buffer.rs

   1use crate::diagnostic_set::DiagnosticEntry;
   2pub use crate::{
   3    diagnostic_set::DiagnosticSet,
   4    highlight_map::{HighlightId, HighlightMap},
   5    proto, BracketPair, Grammar, Language, LanguageConfig, LanguageRegistry, LanguageServerConfig,
   6    PLAIN_TEXT,
   7};
   8use anyhow::{anyhow, Result};
   9use clock::ReplicaId;
  10use futures::FutureExt as _;
  11use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, MutableAppContext, Task};
  12use lazy_static::lazy_static;
  13use lsp::LanguageServer;
  14use parking_lot::Mutex;
  15use postage::{prelude::Stream, sink::Sink, watch};
  16use similar::{ChangeTag, TextDiff};
  17use smol::future::yield_now;
  18use std::{
  19    any::Any,
  20    cell::RefCell,
  21    cmp,
  22    collections::{BTreeMap, HashMap, HashSet},
  23    ffi::OsString,
  24    future::Future,
  25    iter::{Iterator, Peekable},
  26    ops::{Deref, DerefMut, Range},
  27    path::{Path, PathBuf},
  28    str,
  29    sync::Arc,
  30    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  31    vec,
  32};
  33use text::operation_queue::OperationQueue;
  34pub use text::{Buffer as TextBuffer, Operation as _, *};
  35use theme::SyntaxTheme;
  36use tree_sitter::{InputEdit, Parser, QueryCursor, Tree};
  37use util::{post_inc, TryFutureExt as _};
  38
  39#[cfg(any(test, feature = "test-support"))]
  40pub use tree_sitter_rust;
  41
  42pub use lsp::DiagnosticSeverity;
  43
  44thread_local! {
  45    static PARSER: RefCell<Parser> = RefCell::new(Parser::new());
  46}
  47
  48lazy_static! {
  49    static ref QUERY_CURSORS: Mutex<Vec<QueryCursor>> = Default::default();
  50}
  51
  52// TODO - Make this configurable
  53const INDENT_SIZE: u32 = 4;
  54
  55pub struct Buffer {
  56    text: TextBuffer,
  57    file: Option<Box<dyn File>>,
  58    saved_version: clock::Global,
  59    saved_mtime: SystemTime,
  60    language: Option<Arc<Language>>,
  61    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  62    pending_autoindent: Option<Task<()>>,
  63    sync_parse_timeout: Duration,
  64    syntax_tree: Mutex<Option<SyntaxTree>>,
  65    parsing_in_background: bool,
  66    parse_count: usize,
  67    diagnostics: DiagnosticSet,
  68    diagnostics_update_count: usize,
  69    language_server: Option<LanguageServerState>,
  70    deferred_ops: OperationQueue<Operation>,
  71    #[cfg(test)]
  72    pub(crate) operations: Vec<Operation>,
  73}
  74
  75pub struct BufferSnapshot {
  76    text: text::BufferSnapshot,
  77    tree: Option<Tree>,
  78    diagnostics: DiagnosticSet,
  79    diagnostics_update_count: usize,
  80    is_parsing: bool,
  81    language: Option<Arc<Language>>,
  82    parse_count: usize,
  83}
  84
  85#[derive(Clone, Debug, PartialEq, Eq)]
  86pub struct Diagnostic {
  87    pub severity: DiagnosticSeverity,
  88    pub message: String,
  89    pub group_id: usize,
  90    pub is_primary: bool,
  91}
  92
  93struct LanguageServerState {
  94    server: Arc<LanguageServer>,
  95    latest_snapshot: watch::Sender<Option<LanguageServerSnapshot>>,
  96    pending_snapshots: BTreeMap<usize, LanguageServerSnapshot>,
  97    next_version: usize,
  98    _maintain_server: Task<Option<()>>,
  99}
 100
 101#[derive(Clone)]
 102struct LanguageServerSnapshot {
 103    buffer_snapshot: text::BufferSnapshot,
 104    version: usize,
 105    path: Arc<Path>,
 106}
 107
 108#[derive(Clone, Debug)]
 109pub enum Operation {
 110    Buffer(text::Operation),
 111    UpdateDiagnostics {
 112        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 113        lamport_timestamp: clock::Lamport,
 114    },
 115}
 116
 117#[derive(Clone, Debug, Eq, PartialEq)]
 118pub enum Event {
 119    Edited,
 120    Dirtied,
 121    Saved,
 122    FileHandleChanged,
 123    Reloaded,
 124    Reparsed,
 125    DiagnosticsUpdated,
 126    Closed,
 127}
 128
 129pub trait File {
 130    fn worktree_id(&self) -> usize;
 131
 132    fn entry_id(&self) -> Option<usize>;
 133
 134    fn mtime(&self) -> SystemTime;
 135
 136    /// Returns the path of this file relative to the worktree's root directory.
 137    fn path(&self) -> &Arc<Path>;
 138
 139    /// Returns the absolute path of this file.
 140    fn abs_path(&self) -> Option<PathBuf>;
 141
 142    /// Returns the path of this file relative to the worktree's parent directory (this means it
 143    /// includes the name of the worktree's root folder).
 144    fn full_path(&self) -> PathBuf;
 145
 146    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 147    /// of its worktree, then this method will return the name of the worktree itself.
 148    fn file_name(&self) -> Option<OsString>;
 149
 150    fn is_deleted(&self) -> bool;
 151
 152    fn save(
 153        &self,
 154        buffer_id: u64,
 155        text: Rope,
 156        version: clock::Global,
 157        cx: &mut MutableAppContext,
 158    ) -> Task<Result<(clock::Global, SystemTime)>>;
 159
 160    fn load_local(&self, cx: &AppContext) -> Option<Task<Result<String>>>;
 161
 162    fn buffer_updated(&self, buffer_id: u64, operation: Operation, cx: &mut MutableAppContext);
 163
 164    fn buffer_removed(&self, buffer_id: u64, cx: &mut MutableAppContext);
 165
 166    fn boxed_clone(&self) -> Box<dyn File>;
 167
 168    fn as_any(&self) -> &dyn Any;
 169}
 170
 171struct QueryCursorHandle(Option<QueryCursor>);
 172
 173#[derive(Clone)]
 174struct SyntaxTree {
 175    tree: Tree,
 176    version: clock::Global,
 177}
 178
 179#[derive(Clone)]
 180struct AutoindentRequest {
 181    selection_set_ids: HashSet<SelectionSetId>,
 182    before_edit: BufferSnapshot,
 183    edited: Vec<Anchor>,
 184    inserted: Option<Vec<Range<Anchor>>>,
 185}
 186
 187#[derive(Debug)]
 188struct IndentSuggestion {
 189    basis_row: u32,
 190    indent: bool,
 191}
 192
 193struct TextProvider<'a>(&'a Rope);
 194
 195struct BufferChunkHighlights<'a> {
 196    captures: tree_sitter::QueryCaptures<'a, 'a, TextProvider<'a>>,
 197    next_capture: Option<(tree_sitter::QueryMatch<'a, 'a>, usize)>,
 198    stack: Vec<(usize, HighlightId)>,
 199    highlight_map: HighlightMap,
 200    theme: &'a SyntaxTheme,
 201    _query_cursor: QueryCursorHandle,
 202}
 203
 204pub struct BufferChunks<'a> {
 205    range: Range<usize>,
 206    chunks: rope::Chunks<'a>,
 207    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 208    error_depth: usize,
 209    warning_depth: usize,
 210    information_depth: usize,
 211    hint_depth: usize,
 212    highlights: Option<BufferChunkHighlights<'a>>,
 213}
 214
 215#[derive(Clone, Copy, Debug, Default)]
 216pub struct Chunk<'a> {
 217    pub text: &'a str,
 218    pub highlight_style: Option<HighlightStyle>,
 219    pub diagnostic: Option<DiagnosticSeverity>,
 220}
 221
 222pub(crate) struct Diff {
 223    base_version: clock::Global,
 224    new_text: Arc<str>,
 225    changes: Vec<(ChangeTag, usize)>,
 226}
 227
 228#[derive(Clone, Copy)]
 229struct DiagnosticEndpoint {
 230    offset: usize,
 231    is_start: bool,
 232    severity: DiagnosticSeverity,
 233}
 234
 235impl Buffer {
 236    pub fn new<T: Into<Arc<str>>>(
 237        replica_id: ReplicaId,
 238        base_text: T,
 239        cx: &mut ModelContext<Self>,
 240    ) -> Self {
 241        Self::build(
 242            TextBuffer::new(
 243                replica_id,
 244                cx.model_id() as u64,
 245                History::new(base_text.into()),
 246            ),
 247            None,
 248        )
 249    }
 250
 251    pub fn from_file<T: Into<Arc<str>>>(
 252        replica_id: ReplicaId,
 253        base_text: T,
 254        file: Box<dyn File>,
 255        cx: &mut ModelContext<Self>,
 256    ) -> Self {
 257        Self::build(
 258            TextBuffer::new(
 259                replica_id,
 260                cx.model_id() as u64,
 261                History::new(base_text.into()),
 262            ),
 263            Some(file),
 264        )
 265    }
 266
 267    pub fn from_proto(
 268        replica_id: ReplicaId,
 269        message: proto::Buffer,
 270        file: Option<Box<dyn File>>,
 271        cx: &mut ModelContext<Self>,
 272    ) -> Result<Self> {
 273        let mut buffer =
 274            text::Buffer::new(replica_id, message.id, History::new(message.content.into()));
 275        let ops = message
 276            .history
 277            .into_iter()
 278            .map(|op| text::Operation::Edit(proto::deserialize_edit_operation(op)));
 279        buffer.apply_ops(ops)?;
 280        for set in message.selections {
 281            let set = proto::deserialize_selection_set(set);
 282            buffer.add_raw_selection_set(set.id, set);
 283        }
 284        let mut this = Self::build(buffer, file);
 285        this.apply_diagnostic_update(
 286            Arc::from(proto::deserialize_diagnostics(message.diagnostics)),
 287            cx,
 288        );
 289
 290        Ok(this)
 291    }
 292
 293    pub fn to_proto(&self) -> proto::Buffer {
 294        proto::Buffer {
 295            id: self.remote_id(),
 296            content: self.text.base_text().to_string(),
 297            history: self
 298                .text
 299                .history()
 300                .map(proto::serialize_edit_operation)
 301                .collect(),
 302            selections: self
 303                .selection_sets()
 304                .map(|(_, set)| proto::serialize_selection_set(set))
 305                .collect(),
 306            diagnostics: proto::serialize_diagnostics(self.diagnostics.iter()),
 307        }
 308    }
 309
 310    pub fn with_language(
 311        mut self,
 312        language: Option<Arc<Language>>,
 313        language_server: Option<Arc<LanguageServer>>,
 314        cx: &mut ModelContext<Self>,
 315    ) -> Self {
 316        self.set_language(language, language_server, cx);
 317        self
 318    }
 319
 320    fn build(buffer: TextBuffer, file: Option<Box<dyn File>>) -> Self {
 321        let saved_mtime;
 322        if let Some(file) = file.as_ref() {
 323            saved_mtime = file.mtime();
 324        } else {
 325            saved_mtime = UNIX_EPOCH;
 326        }
 327
 328        Self {
 329            saved_mtime,
 330            saved_version: buffer.version(),
 331            text: buffer,
 332            file,
 333            syntax_tree: Mutex::new(None),
 334            parsing_in_background: false,
 335            parse_count: 0,
 336            sync_parse_timeout: Duration::from_millis(1),
 337            autoindent_requests: Default::default(),
