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, LanguageScope, Outline,
  13};
  14use anyhow::{anyhow, Result};
  15use clock::ReplicaId;
  16use fs::LineEnding;
  17use futures::FutureExt as _;
  18use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, Task};
  19use lsp::LanguageServerId;
  20use parking_lot::Mutex;
  21use settings::Settings;
  22use similar::{ChangeTag, TextDiff};
  23use smallvec::SmallVec;
  24use smol::future::yield_now;
  25use std::{
  26    any::Any,
  27    cmp::{self, Ordering},
  28    collections::BTreeMap,
  29    ffi::OsStr,
  30    future::Future,
  31    iter::{self, Iterator, Peekable},
  32    mem,
  33    ops::{Deref, Range},
  34    path::{Path, PathBuf},
  35    str,
  36    sync::Arc,
  37    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  38    vec,
  39};
  40use sum_tree::TreeMap;
  41use text::operation_queue::OperationQueue;
  42pub use text::{Buffer as TextBuffer, BufferSnapshot as TextBufferSnapshot, *};
  43use theme::SyntaxTheme;
  44#[cfg(any(test, feature = "test-support"))]
  45use util::RandomCharIter;
  46use util::{RangeExt, TryFutureExt as _};
  47
  48#[cfg(any(test, feature = "test-support"))]
  49pub use {tree_sitter_rust, tree_sitter_typescript};
  50
  51pub use lsp::DiagnosticSeverity;
  52
  53struct GitDiffStatus {
  54    diff: git::diff::BufferDiff,
  55    update_in_progress: bool,
  56    update_requested: bool,
  57}
  58
  59pub struct Buffer {
  60    text: TextBuffer,
  61    diff_base: Option<String>,
  62    git_diff_status: GitDiffStatus,
  63    file: Option<Arc<dyn File>>,
  64    saved_version: clock::Global,
  65    saved_version_fingerprint: RopeFingerprint,
  66    saved_mtime: SystemTime,
  67    transaction_depth: usize,
  68    was_dirty_before_starting_transaction: Option<bool>,
  69    language: Option<Arc<Language>>,
  70    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  71    pending_autoindent: Option<Task<()>>,
  72    sync_parse_timeout: Duration,
  73    syntax_map: Mutex<SyntaxMap>,
  74    parsing_in_background: bool,
  75    parse_count: usize,
  76    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
  77    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  78    selections_update_count: usize,
  79    diagnostics_update_count: usize,
  80    diagnostics_timestamp: clock::Lamport,
  81    file_update_count: usize,
  82    git_diff_update_count: usize,
  83    completion_triggers: Vec<String>,
  84    completion_triggers_timestamp: clock::Lamport,
  85    deferred_ops: OperationQueue<Operation>,
  86}
  87
  88pub struct BufferSnapshot {
  89    text: text::BufferSnapshot,
  90    pub git_diff: git::diff::BufferDiff,
  91    pub(crate) syntax: SyntaxSnapshot,
  92    file: Option<Arc<dyn File>>,
  93    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
  94    diagnostics_update_count: usize,
  95    file_update_count: usize,
  96    git_diff_update_count: usize,
  97    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  98    selections_update_count: usize,
  99    language: Option<Arc<Language>>,
 100    parse_count: usize,
 101}
 102
 103#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 104pub struct IndentSize {
 105    pub len: u32,
 106    pub kind: IndentKind,
 107}
 108
 109#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 110pub enum IndentKind {
 111    #[default]
 112    Space,
 113    Tab,
 114}
 115
 116#[derive(Copy, Clone, PartialEq, Eq, Debug, Default)]
 117pub enum CursorShape {
 118    #[default]
 119    Bar,
 120    Block,
 121    Underscore,
 122    Hollow,
 123}
 124
 125#[derive(Clone, Debug)]
 126struct SelectionSet {
 127    line_mode: bool,
 128    cursor_shape: CursorShape,
 129    selections: Arc<[Selection<Anchor>]>,
 130    lamport_timestamp: clock::Lamport,
 131}
 132
 133#[derive(Clone, Debug, PartialEq, Eq)]
 134pub struct GroupId {
 135    source: Arc<str>,
 136    id: usize,
 137}
 138
 139#[derive(Clone, Debug, PartialEq, Eq)]
 140pub struct Diagnostic {
 141    pub source: Option<String>,
 142    pub code: Option<String>,
 143    pub severity: DiagnosticSeverity,
 144    pub message: String,
 145    pub group_id: usize,
 146    pub is_valid: bool,
 147    pub is_primary: bool,
 148    pub is_disk_based: bool,
 149    pub is_unnecessary: bool,
 150}
 151
 152#[derive(Clone, Debug)]
 153pub struct Completion {
 154    pub old_range: Range<Anchor>,
 155    pub new_text: String,
 156    pub label: CodeLabel,
 157    pub lsp_completion: lsp::CompletionItem,
 158}
 159
 160#[derive(Clone, Debug)]
 161pub struct CodeAction {
 162    pub server_id: LanguageServerId,
 163    pub range: Range<Anchor>,
 164    pub lsp_action: lsp::CodeAction,
 165}
 166
 167#[derive(Clone, Debug, PartialEq, Eq)]
 168pub enum Operation {
 169    Buffer(text::Operation),
 170
 171    UpdateDiagnostics {
 172        server_id: LanguageServerId,
 173        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 174        lamport_timestamp: clock::Lamport,
 175    },
 176
 177    UpdateSelections {
 178        selections: Arc<[Selection<Anchor>]>,
 179        lamport_timestamp: clock::Lamport,
 180        line_mode: bool,
 181        cursor_shape: CursorShape,
 182    },
 183
 184    UpdateCompletionTriggers {
 185        triggers: Vec<String>,
 186        lamport_timestamp: clock::Lamport,
 187    },
 188}
 189
 190#[derive(Clone, Debug, PartialEq, Eq)]
 191pub enum Event {
 192    Operation(Operation),
 193    Edited,
 194    DirtyChanged,
 195    Saved,
 196    FileHandleChanged,
 197    Reloaded,
 198    LanguageChanged,
 199    Reparsed,
 200    DiagnosticsUpdated,
 201    Closed,
 202}
 203
 204pub trait File: Send + Sync {
 205    fn as_local(&self) -> Option<&dyn LocalFile>;
 206
 207    fn is_local(&self) -> bool {
 208        self.as_local().is_some()
 209    }
 210
 211    fn mtime(&self) -> SystemTime;
 212
 213    /// Returns the path of this file relative to the worktree's root directory.
 214    fn path(&self) -> &Arc<Path>;
 215
 216    /// Returns the path of this file relative to the worktree's parent directory (this means it
 217    /// includes the name of the worktree's root folder).
 218    fn full_path(&self, cx: &AppContext) -> PathBuf;
 219
 220    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 221    /// of its worktree, then this method will return the name of the worktree itself.
 222    fn file_name<'a>(&'a self, cx: &'a AppContext) -> &'a OsStr;
 223
 224    fn is_deleted(&self) -> bool;
 225
 226    fn as_any(&self) -> &dyn Any;
 227
 228    fn to_proto(&self) -> rpc::proto::File;
 229}
 230
 231pub trait LocalFile: File {
 232    /// Returns the absolute path of this file.
 233    fn abs_path(&self, cx: &AppContext) -> PathBuf;
 234
 235    fn load(&self, cx: &AppContext) -> Task<Result<String>>;
 236
 237    fn buffer_reloaded(
 238        &self,
 239        buffer_id: u64,
 240        version: &clock::Global,
 241        fingerprint: RopeFingerprint,
 242        line_ending: LineEnding,
 243        mtime: SystemTime,
 244        cx: &mut AppContext,
 245    );
 246}
 247
 248#[derive(Clone, Debug)]
 249pub enum AutoindentMode {
 250    /// Indent each line of inserted text.
 251    EachLine,
 252    /// Apply the same indentation adjustment to all of the lines
 253    /// in a given insertion.
 254    Block {
 255        /// The original indentation level of the first line of each
 256        /// insertion, if it has been copied.
 257        original_indent_columns: Vec<u32>,
 258    },
 259}
 260
 261#[derive(Clone)]
 262struct AutoindentRequest {
 263    before_edit: BufferSnapshot,
 264    entries: Vec<AutoindentRequestEntry>,
 265    is_block_mode: bool,
 266}
 267
 268#[derive(Clone)]
 269struct AutoindentRequestEntry {
 270    /// A range of the buffer whose indentation should be adjusted.
 271    range: Range<Anchor>,
 272    /// Whether or not these lines should be considered brand new, for the
 273    /// purpose of auto-indent. When text is not new, its indentation will
 274    /// only be adjusted if the suggested indentation level has *changed*
 275    /// since the edit was made.
 276    first_line_is_new: bool,
 277    indent_size: IndentSize,
 278    original_indent_column: Option<u32>,
 279}
 280
 281#[derive(Debug)]
 282struct IndentSuggestion {
 283    basis_row: u32,
 284    delta: Ordering,
 285    within_error: bool,
 286}
 287
 288struct BufferChunkHighlights<'a> {
 289    captures: SyntaxMapCaptures<'a>,
 290    next_capture: Option<SyntaxMapCapture<'a>>,
 291    stack: Vec<(usize, HighlightId)>,
 292    highlight_maps: Vec<HighlightMap>,
 293}
 294
 295pub struct BufferChunks<'a> {
 296    range: Range<usize>,
 297    chunks: text::Chunks<'a>,
 298    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 299    error_depth: usize,
 300    warning_depth: usize,
 301    information_depth: usize,
 302    hint_depth: usize,
 303    unnecessary_depth: usize,
 304    highlights: Option<BufferChunkHighlights<'a>>,
 305}
 306
 307#[derive(Clone, Copy, Debug, Default)]
 308pub struct Chunk<'a> {
 309    pub text: &'a str,
 310    pub syntax_highlight_id: Option<HighlightId>,
 311    pub highlight_style: Option<HighlightStyle>,
 312    pub diagnostic_severity: Option<DiagnosticSeverity>,
 313    pub is_unnecessary: bool,
 314}
 315
 316pub struct Diff {
 317    pub(crate) base_version: clock::Global,
 318    line_ending: LineEnding,
 319    edits: Vec<(Range<usize>, Arc<str>)>,
 320}
 321
 322#[derive(Clone, Copy)]
 323pub(crate) struct DiagnosticEndpoint {
 324    offset: usize,
 325    is_start: bool,
 326    severity: DiagnosticSeverity,
 327    is_unnecessary: bool,
 328}
 329
 330#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 331pub enum CharKind {
 332    Punctuation,
 333    Whitespace,
 334    Word,
 335}
 336
 337impl CharKind {
 338    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 339        if treat_punctuation_as_word && self == CharKind::Punctuation {
 340            CharKind::Word
 341        } else {
 342            self
 343        }
 344    }
 345}
 346
 347impl Buffer {
 348    pub fn new<T: Into<String>>(
 349        replica_id: ReplicaId,
 350        base_text: T,
 351        cx: &mut ModelContext<Self>,
 352    ) -> Self {
 353        Self::build(
 354            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 355            None,
 356            None,
 357        )
 358    }
 359
 360    pub fn from_proto(
 361        replica_id: ReplicaId,
 362        message: proto::BufferState,
 363        file: Option<Arc<dyn File>>,
 364    ) -> Result<Self> {
 365        let buffer = TextBuffer::new(replica_id, message.id, message.base_text);
 366        let mut this = Self::build(
 367            buffer,
 368            message.diff_base.map(|text| text.into_boxed_str().into()),
 369            file,
 370        );
 371        this.text.set_line_ending(proto::deserialize_line_ending(
 372            rpc::proto::LineEnding::from_i32(message.line_ending)
 373                .ok_or_else(|| anyhow!("missing line_ending"))?,
 374        ));
 375        this.saved_version = proto::deserialize_version(&message.saved_version);
 376        this.saved_version_fingerprint =
 377            proto::deserialize_fingerprint(&message.saved_version_fingerprint)?;
 378        this.saved_mtime = message
 379            .saved_mtime
 380            .ok_or_else(|| anyhow!("invalid saved_mtime"))?
