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    language_settings::{language_settings, LanguageSettings},
   9    outline::OutlineItem,
  10    syntax_map::{
  11        SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxSnapshot, ToTreeSitterPoint,
  12    },
  13    CodeLabel, LanguageScope, Outline,
  14};
  15use anyhow::{anyhow, Result};
  16use clock::ReplicaId;
  17use fs::LineEnding;
  18use futures::FutureExt as _;
  19use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, Task};
  20use lsp::LanguageServerId;
  21use parking_lot::Mutex;
  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    pub is_tab: bool,
 315}
 316
 317pub struct Diff {
 318    pub(crate) base_version: clock::Global,
 319    line_ending: LineEnding,
 320    edits: Vec<(Range<usize>, Arc<str>)>,
 321}
 322
 323#[derive(Clone, Copy)]
 324pub(crate) struct DiagnosticEndpoint {
 325    offset: usize,
 326    is_start: bool,
 327    severity: DiagnosticSeverity,
 328    is_unnecessary: bool,
 329}
 330
 331#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 332pub enum CharKind {
 333    Punctuation,
 334    Whitespace,
 335    Word,
 336}
 337
 338impl CharKind {
 339    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 340        if treat_punctuation_as_word && self == CharKind::Punctuation {
 341            CharKind::Word
 342        } else {
 343            self
 344        }
 345    }
 346}
 347
 348impl Buffer {
 349    pub fn new<T: Into<String>>(
 350        replica_id: ReplicaId,
 351        base_text: T,
 352        cx: &mut ModelContext<Self>,
 353    ) -> Self {
 354        Self::build(
 355            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 356            None,
 357            None,
 358        )
 359    }
 360
 361    pub fn from_proto(
 362        replica_id: ReplicaId,
 363        message: proto::BufferState,
 364        file: Option<Arc<dyn File>>,
 365    ) -> Result<Self> {
 366        let buffer = TextBuffer::new(replica_id, message.id, message.base_text);
 367        let mut this = Self::build(
 368            buffer,
 369            message.diff_base.map(|text| text.into_boxed_str().into()),
 370            file,
 371        );
 372        this.text.set_line_ending(proto::deserialize_line_ending(
 373            rpc::proto::LineEnding::from_i32(message.line_ending)
 374                .ok_or_else(|| anyhow!("missing line_ending"))?,
 375        ));
 376        this.saved_version = proto::deserialize_version(&message.saved_version);
 377        this.saved_version_fingerprint =
 378            proto::deserialize_fingerprint(&message.saved_version_fingerprint)?;
 379        this.saved_mtime = message
 380            .saved_mtime
 381            .ok_or_else(|| anyhow!("invalid saved_mtime"))?
 382            .into();
 383        Ok(this)
 384    }
 385
 386    pub fn to_proto(&self) -> proto::BufferState {
 387        proto::BufferState {
 388            id: self.remote_id(),
 389            file: self.file.as_ref().map(|f| f.to_proto()),
 390            base_text: self.base_text().to_string(),
 391            diff_base: self.diff_base.as_ref().map(|h| h.to_string()),
 392            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 393            saved_version: proto::serialize_version(&self.saved_version),
 394            saved_version_fingerprint: proto::serialize_fingerprint(self.saved_version_fingerprint),
 395            saved_mtime: Some(self.saved_mtime.into()),
 396        }
 397    }
 398
 399    pub fn serialize_ops(
 400        &self,
 401        since: Option<clock::Global>,
 402        cx: &AppContext,
 403    ) -> Task<Vec<proto::Operation>> {
 404        let mut operations = Vec::new();
 405        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 406
 407        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 408            proto::serialize_operation(&Operation::UpdateSelections {
 409                selections: set.selections.clone(),
 410                lamport_timestamp: set.lamport_timestamp,
 411                line_mode: set.line_mode,
 412                cursor_shape: set.cursor_shape,
 413            })
 414        }));
 415
 416        for (server_id, diagnostics) in &self.diagnostics {
 417            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 418                lamport_timestamp: self.diagnostics_timestamp,
 419                server_id: *server_id,
 420                diagnostics: diagnostics.iter().cloned().collect(),
 421            }));
 422        }
 423
 424        operations.push(proto::serialize_operation(
 425            &Operation::UpdateCompletionTriggers {
 426                triggers: self.completion_triggers.clone(),
 427                lamport_timestamp: self.completion_triggers_timestamp,
 428            },
 429        ));
 430
 431        let text_operations = self.text.operations().clone();
 432        cx.background().spawn(async move {
 433            let since = since.unwrap_or_default();
 434            operations.extend(
 435                text_operations
 436                    .iter()
 437                    .filter(|(_, op)| !since.observed(op.local_timestamp()))
 438                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 439            );
 440            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 441            operations
 442        })
 443    }
 444
 445    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 446        self.set_language(Some(language), cx);
 447        self
 448    }
 449
 450    pub fn build(
 451        buffer: TextBuffer,
 452        diff_base: Option<String>,
 453        file: Option<Arc<dyn File>>,
 454    ) -> Self {
 455        let saved_mtime = if let Some(file) = file.as_ref() {
 456            file.mtime()
 457        } else {
 458            UNIX_EPOCH
 459        };
 460
 461        Self {
 462            saved_mtime,
 463            saved_version: buffer.version(),
 464            saved_version_fingerprint: buffer.as_rope().fingerprint(),
 465            transaction_depth: 0,
 466            was_dirty_before_starting_transaction: None,
 467            text: buffer,
 468            diff_base,
 469            git_diff_status: GitDiffStatus {
 470                diff: git::diff::BufferDiff::new(),
 471                update_in_progress: false,
 472                update_requested: false,
 473            },
 474            file,
 475            syntax_map: Mutex::new(SyntaxMap::new()),
 476            parsing_in_background: false,
 477            parse_count: 0,
 478            sync_parse_timeout: Duration::from_millis(1),
 479            autoindent_requests: Default::default(),
 480            pending_autoindent: Default::default(),
 481            language: None,
 482            remote_selections: Default::default(),
 483            selections_update_count: 0,
 484            diagnostics: Default::default(),
 485            diagnostics_update_count: 0,
 486            diagnostics_timestamp: Default::default(),
 487            file_update_count: 0,
 488            git_diff_update_count: 0,
 489            completion_triggers: Default::default(),
 490            completion_triggers_timestamp: Default::default(),
 491            deferred_ops: OperationQueue::new(),
 492        }
 493    }
 494
 495    pub fn snapshot(&self) -> BufferSnapshot {
 496        let text = self.text.snapshot();
 497        let mut syntax_map = self.syntax_map.lock();
 498        syntax_map.interpolate(&text);
 499        let syntax = syntax_map.snapshot();
 500
 501        BufferSnapshot {
 502            text,
 503            syntax,
 504            git_diff: self.git_diff_status.diff.clone(),
 505            file: self.file.clone(),
 506            remote_selections: self.remote_selections.clone(),
 507            diagnostics: self.diagnostics.clone(),
 508            diagnostics_update_count: self.diagnostics_update_count,
 509            file_update_count: self.file_update_count,
 510            git_diff_update_count: self.git_diff_update_count,
 511            language: self.language.clone(),
 512            parse_count: self.parse_count,
 513            selections_update_count: self.selections_update_count,
 514        }
 515    }
 516
 517    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 518        &self.text
 519    }
 520
 521    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 522        self.text.snapshot()
 523    }
 524
 525    pub fn file(&self) -> Option<&Arc<dyn File>> {
 526        self.file.as_ref()
 527    }
 528
 529    pub fn saved_version(&self) -> &clock::Global {
 530        &self.saved_version
 531    }
 532
 533    pub fn saved_version_fingerprint(&self) -> RopeFingerprint {
 534        self.saved_version_fingerprint
 535    }
 536
 537    pub fn saved_mtime(&self) -> SystemTime {
 538        self.saved_mtime
 539    }
 540
 541    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 542        self.syntax_map.lock().clear();
 543        self.language = language;
 544        self.reparse(cx);
 545        cx.emit(Event::LanguageChanged);
 546    }
 547
 548    pub fn set_language_registry(&mut self, language_registry: Arc<LanguageRegistry>) {
 549        self.syntax_map
 550            .lock()
 551            .set_language_registry(language_registry);
 552    }
 553
 554    pub fn did_save(
 555        &mut self,
 556        version: clock::Global,
 557        fingerprint: RopeFingerprint,
 558        mtime: SystemTime,
 559        cx: &mut ModelContext<Self>,
 560    ) {
 561        self.saved_version = version;
 562        self.saved_version_fingerprint = fingerprint;
 563        self.saved_mtime = mtime;
 564        cx.emit(Event::Saved);
 565        cx.notify();
 566    }
 567
 568    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 569        cx.spawn(|this, mut cx| async move {
 570            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 571                let file = this.file.as_ref()?.as_local()?;
 572                Some((file.mtime(), file.load(cx)))
 573            }) {
 574                let new_text = new_text.await?;
 575                let diff = this
 576                    .read_with(&cx, |this, cx| this.diff(new_text, cx))
 577                    .await;
 578                this.update(&mut cx, |this, cx| {
 579                    if this.version() == diff.base_version {
 580                        this.finalize_last_transaction();
 581                        this.apply_diff(diff, cx);
 582                        if let Some(transaction) = this.finalize_last_transaction().cloned() {
 583                            this.did_reload(
 584                                this.version(),
 585                                this.as_rope().fingerprint(),
 586                                this.line_ending(),
 587                                new_mtime,
 588                                cx,
 589                            );
 590                            return Ok(Some(transaction));
 591                        }
 592                    }
 593                    Ok(None)
 594                })
 595            } else {
 596                Ok(None)
 597            }
 598        })
 599    }
 600
 601    pub fn did_reload(
 602        &mut self,
 603        version: clock::Global,
 604        fingerprint: RopeFingerprint,
 605        line_ending: LineEnding,
 606        mtime: SystemTime,
 607        cx: &mut ModelContext<Self>,
 608    ) {
 609        self.saved_version = version;
 610        self.saved_version_fingerprint = fingerprint;
 611        self.text.set_line_ending(line_ending);
 612        self.saved_mtime = mtime;
 613        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 614            file.buffer_reloaded(
 615                self.remote_id(),
 616                &self.saved_version,
 617                self.saved_version_fingerprint,
 618                self.line_ending(),
 619                self.saved_mtime,
 620                cx,
 621            );
 622        }
 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_2(&mut self, cx: &mut ModelContext<Self>) -> Option<Task<()>> {
 685        let diff_base = self.diff_base.clone()?; // TODO: Make this an Arc
 686        let snapshot = self.snapshot();
 687
 688        let mut diff = self.git_diff_status.diff.clone();
 689        let diff = cx.background().spawn(async move {
 690            diff.update(&diff_base, &snapshot).await;
 691            diff
 692        });
 693
 694        let handle = cx.weak_handle();
 695        Some(cx.spawn_weak(|_, mut cx| async move {
 696            let buffer_diff = diff.await;
 697            if let Some(this) = handle.upgrade(&mut cx) {
 698                this.update(&mut cx, |this, _| {
 699                    this.git_diff_status.diff = buffer_diff;
 700                    this.git_diff_update_count += 1;
 701                })
 702            }
 703        }))
 704    }
 705
 706    fn git_diff_recalc(&mut self, cx: &mut ModelContext<Self>) {
 707        if self.git_diff_status.update_in_progress {
 708            self.git_diff_status.update_requested = true;
 709            return;
 710        }
 711
 712        if let Some(diff_base) = &self.diff_base {
