buffer.rs

   1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, BracketPair, Grammar, Language, LanguageConfig, LanguageRegistry, PLAIN_TEXT,
   5};
   6use crate::{
   7    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   8    language_settings::{language_settings, LanguageSettings},
   9    outline::OutlineItem,
  10    syntax_map::{
  11        SyntaxLayerInfo, SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxSnapshot,
  12        ToTreeSitterPoint,
  13    },
  14    CodeLabel, LanguageScope, Outline,
  15};
  16use anyhow::{anyhow, Result};
  17pub use clock::ReplicaId;
  18use fs::LineEnding;
  19use futures::FutureExt as _;
  20use gpui::{fonts::HighlightStyle, AppContext, Entity, ModelContext, Task};
  21use lsp::LanguageServerId;
  22use parking_lot::Mutex;
  23use similar::{ChangeTag, TextDiff};
  24use smallvec::SmallVec;
  25use smol::future::yield_now;
  26use std::{
  27    any::Any,
  28    cmp::{self, Ordering},
  29    collections::BTreeMap,
  30    ffi::OsStr,
  31    future::Future,
  32    iter::{self, Iterator, Peekable},
  33    mem,
  34    ops::{Deref, Range},
  35    path::{Path, PathBuf},
  36    str,
  37    sync::Arc,
  38    time::{Duration, Instant, SystemTime, UNIX_EPOCH},
  39    vec,
  40};
  41use sum_tree::TreeMap;
  42use text::operation_queue::OperationQueue;
  43pub use text::{Buffer as TextBuffer, BufferSnapshot as TextBufferSnapshot, *};
  44use theme::SyntaxTheme;
  45#[cfg(any(test, feature = "test-support"))]
  46use util::RandomCharIter;
  47use util::{RangeExt, TryFutureExt as _};
  48
  49#[cfg(any(test, feature = "test-support"))]
  50pub use {tree_sitter_rust, tree_sitter_typescript};
  51
  52pub use lsp::DiagnosticSeverity;
  53
  54pub struct Buffer {
  55    text: TextBuffer,
  56    diff_base: Option<String>,
  57    git_diff: git::diff::BufferDiff,
  58    file: Option<Arc<dyn File>>,
  59    saved_version: clock::Global,
  60    saved_version_fingerprint: RopeFingerprint,
  61    saved_mtime: SystemTime,
  62    transaction_depth: usize,
  63    was_dirty_before_starting_transaction: Option<bool>,
  64    language: Option<Arc<Language>>,
  65    autoindent_requests: Vec<Arc<AutoindentRequest>>,
  66    pending_autoindent: Option<Task<()>>,
  67    sync_parse_timeout: Duration,
  68    syntax_map: Mutex<SyntaxMap>,
  69    parsing_in_background: bool,
  70    parse_count: usize,
  71    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
  72    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  73    selections_update_count: usize,
  74    diagnostics_update_count: usize,
  75    diagnostics_timestamp: clock::Lamport,
  76    file_update_count: usize,
  77    git_diff_update_count: usize,
  78    completion_triggers: Vec<String>,
  79    completion_triggers_timestamp: clock::Lamport,
  80    deferred_ops: OperationQueue<Operation>,
  81}
  82
  83pub struct BufferSnapshot {
  84    text: text::BufferSnapshot,
  85    pub git_diff: git::diff::BufferDiff,
  86    pub(crate) syntax: SyntaxSnapshot,
  87    file: Option<Arc<dyn File>>,
  88    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
  89    diagnostics_update_count: usize,
  90    file_update_count: usize,
  91    git_diff_update_count: usize,
  92    remote_selections: TreeMap<ReplicaId, SelectionSet>,
  93    selections_update_count: usize,
  94    language: Option<Arc<Language>>,
  95    parse_count: usize,
  96}
  97
  98#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
  99pub struct IndentSize {
 100    pub len: u32,
 101    pub kind: IndentKind,
 102}
 103
 104#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
 105pub enum IndentKind {
 106    #[default]
 107    Space,
 108    Tab,
 109}
 110
 111#[derive(Copy, Clone, PartialEq, Eq, Debug, Default)]
 112pub enum CursorShape {
 113    #[default]
 114    Bar,
 115    Block,
 116    Underscore,
 117    Hollow,
 118}
 119
 120#[derive(Clone, Debug)]
 121struct SelectionSet {
 122    line_mode: bool,
 123    cursor_shape: CursorShape,
 124    selections: Arc<[Selection<Anchor>]>,
 125    lamport_timestamp: clock::Lamport,
 126}
 127
 128#[derive(Clone, Debug, PartialEq, Eq)]
 129pub struct GroupId {
 130    source: Arc<str>,
 131    id: usize,
 132}
 133
 134#[derive(Clone, Debug, PartialEq, Eq)]
 135pub struct Diagnostic {
 136    pub source: Option<String>,
 137    pub code: Option<String>,
 138    pub severity: DiagnosticSeverity,
 139    pub message: String,
 140    pub group_id: usize,
 141    pub is_valid: bool,
 142    pub is_primary: bool,
 143    pub is_disk_based: bool,
 144    pub is_unnecessary: bool,
 145}
 146
 147#[derive(Clone, Debug)]
 148pub struct Completion {
 149    pub old_range: Range<Anchor>,
 150    pub new_text: String,
 151    pub label: CodeLabel,
 152    pub lsp_completion: lsp::CompletionItem,
 153}
 154
 155#[derive(Clone, Debug)]
 156pub struct CodeAction {
 157    pub server_id: LanguageServerId,
 158    pub range: Range<Anchor>,
 159    pub lsp_action: lsp::CodeAction,
 160}
 161
 162#[derive(Clone, Debug, PartialEq, Eq)]
 163pub enum Operation {
 164    Buffer(text::Operation),
 165
 166    UpdateDiagnostics {
 167        server_id: LanguageServerId,
 168        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 169        lamport_timestamp: clock::Lamport,
 170    },
 171
 172    UpdateSelections {
 173        selections: Arc<[Selection<Anchor>]>,
 174        lamport_timestamp: clock::Lamport,
 175        line_mode: bool,
 176        cursor_shape: CursorShape,
 177    },
 178
 179    UpdateCompletionTriggers {
 180        triggers: Vec<String>,
 181        lamport_timestamp: clock::Lamport,
 182    },
 183}
 184
 185#[derive(Clone, Debug, PartialEq, Eq)]
 186pub enum Event {
 187    Operation(Operation),
 188    Edited,
 189    DirtyChanged,
 190    Saved,
 191    FileHandleChanged,
 192    Reloaded,
 193    DiffBaseChanged,
 194    LanguageChanged,
 195    Reparsed,
 196    DiagnosticsUpdated,
 197    Closed,
 198}
 199
 200pub trait File: Send + Sync {
 201    fn as_local(&self) -> Option<&dyn LocalFile>;
 202
 203    fn is_local(&self) -> bool {
 204        self.as_local().is_some()
 205    }
 206
 207    fn mtime(&self) -> SystemTime;
 208
 209    /// Returns the path of this file relative to the worktree's root directory.
 210    fn path(&self) -> &Arc<Path>;
 211
 212    /// Returns the path of this file relative to the worktree's parent directory (this means it
 213    /// includes the name of the worktree's root folder).
 214    fn full_path(&self, cx: &AppContext) -> PathBuf;
 215
 216    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 217    /// of its worktree, then this method will return the name of the worktree itself.
 218    fn file_name<'a>(&'a self, cx: &'a AppContext) -> &'a OsStr;
 219
 220    /// Returns the id of the worktree to which this file belongs.
 221    ///
 222    /// This is needed for looking up project-specific settings.
 223    fn worktree_id(&self) -> usize;
 224
 225    fn is_deleted(&self) -> bool;
 226
 227    fn as_any(&self) -> &dyn Any;
 228
 229    fn to_proto(&self) -> rpc::proto::File;
 230}
 231
 232pub trait LocalFile: File {
 233    /// Returns the absolute path of this file.
 234    fn abs_path(&self, cx: &AppContext) -> PathBuf;
 235
 236    fn load(&self, cx: &AppContext) -> Task<Result<String>>;
 237
 238    fn buffer_reloaded(
 239        &self,
 240        buffer_id: u64,
 241        version: &clock::Global,
 242        fingerprint: RopeFingerprint,
 243        line_ending: LineEnding,
 244        mtime: SystemTime,
 245        cx: &mut AppContext,
 246    );
 247}
 248
 249#[derive(Clone, Debug)]
 250pub enum AutoindentMode {
 251    /// Indent each line of inserted text.
 252    EachLine,
 253    /// Apply the same indentation adjustment to all of the lines
 254    /// in a given insertion.
 255    Block {
 256        /// The original indentation level of the first line of each
 257        /// insertion, if it has been copied.
 258        original_indent_columns: Vec<u32>,
 259    },
 260}
 261
 262#[derive(Clone)]
 263struct AutoindentRequest {
 264    before_edit: BufferSnapshot,
 265    entries: Vec<AutoindentRequestEntry>,
 266    is_block_mode: bool,
 267}
 268
 269#[derive(Clone)]
 270struct AutoindentRequestEntry {
 271    /// A range of the buffer whose indentation should be adjusted.
 272    range: Range<Anchor>,
 273    /// Whether or not these lines should be considered brand new, for the
 274    /// purpose of auto-indent. When text is not new, its indentation will
 275    /// only be adjusted if the suggested indentation level has *changed*
 276    /// since the edit was made.
 277    first_line_is_new: bool,
 278    indent_size: IndentSize,
 279    original_indent_column: Option<u32>,
 280}
 281
 282#[derive(Debug)]
 283struct IndentSuggestion {
 284    basis_row: u32,
 285    delta: Ordering,
 286    within_error: bool,
 287}
 288
 289struct BufferChunkHighlights<'a> {
 290    captures: SyntaxMapCaptures<'a>,
 291    next_capture: Option<SyntaxMapCapture<'a>>,
 292    stack: Vec<(usize, HighlightId)>,
 293    highlight_maps: Vec<HighlightMap>,
 294}
 295
 296pub struct BufferChunks<'a> {
 297    range: Range<usize>,
 298    chunks: text::Chunks<'a>,
 299    diagnostic_endpoints: Peekable<vec::IntoIter<DiagnosticEndpoint>>,
 300    error_depth: usize,
 301    warning_depth: usize,
 302    information_depth: usize,
 303    hint_depth: usize,
 304    unnecessary_depth: usize,
 305    highlights: Option<BufferChunkHighlights<'a>>,
 306}
 307
 308#[derive(Clone, Copy, Debug, Default)]
 309pub struct Chunk<'a> {
 310    pub text: &'a str,
 311    pub syntax_highlight_id: Option<HighlightId>,
 312    pub highlight_style: Option<HighlightStyle>,
 313    pub diagnostic_severity: Option<DiagnosticSeverity>,
 314    pub is_unnecessary: bool,
 315    pub is_tab: bool,
 316}
 317
 318pub struct Diff {
 319    pub(crate) base_version: clock::Global,
 320    line_ending: LineEnding,
 321    edits: Vec<(Range<usize>, Arc<str>)>,
 322}
 323
 324#[derive(Clone, Copy)]
 325pub(crate) struct DiagnosticEndpoint {
 326    offset: usize,
 327    is_start: bool,
 328    severity: DiagnosticSeverity,
 329    is_unnecessary: bool,
 330}
 331
 332#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 333pub enum CharKind {
 334    Punctuation,
 335    Whitespace,
 336    Word,
 337}
 338
 339impl CharKind {
 340    pub fn coerce_punctuation(self, treat_punctuation_as_word: bool) -> Self {
 341        if treat_punctuation_as_word && self == CharKind::Punctuation {
 342            CharKind::Word
 343        } else {
 344            self
 345        }
 346    }
 347}
 348
 349impl Buffer {
 350    pub fn new<T: Into<String>>(replica_id: ReplicaId, id: u64, base_text: T) -> Self {
 351        Self::build(
 352            TextBuffer::new(replica_id, id, base_text.into()),
 353            None,
 354            None,
 355        )
 356    }
 357
 358    pub fn remote(remote_id: u64, replica_id: ReplicaId, base_text: String) -> Self {
 359        Self::build(
 360            TextBuffer::new(replica_id, remote_id, base_text),
 361            None,
 362            None,
 363        )
 364    }
 365
 366    pub fn from_proto(
 367        replica_id: ReplicaId,
 368        message: proto::BufferState,
 369        file: Option<Arc<dyn File>>,
 370    ) -> Result<Self> {
 371        let buffer = TextBuffer::new(replica_id, message.id, message.base_text);
 372        let mut this = Self::build(
 373            buffer,
 374            message.diff_base.map(|text| text.into_boxed_str().into()),
 375            file,
 376        );
 377        this.text.set_line_ending(proto::deserialize_line_ending(
 378            rpc::proto::LineEnding::from_i32(message.line_ending)
 379                .ok_or_else(|| anyhow!("missing line_ending"))?,
 380        ));
 381        this.saved_version = proto::deserialize_version(&message.saved_version);
 382        this.saved_version_fingerprint =
 383            proto::deserialize_fingerprint(&message.saved_version_fingerprint)?;
 384        this.saved_mtime = message
 385            .saved_mtime
 386            .ok_or_else(|| anyhow!("invalid saved_mtime"))?