 381            .into();
 382        Ok(this)
 383    }
 384
 385    pub fn to_proto(&self) -> proto::BufferState {
 386        proto::BufferState {
 387            id: self.remote_id(),
 388            file: self.file.as_ref().map(|f| f.to_proto()),
 389            base_text: self.base_text().to_string(),
 390            diff_base: self.diff_base.as_ref().map(|h| h.to_string()),
 391            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 392            saved_version: proto::serialize_version(&self.saved_version),
 393            saved_version_fingerprint: proto::serialize_fingerprint(self.saved_version_fingerprint),
 394            saved_mtime: Some(self.saved_mtime.into()),
 395        }
 396    }
 397
 398    pub fn serialize_ops(
 399        &self,
 400        since: Option<clock::Global>,
 401        cx: &AppContext,
 402    ) -> Task<Vec<proto::Operation>> {
 403        let mut operations = Vec::new();
 404        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 405
 406        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 407            proto::serialize_operation(&Operation::UpdateSelections {
 408                selections: set.selections.clone(),
 409                lamport_timestamp: set.lamport_timestamp,
 410                line_mode: set.line_mode,
 411                cursor_shape: set.cursor_shape,
 412            })
 413        }));
 414
 415        for (server_id, diagnostics) in &self.diagnostics {
 416            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 417                lamport_timestamp: self.diagnostics_timestamp,
 418                server_id: *server_id,
 419                diagnostics: diagnostics.iter().cloned().collect(),
 420            }));
 421        }
 422
 423        operations.push(proto::serialize_operation(
 424            &Operation::UpdateCompletionTriggers {
 425                triggers: self.completion_triggers.clone(),
 426                lamport_timestamp: self.completion_triggers_timestamp,
 427            },
 428        ));
 429
 430        let text_operations = self.text.operations().clone();
 431        cx.background().spawn(async move {
 432            let since = since.unwrap_or_default();
 433            operations.extend(
 434                text_operations
 435                    .iter()
 436                    .filter(|(_, op)| !since.observed(op.local_timestamp()))
 437                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 438            );
 439            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 440            operations
 441        })
 442    }
 443
 444    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 445        self.set_language(Some(language), cx);
 446        self
 447    }
 448
 449    pub fn build(
 450        buffer: TextBuffer,
 451        diff_base: Option<String>,
 452        file: Option<Arc<dyn File>>,
 453    ) -> Self {
 454        let saved_mtime = if let Some(file) = file.as_ref() {
 455            file.mtime()
 456        } else {
 457            UNIX_EPOCH
 458        };
 459
 460        Self {
 461            saved_mtime,
 462            saved_version: buffer.version(),
 463            saved_version_fingerprint: buffer.as_rope().fingerprint(),
 464            transaction_depth: 0,
 465            was_dirty_before_starting_transaction: None,
 466            text: buffer,
 467            diff_base,
 468            git_diff_status: GitDiffStatus {
 469                diff: git::diff::BufferDiff::new(),
 470                update_in_progress: false,
 471                update_requested: false,
 472            },
 473            file,
 474            syntax_map: Mutex::new(SyntaxMap::new()),
 475            parsing_in_background: false,
 476            parse_count: 0,
 477            sync_parse_timeout: Duration::from_millis(1),
 478            autoindent_requests: Default::default(),
 479            pending_autoindent: Default::default(),
 480            language: None,
 481            remote_selections: Default::default(),
 482            selections_update_count: 0,
 483            diagnostics: Default::default(),
 484            diagnostics_update_count: 0,
 485            diagnostics_timestamp: Default::default(),
 486            file_update_count: 0,
 487            git_diff_update_count: 0,
 488            completion_triggers: Default::default(),
 489            completion_triggers_timestamp: Default::default(),
 490            deferred_ops: OperationQueue::new(),
 491        }
 492    }
 493
 494    pub fn snapshot(&self) -> BufferSnapshot {
 495        let text = self.text.snapshot();
 496        let mut syntax_map = self.syntax_map.lock();
 497        syntax_map.interpolate(&text);
 498        let syntax = syntax_map.snapshot();
 499
 500        BufferSnapshot {
 501            text,
 502            syntax,
 503            git_diff: self.git_diff_status.diff.clone(),
 504            file: self.file.clone(),
 505            remote_selections: self.remote_selections.clone(),
 506            diagnostics: self.diagnostics.clone(),
 507            diagnostics_update_count: self.diagnostics_update_count,
 508            file_update_count: self.file_update_count,
 509            git_diff_update_count: self.git_diff_update_count,
 510            language: self.language.clone(),
 511            parse_count: self.parse_count,
 512            selections_update_count: self.selections_update_count,
 513        }
 514    }
 515
 516    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 517        &self.text
 518    }
 519
 520    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 521        self.text.snapshot()
 522    }
 523
 524    pub fn file(&self) -> Option<&Arc<dyn File>> {
 525        self.file.as_ref()
 526    }
 527
 528    pub fn saved_version(&self) -> &clock::Global {
 529        &self.saved_version
 530    }
 531
 532    pub fn saved_version_fingerprint(&self) -> RopeFingerprint {
 533        self.saved_version_fingerprint
 534    }
 535
 536    pub fn saved_mtime(&self) -> SystemTime {
 537        self.saved_mtime
 538    }
 539
 540    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 541        self.syntax_map.lock().clear();
 542        self.language = language;
 543        self.reparse(cx);
 544        cx.emit(Event::LanguageChanged);
 545    }
 546
 547    pub fn set_language_registry(&mut self, language_registry: Arc<LanguageRegistry>) {
 548        self.syntax_map
 549            .lock()
 550            .set_language_registry(language_registry);
 551    }
 552
 553    pub fn did_save(
 554        &mut self,
 555        version: clock::Global,
 556        fingerprint: RopeFingerprint,
 557        mtime: SystemTime,
 558        cx: &mut ModelContext<Self>,
 559    ) {
 560        self.saved_version = version;
 561        self.saved_version_fingerprint = fingerprint;
 562        self.saved_mtime = mtime;
 563        cx.emit(Event::Saved);
 564        cx.notify();
 565    }
 566
 567    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 568        cx.spawn(|this, mut cx| async move {
 569            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 570                let file = this.file.as_ref()?.as_local()?;
 571                Some((file.mtime(), file.load(cx)))
 572            }) {
 573                let new_text = new_text.await?;
 574                let diff = this
 575                    .read_with(&cx, |this, cx| this.diff(new_text, cx))
 576                    .await;
 577                this.update(&mut cx, |this, cx| {
 578                    if this.version() == diff.base_version {
 579                        this.finalize_last_transaction();
 580                        this.apply_diff(diff, cx);
 581                        if let Some(transaction) = this.finalize_last_transaction().cloned() {
 582                            this.did_reload(
 583                                this.version(),
 584                                this.as_rope().fingerprint(),
 585                                this.line_ending(),
 586                                new_mtime,
 587                                cx,
 588                            );
 589                            return Ok(Some(transaction));
 590                        }
 591                    }
 592                    Ok(None)
 593                })
 594            } else {
 595                Ok(None)
 596            }
 597        })
 598    }
 599
 600    pub fn did_reload(
 601        &mut self,
 602        version: clock::Global,
 603        fingerprint: RopeFingerprint,
 604        line_ending: LineEnding,
 605        mtime: SystemTime,
 606        cx: &mut ModelContext<Self>,
 607    ) {
 608        self.saved_version = version;
 609        self.saved_version_fingerprint = fingerprint;
 610        self.text.set_line_ending(line_ending);
 611        self.saved_mtime = mtime;
 612        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 613            file.buffer_reloaded(
 614                self.remote_id(),
 615                &self.saved_version,
 616                self.saved_version_fingerprint,
 617                self.line_ending(),
 618                self.saved_mtime,
 619                cx,
 620            );
 621        }
 622        self.git_diff_recalc(cx);
 623        cx.emit(Event::Reloaded);
 624        cx.notify();
 625    }
 626
 627    pub fn file_updated(
 628        &mut self,
 629        new_file: Arc<dyn File>,
 630        cx: &mut ModelContext<Self>,
 631    ) -> Task<()> {
 632        let mut file_changed = false;
 633        let mut task = Task::ready(());
 634
 635        if let Some(old_file) = self.file.as_ref() {
 636            if new_file.path() != old_file.path() {
 637                file_changed = true;
 638            }
 639
 640            if new_file.is_deleted() {
 641                if !old_file.is_deleted() {
 642                    file_changed = true;
 643                    if !self.is_dirty() {
 644                        cx.emit(Event::DirtyChanged);
 645                    }
 646                }
 647            } else {
 648                let new_mtime = new_file.mtime();
 649                if new_mtime != old_file.mtime() {
 650                    file_changed = true;
 651
 652                    if !self.is_dirty() {
 653                        let reload = self.reload(cx).log_err().map(drop);
 654                        task = cx.foreground().spawn(reload);
 655                    }
 656                }
 657            }
 658        } else {
 659            file_changed = true;
 660        };
 661
 662        if file_changed {
 663            self.file_update_count += 1;
 664            cx.emit(Event::FileHandleChanged);
 665            cx.notify();
 666        }
 667        self.file = Some(new_file);
 668        task
 669    }
 670
 671    pub fn diff_base(&self) -> Option<&str> {
 672        self.diff_base.as_deref()
 673    }
 674
 675    pub fn set_diff_base(&mut self, diff_base: Option<String>, cx: &mut ModelContext<Self>) {
 676        self.diff_base = diff_base;
 677        self.git_diff_recalc(cx);
 678    }
 679
 680    pub fn needs_git_diff_recalc(&self) -> bool {
 681        self.git_diff_status.diff.needs_update(self)
 682    }
 683
 684    pub fn git_diff_recalc(&mut self, cx: &mut ModelContext<Self>) {
 685        if self.git_diff_status.update_in_progress {
 686            self.git_diff_status.update_requested = true;
 687            return;
 688        }
 689
 690        if let Some(diff_base) = &self.diff_base {
 691            let snapshot = self.snapshot();
 692            let diff_base = diff_base.clone();
 693
 694            let mut diff = self.git_diff_status.diff.clone();
 695            let diff = cx.background().spawn(async move {
 696                diff.update(&diff_base, &snapshot).await;
 697                diff
 698            });
 699
 700            cx.spawn_weak(|this, mut cx| async move {
 701                let buffer_diff = diff.await;
 702                if let Some(this) = this.upgrade(&cx) {
 703                    this.update(&mut cx, |this, cx| {
 704                        this.git_diff_status.diff = buffer_diff;
 705                        this.git_diff_update_count += 1;
 706                        cx.notify();
 707
 708                        this.git_diff_status.update_in_progress = false;
 709                        if this.git_diff_status.update_requested {
 710                            this.git_diff_recalc(cx);
 711                        }
 712                    })
 713                }
 714            })
 715            .detach()
 716        } else {
 717            let snapshot = self.snapshot();
 718            self.git_diff_status.diff.clear(&snapshot);
 719            self.git_diff_update_count += 1;
 720            cx.notify();
 721        }
 722    }
 723
 724    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 725        cx.emit(Event::Closed);
 726    }
 727
 728    pub fn language(&self) -> Option<&Arc<Language>> {
 729        self.language.as_ref()
 730    }
 731
 732    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
 733        let offset = position.to_offset(self);
 734        self.syntax_map
 735            .lock()
 736            .layers_for_range(offset..offset, &self.text)
 737            .last()
 738            .map(|info| info.language.clone())
 739            .or_else(|| self.language.clone())
 740    }
 741
 742    pub fn parse_count(&self) -> usize {
 743        self.parse_count
 744    }
 745
 746    pub fn selections_update_count(&self) -> usize {
 747        self.selections_update_count
 748    }
 749
 750    pub fn diagnostics_update_count(&self) -> usize {
 751        self.diagnostics_update_count
 752    }
 753
 754    pub fn file_update_count(&self) -> usize {
 755        self.file_update_count
 756    }
 757
 758    pub fn git_diff_update_count(&self) -> usize {
 759        self.git_diff_update_count
 760    }
 761
 762    #[cfg(any(test, feature = "test-support"))]
 763    pub fn is_parsing(&self) -> bool {
 764        self.parsing_in_background
 765    }
 766
 767    pub fn contains_unknown_injections(&self) -> bool {
 768        self.syntax_map.lock().contains_unknown_injections()
 769    }
 770
 771    #[cfg(test)]
 772    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 773        self.sync_parse_timeout = timeout;
 774    }
 775
 776    /// Called after an edit to synchronize the buffer's main parse tree with
 777    /// the buffer's new underlying state.