 713            self.git_diff_status.update_in_progress = true;
 714            let snapshot = self.snapshot();
 715            let diff_base = diff_base.clone();
 716
 717            let mut diff = self.git_diff_status.diff.clone();
 718            let diff = cx.background().spawn(async move {
 719                diff.update(&diff_base, &snapshot).await;
 720                diff
 721            });
 722
 723            cx.spawn_weak(|this, mut cx| async move {
 724                let buffer_diff = diff.await;
 725                if let Some(this) = this.upgrade(&cx) {
 726                    this.update(&mut cx, |this, cx| {
 727                        this.git_diff_status.diff = buffer_diff;
 728                        this.git_diff_update_count += 1;
 729                        cx.notify();
 730
 731                        if this.git_diff_status.update_requested {
 732                            this.git_diff_recalc(cx);
 733                        } else {
 734                            this.git_diff_status.update_in_progress = false;
 735                        }
 736                    })
 737                }
 738            })
 739            .detach()
 740        } else {
 741            let snapshot = self.snapshot();
 742            self.git_diff_status.diff.clear(&snapshot);
 743            self.git_diff_update_count += 1;
 744            cx.notify();
 745        }
 746    }
 747
 748    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 749        cx.emit(Event::Closed);
 750    }
 751
 752    pub fn language(&self) -> Option<&Arc<Language>> {
 753        self.language.as_ref()
 754    }
 755
 756    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
 757        let offset = position.to_offset(self);
 758        self.syntax_map
 759            .lock()
 760            .layers_for_range(offset..offset, &self.text)
 761            .last()
 762            .map(|info| info.language.clone())
 763            .or_else(|| self.language.clone())
 764    }
 765
 766    pub fn parse_count(&self) -> usize {
 767        self.parse_count
 768    }
 769
 770    pub fn selections_update_count(&self) -> usize {
 771        self.selections_update_count
 772    }
 773
 774    pub fn diagnostics_update_count(&self) -> usize {
 775        self.diagnostics_update_count
 776    }
 777
 778    pub fn file_update_count(&self) -> usize {
 779        self.file_update_count
 780    }
 781
 782    pub fn git_diff_update_count(&self) -> usize {
 783        self.git_diff_update_count
 784    }
 785
 786    #[cfg(any(test, feature = "test-support"))]
 787    pub fn is_parsing(&self) -> bool {
 788        self.parsing_in_background
 789    }
 790
 791    pub fn contains_unknown_injections(&self) -> bool {
 792        self.syntax_map.lock().contains_unknown_injections()
 793    }
 794
 795    #[cfg(test)]
 796    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 797        self.sync_parse_timeout = timeout;
 798    }
 799
 800    /// Called after an edit to synchronize the buffer's main parse tree with
 801    /// the buffer's new underlying state.
 802    ///
 803    /// Locks the syntax map and interpolates the edits since the last reparse
 804    /// into the foreground syntax tree.
 805    ///
 806    /// Then takes a stable snapshot of the syntax map before unlocking it.
 807    /// The snapshot with the interpolated edits is sent to a background thread,
 808    /// where we ask Tree-sitter to perform an incremental parse.
 809    ///
 810    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
 811    /// waiting on the parse to complete. As soon as it completes, we proceed
 812    /// synchronously, unless a 1ms timeout elapses.
 813    ///
 814    /// If we time out waiting on the parse, we spawn a second task waiting
 815    /// until the parse does complete and return with the interpolated tree still
 816    /// in the foreground. When the background parse completes, call back into
 817    /// the main thread and assign the foreground parse state.
 818    ///
 819    /// If the buffer or grammar changed since the start of the background parse,
 820    /// initiate an additional reparse recursively. To avoid concurrent parses
 821    /// for the same buffer, we only initiate a new parse if we are not already
 822    /// parsing in the background.
 823    pub fn reparse(&mut self, cx: &mut ModelContext<Self>) {
 824        if self.parsing_in_background {
 825            return;
 826        }
 827        let language = if let Some(language) = self.language.clone() {
 828            language
 829        } else {
 830            return;
 831        };
 832
 833        let text = self.text_snapshot();
 834        let parsed_version = self.version();
 835
 836        let mut syntax_map = self.syntax_map.lock();
 837        syntax_map.interpolate(&text);
 838        let language_registry = syntax_map.language_registry();
 839        let mut syntax_snapshot = syntax_map.snapshot();
 840        drop(syntax_map);
 841
 842        let parse_task = cx.background().spawn({
 843            let language = language.clone();
 844            let language_registry = language_registry.clone();
 845            async move {
 846                syntax_snapshot.reparse(&text, language_registry, language);
 847                syntax_snapshot
 848            }
 849        });
 850
 851        match cx
 852            .background()
 853            .block_with_timeout(self.sync_parse_timeout, parse_task)
 854        {
 855            Ok(new_syntax_snapshot) => {
 856                self.did_finish_parsing(new_syntax_snapshot, cx);
 857                return;
 858            }
 859            Err(parse_task) => {
 860                self.parsing_in_background = true;
 861                cx.spawn(move |this, mut cx| async move {
 862                    let new_syntax_map = parse_task.await;
 863                    this.update(&mut cx, move |this, cx| {
 864                        let grammar_changed =
 865                            this.language.as_ref().map_or(true, |current_language| {
 866                                !Arc::ptr_eq(&language, current_language)
 867                            });
 868                        let language_registry_changed = new_syntax_map
 869                            .contains_unknown_injections()
 870                            && language_registry.map_or(false, |registry| {
 871                                registry.version() != new_syntax_map.language_registry_version()
 872                            });
 873                        let parse_again = language_registry_changed
 874                            || grammar_changed
 875                            || this.version.changed_since(&parsed_version);
 876                        this.did_finish_parsing(new_syntax_map, cx);
 877                        this.parsing_in_background = false;
 878                        if parse_again {
 879                            this.reparse(cx);
 880                        }
 881                    });
 882                })
 883                .detach();
 884            }
 885        }
 886    }
 887
 888    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut ModelContext<Self>) {
 889        self.parse_count += 1;
 890        self.syntax_map.lock().did_parse(syntax_snapshot);
 891        self.request_autoindent(cx);
 892        cx.emit(Event::Reparsed);
 893        cx.notify();
 894    }
 895
 896    pub fn update_diagnostics(
 897        &mut self,
 898        server_id: LanguageServerId,
 899        diagnostics: DiagnosticSet,
 900        cx: &mut ModelContext<Self>,
 901    ) {
 902        let lamport_timestamp = self.text.lamport_clock.tick();
 903        let op = Operation::UpdateDiagnostics {
 904            server_id,
 905            diagnostics: diagnostics.iter().cloned().collect(),
 906            lamport_timestamp,
 907        };
 908        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
 909        self.send_operation(op, cx);
 910    }
 911
 912    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 913        if let Some(indent_sizes) = self.compute_autoindents() {
 914            let indent_sizes = cx.background().spawn(indent_sizes);
 915            match cx
 916                .background()
 917                .block_with_timeout(Duration::from_micros(500), indent_sizes)
 918            {
 919                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
 920                Err(indent_sizes) => {
 921                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 922                        let indent_sizes = indent_sizes.await;
 923                        this.update(&mut cx, |this, cx| {
 924                            this.apply_autoindents(indent_sizes, cx);
 925                        });
 926                    }));
 927                }
 928            }
 929        } else {
 930            self.autoindent_requests.clear();
 931        }
 932    }
 933
 934    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
 935        let max_rows_between_yields = 100;
 936        let snapshot = self.snapshot();
 937        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
 938            return None;
 939        }
 940
 941        let autoindent_requests = self.autoindent_requests.clone();
 942        Some(async move {
 943            let mut indent_sizes = BTreeMap::new();
 944            for request in autoindent_requests {
 945                // Resolve each edited range to its row in the current buffer and in the
 946                // buffer before this batch of edits.
 947                let mut row_ranges = Vec::new();
 948                let mut old_to_new_rows = BTreeMap::new();
 949                let mut language_indent_sizes_by_new_row = Vec::new();
 950                for entry in &request.entries {
 951                    let position = entry.range.start;
 952                    let new_row = position.to_point(&snapshot).row;
 953                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
 954                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
 955
 956                    if !entry.first_line_is_new {
 957                        let old_row = position.to_point(&request.before_edit).row;
 958                        old_to_new_rows.insert(old_row, new_row);
 959                    }
 960                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
 961                }
 962
 963                // Build a map containing the suggested indentation for each of the edited lines
 964                // with respect to the state of the buffer before these edits. This map is keyed
 965                // by the rows for these lines in the current state of the buffer.
 966                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
 967                let old_edited_ranges =
 968                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 969                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 970                let mut language_indent_size = IndentSize::default();
 971                for old_edited_range in old_edited_ranges {
 972                    let suggestions = request
 973                        .before_edit
 974                        .suggest_autoindents(old_edited_range.clone())
 975                        .into_iter()
 976                        .flatten();
 977                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 978                        if let Some(suggestion) = suggestion {
 979                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
 980
 981                            // Find the indent size based on the language for this row.
 982                            while let Some((row, size)) = language_indent_sizes.peek() {
 983                                if *row > new_row {
 984                                    break;
 985                                }
 986                                language_indent_size = *size;
 987                                language_indent_sizes.next();
 988                            }
 989
 990                            let suggested_indent = old_to_new_rows
 991                                .get(&suggestion.basis_row)
 992                                .and_then(|from_row| {
 993                                    Some(old_suggestions.get(from_row).copied()?.0)
 994                                })
 995                                .unwrap_or_else(|| {
 996                                    request
 997                                        .before_edit
 998                                        .indent_size_for_line(suggestion.basis_row)
 999                                })
1000                                .with_delta(suggestion.delta, language_indent_size);
1001                            old_suggestions
1002                                .insert(new_row, (suggested_indent, suggestion.within_error));
1003                        }
1004                    }
1005                    yield_now().await;
1006                }
1007
1008                // In block mode, only compute indentation suggestions for the first line
1009                // of each insertion. Otherwise, compute suggestions for every inserted line.