 387            .into();
 388        Ok(this)
 389    }
 390
 391    pub fn to_proto(&self) -> proto::BufferState {
 392        proto::BufferState {
 393            id: self.remote_id(),
 394            file: self.file.as_ref().map(|f| f.to_proto()),
 395            base_text: self.base_text().to_string(),
 396            diff_base: self.diff_base.as_ref().map(|h| h.to_string()),
 397            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 398            saved_version: proto::serialize_version(&self.saved_version),
 399            saved_version_fingerprint: proto::serialize_fingerprint(self.saved_version_fingerprint),
 400            saved_mtime: Some(self.saved_mtime.into()),
 401        }
 402    }
 403
 404    pub fn serialize_ops(
 405        &self,
 406        since: Option<clock::Global>,
 407        cx: &AppContext,
 408    ) -> Task<Vec<proto::Operation>> {
 409        let mut operations = Vec::new();
 410        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 411
 412        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 413            proto::serialize_operation(&Operation::UpdateSelections {
 414                selections: set.selections.clone(),
 415                lamport_timestamp: set.lamport_timestamp,
 416                line_mode: set.line_mode,
 417                cursor_shape: set.cursor_shape,
 418            })
 419        }));
 420
 421        for (server_id, diagnostics) in &self.diagnostics {
 422            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 423                lamport_timestamp: self.diagnostics_timestamp,
 424                server_id: *server_id,
 425                diagnostics: diagnostics.iter().cloned().collect(),
 426            }));
 427        }
 428
 429        operations.push(proto::serialize_operation(
 430            &Operation::UpdateCompletionTriggers {
 431                triggers: self.completion_triggers.clone(),
 432                lamport_timestamp: self.completion_triggers_timestamp,
 433            },
 434        ));
 435
 436        let text_operations = self.text.operations().clone();
 437        cx.background().spawn(async move {
 438            let since = since.unwrap_or_default();
 439            operations.extend(
 440                text_operations
 441                    .iter()
 442                    .filter(|(_, op)| !since.observed(op.local_timestamp()))
 443                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 444            );
 445            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 446            operations
 447        })
 448    }
 449
 450    pub fn with_language(mut self, language: Arc<Language>, cx: &mut ModelContext<Self>) -> Self {
 451        self.set_language(Some(language), cx);
 452        self
 453    }
 454
 455    pub fn build(
 456        buffer: TextBuffer,
 457        diff_base: Option<String>,
 458        file: Option<Arc<dyn File>>,
 459    ) -> Self {
 460        let saved_mtime = if let Some(file) = file.as_ref() {
 461            file.mtime()
 462        } else {
 463            UNIX_EPOCH
 464        };
 465
 466        Self {
 467            saved_mtime,
 468            saved_version: buffer.version(),
 469            saved_version_fingerprint: buffer.as_rope().fingerprint(),
 470            transaction_depth: 0,
 471            was_dirty_before_starting_transaction: None,
 472            text: buffer,
 473            diff_base,
 474            git_diff: git::diff::BufferDiff::new(),
 475            file,
 476            syntax_map: Mutex::new(SyntaxMap::new()),
 477            parsing_in_background: false,
 478            parse_count: 0,
 479            sync_parse_timeout: Duration::from_millis(1),
 480            autoindent_requests: Default::default(),
 481            pending_autoindent: Default::default(),
 482            language: None,
 483            remote_selections: Default::default(),
 484            selections_update_count: 0,
 485            diagnostics: Default::default(),
 486            diagnostics_update_count: 0,
 487            diagnostics_timestamp: Default::default(),
 488            file_update_count: 0,
 489            git_diff_update_count: 0,
 490            completion_triggers: Default::default(),
 491            completion_triggers_timestamp: Default::default(),
 492            deferred_ops: OperationQueue::new(),
 493        }
 494    }
 495
 496    pub fn snapshot(&self) -> BufferSnapshot {
 497        let text = self.text.snapshot();
 498        let mut syntax_map = self.syntax_map.lock();
 499        syntax_map.interpolate(&text);
 500        let syntax = syntax_map.snapshot();
 501
 502        BufferSnapshot {
 503            text,
 504            syntax,
 505            git_diff: self.git_diff.clone(),
 506            file: self.file.clone(),
 507            remote_selections: self.remote_selections.clone(),
 508            diagnostics: self.diagnostics.clone(),
 509            diagnostics_update_count: self.diagnostics_update_count,
 510            file_update_count: self.file_update_count,
 511            git_diff_update_count: self.git_diff_update_count,
 512            language: self.language.clone(),
 513            parse_count: self.parse_count,
 514            selections_update_count: self.selections_update_count,
 515        }
 516    }
 517
 518    pub fn as_text_snapshot(&self) -> &text::BufferSnapshot {
 519        &self.text
 520    }
 521
 522    pub fn text_snapshot(&self) -> text::BufferSnapshot {
 523        self.text.snapshot()
 524    }
 525
 526    pub fn file(&self) -> Option<&Arc<dyn File>> {
 527        self.file.as_ref()
 528    }
 529
 530    pub fn saved_version(&self) -> &clock::Global {
 531        &self.saved_version
 532    }
 533
 534    pub fn saved_version_fingerprint(&self) -> RopeFingerprint {
 535        self.saved_version_fingerprint
 536    }
 537
 538    pub fn saved_mtime(&self) -> SystemTime {
 539        self.saved_mtime
 540    }
 541
 542    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut ModelContext<Self>) {
 543        self.syntax_map.lock().clear();
 544        self.language = language;
 545        self.reparse(cx);
 546        cx.emit(Event::LanguageChanged);
 547    }
 548
 549    pub fn set_language_registry(&mut self, language_registry: Arc<LanguageRegistry>) {
 550        self.syntax_map
 551            .lock()
 552            .set_language_registry(language_registry);
 553    }
 554
 555    pub fn did_save(
 556        &mut self,
 557        version: clock::Global,
 558        fingerprint: RopeFingerprint,
 559        mtime: SystemTime,
 560        cx: &mut ModelContext<Self>,
 561    ) {
 562        self.saved_version = version;
 563        self.saved_version_fingerprint = fingerprint;
 564        self.saved_mtime = mtime;
 565        cx.emit(Event::Saved);
 566        cx.notify();
 567    }
 568
 569    pub fn reload(&mut self, cx: &mut ModelContext<Self>) -> Task<Result<Option<Transaction>>> {
 570        cx.spawn(|this, mut cx| async move {
 571            if let Some((new_mtime, new_text)) = this.read_with(&cx, |this, cx| {
 572                let file = this.file.as_ref()?.as_local()?;
 573                Some((file.mtime(), file.load(cx)))
 574            }) {
 575                let new_text = new_text.await?;
 576                let diff = this
 577                    .read_with(&cx, |this, cx| this.diff(new_text, cx))
 578                    .await;
 579                this.update(&mut cx, |this, cx| {
 580                    if this.version() == diff.base_version {
 581                        this.finalize_last_transaction();
 582                        this.apply_diff(diff, cx);
 583                        if let Some(transaction) = this.finalize_last_transaction().cloned() {
 584                            this.did_reload(
 585                                this.version(),
 586                                this.as_rope().fingerprint(),
 587                                this.line_ending(),
 588                                new_mtime,
 589                                cx,
 590                            );
 591                            return Ok(Some(transaction));
 592                        }
 593                    }
 594                    Ok(None)
 595                })
 596            } else {
 597                Ok(None)
 598            }
 599        })
 600    }
 601
 602    pub fn did_reload(
 603        &mut self,
 604        version: clock::Global,
 605        fingerprint: RopeFingerprint,
 606        line_ending: LineEnding,
 607        mtime: SystemTime,
 608        cx: &mut ModelContext<Self>,
 609    ) {
 610        self.saved_version = version;
 611        self.saved_version_fingerprint = fingerprint;
 612        self.text.set_line_ending(line_ending);
 613        self.saved_mtime = mtime;
 614        if let Some(file) = self.file.as_ref().and_then(|f| f.as_local()) {
 615            file.buffer_reloaded(
 616                self.remote_id(),
 617                &self.saved_version,
 618                self.saved_version_fingerprint,
 619                self.line_ending(),
 620                self.saved_mtime,
 621                cx,
 622            );
 623        }
 624        cx.emit(Event::Reloaded);
 625        cx.notify();
 626    }
 627
 628    pub fn file_updated(
 629        &mut self,
 630        new_file: Arc<dyn File>,
 631        cx: &mut ModelContext<Self>,
 632    ) -> Task<()> {
 633        let mut file_changed = false;
 634        let mut task = Task::ready(());
 635
 636        if let Some(old_file) = self.file.as_ref() {
 637            if new_file.path() != old_file.path() {
 638                file_changed = true;
 639            }
 640
 641            if new_file.is_deleted() {
 642                if !old_file.is_deleted() {
 643                    file_changed = true;
 644                    if !self.is_dirty() {
 645                        cx.emit(Event::DirtyChanged);
 646                    }
 647                }
 648            } else {
 649                let new_mtime = new_file.mtime();
 650                if new_mtime != old_file.mtime() {
 651                    file_changed = true;
 652
 653                    if !self.is_dirty() {
 654                        let reload = self.reload(cx).log_err().map(drop);
 655                        task = cx.foreground().spawn(reload);
 656                    }
 657                }
 658            }
 659        } else {
 660            file_changed = true;
 661        };
 662
 663        if file_changed {
 664            self.file_update_count += 1;
 665            cx.emit(Event::FileHandleChanged);
 666            cx.notify();
 667        }
 668        self.file = Some(new_file);
 669        task
 670    }
 671
 672    pub fn diff_base(&self) -> Option<&str> {
 673        self.diff_base.as_deref()
 674    }
 675
 676    pub fn set_diff_base(&mut self, diff_base: Option<String>, cx: &mut ModelContext<Self>) {
 677        self.diff_base = diff_base;
 678        self.git_diff_recalc(cx);
 679        cx.emit(Event::DiffBaseChanged);
 680    }
 681
 682    pub fn git_diff_recalc(&mut self, cx: &mut ModelContext<Self>) -> Option<Task<()>> {
 683        let diff_base = self.diff_base.clone()?; // TODO: Make this an Arc
 684        let snapshot = self.snapshot();
 685
 686        let mut diff = self.git_diff.clone();
 687        let diff = cx.background().spawn(async move {
 688            diff.update(&diff_base, &snapshot).await;
 689            diff
 690        });
 691
 692        let handle = cx.weak_handle();
 693        Some(cx.spawn_weak(|_, mut cx| async move {
 694            let buffer_diff = diff.await;
 695            if let Some(this) = handle.upgrade(&mut cx) {
 696                this.update(&mut cx, |this, _| {
 697                    this.git_diff = buffer_diff;
 698                    this.git_diff_update_count += 1;
 699                })
 700            }
 701        }))
 702    }
 703
 704    pub fn close(&mut self, cx: &mut ModelContext<Self>) {
 705        cx.emit(Event::Closed);
 706    }
 707
 708    pub fn language(&self) -> Option<&Arc<Language>> {
 709        self.language.as_ref()
 710    }
 711
 712    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
 713        let offset = position.to_offset(self);
 714        self.syntax_map
 715            .lock()
 716            .layers_for_range(offset..offset, &self.text)
 717            .last()
 718            .map(|info| info.language.clone())
 719            .or_else(|| self.language.clone())
 720    }
 721
 722    pub fn parse_count(&self) -> usize {
 723        self.parse_count
 724    }
 725
 726    pub fn selections_update_count(&self) -> usize {
 727        self.selections_update_count
 728    }
 729
 730    pub fn diagnostics_update_count(&self) -> usize {
 731        self.diagnostics_update_count
 732    }
 733
 734    pub fn file_update_count(&self) -> usize {
 735        self.file_update_count
 736    }
 737
 738    pub fn git_diff_update_count(&self) -> usize {
 739        self.git_diff_update_count
 740    }
 741
 742    #[cfg(any(test, feature = "test-support"))]
 743    pub fn is_parsing(&self) -> bool {
 744        self.parsing_in_background
 745    }
 746
 747    pub fn contains_unknown_injections(&self) -> bool {
 748        self.syntax_map.lock().contains_unknown_injections()
 749    }
 750
 751    #[cfg(test)]
 752    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
 753        self.sync_parse_timeout = timeout;
 754    }
 755
 756    /// Called after an edit to synchronize the buffer's main parse tree with
 757    /// the buffer's new underlying state.