 338            pending_autoindent: Default::default(),
 339            language: None,
 340            diagnostics: Default::default(),
 341            diagnostics_update_count: 0,
 342            language_server: None,
 343            deferred_ops: OperationQueue::new(),
 344            #[cfg(test)]
 345            operations: Default::default(),
 346        }
 347    }
 348
 349    pub fn snapshot(&self) -> BufferSnapshot {
 350        BufferSnapshot {
 351            text: self.text.snapshot(),
 352            tree: self.syntax_tree(),
 353            diagnostics: self.diagnostics.clone(),
 354            diagnostics_update_count: self.diagnostics_update_count,
 355            is_parsing: self.parsing_in_background,
 356            language: self.language.clone(),
 357            parse_count: self.parse_count,
 358        }
 359    }
 360
 361    pub fn file(&self) -> Option<&dyn File> {
 362        self.file.as_deref()
 363    }
 364
 365    pub fn save(
 366        &mut self,
 367        cx: &mut ModelContext<Self>,
 368    ) -> Result<Task<Result<(clock::Global, SystemTime)>>> {
 369        let file = self
 370            .file
 371            .as_ref()
 372            .ok_or_else(|| anyhow!("buffer has no file"))?;
 373        let text = self.as_rope().clone();
 374        let version = self.version();
 375        let save = file.save(self.remote_id(), text, version, cx.as_mut());
 376        Ok(cx.spawn(|this, mut cx| async move {
 377            let (version, mtime) = save.await?;
 378            this.update(&mut cx, |this, cx| {
 379                this.did_save(version.clone(), mtime, None, cx);
 380            });
 381            Ok((version, mtime))
 382        }))
 383    }
 384
 385    pub fn set_language(
 386        &mut self,
 387        language: Option<Arc<Language>>,
 388        language_server: Option<Arc<lsp::LanguageServer>>,
 389        cx: &mut ModelContext<Self>,
 390    ) {
 391        self.language = language;
 392        self.language_server = if let Some(server) = language_server {
 393            let (latest_snapshot_tx, mut latest_snapshot_rx) = watch::channel();
 394            Some(LanguageServerState {
 395                latest_snapshot: latest_snapshot_tx,
 396                pending_snapshots: Default::default(),
 397                next_version: 0,
 398                server: server.clone(),
 399                _maintain_server: cx.background().spawn(
 400                    async move {
 401                        let mut prev_snapshot: Option<LanguageServerSnapshot> = None;
 402                        while let Some(snapshot) = latest_snapshot_rx.recv().await {
 403                            if let Some(snapshot) = snapshot {
 404                                let uri = lsp::Url::from_file_path(&snapshot.path).unwrap();
 405                                if let Some(prev_snapshot) = prev_snapshot {
 406                                    let changes = lsp::DidChangeTextDocumentParams {
 407                                        text_document: lsp::VersionedTextDocumentIdentifier::new(
 408                                            uri,
 409                                            snapshot.version as i32,
 410                                        ),
 411                                        content_changes: snapshot
 412                                            .buffer_snapshot
 413                                            .edits_since::<(PointUtf16, usize)>(
 414                                                prev_snapshot.buffer_snapshot.version(),
 415                                            )
 416                                            .map(|edit| {
 417                                                let edit_start = edit.new.start.0;
 418                                                let edit_end = edit_start
 419                                                    + (edit.old.end.0 - edit.old.start.0);
 420                                                let new_text = snapshot
 421                                                    .buffer_snapshot
 422                                                    .text_for_range(
 423                                                        edit.new.start.1..edit.new.end.1,
 424                                                    )
 425                                                    .collect();
 426                                                lsp::TextDocumentContentChangeEvent {
 427                                                    range: Some(lsp::Range::new(
 428                                                        lsp::Position::new(
 429                                                            edit_start.row,
 430                                                            edit_start.column,
 431                                                        ),
 432                                                        lsp::Position::new(
 433                                                            edit_end.row,
 434                                                            edit_end.column,
 435                                                        ),
 436                                                    )),
 437                                                    range_length: None,
 438                                                    text: new_text,
 439                                                }
 440                                            })
 441                                            .collect(),
 442                                    };
 443                                    server
 444                                        .notify::<lsp::notification::DidChangeTextDocument>(changes)
 445                                        .await?;
 446                                } else {
 447                                    server
 448                                        .notify::<lsp::notification::DidOpenTextDocument>(
 449                                            lsp::DidOpenTextDocumentParams {
 450                                                text_document: lsp::TextDocumentItem::new(
 451                                                    uri,
 452                                                    Default::default(),
 453                                                    snapshot.version as i32,
 454                                                    snapshot.buffer_snapshot.text().to_string(),
 455                                                ),
 456                                            },
 457                                        )
 458                                        .await?;
 459                                }
 460
 461                                prev_snapshot = Some(snapshot);
 462                            }
 463                        }
 464                        Ok(())
 465                    }
 466                    .log_err(),
 467                ),
 468            })
 469        } else {
 470            None
 471        };
 472
 473        self.reparse(cx);
 474        self.update_language_server();
 475    }
 476
 477    pub fn did_save(
 478        &mut self,
 479        version: clock::Global,
 480        mtime: SystemTime,
 481        new_file: Option<Box<dyn File>>,
 482        cx: &mut ModelContext<Self>,
 483    ) {
 484        self.saved_mtime = mtime;
 485        self.saved_version = version;
 486        if let Some(new_file) = new_file {
 487            self.file = Some(new_file);
 488        }
 489        if let Some(state) = &self.language_server {
 490            cx.background()
 491                .spawn(
 492                    state
 493                        .server
 494                        .notify::<lsp::notification::DidSaveTextDocument>(
 495                            lsp::DidSaveTextDocumentParams {
 496                                text_document: lsp::TextDocumentIdentifier {
 497                                    uri: lsp::Url::from_file_path(
 498                                        self.file.as_ref().unwrap().abs_path().unwrap(),
 499                                    )
 500                                    .unwrap(),
 501                                },
 502                                text: None,
 503                            },
 504                        ),
 505                )
 506                .detach()
 507        }
 508        cx.emit(Event::Saved);
 509    }
 510
 511    pub fn file_updated(
 512        &mut self,
 513        new_file: Box<dyn File>,
 514        cx: &mut ModelContext<Self>,
 515    ) -> Option<Task<()>> {
 516        let old_file = self.file.as_ref()?;
 517        let mut file_changed = false;
 518        let mut task = None;
 519
 520        if new_file.path() != old_file.path() {
 521            file_changed = true;
 522        }
 523
 524        if new_file.is_deleted() {
 525            if !old_file.is_deleted() {
 526                file_changed = true;
 527                if !self.is_dirty() {
 528                    cx.emit(Event::Dirtied);
 529                }
 530            }
 531        } else {
 532            let new_mtime = new_file.mtime();
 533            if new_mtime != old_file.mtime() {
 534                file_changed = true;
 535
 536                if !self.is_dirty() {
 537                    task = Some(cx.spawn(|this, mut cx| {
 538                        async move {
 539                            let new_text = this.read_with(&cx, |this, cx| {
 540                                this.file.as_ref().and_then(|file| file.load_local(cx))
 541                            });
 542                            if let Some(new_text) = new_text {
 543                                let new_text = new_text.await?;
 544                                let diff = this
 545                                    .read_with(&cx, |this, cx| this.diff(new_text.into(), cx))
 546                                    .await;
 547                                this.update(&mut cx, |this, cx| {
 548                                    if this.apply_diff(diff, cx) {
 549                                        this.saved_version = this.version();
 550                                        this.saved_mtime = new_mtime;
 551                                        cx.emit(Event::Reloaded);
 552                                    }
 553                                });
 554                            }
 555                            Ok(())
 556                        }
 557                        .log_err()