1010                let new_edited_row_ranges = contiguous_ranges(
1011                    row_ranges.iter().flat_map(|(range, _)| {
1012                        if request.is_block_mode {
1013                            range.start..range.start + 1
1014                        } else {
1015                            range.clone()
1016                        }
1017                    }),
1018                    max_rows_between_yields,
1019                );
1020
1021                // Compute new suggestions for each line, but only include them in the result
1022                // if they differ from the old suggestion for that line.
1023                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1024                let mut language_indent_size = IndentSize::default();
1025                for new_edited_row_range in new_edited_row_ranges {
1026                    let suggestions = snapshot
1027                        .suggest_autoindents(new_edited_row_range.clone())
1028                        .into_iter()
1029                        .flatten();
1030                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1031                        if let Some(suggestion) = suggestion {
1032                            // Find the indent size based on the language for this row.
1033                            while let Some((row, size)) = language_indent_sizes.peek() {
1034                                if *row > new_row {
1035                                    break;
1036                                }
1037                                language_indent_size = *size;
1038                                language_indent_sizes.next();
1039                            }
1040
1041                            let suggested_indent = indent_sizes
1042                                .get(&suggestion.basis_row)
1043                                .copied()
1044                                .unwrap_or_else(|| {
1045                                    snapshot.indent_size_for_line(suggestion.basis_row)
1046                                })
1047                                .with_delta(suggestion.delta, language_indent_size);
1048                            if old_suggestions.get(&new_row).map_or(
1049                                true,
1050                                |(old_indentation, was_within_error)| {
1051                                    suggested_indent != *old_indentation
1052                                        && (!suggestion.within_error || *was_within_error)
1053                                },
1054                            ) {
1055                                indent_sizes.insert(new_row, suggested_indent);
1056                            }
1057                        }
1058                    }
1059                    yield_now().await;
1060                }
1061
1062                // For each block of inserted text, adjust the indentation of the remaining
1063                // lines of the block by the same amount as the first line was adjusted.
1064                if request.is_block_mode {
1065                    for (row_range, original_indent_column) in
1066                        row_ranges
1067                            .into_iter()
1068                            .filter_map(|(range, original_indent_column)| {
1069                                if range.len() > 1 {
1070                                    Some((range, original_indent_column?))
1071                                } else {
1072                                    None
1073                                }
1074                            })
1075                    {
1076                        let new_indent = indent_sizes
1077                            .get(&row_range.start)
1078                            .copied()
1079                            .unwrap_or_else(|| snapshot.indent_size_for_line(row_range.start));
1080                        let delta = new_indent.len as i64 - original_indent_column as i64;
1081                        if delta != 0 {
1082                            for row in row_range.skip(1) {
1083                                indent_sizes.entry(row).or_insert_with(|| {
1084                                    let mut size = snapshot.indent_size_for_line(row);
1085                                    if size.kind == new_indent.kind {
1086                                        match delta.cmp(&0) {
1087                                            Ordering::Greater => size.len += delta as u32,
1088                                            Ordering::Less => {
1089                                                size.len = size.len.saturating_sub(-delta as u32)
1090                                            }
1091                                            Ordering::Equal => {}
1092                                        }
1093                                    }
1094                                    size
1095                                });
1096                            }
1097                        }
1098                    }
1099                }
1100            }
1101
1102            indent_sizes
1103        })
1104    }
1105
1106    fn apply_autoindents(
1107        &mut self,
1108        indent_sizes: BTreeMap<u32, IndentSize>,
1109        cx: &mut ModelContext<Self>,
1110    ) {
1111        self.autoindent_requests.clear();
1112
1113        let edits: Vec<_> = indent_sizes
1114            .into_iter()
1115            .filter_map(|(row, indent_size)| {
1116                let current_size = indent_size_for_line(self, row);
1117                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1118            })
1119            .collect();
1120
1121        self.edit(edits, None, cx);
1122    }
1123
1124    // Create a minimal edit that will cause the the given row to be indented
1125    // with the given size. After applying this edit, the length of the line
1126    // will always be at least `new_size.len`.
1127    pub fn edit_for_indent_size_adjustment(
1128        row: u32,
1129        current_size: IndentSize,
1130        new_size: IndentSize,
1131    ) -> Option<(Range<Point>, String)> {
1132        if new_size.kind != current_size.kind {
1133            Some((
1134                Point::new(row, 0)..Point::new(row, current_size.len),
1135                iter::repeat(new_size.char())
1136                    .take(new_size.len as usize)
1137                    .collect::<String>(),
1138            ))
1139        } else {
1140            match new_size.len.cmp(&current_size.len) {
1141                Ordering::Greater => {
1142                    let point = Point::new(row, 0);
1143                    Some((
1144                        point..point,
1145                        iter::repeat(new_size.char())
1146                            .take((new_size.len - current_size.len) as usize)
1147                            .collect::<String>(),
1148                    ))
1149                }
1150
1151                Ordering::Less => Some((
1152                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1153                    String::new(),
1154                )),
1155
1156                Ordering::Equal => None,
1157            }
1158        }
1159    }
1160
1161    pub fn diff(&self, mut new_text: String, cx: &AppContext) -> Task<Diff> {
1162        let old_text = self.as_rope().clone();
1163        let base_version = self.version();
1164        cx.background().spawn(async move {
1165            let old_text = old_text.to_string();
1166            let line_ending = LineEnding::detect(&new_text);
1167            LineEnding::normalize(&mut new_text);
1168            let diff = TextDiff::from_chars(old_text.as_str(), new_text.as_str());
1169            let mut edits = Vec::new();
1170            let mut offset = 0;
1171            let empty: Arc<str> = "".into();
1172            for change in diff.iter_all_changes() {
1173                let value = change.value();
1174                let end_offset = offset + value.len();
1175                match change.tag() {
1176                    ChangeTag::Equal => {
1177                        offset = end_offset;
1178                    }
1179                    ChangeTag::Delete => {
1180                        edits.push((offset..end_offset, empty.clone()));
1181                        offset = end_offset;
1182                    }
1183                    ChangeTag::Insert => {
1184                        edits.push((offset..offset, value.into()));
1185                    }
1186                }
1187            }
1188            Diff {
1189                base_version,
1190                line_ending,
1191                edits,
1192            }
1193        })
1194    }
1195
1196    /// Spawn a background task that searches the buffer for any whitespace
1197    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1198    pub fn remove_trailing_whitespace(&self, cx: &AppContext) -> Task<Diff> {
1199        let old_text = self.as_rope().clone();
1200        let line_ending = self.line_ending();
1201        let base_version = self.version();
1202        cx.background().spawn(async move {
1203            let ranges = trailing_whitespace_ranges(&old_text);
1204            let empty = Arc::<str>::from("");
1205            Diff {
1206                base_version,
1207                line_ending,
1208                edits: ranges
1209                    .into_iter()
1210                    .map(|range| (range, empty.clone()))
1211                    .collect(),
1212            }
1213        })
1214    }
1215
1216    /// Ensure that the buffer ends with a single newline character, and
1217    /// no other whitespace.
1218    pub fn ensure_final_newline(&mut self, cx: &mut ModelContext<Self>) {
1219        let len = self.len();
1220        let mut offset = len;
1221        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1222            let non_whitespace_len = chunk
1223                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1224                .len();
1225            offset -= chunk.len();
1226            offset += non_whitespace_len;
1227            if non_whitespace_len != 0 {
1228                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1229                    return;
1230                }
1231                break;
1232            }
1233        }
1234        self.edit([(offset..len, "\n")], None, cx);
1235    }
1236
1237    /// Apply a diff to the buffer. If the buffer has changed since the given diff was
1238    /// calculated, then adjust the diff to account for those changes, and discard any
1239    /// parts of the diff that conflict with those changes.
1240    pub fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1241        // Check for any edits to the buffer that have occurred since this diff
1242        // was computed.
1243        let snapshot = self.snapshot();
1244        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1245        let mut delta = 0;
1246        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1247            while let Some(edit_since) = edits_since.peek() {
1248                // If the edit occurs after a diff hunk, then it does not
1249                // affect that hunk.
1250                if edit_since.old.start > range.end {
1251                    break;
1252                }
1253                // If the edit precedes the diff hunk, then adjust the hunk
1254                // to reflect the edit.
1255                else if edit_since.old.end < range.start {
1256                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1257                    edits_since.next();
1258                }
1259                // If the edit intersects a diff hunk, then discard that hunk.
