buffer.rs

   1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, BracketPair, Grammar, Language, LanguageConfig, LanguageRegistry, PLAIN_TEXT,
   5};
   6use crate::{
   7    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   8    outline::OutlineItem,
   9    syntax_map::{
  10        SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxSnapshot, ToTreeSitterPoint,
  11    },
  12    CodeLabel, LanguageScope, Outline,
  13};
  14use anyhow::{anyhow, Result};
  15use clock::ReplicaId;
  16use fs::LineEnding;
  17use futures::FutureExt as _;
  18use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, MutableAppContext, Task};
  19use parking_lot::Mutex;
  20use settings::Settings;
  21use similar::{ChangeTag, TextDiff};
  22use smol::future::yield_now;
  23use std::{
  24    any::Any,
  25    cmp::{self, Ordering},
  26    collections::BTreeMap,
  27    ffi::OsStr,
  28    future::Future,
  29    iter::{self, Iterator, Peekable},
  30    mem,
  31    ops::{Deref, Range},
  32    path::{Path, PathBuf},
  33    str,
  34    sync::Arc,
  35    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  36    vec,
  37};
  38use sum_tree::TreeMap;
  39use text::operation_queue::OperationQueue;
  40pub use text::{Buffer as TextBuffer, BufferSnapshot as TextBufferSnapshot, Operation as _, *};
  41use theme::SyntaxTheme;
  42#[cfg(any(test, feature = "test-support"))]
  43use util::RandomCharIter;
  44use util::{RangeExt, TryFutureExt as _};
  45
  46#[cfg(any(test, feature = "test-support"))]
  47pub use {tree_sitter_rust, tree_sitter_typescript};
  48
  49pub use lsp::DiagnosticSeverity;
  50
  51struct GitDiffStatus {
  52    diff: git::diff::BufferDiff,
  53    update_in_progress: bool,
  54    update_requested: bool,
  55}
  56
  57pub struct Buffer {
  58    text: TextBuffer,
  59    diff_base: Option<String>,
  60    git_diff_status: GitDiffStatus,
  61    file: Option<Arc<dyn File>>,
  62    saved_version: clock::Global,
  63    saved_version_fingerprint: RopeFingerprint,
  64    saved_mtime: SystemTime,
  65    transaction_depth: usize,
  66    was_dirty_before_starting_transaction: Option<bool>,
  67    language: Option<Arc<Language>>,
  68    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  69    pending_autoindent: Option<Task<()>>,
  70    sync_parse_timeout: Duration,
  71    syntax_map: Mutex<SyntaxMap>,
  72    parsing_in_background: bool,
  73    parse_count: usize,
  74    diagnostics: DiagnosticSet,
  75    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  76    selections_update_count: usize,
  77    diagnostics_update_count: usize,
  78    diagnostics_timestamp: clock::Lamport,
  79    file_update_count: usize,
  80    git_diff_update_count: usize,
  81    completion_triggers: Vec<String>,
  82    completion_triggers_timestamp: clock::Lamport,
  83    deferred_ops: OperationQueue<Operation>,
  84}
  85
  86pub struct BufferSnapshot {
  87    text: text::BufferSnapshot,
  88    pub git_diff: git::diff::BufferDiff,
  89    pub(crate) syntax: SyntaxSnapshot,
  90    file: Option<Arc<dyn File>>,
  91    diagnostics: DiagnosticSet,
  92    diagnostics_update_count: usize,
  93    file_update_count: usize,
  94    git_diff_update_count: usize,
  95    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  96    selections_update_count: usize,
  97    language: Option<Arc<Language>>,
  98    parse_count: usize,
  99}
 100
 101#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 102pub struct IndentSize {
 103    pub len: u32,
 104    pub kind: IndentKind,
 105}
 106
 107#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 108pub enum IndentKind {
 109    #[default]
 110    Space,
 111    Tab,
 112}
 113
 114#[derive(Copy, Clone, PartialEq, Eq, Debug, Default)]
 115pub enum CursorShape {
 116    #[default]
 117    Bar,
 118    Block,
 119    Underscore,
 120    Hollow,
 121}
 122
 123#[derive(Clone, Debug)]
 124struct SelectionSet {
 125    line_mode: bool,
 126    cursor_shape: CursorShape,
 127    selections: Arc<[Selection<Anchor>]>,
 128    lamport_timestamp: clock::Lamport,
 129}
 130
 131#[derive(Clone, Debug, PartialEq, Eq)]
 132pub struct GroupId {
 133    source: Arc<str>,
 134    id: usize,
 135}
 136
 137#[derive(Clone, Debug, PartialEq, Eq)]
 138pub struct Diagnostic {
 139    pub code: Option<String>,
 140    pub severity: DiagnosticSeverity,
 141    pub message: String,
 142    pub group_id: usize,
 143    pub is_valid: bool,
 144    pub is_primary: bool,
 145    pub is_disk_based: bool,
 146    pub is_unnecessary: bool,
 147}
 148
 149#[derive(Clone, Debug)]
 150pub struct Completion {
 151    pub old_range: Range<Anchor>,
 152    pub new_text: String,
 153    pub label: CodeLabel,
 154    pub lsp_completion: lsp::CompletionItem,
 155}
 156
 157#[derive(Clone, Debug)]
 158pub struct CodeAction {
 159    pub range: Range<Anchor>,
 160    pub lsp_action: lsp::CodeAction,
 161}
 162
 163#[derive(Clone, Debug, PartialEq, Eq)]
 164pub enum Operation {
 165    Buffer(text::Operation),
 166    UpdateDiagnostics {
 167        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 168        lamport_timestamp: clock::Lamport,
 169    },
 170    UpdateSelections {
 171        selections: Arc<[Selection<Anchor>]>,
 172        lamport_timestamp: clock::Lamport,
 173        line_mode: bool,
 174        cursor_shape: CursorShape,
 175    },
 176    UpdateCompletionTriggers {
 177        triggers: Vec<String>,
 178        lamport_timestamp: clock::Lamport,
 179    },
 180}
 181
 182#[derive(Clone, Debug, PartialEq, Eq)]
 183pub enum Event {
 184    Operation(Operation),
 185    Edited,
 186    DirtyChanged,
 187    Saved,
 188    FileHandleChanged,
 189    Reloaded,
 190    Reparsed,
 191    DiagnosticsUpdated,
 192    Closed,
 193}
 194
 195pub trait File: Send + Sync {
 196    fn as_local(&self) -> Option<&dyn LocalFile>;
 197
 198    fn is_local(&self) -> bool {
 199        self.as_local().is_some()
 200    }
 201
 202    fn mtime(&self) -> SystemTime;
 203
 204    /// Returns the path of this file relative to the worktree's root directory.
 205    fn path(&self) -> &Arc<Path>;
 206
 207    /// Returns the path of this file relative to the worktree's parent directory (this means it
 208    /// includes the name of the worktree's root folder).
 209    fn full_path(&self, cx: &AppContext) -> PathBuf;
 210
 211    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 212    /// of its worktree, then this method will return the name of the worktree itself.
 213    fn file_name<'a>(&'a self, cx: &'a AppContext) -> &'a OsStr;
 214
 215    fn is_deleted(&self) -> bool;
 216
 217    fn as_any(&self) -> &dyn Any;
 218
 219    fn to_proto(&self) -> rpc::proto::File;
 220}
 221
 222pub trait LocalFile: File {
 223    /// Returns the absolute path of this file.
 224    fn abs_path(&self, cx: &AppContext) -> PathBuf;
 225
 226    fn load(&self, cx: &AppContext) -> Task<Result<String>>;
 227
 228    fn buffer_reloaded(
 229        &self,
 230        buffer_id: u64,
 231        version: &clock::Global,
 232        fingerprint: RopeFingerprint,
 233        line_ending: LineEnding,
 234        mtime: SystemTime,
 235        cx: &mut MutableAppContext,
 236    );
 237}
 238
 239#[derive(Clone, Debug)]
 240pub enum AutoindentMode {
 241    /// Indent each line of inserted text.
 242    EachLine,
 243    /// Apply the same indentation adjustment to all of the lines
 244    /// in a given insertion.
 245    Block {
 246        /// The original indentation level of the first line of each
 247        /// insertion, if it has been copied.
 248        original_indent_columns: Vec<u32>,
 249    },
 250}
 251
 252#[derive(Clone)]
 253struct AutoindentRequest {
 254    before_edit: BufferSnapshot,
 255    entries: Vec<AutoindentRequestEntry>,
 256    is_block_mode: bool,
 257}
 258
 259#[derive(Clone)]
 260struct AutoindentRequestEntry {
 261    /// A range of the buffer whose indentation should be adjusted.
 262    range: Range<Anchor>,
 263    /// Whether or not these lines should be considered brand new, for the
 264    /// purpose of auto-indent. When text is not new, its indentation will
 265    /// only be adjusted if the suggested indentation level has *changed*
 266    /// since the edit was made.
 267    first_line_is_new: bool,
 268    indent_size: IndentSize,
 269    original_indent_column: Option<u32>,
 270}
 271
 272#[derive(Debug)]
 273struct IndentSuggestion {
 274    basis_row: u32,
 275    delta: Ordering,
 276    within_error: bool,
 277}
 278
 279struct BufferChunkHighlights<'a> {
 280    captures: SyntaxMapCaptures<'a>,
 281    next_capture: Option<SyntaxMapCapture<'a>>,
 282    stack: Vec<(usize, HighlightId)>,
 283    highlight_maps: Vec<HighlightMap>,
 284}
 285
 286pub struct BufferChunks<'a> {
 287    range: Range<usize>,
 288    chunks: text::Chunks<'a>,
 289    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 290    error_depth: usize,
 291    warning_depth: usize,
 292    information_depth: usize,
 293    hint_depth: usize,
 294    unnecessary_depth: usize,
 295    highlights: Option<BufferChunkHighlights<'a>>,
 296}
 297
 298#[derive(Clone, Copy, Debug, Default)]
 299pub struct Chunk<'a> {
 300    pub text: &'a str,
 301    pub syntax_highlight_id: Option<HighlightId>,
 302    pub highlight_style: Option<HighlightStyle>,
 303    pub diagnostic_severity: Option<DiagnosticSeverity>,
 304    pub is_unnecessary: bool,
 305}
 306
 307pub struct Diff {
 308    pub(crate) base_version: clock::Global,
 309    line_ending: LineEnding,
 310    edits: Vec<(Range<usize>, Arc<str>)>,
 311}
 312
 313#[derive(Clone, Copy)]
 314pub(crate) struct DiagnosticEndpoint {
 315    offset: usize,
 316    is_start: bool,
 317    severity: DiagnosticSeverity,
 318    is_unnecessary: bool,
 319}
 320
 321#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 322pub enum CharKind {
 323    Punctuation,
 324    Whitespace,
 325    Word,
 326}
 327
 328impl CharKind {
 329    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 330        if treat_punctuation_as_word && self == CharKind::Punctuation {
 331            CharKind::Word
 332        } else {
 333            self
 334        }
 335    }
 336}
 337
 338impl Buffer {
 339    pub fn new<T: Into<String>>(
 340        replica_id: ReplicaId,
 341        base_text: T,
 342        cx: &mut ModelContext<Self>,
 343    ) -> Self {
 344        Self::build(
 345            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 346            None,
 347            None,
 348        )
 349    }
 350
 351    pub fn from_file<T: Into<String>>(
 352        replica_id: ReplicaId,
 353        base_text: T,
 354        diff_base: Option<T>,
 355        file: Arc<dyn File>,
 356        cx: &mut ModelContext<Self>,
 357    ) -> Self {
 358        Self::build(
 359            TextBuffer::new(replica_id, cx.model_id() as u64, base_text.into()),
 360            diff_base.map(|h| h.into().into_boxed_str().into()),
 361            Some(file),
 362        )
 363    }
 364
 365    pub fn from_proto(
 366        replica_id: ReplicaId,
 367        message: proto::BufferState,
 368        file: Option<Arc<dyn File>>,
 369    ) -> Result<Self> {
 370        let buffer = TextBuffer::new(replica_id, message.id, message.base_text);
 371        let mut this = Self::build(
 372            buffer,
 373            message.diff_base.map(|text| text.into_boxed_str().into()),
 374            file,
 375        );
 376        this.text.set_line_ending(proto::deserialize_line_ending(
 377            rpc::proto::LineEnding::from_i32(message.line_ending)
 378                .ok_or_else(|| anyhow!("missing line_ending"))?,
 379        ));
 380        this.saved_version = proto::deserialize_version(message.saved_version);
 381        this.saved_version_fingerprint =
 382            proto::deserialize_fingerprint(&message.saved_version_fingerprint)?;
 383        this.saved_mtime = message
 384            .saved_mtime
 385            .ok_or_else(|| anyhow!("invalid saved_mtime"))?