 758    ///
 759    /// Locks the syntax map and interpolates the edits since the last reparse
 760    /// into the foreground syntax tree.
 761    ///
 762    /// Then takes a stable snapshot of the syntax map before unlocking it.
 763    /// The snapshot with the interpolated edits is sent to a background thread,
 764    /// where we ask Tree-sitter to perform an incremental parse.
 765    ///
 766    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
 767    /// waiting on the parse to complete. As soon as it completes, we proceed
 768    /// synchronously, unless a 1ms timeout elapses.
 769    ///
 770    /// If we time out waiting on the parse, we spawn a second task waiting
 771    /// until the parse does complete and return with the interpolated tree still
 772    /// in the foreground. When the background parse completes, call back into
 773    /// the main thread and assign the foreground parse state.
 774    ///
 775    /// If the buffer or grammar changed since the start of the background parse,
 776    /// initiate an additional reparse recursively. To avoid concurrent parses
 777    /// for the same buffer, we only initiate a new parse if we are not already
 778    /// parsing in the background.
 779    pub fn reparse(&mut self, cx: &mut ModelContext<Self>) {
 780        if self.parsing_in_background {
 781            return;
 782        }
 783        let language = if let Some(language) = self.language.clone() {
 784            language
 785        } else {
 786            return;
 787        };
 788
 789        let text = self.text_snapshot();
 790        let parsed_version = self.version();
 791
 792        let mut syntax_map = self.syntax_map.lock();
 793        syntax_map.interpolate(&text);
 794        let language_registry = syntax_map.language_registry();
 795        let mut syntax_snapshot = syntax_map.snapshot();
 796        drop(syntax_map);
 797
 798        let parse_task = cx.background().spawn({
 799            let language = language.clone();
 800            let language_registry = language_registry.clone();
 801            async move {
 802                syntax_snapshot.reparse(&text, language_registry, language);
 803                syntax_snapshot
 804            }
 805        });
 806
 807        match cx
 808            .background()
 809            .block_with_timeout(self.sync_parse_timeout, parse_task)
 810        {
 811            Ok(new_syntax_snapshot) => {
 812                self.did_finish_parsing(new_syntax_snapshot, cx);
 813                return;
 814            }
 815            Err(parse_task) => {
 816                self.parsing_in_background = true;
 817                cx.spawn(move |this, mut cx| async move {
 818                    let new_syntax_map = parse_task.await;
 819                    this.update(&mut cx, move |this, cx| {
 820                        let grammar_changed =
 821                            this.language.as_ref().map_or(true, |current_language| {
 822                                !Arc::ptr_eq(&language, current_language)
 823                            });
 824                        let language_registry_changed = new_syntax_map
 825                            .contains_unknown_injections()
 826                            && language_registry.map_or(false, |registry| {
 827                                registry.version() != new_syntax_map.language_registry_version()
 828                            });
 829                        let parse_again = language_registry_changed
 830                            || grammar_changed
 831                            || this.version.changed_since(&parsed_version);
 832                        this.did_finish_parsing(new_syntax_map, cx);
 833                        this.parsing_in_background = false;
 834                        if parse_again {
 835                            this.reparse(cx);
 836                        }
 837                    });
 838                })
 839                .detach();
 840            }
 841        }
 842    }
 843
 844    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut ModelContext<Self>) {
 845        self.parse_count += 1;
 846        self.syntax_map.lock().did_parse(syntax_snapshot);
 847        self.request_autoindent(cx);
 848        cx.emit(Event::Reparsed);
 849        cx.notify();
 850    }
 851
 852    pub fn update_diagnostics(
 853        &mut self,
 854        server_id: LanguageServerId,
 855        diagnostics: DiagnosticSet,
 856        cx: &mut ModelContext<Self>,
 857    ) {
 858        let lamport_timestamp = self.text.lamport_clock.tick();
 859        let op = Operation::UpdateDiagnostics {
 860            server_id,
 861            diagnostics: diagnostics.iter().cloned().collect(),
 862            lamport_timestamp,
 863        };
 864        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
 865        self.send_operation(op, cx);
 866    }
 867
 868    fn request_autoindent(&mut self, cx: &mut ModelContext<Self>) {
 869        if let Some(indent_sizes) = self.compute_autoindents() {
 870            let indent_sizes = cx.background().spawn(indent_sizes);
 871            match cx
 872                .background()
 873                .block_with_timeout(Duration::from_micros(500), indent_sizes)
 874            {
 875                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
 876                Err(indent_sizes) => {
 877                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
 878                        let indent_sizes = indent_sizes.await;
 879                        this.update(&mut cx, |this, cx| {
 880                            this.apply_autoindents(indent_sizes, cx);
 881                        });
 882                    }));
 883                }
 884            }
 885        } else {
 886            self.autoindent_requests.clear();
 887        }
 888    }
 889
 890    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
 891        let max_rows_between_yields = 100;
 892        let snapshot = self.snapshot();
 893        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
 894            return None;
 895        }
 896
 897        let autoindent_requests = self.autoindent_requests.clone();
 898        Some(async move {
 899            let mut indent_sizes = BTreeMap::new();
 900            for request in autoindent_requests {
 901                // Resolve each edited range to its row in the current buffer and in the
 902                // buffer before this batch of edits.
 903                let mut row_ranges = Vec::new();
 904                let mut old_to_new_rows = BTreeMap::new();
 905                let mut language_indent_sizes_by_new_row = Vec::new();
 906                for entry in &request.entries {
 907                    let position = entry.range.start;
 908                    let new_row = position.to_point(&snapshot).row;
 909                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
 910                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
 911
 912                    if !entry.first_line_is_new {
 913                        let old_row = position.to_point(&request.before_edit).row;
 914                        old_to_new_rows.insert(old_row, new_row);
 915                    }
 916                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
 917                }
 918
 919                // Build a map containing the suggested indentation for each of the edited lines
 920                // with respect to the state of the buffer before these edits. This map is keyed
 921                // by the rows for these lines in the current state of the buffer.
 922                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
 923                let old_edited_ranges =
 924                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
 925                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 926                let mut language_indent_size = IndentSize::default();
 927                for old_edited_range in old_edited_ranges {
 928                    let suggestions = request
 929                        .before_edit
 930                        .suggest_autoindents(old_edited_range.clone())
 931                        .into_iter()
 932                        .flatten();
 933                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
 934                        if let Some(suggestion) = suggestion {
 935                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
 936
 937                            // Find the indent size based on the language for this row.
 938                            while let Some((row, size)) = language_indent_sizes.peek() {
 939                                if *row > new_row {
 940                                    break;
 941                                }
 942                                language_indent_size = *size;
 943                                language_indent_sizes.next();
 944                            }
 945
 946                            let suggested_indent = old_to_new_rows
 947                                .get(&suggestion.basis_row)
 948                                .and_then(|from_row| {
 949                                    Some(old_suggestions.get(from_row).copied()?.0)
 950                                })
 951                                .unwrap_or_else(|| {
 952                                    request
 953                                        .before_edit
 954                                        .indent_size_for_line(suggestion.basis_row)
 955                                })
 956                                .with_delta(suggestion.delta, language_indent_size);
 957                            old_suggestions
 958                                .insert(new_row, (suggested_indent, suggestion.within_error));
 959                        }
 960                    }
 961                    yield_now().await;
 962                }
 963
 964                // In block mode, only compute indentation suggestions for the first line
 965                // of each insertion. Otherwise, compute suggestions for every inserted line.
 966                let new_edited_row_ranges = contiguous_ranges(
 967                    row_ranges.iter().flat_map(|(range, _)| {
 968                        if request.is_block_mode {
 969                            range.start..range.start + 1
 970                        } else {
 971                            range.clone()
 972                        }
 973                    }),
 974                    max_rows_between_yields,
 975                );
 976
 977                // Compute new suggestions for each line, but only include them in the result
 978                // if they differ from the old suggestion for that line.
 979                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
 980                let mut language_indent_size = IndentSize::default();
 981                for new_edited_row_range in new_edited_row_ranges {
 982                    let suggestions = snapshot
 983                        .suggest_autoindents(new_edited_row_range.clone())
 984                        .into_iter()
 985                        .flatten();
 986                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
 987                        if let Some(suggestion) = suggestion {
 988                            // Find the indent size based on the language for this row.
 989                            while let Some((row, size)) = language_indent_sizes.peek() {
 990                                if *row > new_row {
 991                                    break;
 992                                }
 993                                language_indent_size = *size;
 994                                language_indent_sizes.next();
 995                            }
 996
 997                            let suggested_indent = indent_sizes
 998                                .get(&suggestion.basis_row)
 999                                .copied()
1000                                .unwrap_or_else(|| {
1001                                    snapshot.indent_size_for_line(suggestion.basis_row)
1002                                })
1003                                .with_delta(suggestion.delta, language_indent_size);
1004                            if old_suggestions.get(&new_row).map_or(
1005                                true,
1006                                |(old_indentation, was_within_error)| {
1007                                    suggested_indent != *old_indentation
1008                                        && (!suggestion.within_error || *was_within_error)
1009                                },
1010                            ) {
1011                                indent_sizes.insert(new_row, suggested_indent);
1012                            }
1013                        }
1014                    }
1015                    yield_now().await;
1016                }
1017
1018                // For each block of inserted text, adjust the indentation of the remaining
1019                // lines of the block by the same amount as the first line was adjusted.