1260                else {
1261                    return None;
1262                }
1263            }
1264
1265            let start = (range.start as i64 + delta) as usize;
1266            let end = (range.end as i64 + delta) as usize;
1267            Some((start..end, new_text))
1268        });
1269
1270        self.start_transaction();
1271        self.text.set_line_ending(diff.line_ending);
1272        self.edit(adjusted_edits, None, cx);
1273        self.end_transaction(cx)
1274    }
1275
1276    pub fn is_dirty(&self) -> bool {
1277        self.saved_version_fingerprint != self.as_rope().fingerprint()
1278            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1279    }
1280
1281    pub fn has_conflict(&self) -> bool {
1282        self.saved_version_fingerprint != self.as_rope().fingerprint()
1283            && self
1284                .file
1285                .as_ref()
1286                .map_or(false, |file| file.mtime() > self.saved_mtime)
1287    }
1288
1289    pub fn subscribe(&mut self) -> Subscription {
1290        self.text.subscribe()
1291    }
1292
1293    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1294        self.start_transaction_at(Instant::now())
1295    }
1296
1297    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1298        self.transaction_depth += 1;
1299        if self.was_dirty_before_starting_transaction.is_none() {
1300            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1301        }
1302        self.text.start_transaction_at(now)
1303    }
1304
1305    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1306        self.end_transaction_at(Instant::now(), cx)
1307    }
1308
1309    pub fn end_transaction_at(
1310        &mut self,
1311        now: Instant,
1312        cx: &mut ModelContext<Self>,
1313    ) -> Option<TransactionId> {
1314        assert!(self.transaction_depth > 0);
1315        self.transaction_depth -= 1;
1316        let was_dirty = if self.transaction_depth == 0 {
1317            self.was_dirty_before_starting_transaction.take().unwrap()
1318        } else {
1319            false
1320        };
1321        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1322            self.did_edit(&start_version, was_dirty, cx);
1323            Some(transaction_id)
1324        } else {
1325            None
1326        }
1327    }
1328
1329    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1330        self.text.push_transaction(transaction, now);
1331    }
1332
1333    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1334        self.text.finalize_last_transaction()
1335    }
1336
1337    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1338        self.text.group_until_transaction(transaction_id);
1339    }
1340
1341    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1342        self.text.forget_transaction(transaction_id);
1343    }
1344
1345    pub fn wait_for_edits(
1346        &mut self,
1347        edit_ids: impl IntoIterator<Item = clock::Local>,
1348    ) -> impl Future<Output = Result<()>> {
1349        self.text.wait_for_edits(edit_ids)
1350    }
1351
1352    pub fn wait_for_anchors(
1353        &mut self,
1354        anchors: impl IntoIterator<Item = Anchor>,
1355    ) -> impl 'static + Future<Output = Result<()>> {
1356        self.text.wait_for_anchors(anchors)
1357    }
1358
1359    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = Result<()>> {
1360        self.text.wait_for_version(version)
1361    }
1362
1363    pub fn give_up_waiting(&mut self) {
1364        self.text.give_up_waiting();
1365    }
1366
1367    pub fn set_active_selections(
1368        &mut self,
1369        selections: Arc<[Selection<Anchor>]>,
1370        line_mode: bool,
1371        cursor_shape: CursorShape,
1372        cx: &mut ModelContext<Self>,
1373    ) {
1374        let lamport_timestamp = self.text.lamport_clock.tick();
1375        self.remote_selections.insert(
1376            self.text.replica_id(),
1377            SelectionSet {
1378                selections: selections.clone(),
1379                lamport_timestamp,
1380                line_mode,
1381                cursor_shape,
1382            },
1383        );
1384        self.send_operation(
1385            Operation::UpdateSelections {
1386                selections,
1387                line_mode,
1388                lamport_timestamp,
1389                cursor_shape,
1390            },
1391            cx,
1392        );
1393    }
1394
1395    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1396        if self
1397            .remote_selections
1398            .get(&self.text.replica_id())
1399            .map_or(true, |set| !set.selections.is_empty())
1400        {
1401            self.set_active_selections(Arc::from([]), false, Default::default(), cx);
1402        }
1403    }
1404
1405    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1406    where
1407        T: Into<Arc<str>>,
1408    {
1409        self.autoindent_requests.clear();
1410        self.edit([(0..self.len(), text)], None, cx)
1411    }
1412
1413    pub fn edit<I, S, T>(
1414        &mut self,
1415        edits_iter: I,
1416        autoindent_mode: Option<AutoindentMode>,
1417        cx: &mut ModelContext<Self>,
1418    ) -> Option<clock::Local>
1419    where
1420        I: IntoIterator<Item = (Range<S>, T)>,
1421        S: ToOffset,
1422        T: Into<Arc<str>>,
1423    {
1424        // Skip invalid edits and coalesce contiguous ones.
1425        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1426        for (range, new_text) in edits_iter {
1427            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
1428            if range.start > range.end {
1429                mem::swap(&mut range.start, &mut range.end);
1430            }
1431            let new_text = new_text.into();
1432            if !new_text.is_empty() || !range.is_empty() {
1433                if let Some((prev_range, prev_text)) = edits.last_mut() {
1434                    if prev_range.end >= range.start {
1435                        prev_range.end = cmp::max(prev_range.end, range.end);
1436                        *prev_text = format!("{prev_text}{new_text}").into();
1437                    } else {
1438                        edits.push((range, new_text));
1439                    }
1440                } else {
1441                    edits.push((range, new_text));
1442                }
1443            }
1444        }
1445        if edits.is_empty() {
1446            return None;
1447        }
1448
1449        self.start_transaction();
1450        self.pending_autoindent.take();
1451        let autoindent_request = autoindent_mode
1452            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
1453
1454        let edit_operation = self.text.edit(edits.iter().cloned());
1455        let edit_id = edit_operation.local_timestamp();
1456
1457        if let Some((before_edit, mode)) = autoindent_request {
1458            let mut delta = 0isize;
1459            let entries = edits
1460                .into_iter()
1461                .enumerate()
1462                .zip(&edit_operation.as_edit().unwrap().new_text)
1463                .map(|((ix, (range, _)), new_text)| {
1464                    let new_text_length = new_text.len();
1465                    let old_start = range.start.to_point(&before_edit);
1466                    let new_start = (delta + range.start as isize) as usize;
1467                    delta += new_text_length as isize - (range.end as isize - range.start as isize);
1468
1469                    let mut range_of_insertion_to_indent = 0..new_text_length;
1470                    let mut first_line_is_new = false;
1471                    let mut original_indent_column = None;
1472
1473                    // When inserting an entire line at the beginning of an existing line,
1474                    // treat the insertion as new.
1475                    if new_text.contains('\n')
1476                        && old_start.column <= before_edit.indent_size_for_line(old_start.row).len
1477                    {
1478                        first_line_is_new = true;
1479                    }
1480
1481                    // When inserting text starting with a newline, avoid auto-indenting the
1482                    // previous line.
1483                    if new_text.starts_with('\n') {
1484                        range_of_insertion_to_indent.start += 1;
1485                        first_line_is_new = true;
1486                    }
1487
1488                    // Avoid auto-indenting after the insertion.
1489                    if let AutoindentMode::Block {
1490                        original_indent_columns,
1491                    } = &mode
1492                    {
1493                        original_indent_column =
1494                            Some(original_indent_columns.get(ix).copied().unwrap_or_else(|| {
1495                                indent_size_for_text(
1496                                    new_text[range_of_insertion_to_indent.clone()].chars(),
1497                                )
1498                                .len
1499                            }));
1500                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
1501                            range_of_insertion_to_indent.end -= 1;
1502                        }
1503                    }
1504
1505                    AutoindentRequestEntry {
1506                        first_line_is_new,
1507                        original_indent_column,
1508                        indent_size: before_edit.language_indent_size_at(range.start, cx),
1509                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
1510                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
1511                    }
1512                })
1513                .collect();
1514
1515            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1516                before_edit,
1517                entries,
1518                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
1519            }));
1520        }
1521
1522        self.end_transaction(cx);
1523        self.send_operation(Operation::Buffer(edit_operation), cx);
1524        Some(edit_id)
1525    }
1526
1527    fn did_edit(
1528        &mut self,
1529        old_version: &clock::Global,
1530        was_dirty: bool,
1531        cx: &mut ModelContext<Self>,
1532    ) {
1533        if self.edits_since::<usize>(old_version).next().is_none() {
1534            return;
1535        }
1536
1537        self.reparse(cx);
1538
1539        cx.emit(Event::Edited);
1540        if was_dirty != self.is_dirty() {
1541            cx.emit(Event::DirtyChanged);
1542        }
1543        cx.notify();
1544    }
1545
1546    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1547        &mut self,
1548        ops: I,
1549        cx: &mut ModelContext<Self>,
1550    ) -> Result<()> {
1551        self.pending_autoindent.take();
1552        let was_dirty = self.is_dirty();
1553        let old_version = self.version.clone();
1554        let mut deferred_ops = Vec::new();
1555        let buffer_ops = ops
1556            .into_iter()
1557            .filter_map(|op| match op {
1558                Operation::Buffer(op) => Some(op),
1559                _ => {
1560                    if self.can_apply_op(&op) {
1561                        self.apply_op(op, cx);
1562                    } else {
1563                        deferred_ops.push(op);
1564                    }
1565                    None
1566                }
1567            })
1568            .collect::<Vec<_>>();
1569        self.text.apply_ops(buffer_ops)?;
1570        self.deferred_ops.insert(deferred_ops);
1571        self.flush_deferred_ops(cx);
1572        self.did_edit(&old_version, was_dirty, cx);
1573        // Notify independently of whether the buffer was edited as the operations could include a
1574        // selection update.
1575        cx.notify();
1576        Ok(())
1577    }
1578
1579    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1580        let mut deferred_ops = Vec::new();
1581        for op in self.deferred_ops.drain().iter().cloned() {
1582            if self.can_apply_op(&op) {
1583                self.apply_op(op, cx);
1584            } else {
1585                deferred_ops.push(op);
1586            }
1587        }
1588        self.deferred_ops.insert(deferred_ops);
1589    }
1590
1591    fn can_apply_op(&self, operation: &Operation) -> bool {
1592        match operation {
1593            Operation::Buffer(_) => {
1594                unreachable!("buffer operations should never be applied at this layer")
1595            }
1596            Operation::UpdateDiagnostics {
1597                diagnostics: diagnostic_set,
1598                ..