 778    ///
 779    /// Locks the syntax map and interpolates the edits since the last reparse
 780    /// into the foreground syntax tree.
 781    ///
 782    /// Then takes a stable snapshot of the syntax map before unlocking it.
 783    /// The snapshot with the interpolated edits is sent to a background thread,
 784    /// where we ask Tree-sitter to perform an incremental parse.
 785    ///
 786    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
 787    /// waiting on the parse to complete. As soon as it completes, we proceed
 788    /// synchronously, unless a 1ms timeout elapses.
 789    ///
 790    /// If we time out waiting on the parse, we spawn a second task waiting
 791    /// until the parse does complete and return with the interpolated tree still
 792    /// in the foreground. When the background parse completes, call back into
 793    /// the main thread and assign the foreground parse state.
 794    ///
 795    /// If the buffer or grammar changed since the start of the background parse,
 796    /// initiate an additional reparse recursively. To avoid concurrent parses
 797    /// for the same buffer, we only initiate a new parse if we are not already
 798    /// parsing in the background.
 799    pub fn reparse(&mut self, cx: &mut ModelContext<Self>) {
 800        if self.parsing_in_background {
 801            return;
 802        }
 803        let language = if let Some(language) = self.language.clone() {
 804            language
 805        } else {
 806            return;
 807        };
 808
 809        let text = self.text_snapshot();
 810        let parsed_version = self.version();
 811
 812        let mut syntax_map = self.syntax_map.lock();
 813        syntax_map.interpolate(&text);
 814        let language_registry = syntax_map.language_registry();
 815        let mut syntax_snapshot = syntax_map.snapshot();
 816        drop(syntax_map);
 817
 818        let parse_task = cx.background().spawn({
 819            let language = language.clone();
 820            let language_registry = language_registry.clone();
 821            async move {
 822                syntax_snapshot.reparse(&text, language_registry, language);
 823                syntax_snapshot
 824            }
 825        });
 826
 827        match cx
 828            .background()
 829            .block_with_timeout(self.sync_parse_timeout, parse_task)
 830        {
 831            Ok(new_syntax_snapshot) => {
 832                self.did_finish_parsing(new_syntax_snapshot, cx);
 833                return;
 834            }
 835            Err(parse_task) => {
 836                self.parsing_in_background = true;
 837                cx.spawn(move |this, mut cx| async move {
 838                    let new_syntax_map = parse_task.await;
 839                    this.update(&mut cx, move |this, cx| {
 840                        let grammar_changed =
 841                            this.language.as_ref().map_or(true, |current_language| {
 842                                !Arc::ptr_eq(&language, current_language)
 843                            });
 844                        let language_registry_changed = new_syntax_map
 845                            .contains_unknown_injections()
 846                            && language_registry.map_or(false, |registry| {
 847                                registry.version() != new_syntax_map.language_registry_version()
 848                            });
 849                        let parse_again = language_registry_changed
 850                            || grammar_changed
 851                            || this.version.changed_since(&parsed_version);
 852                        this.did_finish_parsing(new_syntax_map, cx);
 853                        this.parsing_in_background = false;
 854                        if parse_again {
 855                            this.reparse(cx);
 856                        }
 857                    });
 858                })
 859                .detach();
 860            }
 861        }
 862    }
 863
 864    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut ModelContext<Self>) {
 865        self.parse_count += 1;
 866        self.syntax_map.lock().did_parse(syntax_snapshot);
 867        self.request_autoindent(cx);
 868        cx.emit(Event::Reparsed);
 869        cx.notify();
 870    }
 871
 872    pub fn update_diagnostics(
 873        &mut self,
 874        server_id: LanguageServerId,
 875        diagnostics: DiagnosticSet,
 876        cx: &mut ModelContext<Self>,
 877    ) {
 878        let lamport_timestamp = self.text.lamport_clock.tick();
 879        let op = Operation::UpdateDiagnostics {
 880            server_id,
 881            diagnostics: diagnostics.iter().cloned().collect(),
 882            lamport_timestamp,
 883        };
 884        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
 885        self.send_operation(op, cx);
 886    }
 887
 888    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 889        if let Some(indent_sizes) = self.compute_autoindents() {
 890            let indent_sizes = cx.background().spawn(indent_sizes);
 891            match cx
 892                .background()
 893                .block_with_timeout(Duration::from_micros(500), indent_sizes)
 894            {
 895                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
 896                Err(indent_sizes) => {
 897                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 898                        let indent_sizes = indent_sizes.await;
 899                        this.update(&mut cx, |this, cx| {
 900                            this.apply_autoindents(indent_sizes, cx);
 901                        });
 902                    }));
 903                }
 904            }
 905        } else {
 906            self.autoindent_requests.clear();
 907        }
 908    }
 909
 910    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
 911        let max_rows_between_yields = 100;
 912        let snapshot = self.snapshot();
 913        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
 914            return None;
 915        }
 916
 917        let autoindent_requests = self.autoindent_requests.clone();
 918        Some(async move {
 919            let mut indent_sizes = BTreeMap::new();
 920            for request in autoindent_requests {
 921                // Resolve each edited range to its row in the current buffer and in the
 922                // buffer before this batch of edits.
 923                let mut row_ranges = Vec::new();
 924                let mut old_to_new_rows = BTreeMap::new();
 925                let mut language_indent_sizes_by_new_row = Vec::new();
 926                for entry in &request.entries {
 927                    let position = entry.range.start;
 928                    let new_row = position.to_point(&snapshot).row;
 929                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
 930                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
 931
 932                    if !entry.first_line_is_new {
 933                        let old_row = position.to_point(&request.before_edit).row;
 934                        old_to_new_rows.insert(old_row, new_row);
 935                    }
 936                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
 937                }
 938
 939                // Build a map containing the suggested indentation for each of the edited lines
 940                // with respect to the state of the buffer before these edits. This map is keyed
 941                // by the rows for these lines in the current state of the buffer.
 942                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
 943                let old_edited_ranges =
 944                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 945                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 946                let mut language_indent_size = IndentSize::default();
 947                for old_edited_range in old_edited_ranges {
 948                    let suggestions = request
 949                        .before_edit
 950                        .suggest_autoindents(old_edited_range.clone())
 951                        .into_iter()
 952                        .flatten();
 953                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 954                        if let Some(suggestion) = suggestion {
 955                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
 956
 957                            // Find the indent size based on the language for this row.
 958                            while let Some((row, size)) = language_indent_sizes.peek() {
 959                                if *row > new_row {
 960                                    break;
 961                                }
 962                                language_indent_size = *size;
 963                                language_indent_sizes.next();
 964                            }
 965
 966                            let suggested_indent = old_to_new_rows
 967                                .get(&suggestion.basis_row)
 968                                .and_then(|from_row| {
 969                                    Some(old_suggestions.get(from_row).copied()?.0)
 970                                })
 971                                .unwrap_or_else(|| {
 972                                    request
 973                                        .before_edit
 974                                        .indent_size_for_line(suggestion.basis_row)
 975                                })
 976                                .with_delta(suggestion.delta, language_indent_size);
 977                            old_suggestions
 978                                .insert(new_row, (suggested_indent, suggestion.within_error));
 979                        }
 980                    }
 981                    yield_now().await;
 982                }
 983
 984                // In block mode, only compute indentation suggestions for the first line
 985                // of each insertion. Otherwise, compute suggestions for every inserted line.
 986                let new_edited_row_ranges = contiguous_ranges(
 987                    row_ranges.iter().flat_map(|(range, _)| {
 988                        if request.is_block_mode {
 989                            range.start..range.start + 1
 990                        } else {
 991                            range.clone()
 992                        }
 993                    }),
 994                    max_rows_between_yields,
 995                );
 996
 997                // Compute new suggestions for each line, but only include them in the result
 998                // if they differ from the old suggestion for that line.
 999                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1000                let mut language_indent_size = IndentSize::default();
1001                for new_edited_row_range in new_edited_row_ranges {
1002                    let suggestions = snapshot
1003                        .suggest_autoindents(new_edited_row_range.clone())
1004                        .into_iter()
1005                        .flatten();
1006                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1007                        if let Some(suggestion) = suggestion {
1008                            // Find the indent size based on the language for this row.
1009                            while let Some((row, size)) = language_indent_sizes.peek() {
1010                                if *row > new_row {
1011                                    break;
1012                                }
1013                                language_indent_size = *size;
1014                                language_indent_sizes.next();
1015                            }
1016
1017                            let suggested_indent = indent_sizes
1018                                .get(&suggestion.basis_row)
1019                                .copied()
1020                                .unwrap_or_else(|| {
1021                                    snapshot.indent_size_for_line(suggestion.basis_row)
1022                                })
1023                                .with_delta(suggestion.delta, language_indent_size);
1024                            if old_suggestions.get(&new_row).map_or(
1025                                true,
1026                                |(old_indentation, was_within_error)| {
1027                                    suggested_indent != *old_indentation
1028                                        && (!suggestion.within_error || *was_within_error)
1029                                },
1030                            ) {
1031                                indent_sizes.insert(new_row, suggested_indent);
1032                            }
1033                        }
1034                    }
1035                    yield_now().await;
1036                }
1037
1038                // For each block of inserted text, adjust the indentation of the remaining
1039                // lines of the block by the same amount as the first line was adjusted.
1040                if request.is_block_mode {
1041                    for (row_range, original_indent_column) in
1042                        row_ranges
1043                            .into_iter()
1044                            .filter_map(|(range, original_indent_column)| {
1045                                if range.len() > 1 {
1046                                    Some((range, original_indent_column?))
1047                                } else {
1048                                    None
1049                                }
1050                            })
1051                    {
1052                        let new_indent = indent_sizes
1053                            .get(&row_range.start)
1054                            .copied()
1055                            .unwrap_or_else(|| snapshot.indent_size_for_line(row_range.start));
1056                        let delta = new_indent.len as i64 - original_indent_column as i64;
1057                        if delta != 0 {
1058                            for row in row_range.skip(1) {
1059                                indent_sizes.entry(row).or_insert_with(|| {
1060                                    let mut size = snapshot.indent_size_for_line(row);
1061                                    if size.kind == new_indent.kind {
1062                                        match delta.cmp(&0) {
1063                                            Ordering::Greater => size.len += delta as u32,
1064                                            Ordering::Less => {
1065                                                size.len = size.len.saturating_sub(-delta as u32)
1066                                            }
1067                                            Ordering::Equal => {}
1068                                        }
1069                                    }
1070                                    size
1071                                });
1072                            }
1073                        }
1074                    }
1075                }
1076            }
1077
1078            indent_sizes
1079        })
1080    }
1081
1082    fn apply_autoindents(
1083        &mut self,
1084        indent_sizes: BTreeMap<u32, IndentSize>,
1085        cx: &mut ModelContext<Self>,
1086    ) {
1087        self.autoindent_requests.clear();
1088
1089        let edits: Vec<_> = indent_sizes
1090            .into_iter()
1091            .filter_map(|(row, indent_size)| {
1092                let current_size = indent_size_for_line(self, row);
1093                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1094            })
1095            .collect();
1096
1097        self.edit(edits, None, cx);
1098    }
1099
1100    // Create a minimal edit that will cause the the given row to be indented
1101    // with the given size. After applying this edit, the length of the line
1102    // will always be at least `new_size.len`.