1020                if request.is_block_mode {
1021                    for (row_range, original_indent_column) in
1022                        row_ranges
1023                            .into_iter()
1024                            .filter_map(|(range, original_indent_column)| {
1025                                if range.len() > 1 {
1026                                    Some((range, original_indent_column?))
1027                                } else {
1028                                    None
1029                                }
1030                            })
1031                    {
1032                        let new_indent = indent_sizes
1033                            .get(&row_range.start)
1034                            .copied()
1035                            .unwrap_or_else(|| snapshot.indent_size_for_line(row_range.start));
1036                        let delta = new_indent.len as i64 - original_indent_column as i64;
1037                        if delta != 0 {
1038                            for row in row_range.skip(1) {
1039                                indent_sizes.entry(row).or_insert_with(|| {
1040                                    let mut size = snapshot.indent_size_for_line(row);
1041                                    if size.kind == new_indent.kind {
1042                                        match delta.cmp(&0) {
1043                                            Ordering::Greater => size.len += delta as u32,
1044                                            Ordering::Less => {
1045                                                size.len = size.len.saturating_sub(-delta as u32)
1046                                            }
1047                                            Ordering::Equal => {}
1048                                        }
1049                                    }
1050                                    size
1051                                });
1052                            }
1053                        }
1054                    }
1055                }
1056            }
1057
1058            indent_sizes
1059        })
1060    }
1061
1062    fn apply_autoindents(
1063        &mut self,
1064        indent_sizes: BTreeMap<u32, IndentSize>,
1065        cx: &mut ModelContext<Self>,
1066    ) {
1067        self.autoindent_requests.clear();
1068
1069        let edits: Vec<_> = indent_sizes
1070            .into_iter()
1071            .filter_map(|(row, indent_size)| {
1072                let current_size = indent_size_for_line(self, row);
1073                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1074            })
1075            .collect();
1076
1077        self.edit(edits, None, cx);
1078    }
1079
1080    // Create a minimal edit that will cause the the given row to be indented
1081    // with the given size. After applying this edit, the length of the line
1082    // will always be at least `new_size.len`.
1083    pub fn edit_for_indent_size_adjustment(
1084        row: u32,
1085        current_size: IndentSize,
1086        new_size: IndentSize,
1087    ) -> Option<(Range<Point>, String)> {
1088        if new_size.kind != current_size.kind {
1089            Some((
1090                Point::new(row, 0)..Point::new(row, current_size.len),
1091                iter::repeat(new_size.char())
1092                    .take(new_size.len as usize)
1093                    .collect::<String>(),
1094            ))
1095        } else {
1096            match new_size.len.cmp(&current_size.len) {
1097                Ordering::Greater => {
1098                    let point = Point::new(row, 0);
1099                    Some((
1100                        point..point,
1101                        iter::repeat(new_size.char())
1102                            .take((new_size.len - current_size.len) as usize)
1103                            .collect::<String>(),
1104                    ))
1105                }
1106
1107                Ordering::Less => Some((
1108                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1109                    String::new(),
1110                )),
1111
1112                Ordering::Equal => None,
1113            }
1114        }
1115    }
1116
1117    pub fn diff(&self, mut new_text: String, cx: &AppContext) -> Task<Diff> {
1118        let old_text = self.as_rope().clone();
1119        let base_version = self.version();
1120        cx.background().spawn(async move {
1121            let old_text = old_text.to_string();
1122            let line_ending = LineEnding::detect(&new_text);
1123            LineEnding::normalize(&mut new_text);
1124            let diff = TextDiff::from_chars(old_text.as_str(), new_text.as_str());
1125            let mut edits = Vec::new();
1126            let mut offset = 0;
1127            let empty: Arc<str> = "".into();
1128            for change in diff.iter_all_changes() {
1129                let value = change.value();
1130                let end_offset = offset + value.len();
1131                match change.tag() {
1132                    ChangeTag::Equal => {
1133                        offset = end_offset;
1134                    }
1135                    ChangeTag::Delete => {
1136                        edits.push((offset..end_offset, empty.clone()));
1137                        offset = end_offset;
1138                    }
1139                    ChangeTag::Insert => {
1140                        edits.push((offset..offset, value.into()));
1141                    }
1142                }
1143            }
1144            Diff {
1145                base_version,
1146                line_ending,
1147                edits,
1148            }
1149        })
1150    }
1151
1152    /// Spawn a background task that searches the buffer for any whitespace
1153    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1154    pub fn remove_trailing_whitespace(&self, cx: &AppContext) -> Task<Diff> {
1155        let old_text = self.as_rope().clone();
1156        let line_ending = self.line_ending();
1157        let base_version = self.version();
1158        cx.background().spawn(async move {
1159            let ranges = trailing_whitespace_ranges(&old_text);
1160            let empty = Arc::<str>::from("");
1161            Diff {
1162                base_version,
1163                line_ending,
1164                edits: ranges
1165                    .into_iter()
1166                    .map(|range| (range, empty.clone()))
1167                    .collect(),
1168            }
1169        })
1170    }
1171
1172    /// Ensure that the buffer ends with a single newline character, and
1173    /// no other whitespace.
1174    pub fn ensure_final_newline(&mut self, cx: &mut ModelContext<Self>) {
1175        let len = self.len();
1176        let mut offset = len;
1177        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1178            let non_whitespace_len = chunk
1179                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1180                .len();
1181            offset -= chunk.len();
1182            offset += non_whitespace_len;
1183            if non_whitespace_len != 0 {
1184                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1185                    return;
1186                }
1187                break;
1188            }
1189        }
1190        self.edit([(offset..len, "\n")], None, cx);
1191    }
1192
1193    /// Apply a diff to the buffer. If the buffer has changed since the given diff was
1194    /// calculated, then adjust the diff to account for those changes, and discard any
1195    /// parts of the diff that conflict with those changes.
1196    pub fn apply_diff(&mut self, diff: Diff, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1197        // Check for any edits to the buffer that have occurred since this diff
1198        // was computed.
1199        let snapshot = self.snapshot();
1200        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1201        let mut delta = 0;
1202        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1203            while let Some(edit_since) = edits_since.peek() {
1204                // If the edit occurs after a diff hunk, then it does not
1205                // affect that hunk.
1206                if edit_since.old.start > range.end {
1207                    break;
1208                }
1209                // If the edit precedes the diff hunk, then adjust the hunk
1210                // to reflect the edit.
1211                else if edit_since.old.end < range.start {
1212                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1213                    edits_since.next();
1214                }
1215                // If the edit intersects a diff hunk, then discard that hunk.
1216                else {
1217                    return None;
1218                }
1219            }
1220
1221            let start = (range.start as i64 + delta) as usize;
1222            let end = (range.end as i64 + delta) as usize;
1223            Some((start..end, new_text))
1224        });
1225
1226        self.start_transaction();
1227        self.text.set_line_ending(diff.line_ending);
1228        self.edit(adjusted_edits, None, cx);
1229        self.end_transaction(cx)
1230    }
1231
1232    pub fn is_dirty(&self) -> bool {
1233        self.saved_version_fingerprint != self.as_rope().fingerprint()
1234            || self.file.as_ref().map_or(false, |file| file.is_deleted())
1235    }
1236
1237    pub fn has_conflict(&self) -> bool {
1238        self.saved_version_fingerprint != self.as_rope().fingerprint()
1239            && self
1240                .file
1241                .as_ref()
1242                .map_or(false, |file| file.mtime() > self.saved_mtime)
1243    }
1244
1245    pub fn subscribe(&mut self) -> Subscription {
1246        self.text.subscribe()
1247    }
1248
1249    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1250        self.start_transaction_at(Instant::now())
1251    }
1252
1253    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1254        self.transaction_depth += 1;
1255        if self.was_dirty_before_starting_transaction.is_none() {
1256            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1257        }
1258        self.text.start_transaction_at(now)
1259    }
1260
1261    pub fn end_transaction(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1262        self.end_transaction_at(Instant::now(), cx)
1263    }
1264
1265    pub fn end_transaction_at(
1266        &mut self,
1267        now: Instant,
1268        cx: &mut ModelContext<Self>,
1269    ) -> Option<TransactionId> {
1270        assert!(self.transaction_depth > 0);
1271        self.transaction_depth -= 1;
1272        let was_dirty = if self.transaction_depth == 0 {
1273            self.was_dirty_before_starting_transaction.take().unwrap()
1274        } else {
1275            false
1276        };
1277        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
1278            self.did_edit(&start_version, was_dirty, cx);
1279            Some(transaction_id)
1280        } else {
1281            None
1282        }
1283    }
1284
1285    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
1286        self.text.push_transaction(transaction, now);
1287    }
1288
1289    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
1290        self.text.finalize_last_transaction()
1291    }
1292
1293    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
1294        self.text.group_until_transaction(transaction_id);
1295    }
1296
1297    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
1298        self.text.forget_transaction(transaction_id);
1299    }
1300
1301    pub fn wait_for_edits(
1302        &mut self,
1303        edit_ids: impl IntoIterator<Item = clock::Local>,
1304    ) -> impl Future<Output = Result<()>> {
1305        self.text.wait_for_edits(edit_ids)
1306    }
1307
1308    pub fn wait_for_anchors(
1309        &mut self,
1310        anchors: impl IntoIterator<Item = Anchor>,
1311    ) -> impl 'static + Future<Output = Result<()>> {
1312        self.text.wait_for_anchors(anchors)
1313    }
1314
1315    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = Result<()>> {
1316        self.text.wait_for_version(version)
1317    }
1318
1319    pub fn give_up_waiting(&mut self) {
1320        self.text.give_up_waiting();
1321    }
1322
1323    pub fn set_active_selections(
1324        &mut self,
1325        selections: Arc<[Selection<Anchor>]>,
1326        line_mode: bool,
1327        cursor_shape: CursorShape,
1328        cx: &mut ModelContext<Self>,
1329    ) {
1330        let lamport_timestamp = self.text.lamport_clock.tick();
1331        self.remote_selections.insert(
1332            self.text.replica_id(),
1333            SelectionSet {
1334                selections: selections.clone(),
1335                lamport_timestamp,
1336                line_mode,
1337                cursor_shape,
1338            },
1339        );
1340        self.send_operation(
1341            Operation::UpdateSelections {
1342                selections,
1343                line_mode,
1344                lamport_timestamp,
1345                cursor_shape,
1346            },
1347            cx,
1348        );
1349    }
1350
1351    pub fn remove_active_selections(&mut self, cx: &mut ModelContext<Self>) {
1352        if self
1353            .remote_selections
1354            .get(&self.text.replica_id())
1355            .map_or(true, |set| !set.selections.is_empty())
1356        {
1357            self.set_active_selections(Arc::from([]), false, Default::default(), cx);
1358        }
1359    }
1360
1361    pub fn set_text<T>(&mut self, text: T, cx: &mut ModelContext<Self>) -> Option<clock::Local>
1362    where
1363        T: Into<Arc<str>>,
1364    {
1365        self.autoindent_requests.clear();
1366        self.edit([(0..self.len(), text)], None, cx)
1367    }
1368
1369    pub fn edit<I, S, T>(
1370        &mut self,
1371        edits_iter: I,
1372        autoindent_mode: Option<AutoindentMode>,
1373        cx: &mut ModelContext<Self>,
1374    ) -> Option<clock::Local>
1375    where
1376        I: IntoIterator<Item = (Range<S>, T)>,
1377        S: ToOffset,
1378        T: Into<Arc<str>>,
1379    {
1380        // Skip invalid edits and coalesce contiguous ones.