1599            } => diagnostic_set.iter().all(|diagnostic| {
1600                self.text.can_resolve(&diagnostic.range.start)
1601                    && self.text.can_resolve(&diagnostic.range.end)
1602            }),
1603            Operation::UpdateSelections { selections, .. } => selections
1604                .iter()
1605                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1606            Operation::UpdateCompletionTriggers { .. } => true,
1607        }
1608    }
1609
1610    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1611        match operation {
1612            Operation::Buffer(_) => {
1613                unreachable!("buffer operations should never be applied at this layer")
1614            }
1615            Operation::UpdateDiagnostics {
1616                server_id,
1617                diagnostics: diagnostic_set,
1618                lamport_timestamp,
1619            } => {
1620                let snapshot = self.snapshot();
1621                self.apply_diagnostic_update(
1622                    server_id,
1623                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1624                    lamport_timestamp,
1625                    cx,
1626                );
1627            }
1628            Operation::UpdateSelections {
1629                selections,
1630                lamport_timestamp,
1631                line_mode,
1632                cursor_shape,
1633            } => {
1634                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1635                    if set.lamport_timestamp > lamport_timestamp {
1636                        return;
1637                    }
1638                }
1639
1640                self.remote_selections.insert(
1641                    lamport_timestamp.replica_id,
1642                    SelectionSet {
1643                        selections,
1644                        lamport_timestamp,
1645                        line_mode,
1646                        cursor_shape,
1647                    },
1648                );
1649                self.text.lamport_clock.observe(lamport_timestamp);
1650                self.selections_update_count += 1;
1651            }
1652            Operation::UpdateCompletionTriggers {
1653                triggers,
1654                lamport_timestamp,
1655            } => {
1656                self.completion_triggers = triggers;
1657                self.text.lamport_clock.observe(lamport_timestamp);
1658            }
1659        }
1660    }
1661
1662    fn apply_diagnostic_update(
1663        &mut self,
1664        server_id: LanguageServerId,
1665        diagnostics: DiagnosticSet,
1666        lamport_timestamp: clock::Lamport,
1667        cx: &mut ModelContext<Self>,
1668    ) {
1669        if lamport_timestamp > self.diagnostics_timestamp {
1670            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
1671            if diagnostics.len() == 0 {
1672                if let Ok(ix) = ix {
1673                    self.diagnostics.remove(ix);
1674                }
1675            } else {
1676                match ix {
1677                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
1678                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
1679                };
1680            }
1681            self.diagnostics_timestamp = lamport_timestamp;
1682            self.diagnostics_update_count += 1;
1683            self.text.lamport_clock.observe(lamport_timestamp);
1684            cx.notify();
1685            cx.emit(Event::DiagnosticsUpdated);
1686        }
1687    }
1688
1689    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1690        cx.emit(Event::Operation(operation));
1691    }
1692
1693    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1694        self.remote_selections.remove(&replica_id);
1695        cx.notify();
1696    }
1697
1698    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1699        let was_dirty = self.is_dirty();
1700        let old_version = self.version.clone();
1701
1702        if let Some((transaction_id, operation)) = self.text.undo() {
1703            self.send_operation(Operation::Buffer(operation), cx);
1704            self.did_edit(&old_version, was_dirty, cx);
1705            Some(transaction_id)
1706        } else {
1707            None
1708        }
1709    }
1710
1711    pub fn undo_to_transaction(
1712        &mut self,
1713        transaction_id: TransactionId,
1714        cx: &mut ModelContext<Self>,
1715    ) -> bool {
1716        let was_dirty = self.is_dirty();
1717        let old_version = self.version.clone();
1718
1719        let operations = self.text.undo_to_transaction(transaction_id);
1720        let undone = !operations.is_empty();
1721        for operation in operations {
1722            self.send_operation(Operation::Buffer(operation), cx);
1723        }
1724        if undone {
1725            self.did_edit(&old_version, was_dirty, cx)
1726        }
1727        undone
1728    }
1729
1730    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1731        let was_dirty = self.is_dirty();
1732        let old_version = self.version.clone();
1733
1734        if let Some((transaction_id, operation)) = self.text.redo() {
1735            self.send_operation(Operation::Buffer(operation), cx);
1736            self.did_edit(&old_version, was_dirty, cx);
1737            Some(transaction_id)
1738        } else {
1739            None
1740        }
1741    }
1742
1743    pub fn redo_to_transaction(
1744        &mut self,
1745        transaction_id: TransactionId,
1746        cx: &mut ModelContext<Self>,
1747    ) -> bool {
1748        let was_dirty = self.is_dirty();
1749        let old_version = self.version.clone();
1750
1751        let operations = self.text.redo_to_transaction(transaction_id);
1752        let redone = !operations.is_empty();
1753        for operation in operations {
1754            self.send_operation(Operation::Buffer(operation), cx);
1755        }
1756        if redone {
1757            self.did_edit(&old_version, was_dirty, cx)
1758        }
1759        redone
1760    }
1761
1762    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1763        self.completion_triggers = triggers.clone();
1764        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
1765        self.send_operation(
1766            Operation::UpdateCompletionTriggers {
1767                triggers,
1768                lamport_timestamp: self.completion_triggers_timestamp,
1769            },
1770            cx,
1771        );
1772        cx.notify();
1773    }
1774
1775    pub fn completion_triggers(&self) -> &[String] {
1776        &self.completion_triggers
1777    }
1778}
1779
1780#[cfg(any(test, feature = "test-support"))]
1781impl Buffer {
1782    pub fn edit_via_marked_text(
1783        &mut self,
1784        marked_string: &str,
1785        autoindent_mode: Option<AutoindentMode>,
1786        cx: &mut ModelContext<Self>,
1787    ) {
1788        let edits = self.edits_for_marked_text(marked_string);
1789        self.edit(edits, autoindent_mode, cx);
1790    }
1791
1792    pub fn set_group_interval(&mut self, group_interval: Duration) {
1793        self.text.set_group_interval(group_interval);
1794    }
1795
1796    pub fn randomly_edit<T>(
1797        &mut self,
1798        rng: &mut T,
1799        old_range_count: usize,
1800        cx: &mut ModelContext<Self>,
1801    ) where
1802        T: rand::Rng,
1803    {
1804        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
1805        let mut last_end = None;
1806        for _ in 0..old_range_count {
1807            if last_end.map_or(false, |last_end| last_end >= self.len()) {
1808                break;
1809            }
1810
1811            let new_start = last_end.map_or(0, |last_end| last_end + 1);
1812            let mut range = self.random_byte_range(new_start, rng);
1813            if rng.gen_bool(0.2) {
1814                mem::swap(&mut range.start, &mut range.end);
1815            }
1816            last_end = Some(range.end);
1817
1818            let new_text_len = rng.gen_range(0..10);
1819            let new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
1820
1821            edits.push((range, new_text));
1822        }
1823        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
1824        self.edit(edits, None, cx);
1825    }
1826
1827    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1828        let was_dirty = self.is_dirty();
1829        let old_version = self.version.clone();
1830
1831        let ops = self.text.randomly_undo_redo(rng);
1832        if !ops.is_empty() {
1833            for op in ops {
1834                self.send_operation(Operation::Buffer(op), cx);
1835                self.did_edit(&old_version, was_dirty, cx);
1836            }
1837        }
1838    }
1839}
1840
1841impl Entity for Buffer {
1842    type Event = Event;
1843}
1844
1845impl Deref for Buffer {
1846    type Target = TextBuffer;
1847
1848    fn deref(&self) -> &Self::Target {
1849        &self.text
1850    }
1851}
1852
1853impl BufferSnapshot {
1854    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
1855        indent_size_for_line(self, row)
1856    }
1857
1858    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &AppContext) -> IndentSize {
1859        let language_name = self.language_at(position).map(|language| language.name());
1860        let settings = language_settings(language_name.as_deref(), cx);
1861        if settings.hard_tabs {
1862            IndentSize::tab()
1863        } else {
1864            IndentSize::spaces(settings.tab_size.get())
1865        }
1866    }
1867
1868    pub fn suggested_indents(
1869        &self,
1870        rows: impl Iterator<Item = u32>,
1871        single_indent_size: IndentSize,
1872    ) -> BTreeMap<u32, IndentSize> {
1873        let mut result = BTreeMap::new();
1874
1875        for row_range in contiguous_ranges(rows, 10) {
1876            let suggestions = match self.suggest_autoindents(row_range.clone()) {
1877                Some(suggestions) => suggestions,
1878                _ => break,
1879            };
1880
1881            for (row, suggestion) in row_range.zip(suggestions) {
1882                let indent_size = if let Some(suggestion) = suggestion {
1883                    result
1884                        .get(&suggestion.basis_row)
1885                        .copied()
1886                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
1887                        .with_delta(suggestion.delta, single_indent_size)
1888                } else {
1889                    self.indent_size_for_line(row)
1890                };
1891
1892                result.insert(row, indent_size);
1893            }
1894        }
1895
1896        result
1897    }
1898
1899    fn suggest_autoindents(
1900        &self,
1901        row_range: Range<u32>,
1902    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
1903        let config = &self.language.as_ref()?.config;
1904        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1905
1906        // Find the suggested indentation ranges based on the syntax tree.
1907        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
1908        let end = Point::new(row_range.end, 0);
1909        let range = (start..end).to_offset(&self.text);
1910        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1911            Some(&grammar.indents_config.as_ref()?.query)
1912        });
1913        let indent_configs = matches
1914            .grammars()
1915            .iter()
1916            .map(|grammar| grammar.indents_config.as_ref().unwrap())
1917            .collect::<Vec<_>>();
1918
1919        let mut indent_ranges = Vec::<Range<Point>>::new();
1920        let mut outdent_positions = Vec::<Point>::new();
1921        while let Some(mat) = matches.peek() {
1922            let mut start: Option<Point> = None;
1923            let mut end: Option<Point> = None;
1924
1925            let config = &indent_configs[mat.grammar_index];
1926            for capture in mat.captures {
1927                if capture.index == config.indent_capture_ix {
1928                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1929                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1930                } else if Some(capture.index) == config.start_capture_ix {
1931                    start = Some(Point::from_ts_point(capture.node.end_position()));
1932                } else if Some(capture.index) == config.end_capture_ix {
1933                    end = Some(Point::from_ts_point(capture.node.start_position()));
1934                } else if Some(capture.index) == config.outdent_capture_ix {
1935                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
1936                }
1937            }
1938
1939            matches.advance();
1940            if let Some((start, end)) = start.zip(end) {
1941                if start.row == end.row {
1942                    continue;
1943                }
1944
1945                let range = start..end;
1946                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
1947                    Err(ix) => indent_ranges.insert(ix, range),
1948                    Ok(ix) => {
1949                        let prev_range = &mut indent_ranges[ix];
1950                        prev_range.end = prev_range.end.max(range.end);
1951                    }
1952                }
1953            }
1954        }
1955
1956        let mut error_ranges = Vec::<Range<Point>>::new();
1957        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1958            Some(&grammar.error_query)
1959        });
1960        while let Some(mat) = matches.peek() {
1961            let node = mat.captures[0].node;
1962            let start = Point::from_ts_point(node.start_position());
1963            let end = Point::from_ts_point(node.end_position());
1964            let range = start..end;
1965            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
1966                Ok(ix) | Err(ix) => ix,
1967            };
1968            let mut end_ix = ix;
1969            while let Some(existing_range) = error_ranges.get(end_ix) {
1970                if existing_range.end < end {
1971                    end_ix += 1;
1972                } else {
1973                    break;
1974                }
1975            }
1976            error_ranges.splice(ix..end_ix, [range]);
1977            matches.advance();
1978        }
1979
1980        outdent_positions.sort();
1981        for outdent_position in outdent_positions {
1982            // find the innermost indent range containing this outdent_position
1983            // set its end to the outdent position
1984            if let Some(range_to_truncate) = indent_ranges
1985                .iter_mut()
1986                .filter(|indent_range| indent_range.contains(&outdent_position))
1987                .last()
1988            {
1989                range_to_truncate.end = outdent_position;
1990            }
1991        }
1992
1993        // Find the suggested indentation increases and decreased based on regexes.