 386            .into();
 387        Ok(this)
 388    }
 389
 390    pub fn to_proto(&self) -> proto::BufferState {
 391        proto::BufferState {
 392            id: self.remote_id(),
 393            file: self.file.as_ref().map(|f| f.to_proto()),
 394            base_text: self.base_text().to_string(),
 395            diff_base: self.diff_base.as_ref().map(|h| h.to_string()),
 396            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 397            saved_version: proto::serialize_version(&self.saved_version),
 398            saved_version_fingerprint: proto::serialize_fingerprint(self.saved_version_fingerprint),
 399            saved_mtime: Some(self.saved_mtime.into()),
 400        }
 401    }
 402
 403    pub fn serialize_ops(
 404        &self,
 405        since: Option<clock::Global>,
 406        cx: &AppContext,
 407    ) -> Task<Vec<proto::Operation>> {
 408        let mut operations = Vec::new();
 409        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 410        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 411            proto::serialize_operation(&Operation::UpdateSelections {
 412                selections: set.selections.clone(),
 413                lamport_timestamp: set.lamport_timestamp,
 414                line_mode: set.line_mode,
 415                cursor_shape: set.cursor_shape,
 416            })
 417        }));
 418        operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 419            diagnostics: self.diagnostics.iter().cloned().collect(),
 420            lamport_timestamp: self.diagnostics_timestamp,
 421        }));
 422        operations.push(proto::serialize_operation(
 423            &Operation::UpdateCompletionTriggers {
 424                triggers: self.completion_triggers.clone(),
 425                lamport_timestamp: self.completion_triggers_timestamp,
 426            },
 427        ));
 428
 429        let text_operations = self.text.operations().clone();
 430        cx.background().spawn(async move {
 431            let since = since.unwrap_or_default();
 432            operations.extend(
 433                text_operations
 434                    .iter()
 435                    .filter(|(_, op)| !since.observed(op.local_timestamp()))
 436                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 437            );
 438            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 439            operations
 440        })
 441    }
 442
 443    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 444        self.set_language(Some(language), cx);
 445        self
 446    }
 447
 448    fn build(buffer: TextBuffer, diff_base: Option<String>, file: Option<Arc<dyn File>>) -> Self {
 449        let saved_mtime = if let Some(file) = file.as_ref() {
 450            file.mtime()
 451        } else {
 452            UNIX_EPOCH
 453        };
 454
 455        Self {
 456            saved_mtime,
 457            saved_version: buffer.version(),
 458            saved_version_fingerprint: buffer.as_rope().fingerprint(),
 459            transaction_depth: 0,
 460            was_dirty_before_starting_transaction: None,
 461            text: buffer,
 462            diff_base,
 463            git_diff_status: GitDiffStatus {
 464                diff: git::diff::BufferDiff::new(),
 465                update_in_progress: false,
 466                update_requested: false,
 467            },
 468            file,
 469            syntax_map: Mutex::new(SyntaxMap::new()),
 470            parsing_in_background: false,
 471            parse_count: 0,
 472            sync_parse_timeout: Duration::from_millis(1),
 473            autoindent_requests: Default::default(),
 474            pending_autoindent: Default::default(),
 475            language: None,
 476            remote_selections: Default::default(),
 477            selections_update_count: 0,
 478            diagnostics: Default::default(),
 479            diagnostics_update_count: 0,
 480            diagnostics_timestamp: Default::default(),
 481            file_update_count: 0,
 482            git_diff_update_count: 0,
 483            completion_triggers: Default::default(),
 484            completion_triggers_timestamp: Default::default(),
 485            deferred_ops: OperationQueue::new(),
 486        }
 487    }
 488
 489    pub fn snapshot(&self) -> BufferSnapshot {
 490        let text = self.text.snapshot();
 491        let mut syntax_map = self.syntax_map.lock();
 492        syntax_map.interpolate(&text);
 493        let syntax = syntax_map.snapshot();
 494
 495        BufferSnapshot {
 496            text,
 497            syntax,
 498            git_diff: self.git_diff_status.diff.clone(),
 499            file: self.file.clone(),
 500            remote_selections: self.remote_selections.clone(),
 501            diagnostics: self.diagnostics.clone(),
 502            diagnostics_update_count: self.diagnostics_update_count,
 503            file_update_count: self.file_update_count,
 504            git_diff_update_count: self.git_diff_update_count,
 505            language: self.language.clone(),
 506            parse_count: self.parse_count,
 507            selections_update_count: self.selections_update_count,
 508        }
 509    }
 510
 511    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 512        &self.text
 513    }
 514
 515    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 516        self.text.snapshot()
 517    }
 518
 519    pub fn file(&self) -> Option<&Arc<dyn File>> {
 520        self.file.as_ref()
 521    }
 522
 523    pub fn saved_version(&self) -> &clock::Global {
 524        &self.saved_version
 525    }
 526
 527    pub fn saved_version_fingerprint(&self) -> RopeFingerprint {
 528        self.saved_version_fingerprint
 529    }
 530
 531    pub fn saved_mtime(&self) -> SystemTime {
 532        self.saved_mtime
 533    }
 534
 535    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 536        self.syntax_map.lock().clear();
 537        self.language = language;
 538        self.reparse(cx);
 539    }
 540
 541    pub fn set_language_registry(&mut self, language_registry: Arc<LanguageRegistry>) {
 542        self.syntax_map
 543            .lock()
 544            .set_language_registry(language_registry);
 545    }
 546
 547    pub fn did_save(
 548        &mut self,
 549        version: clock::Global,
 550        fingerprint: RopeFingerprint,
 551        mtime: SystemTime,
 552        cx: &mut ModelContext<Self>,
 553    ) {
 554        self.saved_version = version;
 555        self.saved_version_fingerprint = fingerprint;
 556        self.saved_mtime = mtime;
 557        cx.emit(Event::Saved);
 558        cx.notify();
 559    }
 560
 561    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 562        cx.spawn(|this, mut cx| async move {
 563            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 564                let file = this.file.as_ref()?.as_local()?;
 565                Some((file.mtime(), file.load(cx)))
 566            }) {
 567                let new_text = new_text.await?;
 568                let diff = this
 569                    .read_with(&cx, |this, cx| this.diff(new_text, cx))
 570                    .await;
 571                this.update(&mut cx, |this, cx| {
 572                    if this.version() == diff.base_version {
 573                        this.finalize_last_transaction();
 574                        this.apply_diff(diff, cx);
 575                        if let Some(transaction) = this.finalize_last_transaction().cloned() {
 576                            this.did_reload(
 577                                this.version(),
 578                                this.as_rope().fingerprint(),
 579                                this.line_ending(),
 580                                new_mtime,
 581                                cx,
 582                            );
 583                            return Ok(Some(transaction));
 584                        }
 585                    }
 586                    Ok(None)
 587                })
 588            } else {
 589                Ok(None)
 590            }
 591        })
 592    }
 593
 594    pub fn did_reload(
 595        &mut self,
 596        version: clock::Global,
 597        fingerprint: RopeFingerprint,
 598        line_ending: LineEnding,
 599        mtime: SystemTime,
 600        cx: &mut ModelContext<Self>,
 601    ) {
 602        self.saved_version = version;
 603        self.saved_version_fingerprint = fingerprint;
 604        self.text.set_line_ending(line_ending);
 605        self.saved_mtime = mtime;
 606        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 607            file.buffer_reloaded(
 608                self.remote_id(),
 609                &self.saved_version,
 610                self.saved_version_fingerprint,
 611                self.line_ending(),
 612                self.saved_mtime,
 613                cx,
 614            );
 615        }
 616        self.git_diff_recalc(cx);
 617        cx.emit(Event::Reloaded);
 618        cx.notify();
 619    }
 620
 621    pub fn file_updated(
 622        &mut self,
 623        new_file: Arc<dyn File>,
 624        cx: &mut ModelContext<Self>,
 625    ) -> Task<()> {
 626        let mut file_changed = false;
 627        let mut task = Task::ready(());
 628
 629        if let Some(old_file) = self.file.as_ref() {
 630            if new_file.path() != old_file.path() {
 631                file_changed = true;
 632            }
 633
 634            if new_file.is_deleted() {
 635                if !old_file.is_deleted() {
 636                    file_changed = true;
 637                    if !self.is_dirty() {
 638                        cx.emit(Event::DirtyChanged);
 639                    }
 640                }
 641            } else {
 642                let new_mtime = new_file.mtime();
 643                if new_mtime != old_file.mtime() {
 644                    file_changed = true;
 645
 646                    if !self.is_dirty() {
 647                        let reload = self.reload(cx).log_err().map(drop);
 648                        task = cx.foreground().spawn(reload);
 649                    }
 650                }
 651            }
 652        } else {
 653            file_changed = true;
 654        };
 655
 656        if file_changed {
 657            self.file_update_count += 1;
 658            cx.emit(Event::FileHandleChanged);
 659            cx.notify();
 660        }
 661        self.file = Some(new_file);
 662        task
 663    }
 664
 665    pub fn diff_base(&self) -> Option<&str> {
 666        self.diff_base.as_deref()
 667    }
 668
 669    pub fn set_diff_base(&mut self, diff_base: Option<String>, cx: &mut ModelContext<Self>) {
 670        self.diff_base = diff_base;
 671        self.git_diff_recalc(cx);
 672    }
 673
 674    pub fn needs_git_diff_recalc(&self) -> bool {
 675        self.git_diff_status.diff.needs_update(self)
 676    }
 677
 678    pub fn git_diff_recalc(&mut self, cx: &mut ModelContext<Self>) {
 679        if self.git_diff_status.update_in_progress {
 680            self.git_diff_status.update_requested = true;
 681            return;
 682        }
 683
 684        if let Some(diff_base) = &self.diff_base {
 685            let snapshot = self.snapshot();
 686            let diff_base = diff_base.clone();
 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            cx.spawn_weak(|this, mut cx| async move {
 695                let buffer_diff = diff.await;
 696                if let Some(this) = this.upgrade(&cx) {
 697                    this.update(&mut cx, |this, cx| {
 698                        this.git_diff_status.diff = buffer_diff;
 699                        this.git_diff_update_count += 1;
 700                        cx.notify();
 701
 702                        this.git_diff_status.update_in_progress = false;
 703                        if this.git_diff_status.update_requested {
 704                            this.git_diff_recalc(cx);
 705                        }
 706                    })
 707                }
 708            })
 709            .detach()
 710        } else {
 711            let snapshot = self.snapshot();
 712            self.git_diff_status.diff.clear(&snapshot);
 713            self.git_diff_update_count += 1;
 714            cx.notify();
 715        }
 716    }
 717
 718    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 719        cx.emit(Event::Closed);
 720    }
 721
 722    pub fn language(&self) -> Option<&Arc<Language>> {
 723        self.language.as_ref()
 724    }
 725
 726    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
 727        let offset = position.to_offset(self);
 728        self.syntax_map
 729            .lock()
 730            .layers_for_range(offset..offset, &self.text)
 731            .last()
 732            .map(|info| info.language.clone())
 733            .or_else(|| self.language.clone())
 734    }
 735
 736    pub fn parse_count(&self) -> usize {
 737        self.parse_count
 738    }
 739
 740    pub fn selections_update_count(&self) -> usize {
 741        self.selections_update_count
 742    }
 743
 744    pub fn diagnostics_update_count(&self) -> usize {
 745        self.diagnostics_update_count
 746    }
 747
 748    pub fn file_update_count(&self) -> usize {
 749        self.file_update_count
 750    }
 751
 752    pub fn git_diff_update_count(&self) -> usize {
 753        self.git_diff_update_count
 754    }
 755
 756    #[cfg(any(test, feature = "test-support"))]
 757    pub fn is_parsing(&self) -> bool {
 758        self.parsing_in_background
 759    }
 760
 761    pub fn contains_unknown_injections(&self) -> bool {
 762        self.syntax_map.lock().contains_unknown_injections()
 763    }
 764
 765    #[cfg(test)]
 766    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 767        self.sync_parse_timeout = timeout;
 768    }
 769
 770    /// Called after an edit to synchronize the buffer's main parse tree with
 771    /// the buffer's new underlying state.