 558                        .map(drop)
 559                    }));
 560                }
 561            }
 562        }
 563
 564        if file_changed {
 565            cx.emit(Event::FileHandleChanged);
 566        }
 567        self.file = Some(new_file);
 568        task
 569    }
 570
 571    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 572        cx.emit(Event::Closed);
 573    }
 574
 575    pub fn language(&self) -> Option<&Arc<Language>> {
 576        self.language.as_ref()
 577    }
 578
 579    pub fn parse_count(&self) -> usize {
 580        self.parse_count
 581    }
 582
 583    pub fn diagnostics_update_count(&self) -> usize {
 584        self.diagnostics_update_count
 585    }
 586
 587    pub(crate) fn syntax_tree(&self) -> Option<Tree> {
 588        if let Some(syntax_tree) = self.syntax_tree.lock().as_mut() {
 589            self.interpolate_tree(syntax_tree);
 590            Some(syntax_tree.tree.clone())
 591        } else {
 592            None
 593        }
 594    }
 595
 596    #[cfg(any(test, feature = "test-support"))]
 597    pub fn is_parsing(&self) -> bool {
 598        self.parsing_in_background
 599    }
 600
 601    #[cfg(test)]
 602    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 603        self.sync_parse_timeout = timeout;
 604    }
 605
 606    fn reparse(&mut self, cx: &mut ModelContext<Self>) -> bool {
 607        if self.parsing_in_background {
 608            return false;
 609        }
 610
 611        if let Some(grammar) = self.grammar().cloned() {
 612            let old_tree = self.syntax_tree();
 613            let text = self.as_rope().clone();
 614            let parsed_version = self.version();
 615            let parse_task = cx.background().spawn({
 616                let grammar = grammar.clone();
 617                async move { Self::parse_text(&text, old_tree, &grammar) }
 618            });
 619
 620            match cx
 621                .background()
 622                .block_with_timeout(self.sync_parse_timeout, parse_task)
 623            {
 624                Ok(new_tree) => {
 625                    self.did_finish_parsing(new_tree, parsed_version, cx);
 626                    return true;
 627                }
 628                Err(parse_task) => {
 629                    self.parsing_in_background = true;
 630                    cx.spawn(move |this, mut cx| async move {
 631                        let new_tree = parse_task.await;
 632                        this.update(&mut cx, move |this, cx| {
 633                            let grammar_changed = this
 634                                .grammar()
 635                                .map_or(true, |curr_grammar| !Arc::ptr_eq(&grammar, curr_grammar));
 636                            let parse_again = this.version.gt(&parsed_version) || grammar_changed;
 637                            this.parsing_in_background = false;
 638                            this.did_finish_parsing(new_tree, parsed_version, cx);
 639
 640                            if parse_again && this.reparse(cx) {
 641                                return;
 642                            }
 643                        });
 644                    })
 645                    .detach();
 646                }
 647            }
 648        }
 649        false
 650    }
 651
 652    fn parse_text(text: &Rope, old_tree: Option<Tree>, grammar: &Grammar) -> Tree {
 653        PARSER.with(|parser| {
 654            let mut parser = parser.borrow_mut();
 655            parser
 656                .set_language(grammar.ts_language)
 657                .expect("incompatible grammar");
 658            let mut chunks = text.chunks_in_range(0..text.len());
 659            let tree = parser
 660                .parse_with(
 661                    &mut move |offset, _| {
 662                        chunks.seek(offset);
 663                        chunks.next().unwrap_or("").as_bytes()
 664                    },
 665                    old_tree.as_ref(),
 666                )
 667                .unwrap();
 668            tree
 669        })
 670    }
 671
 672    fn interpolate_tree(&self, tree: &mut SyntaxTree) {
 673        for edit in self.edits_since::<(usize, Point)>(&tree.version) {
 674            let (bytes, lines) = edit.flatten();
 675            tree.tree.edit(&InputEdit {
 676                start_byte: bytes.new.start,
 677                old_end_byte: bytes.new.start + bytes.old.len(),
 678                new_end_byte: bytes.new.end,
 679                start_position: lines.new.start.to_ts_point(),
 680                old_end_position: (lines.new.start + (lines.old.end - lines.old.start))
 681                    .to_ts_point(),
 682                new_end_position: lines.new.end.to_ts_point(),
 683            });
 684        }
 685        tree.version = self.version();
 686    }
 687
 688    fn did_finish_parsing(
 689        &mut self,
 690        tree: Tree,
 691        version: clock::Global,
 692        cx: &mut ModelContext<Self>,
 693    ) {
 694        self.parse_count += 1;
 695        *self.syntax_tree.lock() = Some(SyntaxTree { tree, version });
 696        self.request_autoindent(cx);
 697        cx.emit(Event::Reparsed);
 698        cx.notify();
 699    }
 700
 701    pub fn update_diagnostics(
 702        &mut self,
 703        version: Option<i32>,
 704        mut diagnostics: Vec<lsp::Diagnostic>,
 705        cx: &mut ModelContext<Self>,
 706    ) -> Result<Operation> {
 707        diagnostics.sort_unstable_by_key(|d| (d.range.start, d.range.end));
 708
 709        let version = version.map(|version| version as usize);
 710        let content = if let Some(version) = version {
 711            let language_server = self.language_server.as_mut().unwrap();
 712            let snapshot = language_server
 713                .pending_snapshots
 714                .get(&version)
 715                .ok_or_else(|| anyhow!("missing snapshot"))?;
 716            &snapshot.buffer_snapshot
 717        } else {
 718            self.deref()
 719        };
 720        let abs_path = self.file.as_ref().and_then(|f| f.abs_path());
 721
 722        let empty_set = HashSet::new();
 723        let disk_based_sources = self
 724            .language
 725            .as_ref()
 726            .and_then(|language| language.disk_based_diagnostic_sources())
 727            .unwrap_or(&empty_set);
 728
 729        let mut edits_since_save = content
 730            .edits_since::<PointUtf16>(&self.saved_version)
 731            .peekable();
 732        let mut last_edit_old_end = PointUtf16::zero();
 733        let mut last_edit_new_end = PointUtf16::zero();
 734        let mut group_ids_by_diagnostic_range = HashMap::new();
 735        let mut diagnostics_by_group_id = HashMap::new();
 736        let mut next_group_id = 0;
 737        'outer: for diagnostic in &diagnostics {
 738            let mut start = diagnostic.range.start.to_point_utf16();
 739            let mut end = diagnostic.range.end.to_point_utf16();
 740            let source = diagnostic.source.as_ref();
 741            let code = diagnostic.code.as_ref();
 742            let group_id = diagnostic_ranges(&diagnostic, abs_path.as_deref())
 743                .find_map(|range| group_ids_by_diagnostic_range.get(&(source, code, range)))
 744                .copied()
 745                .unwrap_or_else(|| {
 746                    let group_id = post_inc(&mut next_group_id);
 747                    for range in diagnostic_ranges(&diagnostic, abs_path.as_deref()) {
 748                        group_ids_by_diagnostic_range.insert((source, code, range), group_id);
 749                    }
 750                    group_id
 751                });
 752
 753            if diagnostic
 754                .source
 755                .as_ref()
 756                .map_or(false, |source| disk_based_sources.contains(source))
 757            {
 758                while let Some(edit) = edits_since_save.peek() {
 759                    if edit.old.end <= start {
 760                        last_edit_old_end = edit.old.end;
 761                        last_edit_new_end = edit.new.end;
 762                        edits_since_save.next();
 763                    } else if edit.old.start <= end && edit.old.end >= start {
 764                        continue 'outer;
 765                    } else {
 766                        break;
 767                    }
 768                }
 769
 770                start = last_edit_new_end + (start - last_edit_old_end);
 771                end = last_edit_new_end + (end - last_edit_old_end);
 772            }
 773
 774            let mut range = content.clip_point_utf16(start, Bias::Left)
 775                ..content.clip_point_utf16(end, Bias::Right);
 776            if range.start == range.end {
 777                range.end.column += 1;
 778                range.end = content.clip_point_utf16(range.end, Bias::Right);
 779                if range.start == range.end && range.end.column > 0 {
 780                    range.start.column -= 1;
 781                    range.start = content.clip_point_utf16(range.start, Bias::Left);
 782                }
 783            }
 784
 785            diagnostics_by_group_id
 786                .entry(group_id)
 787                .or_insert(Vec::new())
 788                .push(DiagnosticEntry {
 789                    range,
 790                    diagnostic: Diagnostic {
 791                        severity: diagnostic.severity.unwrap_or(DiagnosticSeverity::ERROR),
 792                        message: diagnostic.message.clone(),
 793                        group_id,
 794                        is_primary: false,
 795                    },
 796                });
 797        }
 798
 799        drop(edits_since_save);
 800        let new_diagnostics = DiagnosticSet::new(
 801            diagnostics_by_group_id
 802                .into_values()
 803                .flat_map(|mut diagnostics| {
 804                    let primary = diagnostics
 805                        .iter_mut()
 806                        .min_by_key(|entry| entry.diagnostic.severity)
 807                        .unwrap();
 808                    primary.diagnostic.is_primary = true;
 809                    diagnostics
 810                }),
 811            content,
 812        );
 813        self.diagnostics = new_diagnostics;
 814
 815        if let Some(version) = version {
 816            let language_server = self.language_server.as_mut().unwrap();
