) -> Option<&dyn LocalFile>;
 171
 172    fn is_local(&self) -> bool {
 173        self.as_local().is_some()
 174    }
 175
 176    fn mtime(&self) -> SystemTime;
 177
 178    /// Returns the path of this file relative to the worktree's root directory.
 179    fn path(&self) -> &Arc<Path>;
 180
 181    /// Returns the path of this file relative to the worktree's parent directory (this means it
 182    /// includes the name of the worktree's root folder).
 183    fn full_path(&self, cx: &AppContext) -> PathBuf;
 184
 185    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 186    /// of its worktree, then this method will return the name of the worktree itself.
 187    fn file_name<'a>(&'a self, cx: &'a AppContext) -> &'a OsStr;
 188
 189    fn is_deleted(&self) -> bool;
 190
 191    fn save(
 192        &self,
 193        buffer_id: u64,
 194        text: Rope,
 195        version: clock::Global,
 196        line_ending: LineEnding,
 197        cx: &mut MutableAppContext,
 198    ) -> Task<Result<(clock::Global, String, SystemTime)>>;
 199
 200    fn as_any(&self) -> &dyn Any;
 201
 202    fn to_proto(&self) -> rpc::proto::File;
 203}
 204
 205pub trait LocalFile: File {
 206    /// Returns the absolute path of this file.
 207    fn abs_path(&self, cx: &AppContext) -> PathBuf;
 208
 209    fn load(&self, cx: &AppContext) -> Task<Result<String>>;
 210
 211    fn buffer_reloaded(
 212        &self,
 213        buffer_id: u64,
 214        version: &clock::Global,
 215        fingerprint: String,
 216        line_ending: LineEnding,
 217        mtime: SystemTime,
 218        cx: &mut MutableAppContext,
 219    );
 220}
 221
 222#[derive(Clone, Debug)]
 223pub enum AutoindentMode {
 224    /// Indent each line of inserted text.
 225    EachLine,
 226    /// Apply the same indentation adjustment to all of the lines
 227    /// in a given insertion.
 228    Block {
 229        /// The original indentation level of the first line of each
 230        /// insertion, if it has been copied.
 231        original_indent_columns: Vec<u32>,
 232    },
 233}
 234
 235#[derive(Clone)]
 236struct AutoindentRequest {
 237    before_edit: BufferSnapshot,
 238    entries: Vec<AutoindentRequestEntry>,
 239    indent_size: IndentSize,
 240    is_block_mode: bool,
 241}
 242
 243#[derive(Clone)]
 244struct AutoindentRequestEntry {
 245    /// A range of the buffer whose indentation should be adjusted.
 246    range: Range<Anchor>,
 247    /// Whether or not these lines should be considered brand new, for the
 248    /// purpose of auto-indent. When text is not new, its indentation will
 249    /// only be adjusted if the suggested indentation level has *changed*
 250    /// since the edit was made.
 251    first_line_is_new: bool,
 252    original_indent_column: Option<u32>,
 253}
 254
 255#[derive(Debug)]
 256struct IndentSuggestion {
 257    basis_row: u32,
 258    delta: Ordering,
 259}
 260
 261struct BufferChunkHighlights<'a> {
 262    captures: SyntaxMapCaptures<'a>,
 263    next_capture: Option<SyntaxMapCapture<'a>>,
 264    stack: Vec<(usize, HighlightId)>,
 265    highlight_maps: Vec<HighlightMap>,
 266}
 267
 268pub struct BufferChunks<'a> {
 269    range: Range<usize>,
 270    chunks: rope::Chunks<'a>,
 271    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 272    error_depth: usize,
 273    warning_depth: usize,
 274    information_depth: usize,
 275    hint_depth: usize,
 276    unnecessary_depth: usize,
 277    highlights: Option<BufferChunkHighlights<'a>>,
 278}
 279
 280#[derive(Clone, Copy, Debug, Default)]
 281pub struct Chunk<'a> {
 282    pub text: &'a str,
 283    pub syntax_highlight_id: Option<HighlightId>,
 284    pub highlight_style: Option<HighlightStyle>,
 285    pub diagnostic_severity: Option<DiagnosticSeverity>,
 286    pub is_unnecessary: bool,
 287}
 288
 289pub struct Diff {
 290    base_version: clock::Global,
 291    new_text: Arc<str>,
 292    changes: Vec<(ChangeTag, usize)>,
 293    line_ending: LineEnding,
 294    start_offset: usize,
 295}
 296
 297#[derive(Clone, Copy)]
 298pub(crate) struct DiagnosticEndpoint {
 299    offset: usize,
 300    is_start: bool,
 301    severity: DiagnosticSeverity,
 302    is_unnecessary: bool,
 303}
 304
 305#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 306pub enum CharKind {
 307    Punctuation,
 308    Whitespace,
 309    Word,
 310}
 311
 312impl CharKind {
 313    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 314        if treat_punctuation_as_word && self == CharKind::Punctuation {
 315            CharKind::Word
 316        } else {
 317            self
 318        }
 319    }
 320}
 321
 322impl Buffer {
 323    pub fn new<T: Into<String>>(
 324        replica_id: ReplicaId,
 325        base_text: T,
 326        cx: &mut ModelContext<Self>,
 327    ) -> Self {
 328        Self::build(
 329            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 330            None,
 331        )
 332    }
 333
 334    pub fn from_file<T: Into<String>>(
 335        replica_id: ReplicaId,
 336        base_text: T,
 337        file: Arc<dyn File>,
 338        cx: &mut ModelContext<Self>,
 339    ) -> Self {
 340        Self::build(
 341            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 342            Some(file),
 343        )
 344    }
 345
 346    pub fn from_proto(
 347        replica_id: ReplicaId,
 348        message: proto::BufferState,
 349        file: Option<Arc<dyn File>>,
 350    ) -> Result<Self> {
 351        let buffer = TextBuffer::new(replica_id, message.id, message.base_text);
 352        let mut this = Self::build(buffer, file);
 353        this.text.set_line_ending(proto::deserialize_line_ending(
 354            proto::LineEnding::from_i32(message.line_ending)
 355                .ok_or_else(|| anyhow!("missing line_ending"))?,
 356        ));
 357        Ok(this)
 358    }
 359
 360    pub fn to_proto(&self) -> proto::BufferState {
 361        proto::BufferState {
 362            id: self.remote_id(),
 363            file: self.file.as_ref().map(|f| f.to_proto()),
 364            base_text: self.base_text().to_string(),
 365            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 366        }
 367    }
 368
 369    pub fn serialize_ops(&self, cx: &AppContext) -> Task<Vec<proto::Operation>> {
 370        let mut operations = Vec::new();
 371        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 372        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 373            proto::serialize_operation(&Operation::UpdateSelections {
 374                selections: set.selections.clone(),
 375                lamport_timestamp: set.lamport_timestamp,
 376                line_mode: set.line_mode,
 377            })
 378        }));
 379        operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 380            diagnostics: self.diagnostics.iter().cloned().collect(),
 381            lamport_timestamp: self.diagnostics_timestamp,
 382        }));
 383        operations.push(proto::serialize_operation(
 384            &Operation::UpdateCompletionTriggers {
 385                triggers: self.completion_triggers.clone(),
 386                lamport_timestamp: self.completion_triggers_timestamp,
 387            },
 388        ));
 389
 390        let text_operations = self.text.operations().clone();
 391        cx.background().spawn(async move {
 392            operations.extend(
 393                text_operations
 394                    .iter()
 395                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 396            );
 397            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 398            operations
 399        })
 400    }
 401
 402    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 403        self.set_language(Some(language), cx);
 404        self
 405    }
 406
 407    fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>) -> Self {
 408        let saved_mtime = if let Some(file) = file.as_ref() {
 409            file.mtime()
 410        } else {
 411            UNIX_EPOCH
 412        };
 413
 414        Self {
 415            saved_mtime,
 416            saved_version: buffer.version(),
 417            saved_version_fingerprint: buffer.as_rope().fingerprint(),
 418            transaction_depth: 0,
 419            was_dirty_before_starting_transaction: None,
 420            text: buffer,
 421            file,
 422            syntax_map: Mutex::new(SyntaxMap::new()),
 423            parsing_in_background: false,
 424            parse_count: 0,
 425            sync_parse_timeout: Duration::from_millis(1),
 426            autoindent_requests: Default::default(),
 427            pending_autoindent: Default::default(),
 428            language: None,
 429            remote_selections: Default::default(),
 430            selections_update_count: 0,
 431            diagnostics: Default::default(),
 432            diagnostics_update_count: 0,
 433            diagnostics_timestamp: Default::default(),
 434            file_update_count: 0,
 435            completion_triggers: Default::default(),
 436            completion_triggers_timestamp: Default::default(),
 437            deferred_ops: OperationQueue::new(),
 438        }
 439    }
 440
 441    pub fn snapshot(&self) -> BufferSnapshot {
 442        let text = self.text.snapshot();
 443        let mut syntax_map = self.syntax_map.lock();
 444        syntax_map.interpolate(&text);
 445        let syntax = syntax_map.snapshot();
 446
 447        BufferSnapshot {
 448            text,
 449            syntax,
 450            file: self.file.clone(),
 451            remote_selections: self.remote_selections.clone(),
 452            diagnostics: self.diagnostics.clone(),
 453            diagnostics_update_count: self.diagnostics_update_count,
 454            file_update_count: self.file_update_count,
 455            language: self.language.clone(),
 456            parse_count: self.parse_count,
 457            selections_update_count: self.selections_update_count,
 458        }
 459    }
 460
 461    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 462        &self.text
 463    }
 464
 465    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 466        self.text.snapshot()
 467    }
 468
 469    pub fn file(&self) -> Option<&dyn File> {
 470        self.file.as_deref()
 471    }
 472
 473    pub fn save(
 474        &mut self,
 475        cx: &mut ModelContext<Self>,
 476    ) -> Task<Result<(clock::Global, String, SystemTime)>> {
 477        let file = if let Some(file) = self.file.as_ref() {
 478            file
 479        } else {
 480            return Task::ready(Err(anyhow!("buffer has no file")));
 481        };
 482        let text = self.as_rope().clone();
 483        let version = self.version();
 484        let save = file.save(
 485            self.remote_id(),
 486            text,
 487            version,
 488            self.line_ending(),
 489            cx.as_mut(),
 490        );
 491        cx.spawn(|this, mut cx| async move {