 772    ///
 773    /// Locks the syntax map and interpolates the edits since the last reparse
 774    /// into the foreground syntax tree.
 775    ///
 776    /// Then takes a stable snapshot of the syntax map before unlocking it.
 777    /// The snapshot with the interpolated edits is sent to a background thread,
 778    /// where we ask Tree-sitter to perform an incremental parse.
 779    ///
 780    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
 781    /// waiting on the parse to complete. As soon as it completes, we proceed
 782    /// synchronously, unless a 1ms timeout elapses.
 783    ///
 784    /// If we time out waiting on the parse, we spawn a second task waiting
 785    /// until the parse does complete and return with the interpolated tree still
 786    /// in the foreground. When the background parse completes, call back into
 787    /// the main thread and assign the foreground parse state.
 788    ///
 789    /// If the buffer or grammar changed since the start of the background parse,
 790    /// initiate an additional reparse recursively. To avoid concurrent parses
 791    /// for the same buffer, we only initiate a new parse if we are not already
 792    /// parsing in the background.
 793    pub fn reparse(&mut self, cx: &mut ModelContext<Self>) {
 794        if self.parsing_in_background {
 795            return;
 796        }
 797        let language = if let Some(language) = self.language.clone() {
 798            language
 799        } else {
 800            return;
 801        };
 802
 803        let text = self.text_snapshot();
 804        let parsed_version = self.version();
 805
 806        let mut syntax_map = self.syntax_map.lock();
 807        syntax_map.interpolate(&text);
 808        let language_registry = syntax_map.language_registry();
 809        let mut syntax_snapshot = syntax_map.snapshot();
 810        drop(syntax_map);
 811
 812        let parse_task = cx.background().spawn({
 813            let language = language.clone();
 814            let language_registry = language_registry.clone();
 815            async move {
 816                syntax_snapshot.reparse(&text, language_registry, language);
 817                syntax_snapshot
 818            }
 819        });
 820
 821        match cx
 822            .background()
 823            .block_with_timeout(self.sync_parse_timeout, parse_task)
 824        {
 825            Ok(new_syntax_snapshot) => {
 826                self.did_finish_parsing(new_syntax_snapshot, cx);
 827                return;
 828            }
 829            Err(parse_task) => {
 830                self.parsing_in_background = true;
 831                cx.spawn(move |this, mut cx| async move {
 832                    let new_syntax_map = parse_task.await;
 833                    this.update(&mut cx, move |this, cx| {
 834                        let grammar_changed =
 835                            this.language.as_ref().map_or(true, |current_language| {
 836                                !Arc::ptr_eq(&language, current_language)
 837                            });
 838                        let language_registry_changed = new_syntax_map
 839                            .contains_unknown_injections()
 840                            && language_registry.map_or(false, |registry| {
 841                                registry.version() != new_syntax_map.language_registry_version()
 842                            });
 843                        let parse_again = language_registry_changed
 844                            || grammar_changed
 845                            || this.version.changed_since(&parsed_version);
 846                        this.did_finish_parsing(new_syntax_map, cx);
 847                        this.parsing_in_background = false;
 848                        if parse_again {
 849                            this.reparse(cx);
 850                        }
 851                    });
 852                })
 853                .detach();
 854            }
 855        }
 856    }
 857
 858    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut ModelContext<Self>) {
 859        self.parse_count += 1;
 860        self.syntax_map.lock().did_parse(syntax_snapshot);
 861        self.request_autoindent(cx);
 862        cx.emit(Event::Reparsed);
 863        cx.notify();
 864    }
 865
 866    pub fn update_diagnostics(&mut self, diagnostics: DiagnosticSet, cx: &mut ModelContext<Self>) {
 867        let lamport_timestamp = self.text.lamport_clock.tick();
 868        let op = Operation::UpdateDiagnostics {
 869            diagnostics: diagnostics.iter().cloned().collect(),
 870            lamport_timestamp,
 871        };
 872        self.apply_diagnostic_update(diagnostics, lamport_timestamp, cx);
 873        self.send_operation(op, cx);
 874    }
 875
 876    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 877        if let Some(indent_sizes) = self.compute_autoindents() {
 878            let indent_sizes = cx.background().spawn(indent_sizes);
 879            match cx
 880                .background()
 881                .block_with_timeout(Duration::from_micros(500), indent_sizes)
 882            {
 883                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
 884                Err(indent_sizes) => {
 885                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 886                        let indent_sizes = indent_sizes.await;
 887                        this.update(&mut cx, |this, cx| {
 888                            this.apply_autoindents(indent_sizes, cx);
 889                        });
 890                    }));
 891                }
 892            }
 893        } else {
 894            self.autoindent_requests.clear();
 895        }
 896    }
 897
 898    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
 899        let max_rows_between_yields = 100;
 900        let snapshot = self.snapshot();
 901        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
 902            return None;
 903        }
 904
 905        let autoindent_requests = self.autoindent_requests.clone();
 906        Some(async move {
 907            let mut indent_sizes = BTreeMap::new();
 908            for request in autoindent_requests {
 909                // Resolve each edited range to its row in the current buffer and in the
 910                // buffer before this batch of edits.
 911                let mut row_ranges = Vec::new();
 912                let mut old_to_new_rows = BTreeMap::new();
 913                let mut language_indent_sizes_by_new_row = Vec::new();
 914                for entry in &request.entries {
 915                    let position = entry.range.start;
 916                    let new_row = position.to_point(&snapshot).row;
 917                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
 918                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
 919
 920                    if !entry.first_line_is_new {
 921                        let old_row = position.to_point(&request.before_edit).row;
 922                        old_to_new_rows.insert(old_row, new_row);
 923                    }
 924                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
 925                }
 926
 927                // Build a map containing the suggested indentation for each of the edited lines
 928                // with respect to the state of the buffer before these edits. This map is keyed
 929                // by the rows for these lines in the current state of the buffer.
 930                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
 931                let old_edited_ranges =
 932                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 933                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 934                let mut language_indent_size = IndentSize::default();
 935                for old_edited_range in old_edited_ranges {
 936                    let suggestions = request
 937                        .before_edit
 938                        .suggest_autoindents(old_edited_range.clone())
 939                        .into_iter()
 940                        .flatten();
 941                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 942                        if let Some(suggestion) = suggestion {
 943                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
 944
 945                            // Find the indent size based on the language for this row.
 946                            while let Some((row, size)) = language_indent_sizes.peek() {
 947                                if *row > new_row {
 948                                    break;
 949                                }
 950                                language_indent_size = *size;
 951                                language_indent_sizes.next();
 952                            }
 953
 954                            let suggested_indent = old_to_new_rows
 955                                .get(&suggestion.basis_row)
 956                                .and_then(|from_row| {
 957                                    Some(old_suggestions.get(from_row).copied()?.0)
 958                                })
 959                                .unwrap_or_else(|| {
 960                                    request
 961                                        .before_edit
 962                                        .indent_size_for_line(suggestion.basis_row)
 963                                })
 964                                .with_delta(suggestion.delta, language_indent_size);
 965                            old_suggestions
 966                                .insert(new_row, (suggested_indent, suggestion.within_error));
 967                        }
 968                    }
 969                    yield_now().await;
 970                }
 971
 972                // In block mode, only compute indentation suggestions for the first line
 973                // of each insertion. Otherwise, compute suggestions for every inserted line.
 974                let new_edited_row_ranges = contiguous_ranges(
 975                    row_ranges.iter().flat_map(|(range, _)| {
 976                        if request.is_block_mode {
 977                            range.start..range.start + 1
 978                        } else {
 979                            range.clone()
 980                        }
 981                    }),
 982                    max_rows_between_yields,
 983                );
 984
 985                // Compute new suggestions for each line, but only include them in the result
 986                // if they differ from the old suggestion for that line.
 987                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 988                let mut language_indent_size = IndentSize::default();
 989                for new_edited_row_range in new_edited_row_ranges {
 990                    let suggestions = snapshot
 991                        .suggest_autoindents(new_edited_row_range.clone())
 992                        .into_iter()
 993                        .flatten();
 994                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
 995                        if let Some(suggestion) = suggestion {
 996                            // Find the indent size based on the language for this row.
 997                            while let Some((row, size)) = language_indent_sizes.peek() {
 998                                if *row > new_row {
 999                                    break;
1000                                }
1001                                language_indent_size = *size;
1002                                language_indent_sizes.next();
1003                            }
1004
1005                            let suggested_indent = indent_sizes
1006                                .get(&suggestion.basis_row)
1007                                .copied()
1008                                .unwrap_or_else(|| {
1009                                    snapshot.indent_size_for_line(suggestion.basis_row)
1010                                })
1011                                .with_delta(suggestion.delta, language_indent_size);
1012                            if old_suggestions.get(&new_row).map_or(
1013                                true,
1014                                |(old_indentation, was_within_error)| {
1015                                    suggested_indent != *old_indentation
1016                                        && (!suggestion.within_error || *was_within_error)
1017                                },
1018                            ) {
1019                                indent_sizes.insert(new_row, suggested_indent);
1020                            }
1021                        }
1022                    }
1023                    yield_now().await;
1024                }
1025
1026                // For each block of inserted text, adjust the indentation of the remaining
1027                // lines of the block by the same amount as the first line was adjusted.