 817            let versions_to_delete = language_server
 818                .pending_snapshots
 819                .range(..version)
 820                .map(|(v, _)| *v)
 821                .collect::<Vec<_>>();
 822            for version in versions_to_delete {
 823                language_server.pending_snapshots.remove(&version);
 824            }
 825        }
 826
 827        self.diagnostics_update_count += 1;
 828        cx.notify();
 829        cx.emit(Event::DiagnosticsUpdated);
 830        Ok(Operation::UpdateDiagnostics {
 831            diagnostics: Arc::from(self.diagnostics.iter().cloned().collect::<Vec<_>>()),
 832            lamport_timestamp: self.lamport_timestamp(),
 833        })
 834    }
 835
 836    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 837        if let Some(indent_columns) = self.compute_autoindents() {
 838            let indent_columns = cx.background().spawn(indent_columns);
 839            match cx
 840                .background()
 841                .block_with_timeout(Duration::from_micros(500), indent_columns)
 842            {
 843                Ok(indent_columns) => self.apply_autoindents(indent_columns, cx),
 844                Err(indent_columns) => {
 845                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 846                        let indent_columns = indent_columns.await;
 847                        this.update(&mut cx, |this, cx| {
 848                            this.apply_autoindents(indent_columns, cx);
 849                        });
 850                    }));
 851                }
 852            }
 853        }
 854    }
 855
 856    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, u32>>> {
 857        let max_rows_between_yields = 100;
 858        let snapshot = self.snapshot();
 859        if snapshot.language.is_none()
 860            || snapshot.tree.is_none()
 861            || self.autoindent_requests.is_empty()
 862        {
 863            return None;
 864        }
 865
 866        let autoindent_requests = self.autoindent_requests.clone();
 867        Some(async move {
 868            let mut indent_columns = BTreeMap::new();
 869            for request in autoindent_requests {
 870                let old_to_new_rows = request
 871                    .edited
 872                    .iter()
 873                    .map(|anchor| anchor.summary::<Point>(&request.before_edit).row)
 874                    .zip(
 875                        request
 876                            .edited
 877                            .iter()
 878                            .map(|anchor| anchor.summary::<Point>(&snapshot).row),
 879                    )
 880                    .collect::<BTreeMap<u32, u32>>();
 881
 882                let mut old_suggestions = HashMap::<u32, u32>::default();
 883                let old_edited_ranges =
 884                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 885                for old_edited_range in old_edited_ranges {
 886                    let suggestions = request
 887                        .before_edit
 888                        .suggest_autoindents(old_edited_range.clone())
 889                        .into_iter()
 890                        .flatten();
 891                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 892                        let indentation_basis = old_to_new_rows
 893                            .get(&suggestion.basis_row)
 894                            .and_then(|from_row| old_suggestions.get(from_row).copied())
 895                            .unwrap_or_else(|| {
 896                                request
 897                                    .before_edit
 898                                    .indent_column_for_line(suggestion.basis_row)
 899                            });
 900                        let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
 901                        old_suggestions.insert(
 902                            *old_to_new_rows.get(&old_row).unwrap(),
 903                            indentation_basis + delta,
 904                        );
 905                    }
 906                    yield_now().await;
 907                }
 908
 909                // At this point, old_suggestions contains the suggested indentation for all edited lines with respect to the state of the
 910                // buffer before the edit, but keyed by the row for these lines after the edits were applied.
 911                let new_edited_row_ranges =
 912                    contiguous_ranges(old_to_new_rows.values().copied(), max_rows_between_yields);
 913                for new_edited_row_range in new_edited_row_ranges {
 914                    let suggestions = snapshot
 915                        .suggest_autoindents(new_edited_row_range.clone())
 916                        .into_iter()
 917                        .flatten();
 918                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
 919                        let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
 920                        let new_indentation = indent_columns
 921                            .get(&suggestion.basis_row)
 922                            .copied()
 923                            .unwrap_or_else(|| {
 924                                snapshot.indent_column_for_line(suggestion.basis_row)
 925                            })
 926                            + delta;
 927                        if old_suggestions
 928                            .get(&new_row)
 929                            .map_or(true, |old_indentation| new_indentation != *old_indentation)
 930                        {
 931                            indent_columns.insert(new_row, new_indentation);
 932                        }
 933                    }
 934                    yield_now().await;
 935                }
 936
 937                if let Some(inserted) = request.inserted.as_ref() {
 938                    let inserted_row_ranges = contiguous_ranges(
 939                        inserted
 940                            .iter()
 941                            .map(|range| range.to_point(&snapshot))
 942                            .flat_map(|range| range.start.row..range.end.row + 1),
 943                        max_rows_between_yields,
 944                    );
 945                    for inserted_row_range in inserted_row_ranges {
 946                        let suggestions = snapshot
 947                            .suggest_autoindents(inserted_row_range.clone())
 948                            .into_iter()
 949                            .flatten();
 950                        for (row, suggestion) in inserted_row_range.zip(suggestions) {
 951                            let delta = if suggestion.indent { INDENT_SIZE } else { 0 };
 952                            let new_indentation = indent_columns
 953                                .get(&suggestion.basis_row)
 954                                .copied()
 955                                .unwrap_or_else(|| {
 956                                    snapshot.indent_column_for_line(suggestion.basis_row)
 957                                })
 958                                + delta;
 959                            indent_columns.insert(row, new_indentation);
 960                        }
 961                        yield_now().await;
 962                    }
 963                }
 964            }
 965            indent_columns
 966        })
 967    }
 968
 969    fn apply_autoindents(
 970        &mut self,
 971        indent_columns: BTreeMap<u32, u32>,
 972        cx: &mut ModelContext<Self>,
 973    ) {
 974        let selection_set_ids = self
 975            .autoindent_requests
 976            .drain(..)
 977            .flat_map(|req| req.selection_set_ids.clone())
 978            .collect::<HashSet<_>>();
 979
 980        self.start_transaction(selection_set_ids.iter().copied())
 981            .unwrap();
 982        for (row, indent_column) in &indent_columns {
 983            self.set_indent_column_for_line(*row, *indent_column, cx);
 984        }
 985
 986        for selection_set_id in &selection_set_ids {
 987            if let Ok(set) = self.selection_set(*selection_set_id) {
 988                let new_selections = set
 989                    .selections::<Point>(&*self)
 990                    .map(|selection| {
 991                        if selection.start.column == 0 {
 992                            let delta = Point::new(
 993                                0,
 994                                indent_columns
 995                                    .get(&selection.start.row)
 996                                    .copied()
 997                                    .unwrap_or(0),
 998                            );
 999                            if delta.column > 0 {
1000                                return Selection {
1001                                    id: selection.id,
1002                                    goal: selection.goal,
1003                                    reversed: selection.reversed,
1004                                    start: selection.start + delta,
1005                                    end: selection.end + delta,
1006                                };
1007                            }
1008                        }
1009                        selection
1010                    })
1011                    .collect::<Vec<_>>();
1012                self.update_selection_set(*selection_set_id, &new_selections, cx)
1013                    .unwrap();
1014            }
1015        }
1016
1017        self.end_transaction(selection_set_ids.iter().copied(), cx)
1018            .unwrap();
1019    }
1020
1021    fn set_indent_column_for_line(&mut self, row: u32, column: u32, cx: &mut ModelContext<Self>) {
1022        let current_column = self.indent_column_for_line(row);
1023        if column > current_column {
1024            let offset = Point::new(row, 0).to_offset(&*self);
1025            self.edit(
1026                [offset..offset],
1027                " ".repeat((column - current_column) as usize),
1028                cx,
1029            );
1030        } else if column < current_column {
1031            self.edit(
1032                [Point::new(row, 0)..Point::new(row, current_column - column)],
1033                "",
1034                cx,
1035            );
1036        }
1037    }
1038
1039    pub(crate) fn diff(&self, new_text: Arc<str>, cx: &AppContext) -> Task<Diff> {
1040        // TODO: it would be nice to not allocate here.