1994        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
1995        self.for_each_line(
1996            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
1997                ..Point::new(row_range.end, 0),
1998            |row, line| {
1999                if config
2000                    .decrease_indent_pattern
2001                    .as_ref()
2002                    .map_or(false, |regex| regex.is_match(line))
2003                {
2004                    indent_change_rows.push((row, Ordering::Less));
2005                }
2006                if config
2007                    .increase_indent_pattern
2008                    .as_ref()
2009                    .map_or(false, |regex| regex.is_match(line))
2010                {
2011                    indent_change_rows.push((row + 1, Ordering::Greater));
2012                }
2013            },
2014        );
2015
2016        let mut indent_changes = indent_change_rows.into_iter().peekable();
2017        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
2018            prev_non_blank_row.unwrap_or(0)
2019        } else {
2020            row_range.start.saturating_sub(1)
2021        };
2022        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
2023        Some(row_range.map(move |row| {
2024            let row_start = Point::new(row, self.indent_size_for_line(row).len);
2025
2026            let mut indent_from_prev_row = false;
2027            let mut outdent_from_prev_row = false;
2028            let mut outdent_to_row = u32::MAX;
2029
2030            while let Some((indent_row, delta)) = indent_changes.peek() {
2031                match indent_row.cmp(&row) {
2032                    Ordering::Equal => match delta {
2033                        Ordering::Less => outdent_from_prev_row = true,
2034                        Ordering::Greater => indent_from_prev_row = true,
2035                        _ => {}
2036                    },
2037
2038                    Ordering::Greater => break,
2039                    Ordering::Less => {}
2040                }
2041
2042                indent_changes.next();
2043            }
2044
2045            for range in &indent_ranges {
2046                if range.start.row >= row {
2047                    break;
2048                }
2049                if range.start.row == prev_row && range.end > row_start {
2050                    indent_from_prev_row = true;
2051                }
2052                if range.end > prev_row_start && range.end <= row_start {
2053                    outdent_to_row = outdent_to_row.min(range.start.row);
2054                }
2055            }
2056
2057            let within_error = error_ranges
2058                .iter()
2059                .any(|e| e.start.row < row && e.end > row_start);
2060
2061            let suggestion = if outdent_to_row == prev_row
2062                || (outdent_from_prev_row && indent_from_prev_row)
2063            {
2064                Some(IndentSuggestion {
2065                    basis_row: prev_row,
2066                    delta: Ordering::Equal,
2067                    within_error,
2068                })
2069            } else if indent_from_prev_row {
2070                Some(IndentSuggestion {
2071                    basis_row: prev_row,
2072                    delta: Ordering::Greater,
2073                    within_error,
2074                })
2075            } else if outdent_to_row < prev_row {
2076                Some(IndentSuggestion {
2077                    basis_row: outdent_to_row,
2078                    delta: Ordering::Equal,
2079                    within_error,
2080                })
2081            } else if outdent_from_prev_row {
2082                Some(IndentSuggestion {
2083                    basis_row: prev_row,
2084                    delta: Ordering::Less,
2085                    within_error,
2086                })
2087            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
2088            {
2089                Some(IndentSuggestion {
2090                    basis_row: prev_row,
2091                    delta: Ordering::Equal,
2092                    within_error,
2093                })
2094            } else {
2095                None
2096            };
2097
2098            prev_row = row;
2099            prev_row_start = row_start;
2100            suggestion
2101        }))
2102    }
2103
2104    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
2105        while row > 0 {
2106            row -= 1;
2107            if !self.is_line_blank(row) {
2108                return Some(row);
2109            }
2110        }
2111        None
2112    }
2113
2114    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
2115        let range = range.start.to_offset(self)..range.end.to_offset(self);
2116
2117        let mut syntax = None;
2118        let mut diagnostic_endpoints = Vec::new();
2119        if language_aware {
2120            let captures = self.syntax.captures(range.clone(), &self.text, |grammar| {
2121                grammar.highlights_query.as_ref()
2122            });
2123            let highlight_maps = captures
2124                .grammars()
2125                .into_iter()
2126                .map(|grammar| grammar.highlight_map())
2127                .collect();
2128            syntax = Some((captures, highlight_maps));
2129            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
2130                diagnostic_endpoints.push(DiagnosticEndpoint {
2131                    offset: entry.range.start,
2132                    is_start: true,
2133                    severity: entry.diagnostic.severity,
2134                    is_unnecessary: entry.diagnostic.is_unnecessary,
2135                });
2136                diagnostic_endpoints.push(DiagnosticEndpoint {
2137                    offset: entry.range.end,
2138                    is_start: false,
2139                    severity: entry.diagnostic.severity,
2140                    is_unnecessary: entry.diagnostic.is_unnecessary,
2141                });
2142            }
2143            diagnostic_endpoints
2144                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
2145        }
2146
2147        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostic_endpoints)
2148    }
2149
2150    pub fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
2151        let mut line = String::new();
2152        let mut row = range.start.row;
2153        for chunk in self
2154            .as_rope()
2155            .chunks_in_range(range.to_offset(self))
2156            .chain(["\n"])
2157        {
2158            for (newline_ix, text) in chunk.split('\n').enumerate() {
2159                if newline_ix > 0 {
2160                    callback(row, &line);
2161                    row += 1;
2162                    line.clear();
2163                }
2164                line.push_str(text);
2165            }
2166        }
2167    }
2168
2169    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
2170        let offset = position.to_offset(self);
2171        self.syntax
2172            .layers_for_range(offset..offset, &self.text)
2173            .filter(|l| l.node.end_byte() > offset)
2174            .last()
2175            .map(|info| info.language)
2176            .or(self.language.as_ref())
2177    }
2178
2179    pub fn settings_at<'a, D: ToOffset>(
2180        &self,
2181        position: D,
2182        cx: &'a AppContext,
2183    ) -> &'a LanguageSettings {
2184        let language = self.language_at(position);
2185        language_settings(language.map(|l| l.name()).as_deref(), cx)
2186    }
2187
2188    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
2189        let offset = position.to_offset(self);
2190
2191        if let Some(layer_info) = self
2192            .syntax
2193            .layers_for_range(offset..offset, &self.text)
2194            .filter(|l| l.node.end_byte() > offset)
2195            .last()
2196        {
2197            Some(LanguageScope {
2198                language: layer_info.language.clone(),
2199                override_id: layer_info.override_id(offset, &self.text),
2200            })
2201        } else {
2202            self.language.clone().map(|language| LanguageScope {
2203                language,
2204                override_id: None,
2205            })
2206        }
2207    }
2208
2209    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
2210        let mut start = start.to_offset(self);
2211        let mut end = start;
2212        let mut next_chars = self.chars_at(start).peekable();
2213        let mut prev_chars = self.reversed_chars_at(start).peekable();
2214        let word_kind = cmp::max(
2215            prev_chars.peek().copied().map(char_kind),
2216            next_chars.peek().copied().map(char_kind),
2217        );
2218
2219        for ch in prev_chars {
2220            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2221                start -= ch.len_utf8();
2222            } else {
2223                break;
2224            }
2225        }
2226
2227        for ch in next_chars {
2228            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2229                end += ch.len_utf8();
2230            } else {
2231                break;
2232            }
2233        }
2234
2235        (start..end, word_kind)
2236    }
2237
2238    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
2239        let range = range.start.to_offset(self)..range.end.to_offset(self);
2240        let mut result: Option<Range<usize>> = None;
2241        'outer: for layer in self.syntax.layers_for_range(range.clone(), &self.text) {
2242            let mut cursor = layer.node.walk();
2243
2244            // Descend to the first leaf that touches the start of the range,
2245            // and if the range is non-empty, extends beyond the start.
2246            while cursor.goto_first_child_for_byte(range.start).is_some() {
2247                if !range.is_empty() && cursor.node().end_byte() == range.start {
2248                    cursor.goto_next_sibling();
2249                }
2250            }
2251
2252            // Ascend to the smallest ancestor that strictly contains the range.
2253            loop {
2254                let node_range = cursor.node().byte_range();
2255                if node_range.start <= range.start
2256                    && node_range.end >= range.end
2257                    && node_range.len() > range.len()
2258                {
2259                    break;
2260                }
2261                if !cursor.goto_parent() {
2262                    continue 'outer;
2263                }
2264            }
2265
2266            let left_node = cursor.node();
2267            let mut layer_result = left_node.byte_range();
2268
2269            // For an empty range, try to find another node immediately to the right of the range.
2270            if left_node.end_byte() == range.start {
2271                let mut right_node = None;
2272                while !cursor.goto_next_sibling() {
2273                    if !cursor.goto_parent() {
2274                        break;
2275                    }
2276                }
2277
2278                while cursor.node().start_byte() == range.start {
2279                    right_node = Some(cursor.node());
2280                    if !cursor.goto_first_child() {
2281                        break;
2282                    }
2283                }
2284
2285                // If there is a candidate node on both sides of the (empty) range, then
2286                // decide between the two by favoring a named node over an anonymous token.
2287                // If both nodes are the same in that regard, favor the right one.
2288                if let Some(right_node) = right_node {
2289                    if right_node.is_named() || !left_node.is_named() {
2290                        layer_result = right_node.byte_range();
2291                    }
2292                }
2293            }
2294
2295            if let Some(previous_result) = &result {
2296                if previous_result.len() < layer_result.len() {
2297                    continue;
2298                }
2299            }
2300            result = Some(layer_result);
2301        }
2302
2303        result
2304    }
2305
2306    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
2307        self.outline_items_containing(0..self.len(), theme)
2308            .map(Outline::new)
2309    }
2310
2311    pub fn symbols_containing<T: ToOffset>(
2312        &self,
2313        position: T,
2314        theme: Option<&SyntaxTheme>,
2315    ) -> Option<Vec<OutlineItem<Anchor>>> {
2316        let position = position.to_offset(self);
2317        let mut items = self.outline_items_containing(
2318            position.saturating_sub(1)..self.len().min(position + 1),
2319            theme,
2320        )?;
2321        let mut prev_depth = None;
2322        items.retain(|item| {
2323            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
2324            prev_depth = Some(item.depth);
2325            result
2326        });
2327        Some(items)
2328    }
2329
2330    fn outline_items_containing(
2331        &self,
2332        range: Range<usize>,
2333        theme: Option<&SyntaxTheme>,
2334    ) -> Option<Vec<OutlineItem<Anchor>>> {
2335        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2336            grammar.outline_config.as_ref().map(|c| &c.query)
2337        });
2338        let configs = matches
2339            .grammars()
2340            .iter()
2341            .map(|g| g.outline_config.as_ref().unwrap())
2342            .collect::<Vec<_>>();
2343
2344        let mut stack = Vec::<Range<usize>>::new();
2345        let mut items = Vec::new();
2346        while let Some(mat) = matches.peek() {
2347            let config = &configs[mat.grammar_index];
2348            let item_node = mat.captures.iter().find_map(|cap| {
2349                if cap.index == config.item_capture_ix {
2350                    Some(cap.node)
2351                } else {
2352                    None
2353                }
2354            })?;
2355
2356            let item_range = item_node.byte_range();
2357            if item_range.end < range.start || item_range.start > range.end {
2358                matches.advance();
2359                continue;
2360            }
2361
2362            let mut buffer_ranges = Vec::new();
2363            for capture in mat.captures {
2364                let node_is_name;
2365                if capture.index == config.name_capture_ix {
2366                    node_is_name = true;
2367                } else if Some(capture.index) == config.context_capture_ix {
2368                    node_is_name = false;
2369                } else {
2370                    continue;
2371                }
2372
2373                let mut range = capture.node.start_byte()..capture.node.end_byte();
2374                let start = capture.node.start_position();
2375                if capture.node.end_position().row > start.row {
2376                    range.end =
2377                        range.start + self.line_len(start.row as u32) as usize - start.column;
2378                }
2379
2380                buffer_ranges.push((range, node_is_name));
2381            }
2382
2383            if buffer_ranges.is_empty() {
2384                continue;
2385            }
2386
2387            let mut text = String::new();
2388            let mut highlight_ranges = Vec::new();
2389            let mut name_ranges = Vec::new();
2390            let mut chunks = self.chunks(
2391                buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
2392                true,
2393            );
2394            for (buffer_range, is_name) in buffer_ranges {
2395                if !text.is_empty() {
2396                    text.push(' ');
2397                }
2398                if is_name {
2399                    let mut start = text.len();
2400                    let end = start + buffer_range.len();
2401
2402                    // When multiple names are captured, then the matcheable text
2403                    // includes the whitespace in between the names.