1028                if request.is_block_mode {
1029                    for (row_range, original_indent_column) in
1030                        row_ranges
1031                            .into_iter()
1032                            .filter_map(|(range, original_indent_column)| {
1033                                if range.len() > 1 {
1034                                    Some((range, original_indent_column?))
1035                                } else {
1036                                    None
1037                                }
1038                            })
1039                    {
1040                        let new_indent = indent_sizes
1041                            .get(&row_range.start)
1042                            .copied()
1043                            .unwrap_or_else(|| snapshot.indent_size_for_line(row_range.start));
1044                        let delta = new_indent.len as i64 - original_indent_column as i64;
1045                        if delta != 0 {
1046                            for row in row_range.skip(1) {
1047                                indent_sizes.entry(row).or_insert_with(|| {
1048                                    let mut size = snapshot.indent_size_for_line(row);
1049                                    if size.kind == new_indent.kind {
1050                                        match delta.cmp(&0) {
1051                                            Ordering::Greater => size.len += delta as u32,
1052                                            Ordering::Less => {
1053                                                size.len = size.len.saturating_sub(-delta as u32)
1054                                            }
1055                                            Ordering::Equal => {}
1056                                        }
1057                                    }
1058                                    size
1059                                });
1060                            }
1061                        }
1062                    }
1063                }
1064            }
1065
1066            indent_sizes
1067        })
1068    }
1069
1070    fn apply_autoindents(
1071        &mut self,
1072        indent_sizes: BTreeMap<u32, IndentSize>,
1073        cx: &mut ModelContext<Self>,
1074    ) {
1075        self.autoindent_requests.clear();
1076
1077        let edits: Vec<_> = indent_sizes
1078            .into_iter()
1079            .filter_map(|(row, indent_size)| {
1080                let current_size = indent_size_for_line(self, row);
1081                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1082            })
1083            .collect();
1084
1085        self.edit(edits, None, cx);
1086    }
1087
1088    // Create a minimal edit that will cause the the given row to be indented
1089    // with the given size. After applying this edit, the length of the line
1090    // will always be at least `new_size.len`.
1091    pub fn edit_for_indent_size_adjustment(
1092        row: u32,
1093        current_size: IndentSize,
1094        new_size: IndentSize,
1095    ) -> Option<(Range<Point>, String)> {
1096        if new_size.kind != current_size.kind {
1097            Some((
1098                Point::new(row, 0)..Point::new(row, current_size.len),
1099                iter::repeat(new_size.char())
1100                    .take(new_size.len as usize)
1101                    .collect::<String>(),
1102            ))
1103        } else {
1104            match new_size.len.cmp(&current_size.len) {
1105                Ordering::Greater => {
1106                    let point = Point::new(row, 0);
1107                    Some((
1108                        point..point,
1109                        iter::repeat(new_size.char())
1110                            .take((new_size.len - current_size.len) as usize)
1111                            .collect::<String>(),
1112                    ))
1113                }
1114
1115                Ordering::Less => Some((
1116                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1117                    String::new(),
1118                )),
1119
1120                Ordering::Equal => None,
1121            }
1122        }
1123    }
1124
1125    pub fn diff(&self, mut new_text: String, cx: &AppContext) -> Task<Diff> {
1126        let old_text = self.as_rope().clone();
1127        let base_version = self.version();
1128        cx.background().spawn(async move {
1129            let old_text = old_text.to_string();
1130            let line_ending = LineEnding::detect(&new_text);
1131            LineEnding::normalize(&mut new_text);
1132            let diff = TextDiff::from_chars(old_text.as_str(), new_text.as_str());
1133            let mut edits = Vec::new();
1134            let mut offset = 0;
1135            let empty: Arc<str> = "".into();
1136            for change in diff.iter_all_changes() {
1137                let value = change.value();
1138                let end_offset = offset + value.len();
1139                match change.tag() {
1140                    ChangeTag::Equal => {
1141                        offset = end_offset;
1142                    }
1143                    ChangeTag::Delete => {
1144                        edits.push((offset..end_offset, empty.clone()));
1145                        offset = end_offset;
1146                    }
1147                    ChangeTag::Insert => {
1148                        edits.push((offset..offset, value.into()));
1149                    }
1150                }
1151            }
1152            Diff {
1153                base_version,
1154                line_ending,
1155                edits,
1156            }
1157        })
1158    }
1159
1160    /// Spawn a background task that searches the buffer for any whitespace
1161    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1162    pub fn remove_trailing_whitespace(&self, cx: &AppContext) -> Task<Diff> {
1163        let old_text = self.as_rope().clone();
1164        let line_ending = self.line_ending();
1165        let base_version = self.version();
1166        cx.background().spawn(async move {
1167            let ranges = trailing_whitespace_ranges(&old_text);
1168            let empty = Arc::<str>::from("");
1169            Diff {
1170                base_version,
1171                line_ending,
1172                edits: ranges
1173                    .into_iter()
1174                    .map(|range| (range, empty.clone()))
1175                    .collect(),
1176            }
1177        })
1178    }
1179
1180    /// Ensure that the buffer ends with a single newline character, and
1181    /// no other whitespace.
1182    pub fn ensure_final_newline(&mut self, cx: &mut ModelContext<Self>) {
1183        let len = self.len();
1184        let mut offset = len;
1185        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1186            let non_whitespace_len = chunk
1187                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1188                .len();
1189            offset -= chunk.len();
1190            offset += non_whitespace_len;
1191            if non_whitespace_len != 0 {
1192                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1193                    return;
1194                }
1195                break;
1196            }
1197        }
1198        self.edit([(offset..len, "\n")], None, cx);
1199    }
1200
1201    /// Apply a diff to the buffer. If the buffer has changed since the given diff was
1202    /// calculated, then adjust the diff to account for those changes, and discard any
1203    /// parts of the diff that conflict with those changes.
1204    pub fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1205        // Check for any edits to the buffer that have occurred since this diff
1206        // was computed.
1207        let snapshot = self.snapshot();
1208        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1209        let mut delta = 0;
1210        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1211            while let Some(edit_since) = edits_since.peek() {
1212                // If the edit occurs after a diff hunk, then it does not
1213                // affect that hunk.
1214                if edit_since.old.start > range.end {
1215                    break;
1216                }
1217                // If the edit precedes the diff hunk, then adjust the hunk
1218                // to reflect the edit.
1219                else if edit_since.old.end < range.start {
1220                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1221                    edits_since.next();
1222                }
1223                // If the edit intersects a diff hunk, then discard that hunk.
1224                else {
1225                    return None;
1226                }
1227            }
1228
1229            let start = (range.start as i64 + delta) as usize;
1230            let end = (range.end as i64 + delta) as usize;
1231            Some((start..end, new_text))
1232        });
1233
1234        self.start_transaction();
1235        self.text.set_line_ending(diff.line_ending);
1236        self.edit(adjusted_edits, None, cx);
1237        self.end_transaction(cx)
1238    }
1239
1240    pub fn is_dirty(&self) -> bool {
1241        self.saved_version_fingerprint != self.as_rope().fingerprint()
1242            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1243    }
1244
1245    pub fn has_conflict(&self) -> bool {
1246        self.saved_version_fingerprint != self.as_rope().fingerprint()
1247            && self
1248                .file
1249                .as_ref()
1250                .map_or(false, |file| file.mtime() > self.saved_mtime)
1251    }
1252
1253    pub fn subscribe(&mut self) -> Subscription {
1254        self.text.subscribe()
1255    }
1256
1257    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1258        self.start_transaction_at(Instant::now())
1259    }
1260
1261    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1262        self.transaction_depth += 1;
1263        if self.was_dirty_before_starting_transaction.is_none() {
1264            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1265        }
1266        self.text.start_transaction_at(now)
1267    }
1268
1269    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1270        self.end_transaction_at(Instant::now(), cx)
1271    }
1272
1273    pub fn end_transaction_at(
1274        &mut self,
1275        now: Instant,
1276        cx: &mut ModelContext<Self>,
1277    ) -> Option<TransactionId> {
1278        assert!(self.transaction_depth > 0);
1279        self.transaction_depth -= 1;
1280        let was_dirty = if self.transaction_depth == 0 {
1281            self.was_dirty_before_starting_transaction.take().unwrap()
1282        } else {
1283            false
1284        };
1285        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1286            self.did_edit(&start_version, was_dirty, cx);
1287            Some(transaction_id)
1288        } else {
1289            None
1290        }
1291    }
1292
1293    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1294        self.text.push_transaction(transaction, now);
1295    }
1296
1297    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1298        self.text.finalize_last_transaction()
1299    }
1300
1301    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1302        self.text.group_until_transaction(transaction_id);
1303    }
1304
1305    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1306        self.text.forget_transaction(transaction_id);
1307    }
1308
1309    pub fn wait_for_edits(
1310        &mut self,
1311        edit_ids: impl IntoIterator<Item = clock::Local>,
1312    ) -> impl Future<Output = ()> {
1313        self.text.wait_for_edits(edit_ids)
1314    }
1315
1316    pub fn wait_for_anchors<'a>(
1317        &mut self,
1318        anchors: impl IntoIterator<Item = &'a Anchor>,
1319    ) -> impl Future<Output = ()> {
1320        self.text.wait_for_anchors(anchors)
1321    }
1322
1323    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = ()> {
1324        self.text.wait_for_version(version)
1325    }
1326
1327    pub fn set_active_selections(
1328        &mut self,
1329        selections: Arc<[Selection<Anchor>]>,
1330        line_mode: bool,
1331        cursor_shape: CursorShape,
1332        cx: &mut ModelContext<Self>,
1333    ) {
1334        let lamport_timestamp = self.text.lamport_clock.tick();
1335        self.remote_selections.insert(
1336            self.text.replica_id(),
1337            SelectionSet {
1338                selections: selections.clone(),
1339                lamport_timestamp,
1340                line_mode,
1341                cursor_shape,
1342            },
1343        );
1344        self.send_operation(
1345            Operation::UpdateSelections {
1346                selections,
1347                line_mode,
1348                lamport_timestamp,
1349                cursor_shape,
1350            },
1351            cx,
1352        );
1353    }
1354
1355    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1356        if self
1357            .remote_selections
1358            .get(&self.text.replica_id())
1359            .map_or(true, |set| !set.selections.is_empty())
1360        {
1361            self.set_active_selections(Arc::from([]), false, Default::default(), cx);
1362        }
1363    }
1364
1365    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1366    where
1367        T: Into<Arc<str>>,
1368    {
1369        self.autoindent_requests.clear();
1370        self.edit([(0..self.len(), text)], None, cx)
1371    }
1372
1373    pub fn edit<I, S, T>(
1374        &mut self,
1375        edits_iter: I,
1376        autoindent_mode: Option<AutoindentMode>,
1377        cx: &mut ModelContext<Self>,
1378    ) -> Option<clock::Local>
1379    where
1380        I: IntoIterator<Item = (Range<S>, T)>,
1381        S: ToOffset,
1382        T: Into<Arc<str>>,
1383    {
1384        // Skip invalid edits and coalesce contiguous ones.
1385        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1386        for (range, new_text) in edits_iter {
1387            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
1388            if range.start > range.end {
1389                mem::swap(&mut range.start, &mut range.end);
1390            }
1391            let new_text = new_text.into();
1392            if !new_text.is_empty() || !range.is_empty() {
1393                if let Some((prev_range, prev_text)) = edits.last_mut() {
1394                    if prev_range.end >= range.start {
1395                        prev_range.end = cmp::max(prev_range.end, range.end);
1396                        *prev_text = format!("{prev_text}{new_text}").into();
1397                    } else {
1398                        edits.push((range, new_text));
1399                    }
1400                } else {
1401                    edits.push((range, new_text));
1402                }
1403            }
1404        }
1405        if edits.is_empty() {
1406            return None;
1407        }
1408
1409        self.start_transaction();
1410        self.pending_autoindent.take();
1411        let autoindent_request = autoindent_mode
1412            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
1413
1414        let edit_operation = self.text.edit(edits.iter().cloned());
1415        let edit_id = edit_operation.local_timestamp();
1416
1417        if let Some((before_edit, mode)) = autoindent_request {
1418            let mut delta = 0isize;
1419            let entries = edits
1420                .into_iter()
1421                .enumerate()
1422                .zip(&edit_operation.as_edit().unwrap().new_text)
1423                .map(|((ix, (range, _)), new_text)| {
1424                    let new_text_length = new_text.len();
1425                    let old_start = range.start.to_point(&before_edit);
1426                    let new_start = (delta + range.start as isize) as usize;
1427                    delta += new_text_length as isize - (range.end as isize - range.start as isize);
1428
1429                    let mut range_of_insertion_to_indent = 0..new_text_length;
1430                    let mut first_line_is_new = false;
1431                    let mut original_indent_column = None;
1432
1433                    // When inserting an entire line at the beginning of an existing line,
1434                    // treat the insertion as new.