1041        let old_text = self.text();
1042        let base_version = self.version();
1043        cx.background().spawn(async move {
1044            let changes = TextDiff::from_lines(old_text.as_str(), new_text.as_ref())
1045                .iter_all_changes()
1046                .map(|c| (c.tag(), c.value().len()))
1047                .collect::<Vec<_>>();
1048            Diff {
1049                base_version,
1050                new_text,
1051                changes,
1052            }
1053        })
1054    }
1055
1056    pub(crate) fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> bool {
1057        if self.version == diff.base_version {
1058            self.start_transaction(None).unwrap();
1059            let mut offset = 0;
1060            for (tag, len) in diff.changes {
1061                let range = offset..(offset + len);
1062                match tag {
1063                    ChangeTag::Equal => offset += len,
1064                    ChangeTag::Delete => self.edit(Some(range), "", cx),
1065                    ChangeTag::Insert => {
1066                        self.edit(Some(offset..offset), &diff.new_text[range], cx);
1067                        offset += len;
1068                    }
1069                }
1070            }
1071            self.end_transaction(None, cx).unwrap();
1072            true
1073        } else {
1074            false
1075        }
1076    }
1077
1078    pub fn is_dirty(&self) -> bool {
1079        !self.saved_version.ge(&self.version)
1080            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1081    }
1082
1083    pub fn has_conflict(&self) -> bool {
1084        !self.saved_version.ge(&self.version)
1085            && self
1086                .file
1087                .as_ref()
1088                .map_or(false, |file| file.mtime() > self.saved_mtime)
1089    }
1090
1091    pub fn subscribe(&mut self) -> Subscription {
1092        self.text.subscribe()
1093    }
1094
1095    pub fn start_transaction(
1096        &mut self,
1097        selection_set_ids: impl IntoIterator<Item = SelectionSetId>,
1098    ) -> Result<()> {
1099        self.start_transaction_at(selection_set_ids, Instant::now())
1100    }
1101
1102    pub(crate) fn start_transaction_at(
1103        &mut self,
1104        selection_set_ids: impl IntoIterator<Item = SelectionSetId>,
1105        now: Instant,
1106    ) -> Result<()> {
1107        self.text.start_transaction_at(selection_set_ids, now)
1108    }
1109
1110    pub fn end_transaction(
1111        &mut self,
1112        selection_set_ids: impl IntoIterator<Item = SelectionSetId>,
1113        cx: &mut ModelContext<Self>,
1114    ) -> Result<()> {
1115        self.end_transaction_at(selection_set_ids, Instant::now(), cx)
1116    }
1117
1118    pub(crate) fn end_transaction_at(
1119        &mut self,
1120        selection_set_ids: impl IntoIterator<Item = SelectionSetId>,
1121        now: Instant,
1122        cx: &mut ModelContext<Self>,
1123    ) -> Result<()> {
1124        if let Some(start_version) = self.text.end_transaction_at(selection_set_ids, now) {
1125            let was_dirty = start_version != self.saved_version;
1126            self.did_edit(&start_version, was_dirty, cx);
1127        }
1128        Ok(())
1129    }
1130
1131    fn update_language_server(&mut self) {
1132        let language_server = if let Some(language_server) = self.language_server.as_mut() {
1133            language_server
1134        } else {
1135            return;
1136        };
1137        let abs_path = self
1138            .file
1139            .as_ref()
1140            .map_or(Path::new("/").to_path_buf(), |file| {
1141                file.abs_path().unwrap()
1142            });
1143
1144        let version = post_inc(&mut language_server.next_version);
1145        let snapshot = LanguageServerSnapshot {
1146            buffer_snapshot: self.text.snapshot(),
1147            version,
1148            path: Arc::from(abs_path),
1149        };
1150        language_server
1151            .pending_snapshots
1152            .insert(version, snapshot.clone());
1153        let _ = language_server
1154            .latest_snapshot
1155            .blocking_send(Some(snapshot));
1156    }
1157
1158    pub fn edit<I, S, T>(&mut self, ranges_iter: I, new_text: T, cx: &mut ModelContext<Self>)
1159    where
1160        I: IntoIterator<Item = Range<S>>,
1161        S: ToOffset,
1162        T: Into<String>,
1163    {
1164        self.edit_internal(ranges_iter, new_text, false, cx)
1165    }
1166
1167    pub fn edit_with_autoindent<I, S, T>(
1168        &mut self,
1169        ranges_iter: I,
1170        new_text: T,
1171        cx: &mut ModelContext<Self>,
1172    ) where
1173        I: IntoIterator<Item = Range<S>>,
1174        S: ToOffset,
1175        T: Into<String>,
1176    {
1177        self.edit_internal(ranges_iter, new_text, true, cx)
1178    }
1179
1180    pub fn edit_internal<I, S, T>(
1181        &mut self,
1182        ranges_iter: I,
1183        new_text: T,
1184        autoindent: bool,
1185        cx: &mut ModelContext<Self>,
1186    ) where
1187        I: IntoIterator<Item = Range<S>>,
1188        S: ToOffset,
1189        T: Into<String>,
1190    {
1191        let new_text = new_text.into();
1192
1193        // Skip invalid ranges and coalesce contiguous ones.
1194        let mut ranges: Vec<Range<usize>> = Vec::new();
1195        for range in ranges_iter {
1196            let range = range.start.to_offset(self)..range.end.to_offset(self);
1197            if !new_text.is_empty() || !range.is_empty() {
1198                if let Some(prev_range) = ranges.last_mut() {
1199                    if prev_range.end >= range.start {
1200                        prev_range.end = cmp::max(prev_range.end, range.end);
1201                    } else {
1202                        ranges.push(range);
1203                    }
1204                } else {
1205                    ranges.push(range);
1206                }
1207            }
1208        }
1209        if ranges.is_empty() {
1210            return;
1211        }
1212
1213        self.start_transaction(None).unwrap();
1214        self.pending_autoindent.take();
1215        let autoindent_request = if autoindent && self.language.is_some() {
1216            let before_edit = self.snapshot();
1217            let edited = ranges
1218                .iter()
1219                .filter_map(|range| {
1220                    let start = range.start.to_point(self);
1221                    if new_text.starts_with('\n') && start.column == self.line_len(start.row) {
1222                        None
1223                    } else {
1224                        Some(self.anchor_before(range.start))
1225                    }
1226                })
1227                .collect();
1228            Some((before_edit, edited))
1229        } else {
1230            None
1231        };
1232
1233        let first_newline_ix = new_text.find('\n');
1234        let new_text_len = new_text.len();
1235
1236        let edit = self.text.edit(ranges.iter().cloned(), new_text);
1237
1238        if let Some((before_edit, edited)) = autoindent_request {
1239            let mut inserted = None;
1240            if let Some(first_newline_ix) = first_newline_ix {
1241                let mut delta = 0isize;
1242                inserted = Some(
1243                    ranges
1244                        .iter()
1245                        .map(|range| {
1246                            let start =
1247                                (delta + range.start as isize) as usize + first_newline_ix + 1;
1248                            let end = (delta + range.start as isize) as usize + new_text_len;
1249                            delta +=
1250                                (range.end as isize - range.start as isize) + new_text_len as isize;
1251                            self.anchor_before(start)..self.anchor_after(end)
1252                        })
1253                        .collect(),
1254                );
1255            }
1256
1257            let selection_set_ids = self
1258                .text
1259                .peek_undo_stack()
1260                .unwrap()
1261                .starting_selection_set_ids()
1262                .collect();
1263            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1264                selection_set_ids,
1265                before_edit,
1266                edited,
1267                inserted,
1268            }));
1269        }
1270