 492            let (version, fingerprint, mtime) = save.await?;
 493            this.update(&mut cx, |this, cx| {
 494                this.did_save(version.clone(), fingerprint.clone(), mtime, None, cx);
 495            });
 496            Ok((version, fingerprint, mtime))
 497        })
 498    }
 499
 500    pub fn saved_version(&self) -> &clock::Global {
 501        &self.saved_version
 502    }
 503
 504    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 505        self.syntax_map.lock().clear();
 506        self.language = language;
 507        self.reparse(cx);
 508    }
 509
 510    pub fn set_language_registry(&mut self, language_registry: Arc<LanguageRegistry>) {
 511        self.syntax_map
 512            .lock()
 513            .set_language_registry(language_registry);
 514    }
 515
 516    pub fn did_save(
 517        &mut self,
 518        version: clock::Global,
 519        fingerprint: String,
 520        mtime: SystemTime,
 521        new_file: Option<Arc<dyn File>>,
 522        cx: &mut ModelContext<Self>,
 523    ) {
 524        self.saved_version = version;
 525        self.saved_version_fingerprint = fingerprint;
 526        self.saved_mtime = mtime;
 527        if let Some(new_file) = new_file {
 528            self.file = Some(new_file);
 529            self.file_update_count += 1;
 530        }
 531        cx.emit(Event::Saved);
 532        cx.notify();
 533    }
 534
 535    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 536        cx.spawn(|this, mut cx| async move {
 537            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 538                let file = this.file.as_ref()?.as_local()?;
 539                Some((file.mtime(), file.load(cx)))
 540            }) {
 541                let new_text = new_text.await?;
 542                let diff = this
 543                    .read_with(&cx, |this, cx| this.diff(new_text, cx))
 544                    .await;
 545                this.update(&mut cx, |this, cx| {
 546                    if let Some(transaction) = this.apply_diff(diff, cx).cloned() {
 547                        this.did_reload(
 548                            this.version(),
 549                            this.as_rope().fingerprint(),
 550                            this.line_ending(),
 551                            new_mtime,
 552                            cx,
 553                        );
 554                        Ok(Some(transaction))
 555                    } else {
 556                        Ok(None)
 557                    }
 558                })
 559            } else {
 560                Ok(None)
 561            }
 562        })
 563    }
 564
 565    pub fn did_reload(
 566        &mut self,
 567        version: clock::Global,
 568        fingerprint: String,
 569        line_ending: LineEnding,
 570        mtime: SystemTime,
 571        cx: &mut ModelContext<Self>,
 572    ) {
 573        self.saved_version = version;
 574        self.saved_version_fingerprint = fingerprint;
 575        self.text.set_line_ending(line_ending);
 576        self.saved_mtime = mtime;
 577        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 578            file.buffer_reloaded(
 579                self.remote_id(),
 580                &self.saved_version,
 581                self.saved_version_fingerprint.clone(),
 582                self.line_ending(),
 583                self.saved_mtime,
 584                cx,
 585            );
 586        }
 587        cx.emit(Event::Reloaded);
 588        cx.notify();
 589    }
 590
 591    pub fn file_updated(
 592        &mut self,
 593        new_file: Arc<dyn File>,
 594        cx: &mut ModelContext<Self>,
 595    ) -> Task<()> {
 596        let old_file = if let Some(file) = self.file.as_ref() {
 597            file
 598        } else {
 599            return Task::ready(());
 600        };
 601        let mut file_changed = false;
 602        let mut task = Task::ready(());
 603
 604        if new_file.path() != old_file.path() {
 605            file_changed = true;
 606        }
 607
 608        if new_file.is_deleted() {
 609            if !old_file.is_deleted() {
 610                file_changed = true;
 611                if !self.is_dirty() {
 612                    cx.emit(Event::DirtyChanged);
 613                }
 614            }
 615        } else {
 616            let new_mtime = new_file.mtime();
 617            if new_mtime != old_file.mtime() {
 618                file_changed = true;
 619
 620                if !self.is_dirty() {
 621                    let reload = self.reload(cx).log_err().map(drop);
 622                    task = cx.foreground().spawn(reload);
 623                }
 624            }
 625        }
 626
 627        if file_changed {
 628            self.file_update_count += 1;
 629            cx.emit(Event::FileHandleChanged);
 630            cx.notify();
 631        }
 632        self.file = Some(new_file);
 633        task
 634    }
 635
 636    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 637        cx.emit(Event::Closed);
 638    }
 639
 640    pub fn language(&self) -> Option<&Arc<Language>> {
 641        self.language.as_ref()
 642    }
 643
 644    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
 645        let offset = position.to_offset(self);
 646        self.syntax_map
 647            .lock()
 648            .layers_for_range(offset..offset, &self.text)
 649            .last()
 650            .map(|info| info.language.clone())
 651    }
 652
 653    pub fn parse_count(&self) -> usize {
 654        self.parse_count
 655    }
 656
 657    pub fn selections_update_count(&self) -> usize {
 658        self.selections_update_count
 659    }
 660
 661    pub fn diagnostics_update_count(&self) -> usize {
 662        self.diagnostics_update_count
 663    }
 664
 665    pub fn file_update_count(&self) -> usize {
 666        self.file_update_count
 667    }
 668
 669    #[cfg(any(test, feature = "test-support"))]
 670    pub fn is_parsing(&self) -> bool {
 671        self.parsing_in_background
 672    }
 673
 674    #[cfg(test)]
 675    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 676        self.sync_parse_timeout = timeout;
 677    }
 678
 679    fn reparse(&mut self, cx: &mut ModelContext<Self>) {
 680        if self.parsing_in_background {
 681            return;
 682        }
 683        let language = if let Some(language) = self.language.clone() {
 684            language
 685        } else {
 686            return;
 687        };
 688
 689        let text = self.text_snapshot();
 690        let parsed_version = self.version();
 691
 692        let mut syntax_map = self.syntax_map.lock();
 693        syntax_map.interpolate(&text);
 694        let language_registry = syntax_map.language_registry();
 695        let mut syntax_snapshot = syntax_map.snapshot();
 696        let syntax_map_version = syntax_map.parsed_version();
 697        drop(syntax_map);
 698
 699        let parse_task = cx.background().spawn({
 700            let language = language.clone();
 701            async move {
 702                syntax_snapshot.reparse(&syntax_map_version, &text, language_registry, language);
 703                syntax_snapshot
 704            }
 705        });
 706
 707        match cx
 708            .background()
 709            .block_with_timeout(self.sync_parse_timeout, parse_task)
 710        {
 711            Ok(new_syntax_snapshot) => {
 712                self.did_finish_parsing(new_syntax_snapshot, parsed_version, cx);
 713                return;
 714            }
 715            Err(parse_task) => {
 716                self.parsing_in_background = true;
 717                cx.spawn(move |this, mut cx| async move {
 718                    let new_syntax_map = parse_task.await;
 719                    this.update(&mut cx, move |this, cx| {
 720                        let grammar_changed =
 721                            this.language.as_ref().map_or(true, |current_language| {
 722                                !Arc::ptr_eq(&language, current_language)
 723                            });
 724                        let parse_again =
 725                            this.version.changed_since(&parsed_version) || grammar_changed;
 726                        this.did_finish_parsing(new_syntax_map, parsed_version, cx);
 727                        this.parsing_in_background = false;
 728                        if parse_again {
 729                            this.reparse(cx);
 730                        }
 731                    });
 732                })
 733                .detach();
 734            }
 735        }
 736    }
 737
 738    fn did_finish_parsing(
 739        &mut self,
 740        syntax_snapshot: SyntaxSnapshot,
 741        version: clock::Global,
 742        cx: &mut ModelContext<Self>,
 743    ) {
 744        self.parse_count += 1;
 745        self.syntax_map.lock().did_parse(syntax_snapshot, version);
 746        self.request_autoindent(cx);
 747        cx.emit(Event::Reparsed);
 748        cx.notify();
 749    }
 750
 751    pub fn update_diagnostics(&mut self, diagnostics: DiagnosticSet, cx: &mut ModelContext<Self>) {
 752        let lamport_timestamp = self.text.lamport_clock.tick();
 753        let op = Operation::UpdateDiagnostics {
 754            diagnostics: diagnostics.iter().cloned().collect(),
 755            lamport_timestamp,
 756        };
 757        self.apply_diagnostic_update(diagnostics, lamport_timestamp, cx);
 758        self.send_operation(op, cx);
 759    }
 760
 761    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 762        if let Some(indent_sizes) = self.compute_autoindents() {
 763            let indent_sizes = cx.background().spawn(indent_sizes);
 764            match cx
 765                .background()
 766                .block_with_timeout(Duration::from_micros(500), indent_sizes)
 767            {
 768                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
 769                Err(indent_sizes) => {
 770                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 771                        let indent_sizes = indent_sizes.await;
 772                        this.update(&mut cx, |this, cx| {
 773                            this.apply_autoindents(indent_sizes, cx);
 774                        });
 775                    }));
 776                }
 777            }
 778        }
 779    }
 780
 781    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
 782        let max_rows_between_yields = 100;
 783        let snapshot = self.snapshot();
 784        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
 785            return None;
 786        }
 787
 788        let autoindent_requests = self.autoindent_requests.clone();
 789        Some(async move {
 790            let mut indent_sizes = BTreeMap::new();
 791            for request in autoindent_requests {
 792                // Resolve each edited range to its row in the current buffer and in the
 793                // buffer before this batch of edits.