2404                    if !name_ranges.is_empty() {
2405                        start -= 1;
2406                    }
2407
2408                    name_ranges.push(start..end);
2409                }
2410
2411                let mut offset = buffer_range.start;
2412                chunks.seek(offset);
2413                for mut chunk in chunks.by_ref() {
2414                    if chunk.text.len() > buffer_range.end - offset {
2415                        chunk.text = &chunk.text[0..(buffer_range.end - offset)];
2416                        offset = buffer_range.end;
2417                    } else {
2418                        offset += chunk.text.len();
2419                    }
2420                    let style = chunk
2421                        .syntax_highlight_id
2422                        .zip(theme)
2423                        .and_then(|(highlight, theme)| highlight.style(theme));
2424                    if let Some(style) = style {
2425                        let start = text.len();
2426                        let end = start + chunk.text.len();
2427                        highlight_ranges.push((start..end, style));
2428                    }
2429                    text.push_str(chunk.text);
2430                    if offset >= buffer_range.end {
2431                        break;
2432                    }
2433                }
2434            }
2435
2436            matches.advance();
2437            while stack.last().map_or(false, |prev_range| {
2438                prev_range.start > item_range.start || prev_range.end < item_range.end
2439            }) {
2440                stack.pop();
2441            }
2442            stack.push(item_range.clone());
2443
2444            items.push(OutlineItem {
2445                depth: stack.len() - 1,
2446                range: self.anchor_after(item_range.start)..self.anchor_before(item_range.end),
2447                text,
2448                highlight_ranges,
2449                name_ranges,
2450            })
2451        }
2452        Some(items)
2453    }
2454
2455    /// Returns bracket range pairs overlapping or adjacent to `range`
2456    pub fn bracket_ranges<'a, T: ToOffset>(
2457        &'a self,
2458        range: Range<T>,
2459    ) -> impl Iterator<Item = (Range<usize>, Range<usize>)> + 'a {
2460        // Find bracket pairs that *inclusively* contain the given range.
2461        let range = range.start.to_offset(self).saturating_sub(1)
2462            ..self.len().min(range.end.to_offset(self) + 1);
2463
2464        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2465            grammar.brackets_config.as_ref().map(|c| &c.query)
2466        });
2467        let configs = matches
2468            .grammars()
2469            .iter()
2470            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
2471            .collect::<Vec<_>>();
2472
2473        iter::from_fn(move || {
2474            while let Some(mat) = matches.peek() {
2475                let mut open = None;
2476                let mut close = None;
2477                let config = &configs[mat.grammar_index];
2478                for capture in mat.captures {
2479                    if capture.index == config.open_capture_ix {
2480                        open = Some(capture.node.byte_range());
2481                    } else if capture.index == config.close_capture_ix {
2482                        close = Some(capture.node.byte_range());
2483                    }
2484                }
2485
2486                matches.advance();
2487
2488                let Some((open, close)) = open.zip(close) else { continue };
2489
2490                let bracket_range = open.start..=close.end;
2491                if !bracket_range.overlaps(&range) {
2492                    continue;
2493                }
2494
2495                return Some((open, close));
2496            }
2497            None
2498        })
2499    }
2500
2501    #[allow(clippy::type_complexity)]
2502    pub fn remote_selections_in_range(
2503        &self,
2504        range: Range<Anchor>,
2505    ) -> impl Iterator<
2506        Item = (
2507            ReplicaId,
2508            bool,
2509            CursorShape,
2510            impl Iterator<Item = &Selection<Anchor>> + '_,
2511        ),
2512    > + '_ {
2513        self.remote_selections
2514            .iter()
2515            .filter(|(replica_id, set)| {
2516                **replica_id != self.text.replica_id() && !set.selections.is_empty()
2517            })
2518            .map(move |(replica_id, set)| {
2519                let start_ix = match set.selections.binary_search_by(|probe| {
2520                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
2521                }) {
2522                    Ok(ix) | Err(ix) => ix,
2523                };
2524                let end_ix = match set.selections.binary_search_by(|probe| {
2525                    probe.start.cmp(&range.end, self).then(Ordering::Less)
2526                }) {
2527                    Ok(ix) | Err(ix) => ix,
2528                };
2529
2530                (
2531                    *replica_id,
2532                    set.line_mode,
2533                    set.cursor_shape,
2534                    set.selections[start_ix..end_ix].iter(),
2535                )
2536            })
2537    }
2538
2539    pub fn git_diff_hunks_in_row_range<'a>(
2540        &'a self,
2541        range: Range<u32>,
2542    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2543        self.git_diff.hunks_in_row_range(range, self)
2544    }
2545
2546    pub fn git_diff_hunks_intersecting_range<'a>(
2547        &'a self,
2548        range: Range<Anchor>,
2549    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2550        self.git_diff.hunks_intersecting_range(range, self)
2551    }
2552
2553    pub fn git_diff_hunks_intersecting_range_rev<'a>(
2554        &'a self,
2555        range: Range<Anchor>,
2556    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2557        self.git_diff.hunks_intersecting_range_rev(range, self)
2558    }
2559
2560    pub fn diagnostics_in_range<'a, T, O>(
2561        &'a self,
2562        search_range: Range<T>,
2563        reversed: bool,
2564    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2565    where
2566        T: 'a + Clone + ToOffset,
2567        O: 'a + FromAnchor + Ord,
2568    {
2569        let mut iterators: Vec<_> = self
2570            .diagnostics
2571            .iter()
2572            .map(|(_, collection)| {
2573                collection
2574                    .range::<T, O>(search_range.clone(), self, true, reversed)
2575                    .peekable()
2576            })
2577            .collect();
2578
2579        std::iter::from_fn(move || {
2580            let (next_ix, _) = iterators
2581                .iter_mut()
2582                .enumerate()
2583                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
2584                .min_by(|(_, a), (_, b)| a.range.start.cmp(&b.range.start))?;
2585            iterators[next_ix].next()
2586        })
2587    }
2588
2589    pub fn diagnostic_groups(
2590        &self,
2591        language_server_id: Option<LanguageServerId>,
2592    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
2593        let mut groups = Vec::new();
2594
2595        if let Some(language_server_id) = language_server_id {
2596            if let Ok(ix) = self
2597                .diagnostics
2598                .binary_search_by_key(&language_server_id, |e| e.0)
2599            {
2600                self.diagnostics[ix]
2601                    .1
2602                    .groups(language_server_id, &mut groups, self);
2603            }
2604        } else {
2605            for (language_server_id, diagnostics) in self.diagnostics.iter() {
2606                diagnostics.groups(*language_server_id, &mut groups, self);
2607            }
2608        }
2609
2610        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
2611            let a_start = &group_a.entries[group_a.primary_ix].range.start;
2612            let b_start = &group_b.entries[group_b.primary_ix].range.start;
2613            a_start.cmp(b_start, self).then_with(|| id_a.cmp(&id_b))
2614        });
2615
2616        groups
2617    }
2618
2619    pub fn diagnostic_group<'a, O>(
2620        &'a self,
2621        group_id: usize,
2622    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2623    where
2624        O: 'a + FromAnchor,
2625    {
2626        self.diagnostics
2627            .iter()
2628            .flat_map(move |(_, set)| set.group(group_id, self))
2629    }
2630
2631    pub fn diagnostics_update_count(&self) -> usize {
2632        self.diagnostics_update_count
2633    }
2634
2635    pub fn parse_count(&self) -> usize {
2636        self.parse_count
2637    }
2638
2639    pub fn selections_update_count(&self) -> usize {
2640        self.selections_update_count
2641    }
2642
2643    pub fn file(&self) -> Option<&Arc<dyn File>> {
2644        self.file.as_ref()
2645    }
2646
2647    pub fn resolve_file_path(&self, cx: &AppContext, include_root: bool) -> Option<PathBuf> {
2648        if let Some(file) = self.file() {
2649            if file.path().file_name().is_none() || include_root {
2650                Some(file.full_path(cx))
2651            } else {
2652                Some(file.path().to_path_buf())
2653            }
2654        } else {
2655            None
2656        }
2657    }
2658
2659    pub fn file_update_count(&self) -> usize {
2660        self.file_update_count
2661    }
2662
2663    pub fn git_diff_update_count(&self) -> usize {
2664        self.git_diff_update_count
2665    }
2666}
2667
2668fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
2669    indent_size_for_text(text.chars_at(Point::new(row, 0)))
2670}
2671
2672pub fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
2673    let mut result = IndentSize::spaces(0);
2674    for c in text {
2675        let kind = match c {
2676            ' ' => IndentKind::Space,
2677            '\t' => IndentKind::Tab,
2678            _ => break,
2679        };
2680        if result.len == 0 {
2681            result.kind = kind;
2682        }
2683        result.len += 1;
2684    }
2685    result
2686}
2687
2688impl Clone for BufferSnapshot {
2689    fn clone(&self) -> Self {
2690        Self {
2691            text: self.text.clone(),
2692            git_diff: self.git_diff.clone(),
2693            syntax: self.syntax.clone(),
2694            file: self.file.clone(),
2695            remote_selections: self.remote_selections.clone(),
2696            diagnostics: self.diagnostics.clone(),
2697            selections_update_count: self.selections_update_count,
2698            diagnostics_update_count: self.diagnostics_update_count,
2699            file_update_count: self.file_update_count,
2700            git_diff_update_count: self.git_diff_update_count,
2701            language: self.language.clone(),
2702            parse_count: self.parse_count,
2703        }
2704    }
2705}
2706
2707impl Deref for BufferSnapshot {
2708    type Target = text::BufferSnapshot;
2709
2710    fn deref(&self) -> &Self::Target {
2711        &self.text
2712    }
2713}
2714
2715unsafe impl<'a> Send for BufferChunks<'a> {}
2716
2717impl<'a> BufferChunks<'a> {
2718    pub(crate) fn new(
2719        text: &'a Rope,
2720        range: Range<usize>,
2721        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
2722        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
2723    ) -> Self {
2724        let mut highlights = None;
2725        if let Some((captures, highlight_maps)) = syntax {
2726            highlights = Some(BufferChunkHighlights {
2727                captures,
2728                next_capture: None,
2729                stack: Default::default(),