1103    pub fn edit_for_indent_size_adjustment(
1104        row: u32,
1105        current_size: IndentSize,
1106        new_size: IndentSize,
1107    ) -> Option<(Range<Point>, String)> {
1108        if new_size.kind != current_size.kind {
1109            Some((
1110                Point::new(row, 0)..Point::new(row, current_size.len),
1111                iter::repeat(new_size.char())
1112                    .take(new_size.len as usize)
1113                    .collect::<String>(),
1114            ))
1115        } else {
1116            match new_size.len.cmp(&current_size.len) {
1117                Ordering::Greater => {
1118                    let point = Point::new(row, 0);
1119                    Some((
1120                        point..point,
1121                        iter::repeat(new_size.char())
1122                            .take((new_size.len - current_size.len) as usize)
1123                            .collect::<String>(),
1124                    ))
1125                }
1126
1127                Ordering::Less => Some((
1128                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1129                    String::new(),
1130                )),
1131
1132                Ordering::Equal => None,
1133            }
1134        }
1135    }
1136
1137    pub fn diff(&self, mut new_text: String, cx: &AppContext) -> Task<Diff> {
1138        let old_text = self.as_rope().clone();
1139        let base_version = self.version();
1140        cx.background().spawn(async move {
1141            let old_text = old_text.to_string();
1142            let line_ending = LineEnding::detect(&new_text);
1143            LineEnding::normalize(&mut new_text);
1144            let diff = TextDiff::from_chars(old_text.as_str(), new_text.as_str());
1145            let mut edits = Vec::new();
1146            let mut offset = 0;
1147            let empty: Arc<str> = "".into();
1148            for change in diff.iter_all_changes() {
1149                let value = change.value();
1150                let end_offset = offset + value.len();
1151                match change.tag() {
1152                    ChangeTag::Equal => {
1153                        offset = end_offset;
1154                    }
1155                    ChangeTag::Delete => {
1156                        edits.push((offset..end_offset, empty.clone()));
1157                        offset = end_offset;
1158                    }
1159                    ChangeTag::Insert => {
1160                        edits.push((offset..offset, value.into()));
1161                    }
1162                }
1163            }
1164            Diff {
1165                base_version,
1166                line_ending,
1167                edits,
1168            }
1169        })
1170    }
1171
1172    /// Spawn a background task that searches the buffer for any whitespace
1173    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1174    pub fn remove_trailing_whitespace(&self, cx: &AppContext) -> Task<Diff> {
1175        let old_text = self.as_rope().clone();
1176        let line_ending = self.line_ending();
1177        let base_version = self.version();
1178        cx.background().spawn(async move {
1179            let ranges = trailing_whitespace_ranges(&old_text);
1180            let empty = Arc::<str>::from("");
1181            Diff {
1182                base_version,
1183                line_ending,
1184                edits: ranges
1185                    .into_iter()
1186                    .map(|range| (range, empty.clone()))
1187                    .collect(),
1188            }
1189        })
1190    }
1191
1192    /// Ensure that the buffer ends with a single newline character, and
1193    /// no other whitespace.
1194    pub fn ensure_final_newline(&mut self, cx: &mut ModelContext<Self>) {
1195        let len = self.len();
1196        let mut offset = len;
1197        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1198            let non_whitespace_len = chunk
1199                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1200                .len();
1201            offset -= chunk.len();
1202            offset += non_whitespace_len;
1203            if non_whitespace_len != 0 {
1204                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1205                    return;
1206                }
1207                break;
1208            }
1209        }
1210        self.edit([(offset..len, "\n")], None, cx);
1211    }
1212
1213    /// Apply a diff to the buffer. If the buffer has changed since the given diff was
1214    /// calculated, then adjust the diff to account for those changes, and discard any
1215    /// parts of the diff that conflict with those changes.
1216    pub fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1217        // Check for any edits to the buffer that have occurred since this diff
1218        // was computed.
1219        let snapshot = self.snapshot();
1220        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1221        let mut delta = 0;
1222        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1223            while let Some(edit_since) = edits_since.peek() {
1224                // If the edit occurs after a diff hunk, then it does not
1225                // affect that hunk.
1226                if edit_since.old.start > range.end {
1227                    break;
1228                }
1229                // If the edit precedes the diff hunk, then adjust the hunk
1230                // to reflect the edit.
1231                else if edit_since.old.end < range.start {
1232                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1233                    edits_since.next();
1234                }
1235                // If the edit intersects a diff hunk, then discard that hunk.
1236                else {
1237                    return None;
1238                }
1239            }
1240
1241            let start = (range.start as i64 + delta) as usize;
1242            let end = (range.end as i64 + delta) as usize;
1243            Some((start..end, new_text))
1244        });
1245
1246        self.start_transaction();
1247        self.text.set_line_ending(diff.line_ending);
1248        self.edit(adjusted_edits, None, cx);
1249        self.end_transaction(cx)
1250    }
1251
1252    pub fn is_dirty(&self) -> bool {
1253        self.saved_version_fingerprint != self.as_rope().fingerprint()
1254            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1255    }
1256
1257    pub fn has_conflict(&self) -> bool {
1258        self.saved_version_fingerprint != self.as_rope().fingerprint()
1259            && self
1260                .file
1261                .as_ref()
1262                .map_or(false, |file| file.mtime() > self.saved_mtime)
1263    }
1264
1265    pub fn subscribe(&mut self) -> Subscription {
1266        self.text.subscribe()
1267    }
1268
1269    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1270        self.start_transaction_at(Instant::now())
1271    }
1272
1273    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1274        self.transaction_depth += 1;
1275        if self.was_dirty_before_starting_transaction.is_none() {
1276            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1277        }
1278        self.text.start_transaction_at(now)
1279    }
1280
1281    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1282        self.end_transaction_at(Instant::now(), cx)
1283    }
1284
1285    pub fn end_transaction_at(
1286        &mut self,
1287        now: Instant,
1288        cx: &mut ModelContext<Self>,
1289    ) -> Option<TransactionId> {
1290        assert!(self.transaction_depth > 0);
1291        self.transaction_depth -= 1;
1292        let was_dirty = if self.transaction_depth == 0 {
1293            self.was_dirty_before_starting_transaction.take().unwrap()
1294        } else {
1295            false
1296        };
1297        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1298            self.did_edit(&start_version, was_dirty, cx);
1299            Some(transaction_id)
1300        } else {
1301            None
1302        }
1303    }
1304
1305    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1306        self.text.push_transaction(transaction, now);
1307    }
1308
1309    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1310        self.text.finalize_last_transaction()
1311    }
1312
1313    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1314        self.text.group_until_transaction(transaction_id);
1315    }
1316
1317    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1318        self.text.forget_transaction(transaction_id);
1319    }
1320
1321    pub fn wait_for_edits(
1322        &mut self,
1323        edit_ids: impl IntoIterator<Item = clock::Local>,
1324    ) -> impl Future<Output = Result<()>> {
1325        self.text.wait_for_edits(edit_ids)
1326    }
1327
1328    pub fn wait_for_anchors(
1329        &mut self,
1330        anchors: impl IntoIterator<Item = Anchor>,
1331    ) -> impl 'static + Future<Output = Result<()>> {
1332        self.text.wait_for_anchors(anchors)
1333    }
1334
1335    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = Result<()>> {
1336        self.text.wait_for_version(version)
1337    }
1338
1339    pub fn give_up_waiting(&mut self) {
1340        self.text.give_up_waiting();
1341    }
1342
1343    pub fn set_active_selections(
1344        &mut self,
1345        selections: Arc<[Selection<Anchor>]>,
1346        line_mode: bool,
1347        cursor_shape: CursorShape,
1348        cx: &mut ModelContext<Self>,
1349    ) {
1350        let lamport_timestamp = self.text.lamport_clock.tick();
1351        self.remote_selections.insert(
1352            self.text.replica_id(),
1353            SelectionSet {
1354                selections: selections.clone(),
1355                lamport_timestamp,
1356                line_mode,
1357                cursor_shape,
1358            },
1359        );
1360        self.send_operation(
1361            Operation::UpdateSelections {
1362                selections,
1363                line_mode,
1364                lamport_timestamp,
1365                cursor_shape,
1366            },
1367            cx,
1368        );
1369    }
1370
1371    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1372        if self
1373            .remote_selections
1374            .get(&self.text.replica_id())
1375            .map_or(true, |set| !set.selections.is_empty())
1376        {
1377            self.set_active_selections(Arc::from([]), false, Default::default(), cx);
1378        }
1379    }
1380
1381    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1382    where
1383        T: Into<Arc<str>>,
1384    {
1385        self.autoindent_requests.clear();
1386        self.edit([(0..self.len(), text)], None, cx)
1387    }
1388
1389    pub fn edit<I, S, T>(
1390        &mut self,
1391        edits_iter: I,
1392        autoindent_mode: Option<AutoindentMode>,
1393        cx: &mut ModelContext<Self>,
1394    ) -> Option<clock::Local>
1395    where
1396        I: IntoIterator<Item = (Range<S>, T)>,
1397        S: ToOffset,
1398        T: Into<Arc<str>>,
1399    {
1400        // Skip invalid edits and coalesce contiguous ones.
1401        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1402        for (range, new_text) in edits_iter {
1403            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
1404            if range.start > range.end {
1405                mem::swap(&mut range.start, &mut range.end);
1406            }
1407            let new_text = new_text.into();
1408            if !new_text.is_empty() || !range.is_empty() {
1409                if let Some((prev_range, prev_text)) = edits.last_mut() {
1410                    if prev_range.end >= range.start {
1411                        prev_range.end = cmp::max(prev_range.end, range.end);
1412                        *prev_text = format!("{prev_text}{new_text}").into();
1413                    } else {
1414                        edits.push((range, new_text));
1415                    }
1416                } else {
1417                    edits.push((range, new_text));
1418                }
1419            }
1420        }
1421        if edits.is_empty() {
1422            return None;
1423        }
1424
1425        self.start_transaction();
1426        self.pending_autoindent.take();
1427        let autoindent_request = autoindent_mode
1428            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
1429
1430        let edit_operation = self.text.edit(edits.iter().cloned());
1431        let edit_id = edit_operation.local_timestamp();
1432
1433        if let Some((before_edit, mode)) = autoindent_request {
1434            let mut delta = 0isize;
1435            let entries = edits
1436                .into_iter()
1437                .enumerate()
1438                .zip(&edit_operation.as_edit().unwrap().new_text)
1439                .map(|((ix, (range, _)), new_text)| {
1440                    let new_text_length = new_text.len();
1441                    let old_start = range.start.to_point(&before_edit);
1442                    let new_start = (delta + range.start as isize) as usize;
1443                    delta += new_text_length as isize - (range.end as isize - range.start as isize);
1444
1445                    let mut range_of_insertion_to_indent = 0..new_text_length;
1446                    let mut first_line_is_new = false;
1447                    let mut original_indent_column = None;
1448
1449                    // When inserting an entire line at the beginning of an existing line,
1450                    // treat the insertion as new.
1451                    if new_text.contains('\n')
1452                        && old_start.column <= before_edit.indent_size_for_line(old_start.row).len
1453                    {
1454                        first_line_is_new = true;
1455                    }
1456
1457                    // When inserting text starting with a newline, avoid auto-indenting the
1458                    // previous line.
1459                    if new_text.starts_with('\n') {
1460                        range_of_insertion_to_indent.start += 1;
1461                        first_line_is_new = true;
1462                    }
1463
1464                    // Avoid auto-indenting after the insertion.