 794                let mut row_ranges = Vec::new();
 795                let mut old_to_new_rows = BTreeMap::new();
 796                for entry in &request.entries {
 797                    let position = entry.range.start;
 798                    let new_row = position.to_point(&snapshot).row;
 799                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
 800                    if !entry.first_line_is_new {
 801                        let old_row = position.to_point(&request.before_edit).row;
 802                        old_to_new_rows.insert(old_row, new_row);
 803                    }
 804                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
 805                }
 806
 807                // Build a map containing the suggested indentation for each of the edited lines
 808                // with respect to the state of the buffer before these edits. This map is keyed
 809                // by the rows for these lines in the current state of the buffer.
 810                let mut old_suggestions = BTreeMap::<u32, IndentSize>::default();
 811                let old_edited_ranges =
 812                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 813                for old_edited_range in old_edited_ranges {
 814                    let suggestions = request
 815                        .before_edit
 816                        .suggest_autoindents(old_edited_range.clone())
 817                        .into_iter()
 818                        .flatten();
 819                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 820                        if let Some(suggestion) = suggestion {
 821                            let suggested_indent = old_to_new_rows
 822                                .get(&suggestion.basis_row)
 823                                .and_then(|from_row| old_suggestions.get(from_row).copied())
 824                                .unwrap_or_else(|| {
 825                                    request
 826                                        .before_edit
 827                                        .indent_size_for_line(suggestion.basis_row)
 828                                })
 829                                .with_delta(suggestion.delta, request.indent_size);
 830                            old_suggestions
 831                                .insert(*old_to_new_rows.get(&old_row).unwrap(), suggested_indent);
 832                        }
 833                    }
 834                    yield_now().await;
 835                }
 836
 837                // In block mode, only compute indentation suggestions for the first line
 838                // of each insertion. Otherwise, compute suggestions for every inserted line.
 839                let new_edited_row_ranges = contiguous_ranges(
 840                    row_ranges.iter().flat_map(|(range, _)| {
 841                        if request.is_block_mode {
 842                            range.start..range.start + 1
 843                        } else {
 844                            range.clone()
 845                        }
 846                    }),
 847                    max_rows_between_yields,
 848                );
 849
 850                // Compute new suggestions for each line, but only include them in the result
 851                // if they differ from the old suggestion for that line.
 852                for new_edited_row_range in new_edited_row_ranges {
 853                    let suggestions = snapshot
 854                        .suggest_autoindents(new_edited_row_range.clone())
 855                        .into_iter()
 856                        .flatten();
 857                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
 858                        if let Some(suggestion) = suggestion {
 859                            let suggested_indent = indent_sizes
 860                                .get(&suggestion.basis_row)
 861                                .copied()
 862                                .unwrap_or_else(|| {
 863                                    snapshot.indent_size_for_line(suggestion.basis_row)
 864                                })
 865                                .with_delta(suggestion.delta, request.indent_size);
 866                            if old_suggestions
 867                                .get(&new_row)
 868                                .map_or(true, |old_indentation| {
 869                                    suggested_indent != *old_indentation
 870                                })
 871                            {
 872                                indent_sizes.insert(new_row, suggested_indent);
 873                            }
 874                        }
 875                    }
 876                    yield_now().await;
 877                }
 878
 879                // For each block of inserted text, adjust the indentation of the remaining
 880                // lines of the block by the same amount as the first line was adjusted.
 881                if request.is_block_mode {
 882                    for (row_range, original_indent_column) in
 883                        row_ranges
 884                            .into_iter()
 885                            .filter_map(|(range, original_indent_column)| {
 886                                if range.len() > 1 {
 887                                    Some((range, original_indent_column?))
 888                                } else {
 889                                    None
 890                                }
 891                            })
 892                    {
 893                        let new_indent = indent_sizes
 894                            .get(&row_range.start)
 895                            .copied()
 896                            .unwrap_or_else(|| snapshot.indent_size_for_line(row_range.start));
 897                        let delta = new_indent.len as i64 - original_indent_column as i64;
 898                        if delta != 0 {
 899                            for row in row_range.skip(1) {
 900                                indent_sizes.entry(row).or_insert_with(|| {
 901                                    let mut size = snapshot.indent_size_for_line(row);
 902                                    if size.kind == new_indent.kind {
 903                                        match delta.cmp(&0) {
 904                                            Ordering::Greater => size.len += delta as u32,
 905                                            Ordering::Less => {
 906                                                size.len = size.len.saturating_sub(-delta as u32)
 907                                            }
 908                                            Ordering::Equal => {}
 909                                        }
 910                                    }
 911                                    size
 912                                });
 913                            }
 914                        }
 915                    }
 916                }
 917            }
 918
 919            indent_sizes
 920        })
 921    }
 922
 923    fn apply_autoindents(
 924        &mut self,
 925        indent_sizes: BTreeMap<u32, IndentSize>,
 926        cx: &mut ModelContext<Self>,
 927    ) {
 928        self.autoindent_requests.clear();
 929
 930        let edits: Vec<_> = indent_sizes
 931            .into_iter()
 932            .filter_map(|(row, indent_size)| {
 933                let current_size = indent_size_for_line(self, row);
 934                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
 935            })
 936            .collect();
 937
 938        self.edit(edits, None, cx);
 939    }
 940
 941    pub fn edit_for_indent_size_adjustment(
 942        row: u32,
 943        current_size: IndentSize,
 944        new_size: IndentSize,
 945    ) -> Option<(Range<Point>, String)> {
 946        if new_size.kind != current_size.kind && current_size.len > 0 {
 947            return None;
 948        }
 949
 950        match new_size.len.cmp(&current_size.len) {
 951            Ordering::Greater => {
 952                let point = Point::new(row, 0);
 953                Some((
 954                    point..point,
 955                    iter::repeat(new_size.char())
 956                        .take((new_size.len - current_size.len) as usize)
 957                        .collect::<String>(),
 958                ))
 959            }
 960
 961            Ordering::Less => Some((
 962                Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
 963                String::new(),
 964            )),
 965
 966            Ordering::Equal => None,
 967        }
 968    }
 969
 970    pub fn diff(&self, mut new_text: String, cx: &AppContext) -> Task<Diff> {
 971        let old_text = self.as_rope().clone();
 972        let base_version = self.version();
 973        cx.background().spawn(async move {
 974            let old_text = old_text.to_string();
 975            let line_ending = LineEnding::detect(&new_text);
 976            LineEnding::normalize(&mut new_text);
 977            let changes = TextDiff::from_chars(old_text.as_str(), new_text.as_str())
 978                .iter_all_changes()
 979                .map(|c| (c.tag(), c.value().len()))
 980                .collect::<Vec<_>>();
 981            Diff {
 982                base_version,
 983                new_text: new_text.into(),
 984                changes,
 985                line_ending,
 986                start_offset: 0,
 987            }
 988        })
 989    }
 990
 991    pub fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> Option<&Transaction> {
 992        if self.version == diff.base_version {
 993            self.finalize_last_transaction();
 994            self.start_transaction();
 995            self.text.set_line_ending(diff.line_ending);
 996            let mut offset = diff.start_offset;
 997            for (tag, len) in diff.changes {
 998                let range = offset..(offset + len);
 999                match tag {
1000                    ChangeTag::Equal => offset += len,
1001                    ChangeTag::Delete => {
1002                        self.edit([(range, "")], None, cx);
1003                    }
1004                    ChangeTag::Insert => {
1005                        self.edit(
1006                            [(
1007                                offset..offset,
1008                                &diff.new_text[range.start - diff.start_offset
1009                                    ..range.end - diff.start_offset],
1010                            )],
1011                            None,
1012                            cx,
1013                        );
1014                        offset += len;
1015                    }
1016                }
1017            }
1018            if self.end_transaction(cx).is_some() {
1019                self.finalize_last_transaction()
1020            } else {
1021                None
1022            }
1023        } else {
1024            None
1025        }
1026    }
1027
1028    pub fn is_dirty(&self) -> bool {
1029        self.saved_version_fingerprint != self.as_rope().fingerprint()
1030            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1031    }
1032
1033    pub fn has_conflict(&self) -> bool {