1271        self.end_transaction(None, cx).unwrap();
1272        self.send_operation(Operation::Buffer(text::Operation::Edit(edit)), cx);
1273    }
1274
1275    fn did_edit(
1276        &mut self,
1277        old_version: &clock::Global,
1278        was_dirty: bool,
1279        cx: &mut ModelContext<Self>,
1280    ) {
1281        if self.edits_since::<usize>(old_version).next().is_none() {
1282            return;
1283        }
1284
1285        self.reparse(cx);
1286        self.update_language_server();
1287
1288        cx.emit(Event::Edited);
1289        if !was_dirty {
1290            cx.emit(Event::Dirtied);
1291        }
1292        cx.notify();
1293    }
1294
1295    fn grammar(&self) -> Option<&Arc<Grammar>> {
1296        self.language.as_ref().and_then(|l| l.grammar.as_ref())
1297    }
1298
1299    pub fn add_selection_set<T: ToOffset>(
1300        &mut self,
1301        selections: &[Selection<T>],
1302        cx: &mut ModelContext<Self>,
1303    ) -> SelectionSetId {
1304        let operation = self.text.add_selection_set(selections);
1305        if let text::Operation::UpdateSelections { set_id, .. } = &operation {
1306            let set_id = *set_id;
1307            cx.notify();
1308            self.send_operation(Operation::Buffer(operation), cx);
1309            set_id
1310        } else {
1311            unreachable!()
1312        }
1313    }
1314
1315    pub fn update_selection_set<T: ToOffset>(
1316        &mut self,
1317        set_id: SelectionSetId,
1318        selections: &[Selection<T>],
1319        cx: &mut ModelContext<Self>,
1320    ) -> Result<()> {
1321        let operation = self.text.update_selection_set(set_id, selections)?;
1322        cx.notify();
1323        self.send_operation(Operation::Buffer(operation), cx);
1324        Ok(())
1325    }
1326
1327    pub fn set_active_selection_set(
1328        &mut self,
1329        set_id: Option<SelectionSetId>,
1330        cx: &mut ModelContext<Self>,
1331    ) -> Result<()> {
1332        let operation = self.text.set_active_selection_set(set_id)?;
1333        self.send_operation(Operation::Buffer(operation), cx);
1334        Ok(())
1335    }
1336
1337    pub fn remove_selection_set(
1338        &mut self,
1339        set_id: SelectionSetId,
1340        cx: &mut ModelContext<Self>,
1341    ) -> Result<()> {
1342        let operation = self.text.remove_selection_set(set_id)?;
1343        cx.notify();
1344        self.send_operation(Operation::Buffer(operation), cx);
1345        Ok(())
1346    }
1347
1348    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1349        &mut self,
1350        ops: I,
1351        cx: &mut ModelContext<Self>,
1352    ) -> Result<()> {
1353        self.pending_autoindent.take();
1354        let was_dirty = self.is_dirty();
1355        let old_version = self.version.clone();
1356        let mut deferred_ops = Vec::new();
1357        let buffer_ops = ops
1358            .into_iter()
1359            .filter_map(|op| match op {
1360                Operation::Buffer(op) => Some(op),
1361                _ => {
1362                    if self.can_apply_op(&op) {
1363                        self.apply_op(op, cx);
1364                    } else {
1365                        deferred_ops.push(op);
1366                    }
1367                    None
1368                }
1369            })
1370            .collect::<Vec<_>>();
1371        self.text.apply_ops(buffer_ops)?;
1372        self.flush_deferred_ops(cx);
1373        self.did_edit(&old_version, was_dirty, cx);
1374        // Notify independently of whether the buffer was edited as the operations could include a
1375        // selection update.
1376        cx.notify();
1377        Ok(())
1378    }
1379
1380    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1381        let mut deferred_ops = Vec::new();
1382        for op in self.deferred_ops.drain().iter().cloned() {
1383            if self.can_apply_op(&op) {
1384                self.apply_op(op, cx);
1385            } else {
1386                deferred_ops.push(op);
1387            }
1388        }
1389        self.deferred_ops.insert(deferred_ops);
1390    }
1391
1392    fn can_apply_op(&self, operation: &Operation) -> bool {
1393        match operation {
1394            Operation::Buffer(_) => {
1395                unreachable!("buffer operations should never be applied at this layer")
1396            }
1397            Operation::UpdateDiagnostics { diagnostics, .. } => {
1398                diagnostics.iter().all(|diagnostic| {
1399                    self.text.can_resolve(&diagnostic.range.start)
1400                        && self.text.can_resolve(&diagnostic.range.end)
1401                })
1402            }
1403        }
1404    }
1405
1406    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1407        match operation {
1408            Operation::Buffer(_) => {
1409                unreachable!("buffer operations should never be applied at this layer")
1410            }
1411            Operation::UpdateDiagnostics { diagnostics, .. } => {
1412                self.apply_diagnostic_update(diagnostics, cx);
1413            }
1414        }
1415    }
1416
1417    fn apply_diagnostic_update(
1418        &mut self,
1419        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
1420        cx: &mut ModelContext<Self>,
1421    ) {
1422        self.diagnostics = DiagnosticSet::from_sorted_entries(diagnostics.iter().cloned(), self);
1423        self.diagnostics_update_count += 1;
1424        cx.notify();
1425    }
1426
1427    #[cfg(not(test))]
1428    pub fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1429        if let Some(file) = &self.file {
1430            file.buffer_updated(self.remote_id(), operation, cx.as_mut());
1431        }
1432    }
1433
1434    #[cfg(test)]
1435    pub fn send_operation(&mut self, operation: Operation, _: &mut ModelContext<Self>) {
1436        self.operations.push(operation);
1437    }
1438
1439    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1440        self.text.remove_peer(replica_id);
1441        cx.notify();
1442    }
1443
1444    pub fn undo(&mut self, cx: &mut ModelContext<Self>) {
1445        let was_dirty = self.is_dirty();
1446        let old_version = self.version.clone();
1447
1448        for operation in self.text.undo() {
1449            self.send_operation(Operation::Buffer(operation), cx);
1450        }
1451
1452        self.did_edit(&old_version, was_dirty, cx);
1453    }
1454
1455    pub fn redo(&mut self, cx: &mut ModelContext<Self>) {
1456        let was_dirty = self.is_dirty();
1457        let old_version = self.version.clone();
1458
1459        for operation in self.text.redo() {
1460            self.send_operation(Operation::Buffer(operation), cx);
1461        }
1462
1463        self.did_edit(&old_version, was_dirty, cx);
1464    }
1465}
1466
1467#[cfg(any(test, feature = "test-support"))]
1468impl Buffer {
1469    pub fn randomly_edit<T>(
1470        &mut self,
1471        rng: &mut T,
1472        old_range_count: usize,
1473        cx: &mut ModelContext<Self>,
1474    ) where
1475        T: rand::Rng,
1476    {
1477        self.start_transaction(None).unwrap();
1478        self.text.randomly_edit(rng, old_range_count);
1479        self.end_transaction(None, cx).unwrap();
1480    }
1481
1482    pub fn randomly_mutate<T>(&mut self, rng: &mut T, cx: &mut ModelContext<Self>)
1483    where
1484        T: rand::Rng,
1485    {
1486        self.start_transaction(None).unwrap();
1487        self.text.randomly_mutate(rng);
1488        self.end_transaction(None, cx).unwrap();
1489    }
1490}
1491
1492impl Entity for Buffer {
1493    type Event = Event;
1494
1495    fn release(&mut self, cx: &mut gpui::MutableAppContext) {
1496        if let Some(file) = self.file.as_ref() {
1497            file.buffer_removed(self.remote_id(), cx);
1498        }
1499    }
1500}
1501
1502impl Deref for Buffer {
1503    type Target = TextBuffer;
1504
1505    fn deref(&self) -> &Self::Target {
1506        &self.text
1507    }
1508}
1509
1510impl BufferSnapshot {
1511    fn suggest_autoindents<'a>(
1512        &'a self,
1513        row_range: Range<u32>,
1514    ) -> Option<impl Iterator<Item = IndentSuggestion> + 'a> {
1515        let mut query_cursor = QueryCursorHandle::new();
1516        if let Some((grammar, tree)) = self.grammar().zip(self.tree.as_ref()) {
1517            let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1518
1519            // Get the "indentation ranges" that intersect this row range.