1465                    if let AutoindentMode::Block {
1466                        original_indent_columns,
1467                    } = &mode
1468                    {
1469                        original_indent_column =
1470                            Some(original_indent_columns.get(ix).copied().unwrap_or_else(|| {
1471                                indent_size_for_text(
1472                                    new_text[range_of_insertion_to_indent.clone()].chars(),
1473                                )
1474                                .len
1475                            }));
1476                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
1477                            range_of_insertion_to_indent.end -= 1;
1478                        }
1479                    }
1480
1481                    AutoindentRequestEntry {
1482                        first_line_is_new,
1483                        original_indent_column,
1484                        indent_size: before_edit.language_indent_size_at(range.start, cx),
1485                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
1486                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
1487                    }
1488                })
1489                .collect();
1490
1491            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1492                before_edit,
1493                entries,
1494                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
1495            }));
1496        }
1497
1498        self.end_transaction(cx);
1499        self.send_operation(Operation::Buffer(edit_operation), cx);
1500        Some(edit_id)
1501    }
1502
1503    fn did_edit(
1504        &mut self,
1505        old_version: &clock::Global,
1506        was_dirty: bool,
1507        cx: &mut ModelContext<Self>,
1508    ) {
1509        if self.edits_since::<usize>(old_version).next().is_none() {
1510            return;
1511        }
1512
1513        self.reparse(cx);
1514
1515        cx.emit(Event::Edited);
1516        if was_dirty != self.is_dirty() {
1517            cx.emit(Event::DirtyChanged);
1518        }
1519        cx.notify();
1520    }
1521
1522    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1523        &mut self,
1524        ops: I,
1525        cx: &mut ModelContext<Self>,
1526    ) -> Result<()> {
1527        self.pending_autoindent.take();
1528        let was_dirty = self.is_dirty();
1529        let old_version = self.version.clone();
1530        let mut deferred_ops = Vec::new();
1531        let buffer_ops = ops
1532            .into_iter()
1533            .filter_map(|op| match op {
1534                Operation::Buffer(op) => Some(op),
1535                _ => {
1536                    if self.can_apply_op(&op) {
1537                        self.apply_op(op, cx);
1538                    } else {
1539                        deferred_ops.push(op);
1540                    }
1541                    None
1542                }
1543            })
1544            .collect::<Vec<_>>();
1545        self.text.apply_ops(buffer_ops)?;
1546        self.deferred_ops.insert(deferred_ops);
1547        self.flush_deferred_ops(cx);
1548        self.did_edit(&old_version, was_dirty, cx);
1549        // Notify independently of whether the buffer was edited as the operations could include a
1550        // selection update.
1551        cx.notify();
1552        Ok(())
1553    }
1554
1555    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1556        let mut deferred_ops = Vec::new();
1557        for op in self.deferred_ops.drain().iter().cloned() {
1558            if self.can_apply_op(&op) {
1559                self.apply_op(op, cx);
1560            } else {
1561                deferred_ops.push(op);
1562            }
1563        }
1564        self.deferred_ops.insert(deferred_ops);
1565    }
1566
1567    fn can_apply_op(&self, operation: &Operation) -> bool {
1568        match operation {
1569            Operation::Buffer(_) => {
1570                unreachable!("buffer operations should never be applied at this layer")
1571            }
1572            Operation::UpdateDiagnostics {
1573                diagnostics: diagnostic_set,
1574                ..
1575            } => diagnostic_set.iter().all(|diagnostic| {
1576                self.text.can_resolve(&diagnostic.range.start)
1577                    && self.text.can_resolve(&diagnostic.range.end)
1578            }),
1579            Operation::UpdateSelections { selections, .. } => selections
1580                .iter()
1581                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1582            Operation::UpdateCompletionTriggers { .. } => true,
1583        }
1584    }
1585
1586    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1587        match operation {
1588            Operation::Buffer(_) => {
1589                unreachable!("buffer operations should never be applied at this layer")
1590            }
1591            Operation::UpdateDiagnostics {
1592                server_id,
1593                diagnostics: diagnostic_set,
1594                lamport_timestamp,
1595            } => {
1596                let snapshot = self.snapshot();
1597                self.apply_diagnostic_update(
1598                    server_id,
1599                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1600                    lamport_timestamp,
1601                    cx,
1602                );
1603            }
1604            Operation::UpdateSelections {
1605                selections,
1606                lamport_timestamp,
1607                line_mode,
1608                cursor_shape,
1609            } => {
1610                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1611                    if set.lamport_timestamp > lamport_timestamp {
1612                        return;
1613                    }
1614                }
1615
1616                self.remote_selections.insert(
1617                    lamport_timestamp.replica_id,
1618                    SelectionSet {
1619                        selections,
1620                        lamport_timestamp,
1621                        line_mode,
1622                        cursor_shape,
1623                    },
1624                );
1625                self.text.lamport_clock.observe(lamport_timestamp);
1626                self.selections_update_count += 1;
1627            }
1628            Operation::UpdateCompletionTriggers {
1629                triggers,
1630                lamport_timestamp,
1631            } => {
1632                self.completion_triggers = triggers;
1633                self.text.lamport_clock.observe(lamport_timestamp);
1634            }
1635        }
1636    }
1637
1638    fn apply_diagnostic_update(
1639        &mut self,
1640        server_id: LanguageServerId,
1641        diagnostics: DiagnosticSet,
1642        lamport_timestamp: clock::Lamport,
1643        cx: &mut ModelContext<Self>,
1644    ) {
1645        if lamport_timestamp > self.diagnostics_timestamp {
1646            match self.diagnostics.binary_search_by_key(&server_id, |e| e.0) {
1647                Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
1648                Ok(ix) => self.diagnostics[ix].1 = diagnostics,
1649            };
1650            self.diagnostics_timestamp = lamport_timestamp;
1651            self.diagnostics_update_count += 1;
1652            self.text.lamport_clock.observe(lamport_timestamp);
1653            cx.notify();
1654            cx.emit(Event::DiagnosticsUpdated);
1655        }
1656    }
1657
1658    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1659        cx.emit(Event::Operation(operation));
1660    }
1661
1662    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1663        self.remote_selections.remove(&replica_id);
1664        cx.notify();
1665    }
1666
1667    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1668        let was_dirty = self.is_dirty();
1669        let old_version = self.version.clone();
1670
1671        if let Some((transaction_id, operation)) = self.text.undo() {
1672            self.send_operation(Operation::Buffer(operation), cx);
1673            self.did_edit(&old_version, was_dirty, cx);
1674            Some(transaction_id)
1675        } else {
1676            None
1677        }
1678    }
1679
1680    pub fn undo_to_transaction(
1681        &mut self,
1682        transaction_id: TransactionId,
1683        cx: &mut ModelContext<Self>,
1684    ) -> bool {
1685        let was_dirty = self.is_dirty();
1686        let old_version = self.version.clone();
1687
1688        let operations = self.text.undo_to_transaction(transaction_id);
1689        let undone = !operations.is_empty();
1690        for operation in operations {
1691            self.send_operation(Operation::Buffer(operation), cx);
1692        }
1693        if undone {
1694            self.did_edit(&old_version, was_dirty, cx)
1695        }
1696        undone
1697    }
1698
1699    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1700        let was_dirty = self.is_dirty();
1701        let old_version = self.version.clone();
1702
1703        if let Some((transaction_id, operation)) = self.text.redo() {
1704            self.send_operation(Operation::Buffer(operation), cx);
1705            self.did_edit(&old_version, was_dirty, cx);
1706            Some(transaction_id)
1707        } else {
1708            None
1709        }
1710    }
1711
1712    pub fn redo_to_transaction(
1713        &mut self,
1714        transaction_id: TransactionId,
1715        cx: &mut ModelContext<Self>,
1716    ) -> bool {
1717        let was_dirty = self.is_dirty();
1718        let old_version = self.version.clone();
1719
1720        let operations = self.text.redo_to_transaction(transaction_id);
1721        let redone = !operations.is_empty();
1722        for operation in operations {
1723            self.send_operation(Operation::Buffer(operation), cx);
1724        }
1725        if redone {
1726            self.did_edit(&old_version, was_dirty, cx)
1727        }
1728        redone
1729    }
1730
1731    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1732        self.completion_triggers = triggers.clone();
1733        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
1734        self.send_operation(
1735            Operation::UpdateCompletionTriggers {
1736                triggers,
1737                lamport_timestamp: self.completion_triggers_timestamp,
1738            },
1739            cx,
1740        );
1741        cx.notify();
1742    }
1743
1744    pub fn completion_triggers(&self) -> &[String] {
1745        &self.completion_triggers
1746    }
1747}
1748
1749#[cfg(any(test, feature = "test-support"))]
1750impl Buffer {
1751    pub fn edit_via_marked_text(
1752        &mut self,
1753        marked_string: &str,
1754        autoindent_mode: Option<AutoindentMode>,
1755        cx: &mut ModelContext<Self>,
1756    ) {
1757        let edits = self.edits_for_marked_text(marked_string);
1758        self.edit(edits, autoindent_mode, cx);
1759    }
1760
1761    pub fn set_group_interval(&mut self, group_interval: Duration) {
1762        self.text.set_group_interval(group_interval);
1763    }
1764
1765    pub fn randomly_edit<T>(
1766        &mut self,
1767        rng: &mut T,
1768        old_range_count: usize,
1769        cx: &mut ModelContext<Self>,
1770    ) where
1771        T: rand::Rng,
1772    {
1773        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
1774        let mut last_end = None;
1775        for _ in 0..old_range_count {
1776            if last_end.map_or(false, |last_end| last_end >= self.len()) {
1777                break;
1778            }
1779
1780            let new_start = last_end.map_or(0, |last_end| last_end + 1);
1781            let mut range = self.random_byte_range(new_start, rng);
1782            if rng.gen_bool(0.2) {
1783                mem::swap(&mut range.start, &mut range.end);
1784            }
1785            last_end = Some(range.end);
1786
1787            let new_text_len = rng.gen_range(0..10);
1788            let new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
1789
1790            edits.push((range, new_text));
1791        }
1792        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
1793        self.edit(edits, None, cx);
1794    }
1795
1796    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1797        let was_dirty = self.is_dirty();
1798        let old_version = self.version.clone();
1799
1800        let ops = self.text.randomly_undo_redo(rng);
1801        if !ops.is_empty() {
1802            for op in ops {
1803                self.send_operation(Operation::Buffer(op), cx);
1804                self.did_edit(&old_version, was_dirty, cx);
1805            }
1806        }
1807    }
1808}
1809
1810impl Entity for Buffer {
1811    type Event = Event;
1812}
1813
1814impl Deref for Buffer {
1815    type Target = TextBuffer;
1816
1817    fn deref(&self) -> &Self::Target {
1818        &self.text
1819    }
1820}
1821
1822impl BufferSnapshot {
1823    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
1824        indent_size_for_line(self, row)
1825    }
1826
1827    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &AppContext) -> IndentSize {
1828        let language_name = self.language_at(position).map(|language| language.name());
1829        let settings = cx.global::<Settings>();
1830        if settings.hard_tabs(language_name.as_deref()) {
1831            IndentSize::tab()
1832        } else {
1833            IndentSize::spaces(settings.tab_size(language_name.as_deref()).get())
1834        }
1835    }
1836
1837    pub fn suggested_indents(
1838        &self,
1839        rows: impl Iterator<Item = u32>,
1840        single_indent_size: IndentSize,
1841    ) -> BTreeMap<u32, IndentSize> {
1842        let mut result = BTreeMap::new();
1843
1844        for row_range in contiguous_ranges(rows, 10) {
1845            let suggestions = match self.suggest_autoindents(row_range.clone()) {
1846                Some(suggestions) => suggestions,
1847                _ => break,
1848            };
1849
1850            for (row, suggestion) in row_range.zip(suggestions) {
1851                let indent_size = if let Some(suggestion) = suggestion {
1852                    result
1853                        .get(&suggestion.basis_row)
1854                        .copied()
1855                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
1856                        .with_delta(suggestion.delta, single_indent_size)
1857                } else {
1858                    self.indent_size_for_line(row)
1859                };
1860
1861                result.insert(row, indent_size);
1862            }
1863        }
1864
1865        result
1866    }
1867
1868    fn suggest_autoindents(
1869        &self,
1870        row_range: Range<u32>,
1871    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
1872        let config = &self.language.as_ref()?.config;
1873        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1874
1875        // Find the suggested indentation ranges based on the syntax tree.