1034        self.saved_version_fingerprint != self.as_rope().fingerprint()
1035            && self
1036                .file
1037                .as_ref()
1038                .map_or(false, |file| file.mtime() > self.saved_mtime)
1039    }
1040
1041    pub fn subscribe(&mut self) -> Subscription {
1042        self.text.subscribe()
1043    }
1044
1045    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1046        self.start_transaction_at(Instant::now())
1047    }
1048
1049    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1050        self.transaction_depth += 1;
1051        if self.was_dirty_before_starting_transaction.is_none() {
1052            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1053        }
1054        self.text.start_transaction_at(now)
1055    }
1056
1057    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1058        self.end_transaction_at(Instant::now(), cx)
1059    }
1060
1061    pub fn end_transaction_at(
1062        &mut self,
1063        now: Instant,
1064        cx: &mut ModelContext<Self>,
1065    ) -> Option<TransactionId> {
1066        assert!(self.transaction_depth > 0);
1067        self.transaction_depth -= 1;
1068        let was_dirty = if self.transaction_depth == 0 {
1069            self.was_dirty_before_starting_transaction.take().unwrap()
1070        } else {
1071            false
1072        };
1073        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1074            self.did_edit(&start_version, was_dirty, cx);
1075            Some(transaction_id)
1076        } else {
1077            None
1078        }
1079    }
1080
1081    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1082        self.text.push_transaction(transaction, now);
1083    }
1084
1085    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1086        self.text.finalize_last_transaction()
1087    }
1088
1089    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1090        self.text.group_until_transaction(transaction_id);
1091    }
1092
1093    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1094        self.text.forget_transaction(transaction_id);
1095    }
1096
1097    pub fn wait_for_edits(
1098        &mut self,
1099        edit_ids: impl IntoIterator<Item = clock::Local>,
1100    ) -> impl Future<Output = ()> {
1101        self.text.wait_for_edits(edit_ids)
1102    }
1103
1104    pub fn wait_for_anchors<'a>(
1105        &mut self,
1106        anchors: impl IntoIterator<Item = &'a Anchor>,
1107    ) -> impl Future<Output = ()> {
1108        self.text.wait_for_anchors(anchors)
1109    }
1110
1111    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = ()> {
1112        self.text.wait_for_version(version)
1113    }
1114
1115    pub fn set_active_selections(
1116        &mut self,
1117        selections: Arc<[Selection<Anchor>]>,
1118        line_mode: bool,
1119        cx: &mut ModelContext<Self>,
1120    ) {
1121        let lamport_timestamp = self.text.lamport_clock.tick();
1122        self.remote_selections.insert(
1123            self.text.replica_id(),
1124            SelectionSet {
1125                selections: selections.clone(),
1126                lamport_timestamp,
1127                line_mode,
1128            },
1129        );
1130        self.send_operation(
1131            Operation::UpdateSelections {
1132                selections,
1133                line_mode,
1134                lamport_timestamp,
1135            },
1136            cx,
1137        );
1138    }
1139
1140    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1141        self.set_active_selections(Arc::from([]), false, cx);
1142    }
1143
1144    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1145    where
1146        T: Into<Arc<str>>,
1147    {
1148        self.edit([(0..self.len(), text)], None, cx)
1149    }
1150
1151    pub fn edit<I, S, T>(
1152        &mut self,
1153        edits_iter: I,
1154        autoindent_mode: Option<AutoindentMode>,
1155        cx: &mut ModelContext<Self>,
1156    ) -> Option<clock::Local>
1157    where
1158        I: IntoIterator<Item = (Range<S>, T)>,
1159        S: ToOffset,
1160        T: Into<Arc<str>>,
1161    {
1162        // Skip invalid edits and coalesce contiguous ones.
1163        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1164        for (range, new_text) in edits_iter {
1165            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
1166            if range.start > range.end {
1167                mem::swap(&mut range.start, &mut range.end);
1168            }
1169            let new_text = new_text.into();
1170            if !new_text.is_empty() || !range.is_empty() {
1171                if let Some((prev_range, prev_text)) = edits.last_mut() {
1172                    if prev_range.end >= range.start {
1173                        prev_range.end = cmp::max(prev_range.end, range.end);
1174                        *prev_text = format!("{prev_text}{new_text}").into();
1175                    } else {
1176                        edits.push((range, new_text));
1177                    }
1178                } else {
1179                    edits.push((range, new_text));
1180                }
1181            }
1182        }
1183        if edits.is_empty() {
1184            return None;
1185        }
1186
1187        self.start_transaction();
1188        self.pending_autoindent.take();
1189        let autoindent_request = autoindent_mode
1190            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
1191
1192        let edit_operation = self.text.edit(edits.iter().cloned());
1193        let edit_id = edit_operation.local_timestamp();
1194
1195        if let Some((before_edit, mode)) = autoindent_request {
1196            let indent_size = before_edit.single_indent_size(cx);
1197            let (start_columns, is_block_mode) = match mode {
1198                AutoindentMode::Block {
1199                    original_indent_columns: start_columns,
1200                } => (start_columns, true),
1201                AutoindentMode::EachLine => (Default::default(), false),
1202            };
1203
1204            let mut delta = 0isize;
1205            let entries = edits
1206                .into_iter()
1207                .enumerate()
1208                .zip(&edit_operation.as_edit().unwrap().new_text)
1209                .map(|((ix, (range, _)), new_text)| {
1210                    let new_text_len = new_text.len();
1211                    let old_start = range.start.to_point(&before_edit);
1212                    let new_start = (delta + range.start as isize) as usize;
1213                    delta += new_text_len as isize - (range.end as isize - range.start as isize);
1214
1215                    let mut range_of_insertion_to_indent = 0..new_text_len;
1216                    let mut first_line_is_new = false;
1217                    let mut start_column = None;
1218
1219                    // When inserting an entire line at the beginning of an existing line,
1220                    // treat the insertion as new.
1221                    if new_text.contains('\n')
1222                        && old_start.column <= before_edit.indent_size_for_line(old_start.row).len
1223                    {
1224                        first_line_is_new = true;
1225                    }
1226
1227                    // When inserting text starting with a newline, avoid auto-indenting the
1228                    // previous line.
1229                    if new_text[range_of_insertion_to_indent.clone()].starts_with('\n') {
1230                        range_of_insertion_to_indent.start += 1;
1231                        first_line_is_new = true;
1232                    }
1233
1234                    // Avoid auto-indenting after the insertion.
1235                    if is_block_mode {
1236                        start_column = start_columns.get(ix).copied();
1237                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
1238                            range_of_insertion_to_indent.end -= 1;
1239                        }
1240                    }
1241
1242                    AutoindentRequestEntry {
1243                        first_line_is_new,
1244                        original_indent_column: start_column,
1245                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
1246                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
1247                    }
1248                })
1249                .collect();
1250
1251            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1252                before_edit,
1253                entries,
1254                indent_size,
1255                is_block_mode,
1256            }));
1257        }
1258
1259        self.end_transaction(cx);
1260        self.send_operation(Operation::Buffer(edit_operation), cx);
1261        Some(edit_id)
1262    }
1263
1264    fn did_edit(
1265        &mut self,
1266        old_version: &clock::Global,
1267        was_dirty: bool,
1268        cx: &mut ModelContext<Self>,
1269    ) {
1270        if self.edits_since::<usize>(old_version).next().is_none() {
1271            return;
1272        }
1273
1274        self.reparse(cx);
1275
1276        cx.emit(Event::Edited);
1277        if was_dirty != self.is_dirty() {
1278            cx.emit(Event::DirtyChanged);
1279        }
1280        cx.notify();
1281    }
1282
1283    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1284        &mut self,
1285        ops: I,
1286        cx: &mut ModelContext<Self>,
1287    ) -> Result<()> {
1288        self.pending_autoindent.take();
1289        let was_dirty = self.is_dirty();
1290        let old_version = self.version.clone();
1291        let mut deferred_ops = Vec::new();
1292        let buffer_ops = ops
1293            .into_iter()
1294            .filter_map(|op| match op {
1295                Operation::Buffer(op) => Some(op),
1296                _ => {
1297                    if self.can_apply_op(&op) {
1298                        self.apply_op(op, cx);
1299                    } else {
1300                        deferred_ops.push(op);
1301                    }
1302                    None
1303                }
1304            })
1305            .collect::<Vec<_>>();
1306        self.text.apply_ops(buffer_ops)?;
1307        self.deferred_ops.insert(deferred_ops);
1308        self.flush_deferred_ops(cx);
1309        self.did_edit(&old_version, was_dirty, cx);
1310        // Notify independently of whether the buffer was edited as the operations could include a
1311        // selection update.
1312        cx.notify();
1313        Ok(())
1314    }
1315
1316    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1317        let mut deferred_ops = Vec::new();
1318        for op in self.deferred_ops.drain().iter().cloned() {
1319            if self.can_apply_op(&op) {
1320                self.apply_op(op, cx);
1321            } else {
1322                deferred_ops.push(op);
1323            }
1324        }
1325        self.deferred_ops.insert(deferred_ops);
1326    }
1327
1328    fn can_apply_op(&self, operation: &Operation) -> bool {
1329        match operation {
1330            Operation::Buffer(_) => {
1331                unreachable!("buffer operations should never be applied at this layer")
1332            }
1333            Operation::UpdateDiagnostics {
1334                diagnostics: diagnostic_set,
1335                ..