1435                    if new_text.contains('\n')
1436                        && old_start.column <= before_edit.indent_size_for_line(old_start.row).len
1437                    {
1438                        first_line_is_new = true;
1439                    }
1440
1441                    // When inserting text starting with a newline, avoid auto-indenting the
1442                    // previous line.
1443                    if new_text.starts_with('\n') {
1444                        range_of_insertion_to_indent.start += 1;
1445                        first_line_is_new = true;
1446                    }
1447
1448                    // Avoid auto-indenting after the insertion.
1449                    if let AutoindentMode::Block {
1450                        original_indent_columns,
1451                    } = &mode
1452                    {
1453                        original_indent_column =
1454                            Some(original_indent_columns.get(ix).copied().unwrap_or_else(|| {
1455                                indent_size_for_text(
1456                                    new_text[range_of_insertion_to_indent.clone()].chars(),
1457                                )
1458                                .len
1459                            }));
1460                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
1461                            range_of_insertion_to_indent.end -= 1;
1462                        }
1463                    }
1464
1465                    AutoindentRequestEntry {
1466                        first_line_is_new,
1467                        original_indent_column,
1468                        indent_size: before_edit.language_indent_size_at(range.start, cx),
1469                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
1470                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
1471                    }
1472                })
1473                .collect();
1474
1475            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1476                before_edit,
1477                entries,
1478                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
1479            }));
1480        }
1481
1482        self.end_transaction(cx);
1483        self.send_operation(Operation::Buffer(edit_operation), cx);
1484        Some(edit_id)
1485    }
1486
1487    fn did_edit(
1488        &mut self,
1489        old_version: &clock::Global,
1490        was_dirty: bool,
1491        cx: &mut ModelContext<Self>,
1492    ) {
1493        if self.edits_since::<usize>(old_version).next().is_none() {
1494            return;
1495        }
1496
1497        self.reparse(cx);
1498
1499        cx.emit(Event::Edited);
1500        if was_dirty != self.is_dirty() {
1501            cx.emit(Event::DirtyChanged);
1502        }
1503        cx.notify();
1504    }
1505
1506    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1507        &mut self,
1508        ops: I,
1509        cx: &mut ModelContext<Self>,
1510    ) -> Result<()> {
1511        self.pending_autoindent.take();
1512        let was_dirty = self.is_dirty();
1513        let old_version = self.version.clone();
1514        let mut deferred_ops = Vec::new();
1515        let buffer_ops = ops
1516            .into_iter()
1517            .filter_map(|op| match op {
1518                Operation::Buffer(op) => Some(op),
1519                _ => {
1520                    if self.can_apply_op(&op) {
1521                        self.apply_op(op, cx);
1522                    } else {
1523                        deferred_ops.push(op);
1524                    }
1525                    None
1526                }
1527            })
1528            .collect::<Vec<_>>();
1529        self.text.apply_ops(buffer_ops)?;
1530        self.deferred_ops.insert(deferred_ops);
1531        self.flush_deferred_ops(cx);
1532        self.did_edit(&old_version, was_dirty, cx);
1533        // Notify independently of whether the buffer was edited as the operations could include a
1534        // selection update.
1535        cx.notify();
1536        Ok(())
1537    }
1538
1539    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1540        let mut deferred_ops = Vec::new();
1541        for op in self.deferred_ops.drain().iter().cloned() {
1542            if self.can_apply_op(&op) {
1543                self.apply_op(op, cx);
1544            } else {
1545                deferred_ops.push(op);
1546            }
1547        }
1548        self.deferred_ops.insert(deferred_ops);
1549    }
1550
1551    fn can_apply_op(&self, operation: &Operation) -> bool {
1552        match operation {
1553            Operation::Buffer(_) => {
1554                unreachable!("buffer operations should never be applied at this layer")
1555            }
1556            Operation::UpdateDiagnostics {
1557                diagnostics: diagnostic_set,
1558                ..
1559            } => diagnostic_set.iter().all(|diagnostic| {
1560                self.text.can_resolve(&diagnostic.range.start)
1561                    && self.text.can_resolve(&diagnostic.range.end)
1562            }),
1563            Operation::UpdateSelections { selections, .. } => selections
1564                .iter()
1565                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1566            Operation::UpdateCompletionTriggers { .. } => true,
1567        }
1568    }
1569
1570    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1571        match operation {
1572            Operation::Buffer(_) => {
1573                unreachable!("buffer operations should never be applied at this layer")
1574            }
1575            Operation::UpdateDiagnostics {
1576                diagnostics: diagnostic_set,
1577                lamport_timestamp,
1578            } => {
1579                let snapshot = self.snapshot();
1580                self.apply_diagnostic_update(
1581                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1582                    lamport_timestamp,
1583                    cx,
1584                );
1585            }
1586            Operation::UpdateSelections {
1587                selections,
1588                lamport_timestamp,
1589                line_mode,
1590                cursor_shape,
1591            } => {
1592                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1593                    if set.lamport_timestamp > lamport_timestamp {
1594                        return;
1595                    }
1596                }
1597
1598                self.remote_selections.insert(
1599                    lamport_timestamp.replica_id,
1600                    SelectionSet {
1601                        selections,
1602                        lamport_timestamp,
1603                        line_mode,
1604                        cursor_shape,
1605                    },
1606                );
1607                self.text.lamport_clock.observe(lamport_timestamp);
1608                self.selections_update_count += 1;
1609            }
1610            Operation::UpdateCompletionTriggers {
1611                triggers,
1612                lamport_timestamp,
1613            } => {
1614                self.completion_triggers = triggers;
1615                self.text.lamport_clock.observe(lamport_timestamp);
1616            }
1617        }
1618    }
1619
1620    fn apply_diagnostic_update(
1621        &mut self,
1622        diagnostics: DiagnosticSet,
1623        lamport_timestamp: clock::Lamport,
1624        cx: &mut ModelContext<Self>,
1625    ) {
1626        if lamport_timestamp > self.diagnostics_timestamp {
1627            self.diagnostics = diagnostics;
1628            self.diagnostics_timestamp = lamport_timestamp;
1629            self.diagnostics_update_count += 1;
1630            self.text.lamport_clock.observe(lamport_timestamp);
1631            cx.notify();
1632            cx.emit(Event::DiagnosticsUpdated);
1633        }
1634    }
1635
1636    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1637        cx.emit(Event::Operation(operation));
1638    }
1639
1640    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1641        self.remote_selections.remove(&replica_id);
1642        cx.notify();
1643    }
1644
1645    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1646        let was_dirty = self.is_dirty();
1647        let old_version = self.version.clone();
1648
1649        if let Some((transaction_id, operation)) = self.text.undo() {
1650            self.send_operation(Operation::Buffer(operation), cx);
1651            self.did_edit(&old_version, was_dirty, cx);
1652            Some(transaction_id)
1653        } else {
1654            None
1655        }
1656    }
1657
1658    pub fn undo_to_transaction(
1659        &mut self,
1660        transaction_id: TransactionId,
1661        cx: &mut ModelContext<Self>,
1662    ) -> bool {
1663        let was_dirty = self.is_dirty();
1664        let old_version = self.version.clone();
1665
1666        let operations = self.text.undo_to_transaction(transaction_id);
1667        let undone = !operations.is_empty();
1668        for operation in operations {
1669            self.send_operation(Operation::Buffer(operation), cx);
1670        }
1671        if undone {
1672            self.did_edit(&old_version, was_dirty, cx)
1673        }
1674        undone
1675    }
1676
1677    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1678        let was_dirty = self.is_dirty();
1679        let old_version = self.version.clone();
1680
1681        if let Some((transaction_id, operation)) = self.text.redo() {
1682            self.send_operation(Operation::Buffer(operation), cx);
1683            self.did_edit(&old_version, was_dirty, cx);
1684            Some(transaction_id)
1685        } else {
1686            None
1687        }
1688    }
1689
1690    pub fn redo_to_transaction(
1691        &mut self,
1692        transaction_id: TransactionId,
1693        cx: &mut ModelContext<Self>,
1694    ) -> bool {
1695        let was_dirty = self.is_dirty();
1696        let old_version = self.version.clone();
1697
1698        let operations = self.text.redo_to_transaction(transaction_id);
1699        let redone = !operations.is_empty();
1700        for operation in operations {
1701            self.send_operation(Operation::Buffer(operation), cx);
1702        }
1703        if redone {
1704            self.did_edit(&old_version, was_dirty, cx)
1705        }
1706        redone
1707    }
1708
1709    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1710        self.completion_triggers = triggers.clone();
1711        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
1712        self.send_operation(
1713            Operation::UpdateCompletionTriggers {
1714                triggers,
1715                lamport_timestamp: self.completion_triggers_timestamp,
1716            },
1717            cx,
1718        );
1719        cx.notify();
1720    }
1721
1722    pub fn completion_triggers(&self) -> &[String] {
1723        &self.completion_triggers
1724    }
1725}
1726
1727#[cfg(any(test, feature = "test-support"))]
1728impl Buffer {
1729    pub fn edit_via_marked_text(
1730        &mut self,
1731        marked_string: &str,
1732        autoindent_mode: Option<AutoindentMode>,
1733        cx: &mut ModelContext<Self>,
1734    ) {
1735        let edits = self.edits_for_marked_text(marked_string);
1736        self.edit(edits, autoindent_mode, cx);
1737    }
1738
1739    pub fn set_group_interval(&mut self, group_interval: Duration) {
1740        self.text.set_group_interval(group_interval);
1741    }
1742
1743    pub fn randomly_edit<T>(
1744        &mut self,
1745        rng: &mut T,
1746        old_range_count: usize,
1747        cx: &mut ModelContext<Self>,
1748    ) where
1749        T: rand::Rng,
1750    {
1751        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
1752        let mut last_end = None;
1753        for _ in 0..old_range_count {
1754            if last_end.map_or(false, |last_end| last_end >= self.len()) {
1755                break;
1756            }
1757
1758            let new_start = last_end.map_or(0, |last_end| last_end + 1);
1759            let mut range = self.random_byte_range(new_start, rng);
1760            if rng.gen_bool(0.2) {
1761                mem::swap(&mut range.start, &mut range.end);
1762            }
1763            last_end = Some(range.end);
1764
1765            let new_text_len = rng.gen_range(0..10);
1766            let new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
1767
1768            edits.push((range, new_text));
1769        }
1770        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
1771        self.edit(edits, None, cx);
1772    }
1773
1774    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1775        let was_dirty = self.is_dirty();
1776        let old_version = self.version.clone();
1777
1778        let ops = self.text.randomly_undo_redo(rng);
1779        if !ops.is_empty() {
1780            for op in ops {
1781                self.send_operation(Operation::Buffer(op), cx);
1782                self.did_edit(&old_version, was_dirty, cx);
1783            }
1784        }
1785    }
1786}
1787
1788impl Entity for Buffer {
1789    type Event = Event;
1790}
1791
1792impl Deref for Buffer {
1793    type Target = TextBuffer;
1794
1795    fn deref(&self) -> &Self::Target {
1796        &self.text
1797    }
1798}
1799
1800impl BufferSnapshot {
1801    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
1802        indent_size_for_line(self, row)
1803    }
1804
1805    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &AppContext) -> IndentSize {
1806        let language_name = self.language_at(position).map(|language| language.name());
1807        let settings = cx.global::<Settings>();
1808        if settings.hard_tabs(language_name.as_deref()) {
1809            IndentSize::tab()
1810        } else {
1811            IndentSize::spaces(settings.tab_size(language_name.as_deref()).get())
1812        }
1813    }
1814
1815    pub fn suggested_indents(
1816        &self,
1817        rows: impl Iterator<Item = u32>,
1818        single_indent_size: IndentSize,
1819    ) -> BTreeMap<u32, IndentSize> {
1820        let mut result = BTreeMap::new();
1821
1822        for row_range in contiguous_ranges(rows, 10) {
1823            let suggestions = match self.suggest_autoindents(row_range.clone()) {
1824                Some(suggestions) => suggestions,
1825                _ => break,
1826            };
1827
1828            for (row, suggestion) in row_range.zip(suggestions) {
1829                let indent_size = if let Some(suggestion) = suggestion {
1830                    result
1831                        .get(&suggestion.basis_row)
1832                        .copied()
1833                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
1834                        .with_delta(suggestion.delta, single_indent_size)
1835                } else {
1836                    self.indent_size_for_line(row)
1837                };
1838
1839                result.insert(row, indent_size);
1840            }
1841        }
1842
1843        result
1844    }
1845
1846    fn suggest_autoindents(
1847        &self,
1848        row_range: Range<u32>,
1849    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
1850        let config = &self.language.as_ref()?.config;
1851        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1852
1853        // Find the suggested indentation ranges based on the syntax tree.