1876        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
1877        let end = Point::new(row_range.end, 0);
1878        let range = (start..end).to_offset(&self.text);
1879        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1880            Some(&grammar.indents_config.as_ref()?.query)
1881        });
1882        let indent_configs = matches
1883            .grammars()
1884            .iter()
1885            .map(|grammar| grammar.indents_config.as_ref().unwrap())
1886            .collect::<Vec<_>>();
1887
1888        let mut indent_ranges = Vec::<Range<Point>>::new();
1889        let mut outdent_positions = Vec::<Point>::new();
1890        while let Some(mat) = matches.peek() {
1891            let mut start: Option<Point> = None;
1892            let mut end: Option<Point> = None;
1893
1894            let config = &indent_configs[mat.grammar_index];
1895            for capture in mat.captures {
1896                if capture.index == config.indent_capture_ix {
1897                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1898                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1899                } else if Some(capture.index) == config.start_capture_ix {
1900                    start = Some(Point::from_ts_point(capture.node.end_position()));
1901                } else if Some(capture.index) == config.end_capture_ix {
1902                    end = Some(Point::from_ts_point(capture.node.start_position()));
1903                } else if Some(capture.index) == config.outdent_capture_ix {
1904                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
1905                }
1906            }
1907
1908            matches.advance();
1909            if let Some((start, end)) = start.zip(end) {
1910                if start.row == end.row {
1911                    continue;
1912                }
1913
1914                let range = start..end;
1915                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
1916                    Err(ix) => indent_ranges.insert(ix, range),
1917                    Ok(ix) => {
1918                        let prev_range = &mut indent_ranges[ix];
1919                        prev_range.end = prev_range.end.max(range.end);
1920                    }
1921                }
1922            }
1923        }
1924
1925        let mut error_ranges = Vec::<Range<Point>>::new();
1926        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1927            Some(&grammar.error_query)
1928        });
1929        while let Some(mat) = matches.peek() {
1930            let node = mat.captures[0].node;
1931            let start = Point::from_ts_point(node.start_position());
1932            let end = Point::from_ts_point(node.end_position());
1933            let range = start..end;
1934            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
1935                Ok(ix) | Err(ix) => ix,
1936            };
1937            let mut end_ix = ix;
1938            while let Some(existing_range) = error_ranges.get(end_ix) {
1939                if existing_range.end < end {
1940                    end_ix += 1;
1941                } else {
1942                    break;
1943                }
1944            }
1945            error_ranges.splice(ix..end_ix, [range]);
1946            matches.advance();
1947        }
1948
1949        outdent_positions.sort();
1950        for outdent_position in outdent_positions {
1951            // find the innermost indent range containing this outdent_position
1952            // set its end to the outdent position
1953            if let Some(range_to_truncate) = indent_ranges
1954                .iter_mut()
1955                .filter(|indent_range| indent_range.contains(&outdent_position))
1956                .last()
1957            {
1958                range_to_truncate.end = outdent_position;
1959            }
1960        }
1961
1962        // Find the suggested indentation increases and decreased based on regexes.
1963        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
1964        self.for_each_line(
1965            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
1966                ..Point::new(row_range.end, 0),
1967            |row, line| {
1968                if config
1969                    .decrease_indent_pattern
1970                    .as_ref()
1971                    .map_or(false, |regex| regex.is_match(line))
1972                {
1973                    indent_change_rows.push((row, Ordering::Less));
1974                }
1975                if config
1976                    .increase_indent_pattern
1977                    .as_ref()
1978                    .map_or(false, |regex| regex.is_match(line))
1979                {
1980                    indent_change_rows.push((row + 1, Ordering::Greater));
1981                }
1982            },
1983        );
1984
1985        let mut indent_changes = indent_change_rows.into_iter().peekable();
1986        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
1987            prev_non_blank_row.unwrap_or(0)
1988        } else {
1989            row_range.start.saturating_sub(1)
1990        };
1991        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
1992        Some(row_range.map(move |row| {
1993            let row_start = Point::new(row, self.indent_size_for_line(row).len);
1994
1995            let mut indent_from_prev_row = false;
1996            let mut outdent_from_prev_row = false;
1997            let mut outdent_to_row = u32::MAX;
1998
1999            while let Some((indent_row, delta)) = indent_changes.peek() {
2000                match indent_row.cmp(&row) {
2001                    Ordering::Equal => match delta {
2002                        Ordering::Less => outdent_from_prev_row = true,
2003                        Ordering::Greater => indent_from_prev_row = true,
2004                        _ => {}
2005                    },
2006
2007                    Ordering::Greater => break,
2008                    Ordering::Less => {}
2009                }
2010
2011                indent_changes.next();
2012            }
2013
2014            for range in &indent_ranges {
2015                if range.start.row >= row {
2016                    break;
2017                }
2018                if range.start.row == prev_row && range.end > row_start {
2019                    indent_from_prev_row = true;
2020                }
2021                if range.end > prev_row_start && range.end <= row_start {
2022                    outdent_to_row = outdent_to_row.min(range.start.row);
2023                }
2024            }
2025
2026            let within_error = error_ranges
2027                .iter()
2028                .any(|e| e.start.row < row && e.end > row_start);
2029
2030            let suggestion = if outdent_to_row == prev_row
2031                || (outdent_from_prev_row && indent_from_prev_row)
2032            {
2033                Some(IndentSuggestion {
2034                    basis_row: prev_row,
2035                    delta: Ordering::Equal,
2036                    within_error,
2037                })
2038            } else if indent_from_prev_row {
2039                Some(IndentSuggestion {
2040                    basis_row: prev_row,
2041                    delta: Ordering::Greater,
2042                    within_error,
2043                })
2044            } else if outdent_to_row < prev_row {
2045                Some(IndentSuggestion {
2046                    basis_row: outdent_to_row,
2047                    delta: Ordering::Equal,
2048                    within_error,
2049                })
2050            } else if outdent_from_prev_row {
2051                Some(IndentSuggestion {
2052                    basis_row: prev_row,
2053                    delta: Ordering::Less,
2054                    within_error,
2055                })
2056            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
2057            {
2058                Some(IndentSuggestion {
2059                    basis_row: prev_row,
2060                    delta: Ordering::Equal,
2061                    within_error,
2062                })
2063            } else {
2064                None
2065            };
2066
2067            prev_row = row;
2068            prev_row_start = row_start;
2069            suggestion
2070        }))
2071    }
2072
2073    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
2074        while row > 0 {
2075            row -= 1;
2076            if !self.is_line_blank(row) {
2077                return Some(row);
2078            }
2079        }
2080        None
2081    }
2082
2083    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
2084        let range = range.start.to_offset(self)..range.end.to_offset(self);
2085
2086        let mut syntax = None;
2087        let mut diagnostic_endpoints = Vec::new();
2088        if language_aware {
2089            let captures = self.syntax.captures(range.clone(), &self.text, |grammar| {
2090                grammar.highlights_query.as_ref()
2091            });
2092            let highlight_maps = captures
2093                .grammars()
2094                .into_iter()
2095                .map(|grammar| grammar.highlight_map())
2096                .collect();
2097            syntax = Some((captures, highlight_maps));
2098            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
2099                diagnostic_endpoints.push(DiagnosticEndpoint {
2100                    offset: entry.range.start,
2101                    is_start: true,
2102                    severity: entry.diagnostic.severity,
2103                    is_unnecessary: entry.diagnostic.is_unnecessary,
2104                });
2105                diagnostic_endpoints.push(DiagnosticEndpoint {
2106                    offset: entry.range.end,
2107                    is_start: false,
2108                    severity: entry.diagnostic.severity,
2109                    is_unnecessary: entry.diagnostic.is_unnecessary,
2110                });
2111            }
2112            diagnostic_endpoints
2113                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
2114        }
2115
2116        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostic_endpoints)
2117    }
2118
2119    pub fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
2120        let mut line = String::new();
2121        let mut row = range.start.row;
2122        for chunk in self
2123            .as_rope()
2124            .chunks_in_range(range.to_offset(self))
2125            .chain(["\n"])
2126        {
2127            for (newline_ix, text) in chunk.split('\n').enumerate() {
2128                if newline_ix > 0 {
2129                    callback(row, &line);
2130                    row += 1;
2131                    line.clear();
2132                }
2133                line.push_str(text);
2134            }
2135        }
2136    }
2137
2138    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
2139        let offset = position.to_offset(self);
2140        self.syntax
2141            .layers_for_range(offset..offset, &self.text)
2142            .filter(|l| l.node.end_byte() > offset)
2143            .last()
2144            .map(|info| info.language)
2145            .or(self.language.as_ref())
2146    }
2147
2148    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
2149        let offset = position.to_offset(self);
2150
2151        if let Some(layer_info) = self
2152            .syntax
2153            .layers_for_range(offset..offset, &self.text)
2154            .filter(|l| l.node.end_byte() > offset)
2155            .last()
2156        {
2157            Some(LanguageScope {
2158                language: layer_info.language.clone(),
2159                override_id: layer_info.override_id(offset, &self.text),
2160            })
2161        } else {
2162            self.language.clone().map(|language| LanguageScope {
2163                language,
2164                override_id: None,
2165            })
2166        }
2167    }
2168
2169    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
2170        let mut start = start.to_offset(self);
2171        let mut end = start;
2172        let mut next_chars = self.chars_at(start).peekable();
2173        let mut prev_chars = self.reversed_chars_at(start).peekable();
2174        let word_kind = cmp::max(
2175            prev_chars.peek().copied().map(char_kind),
2176            next_chars.peek().copied().map(char_kind),
2177        );
2178
2179        for ch in prev_chars {
2180            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2181                start -= ch.len_utf8();
2182            } else {
2183                break;
2184            }
2185        }
2186
2187        for ch in next_chars {
2188            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2189                end += ch.len_utf8();
2190            } else {
2191                break;
2192            }
2193        }
2194
2195        (start..end, word_kind)
2196    }
2197
2198    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
2199        let range = range.start.to_offset(self)..range.end.to_offset(self);
2200        let mut result: Option<Range<usize>> = None;
2201        'outer: for layer in self.syntax.layers_for_range(range.clone(), &self.text) {
2202            let mut cursor = layer.node.walk();
2203
2204            // Descend to the first leaf that touches the start of the range,
2205            // and if the range is non-empty, extends beyond the start.
2206            while cursor.goto_first_child_for_byte(range.start).is_some() {
2207                if !range.is_empty() && cursor.node().end_byte() == range.start {
2208                    cursor.goto_next_sibling();
2209                }
2210            }
2211
2212            // Ascend to the smallest ancestor that strictly contains the range.
2213            loop {
2214                let node_range = cursor.node().byte_range();
2215                if node_range.start <= range.start
2216                    && node_range.end >= range.end
2217                    && node_range.len() > range.len()
2218                {
2219                    break;
2220                }
2221                if !cursor.goto_parent() {
2222                    continue 'outer;
2223                }
2224            }
2225
2226            let left_node = cursor.node();
2227            let mut layer_result = left_node.byte_range();
2228
2229            // For an empty range, try to find another node immediately to the right of the range.
2230            if left_node.end_byte() == range.start {
2231                let mut right_node = None;
2232                while !cursor.goto_next_sibling() {
2233                    if !cursor.goto_parent() {
2234                        break;
2235                    }
2236                }
2237
2238                while cursor.node().start_byte() == range.start {
2239                    right_node = Some(cursor.node());
2240                    if !cursor.goto_first_child() {
2241                        break;
2242                    }
2243                }
2244
2245                // If there is a candidate node on both sides of the (empty) range, then
2246                // decide between the two by favoring a named node over an anonymous token.