1336            } => diagnostic_set.iter().all(|diagnostic| {
1337                self.text.can_resolve(&diagnostic.range.start)
1338                    && self.text.can_resolve(&diagnostic.range.end)
1339            }),
1340            Operation::UpdateSelections { selections, .. } => selections
1341                .iter()
1342                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1343            Operation::UpdateCompletionTriggers { .. } => true,
1344        }
1345    }
1346
1347    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1348        match operation {
1349            Operation::Buffer(_) => {
1350                unreachable!("buffer operations should never be applied at this layer")
1351            }
1352            Operation::UpdateDiagnostics {
1353                diagnostics: diagnostic_set,
1354                lamport_timestamp,
1355            } => {
1356                let snapshot = self.snapshot();
1357                self.apply_diagnostic_update(
1358                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1359                    lamport_timestamp,
1360                    cx,
1361                );
1362            }
1363            Operation::UpdateSelections {
1364                selections,
1365                lamport_timestamp,
1366                line_mode,
1367            } => {
1368                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1369                    if set.lamport_timestamp > lamport_timestamp {
1370                        return;
1371                    }
1372                }
1373
1374                self.remote_selections.insert(
1375                    lamport_timestamp.replica_id,
1376                    SelectionSet {
1377                        selections,
1378                        lamport_timestamp,
1379                        line_mode,
1380                    },
1381                );
1382                self.text.lamport_clock.observe(lamport_timestamp);
1383                self.selections_update_count += 1;
1384            }
1385            Operation::UpdateCompletionTriggers {
1386                triggers,
1387                lamport_timestamp,
1388            } => {
1389                self.completion_triggers = triggers;
1390                self.text.lamport_clock.observe(lamport_timestamp);
1391            }
1392        }
1393    }
1394
1395    fn apply_diagnostic_update(
1396        &mut self,
1397        diagnostics: DiagnosticSet,
1398        lamport_timestamp: clock::Lamport,
1399        cx: &mut ModelContext<Self>,
1400    ) {
1401        if lamport_timestamp > self.diagnostics_timestamp {
1402            self.diagnostics = diagnostics;
1403            self.diagnostics_timestamp = lamport_timestamp;
1404            self.diagnostics_update_count += 1;
1405            self.text.lamport_clock.observe(lamport_timestamp);
1406            cx.notify();
1407            cx.emit(Event::DiagnosticsUpdated);
1408        }
1409    }
1410
1411    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1412        cx.emit(Event::Operation(operation));
1413    }
1414
1415    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1416        self.remote_selections.remove(&replica_id);
1417        cx.notify();
1418    }
1419
1420    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1421        let was_dirty = self.is_dirty();
1422        let old_version = self.version.clone();
1423
1424        if let Some((transaction_id, operation)) = self.text.undo() {
1425            self.send_operation(Operation::Buffer(operation), cx);
1426            self.did_edit(&old_version, was_dirty, cx);
1427            Some(transaction_id)
1428        } else {
1429            None
1430        }
1431    }
1432
1433    pub fn undo_to_transaction(
1434        &mut self,
1435        transaction_id: TransactionId,
1436        cx: &mut ModelContext<Self>,
1437    ) -> bool {
1438        let was_dirty = self.is_dirty();
1439        let old_version = self.version.clone();
1440
1441        let operations = self.text.undo_to_transaction(transaction_id);
1442        let undone = !operations.is_empty();
1443        for operation in operations {
1444            self.send_operation(Operation::Buffer(operation), cx);
1445        }
1446        if undone {
1447            self.did_edit(&old_version, was_dirty, cx)
1448        }
1449        undone
1450    }
1451
1452    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1453        let was_dirty = self.is_dirty();
1454        let old_version = self.version.clone();
1455
1456        if let Some((transaction_id, operation)) = self.text.redo() {
1457            self.send_operation(Operation::Buffer(operation), cx);
1458            self.did_edit(&old_version, was_dirty, cx);
1459            Some(transaction_id)
1460        } else {
1461            None
1462        }
1463    }
1464
1465    pub fn redo_to_transaction(
1466        &mut self,
1467        transaction_id: TransactionId,
1468        cx: &mut ModelContext<Self>,
1469    ) -> bool {
1470        let was_dirty = self.is_dirty();
1471        let old_version = self.version.clone();
1472
1473        let operations = self.text.redo_to_transaction(transaction_id);
1474        let redone = !operations.is_empty();
1475        for operation in operations {
1476            self.send_operation(Operation::Buffer(operation), cx);
1477        }
1478        if redone {
1479            self.did_edit(&old_version, was_dirty, cx)
1480        }
1481        redone
1482    }
1483
1484    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1485        self.completion_triggers = triggers.clone();
1486        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
1487        self.send_operation(
1488            Operation::UpdateCompletionTriggers {
1489                triggers,
1490                lamport_timestamp: self.completion_triggers_timestamp,
1491            },
1492            cx,
1493        );
1494        cx.notify();
1495    }
1496
1497    pub fn completion_triggers(&self) -> &[String] {
1498        &self.completion_triggers
1499    }
1500}
1501
1502#[cfg(any(test, feature = "test-support"))]
1503impl Buffer {
1504    pub fn set_group_interval(&mut self, group_interval: Duration) {
1505        self.text.set_group_interval(group_interval);
1506    }
1507
1508    pub fn randomly_edit<T>(
1509        &mut self,
1510        rng: &mut T,
1511        old_range_count: usize,
1512        cx: &mut ModelContext<Self>,
1513    ) where
1514        T: rand::Rng,
1515    {
1516        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
1517        let mut last_end = None;
1518        for _ in 0..old_range_count {
1519            if last_end.map_or(false, |last_end| last_end >= self.len()) {
1520                break;
1521            }
1522
1523            let new_start = last_end.map_or(0, |last_end| last_end + 1);
1524            let mut range = self.random_byte_range(new_start, rng);
1525            if rng.gen_bool(0.2) {
1526                mem::swap(&mut range.start, &mut range.end);
1527            }
1528            last_end = Some(range.end);
1529
1530            let new_text_len = rng.gen_range(0..10);
1531            let new_text: String = crate::random_char_iter::RandomCharIter::new(&mut *rng)
1532                .take(new_text_len)
1533                .collect();
1534
1535            edits.push((range, new_text));
1536        }
1537        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
1538        self.edit(edits, None, cx);
1539    }
1540
1541    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1542        let was_dirty = self.is_dirty();
1543        let old_version = self.version.clone();
1544
1545        let ops = self.text.randomly_undo_redo(rng);
1546        if !ops.is_empty() {
1547            for op in ops {
1548                self.send_operation(Operation::Buffer(op), cx);
1549                self.did_edit(&old_version, was_dirty, cx);
1550            }
1551        }
1552    }
1553}
1554
1555impl Entity for Buffer {
1556    type Event = Event;
1557}
1558
1559impl Deref for Buffer {
1560    type Target = TextBuffer;
1561
1562    fn deref(&self) -> &Self::Target {
1563        &self.text
1564    }
1565}
1566
1567impl BufferSnapshot {
1568    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
1569        indent_size_for_line(self, row)
1570    }
1571
1572    pub fn single_indent_size(&self, cx: &AppContext) -> IndentSize {
1573        let language_name = self.language().map(|language| language.name());
1574        let settings = cx.global::<Settings>();
1575        if settings.hard_tabs(language_name.as_deref()) {
1576            IndentSize::tab()
1577        } else {
1578            IndentSize::spaces(settings.tab_size(language_name.as_deref()).get())
1579        }
1580    }
1581
1582    pub fn suggested_indents(
1583        &self,
1584        rows: impl Iterator<Item = u32>,
1585        single_indent_size: IndentSize,
1586    ) -> BTreeMap<u32, IndentSize> {
1587        let mut result = BTreeMap::new();
1588
1589        for row_range in contiguous_ranges(rows, 10) {
1590            let suggestions = match self.suggest_autoindents(row_range.clone()) {
1591                Some(suggestions) => suggestions,
1592                _ => break,
1593            };
1594
1595            for (row, suggestion) in row_range.zip(suggestions) {
1596                let indent_size = if let Some(suggestion) = suggestion {
1597                    result
1598                        .get(&suggestion.basis_row)
1599                        .copied()
1600                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
1601                        .with_delta(suggestion.delta, single_indent_size)
1602                } else {
1603                    self.indent_size_for_line(row)
1604                };
1605
1606                result.insert(row, indent_size);
1607            }
1608        }
1609
1610        result
1611    }
1612
1613    fn suggest_autoindents(
1614        &self,
1615        row_range: Range<u32>,
1616    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
1617        let config = &self.language.as_ref()?.config;
1618        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1619
1620        // Find the suggested indentation ranges based on the syntax tree.
1621        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
1622        let end = Point::new(row_range.end, 0);
1623        let range = (start..end).to_offset(&self.text);
1624        let mut matches = self.syntax.matches(range, &self.text, |grammar| {
1625            Some(&grammar.indents_config.as_ref()?.query)
1626        });
1627        let indent_configs = matches
1628            .grammars()
1629            .iter()
1630            .map(|grammar| grammar.indents_config.as_ref().unwrap())
1631            .collect::<Vec<_>>();
1632
1633        let mut indent_ranges = Vec::<Range<Point>>::new();
1634        while let Some(mat) = matches.peek() {
1635            let mut start: Option<Point> = None;
1636            let mut end: Option<Point> = None;
1637
1638            let config = &indent_configs[mat.grammar_index];
1639            for capture in mat.captures {
1640                if capture.index == config.indent_capture_ix {
1641                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1642                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1643                } else if Some(capture.index) == config.start_capture_ix {
1644                    start = Some(Point::from_ts_point(capture.node.end_position()));
1645                } else if Some(capture.index) == config.end_capture_ix {
1646                    end = Some(Point::from_ts_point(capture.node.start_position()));
1647                }
1648            }
1649
1650            matches.advance();
1651            if let Some((start, end)) = start.zip(end) {
1652                if start.row == end.row {
1653                    continue;
1654                }
1655
1656                let range = start..end;
1657                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
1658                    Err(ix) => indent_ranges.insert(ix, range),
1659                    Ok(ix) => {
1660                        let prev_range = &mut indent_ranges[ix];
1661                        prev_range.end = prev_range.end.max(range.end);
1662                    }
1663                }
1664            }
1665        }
1666
1667        // Find the suggested indentation increases and decreased based on regexes.