1520            let indent_capture_ix = grammar.indents_query.capture_index_for_name("indent");
1521            let end_capture_ix = grammar.indents_query.capture_index_for_name("end");
1522            query_cursor.set_point_range(
1523                Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0).to_ts_point()
1524                    ..Point::new(row_range.end, 0).to_ts_point(),
1525            );
1526            let mut indentation_ranges = Vec::<(Range<Point>, &'static str)>::new();
1527            for mat in query_cursor.matches(
1528                &grammar.indents_query,
1529                tree.root_node(),
1530                TextProvider(self.as_rope()),
1531            ) {
1532                let mut node_kind = "";
1533                let mut start: Option<Point> = None;
1534                let mut end: Option<Point> = None;
1535                for capture in mat.captures {
1536                    if Some(capture.index) == indent_capture_ix {
1537                        node_kind = capture.node.kind();
1538                        start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1539                        end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1540                    } else if Some(capture.index) == end_capture_ix {
1541                        end = Some(Point::from_ts_point(capture.node.start_position().into()));
1542                    }
1543                }
1544
1545                if let Some((start, end)) = start.zip(end) {
1546                    if start.row == end.row {
1547                        continue;
1548                    }
1549
1550                    let range = start..end;
1551                    match indentation_ranges.binary_search_by_key(&range.start, |r| r.0.start) {
1552                        Err(ix) => indentation_ranges.insert(ix, (range, node_kind)),
1553                        Ok(ix) => {
1554                            let prev_range = &mut indentation_ranges[ix];
1555                            prev_range.0.end = prev_range.0.end.max(range.end);
1556                        }
1557                    }
1558                }
1559            }
1560
1561            let mut prev_row = prev_non_blank_row.unwrap_or(0);
1562            Some(row_range.map(move |row| {
1563                let row_start = Point::new(row, self.indent_column_for_line(row));
1564
1565                let mut indent_from_prev_row = false;
1566                let mut outdent_to_row = u32::MAX;
1567                for (range, _node_kind) in &indentation_ranges {
1568                    if range.start.row >= row {
1569                        break;
1570                    }
1571
1572                    if range.start.row == prev_row && range.end > row_start {
1573                        indent_from_prev_row = true;
1574                    }
1575                    if range.end.row >= prev_row && range.end <= row_start {
1576                        outdent_to_row = outdent_to_row.min(range.start.row);
1577                    }
1578                }
1579
1580                let suggestion = if outdent_to_row == prev_row {
1581                    IndentSuggestion {
1582                        basis_row: prev_row,
1583                        indent: false,
1584                    }
1585                } else if indent_from_prev_row {
1586                    IndentSuggestion {
1587                        basis_row: prev_row,
1588                        indent: true,
1589                    }
1590                } else if outdent_to_row < prev_row {
1591                    IndentSuggestion {
1592                        basis_row: outdent_to_row,
1593                        indent: false,
1594                    }
1595                } else {
1596                    IndentSuggestion {
1597                        basis_row: prev_row,
1598                        indent: false,
1599                    }
1600                };
1601
1602                prev_row = row;
1603                suggestion
1604            }))
1605        } else {
1606            None
1607        }
1608    }
1609
1610    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
1611        while row > 0 {
1612            row -= 1;
1613            if !self.is_line_blank(row) {
1614                return Some(row);
1615            }
1616        }
1617        None
1618    }
1619
1620    pub fn chunks<'a, T: ToOffset>(
1621        &'a self,
1622        range: Range<T>,
1623        theme: Option<&'a SyntaxTheme>,
1624    ) -> BufferChunks<'a> {
1625        let range = range.start.to_offset(self)..range.end.to_offset(self);
1626
1627        let mut highlights = None;
1628        let mut diagnostic_endpoints = Vec::<DiagnosticEndpoint>::new();
1629        if let Some(theme) = theme {
1630            for entry in self
1631                .diagnostics
1632                .range::<_, usize>(range.clone(), self, true)
1633            {
1634                diagnostic_endpoints.push(DiagnosticEndpoint {
1635                    offset: entry.range.start,
1636                    is_start: true,
1637                    severity: entry.diagnostic.severity,
1638                });
1639                diagnostic_endpoints.push(DiagnosticEndpoint {
1640                    offset: entry.range.end,
1641                    is_start: false,
1642                    severity: entry.diagnostic.severity,
1643                });
1644            }
1645            diagnostic_endpoints
1646                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
1647
1648            if let Some((grammar, tree)) = self.grammar().zip(self.tree.as_ref()) {
1649                let mut query_cursor = QueryCursorHandle::new();
1650
1651                // TODO - add a Tree-sitter API to remove the need for this.
1652                let cursor = unsafe {
1653                    std::mem::transmute::<_, &'static mut QueryCursor>(query_cursor.deref_mut())
1654                };
1655                let captures = cursor.set_byte_range(range.clone()).captures(
1656                    &grammar.highlights_query,
1657                    tree.root_node(),
1658                    TextProvider(self.text.as_rope()),
1659                );
1660                highlights = Some(BufferChunkHighlights {
1661                    captures,
1662                    next_capture: None,
1663                    stack: Default::default(),
1664                    highlight_map: grammar.highlight_map(),
1665                    _query_cursor: query_cursor,
1666                    theme,
1667                })
1668            }
1669        }
1670
1671        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
1672        let chunks = self.text.as_rope().chunks_in_range(range.clone());
1673
1674        BufferChunks {
1675            range,
1676            chunks,
1677            diagnostic_endpoints,
1678            error_depth: 0,
1679            warning_depth: 0,
1680            information_depth: 0,
1681            hint_depth: 0,
1682            highlights,
1683        }
1684    }
1685
1686    pub fn language(&self) -> Option<&Arc<Language>> {
1687        self.language.as_ref()
1688    }
1689
1690    fn grammar(&self) -> Option<&Arc<Grammar>> {
1691        self.language
1692            .as_ref()
1693            .and_then(|language| language.grammar.as_ref())
1694    }
1695
1696    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
1697        if let Some(tree) = self.tree.as_ref() {
1698            let root = tree.root_node();
1699            let range = range.start.to_offset(self)..range.end.to_offset(self);
1700            let mut node = root.descendant_for_byte_range(range.start, range.end);
1701            while node.map_or(false, |n| n.byte_range() == range) {
1702                node = node.unwrap().parent();
1703            }
1704            node.map(|n| n.byte_range())
1705        } else {
1706            None
1707        }
1708    }
1709
1710    pub fn enclosing_bracket_ranges<T: ToOffset>(
1711        &self,
1712        range: Range<T>,
1713    ) -> Option<(Range<usize>, Range<usize>)> {
1714        let (grammar, tree) = self.grammar().zip(self.tree.as_ref())?;
1715        let open_capture_ix = grammar.brackets_query.capture_index_for_name("open")?;
1716        let close_capture_ix = grammar.brackets_query.capture_index_for_name("close")?;
1717
1718        // Find bracket pairs that *inclusively* contain the given range.
1719        let range = range.start.to_offset(self).saturating_sub(1)..range.end.to_offset(self) + 1;
1720        let mut cursor = QueryCursorHandle::new();
1721        let matches = cursor.set_byte_range(range).matches(
1722            &grammar.brackets_query,
1723            tree.root_node(),
1724            TextProvider(self.as_rope()),
1725        );
1726
1727        // Get the ranges of the innermost pair of brackets.