2247                // If both nodes are the same in that regard, favor the right one.
2248                if let Some(right_node) = right_node {
2249                    if right_node.is_named() || !left_node.is_named() {
2250                        layer_result = right_node.byte_range();
2251                    }
2252                }
2253            }
2254
2255            if let Some(previous_result) = &result {
2256                if previous_result.len() < layer_result.len() {
2257                    continue;
2258                }
2259            }
2260            result = Some(layer_result);
2261        }
2262
2263        result
2264    }
2265
2266    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
2267        self.outline_items_containing(0..self.len(), theme)
2268            .map(Outline::new)
2269    }
2270
2271    pub fn symbols_containing<T: ToOffset>(
2272        &self,
2273        position: T,
2274        theme: Option<&SyntaxTheme>,
2275    ) -> Option<Vec<OutlineItem<Anchor>>> {
2276        let position = position.to_offset(self);
2277        let mut items = self.outline_items_containing(
2278            position.saturating_sub(1)..self.len().min(position + 1),
2279            theme,
2280        )?;
2281        let mut prev_depth = None;
2282        items.retain(|item| {
2283            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
2284            prev_depth = Some(item.depth);
2285            result
2286        });
2287        Some(items)
2288    }
2289
2290    fn outline_items_containing(
2291        &self,
2292        range: Range<usize>,
2293        theme: Option<&SyntaxTheme>,
2294    ) -> Option<Vec<OutlineItem<Anchor>>> {
2295        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2296            grammar.outline_config.as_ref().map(|c| &c.query)
2297        });
2298        let configs = matches
2299            .grammars()
2300            .iter()
2301            .map(|g| g.outline_config.as_ref().unwrap())
2302            .collect::<Vec<_>>();
2303
2304        let mut stack = Vec::<Range<usize>>::new();
2305        let mut items = Vec::new();
2306        while let Some(mat) = matches.peek() {
2307            let config = &configs[mat.grammar_index];
2308            let item_node = mat.captures.iter().find_map(|cap| {
2309                if cap.index == config.item_capture_ix {
2310                    Some(cap.node)
2311                } else {
2312                    None
2313                }
2314            })?;
2315
2316            let item_range = item_node.byte_range();
2317            if item_range.end < range.start || item_range.start > range.end {
2318                matches.advance();
2319                continue;
2320            }
2321
2322            let mut buffer_ranges = Vec::new();
2323            for capture in mat.captures {
2324                let node_is_name;
2325                if capture.index == config.name_capture_ix {
2326                    node_is_name = true;
2327                } else if Some(capture.index) == config.context_capture_ix {
2328                    node_is_name = false;
2329                } else {
2330                    continue;
2331                }
2332
2333                let mut range = capture.node.start_byte()..capture.node.end_byte();
2334                let start = capture.node.start_position();
2335                if capture.node.end_position().row > start.row {
2336                    range.end =
2337                        range.start + self.line_len(start.row as u32) as usize - start.column;
2338                }
2339
2340                buffer_ranges.push((range, node_is_name));
2341            }
2342
2343            if buffer_ranges.is_empty() {
2344                continue;
2345            }
2346
2347            let mut text = String::new();
2348            let mut highlight_ranges = Vec::new();
2349            let mut name_ranges = Vec::new();
2350            let mut chunks = self.chunks(
2351                buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
2352                true,
2353            );
2354            for (buffer_range, is_name) in buffer_ranges {
2355                if !text.is_empty() {
2356                    text.push(' ');
2357                }
2358                if is_name {
2359                    let mut start = text.len();
2360                    let end = start + buffer_range.len();
2361
2362                    // When multiple names are captured, then the matcheable text
2363                    // includes the whitespace in between the names.
2364                    if !name_ranges.is_empty() {
2365                        start -= 1;
2366                    }
2367
2368                    name_ranges.push(start..end);
2369                }
2370
2371                let mut offset = buffer_range.start;
2372                chunks.seek(offset);
2373                for mut chunk in chunks.by_ref() {
2374                    if chunk.text.len() > buffer_range.end - offset {
2375                        chunk.text = &chunk.text[0..(buffer_range.end - offset)];
2376                        offset = buffer_range.end;
2377                    } else {
2378                        offset += chunk.text.len();
2379                    }
2380                    let style = chunk
2381                        .syntax_highlight_id
2382                        .zip(theme)
2383                        .and_then(|(highlight, theme)| highlight.style(theme));
2384                    if let Some(style) = style {
2385                        let start = text.len();
2386                        let end = start + chunk.text.len();
2387                        highlight_ranges.push((start..end, style));
2388                    }
2389                    text.push_str(chunk.text);
2390                    if offset >= buffer_range.end {
2391                        break;
2392                    }
2393                }
2394            }
2395
2396            matches.advance();
2397            while stack.last().map_or(false, |prev_range| {
2398                prev_range.start > item_range.start || prev_range.end < item_range.end
2399            }) {
2400                stack.pop();
2401            }
2402            stack.push(item_range.clone());
2403
2404            items.push(OutlineItem {
2405                depth: stack.len() - 1,
2406                range: self.anchor_after(item_range.start)..self.anchor_before(item_range.end),
2407                text,
2408                highlight_ranges,
2409                name_ranges,
2410            })
2411        }
2412        Some(items)
2413    }
2414
2415    /// Returns bracket range pairs overlapping or adjacent to `range`
2416    pub fn bracket_ranges<'a, T: ToOffset>(
2417        &'a self,
2418        range: Range<T>,
2419    ) -> impl Iterator<Item = (Range<usize>, Range<usize>)> + 'a {
2420        // Find bracket pairs that *inclusively* contain the given range.
2421        let range = range.start.to_offset(self).saturating_sub(1)
2422            ..self.len().min(range.end.to_offset(self) + 1);
2423
2424        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2425            grammar.brackets_config.as_ref().map(|c| &c.query)
2426        });
2427        let configs = matches
2428            .grammars()
2429            .iter()
2430            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
2431            .collect::<Vec<_>>();
2432
2433        iter::from_fn(move || {
2434            while let Some(mat) = matches.peek() {
2435                let mut open = None;
2436                let mut close = None;
2437                let config = &configs[mat.grammar_index];
2438                for capture in mat.captures {
2439                    if capture.index == config.open_capture_ix {
2440                        open = Some(capture.node.byte_range());
2441                    } else if capture.index == config.close_capture_ix {
2442                        close = Some(capture.node.byte_range());
2443                    }
2444                }
2445
2446                matches.advance();
2447
2448                let Some((open, close)) = open.zip(close) else { continue };
2449
2450                let bracket_range = open.start..=close.end;
2451                if !bracket_range.overlaps(&range) {
2452                    continue;
2453                }
2454
2455                return Some((open, close));
2456            }
2457            None
2458        })
2459    }
2460
2461    #[allow(clippy::type_complexity)]
2462    pub fn remote_selections_in_range(
2463        &self,
2464        range: Range<Anchor>,
2465    ) -> impl Iterator<
2466        Item = (
2467            ReplicaId,
2468            bool,
2469            CursorShape,
2470            impl Iterator<Item = &Selection<Anchor>> + '_,
2471        ),
2472    > + '_ {
2473        self.remote_selections
2474            .iter()
2475            .filter(|(replica_id, set)| {
2476                **replica_id != self.text.replica_id() && !set.selections.is_empty()
2477            })
2478            .map(move |(replica_id, set)| {
2479                let start_ix = match set.selections.binary_search_by(|probe| {
2480                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
2481                }) {
2482                    Ok(ix) | Err(ix) => ix,
2483                };
2484                let end_ix = match set.selections.binary_search_by(|probe| {
2485                    probe.start.cmp(&range.end, self).then(Ordering::Less)
2486                }) {
2487                    Ok(ix) | Err(ix) => ix,
2488                };
2489
2490                (
2491                    *replica_id,
2492                    set.line_mode,
2493                    set.cursor_shape,
2494                    set.selections[start_ix..end_ix].iter(),
2495                )
2496            })
2497    }
2498
2499    pub fn git_diff_hunks_in_row_range<'a>(
2500        &'a self,
2501        range: Range<u32>,
2502        reversed: bool,
2503    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2504        self.git_diff.hunks_in_row_range(range, self, reversed)
2505    }
2506
2507    pub fn git_diff_hunks_intersecting_range<'a>(
2508        &'a self,
2509        range: Range<Anchor>,
2510        reversed: bool,
2511    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2512        self.git_diff
2513            .hunks_intersecting_range(range, self, reversed)
2514    }
2515
2516    pub fn diagnostics_in_range<'a, T, O>(
2517        &'a self,
2518        search_range: Range<T>,
2519        reversed: bool,
2520    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2521    where
2522        T: 'a + Clone + ToOffset,
2523        O: 'a + FromAnchor + Ord,
2524    {
2525        let mut iterators: Vec<_> = self
2526            .diagnostics
2527            .iter()
2528            .map(|(_, collection)| {
2529                collection
2530                    .range::<T, O>(search_range.clone(), self, true, reversed)
2531                    .peekable()
2532            })
2533            .collect();
2534
2535        std::iter::from_fn(move || {
2536            let (next_ix, _) = iterators
2537                .iter_mut()
2538                .enumerate()
2539                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
2540                .min_by(|(_, a), (_, b)| a.range.start.cmp(&b.range.start))?;
2541            iterators[next_ix].next()
2542        })
2543    }
2544
2545    pub fn diagnostic_groups(
2546        &self,
2547        language_server_id: Option<LanguageServerId>,
2548    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
2549        let mut groups = Vec::new();
2550
2551        if let Some(language_server_id) = language_server_id {
2552            if let Ok(ix) = self
2553                .diagnostics
2554                .binary_search_by_key(&language_server_id, |e| e.0)
2555            {
2556                self.diagnostics[ix]
2557                    .1
2558                    .groups(language_server_id, &mut groups, self);
2559            }
2560        } else {
2561            for (language_server_id, diagnostics) in self.diagnostics.iter() {
2562                diagnostics.groups(*language_server_id, &mut groups, self);
2563            }
2564        }
2565
2566        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
2567            let a_start = &group_a.entries[group_a.primary_ix].range.start;
2568            let b_start = &group_b.entries[group_b.primary_ix].range.start;
2569            a_start.cmp(b_start, self).then_with(|| id_a.cmp(&id_b))
2570        });
2571
2572        groups
2573    }
2574
2575    pub fn diagnostic_group<'a, O>(
2576        &'a self,
2577        group_id: usize,
2578    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2579    where
2580        O: 'a + FromAnchor,
2581    {
2582        self.diagnostics
2583            .iter()
2584            .flat_map(move |(_, set)| set.group(group_id, self))
2585    }
2586
2587    pub fn diagnostics_update_count(&self) -> usize {
2588        self.diagnostics_update_count
2589    }
2590
2591    pub fn parse_count(&self) -> usize {
2592        self.parse_count
2593    }
2594
2595    pub fn selections_update_count(&self) -> usize {
2596        self.selections_update_count
2597    }
2598
2599    pub fn file(&self) -> Option<&Arc<dyn File>> {
2600        self.file.as_ref()
2601    }
2602
2603    pub fn resolve_file_path(&self, cx: &AppContext, include_root: bool) -> Option<PathBuf> {
2604        if let Some(file) = self.file() {
2605            if file.path().file_name().is_none() || include_root {
2606                Some(file.full_path(cx))
2607            } else {
2608                Some(file.path().to_path_buf())
2609            }
2610        } else {
2611            None
2612        }
2613    }
2614
2615    pub fn file_update_count(&self) -> usize {
2616        self.file_update_count
2617    }
2618
2619    pub fn git_diff_update_count(&self) -> usize {