1854        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
1855        let end = Point::new(row_range.end, 0);
1856        let range = (start..end).to_offset(&self.text);
1857        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1858            Some(&grammar.indents_config.as_ref()?.query)
1859        });
1860        let indent_configs = matches
1861            .grammars()
1862            .iter()
1863            .map(|grammar| grammar.indents_config.as_ref().unwrap())
1864            .collect::<Vec<_>>();
1865
1866        let mut indent_ranges = Vec::<Range<Point>>::new();
1867        let mut outdent_positions = Vec::<Point>::new();
1868        while let Some(mat) = matches.peek() {
1869            let mut start: Option<Point> = None;
1870            let mut end: Option<Point> = None;
1871
1872            let config = &indent_configs[mat.grammar_index];
1873            for capture in mat.captures {
1874                if capture.index == config.indent_capture_ix {
1875                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1876                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1877                } else if Some(capture.index) == config.start_capture_ix {
1878                    start = Some(Point::from_ts_point(capture.node.end_position()));
1879                } else if Some(capture.index) == config.end_capture_ix {
1880                    end = Some(Point::from_ts_point(capture.node.start_position()));
1881                } else if Some(capture.index) == config.outdent_capture_ix {
1882                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
1883                }
1884            }
1885
1886            matches.advance();
1887            if let Some((start, end)) = start.zip(end) {
1888                if start.row == end.row {
1889                    continue;
1890                }
1891
1892                let range = start..end;
1893                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
1894                    Err(ix) => indent_ranges.insert(ix, range),
1895                    Ok(ix) => {
1896                        let prev_range = &mut indent_ranges[ix];
1897                        prev_range.end = prev_range.end.max(range.end);
1898                    }
1899                }
1900            }
1901        }
1902
1903        let mut error_ranges = Vec::<Range<Point>>::new();
1904        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1905            Some(&grammar.error_query)
1906        });
1907        while let Some(mat) = matches.peek() {
1908            let node = mat.captures[0].node;
1909            let start = Point::from_ts_point(node.start_position());
1910            let end = Point::from_ts_point(node.end_position());
1911            let range = start..end;
1912            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
1913                Ok(ix) | Err(ix) => ix,
1914            };
1915            let mut end_ix = ix;
1916            while let Some(existing_range) = error_ranges.get(end_ix) {
1917                if existing_range.end < end {
1918                    end_ix += 1;
1919                } else {
1920                    break;
1921                }
1922            }
1923            error_ranges.splice(ix..end_ix, [range]);
1924            matches.advance();
1925        }
1926
1927        outdent_positions.sort();
1928        for outdent_position in outdent_positions {
1929            // find the innermost indent range containing this outdent_position
1930            // set its end to the outdent position
1931            if let Some(range_to_truncate) = indent_ranges
1932                .iter_mut()
1933                .filter(|indent_range| indent_range.contains(&outdent_position))
1934                .last()
1935            {
1936                range_to_truncate.end = outdent_position;
1937            }
1938        }
1939
1940        // Find the suggested indentation increases and decreased based on regexes.
1941        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
1942        self.for_each_line(
1943            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
1944                ..Point::new(row_range.end, 0),
1945            |row, line| {
1946                if config
1947                    .decrease_indent_pattern
1948                    .as_ref()
1949                    .map_or(false, |regex| regex.is_match(line))
1950                {
1951                    indent_change_rows.push((row, Ordering::Less));
1952                }
1953                if config
1954                    .increase_indent_pattern
1955                    .as_ref()
1956                    .map_or(false, |regex| regex.is_match(line))
1957                {
1958                    indent_change_rows.push((row + 1, Ordering::Greater));
1959                }
1960            },
1961        );
1962
1963        let mut indent_changes = indent_change_rows.into_iter().peekable();
1964        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
1965            prev_non_blank_row.unwrap_or(0)
1966        } else {
1967            row_range.start.saturating_sub(1)
1968        };
1969        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
1970        Some(row_range.map(move |row| {
1971            let row_start = Point::new(row, self.indent_size_for_line(row).len);
1972
1973            let mut indent_from_prev_row = false;
1974            let mut outdent_from_prev_row = false;
1975            let mut outdent_to_row = u32::MAX;
1976
1977            while let Some((indent_row, delta)) = indent_changes.peek() {
1978                match indent_row.cmp(&row) {
1979                    Ordering::Equal => match delta {
1980                        Ordering::Less => outdent_from_prev_row = true,
1981                        Ordering::Greater => indent_from_prev_row = true,
1982                        _ => {}
1983                    },
1984
1985                    Ordering::Greater => break,
1986                    Ordering::Less => {}
1987                }
1988
1989                indent_changes.next();
1990            }
1991
1992            for range in &indent_ranges {
1993                if range.start.row >= row {
1994                    break;
1995                }
1996                if range.start.row == prev_row && range.end > row_start {
1997                    indent_from_prev_row = true;
1998                }
1999                if range.end > prev_row_start && range.end <= row_start {
2000                    outdent_to_row = outdent_to_row.min(range.start.row);
2001                }
2002            }
2003
2004            let within_error = error_ranges
2005                .iter()
2006                .any(|e| e.start.row < row && e.end > row_start);
2007
2008            let suggestion = if outdent_to_row == prev_row
2009                || (outdent_from_prev_row && indent_from_prev_row)
2010            {
2011                Some(IndentSuggestion {
2012                    basis_row: prev_row,
2013                    delta: Ordering::Equal,
2014                    within_error,
2015                })
2016            } else if indent_from_prev_row {
2017                Some(IndentSuggestion {
2018                    basis_row: prev_row,
2019                    delta: Ordering::Greater,
2020                    within_error,
2021                })
2022            } else if outdent_to_row < prev_row {
2023                Some(IndentSuggestion {
2024                    basis_row: outdent_to_row,
2025                    delta: Ordering::Equal,
2026                    within_error,
2027                })
2028            } else if outdent_from_prev_row {
2029                Some(IndentSuggestion {
2030                    basis_row: prev_row,
2031                    delta: Ordering::Less,
2032                    within_error,
2033                })
2034            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
2035            {
2036                Some(IndentSuggestion {
2037                    basis_row: prev_row,
2038                    delta: Ordering::Equal,
2039                    within_error,
2040                })
2041            } else {
2042                None
2043            };
2044
2045            prev_row = row;
2046            prev_row_start = row_start;
2047            suggestion
2048        }))
2049    }
2050
2051    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
2052        while row > 0 {
2053            row -= 1;
2054            if !self.is_line_blank(row) {
2055                return Some(row);
2056            }
2057        }
2058        None
2059    }
2060
2061    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
2062        let range = range.start.to_offset(self)..range.end.to_offset(self);
2063
2064        let mut syntax = None;
2065        let mut diagnostic_endpoints = Vec::new();
2066        if language_aware {
2067            let captures = self.syntax.captures(range.clone(), &self.text, |grammar| {
2068                grammar.highlights_query.as_ref()
2069            });
2070            let highlight_maps = captures
2071                .grammars()
2072                .into_iter()
2073                .map(|grammar| grammar.highlight_map())
2074                .collect();
2075            syntax = Some((captures, highlight_maps));
2076            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
2077                diagnostic_endpoints.push(DiagnosticEndpoint {
2078                    offset: entry.range.start,
2079                    is_start: true,
2080                    severity: entry.diagnostic.severity,
2081                    is_unnecessary: entry.diagnostic.is_unnecessary,
2082                });
2083                diagnostic_endpoints.push(DiagnosticEndpoint {
2084                    offset: entry.range.end,
2085                    is_start: false,
2086                    severity: entry.diagnostic.severity,
2087                    is_unnecessary: entry.diagnostic.is_unnecessary,
2088                });
2089            }
2090            diagnostic_endpoints
2091                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
2092        }
2093
2094        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostic_endpoints)
2095    }
2096
2097    pub fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
2098        let mut line = String::new();
2099        let mut row = range.start.row;
2100        for chunk in self
2101            .as_rope()
2102            .chunks_in_range(range.to_offset(self))
2103            .chain(["\n"])
2104        {
2105            for (newline_ix, text) in chunk.split('\n').enumerate() {
2106                if newline_ix > 0 {
2107                    callback(row, &line);
2108                    row += 1;
2109                    line.clear();
2110                }
2111                line.push_str(text);
2112            }
2113        }
2114    }
2115
2116    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
2117        let offset = position.to_offset(self);
2118        self.syntax
2119            .layers_for_range(offset..offset, &self.text)
2120            .filter(|l| l.node.end_byte() > offset)
2121            .last()
2122            .map(|info| info.language)
2123            .or(self.language.as_ref())
2124    }
2125
2126    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
2127        let offset = position.to_offset(self);
2128
2129        if let Some(layer_info) = self
2130            .syntax
2131            .layers_for_range(offset..offset, &self.text)
2132            .filter(|l| l.node.end_byte() > offset)
2133            .last()
2134        {
2135            Some(LanguageScope {
2136                language: layer_info.language.clone(),
2137                override_id: layer_info.override_id(offset, &self.text),
2138            })
2139        } else {
2140            self.language.clone().map(|language| LanguageScope {
2141                language,
2142                override_id: None,
2143            })
2144        }
2145    }
2146
2147    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
2148        let mut start = start.to_offset(self);
2149        let mut end = start;
2150        let mut next_chars = self.chars_at(start).peekable();
2151        let mut prev_chars = self.reversed_chars_at(start).peekable();
2152        let word_kind = cmp::max(
2153            prev_chars.peek().copied().map(char_kind),
2154            next_chars.peek().copied().map(char_kind),
2155        );
2156
2157        for ch in prev_chars {
2158            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2159                start -= ch.len_utf8();
2160            } else {
2161                break;
2162            }
2163        }
2164
2165        for ch in next_chars {
2166            if Some(char_kind(ch)) == word_kind && ch != '\n' {
2167                end += ch.len_utf8();
2168            } else {
2169                break;
2170            }
2171        }
2172
2173        (start..end, word_kind)
2174    }
2175
2176    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
2177        let range = range.start.to_offset(self)..range.end.to_offset(self);
2178        let mut result: Option<Range<usize>> = None;
2179        'outer: for layer in self.syntax.layers_for_range(range.clone(), &self.text) {
2180            let mut cursor = layer.node.walk();
2181
2182            // Descend to the first leaf that touches the start of the range,
2183            // and if the range is non-empty, extends beyond the start.