1668        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
1669        self.for_each_line(
1670            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
1671                ..Point::new(row_range.end, 0),
1672            |row, line| {
1673                if config
1674                    .decrease_indent_pattern
1675                    .as_ref()
1676                    .map_or(false, |regex| regex.is_match(line))
1677                {
1678                    indent_change_rows.push((row, Ordering::Less));
1679                }
1680                if config
1681                    .increase_indent_pattern
1682                    .as_ref()
1683                    .map_or(false, |regex| regex.is_match(line))
1684                {
1685                    indent_change_rows.push((row + 1, Ordering::Greater));
1686                }
1687            },
1688        );
1689
1690        let mut indent_changes = indent_change_rows.into_iter().peekable();
1691        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
1692            prev_non_blank_row.unwrap_or(0)
1693        } else {
1694            row_range.start.saturating_sub(1)
1695        };
1696        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
1697        Some(row_range.map(move |row| {
1698            let row_start = Point::new(row, self.indent_size_for_line(row).len);
1699
1700            let mut indent_from_prev_row = false;
1701            let mut outdent_from_prev_row = false;
1702            let mut outdent_to_row = u32::MAX;
1703
1704            while let Some((indent_row, delta)) = indent_changes.peek() {
1705                match indent_row.cmp(&row) {
1706                    Ordering::Equal => match delta {
1707                        Ordering::Less => outdent_from_prev_row = true,
1708                        Ordering::Greater => indent_from_prev_row = true,
1709                        _ => {}
1710                    },
1711
1712                    Ordering::Greater => break,
1713                    Ordering::Less => {}
1714                }
1715
1716                indent_changes.next();
1717            }
1718
1719            for range in &indent_ranges {
1720                if range.start.row >= row {
1721                    break;
1722                }
1723                if range.start.row == prev_row && range.end > row_start {
1724                    indent_from_prev_row = true;
1725                }
1726                if range.end > prev_row_start && range.end <= row_start {
1727                    outdent_to_row = outdent_to_row.min(range.start.row);
1728                }
1729            }
1730
1731            let suggestion = if outdent_to_row == prev_row
1732                || (outdent_from_prev_row && indent_from_prev_row)
1733            {
1734                Some(IndentSuggestion {
1735                    basis_row: prev_row,
1736                    delta: Ordering::Equal,
1737                })
1738            } else if indent_from_prev_row {
1739                Some(IndentSuggestion {
1740                    basis_row: prev_row,
1741                    delta: Ordering::Greater,
1742                })
1743            } else if outdent_to_row < prev_row {
1744                Some(IndentSuggestion {
1745                    basis_row: outdent_to_row,
1746                    delta: Ordering::Equal,
1747                })
1748            } else if outdent_from_prev_row {
1749                Some(IndentSuggestion {
1750                    basis_row: prev_row,
1751                    delta: Ordering::Less,
1752                })
1753            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
1754            {
1755                Some(IndentSuggestion {
1756                    basis_row: prev_row,
1757                    delta: Ordering::Equal,
1758                })
1759            } else {
1760                None
1761            };
1762
1763            prev_row = row;
1764            prev_row_start = row_start;
1765            suggestion
1766        }))
1767    }
1768
1769    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
1770        while row > 0 {
1771            row -= 1;
1772            if !self.is_line_blank(row) {
1773                return Some(row);
1774            }
1775        }
1776        None
1777    }
1778
1779    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
1780        let range = range.start.to_offset(self)..range.end.to_offset(self);
1781
1782        let mut syntax = None;
1783        let mut diagnostic_endpoints = Vec::new();
1784        if language_aware {
1785            let captures = self.syntax.captures(range.clone(), &self.text, |grammar| {
1786                grammar.highlights_query.as_ref()
1787            });
1788            let highlight_maps = captures
1789                .grammars()
1790                .into_iter()
1791                .map(|grammar| grammar.highlight_map())
1792                .collect();
1793            syntax = Some((captures, highlight_maps));
1794            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
1795                diagnostic_endpoints.push(DiagnosticEndpoint {
1796                    offset: entry.range.start,
1797                    is_start: true,
1798                    severity: entry.diagnostic.severity,
1799                    is_unnecessary: entry.diagnostic.is_unnecessary,
1800                });
1801                diagnostic_endpoints.push(DiagnosticEndpoint {
1802                    offset: entry.range.end,
1803                    is_start: false,
1804                    severity: entry.diagnostic.severity,
1805                    is_unnecessary: entry.diagnostic.is_unnecessary,
1806                });
1807            }
1808            diagnostic_endpoints
1809                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
1810        }
1811
1812        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostic_endpoints)
1813    }
1814
1815    pub fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
1816        let mut line = String::new();
1817        let mut row = range.start.row;
1818        for chunk in self
1819            .as_rope()
1820            .chunks_in_range(range.to_offset(self))
1821            .chain(["\n"])
1822        {
1823            for (newline_ix, text) in chunk.split('\n').enumerate() {
1824                if newline_ix > 0 {
1825                    callback(row, &line);
1826                    row += 1;
1827                    line.clear();
1828                }
1829                line.push_str(text);
1830            }
1831        }
1832    }
1833
1834    pub fn language(&self) -> Option<&Arc<Language>> {
1835        self.language.as_ref()
1836    }
1837
1838    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
1839        let offset = position.to_offset(self);
1840        self.syntax
1841            .layers_for_range(offset..offset, &self.text)
1842            .last()
1843            .map(|info| info.language)
1844    }
1845
1846    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
1847        let mut start = start.to_offset(self);
1848        let mut end = start;
1849        let mut next_chars = self.chars_at(start).peekable();
1850        let mut prev_chars = self.reversed_chars_at(start).peekable();
1851        let word_kind = cmp::max(
1852            prev_chars.peek().copied().map(char_kind),
1853            next_chars.peek().copied().map(char_kind),
1854        );
1855
1856        for ch in prev_chars {
1857            if Some(char_kind(ch)) == word_kind && ch != '\n' {
1858                start -= ch.len_utf8();
1859            } else {
1860                break;
1861            }
1862        }
1863
1864        for ch in next_chars {
1865            if Some(char_kind(ch)) == word_kind && ch != '\n' {
1866                end += ch.len_utf8();
1867            } else {
1868                break;
1869            }
1870        }
1871
1872        (start..end, word_kind)
1873    }
1874
1875    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
1876        let range = range.start.to_offset(self)..range.end.to_offset(self);
1877        let mut result: Option<Range<usize>> = None;
1878        'outer: for layer in self.syntax.layers_for_range(range.clone(), &self.text) {
1879            let mut cursor = layer.node.walk();
1880
1881            // Descend to the first leaf that touches the start of the range,
1882            // and if the range is non-empty, extends beyond the start.
1883            while cursor.goto_first_child_for_byte(range.start).is_some() {
1884                if !range.is_empty() && cursor.node().end_byte() == range.start {
1885                    cursor.goto_next_sibling();
1886                }
1887            }
1888
1889            // Ascend to the smallest ancestor that strictly contains the range.
1890            loop {
1891                let node_range = cursor.node().byte_range();
1892                if node_range.start <= range.start
1893                    && node_range.end >= range.end
1894                    && node_range.len() > range.len()
1895                {
1896                    break;
1897                }
1898                if !cursor.goto_parent() {
1899                    continue 'outer;
1900                }
1901            }
1902
1903            let left_node = cursor.node();
1904            let mut layer_result = left_node.byte_range();
1905
1906            // For an empty range, try to find another node immediately to the right of the range.
1907            if left_node.end_byte() == range.start {
1908                let mut right_node = None;
1909                while !cursor.goto_next_sibling() {
1910                    if !cursor.goto_parent() {
1911                        break;
1912                    }
1913                }
1914
1915                while cursor.node().start_byte() == range.start {
1916                    right_node = Some(cursor.node());
1917                    if !cursor.goto_first_child() {
1918                        break;
1919                    }
1920                }
1921
1922                // If there is a candidate node on both sides of the (empty) range, then
1923                // decide between the two by favoring a named node over an anonymous token.
1924                // If both nodes are the same in that regard, favor the right one.