1381        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
1382        for (range, new_text) in edits_iter {
1383            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
1384            if range.start > range.end {
1385                mem::swap(&mut range.start, &mut range.end);
1386            }
1387            let new_text = new_text.into();
1388            if !new_text.is_empty() || !range.is_empty() {
1389                if let Some((prev_range, prev_text)) = edits.last_mut() {
1390                    if prev_range.end >= range.start {
1391                        prev_range.end = cmp::max(prev_range.end, range.end);
1392                        *prev_text = format!("{prev_text}{new_text}").into();
1393                    } else {
1394                        edits.push((range, new_text));
1395                    }
1396                } else {
1397                    edits.push((range, new_text));
1398                }
1399            }
1400        }
1401        if edits.is_empty() {
1402            return None;
1403        }
1404
1405        self.start_transaction();
1406        self.pending_autoindent.take();
1407        let autoindent_request = autoindent_mode
1408            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
1409
1410        let edit_operation = self.text.edit(edits.iter().cloned());
1411        let edit_id = edit_operation.local_timestamp();
1412
1413        if let Some((before_edit, mode)) = autoindent_request {
1414            let mut delta = 0isize;
1415            let entries = edits
1416                .into_iter()
1417                .enumerate()
1418                .zip(&edit_operation.as_edit().unwrap().new_text)
1419                .map(|((ix, (range, _)), new_text)| {
1420                    let new_text_length = new_text.len();
1421                    let old_start = range.start.to_point(&before_edit);
1422                    let new_start = (delta + range.start as isize) as usize;
1423                    delta += new_text_length as isize - (range.end as isize - range.start as isize);
1424
1425                    let mut range_of_insertion_to_indent = 0..new_text_length;
1426                    let mut first_line_is_new = false;
1427                    let mut original_indent_column = None;
1428
1429                    // When inserting an entire line at the beginning of an existing line,
1430                    // treat the insertion as new.
1431                    if new_text.contains('\n')
1432                        && old_start.column <= before_edit.indent_size_for_line(old_start.row).len
1433                    {
1434                        first_line_is_new = true;
1435                    }
1436
1437                    // When inserting text starting with a newline, avoid auto-indenting the
1438                    // previous line.
1439                    if new_text.starts_with('\n') {
1440                        range_of_insertion_to_indent.start += 1;
1441                        first_line_is_new = true;
1442                    }
1443
1444                    // Avoid auto-indenting after the insertion.
1445                    if let AutoindentMode::Block {
1446                        original_indent_columns,
1447                    } = &mode
1448                    {
1449                        original_indent_column =
1450                            Some(original_indent_columns.get(ix).copied().unwrap_or_else(|| {
1451                                indent_size_for_text(
1452                                    new_text[range_of_insertion_to_indent.clone()].chars(),
1453                                )
1454                                .len
1455                            }));
1456                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
1457                            range_of_insertion_to_indent.end -= 1;
1458                        }
1459                    }
1460
1461                    AutoindentRequestEntry {
1462                        first_line_is_new,
1463                        original_indent_column,
1464                        indent_size: before_edit.language_indent_size_at(range.start, cx),
1465                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
1466                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
1467                    }
1468                })
1469                .collect();
1470
1471            self.autoindent_requests.push(Arc::new(AutoindentRequest {
1472                before_edit,
1473                entries,
1474                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
1475            }));
1476        }
1477
1478        self.end_transaction(cx);
1479        self.send_operation(Operation::Buffer(edit_operation), cx);
1480        Some(edit_id)
1481    }
1482
1483    fn did_edit(
1484        &mut self,
1485        old_version: &clock::Global,
1486        was_dirty: bool,
1487        cx: &mut ModelContext<Self>,
1488    ) {
1489        if self.edits_since::<usize>(old_version).next().is_none() {
1490            return;
1491        }
1492
1493        self.reparse(cx);
1494
1495        cx.emit(Event::Edited);
1496        if was_dirty != self.is_dirty() {
1497            cx.emit(Event::DirtyChanged);
1498        }
1499        cx.notify();
1500    }
1501
1502    pub fn apply_ops<I: IntoIterator<Item = Operation>>(
1503        &mut self,
1504        ops: I,
1505        cx: &mut ModelContext<Self>,
1506    ) -> Result<()> {
1507        self.pending_autoindent.take();
1508        let was_dirty = self.is_dirty();
1509        let old_version = self.version.clone();
1510        let mut deferred_ops = Vec::new();
1511        let buffer_ops = ops
1512            .into_iter()
1513            .filter_map(|op| match op {
1514                Operation::Buffer(op) => Some(op),
1515                _ => {
1516                    if self.can_apply_op(&op) {
1517                        self.apply_op(op, cx);
1518                    } else {
1519                        deferred_ops.push(op);
1520                    }
1521                    None
1522                }
1523            })
1524            .collect::<Vec<_>>();
1525        self.text.apply_ops(buffer_ops)?;
1526        self.deferred_ops.insert(deferred_ops);
1527        self.flush_deferred_ops(cx);
1528        self.did_edit(&old_version, was_dirty, cx);
1529        // Notify independently of whether the buffer was edited as the operations could include a
1530        // selection update.
1531        cx.notify();
1532        Ok(())
1533    }
1534
1535    fn flush_deferred_ops(&mut self, cx: &mut ModelContext<Self>) {
1536        let mut deferred_ops = Vec::new();
1537        for op in self.deferred_ops.drain().iter().cloned() {
1538            if self.can_apply_op(&op) {
1539                self.apply_op(op, cx);
1540            } else {
1541                deferred_ops.push(op);
1542            }
1543        }
1544        self.deferred_ops.insert(deferred_ops);
1545    }
1546
1547    fn can_apply_op(&self, operation: &Operation) -> bool {
1548        match operation {
1549            Operation::Buffer(_) => {
1550                unreachable!("buffer operations should never be applied at this layer")
1551            }
1552            Operation::UpdateDiagnostics {
1553                diagnostics: diagnostic_set,
1554                ..
1555            } => diagnostic_set.iter().all(|diagnostic| {
1556                self.text.can_resolve(&diagnostic.range.start)
1557                    && self.text.can_resolve(&diagnostic.range.end)
1558            }),
1559            Operation::UpdateSelections { selections, .. } => selections
1560                .iter()
1561                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
1562            Operation::UpdateCompletionTriggers { .. } => true,
1563        }
1564    }
1565
1566    fn apply_op(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1567        match operation {
1568            Operation::Buffer(_) => {
1569                unreachable!("buffer operations should never be applied at this layer")
1570            }
1571            Operation::UpdateDiagnostics {
1572                server_id,
1573                diagnostics: diagnostic_set,
1574                lamport_timestamp,
1575            } => {
1576                let snapshot = self.snapshot();
1577                self.apply_diagnostic_update(
1578                    server_id,
1579                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
1580                    lamport_timestamp,
1581                    cx,
1582                );
1583            }
1584            Operation::UpdateSelections {
1585                selections,
1586                lamport_timestamp,
1587                line_mode,
1588                cursor_shape,
1589            } => {
1590                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
1591                    if set.lamport_timestamp > lamport_timestamp {
1592                        return;
1593                    }
1594                }
1595
1596                self.remote_selections.insert(
1597                    lamport_timestamp.replica_id,
1598                    SelectionSet {
1599                        selections,
1600                        lamport_timestamp,
1601                        line_mode,
1602                        cursor_shape,
1603                    },
1604                );
1605                self.text.lamport_clock.observe(lamport_timestamp);
1606                self.selections_update_count += 1;
1607            }
1608            Operation::UpdateCompletionTriggers {
1609                triggers,
1610                lamport_timestamp,
1611            } => {
1612                self.completion_triggers = triggers;
1613                self.text.lamport_clock.observe(lamport_timestamp);
1614            }
1615        }
1616    }
1617
1618    fn apply_diagnostic_update(
1619        &mut self,
1620        server_id: LanguageServerId,
1621        diagnostics: DiagnosticSet,
1622        lamport_timestamp: clock::Lamport,
1623        cx: &mut ModelContext<Self>,
1624    ) {
1625        if lamport_timestamp > self.diagnostics_timestamp {
1626            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
1627            if diagnostics.len() == 0 {
1628                if let Ok(ix) = ix {
1629                    self.diagnostics.remove(ix);
1630                }
1631            } else {
1632                match ix {
1633                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
1634                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
1635                };
1636            }
1637            self.diagnostics_timestamp = lamport_timestamp;
1638            self.diagnostics_update_count += 1;
1639            self.text.lamport_clock.observe(lamport_timestamp);
1640            cx.notify();
1641            cx.emit(Event::DiagnosticsUpdated);
1642        }
1643    }
1644
1645    fn send_operation(&mut self, operation: Operation, cx: &mut ModelContext<Self>) {
1646        cx.emit(Event::Operation(operation));
1647    }
1648
1649    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut ModelContext<Self>) {
1650        self.remote_selections.remove(&replica_id);
1651        cx.notify();
1652    }
1653
1654    pub fn undo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1655        let was_dirty = self.is_dirty();
1656        let old_version = self.version.clone();
1657
1658        if let Some((transaction_id, operation)) = self.text.undo() {
1659            self.send_operation(Operation::Buffer(operation), cx);
1660            self.did_edit(&old_version, was_dirty, cx);
1661            Some(transaction_id)
1662        } else {
1663            None
1664        }
1665    }
1666
1667    pub fn undo_to_transaction(
1668        &mut self,
1669        transaction_id: TransactionId,
1670        cx: &mut ModelContext<Self>,
1671    ) -> bool {
1672        let was_dirty = self.is_dirty();
1673        let old_version = self.version.clone();
1674
1675        let operations = self.text.undo_to_transaction(transaction_id);
1676        let undone = !operations.is_empty();
1677        for operation in operations {
1678            self.send_operation(Operation::Buffer(operation), cx);
1679        }
1680        if undone {
1681            self.did_edit(&old_version, was_dirty, cx)
1682        }
1683        undone
1684    }
1685
1686    pub fn redo(&mut self, cx: &mut ModelContext<Self>) -> Option<TransactionId> {
1687        let was_dirty = self.is_dirty();
1688        let old_version = self.version.clone();
1689
1690        if let Some((transaction_id, operation)) = self.text.redo() {
1691            self.send_operation(Operation::Buffer(operation), cx);
1692            self.did_edit(&old_version, was_dirty, cx);
1693            Some(transaction_id)
1694        } else {
1695            None
1696        }
1697    }
1698
1699    pub fn redo_to_transaction(
1700        &mut self,
1701        transaction_id: TransactionId,
1702        cx: &mut ModelContext<Self>,
1703    ) -> bool {
1704        let was_dirty = self.is_dirty();
1705        let old_version = self.version.clone();
1706
1707        let operations = self.text.redo_to_transaction(transaction_id);
1708        let redone = !operations.is_empty();
1709        for operation in operations {
1710            self.send_operation(Operation::Buffer(operation), cx);
1711        }
1712        if redone {
1713            self.did_edit(&old_version, was_dirty, cx)
1714        }
1715        redone
1716    }
1717
1718    pub fn set_completion_triggers(&mut self, triggers: Vec<String>, cx: &mut ModelContext<Self>) {
1719        self.completion_triggers = triggers.clone();
1720        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
1721        self.send_operation(
1722            Operation::UpdateCompletionTriggers {
1723                triggers,
1724                lamport_timestamp: self.completion_triggers_timestamp,
1725            },
1726            cx,
1727        );
1728        cx.notify();
1729    }
1730
1731    pub fn completion_triggers(&self) -> &[String] {
1732        &self.completion_triggers
1733    }
1734}
1735
1736#[cfg(any(test, feature = "test-support"))]
1737impl Buffer {
1738    pub fn edit_via_marked_text(
1739        &mut self,
1740        marked_string: &str,
1741        autoindent_mode: Option<AutoindentMode>,
1742        cx: &mut ModelContext<Self>,
1743    ) {
1744        let edits = self.edits_for_marked_text(marked_string);
1745        self.edit(edits, autoindent_mode, cx);
1746    }
1747
1748    pub fn set_group_interval(&mut self, group_interval: Duration) {
1749        self.text.set_group_interval(group_interval);
1750    }
1751
1752    pub fn randomly_edit<T>(
1753        &mut self,
1754        rng: &mut T,
1755        old_range_count: usize,
1756        cx: &mut ModelContext<Self>,
1757    ) where
1758        T: rand::Rng,
1759    {
1760        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
1761        let mut last_end = None;
1762        for _ in 0..old_range_count {
1763            if last_end.map_or(false, |last_end| last_end >= self.len()) {
1764                break;
1765            }
1766
1767            let new_start = last_end.map_or(0, |last_end| last_end + 1);
1768            let mut range = self.random_byte_range(new_start, rng);
1769            if rng.gen_bool(0.2) {
1770                mem::swap(&mut range.start, &mut range.end);
1771            }
1772            last_end = Some(range.end);
1773
1774            let new_text_len = rng.gen_range(0..10);
1775            let new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
1776
1777            edits.push((range, new_text));
1778        }
1779        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
1780        self.edit(edits, None, cx);
1781    }
1782
1783    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut ModelContext<Self>) {
1784        let was_dirty = self.is_dirty();
1785        let old_version = self.version.clone();
1786
1787        let ops = self.text.randomly_undo_redo(rng);
1788        if !ops.is_empty() {
1789            for op in ops {
1790                self.send_operation(Operation::Buffer(op), cx);
1791                self.did_edit(&old_version, was_dirty, cx);
1792            }
1793        }
1794    }
1795}
1796
1797impl Entity for Buffer {
1798    type Event = Event;
1799}
1800
1801impl Deref for Buffer {
1802    type Target = TextBuffer;
1803
1804    fn deref(&self) -> &Self::Target {
1805        &self.text
1806    }
1807}
1808
1809impl BufferSnapshot {
1810    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
1811        indent_size_for_line(self, row)
1812    }
1813
1814    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &AppContext) -> IndentSize {
1815        let settings = language_settings(self.language_at(position), self.file(), cx);
1816        if settings.hard_tabs {
1817            IndentSize::tab()
1818        } else {
1819            IndentSize::spaces(settings.tab_size.get())
1820        }
1821    }
1822
1823    pub fn suggested_indents(
1824        &self,
1825        rows: impl Iterator<Item = u32>,
1826        single_indent_size: IndentSize,
1827    ) -> BTreeMap<u32, IndentSize> {
1828        let mut result = BTreeMap::new();
1829
1830        for row_range in contiguous_ranges(rows, 10) {
1831            let suggestions = match self.suggest_autoindents(row_range.clone()) {
1832                Some(suggestions) => suggestions,
1833                _ => break,
1834            };
1835
1836            for (row, suggestion) in row_range.zip(suggestions) {
1837                let indent_size = if let Some(suggestion) = suggestion {
1838                    result
1839                        .get(&suggestion.basis_row)
1840                        .copied()
1841                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
1842                        .with_delta(suggestion.delta, single_indent_size)
1843                } else {
1844                    self.indent_size_for_line(row)
1845                };
1846
1847                result.insert(row, indent_size);
1848            }
1849        }
1850
1851        result
1852    }
1853
1854    fn suggest_autoindents(
1855        &self,
1856        row_range: Range<u32>,
1857    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
1858        let config = &self.language.as_ref()?.config;
1859        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
1860
1861        // Find the suggested indentation ranges based on the syntax tree.