2184            while cursor.goto_first_child_for_byte(range.start).is_some() {
2185                if !range.is_empty() && cursor.node().end_byte() == range.start {
2186                    cursor.goto_next_sibling();
2187                }
2188            }
2189
2190            // Ascend to the smallest ancestor that strictly contains the range.
2191            loop {
2192                let node_range = cursor.node().byte_range();
2193                if node_range.start <= range.start
2194                    && node_range.end >= range.end
2195                    && node_range.len() > range.len()
2196                {
2197                    break;
2198                }
2199                if !cursor.goto_parent() {
2200                    continue 'outer;
2201                }
2202            }
2203
2204            let left_node = cursor.node();
2205            let mut layer_result = left_node.byte_range();
2206
2207            // For an empty range, try to find another node immediately to the right of the range.
2208            if left_node.end_byte() == range.start {
2209                let mut right_node = None;
2210                while !cursor.goto_next_sibling() {
2211                    if !cursor.goto_parent() {
2212                        break;
2213                    }
2214                }
2215
2216                while cursor.node().start_byte() == range.start {
2217                    right_node = Some(cursor.node());
2218                    if !cursor.goto_first_child() {
2219                        break;
2220                    }
2221                }
2222
2223                // If there is a candidate node on both sides of the (empty) range, then
2224                // decide between the two by favoring a named node over an anonymous token.
2225                // If both nodes are the same in that regard, favor the right one.
2226                if let Some(right_node) = right_node {
2227                    if right_node.is_named() || !left_node.is_named() {
2228                        layer_result = right_node.byte_range();
2229                    }
2230                }
2231            }
2232
2233            if let Some(previous_result) = &result {
2234                if previous_result.len() < layer_result.len() {
2235                    continue;
2236                }
2237            }
2238            result = Some(layer_result);
2239        }
2240
2241        result
2242    }
2243
2244    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
2245        self.outline_items_containing(0..self.len(), theme)
2246            .map(Outline::new)
2247    }
2248
2249    pub fn symbols_containing<T: ToOffset>(
2250        &self,
2251        position: T,
2252        theme: Option<&SyntaxTheme>,
2253    ) -> Option<Vec<OutlineItem<Anchor>>> {
2254        let position = position.to_offset(self);
2255        let mut items = self.outline_items_containing(
2256            position.saturating_sub(1)..self.len().min(position + 1),
2257            theme,
2258        )?;
2259        let mut prev_depth = None;
2260        items.retain(|item| {
2261            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
2262            prev_depth = Some(item.depth);
2263            result
2264        });
2265        Some(items)
2266    }
2267
2268    fn outline_items_containing(
2269        &self,
2270        range: Range<usize>,
2271        theme: Option<&SyntaxTheme>,
2272    ) -> Option<Vec<OutlineItem<Anchor>>> {
2273        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2274            grammar.outline_config.as_ref().map(|c| &c.query)
2275        });
2276        let configs = matches
2277            .grammars()
2278            .iter()
2279            .map(|g| g.outline_config.as_ref().unwrap())
2280            .collect::<Vec<_>>();
2281
2282        let mut stack = Vec::<Range<usize>>::new();
2283        let mut items = Vec::new();
2284        while let Some(mat) = matches.peek() {
2285            let config = &configs[mat.grammar_index];
2286            let item_node = mat.captures.iter().find_map(|cap| {
2287                if cap.index == config.item_capture_ix {
2288                    Some(cap.node)
2289                } else {
2290                    None
2291                }
2292            })?;
2293
2294            let item_range = item_node.byte_range();
2295            if item_range.end < range.start || item_range.start > range.end {
2296                matches.advance();
2297                continue;
2298            }
2299
2300            let mut buffer_ranges = Vec::new();
2301            for capture in mat.captures {
2302                let node_is_name;
2303                if capture.index == config.name_capture_ix {
2304                    node_is_name = true;
2305                } else if Some(capture.index) == config.context_capture_ix {
2306                    node_is_name = false;
2307                } else {
2308                    continue;
2309                }
2310
2311                let mut range = capture.node.start_byte()..capture.node.end_byte();
2312                let start = capture.node.start_position();
2313                if capture.node.end_position().row > start.row {
2314                    range.end =
2315                        range.start + self.line_len(start.row as u32) as usize - start.column;
2316                }
2317
2318                buffer_ranges.push((range, node_is_name));
2319            }
2320
2321            if buffer_ranges.is_empty() {
2322                continue;
2323            }
2324
2325            let mut text = String::new();
2326            let mut highlight_ranges = Vec::new();
2327            let mut name_ranges = Vec::new();
2328            let mut chunks = self.chunks(
2329                buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
2330                true,
2331            );
2332            for (buffer_range, is_name) in buffer_ranges {
2333                if !text.is_empty() {
2334                    text.push(' ');
2335                }
2336                if is_name {
2337                    let mut start = text.len();
2338                    let end = start + buffer_range.len();
2339
2340                    // When multiple names are captured, then the matcheable text
2341                    // includes the whitespace in between the names.
2342                    if !name_ranges.is_empty() {
2343                        start -= 1;
2344                    }
2345
2346                    name_ranges.push(start..end);
2347                }
2348
2349                let mut offset = buffer_range.start;
2350                chunks.seek(offset);
2351                for mut chunk in chunks.by_ref() {
2352                    if chunk.text.len() > buffer_range.end - offset {
2353                        chunk.text = &chunk.text[0..(buffer_range.end - offset)];
2354                        offset = buffer_range.end;
2355                    } else {
2356                        offset += chunk.text.len();
2357                    }
2358                    let style = chunk
2359                        .syntax_highlight_id
2360                        .zip(theme)
2361                        .and_then(|(highlight, theme)| highlight.style(theme));
2362                    if let Some(style) = style {
2363                        let start = text.len();
2364                        let end = start + chunk.text.len();
2365                        highlight_ranges.push((start..end, style));
2366                    }
2367                    text.push_str(chunk.text);
2368                    if offset >= buffer_range.end {
2369                        break;
2370                    }
2371                }
2372            }
2373
2374            matches.advance();
2375            while stack.last().map_or(false, |prev_range| {
2376                prev_range.start > item_range.start || prev_range.end < item_range.end
2377            }) {
2378                stack.pop();
2379            }
2380            stack.push(item_range.clone());
2381
2382            items.push(OutlineItem {
2383                depth: stack.len() - 1,
2384                range: self.anchor_after(item_range.start)..self.anchor_before(item_range.end),
2385                text,
2386                highlight_ranges,
2387                name_ranges,
2388            })
2389        }
2390        Some(items)
2391    }
2392
2393    /// Returns bracket range pairs overlapping or adjacent to `range`
2394    pub fn bracket_ranges<'a, T: ToOffset>(
2395        &'a self,
2396        range: Range<T>,
2397    ) -> impl Iterator<Item = (Range<usize>, Range<usize>)> + 'a {
2398        // Find bracket pairs that *inclusively* contain the given range.
2399        let range = range.start.to_offset(self).saturating_sub(1)
2400            ..self.len().min(range.end.to_offset(self) + 1);
2401
2402        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2403            grammar.brackets_config.as_ref().map(|c| &c.query)
2404        });
2405        let configs = matches
2406            .grammars()
2407            .iter()
2408            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
2409            .collect::<Vec<_>>();
2410
2411        iter::from_fn(move || {
2412            while let Some(mat) = matches.peek() {
2413                let mut open = None;
2414                let mut close = None;
2415                let config = &configs[mat.grammar_index];
2416                for capture in mat.captures {
2417                    if capture.index == config.open_capture_ix {
2418                        open = Some(capture.node.byte_range());
2419                    } else if capture.index == config.close_capture_ix {
2420                        close = Some(capture.node.byte_range());
2421                    }
2422                }
2423
2424                matches.advance();
2425
2426                let Some((open, close)) = open.zip(close) else { continue };
2427
2428                let bracket_range = open.start..=close.end;
2429                if !bracket_range.overlaps(&range) {
2430                    continue;
2431                }
2432
2433                return Some((open, close));
2434            }
2435            None
2436        })
2437    }
2438
2439    #[allow(clippy::type_complexity)]
2440    pub fn remote_selections_in_range(
2441        &self,
2442        range: Range<Anchor>,
2443    ) -> impl Iterator<
2444        Item = (
2445            ReplicaId,
2446            bool,
2447            CursorShape,
2448            impl Iterator<Item = &Selection<Anchor>> + '_,
2449        ),
2450    > + '_ {
2451        self.remote_selections
2452            .iter()
2453            .filter(|(replica_id, set)| {
2454                **replica_id != self.text.replica_id() && !set.selections.is_empty()
2455            })
2456            .map(move |(replica_id, set)| {
2457                let start_ix = match set.selections.binary_search_by(|probe| {
2458                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
2459                }) {
2460                    Ok(ix) | Err(ix) => ix,
2461                };
2462                let end_ix = match set.selections.binary_search_by(|probe| {
2463                    probe.start.cmp(&range.end, self).then(Ordering::Less)
2464                }) {
2465                    Ok(ix) | Err(ix) => ix,
2466                };
2467
2468                (
2469                    *replica_id,
2470                    set.line_mode,
2471                    set.cursor_shape,
2472                    set.selections[start_ix..end_ix].iter(),
2473                )
2474            })
2475    }
2476
2477    pub fn git_diff_hunks_in_row_range<'a>(
2478        &'a self,
2479        range: Range<u32>,
2480        reversed: bool,
2481    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2482        self.git_diff.hunks_in_row_range(range, self, reversed)
2483    }
2484
2485    pub fn git_diff_hunks_intersecting_range<'a>(
2486        &'a self,
2487        range: Range<Anchor>,
2488        reversed: bool,
2489    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2490        self.git_diff
2491            .hunks_intersecting_range(range, self, reversed)
2492    }
2493
2494    pub fn diagnostics_in_range<'a, T, O>(
2495        &'a self,
2496        search_range: Range<T>,
2497        reversed: bool,
2498    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2499    where
2500        T: 'a + Clone + ToOffset,
2501        O: 'a + FromAnchor,
2502    {
2503        self.diagnostics.range(search_range, self, true, reversed)
2504    }
2505
2506    pub fn diagnostic_groups(&self) -> Vec<DiagnosticGroup<Anchor>> {
2507        let mut groups = Vec::new();
2508        self.diagnostics.groups(&mut groups, self);
2509        groups
2510    }
2511
2512    pub fn diagnostic_group<'a, O>(
2513        &'a self,
2514        group_id: usize,
2515    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2516    where
2517        O: 'a + FromAnchor,
2518    {
2519        self.diagnostics.group(group_id, self)
2520    }
2521
2522    pub fn diagnostics_update_count(&self) -> usize {
2523        self.diagnostics_update_count
2524    }
2525
2526    pub fn parse_count(&self) -> usize {
2527        self.parse_count
2528    }
2529
2530    pub fn selections_update_count(&self) -> usize {
2531        self.selections_update_count
2532    }
2533
2534    pub fn file(&self) -> Option<&Arc<dyn File>> {
2535        self.file.as_ref()
2536    }
2537
2538    pub fn resolve_file_path(&self, cx: &AppContext, include_root: bool) -> Option<PathBuf> {
2539        if let Some(file) = self.file() {
2540            if file.path().file_name().is_none() || include_root {
2541                Some(file.full_path(cx))
2542            } else {
2543                Some(file.path().to_path_buf())
2544            }
2545        } else {
2546            None
2547        }
2548    }
2549
2550    pub fn file_update_count(&self) -> usize {
2551        self.file_update_count