1728        matches
1729            .filter_map(|mat| {
1730                let open = mat.nodes_for_capture_index(open_capture_ix).next()?;
1731                let close = mat.nodes_for_capture_index(close_capture_ix).next()?;
1732                Some((open.byte_range(), close.byte_range()))
1733            })
1734            .min_by_key(|(open_range, close_range)| close_range.end - open_range.start)
1735    }
1736
1737    pub fn diagnostics_in_range<'a, T, O>(
1738        &'a self,
1739        search_range: Range<T>,
1740    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1741    where
1742        T: 'a + ToOffset,
1743        O: 'a + FromAnchor,
1744    {
1745        self.diagnostics.range(search_range, self, true)
1746    }
1747
1748    pub fn diagnostic_group<'a, O>(
1749        &'a self,
1750        group_id: usize,
1751    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
1752    where
1753        O: 'a + FromAnchor,
1754    {
1755        self.diagnostics.group(group_id, self)
1756    }
1757
1758    pub fn diagnostics_update_count(&self) -> usize {
1759        self.diagnostics_update_count
1760    }
1761
1762    pub fn parse_count(&self) -> usize {
1763        self.parse_count
1764    }
1765}
1766
1767impl Clone for BufferSnapshot {
1768    fn clone(&self) -> Self {
1769        Self {
1770            text: self.text.clone(),
1771            tree: self.tree.clone(),
1772            diagnostics: self.diagnostics.clone(),
1773            diagnostics_update_count: self.diagnostics_update_count,
1774            is_parsing: self.is_parsing,
1775            language: self.language.clone(),
1776            parse_count: self.parse_count,
1777        }
1778    }
1779}
1780
1781impl Deref for BufferSnapshot {
1782    type Target = text::BufferSnapshot;
1783
1784    fn deref(&self) -> &Self::Target {
1785        &self.text
1786    }
1787}
1788
1789impl<'a> tree_sitter::TextProvider<'a> for TextProvider<'a> {
1790    type I = ByteChunks<'a>;
1791
1792    fn text(&mut self, node: tree_sitter::Node) -> Self::I {
1793        ByteChunks(self.0.chunks_in_range(node.byte_range()))
1794    }
1795}
1796
1797struct ByteChunks<'a>(rope::Chunks<'a>);
1798
1799impl<'a> Iterator for ByteChunks<'a> {
1800    type Item = &'a [u8];
1801
1802    fn next(&mut self) -> Option<Self::Item> {
1803        self.0.next().map(str::as_bytes)
1804    }
1805}
1806
1807unsafe impl<'a> Send for BufferChunks<'a> {}
1808
1809impl<'a> BufferChunks<'a> {
1810    pub fn seek(&mut self, offset: usize) {
1811        self.range.start = offset;
1812        self.chunks.seek(self.range.start);
1813        if let Some(highlights) = self.highlights.as_mut() {
1814            highlights
1815                .stack
1816                .retain(|(end_offset, _)| *end_offset > offset);
1817            if let Some((mat, capture_ix)) = &highlights.next_capture {
1818                let capture = mat.captures[*capture_ix as usize];
1819                if offset >= capture.node.start_byte() {
1820                    let next_capture_end = capture.node.end_byte();
1821                    if offset < next_capture_end {
1822                        highlights.stack.push((
1823                            next_capture_end,
1824                            highlights.highlight_map.get(capture.index),
1825                        ));
1826                    }
1827                    highlights.next_capture.take();
1828                }
1829            }
1830            highlights.captures.set_byte_range(self.range.clone());
1831        }
1832    }
1833
1834    pub fn offset(&self) -> usize {
1835        self.range.start
1836    }
1837
1838    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
1839        let depth = match endpoint.severity {
1840            DiagnosticSeverity::ERROR => &mut self.error_depth,
1841            DiagnosticSeverity::WARNING => &mut self.warning_depth,
1842            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
1843            DiagnosticSeverity::HINT => &mut self.hint_depth,
1844            _ => return,
1845        };
1846        if endpoint.is_start {
1847            *depth += 1;
1848        } else {
1849            *depth -= 1;
1850        }
1851    }
1852
1853    fn current_diagnostic_severity(&mut self) -> Option<DiagnosticSeverity> {
1854        if self.error_depth > 0 {
1855            Some(DiagnosticSeverity::ERROR)
1856        } else if self.warning_depth > 0 {
1857            Some(DiagnosticSeverity::WARNING)
1858        } else if self.information_depth > 0 {
1859            Some(DiagnosticSeverity::INFORMATION)
1860        } else if self.hint_depth > 0 {
1861            Some(DiagnosticSeverity::HINT)
1862        } else {
1863            None
1864        }
1865    }
1866}
1867
1868impl<'a> Iterator for BufferChunks<'a> {
1869    type Item = Chunk<'a>;
1870
1871    fn next(&mut self) -> Option<Self::Item> {
1872        let mut next_capture_start = usize::MAX;
1873        let mut next_diagnostic_endpoint = usize::MAX;
1874
1875        if let Some(highlights) = self.highlights.as_mut() {
1876            while let Some((parent_capture_end, _)) = highlights.stack.last() {
1877                if *parent_capture_end <= self.range.start {
1878                    highlights.stack.pop();
1879                } else {
1880                    break;
1881                }
1882            }
1883
1884            if highlights.next_capture.is_none() {
1885                highlights.next_capture = highlights.captures.next();
1886            }
1887
1888            while let Some((mat, capture_ix)) = highlights.next_capture.as_ref() {
1889                let capture = mat.captures[*capture_ix as usize];
1890                if self.range.start < capture.node.start_byte() {
1891                    next_capture_start = capture.node.start_byte();
1892                    break;
1893                } else {
1894                    let highlight_id = highlights.highlight_map.get(capture.index);
1895                    highlights
1896                        .stack
1897                        .push((capture.node.end_byte(), highlight_id));
1898                    highlights.next_capture = highlights.captures.next();
1899                }
1900            }
1901        }
1902
1903        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
1904            if endpoint.offset <= self.range.start {
1905                self.update_diagnostic_depths(endpoint);
1906                self.diagnostic_endpoints.next();
1907            } else {
1908                next_diagnostic_endpoint = endpoint.offset;
1909                break;
1910            }
1911        }
1912
1913        if let Some(chunk) = self.chunks.peek() {
1914            let chunk_start = self.range.start;
1915            let mut chunk_end = (self.chunks.offset() + chunk.len())
1916                .min(next_capture_start)
1917                .min(next_diagnostic_endpoint);
1918            let mut highlight_style = None;
1919            if let Some(highlights) = self.highlights.as_ref() {
1920                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
1921                    chunk_end = chunk_end.min(*parent_capture_end);
1922                    highlight_style = parent_highlight_id.style(highlights.theme);
1923                }
1924            }
1925
1926            let slice =
1927                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
1928            self.range.start = chunk_end;
1929            if self.range.start == self.chunks.offset() + chunk.len() {
1930                self.chunks.next().unwrap();
1931            }
1932
1933            Some(Chunk {
1934                text: slice,
1935                highlight_style,
1936                diagnostic: self.current_diagnostic_severity(),
1937            })
1938        } else {
1939            None
1940        }
1941    }
1942}
1943
1944impl QueryCursorHandle {
1945    fn new() -> Self {
1946        QueryCursorHandle(Some(
1947            QUERY_CURSORS
1948                .lock()
1949                .pop()
1950                .unwrap_or_else(|| QueryCursor::new()),
1951        ))
1952    }
1953}
1954
1955impl Deref for QueryCursorHandle {
1956    type Target = QueryCursor;
1957
1958    fn deref(&self) -> &Self::Target {
1959        self.0.as_ref().unwrap()
1960    }
1961}
1962
1963impl DerefMut for QueryCursorHandle {
1964    fn deref_mut(&mut self) -> &mut Self::Target {
1965        self.0.as_mut().unwrap()
1966    }
1967}
1968
1969impl Drop for QueryCursorHandle {
1970    fn drop(&mut self) {
1971        let mut cursor = self.0.take().unwrap();
1972        cursor.set_byte_range(0..usize::MAX);
1973        cursor.set_point_range(Point::zero().to_ts_point()..Point::MAX.to_ts_point());
1974        QUERY_CURSORS.lock().push(cursor)
1975    }
1976}
1977
1978trait ToTreeSitterPoint {
1979    fn to_ts_point(self) -> tree_sitter::Point;
1980    fn from_ts_point(point: tree_sitter::Point) -> Self;
1981}
1982
1983impl ToTreeSitterPoint for Point {
1984    fn to_ts_point(self) -> tree_sitter::Point {
1985        tree_sitter::Point::new(self.row as usize, self.column as usize)
1986    }
1987
1988    fn from_ts_point(point: tree_sitter::Point) -> Self {
1989        Point::new(point.row as u32, point.column as u32)
1990    }
1991}
1992
1993trait ToPointUtf16 {
1994    fn to_point_utf16(self) -> PointUtf16;
1995}
1996
1997impl ToPointUtf16 for lsp::Position {
1998    fn to_point_utf16(self) -> PointUtf16 {
1999        PointUtf16::new(self.line, self.character)
2000    }
2001}
2002
2003impl operation_queue::Operation for Operation {
2004    fn lamport_timestamp(&self) -> clock::Lamport {
2005        match self {
2006            Operation::Buffer(_) => {
2007                unreachable!("buffer operations should never be deferred at this layer")
2008            }
2009            Operation::UpdateDiagnostics {
2010                lamport_timestamp, ..
2011            } => *lamport_timestamp,
2012        }
2013    }
2014}
2015
2016fn diagnostic_ranges<'a>(
2017    diagnostic: &'a lsp::Diagnostic,
2018    abs_path: Option<&'a Path>,
2019) -> impl 'a + Iterator<Item = Range<PointUtf16>> {
2020    diagnostic
2021        .related_information
2022        .iter()
2023        .flatten()
2024        .filter_map(move |info| {
2025            if info.location.uri.to_file_path().ok()? == abs_path? {
2026                let info_start = PointUtf16::new(
2027                    info.location.range.start.line,
2028                    info.location.range.start.character,
2029                );
2030                let info_end = PointUtf16::new(
2031                    info.location.range.end.line,
2032                    info.location.range.end.character,
2033                );
2034                Some(info_start..info_end)
2035            } else {
2036                None
2037            }
2038        })
2039        .chain(Some(
2040            diagnostic.range.start.to_point_utf16()..diagnostic.range.end.to_point_utf16(),
2041        ))
2042}
2043
2044pub fn contiguous_ranges(
2045    values: impl Iterator<Item = u32>,
2046    max_len: usize,
2047) -> impl Iterator<Item = Range<u32>> {
2048    let mut values = values.into_iter();
2049    let mut current_range: Option<Range<u32>> = None;
2050    std::iter::from_fn(move || loop {
2051        if let Some(value) = values.next() {
2052            if let Some(range) = &mut current_range {
2053                if value == range.end && range.len() < max_len {
2054                    range.end += 1;
2055                    continue;
2056                }
2057            }
2058
2059            let prev_range = current_range.clone();
2060            current_range = Some(value..(value + 1));
2061            if prev_range.is_some() {
2062                return prev_range;
2063            }
2064        } else {
2065            return current_range.take();
2066        }
2067    })
2068}