1862        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
1863        let end = Point::new(row_range.end, 0);
1864        let range = (start..end).to_offset(&self.text);
1865        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1866            Some(&grammar.indents_config.as_ref()?.query)
1867        });
1868        let indent_configs = matches
1869            .grammars()
1870            .iter()
1871            .map(|grammar| grammar.indents_config.as_ref().unwrap())
1872            .collect::<Vec<_>>();
1873
1874        let mut indent_ranges = Vec::<Range<Point>>::new();
1875        let mut outdent_positions = Vec::<Point>::new();
1876        while let Some(mat) = matches.peek() {
1877            let mut start: Option<Point> = None;
1878            let mut end: Option<Point> = None;
1879
1880            let config = &indent_configs[mat.grammar_index];
1881            for capture in mat.captures {
1882                if capture.index == config.indent_capture_ix {
1883                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
1884                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
1885                } else if Some(capture.index) == config.start_capture_ix {
1886                    start = Some(Point::from_ts_point(capture.node.end_position()));
1887                } else if Some(capture.index) == config.end_capture_ix {
1888                    end = Some(Point::from_ts_point(capture.node.start_position()));
1889                } else if Some(capture.index) == config.outdent_capture_ix {
1890                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
1891                }
1892            }
1893
1894            matches.advance();
1895            if let Some((start, end)) = start.zip(end) {
1896                if start.row == end.row {
1897                    continue;
1898                }
1899
1900                let range = start..end;
1901                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
1902                    Err(ix) => indent_ranges.insert(ix, range),
1903                    Ok(ix) => {
1904                        let prev_range = &mut indent_ranges[ix];
1905                        prev_range.end = prev_range.end.max(range.end);
1906                    }
1907                }
1908            }
1909        }
1910
1911        let mut error_ranges = Vec::<Range<Point>>::new();
1912        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
1913            Some(&grammar.error_query)
1914        });
1915        while let Some(mat) = matches.peek() {
1916            let node = mat.captures[0].node;
1917            let start = Point::from_ts_point(node.start_position());
1918            let end = Point::from_ts_point(node.end_position());
1919            let range = start..end;
1920            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
1921                Ok(ix) | Err(ix) => ix,
1922            };
1923            let mut end_ix = ix;
1924            while let Some(existing_range) = error_ranges.get(end_ix) {
1925                if existing_range.end < end {
1926                    end_ix += 1;
1927                } else {
1928                    break;
1929                }
1930            }
1931            error_ranges.splice(ix..end_ix, [range]);
1932            matches.advance();
1933        }
1934
1935        outdent_positions.sort();
1936        for outdent_position in outdent_positions {
1937            // find the innermost indent range containing this outdent_position
1938            // set its end to the outdent position
1939            if let Some(range_to_truncate) = indent_ranges
1940                .iter_mut()
1941                .filter(|indent_range| indent_range.contains(&outdent_position))
1942                .last()
1943            {
1944                range_to_truncate.end = outdent_position;
1945            }
1946        }
1947
1948        // Find the suggested indentation increases and decreased based on regexes.
1949        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
1950        self.for_each_line(
1951            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
1952                ..Point::new(row_range.end, 0),
1953            |row, line| {
1954                if config
1955                    .decrease_indent_pattern
1956                    .as_ref()
1957                    .map_or(false, |regex| regex.is_match(line))
1958                {
1959                    indent_change_rows.push((row, Ordering::Less));
1960                }
1961                if config
1962                    .increase_indent_pattern
1963                    .as_ref()
1964                    .map_or(false, |regex| regex.is_match(line))
1965                {
1966                    indent_change_rows.push((row + 1, Ordering::Greater));
1967                }
1968            },
1969        );
1970
1971        let mut indent_changes = indent_change_rows.into_iter().peekable();
1972        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
1973            prev_non_blank_row.unwrap_or(0)
1974        } else {
1975            row_range.start.saturating_sub(1)
1976        };
1977        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
1978        Some(row_range.map(move |row| {
1979            let row_start = Point::new(row, self.indent_size_for_line(row).len);
1980
1981            let mut indent_from_prev_row = false;
1982            let mut outdent_from_prev_row = false;
1983            let mut outdent_to_row = u32::MAX;
1984
1985            while let Some((indent_row, delta)) = indent_changes.peek() {
1986                match indent_row.cmp(&row) {
1987                    Ordering::Equal => match delta {
1988                        Ordering::Less => outdent_from_prev_row = true,
1989                        Ordering::Greater => indent_from_prev_row = true,
1990                        _ => {}
1991                    },
1992
1993                    Ordering::Greater => break,
1994                    Ordering::Less => {}
1995                }
1996
1997                indent_changes.next();
1998            }
1999
2000            for range in &indent_ranges {
2001                if range.start.row >= row {
2002                    break;
2003                }
2004                if range.start.row == prev_row && range.end > row_start {
2005                    indent_from_prev_row = true;
2006                }
2007                if range.end > prev_row_start && range.end <= row_start {
2008                    outdent_to_row = outdent_to_row.min(range.start.row);
2009                }
2010            }
2011
2012            let within_error = error_ranges
2013                .iter()
2014                .any(|e| e.start.row < row && e.end > row_start);
2015
2016            let suggestion = if outdent_to_row == prev_row
2017                || (outdent_from_prev_row && indent_from_prev_row)
2018            {
2019                Some(IndentSuggestion {
2020                    basis_row: prev_row,
2021                    delta: Ordering::Equal,
2022                    within_error,
2023                })
2024            } else if indent_from_prev_row {
2025                Some(IndentSuggestion {
2026                    basis_row: prev_row,
2027                    delta: Ordering::Greater,
2028                    within_error,
2029                })
2030            } else if outdent_to_row < prev_row {
2031                Some(IndentSuggestion {
2032                    basis_row: outdent_to_row,
2033                    delta: Ordering::Equal,
2034                    within_error,
2035                })
2036            } else if outdent_from_prev_row {
2037                Some(IndentSuggestion {
2038                    basis_row: prev_row,
2039                    delta: Ordering::Less,
2040                    within_error,
2041                })
2042            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
2043            {
2044                Some(IndentSuggestion {
2045                    basis_row: prev_row,
2046                    delta: Ordering::Equal,
2047                    within_error,
2048                })
2049            } else {
2050                None
2051            };
2052
2053            prev_row = row;
2054            prev_row_start = row_start;
2055            suggestion
2056        }))
2057    }
2058
2059    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
2060        while row > 0 {
2061            row -= 1;
2062            if !self.is_line_blank(row) {
2063                return Some(row);
2064            }
2065        }
2066        None
2067    }
2068
2069    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
2070        let range = range.start.to_offset(self)..range.end.to_offset(self);
2071
2072        let mut syntax = None;
2073        let mut diagnostic_endpoints = Vec::new();
2074        if language_aware {
2075            let captures = self.syntax.captures(range.clone(), &self.text, |grammar| {
2076                grammar.highlights_query.as_ref()
2077            });
2078            let highlight_maps = captures
2079                .grammars()
2080                .into_iter()
2081                .map(|grammar| grammar.highlight_map())
2082                .collect();
2083            syntax = Some((captures, highlight_maps));
2084            for entry in self.diagnostics_in_range::<_, usize>(range.clone(), false) {
2085                diagnostic_endpoints.push(DiagnosticEndpoint {
2086                    offset: entry.range.start,
2087                    is_start: true,
2088                    severity: entry.diagnostic.severity,
2089                    is_unnecessary: entry.diagnostic.is_unnecessary,
2090                });
2091                diagnostic_endpoints.push(DiagnosticEndpoint {
2092                    offset: entry.range.end,
2093                    is_start: false,
2094                    severity: entry.diagnostic.severity,
2095                    is_unnecessary: entry.diagnostic.is_unnecessary,
2096                });
2097            }
2098            diagnostic_endpoints
2099                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
2100        }
2101
2102        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostic_endpoints)
2103    }
2104
2105    pub fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
2106        let mut line = String::new();
2107        let mut row = range.start.row;
2108        for chunk in self
2109            .as_rope()
2110            .chunks_in_range(range.to_offset(self))
2111            .chain(["\n"])
2112        {
2113            for (newline_ix, text) in chunk.split('\n').enumerate() {
2114                if newline_ix > 0 {
2115                    callback(row, &line);
2116                    row += 1;
2117                    line.clear();
2118                }
2119                line.push_str(text);
2120            }
2121        }
2122    }
2123
2124    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayerInfo> + '_ {
2125        self.syntax.layers_for_range(0..self.len(), &self.text)
2126    }
2127
2128    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayerInfo> {
2129        let offset = position.to_offset(self);
2130        self.syntax
2131            .layers_for_range(offset..offset, &self.text)
2132            .filter(|l| l.node().end_byte() > offset)
2133            .last()
2134    }
2135
2136    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
2137        self.syntax_layer_at(position)
2138            .map(|info| info.language)
2139            .or(self.language.as_ref())
2140    }
2141
2142    pub fn settings_at<'a, D: ToOffset>(
2143        &self,
2144        position: D,
2145        cx: &'a AppContext,
2146    ) -> &'a LanguageSettings {
2147        language_settings(self.language_at(position), self.file.as_ref(), cx)
2148    }
2149
2150    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
2151        let offset = position.to_offset(self);
2152        let mut scope = None;
2153        let mut smallest_range: Option<Range<usize>> = None;
2154
2155        // Use the layer that has the smallest node intersecting the given point.