2730                highlight_maps,
2731            })
2732        }
2733
2734        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2735        let chunks = text.chunks_in_range(range.clone());
2736
2737        BufferChunks {
2738            range,
2739            chunks,
2740            diagnostic_endpoints,
2741            error_depth: 0,
2742            warning_depth: 0,
2743            information_depth: 0,
2744            hint_depth: 0,
2745            unnecessary_depth: 0,
2746            highlights,
2747        }
2748    }
2749
2750    pub fn seek(&mut self, offset: usize) {
2751        self.range.start = offset;
2752        self.chunks.seek(self.range.start);
2753        if let Some(highlights) = self.highlights.as_mut() {
2754            highlights
2755                .stack
2756                .retain(|(end_offset, _)| *end_offset > offset);
2757            if let Some(capture) = &highlights.next_capture {
2758                if offset >= capture.node.start_byte() {
2759                    let next_capture_end = capture.node.end_byte();
2760                    if offset < next_capture_end {
2761                        highlights.stack.push((
2762                            next_capture_end,
2763                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
2764                        ));
2765                    }
2766                    highlights.next_capture.take();
2767                }
2768            }
2769            highlights.captures.set_byte_range(self.range.clone());
2770        }
2771    }
2772
2773    pub fn offset(&self) -> usize {
2774        self.range.start
2775    }
2776
2777    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2778        let depth = match endpoint.severity {
2779            DiagnosticSeverity::ERROR => &mut self.error_depth,
2780            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2781            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2782            DiagnosticSeverity::HINT => &mut self.hint_depth,
2783            _ => return,
2784        };
2785        if endpoint.is_start {
2786            *depth += 1;
2787        } else {
2788            *depth -= 1;
2789        }
2790
2791        if endpoint.is_unnecessary {
2792            if endpoint.is_start {
2793                self.unnecessary_depth += 1;
2794            } else {
2795                self.unnecessary_depth -= 1;
2796            }
2797        }
2798    }
2799
2800    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2801        if self.error_depth > 0 {
2802            Some(DiagnosticSeverity::ERROR)
2803        } else if self.warning_depth > 0 {
2804            Some(DiagnosticSeverity::WARNING)
2805        } else if self.information_depth > 0 {
2806            Some(DiagnosticSeverity::INFORMATION)
2807        } else if self.hint_depth > 0 {
2808            Some(DiagnosticSeverity::HINT)
2809        } else {
2810            None
2811        }
2812    }
2813
2814    fn current_code_is_unnecessary(&self) -> bool {
2815        self.unnecessary_depth > 0
2816    }
2817}
2818
2819impl<'a> Iterator for BufferChunks<'a> {
2820    type Item = Chunk<'a>;
2821
2822    fn next(&mut self) -> Option<Self::Item> {
2823        let mut next_capture_start = usize::MAX;
2824        let mut next_diagnostic_endpoint = usize::MAX;
2825
2826        if let Some(highlights) = self.highlights.as_mut() {
2827            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2828                if *parent_capture_end <= self.range.start {
2829                    highlights.stack.pop();
2830                } else {
2831                    break;
2832                }
2833            }
2834
2835            if highlights.next_capture.is_none() {
2836                highlights.next_capture = highlights.captures.next();
2837            }
2838
2839            while let Some(capture) = highlights.next_capture.as_ref() {
2840                if self.range.start < capture.node.start_byte() {
2841                    next_capture_start = capture.node.start_byte();
2842                    break;
2843                } else {
2844                    let highlight_id =
2845                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
2846                    highlights
2847                        .stack
2848                        .push((capture.node.end_byte(), highlight_id));
2849                    highlights.next_capture = highlights.captures.next();
2850                }
2851            }
2852        }
2853
2854        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2855            if endpoint.offset <= self.range.start {
2856                self.update_diagnostic_depths(endpoint);
2857                self.diagnostic_endpoints.next();
2858            } else {
2859                next_diagnostic_endpoint = endpoint.offset;
2860                break;
2861            }
2862        }
2863
2864        if let Some(chunk) = self.chunks.peek() {
2865            let chunk_start = self.range.start;
2866            let mut chunk_end = (self.chunks.offset() + chunk.len())
2867                .min(next_capture_start)
2868                .min(next_diagnostic_endpoint);
2869            let mut highlight_id = None;
2870            if let Some(highlights) = self.highlights.as_ref() {
2871                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2872                    chunk_end = chunk_end.min(*parent_capture_end);
2873                    highlight_id = Some(*parent_highlight_id);
2874                }
2875            }
2876
2877            let slice =
2878                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2879            self.range.start = chunk_end;
2880            if self.range.start == self.chunks.offset() + chunk.len() {
2881                self.chunks.next().unwrap();
2882            }
2883
2884            Some(Chunk {
2885                text: slice,
2886                syntax_highlight_id: highlight_id,
2887                diagnostic_severity: self.current_diagnostic_severity(),
2888                is_unnecessary: self.current_code_is_unnecessary(),
2889                ..Default::default()
2890            })
2891        } else {
2892            None
2893        }
2894    }
2895}
2896
2897impl operation_queue::Operation for Operation {
2898    fn lamport_timestamp(&self) -> clock::Lamport {
2899        match self {
2900            Operation::Buffer(_) => {
2901                unreachable!("buffer operations should never be deferred at this layer")
2902            }
2903            Operation::UpdateDiagnostics {
2904                lamport_timestamp, ..
2905            }
2906            | Operation::UpdateSelections {
2907                lamport_timestamp, ..
2908            }
2909            | Operation::UpdateCompletionTriggers {
2910                lamport_timestamp, ..
2911            } => *lamport_timestamp,
2912        }
2913    }
2914}
2915
2916impl Default for Diagnostic {
2917    fn default() -> Self {
2918        Self {
2919            source: Default::default(),
2920            code: None,
2921            severity: DiagnosticSeverity::ERROR,
2922            message: Default::default(),
2923            group_id: 0,
2924            is_primary: false,
2925            is_valid: true,
2926            is_disk_based: false,
2927            is_unnecessary: false,
2928        }
2929    }
2930}
2931
2932impl IndentSize {
2933    pub fn spaces(len: u32) -> Self {
2934        Self {
2935            len,
2936            kind: IndentKind::Space,
2937        }
2938    }
2939
2940    pub fn tab() -> Self {
2941        Self {
2942            len: 1,
2943            kind: IndentKind::Tab,
2944        }
2945    }
2946
2947    pub fn chars(&self) -> impl Iterator<Item = char> {
2948        iter::repeat(self.char()).take(self.len as usize)
2949    }
2950
2951    pub fn char(&self) -> char {
2952        match self.kind {
2953            IndentKind::Space => ' ',
2954            IndentKind::Tab => '\t',
2955        }
2956    }
2957
2958    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
2959        match direction {
2960            Ordering::Less => {
2961                if self.kind == size.kind && self.len >= size.len {
2962                    self.len -= size.len;
2963                }
2964            }
2965            Ordering::Equal => {}
2966            Ordering::Greater => {
2967                if self.len == 0 {
2968                    self = size;
2969                } else if self.kind == size.kind {
2970                    self.len += size.len;
2971                }
2972            }
2973        }
2974        self
2975    }
2976}
2977
2978impl Completion {
2979    pub fn sort_key(&self) -> (usize, &str) {
2980        let kind_key = match self.lsp_completion.kind {
2981            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2982            _ => 1,
2983        };
2984        (kind_key, &self.label.text[self.label.filter_range.clone()])
2985    }
2986
2987    pub fn is_snippet(&self) -> bool {
2988        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2989    }
2990}
2991
2992pub fn contiguous_ranges(
2993    values: impl Iterator<Item = u32>,
2994    max_len: usize,
2995) -> impl Iterator<Item = Range<u32>> {
2996    let mut values = values;
2997    let mut current_range: Option<Range<u32>> = None;
2998    std::iter::from_fn(move || loop {
2999        if let Some(value) = values.next() {
3000            if let Some(range) = &mut current_range {
3001                if value == range.end && range.len() < max_len {
3002                    range.end += 1;
3003                    continue;
3004                }
3005            }
3006
3007            let prev_range = current_range.clone();
3008            current_range = Some(value..(value + 1));
3009            if prev_range.is_some() {
3010                return prev_range;
3011            }
3012        } else {
3013            return current_range.take();
3014        }
3015    })
3016}
3017
3018pub fn char_kind(c: char) -> CharKind {
3019    if c.is_whitespace() {
3020        CharKind::Whitespace
3021    } else if c.is_alphanumeric() || c == '_' {
3022        CharKind::Word
3023    } else {
3024        CharKind::Punctuation
3025    }
3026}
3027
3028/// Find all of the ranges of whitespace that occur at the ends of lines
3029/// in the given rope.
3030///
3031/// This could also be done with a regex search, but this implementation
3032/// avoids copying text.
3033pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
3034    let mut ranges = Vec::new();
3035
3036    let mut offset = 0;
3037    let mut prev_chunk_trailing_whitespace_range = 0..0;
3038    for chunk in rope.chunks() {
3039        let mut prev_line_trailing_whitespace_range = 0..0;
3040        for (i, line) in chunk.split('\n').enumerate() {
3041            let line_end_offset = offset + line.len();
3042            let trimmed_line_len = line.trim_end_matches(|c| matches!(c, ' ' | '\t')).len();
3043            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
3044
3045            if i == 0 && trimmed_line_len == 0 {
3046                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
3047            }
3048            if !prev_line_trailing_whitespace_range.is_empty() {
3049                ranges.push(prev_line_trailing_whitespace_range);
3050            }
3051
3052            offset = line_end_offset + 1;
3053            prev_line_trailing_whitespace_range = trailing_whitespace_range;
3054        }
3055
3056        offset -= 1;
3057        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
3058    }
3059
3060    if !prev_chunk_trailing_whitespace_range.is_empty() {
3061        ranges.push(prev_chunk_trailing_whitespace_range);
3062    }
3063
3064    ranges
3065}