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