2156        for layer in self.syntax.layers_for_range(offset..offset, &self.text) {
2157            let mut cursor = layer.node().walk();
2158
2159            let mut range = None;
2160            loop {
2161                let child_range = cursor.node().byte_range();
2162                if !child_range.to_inclusive().contains(&offset) {
2163                    break;
2164                }
2165
2166                range = Some(child_range);
2167                if cursor.goto_first_child_for_byte(offset).is_none() {
2168                    break;
2169                }
2170            }
2171
2172            if let Some(range) = range {
2173                if smallest_range
2174                    .as_ref()
2175                    .map_or(true, |smallest_range| range.len() < smallest_range.len())
2176                {
2177                    smallest_range = Some(range);
2178                    scope = Some(LanguageScope {
2179                        language: layer.language.clone(),
2180                        override_id: layer.override_id(offset, &self.text),
2181                    });
2182                }
2183            }
2184        }
2185
2186        scope.or_else(|| {
2187            self.language.clone().map(|language| LanguageScope {
2188                language,
2189                override_id: None,
2190            })
2191        })
2192    }
2193
2194    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
2195        let mut start = start.to_offset(self);
2196        let mut end = start;
2197        let mut next_chars = self.chars_at(start).peekable();
2198        let mut prev_chars = self.reversed_chars_at(start).peekable();
2199
2200        let language = self.language_at(start);
2201        let kind = |c| char_kind(language, c);
2202        let word_kind = cmp::max(
2203            prev_chars.peek().copied().map(kind),
2204            next_chars.peek().copied().map(kind),
2205        );
2206
2207        for ch in prev_chars {
2208            if Some(kind(ch)) == word_kind && ch != '\n' {
2209                start -= ch.len_utf8();
2210            } else {
2211                break;
2212            }
2213        }
2214
2215        for ch in next_chars {
2216            if Some(kind(ch)) == word_kind && ch != '\n' {
2217                end += ch.len_utf8();
2218            } else {
2219                break;
2220            }
2221        }
2222
2223        (start..end, word_kind)
2224    }
2225
2226    pub fn range_for_syntax_ancestor<T: ToOffset>(&self, range: Range<T>) -> Option<Range<usize>> {
2227        let range = range.start.to_offset(self)..range.end.to_offset(self);
2228        let mut result: Option<Range<usize>> = None;
2229        'outer: for layer in self.syntax.layers_for_range(range.clone(), &self.text) {
2230            let mut cursor = layer.node().walk();
2231
2232            // Descend to the first leaf that touches the start of the range,
2233            // and if the range is non-empty, extends beyond the start.
2234            while cursor.goto_first_child_for_byte(range.start).is_some() {
2235                if !range.is_empty() && cursor.node().end_byte() == range.start {
2236                    cursor.goto_next_sibling();
2237                }
2238            }
2239
2240            // Ascend to the smallest ancestor that strictly contains the range.
2241            loop {
2242                let node_range = cursor.node().byte_range();
2243                if node_range.start <= range.start
2244                    && node_range.end >= range.end
2245                    && node_range.len() > range.len()
2246                {
2247                    break;
2248                }
2249                if !cursor.goto_parent() {
2250                    continue 'outer;
2251                }
2252            }
2253
2254            let left_node = cursor.node();
2255            let mut layer_result = left_node.byte_range();
2256
2257            // For an empty range, try to find another node immediately to the right of the range.
2258            if left_node.end_byte() == range.start {
2259                let mut right_node = None;
2260                while !cursor.goto_next_sibling() {
2261                    if !cursor.goto_parent() {
2262                        break;
2263                    }
2264                }
2265
2266                while cursor.node().start_byte() == range.start {
2267                    right_node = Some(cursor.node());
2268                    if !cursor.goto_first_child() {
2269                        break;
2270                    }
2271                }
2272
2273                // If there is a candidate node on both sides of the (empty) range, then
2274                // decide between the two by favoring a named node over an anonymous token.
2275                // If both nodes are the same in that regard, favor the right one.
2276                if let Some(right_node) = right_node {
2277                    if right_node.is_named() || !left_node.is_named() {
2278                        layer_result = right_node.byte_range();
2279                    }
2280                }
2281            }
2282
2283            if let Some(previous_result) = &result {
2284                if previous_result.len() < layer_result.len() {
2285                    continue;
2286                }
2287            }
2288            result = Some(layer_result);
2289        }
2290
2291        result
2292    }
2293
2294    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
2295        self.outline_items_containing(0..self.len(), true, theme)
2296            .map(Outline::new)
2297    }
2298
2299    pub fn symbols_containing<T: ToOffset>(
2300        &self,
2301        position: T,
2302        theme: Option<&SyntaxTheme>,
2303    ) -> Option<Vec<OutlineItem<Anchor>>> {
2304        let position = position.to_offset(self);
2305        let mut items = self.outline_items_containing(
2306            position.saturating_sub(1)..self.len().min(position + 1),
2307            false,
2308            theme,
2309        )?;
2310        let mut prev_depth = None;
2311        items.retain(|item| {
2312            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
2313            prev_depth = Some(item.depth);
2314            result
2315        });
2316        Some(items)
2317    }
2318
2319    fn outline_items_containing(
2320        &self,
2321        range: Range<usize>,
2322        include_extra_context: bool,
2323        theme: Option<&SyntaxTheme>,
2324    ) -> Option<Vec<OutlineItem<Anchor>>> {
2325        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2326            grammar.outline_config.as_ref().map(|c| &c.query)
2327        });
2328        let configs = matches
2329            .grammars()
2330            .iter()
2331            .map(|g| g.outline_config.as_ref().unwrap())
2332            .collect::<Vec<_>>();
2333
2334        let mut stack = Vec::<Range<usize>>::new();
2335        let mut items = Vec::new();
2336        while let Some(mat) = matches.peek() {
2337            let config = &configs[mat.grammar_index];
2338            let item_node = mat.captures.iter().find_map(|cap| {
2339                if cap.index == config.item_capture_ix {
2340                    Some(cap.node)
2341                } else {
2342                    None
2343                }
2344            })?;
2345
2346            let item_range = item_node.byte_range();
2347            if item_range.end < range.start || item_range.start > range.end {
2348                matches.advance();
2349                continue;
2350            }
2351
2352            let mut buffer_ranges = Vec::new();
2353            for capture in mat.captures {
2354                let node_is_name;
2355                if capture.index == config.name_capture_ix {
2356                    node_is_name = true;
2357                } else if Some(capture.index) == config.context_capture_ix
2358                    || (Some(capture.index) == config.extra_context_capture_ix
2359                        && include_extra_context)
2360                {
2361                    node_is_name = false;
2362                } else {
2363                    continue;
2364                }
2365
2366                let mut range = capture.node.start_byte()..capture.node.end_byte();
2367                let start = capture.node.start_position();
2368                if capture.node.end_position().row > start.row {
2369                    range.end =
2370                        range.start + self.line_len(start.row as u32) as usize - start.column;
2371                }
2372
2373                buffer_ranges.push((range, node_is_name));
2374            }
2375
2376            if buffer_ranges.is_empty() {
2377                continue;
2378            }
2379
2380            let mut text = String::new();
2381            let mut highlight_ranges = Vec::new();
2382            let mut name_ranges = Vec::new();
2383            let mut chunks = self.chunks(
2384                buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
2385                true,
2386            );
2387            let mut last_buffer_range_end = 0;
2388            for (buffer_range, is_name) in buffer_ranges {
2389                if !text.is_empty() && buffer_range.start > last_buffer_range_end {
2390                    text.push(' ');
2391                }
2392                last_buffer_range_end = buffer_range.end;
2393                if is_name {
2394                    let mut start = text.len();
2395                    let end = start + buffer_range.len();
2396
2397                    // When multiple names are captured, then the matcheable text
2398                    // includes the whitespace in between the names.
2399                    if !name_ranges.is_empty() {
2400                        start -= 1;
2401                    }
2402
2403                    name_ranges.push(start..end);
2404                }
2405
2406                let mut offset = buffer_range.start;
2407                chunks.seek(offset);
2408                for mut chunk in chunks.by_ref() {
2409                    if chunk.text.len() > buffer_range.end - offset {
2410                        chunk.text = &chunk.text[0..(buffer_range.end - offset)];
2411                        offset = buffer_range.end;
2412                    } else {
2413                        offset += chunk.text.len();
2414                    }
2415                    let style = chunk
2416                        .syntax_highlight_id
2417                        .zip(theme)
2418                        .and_then(|(highlight, theme)| highlight.style(theme));
2419                    if let Some(style) = style {
2420                        let start = text.len();
2421                        let end = start + chunk.text.len();
2422                        highlight_ranges.push((start..end, style));
2423                    }
2424                    text.push_str(chunk.text);
2425                    if offset >= buffer_range.end {
2426                        break;
2427                    }
2428                }
2429            }
2430
2431            matches.advance();
2432            while stack.last().map_or(false, |prev_range| {
2433                prev_range.start > item_range.start || prev_range.end < item_range.end
2434            }) {
2435                stack.pop();
2436            }
2437            stack.push(item_range.clone());
2438
2439            items.push(OutlineItem {
2440                depth: stack.len() - 1,
2441                range: self.anchor_after(item_range.start)..self.anchor_before(item_range.end),
2442                text,
2443                highlight_ranges,
2444                name_ranges,
2445            })
2446        }
2447        Some(items)
2448    }
2449
2450    /// Returns bracket range pairs overlapping or adjacent to `range`
2451    pub fn bracket_ranges<'a, T: ToOffset>(
2452        &'a self,
2453        range: Range<T>,
2454    ) -> impl Iterator<Item = (Range<usize>, Range<usize>)> + 'a {
2455        // Find bracket pairs that *inclusively* contain the given range.