2620        self.git_diff_update_count
2621    }
2622}
2623
2624fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
2625    indent_size_for_text(text.chars_at(Point::new(row, 0)))
2626}
2627
2628pub fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
2629    let mut result = IndentSize::spaces(0);
2630    for c in text {
2631        let kind = match c {
2632            ' ' => IndentKind::Space,
2633            '\t' => IndentKind::Tab,
2634            _ => break,
2635        };
2636        if result.len == 0 {
2637            result.kind = kind;
2638        }
2639        result.len += 1;
2640    }
2641    result
2642}
2643
2644impl Clone for BufferSnapshot {
2645    fn clone(&self) -> Self {
2646        Self {
2647            text: self.text.clone(),
2648            git_diff: self.git_diff.clone(),
2649            syntax: self.syntax.clone(),
2650            file: self.file.clone(),
2651            remote_selections: self.remote_selections.clone(),
2652            diagnostics: self.diagnostics.clone(),
2653            selections_update_count: self.selections_update_count,
2654            diagnostics_update_count: self.diagnostics_update_count,
2655            file_update_count: self.file_update_count,
2656            git_diff_update_count: self.git_diff_update_count,
2657            language: self.language.clone(),
2658            parse_count: self.parse_count,
2659        }
2660    }
2661}
2662
2663impl Deref for BufferSnapshot {
2664    type Target = text::BufferSnapshot;
2665
2666    fn deref(&self) -> &Self::Target {
2667        &self.text
2668    }
2669}
2670
2671unsafe impl<'a> Send for BufferChunks<'a> {}
2672
2673impl<'a> BufferChunks<'a> {
2674    pub(crate) fn new(
2675        text: &'a Rope,
2676        range: Range<usize>,
2677        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
2678        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
2679    ) -> Self {
2680        let mut highlights = None;
2681        if let Some((captures, highlight_maps)) = syntax {
2682            highlights = Some(BufferChunkHighlights {
2683                captures,
2684                next_capture: None,
2685                stack: Default::default(),
2686                highlight_maps,
2687            })
2688        }
2689
2690        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2691        let chunks = text.chunks_in_range(range.clone());
2692
2693        BufferChunks {
2694            range,
2695            chunks,
2696            diagnostic_endpoints,
2697            error_depth: 0,
2698            warning_depth: 0,
2699            information_depth: 0,
2700            hint_depth: 0,
2701            unnecessary_depth: 0,
2702            highlights,
2703        }
2704    }
2705
2706    pub fn seek(&mut self, offset: usize) {
2707        self.range.start = offset;
2708        self.chunks.seek(self.range.start);
2709        if let Some(highlights) = self.highlights.as_mut() {
2710            highlights
2711                .stack
2712                .retain(|(end_offset, _)| *end_offset > offset);
2713            if let Some(capture) = &highlights.next_capture {
2714                if offset >= capture.node.start_byte() {
2715                    let next_capture_end = capture.node.end_byte();
2716                    if offset < next_capture_end {
2717                        highlights.stack.push((
2718                            next_capture_end,
2719                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
2720                        ));
2721                    }
2722                    highlights.next_capture.take();
2723                }
2724            }
2725            highlights.captures.set_byte_range(self.range.clone());
2726        }
2727    }
2728
2729    pub fn offset(&self) -> usize {
2730        self.range.start
2731    }
2732
2733    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2734        let depth = match endpoint.severity {
2735            DiagnosticSeverity::ERROR => &mut self.error_depth,
2736            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2737            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2738            DiagnosticSeverity::HINT => &mut self.hint_depth,
2739            _ => return,
2740        };
2741        if endpoint.is_start {
2742            *depth += 1;
2743        } else {
2744            *depth -= 1;
2745        }
2746
2747        if endpoint.is_unnecessary {
2748            if endpoint.is_start {
2749                self.unnecessary_depth += 1;
2750            } else {
2751                self.unnecessary_depth -= 1;
2752            }
2753        }
2754    }
2755
2756    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2757        if self.error_depth > 0 {
2758            Some(DiagnosticSeverity::ERROR)
2759        } else if self.warning_depth > 0 {
2760            Some(DiagnosticSeverity::WARNING)
2761        } else if self.information_depth > 0 {
2762            Some(DiagnosticSeverity::INFORMATION)
2763        } else if self.hint_depth > 0 {
2764            Some(DiagnosticSeverity::HINT)
2765        } else {
2766            None
2767        }
2768    }
2769
2770    fn current_code_is_unnecessary(&self) -> bool {
2771        self.unnecessary_depth > 0
2772    }
2773}
2774
2775impl<'a> Iterator for BufferChunks<'a> {
2776    type Item = Chunk<'a>;
2777
2778    fn next(&mut self) -> Option<Self::Item> {
2779        let mut next_capture_start = usize::MAX;
2780        let mut next_diagnostic_endpoint = usize::MAX;
2781
2782        if let Some(highlights) = self.highlights.as_mut() {
2783            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2784                if *parent_capture_end <= self.range.start {
2785                    highlights.stack.pop();
2786                } else {
2787                    break;
2788                }
2789            }
2790
2791            if highlights.next_capture.is_none() {
2792                highlights.next_capture = highlights.captures.next();
2793            }
2794
2795            while let Some(capture) = highlights.next_capture.as_ref() {
2796                if self.range.start < capture.node.start_byte() {
2797                    next_capture_start = capture.node.start_byte();
2798                    break;
2799                } else {
2800                    let highlight_id =
2801                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
2802                    highlights
2803                        .stack
2804                        .push((capture.node.end_byte(), highlight_id));
2805                    highlights.next_capture = highlights.captures.next();
2806                }
2807            }
2808        }
2809
2810        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2811            if endpoint.offset <= self.range.start {
2812                self.update_diagnostic_depths(endpoint);
2813                self.diagnostic_endpoints.next();
2814            } else {
2815                next_diagnostic_endpoint = endpoint.offset;
2816                break;
2817            }
2818        }
2819
2820        if let Some(chunk) = self.chunks.peek() {
2821            let chunk_start = self.range.start;
2822            let mut chunk_end = (self.chunks.offset() + chunk.len())
2823                .min(next_capture_start)
2824                .min(next_diagnostic_endpoint);
2825            let mut highlight_id = None;
2826            if let Some(highlights) = self.highlights.as_ref() {
2827                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2828                    chunk_end = chunk_end.min(*parent_capture_end);
2829                    highlight_id = Some(*parent_highlight_id);
2830                }
2831            }
2832
2833            let slice =
2834                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2835            self.range.start = chunk_end;
2836            if self.range.start == self.chunks.offset() + chunk.len() {
2837                self.chunks.next().unwrap();
2838            }
2839
2840            Some(Chunk {
2841                text: slice,
2842                syntax_highlight_id: highlight_id,
2843                highlight_style: None,
2844                diagnostic_severity: self.current_diagnostic_severity(),
2845                is_unnecessary: self.current_code_is_unnecessary(),
2846            })
2847        } else {
2848            None
2849        }
2850    }
2851}
2852
2853impl operation_queue::Operation for Operation {
2854    fn lamport_timestamp(&self) -> clock::Lamport {
2855        match self {
2856            Operation::Buffer(_) => {
2857                unreachable!("buffer operations should never be deferred at this layer")
2858            }
2859            Operation::UpdateDiagnostics {
2860                lamport_timestamp, ..
2861            }
2862            | Operation::UpdateSelections {
2863                lamport_timestamp, ..
2864            }
2865            | Operation::UpdateCompletionTriggers {
2866                lamport_timestamp, ..
2867            } => *lamport_timestamp,
2868        }
2869    }
2870}
2871
2872impl Default for Diagnostic {
2873    fn default() -> Self {
2874        Self {
2875            source: Default::default(),
2876            code: None,
2877            severity: DiagnosticSeverity::ERROR,
2878            message: Default::default(),
2879            group_id: 0,
2880            is_primary: false,
2881            is_valid: true,
2882            is_disk_based: false,
2883            is_unnecessary: false,
2884        }
2885    }
2886}
2887
2888impl IndentSize {
2889    pub fn spaces(len: u32) -> Self {
2890        Self {
2891            len,
2892            kind: IndentKind::Space,
2893        }
2894    }
2895
2896    pub fn tab() -> Self {
2897        Self {
2898            len: 1,
2899            kind: IndentKind::Tab,
2900        }
2901    }
2902
2903    pub fn chars(&self) -> impl Iterator<Item = char> {
2904        iter::repeat(self.char()).take(self.len as usize)
2905    }
2906
2907    pub fn char(&self) -> char {
2908        match self.kind {
2909            IndentKind::Space => ' ',
2910            IndentKind::Tab => '\t',
2911        }
2912    }
2913
2914    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
2915        match direction {
2916            Ordering::Less => {
2917                if self.kind == size.kind && self.len >= size.len {
2918                    self.len -= size.len;
2919                }
2920            }
2921            Ordering::Equal => {}
2922            Ordering::Greater => {
2923                if self.len == 0 {
2924                    self = size;
2925                } else if self.kind == size.kind {
2926                    self.len += size.len;
2927                }
2928            }
2929        }
2930        self
2931    }
2932}
2933
2934impl Completion {
2935    pub fn sort_key(&self) -> (usize, &str) {
2936        let kind_key = match self.lsp_completion.kind {
2937            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2938            _ => 1,
2939        };
2940        (kind_key, &self.label.text[self.label.filter_range.clone()])
2941    }
2942
2943    pub fn is_snippet(&self) -> bool {
2944        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2945    }
2946}
2947
2948pub fn contiguous_ranges(
2949    values: impl Iterator<Item = u32>,
2950    max_len: usize,
2951) -> impl Iterator<Item = Range<u32>> {
2952    let mut values = values;
2953    let mut current_range: Option<Range<u32>> = None;
2954    std::iter::from_fn(move || loop {
2955        if let Some(value) = values.next() {
2956            if let Some(range) = &mut current_range {
2957                if value == range.end && range.len() < max_len {
2958                    range.end += 1;
2959                    continue;
2960                }
2961            }
2962
2963            let prev_range = current_range.clone();
2964            current_range = Some(value..(value + 1));
2965            if prev_range.is_some() {
2966                return prev_range;
2967            }
2968        } else {
2969            return current_range.take();
2970        }
2971    })
2972}
2973
2974pub fn char_kind(c: char) -> CharKind {
2975    if c.is_whitespace() {
2976        CharKind::Whitespace
2977    } else if c.is_alphanumeric() || c == '_' {
2978        CharKind::Word
2979    } else {
2980        CharKind::Punctuation
2981    }
2982}
2983
2984/// Find all of the ranges of whitespace that occur at the ends of lines
2985/// in the given rope.
2986///
2987/// This could also be done with a regex search, but this implementation
2988/// avoids copying text.
2989pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
2990    let mut ranges = Vec::new();
2991
2992    let mut offset = 0;
2993    let mut prev_chunk_trailing_whitespace_range = 0..0;
2994    for chunk in rope.chunks() {
2995        let mut prev_line_trailing_whitespace_range = 0..0;
2996        for (i, line) in chunk.split('\n').enumerate() {
2997            let line_end_offset = offset + line.len();
2998            let trimmed_line_len = line.trim_end_matches(|c| matches!(c, ' ' | '\t')).len();
2999            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
3000
3001            if i == 0 && trimmed_line_len == 0 {
3002                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
3003            }
3004            if !prev_line_trailing_whitespace_range.is_empty() {
3005                ranges.push(prev_line_trailing_whitespace_range);
3006            }
3007
3008            offset = line_end_offset + 1;
3009            prev_line_trailing_whitespace_range = trailing_whitespace_range;
3010        }
3011
3012        offset -= 1;
3013        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
3014    }
3015
3016    if !prev_chunk_trailing_whitespace_range.is_empty() {
3017        ranges.push(prev_chunk_trailing_whitespace_range);
3018    }
3019
3020    ranges
3021}