1925                if let Some(right_node) = right_node {
1926                    if right_node.is_named() || !left_node.is_named() {
1927                        layer_result = right_node.byte_range();
1928                    }
1929                }
1930            }
1931
1932            if let Some(previous_result) = &result {
1933                if previous_result.len() < layer_result.len() {
1934                    continue;
1935                }
1936            }
1937            result = Some(layer_result);
1938        }
1939
1940        result
1941    }
1942
1943    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
1944        self.outline_items_containing(0..self.len(), theme)
1945            .map(Outline::new)
1946    }
1947
1948    pub fn symbols_containing<T: ToOffset>(
1949        &self,
1950        position: T,
1951        theme: Option<&SyntaxTheme>,
1952    ) -> Option<Vec<OutlineItem<Anchor>>> {
1953        let position = position.to_offset(self);
1954        let mut items = self.outline_items_containing(
1955            position.saturating_sub(1)..self.len().min(position + 1),
1956            theme,
1957        )?;
1958        let mut prev_depth = None;
1959        items.retain(|item| {
1960            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
1961            prev_depth = Some(item.depth);
1962            result
1963        });
1964        Some(items)
1965    }
1966
1967    fn outline_items_containing(
1968        &self,
1969        range: Range<usize>,
1970        theme: Option<&SyntaxTheme>,
1971    ) -> Option<Vec<OutlineItem<Anchor>>> {
1972        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1973            grammar.outline_config.as_ref().map(|c| &c.query)
1974        });
1975        let configs = matches
1976            .grammars()
1977            .iter()
1978            .map(|g| g.outline_config.as_ref().unwrap())
1979            .collect::<Vec<_>>();
1980
1981        let mut chunks = self.chunks(0..self.len(), true);
1982        let mut stack = Vec::<Range<usize>>::new();
1983        let mut items = Vec::new();
1984        while let Some(mat) = matches.peek() {
1985            let config = &configs[mat.grammar_index];
1986            let item_node = mat.captures.iter().find_map(|cap| {
1987                if cap.index == config.item_capture_ix {
1988                    Some(cap.node)
1989                } else {
1990                    None
1991                }
1992            })?;
1993
1994            let item_range = item_node.byte_range();
1995            if item_range.end < range.start || item_range.start > range.end {
1996                matches.advance();
1997                continue;
1998            }
1999
2000            // TODO - move later, after processing captures
2001
2002            let mut text = String::new();
2003            let mut name_ranges = Vec::new();
2004            let mut highlight_ranges = Vec::new();
2005            for capture in mat.captures {
2006                let node_is_name;
2007                if capture.index == config.name_capture_ix {
2008                    node_is_name = true;
2009                } else if Some(capture.index) == config.context_capture_ix {
2010                    node_is_name = false;
2011                } else {
2012                    continue;
2013                }
2014
2015                let range = capture.node.start_byte()..capture.node.end_byte();
2016                if !text.is_empty() {
2017                    text.push(' ');
2018                }
2019                if node_is_name {
2020                    let mut start = text.len();
2021                    let end = start + range.len();
2022
2023                    // When multiple names are captured, then the matcheable text
2024                    // includes the whitespace in between the names.
2025                    if !name_ranges.is_empty() {
2026                        start -= 1;
2027                    }
2028
2029                    name_ranges.push(start..end);
2030                }
2031
2032                let mut offset = range.start;
2033                chunks.seek(offset);
2034                for mut chunk in chunks.by_ref() {
2035                    if chunk.text.len() > range.end - offset {
2036                        chunk.text = &chunk.text[0..(range.end - offset)];
2037                        offset = range.end;
2038                    } else {
2039                        offset += chunk.text.len();
2040                    }
2041                    let style = chunk
2042                        .syntax_highlight_id
2043                        .zip(theme)
2044                        .and_then(|(highlight, theme)| highlight.style(theme));
2045                    if let Some(style) = style {
2046                        let start = text.len();
2047                        let end = start + chunk.text.len();
2048                        highlight_ranges.push((start..end, style));
2049                    }
2050                    text.push_str(chunk.text);
2051                    if offset >= range.end {
2052                        break;
2053                    }
2054                }
2055            }
2056
2057            matches.advance();
2058            while stack.last().map_or(false, |prev_range| {
2059                prev_range.start > item_range.start || prev_range.end < item_range.end
2060            }) {
2061                stack.pop();
2062            }
2063            stack.push(item_range.clone());
2064
2065            items.push(OutlineItem {
2066                depth: stack.len() - 1,
2067                range: self.anchor_after(item_range.start)..self.anchor_before(item_range.end),
2068                text,
2069                highlight_ranges,
2070                name_ranges,
2071            })
2072        }
2073        Some(items)
2074    }
2075
2076    pub fn enclosing_bracket_ranges<T: ToOffset>(
2077        &self,
2078        range: Range<T>,
2079    ) -> Option<(Range<usize>, Range<usize>)> {
2080        // Find bracket pairs that *inclusively* contain the given range.
2081        let range = range.start.to_offset(self).saturating_sub(1)
2082            ..self.len().min(range.end.to_offset(self) + 1);
2083        let mut matches = self.syntax.matches(range, &self.text, |grammar| {
2084            grammar.brackets_config.as_ref().map(|c| &c.query)
2085        });
2086        let configs = matches
2087            .grammars()
2088            .iter()
2089            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
2090            .collect::<Vec<_>>();
2091
2092        // Get the ranges of the innermost pair of brackets.
2093        let mut result: Option<(Range<usize>, Range<usize>)> = None;
2094        while let Some(mat) = matches.peek() {
2095            let mut open = None;
2096            let mut close = None;
2097            let config = &configs[mat.grammar_index];
2098            for capture in mat.captures {
2099                if capture.index == config.open_capture_ix {
2100                    open = Some(capture.node.byte_range());
2101                } else if capture.index == config.close_capture_ix {
2102                    close = Some(capture.node.byte_range());
2103                }
2104            }
2105
2106            matches.advance();
2107
2108            if let Some((open, close)) = open.zip(close) {
2109                let len = close.end - open.start;
2110
2111                if let Some((existing_open, existing_close)) = &result {
2112                    let existing_len = existing_close.end - existing_open.start;
2113                    if len > existing_len {
2114                        continue;
2115                    }
2116                }
2117
2118                result = Some((open, close));
2119            }
2120        }
2121
2122        result
2123    }
2124
2125    #[allow(clippy::type_complexity)]
2126    pub fn remote_selections_in_range(
2127        &self,
2128        range: Range<Anchor>,
2129    ) -> impl Iterator<
2130        Item = (
2131            ReplicaId,
2132            bool,
2133            impl Iterator<Item = &Selection<Anchor>> + '_,
2134        ),
2135    > + '_ {
2136        self.remote_selections
2137            .iter()
2138            .filter(|(replica_id, set)| {
2139                **replica_id != self.text.replica_id() && !set.selections.is_empty()
2140            })
2141            .map(move |(replica_id, set)| {
2142                let start_ix = match set.selections.binary_search_by(|probe| {
2143                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
2144                }) {
2145                    Ok(ix) | Err(ix) => ix,
2146                };
2147                let end_ix = match set.selections.binary_search_by(|probe| {
2148                    probe.start.cmp(&range.end, self).then(Ordering::Less)
2149                }) {
2150                    Ok(ix) | Err(ix) => ix,
2151                };
2152
2153                (
2154                    *replica_id,
2155                    set.line_mode,
2156                    set.selections[start_ix..end_ix].iter(),
2157                )
2158            })
2159    }
2160
2161    pub fn diagnostics_in_range<'a, T, O>(
2162        &'a self,
2163        search_range: Range<T>,
2164        reversed: bool,
2165    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2166    where
2167        T: 'a + Clone + ToOffset,
2168        O: 'a + FromAnchor,
2169    {
2170        self.diagnostics.range(search_range, self, true, reversed)
2171    }
2172
2173    pub fn diagnostic_groups(&self) -> Vec<DiagnosticGroup<Anchor>> {
2174        let mut groups = Vec::new();
2175        self.diagnostics.groups(&mut groups, self);
2176        groups
2177    }
2178
2179    pub fn diagnostic_group<'a, O>(
2180        &'a self,
2181        group_id: usize,
2182    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2183    where
2184        O: 'a + FromAnchor,
2185    {
2186        self.diagnostics.group(group_id, self)
2187    }
2188
2189    pub fn diagnostics_update_count(&self) -> usize {
2190        self.diagnostics_update_count
2191    }
2192
2193    pub fn parse_count(&self) -> usize {
2194        self.parse_count
2195    }
2196
2197    pub fn selections_update_count(&self) -> usize {
2198        self.selections_update_count
2199    }
2200
2201    pub fn file(&self) -> Option<&dyn File> {
2202        self.file.as_deref()
2203    }
2204
2205    pub fn file_update_count(&self) -> usize {
2206        self.file_update_count
2207    }
2208}
2209
2210pub fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
2211    indent_size_for_text(text.chars_at(Point::new(row, 0)))
2212}
2213
2214pub fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
2215    let mut result = IndentSize::spaces(0);
2216    for c in text {
2217        let kind = match c {
2218            ' ' => IndentKind::Space,
2219            '\t' => IndentKind::Tab,
2220            _ => break,
2221        };
2222        if result.len == 0 {
2223            result.kind = kind;
2224        }
2225        result.len += 1;
2226    }
2227    result
2228}
2229
2230impl Clone for BufferSnapshot {
2231    fn clone(&self) -> Self {
2232        Self {
2233            text: self.text.clone(),
2234            syntax: self.syntax.clone(),
2235            file: self.file.clone(),
2236            remote_selections: self.remote_selections.clone(),