2552    }
2553
2554    pub fn git_diff_update_count(&self) -> usize {
2555        self.git_diff_update_count
2556    }
2557}
2558
2559fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
2560    indent_size_for_text(text.chars_at(Point::new(row, 0)))
2561}
2562
2563pub fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
2564    let mut result = IndentSize::spaces(0);
2565    for c in text {
2566        let kind = match c {
2567            ' ' => IndentKind::Space,
2568            '\t' => IndentKind::Tab,
2569            _ => break,
2570        };
2571        if result.len == 0 {
2572            result.kind = kind;
2573        }
2574        result.len += 1;
2575    }
2576    result
2577}
2578
2579impl Clone for BufferSnapshot {
2580    fn clone(&self) -> Self {
2581        Self {
2582            text: self.text.clone(),
2583            git_diff: self.git_diff.clone(),
2584            syntax: self.syntax.clone(),
2585            file: self.file.clone(),
2586            remote_selections: self.remote_selections.clone(),
2587            diagnostics: self.diagnostics.clone(),
2588            selections_update_count: self.selections_update_count,
2589            diagnostics_update_count: self.diagnostics_update_count,
2590            file_update_count: self.file_update_count,
2591            git_diff_update_count: self.git_diff_update_count,
2592            language: self.language.clone(),
2593            parse_count: self.parse_count,
2594        }
2595    }
2596}
2597
2598impl Deref for BufferSnapshot {
2599    type Target = text::BufferSnapshot;
2600
2601    fn deref(&self) -> &Self::Target {
2602        &self.text
2603    }
2604}
2605
2606unsafe impl<'a> Send for BufferChunks<'a> {}
2607
2608impl<'a> BufferChunks<'a> {
2609    pub(crate) fn new(
2610        text: &'a Rope,
2611        range: Range<usize>,
2612        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
2613        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
2614    ) -> Self {
2615        let mut highlights = None;
2616        if let Some((captures, highlight_maps)) = syntax {
2617            highlights = Some(BufferChunkHighlights {
2618                captures,
2619                next_capture: None,
2620                stack: Default::default(),
2621                highlight_maps,
2622            })
2623        }
2624
2625        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2626        let chunks = text.chunks_in_range(range.clone());
2627
2628        BufferChunks {
2629            range,
2630            chunks,
2631            diagnostic_endpoints,
2632            error_depth: 0,
2633            warning_depth: 0,
2634            information_depth: 0,
2635            hint_depth: 0,
2636            unnecessary_depth: 0,
2637            highlights,
2638        }
2639    }
2640
2641    pub fn seek(&mut self, offset: usize) {
2642        self.range.start = offset;
2643        self.chunks.seek(self.range.start);
2644        if let Some(highlights) = self.highlights.as_mut() {
2645            highlights
2646                .stack
2647                .retain(|(end_offset, _)| *end_offset > offset);
2648            if let Some(capture) = &highlights.next_capture {
2649                if offset >= capture.node.start_byte() {
2650                    let next_capture_end = capture.node.end_byte();
2651                    if offset < next_capture_end {
2652                        highlights.stack.push((
2653                            next_capture_end,
2654                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
2655                        ));
2656                    }
2657                    highlights.next_capture.take();
2658                }
2659            }
2660            highlights.captures.set_byte_range(self.range.clone());
2661        }
2662    }
2663
2664    pub fn offset(&self) -> usize {
2665        self.range.start
2666    }
2667
2668    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2669        let depth = match endpoint.severity {
2670            DiagnosticSeverity::ERROR => &mut self.error_depth,
2671            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2672            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2673            DiagnosticSeverity::HINT => &mut self.hint_depth,
2674            _ => return,
2675        };
2676        if endpoint.is_start {
2677            *depth += 1;
2678        } else {
2679            *depth -= 1;
2680        }
2681
2682        if endpoint.is_unnecessary {
2683            if endpoint.is_start {
2684                self.unnecessary_depth += 1;
2685            } else {
2686                self.unnecessary_depth -= 1;
2687            }
2688        }
2689    }
2690
2691    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2692        if self.error_depth > 0 {
2693            Some(DiagnosticSeverity::ERROR)
2694        } else if self.warning_depth > 0 {
2695            Some(DiagnosticSeverity::WARNING)
2696        } else if self.information_depth > 0 {
2697            Some(DiagnosticSeverity::INFORMATION)
2698        } else if self.hint_depth > 0 {
2699            Some(DiagnosticSeverity::HINT)
2700        } else {
2701            None
2702        }
2703    }
2704
2705    fn current_code_is_unnecessary(&self) -> bool {
2706        self.unnecessary_depth > 0
2707    }
2708}
2709
2710impl<'a> Iterator for BufferChunks<'a> {
2711    type Item = Chunk<'a>;
2712
2713    fn next(&mut self) -> Option<Self::Item> {
2714        let mut next_capture_start = usize::MAX;
2715        let mut next_diagnostic_endpoint = usize::MAX;
2716
2717        if let Some(highlights) = self.highlights.as_mut() {
2718            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2719                if *parent_capture_end <= self.range.start {
2720                    highlights.stack.pop();
2721                } else {
2722                    break;
2723                }
2724            }
2725
2726            if highlights.next_capture.is_none() {
2727                highlights.next_capture = highlights.captures.next();
2728            }
2729
2730            while let Some(capture) = highlights.next_capture.as_ref() {
2731                if self.range.start < capture.node.start_byte() {
2732                    next_capture_start = capture.node.start_byte();
2733                    break;
2734                } else {
2735                    let highlight_id =
2736                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
2737                    highlights
2738                        .stack
2739                        .push((capture.node.end_byte(), highlight_id));
2740                    highlights.next_capture = highlights.captures.next();
2741                }
2742            }
2743        }
2744
2745        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2746            if endpoint.offset <= self.range.start {
2747                self.update_diagnostic_depths(endpoint);
2748                self.diagnostic_endpoints.next();
2749            } else {
2750                next_diagnostic_endpoint = endpoint.offset;
2751                break;
2752            }
2753        }
2754
2755        if let Some(chunk) = self.chunks.peek() {
2756            let chunk_start = self.range.start;
2757            let mut chunk_end = (self.chunks.offset() + chunk.len())
2758                .min(next_capture_start)
2759                .min(next_diagnostic_endpoint);
2760            let mut highlight_id = None;
2761            if let Some(highlights) = self.highlights.as_ref() {
2762                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2763                    chunk_end = chunk_end.min(*parent_capture_end);
2764                    highlight_id = Some(*parent_highlight_id);
2765                }
2766            }
2767
2768            let slice =
2769                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2770            self.range.start = chunk_end;
2771            if self.range.start == self.chunks.offset() + chunk.len() {
2772                self.chunks.next().unwrap();
2773            }
2774
2775            Some(Chunk {
2776                text: slice,
2777                syntax_highlight_id: highlight_id,
2778                highlight_style: None,
2779                diagnostic_severity: self.current_diagnostic_severity(),
2780                is_unnecessary: self.current_code_is_unnecessary(),
2781            })
2782        } else {
2783            None
2784        }
2785    }
2786}
2787
2788impl operation_queue::Operation for Operation {
2789    fn lamport_timestamp(&self) -> clock::Lamport {
2790        match self {
2791            Operation::Buffer(_) => {
2792                unreachable!("buffer operations should never be deferred at this layer")
2793            }
2794            Operation::UpdateDiagnostics {
2795                lamport_timestamp, ..
2796            }
2797            | Operation::UpdateSelections {
2798                lamport_timestamp, ..
2799            }
2800            | Operation::UpdateCompletionTriggers {
2801                lamport_timestamp, ..
2802            } => *lamport_timestamp,
2803        }
2804    }
2805}
2806
2807impl Default for Diagnostic {
2808    fn default() -> Self {
2809        Self {
2810            code: None,
2811            severity: DiagnosticSeverity::ERROR,
2812            message: Default::default(),
2813            group_id: 0,
2814            is_primary: false,
2815            is_valid: true,
2816            is_disk_based: false,
2817            is_unnecessary: false,
2818        }
2819    }
2820}
2821
2822impl IndentSize {
2823    pub fn spaces(len: u32) -> Self {
2824        Self {
2825            len,
2826            kind: IndentKind::Space,
2827        }
2828    }
2829
2830    pub fn tab() -> Self {
2831        Self {
2832            len: 1,
2833            kind: IndentKind::Tab,
2834        }
2835    }
2836
2837    pub fn chars(&self) -> impl Iterator<Item = char> {
2838        iter::repeat(self.char()).take(self.len as usize)
2839    }
2840
2841    pub fn char(&self) -> char {
2842        match self.kind {
2843            IndentKind::Space => ' ',
2844            IndentKind::Tab => '\t',
2845        }
2846    }
2847
2848    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
2849        match direction {
2850            Ordering::Less => {
2851                if self.kind == size.kind && self.len >= size.len {
2852                    self.len -= size.len;
2853                }
2854            }
2855            Ordering::Equal => {}
2856            Ordering::Greater => {
2857                if self.len == 0 {
2858                    self = size;
2859                } else if self.kind == size.kind {
2860                    self.len += size.len;
2861                }
2862            }
2863        }
2864        self
2865    }
2866}
2867
2868impl Completion {
2869    pub fn sort_key(&self) -> (usize, &str) {
2870        let kind_key = match self.lsp_completion.kind {
2871            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2872            _ => 1,
2873        };
2874        (kind_key, &self.label.text[self.label.filter_range.clone()])
2875    }
2876
2877    pub fn is_snippet(&self) -> bool {
2878        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2879    }
2880}
2881
2882pub fn contiguous_ranges(
2883    values: impl Iterator<Item = u32>,
2884    max_len: usize,
2885) -> impl Iterator<Item = Range<u32>> {
2886    let mut values = values;
2887    let mut current_range: Option<Range<u32>> = None;
2888    std::iter::from_fn(move || loop {
2889        if let Some(value) = values.next() {
2890            if let Some(range) = &mut current_range {
2891                if value == range.end && range.len() < max_len {
2892                    range.end += 1;
2893                    continue;
2894                }
2895            }
2896
2897            let prev_range = current_range.clone();
2898            current_range = Some(value..(value + 1));
2899            if prev_range.is_some() {
2900                return prev_range;
2901            }
2902        } else {
2903            return current_range.take();
2904        }
2905    })
2906}
2907
2908pub fn char_kind(c: char) -> CharKind {
2909    if c.is_whitespace() {
2910        CharKind::Whitespace
2911    } else if c.is_alphanumeric() || c == '_' {
2912        CharKind::Word
2913    } else {
2914        CharKind::Punctuation
2915    }
2916}
2917
2918/// Find all of the ranges of whitespace that occur at the ends of lines
2919/// in the given rope.
2920///
2921/// This could also be done with a regex search, but this implementation
2922/// avoids copying text.
2923pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
2924    let mut ranges = Vec::new();
2925
2926    let mut offset = 0;
2927    let mut prev_chunk_trailing_whitespace_range = 0..0;
2928    for chunk in rope.chunks() {
2929        let mut prev_line_trailing_whitespace_range = 0..0;
2930        for (i, line) in chunk.split('\n').enumerate() {
2931            let line_end_offset = offset + line.len();
2932            let trimmed_line_len = line.trim_end_matches(|c| matches!(c, ' ' | '\t')).len();
2933            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
2934
2935            if i == 0 && trimmed_line_len == 0 {
2936                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
2937            }
2938            if !prev_line_trailing_whitespace_range.is_empty() {
2939                ranges.push(prev_line_trailing_whitespace_range);
2940            }
2941
2942            offset = line_end_offset + 1;
2943            prev_line_trailing_whitespace_range = trailing_whitespace_range;
2944        }
2945
2946        offset -= 1;
2947        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
2948    }
2949
2950    if !prev_chunk_trailing_whitespace_range.is_empty() {
2951        ranges.push(prev_chunk_trailing_whitespace_range);
2952    }
2953
2954    ranges
2955}