2237            diagnostics: self.diagnostics.clone(),
2238            selections_update_count: self.selections_update_count,
2239            diagnostics_update_count: self.diagnostics_update_count,
2240            file_update_count: self.file_update_count,
2241            language: self.language.clone(),
2242            parse_count: self.parse_count,
2243        }
2244    }
2245}
2246
2247impl Deref for BufferSnapshot {
2248    type Target = text::BufferSnapshot;
2249
2250    fn deref(&self) -> &Self::Target {
2251        &self.text
2252    }
2253}
2254
2255unsafe impl<'a> Send for BufferChunks<'a> {}
2256
2257impl<'a> BufferChunks<'a> {
2258    pub(crate) fn new(
2259        text: &'a Rope,
2260        range: Range<usize>,
2261        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
2262        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
2263    ) -> Self {
2264        let mut highlights = None;
2265        if let Some((captures, highlight_maps)) = syntax {
2266            highlights = Some(BufferChunkHighlights {
2267                captures,
2268                next_capture: None,
2269                stack: Default::default(),
2270                highlight_maps,
2271            })
2272        }
2273
2274        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2275        let chunks = text.chunks_in_range(range.clone());
2276
2277        BufferChunks {
2278            range,
2279            chunks,
2280            diagnostic_endpoints,
2281            error_depth: 0,
2282            warning_depth: 0,
2283            information_depth: 0,
2284            hint_depth: 0,
2285            unnecessary_depth: 0,
2286            highlights,
2287        }
2288    }
2289
2290    pub fn seek(&mut self, offset: usize) {
2291        self.range.start = offset;
2292        self.chunks.seek(self.range.start);
2293        if let Some(highlights) = self.highlights.as_mut() {
2294            highlights
2295                .stack
2296                .retain(|(end_offset, _)| *end_offset > offset);
2297            if let Some(capture) = &highlights.next_capture {
2298                if offset >= capture.node.start_byte() {
2299                    let next_capture_end = capture.node.end_byte();
2300                    if offset < next_capture_end {
2301                        highlights.stack.push((
2302                            next_capture_end,
2303                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
2304                        ));
2305                    }
2306                    highlights.next_capture.take();
2307                }
2308            }
2309            highlights.captures.set_byte_range(self.range.clone());
2310        }
2311    }
2312
2313    pub fn offset(&self) -> usize {
2314        self.range.start
2315    }
2316
2317    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2318        let depth = match endpoint.severity {
2319            DiagnosticSeverity::ERROR => &mut self.error_depth,
2320            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2321            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2322            DiagnosticSeverity::HINT => &mut self.hint_depth,
2323            _ => return,
2324        };
2325        if endpoint.is_start {
2326            *depth += 1;
2327        } else {
2328            *depth -= 1;
2329        }
2330
2331        if endpoint.is_unnecessary {
2332            if endpoint.is_start {
2333                self.unnecessary_depth += 1;
2334            } else {
2335                self.unnecessary_depth -= 1;
2336            }
2337        }
2338    }
2339
2340    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2341        if self.error_depth > 0 {
2342            Some(DiagnosticSeverity::ERROR)
2343        } else if self.warning_depth > 0 {
2344            Some(DiagnosticSeverity::WARNING)
2345        } else if self.information_depth > 0 {
2346            Some(DiagnosticSeverity::INFORMATION)
2347        } else if self.hint_depth > 0 {
2348            Some(DiagnosticSeverity::HINT)
2349        } else {
2350            None
2351        }
2352    }
2353
2354    fn current_code_is_unnecessary(&self) -> bool {
2355        self.unnecessary_depth > 0
2356    }
2357}
2358
2359impl<'a> Iterator for BufferChunks<'a> {
2360    type Item = Chunk<'a>;
2361
2362    fn next(&mut self) -> Option<Self::Item> {
2363        let mut next_capture_start = usize::MAX;
2364        let mut next_diagnostic_endpoint = usize::MAX;
2365
2366        if let Some(highlights) = self.highlights.as_mut() {
2367            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2368                if *parent_capture_end <= self.range.start {
2369                    highlights.stack.pop();
2370                } else {
2371                    break;
2372                }
2373            }
2374
2375            if highlights.next_capture.is_none() {
2376                highlights.next_capture = highlights.captures.next();
2377            }
2378
2379            while let Some(capture) = highlights.next_capture.as_ref() {
2380                if self.range.start < capture.node.start_byte() {
2381                    next_capture_start = capture.node.start_byte();
2382                    break;
2383                } else {
2384                    let highlight_id =
2385                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
2386                    highlights
2387                        .stack
2388                        .push((capture.node.end_byte(), highlight_id));
2389                    highlights.next_capture = highlights.captures.next();
2390                }
2391            }
2392        }
2393
2394        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2395            if endpoint.offset <= self.range.start {
2396                self.update_diagnostic_depths(endpoint);
2397                self.diagnostic_endpoints.next();
2398            } else {
2399                next_diagnostic_endpoint = endpoint.offset;
2400                break;
2401            }
2402        }
2403
2404        if let Some(chunk) = self.chunks.peek() {
2405            let chunk_start = self.range.start;
2406            let mut chunk_end = (self.chunks.offset() + chunk.len())
2407                .min(next_capture_start)
2408                .min(next_diagnostic_endpoint);
2409            let mut highlight_id = None;
2410            if let Some(highlights) = self.highlights.as_ref() {
2411                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2412                    chunk_end = chunk_end.min(*parent_capture_end);
2413                    highlight_id = Some(*parent_highlight_id);
2414                }
2415            }
2416
2417            let slice =
2418                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2419            self.range.start = chunk_end;
2420            if self.range.start == self.chunks.offset() + chunk.len() {
2421                self.chunks.next().unwrap();
2422            }
2423
2424            Some(Chunk {
2425                text: slice,
2426                syntax_highlight_id: highlight_id,
2427                highlight_style: None,
2428                diagnostic_severity: self.current_diagnostic_severity(),
2429                is_unnecessary: self.current_code_is_unnecessary(),
2430            })
2431        } else {
2432            None
2433        }
2434    }
2435}
2436
2437impl operation_queue::Operation for Operation {
2438    fn lamport_timestamp(&self) -> clock::Lamport {
2439        match self {
2440            Operation::Buffer(_) => {
2441                unreachable!("buffer operations should never be deferred at this layer")
2442            }
2443            Operation::UpdateDiagnostics {
2444                lamport_timestamp, ..
2445            }
2446            | Operation::UpdateSelections {
2447                lamport_timestamp, ..
2448            }
2449            | Operation::UpdateCompletionTriggers {
2450                lamport_timestamp, ..
2451            } => *lamport_timestamp,
2452        }
2453    }
2454}
2455
2456impl Default for Diagnostic {
2457    fn default() -> Self {
2458        Self {
2459            code: None,
2460            severity: DiagnosticSeverity::ERROR,
2461            message: Default::default(),
2462            group_id: 0,
2463            is_primary: false,
2464            is_valid: true,
2465            is_disk_based: false,
2466            is_unnecessary: false,
2467        }
2468    }
2469}
2470
2471impl IndentSize {
2472    pub fn spaces(len: u32) -> Self {
2473        Self {
2474            len,
2475            kind: IndentKind::Space,
2476        }
2477    }
2478
2479    pub fn tab() -> Self {
2480        Self {
2481            len: 1,
2482            kind: IndentKind::Tab,
2483        }
2484    }
2485
2486    pub fn chars(&self) -> impl Iterator<Item = char> {
2487        iter::repeat(self.char()).take(self.len as usize)
2488    }
2489
2490    pub fn char(&self) -> char {
2491        match self.kind {
2492            IndentKind::Space => ' ',
2493            IndentKind::Tab => '\t',
2494        }
2495    }
2496
2497    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
2498        match direction {
2499            Ordering::Less => {
2500                if self.kind == size.kind && self.len >= size.len {
2501                    self.len -= size.len;
2502                }
2503            }
2504            Ordering::Equal => {}
2505            Ordering::Greater => {
2506                if self.len == 0 {
2507                    self = size;
2508                } else if self.kind == size.kind {
2509                    self.len += size.len;
2510                }
2511            }
2512        }
2513        self
2514    }
2515}
2516
2517impl Completion {
2518    pub fn sort_key(&self) -> (usize, &str) {
2519        let kind_key = match self.lsp_completion.kind {
2520            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2521            _ => 1,
2522        };
2523        (kind_key, &self.label.text[self.label.filter_range.clone()])
2524    }
2525
2526    pub fn is_snippet(&self) -> bool {
2527        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2528    }
2529}
2530
2531pub fn contiguous_ranges(
2532    values: impl Iterator<Item = u32>,
2533    max_len: usize,
2534) -> impl Iterator<Item = Range<u32>> {
2535    let mut values = values;
2536    let mut current_range: Option<Range<u32>> = None;
2537    std::iter::from_fn(move || loop {
2538        if let Some(value) = values.next() {
2539            if let Some(range) = &mut current_range {
2540                if value == range.end && range.len() < max_len {
2541                    range.end += 1;
2542                    continue;
2543                }
2544            }
2545
2546            let prev_range = current_range.clone();
2547            current_range = Some(value..(value + 1));
2548            if prev_range.is_some() {
2549                return prev_range;
2550            }
2551        } else {
2552            return current_range.take();
2553        }
2554    })
2555}
2556
2557pub fn char_kind(c: char) -> CharKind {
2558    if c.is_whitespace() {
2559        CharKind::Whitespace
2560    } else if c.is_alphanumeric() || c == '_' {
2561        CharKind::Word
2562    } else {
2563        CharKind::Punctuation
2564    }
2565}