2456        let range = range.start.to_offset(self).saturating_sub(1)
2457            ..self.len().min(range.end.to_offset(self) + 1);
2458
2459        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2460            grammar.brackets_config.as_ref().map(|c| &c.query)
2461        });
2462        let configs = matches
2463            .grammars()
2464            .iter()
2465            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
2466            .collect::<Vec<_>>();
2467
2468        iter::from_fn(move || {
2469            while let Some(mat) = matches.peek() {
2470                let mut open = None;
2471                let mut close = None;
2472                let config = &configs[mat.grammar_index];
2473                for capture in mat.captures {
2474                    if capture.index == config.open_capture_ix {
2475                        open = Some(capture.node.byte_range());
2476                    } else if capture.index == config.close_capture_ix {
2477                        close = Some(capture.node.byte_range());
2478                    }
2479                }
2480
2481                matches.advance();
2482
2483                let Some((open, close)) = open.zip(close) else {
2484                    continue;
2485                };
2486
2487                let bracket_range = open.start..=close.end;
2488                if !bracket_range.overlaps(&range) {
2489                    continue;
2490                }
2491
2492                return Some((open, close));
2493            }
2494            None
2495        })
2496    }
2497
2498    #[allow(clippy::type_complexity)]
2499    pub fn remote_selections_in_range(
2500        &self,
2501        range: Range<Anchor>,
2502    ) -> impl Iterator<
2503        Item = (
2504            ReplicaId,
2505            bool,
2506            CursorShape,
2507            impl Iterator<Item = &Selection<Anchor>> + '_,
2508        ),
2509    > + '_ {
2510        self.remote_selections
2511            .iter()
2512            .filter(|(replica_id, set)| {
2513                **replica_id != self.text.replica_id() && !set.selections.is_empty()
2514            })
2515            .map(move |(replica_id, set)| {
2516                let start_ix = match set.selections.binary_search_by(|probe| {
2517                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
2518                }) {
2519                    Ok(ix) | Err(ix) => ix,
2520                };
2521                let end_ix = match set.selections.binary_search_by(|probe| {
2522                    probe.start.cmp(&range.end, self).then(Ordering::Less)
2523                }) {
2524                    Ok(ix) | Err(ix) => ix,
2525                };
2526
2527                (
2528                    *replica_id,
2529                    set.line_mode,
2530                    set.cursor_shape,
2531                    set.selections[start_ix..end_ix].iter(),
2532                )
2533            })
2534    }
2535
2536    pub fn git_diff_hunks_in_row_range<'a>(
2537        &'a self,
2538        range: Range<u32>,
2539    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2540        self.git_diff.hunks_in_row_range(range, self)
2541    }
2542
2543    pub fn git_diff_hunks_intersecting_range<'a>(
2544        &'a self,
2545        range: Range<Anchor>,
2546    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2547        self.git_diff.hunks_intersecting_range(range, self)
2548    }
2549
2550    pub fn git_diff_hunks_intersecting_range_rev<'a>(
2551        &'a self,
2552        range: Range<Anchor>,
2553    ) -> impl 'a + Iterator<Item = git::diff::DiffHunk<u32>> {
2554        self.git_diff.hunks_intersecting_range_rev(range, self)
2555    }
2556
2557    pub fn diagnostics_in_range<'a, T, O>(
2558        &'a self,
2559        search_range: Range<T>,
2560        reversed: bool,
2561    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2562    where
2563        T: 'a + Clone + ToOffset,
2564        O: 'a + FromAnchor + Ord,
2565    {
2566        let mut iterators: Vec<_> = self
2567            .diagnostics
2568            .iter()
2569            .map(|(_, collection)| {
2570                collection
2571                    .range::<T, O>(search_range.clone(), self, true, reversed)
2572                    .peekable()
2573            })
2574            .collect();
2575
2576        std::iter::from_fn(move || {
2577            let (next_ix, _) = iterators
2578                .iter_mut()
2579                .enumerate()
2580                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
2581                .min_by(|(_, a), (_, b)| a.range.start.cmp(&b.range.start))?;
2582            iterators[next_ix].next()
2583        })
2584    }
2585
2586    pub fn diagnostic_groups(
2587        &self,
2588        language_server_id: Option<LanguageServerId>,
2589    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
2590        let mut groups = Vec::new();
2591
2592        if let Some(language_server_id) = language_server_id {
2593            if let Ok(ix) = self
2594                .diagnostics
2595                .binary_search_by_key(&language_server_id, |e| e.0)
2596            {
2597                self.diagnostics[ix]
2598                    .1
2599                    .groups(language_server_id, &mut groups, self);
2600            }
2601        } else {
2602            for (language_server_id, diagnostics) in self.diagnostics.iter() {
2603                diagnostics.groups(*language_server_id, &mut groups, self);
2604            }
2605        }
2606
2607        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
2608            let a_start = &group_a.entries[group_a.primary_ix].range.start;
2609            let b_start = &group_b.entries[group_b.primary_ix].range.start;
2610            a_start.cmp(b_start, self).then_with(|| id_a.cmp(&id_b))
2611        });
2612
2613        groups
2614    }
2615
2616    pub fn diagnostic_group<'a, O>(
2617        &'a self,
2618        group_id: usize,
2619    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
2620    where
2621        O: 'a + FromAnchor,
2622    {
2623        self.diagnostics
2624            .iter()
2625            .flat_map(move |(_, set)| set.group(group_id, self))
2626    }
2627
2628    pub fn diagnostics_update_count(&self) -> usize {
2629        self.diagnostics_update_count
2630    }
2631
2632    pub fn parse_count(&self) -> usize {
2633        self.parse_count
2634    }
2635
2636    pub fn selections_update_count(&self) -> usize {
2637        self.selections_update_count
2638    }
2639
2640    pub fn file(&self) -> Option<&Arc<dyn File>> {
2641        self.file.as_ref()
2642    }
2643
2644    pub fn resolve_file_path(&self, cx: &AppContext, include_root: bool) -> Option<PathBuf> {
2645        if let Some(file) = self.file() {
2646            if file.path().file_name().is_none() || include_root {
2647                Some(file.full_path(cx))
2648            } else {
2649                Some(file.path().to_path_buf())
2650            }
2651        } else {
2652            None
2653        }
2654    }
2655
2656    pub fn file_update_count(&self) -> usize {
2657        self.file_update_count
2658    }
2659
2660    pub fn git_diff_update_count(&self) -> usize {
2661        self.git_diff_update_count
2662    }
2663}
2664
2665fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
2666    indent_size_for_text(text.chars_at(Point::new(row, 0)))
2667}
2668
2669pub fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
2670    let mut result = IndentSize::spaces(0);
2671    for c in text {
2672        let kind = match c {
2673            ' ' => IndentKind::Space,
2674            '\t' => IndentKind::Tab,
2675            _ => break,
2676        };
2677        if result.len == 0 {
2678            result.kind = kind;
2679        }
2680        result.len += 1;
2681    }
2682    result
2683}
2684
2685impl Clone for BufferSnapshot {
2686    fn clone(&self) -> Self {
2687        Self {
2688            text: self.text.clone(),
2689            git_diff: self.git_diff.clone(),
2690            syntax: self.syntax.clone(),
2691            file: self.file.clone(),
2692            remote_selections: self.remote_selections.clone(),
2693            diagnostics: self.diagnostics.clone(),
2694            selections_update_count: self.selections_update_count,
2695            diagnostics_update_count: self.diagnostics_update_count,
2696            file_update_count: self.file_update_count,
2697            git_diff_update_count: self.git_diff_update_count,
2698            language: self.language.clone(),
2699            parse_count: self.parse_count,
2700        }
2701    }
2702}
2703
2704impl Deref for BufferSnapshot {
2705    type Target = text::BufferSnapshot;
2706
2707    fn deref(&self) -> &Self::Target {
2708        &self.text
2709    }
2710}
2711
2712unsafe impl<'a> Send for BufferChunks<'a> {}
2713
2714impl<'a> BufferChunks<'a> {
2715    pub(crate) fn new(
2716        text: &'a Rope,
2717        range: Range<usize>,
2718        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
2719        diagnostic_endpoints: Vec<DiagnosticEndpoint>,
2720    ) -> Self {
2721        let mut highlights = None;
2722        if let Some((captures, highlight_maps)) = syntax {
2723            highlights = Some(BufferChunkHighlights {
2724                captures,
2725                next_capture: None,
2726                stack: Default::default(),
2727                highlight_maps,
2728            })
2729        }
2730
2731        let diagnostic_endpoints = diagnostic_endpoints.into_iter().peekable();
2732        let chunks = text.chunks_in_range(range.clone());
2733
2734        BufferChunks {
2735            range,
2736            chunks,
2737            diagnostic_endpoints,
2738            error_depth: 0,
2739            warning_depth: 0,
2740            information_depth: 0,
2741            hint_depth: 0,
2742            unnecessary_depth: 0,
2743            highlights,
2744        }
2745    }
2746
2747    pub fn seek(&mut self, offset: usize) {
2748        self.range.start = offset;
2749        self.chunks.seek(self.range.start);
2750        if let Some(highlights) = self.highlights.as_mut() {
2751            highlights
2752                .stack
2753                .retain(|(end_offset, _)| *end_offset > offset);
2754            if let Some(capture) = &highlights.next_capture {
2755                if offset >= capture.node.start_byte() {
2756                    let next_capture_end = capture.node.end_byte();
2757                    if offset < next_capture_end {
2758                        highlights.stack.push((
2759                            next_capture_end,
2760                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
2761                        ));
2762                    }
2763                    highlights.next_capture.take();
2764                }
2765            }
2766            highlights.captures.set_byte_range(self.range.clone());
2767        }
2768    }
2769
2770    pub fn offset(&self) -> usize {
2771        self.range.start
2772    }
2773
2774    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
2775        let depth = match endpoint.severity {
2776            DiagnosticSeverity::ERROR => &mut self.error_depth,
2777            DiagnosticSeverity::WARNING => &mut self.warning_depth,
2778            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
2779            DiagnosticSeverity::HINT => &mut self.hint_depth,
2780            _ => return,
2781        };
2782        if endpoint.is_start {
2783            *depth += 1;
2784        } else {
2785            *depth -= 1;
2786        }
2787
2788        if endpoint.is_unnecessary {
2789            if endpoint.is_start {
2790                self.unnecessary_depth += 1;
2791            } else {
2792                self.unnecessary_depth -= 1;
2793            }
2794        }
2795    }
2796
2797    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
2798        if self.error_depth > 0 {
2799            Some(DiagnosticSeverity::ERROR)
2800        } else if self.warning_depth > 0 {
2801            Some(DiagnosticSeverity::WARNING)
2802        } else if self.information_depth > 0 {
2803            Some(DiagnosticSeverity::INFORMATION)
2804        } else if self.hint_depth > 0 {
2805            Some(DiagnosticSeverity::HINT)
2806        } else {
2807            None
2808        }
2809    }
2810
2811    fn current_code_is_unnecessary(&self) -> bool {
2812        self.unnecessary_depth > 0
2813    }
2814}
2815
2816impl<'a> Iterator for BufferChunks<'a> {
2817    type Item = Chunk<'a>;
2818
2819    fn next(&mut self) -> Option<Self::Item> {
2820        let mut next_capture_start = usize::MAX;
2821        let mut next_diagnostic_endpoint = usize::MAX;
2822
2823        if let Some(highlights) = self.highlights.as_mut() {
2824            while let Some((parent_capture_end, _)) = highlights.stack.last() {
2825                if *parent_capture_end <= self.range.start {
2826                    highlights.stack.pop();
2827                } else {
2828                    break;
2829                }
2830            }
2831
2832            if highlights.next_capture.is_none() {
2833                highlights.next_capture = highlights.captures.next();
2834            }
2835
2836            while let Some(capture) = highlights.next_capture.as_ref() {
2837                if self.range.start < capture.node.start_byte() {
2838                    next_capture_start = capture.node.start_byte();
2839                    break;
2840                } else {
2841                    let highlight_id =
2842                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
2843                    highlights
2844                        .stack
2845                        .push((capture.node.end_byte(), highlight_id));
2846                    highlights.next_capture = highlights.captures.next();
2847                }
2848            }
2849        }
2850
2851        while let Some(endpoint) = self.diagnostic_endpoints.peek().copied() {
2852            if endpoint.offset <= self.range.start {
2853                self.update_diagnostic_depths(endpoint);
2854                self.diagnostic_endpoints.next();
2855            } else {
2856                next_diagnostic_endpoint = endpoint.offset;
2857                break;
2858            }
2859        }
2860
2861        if let Some(chunk) = self.chunks.peek() {
2862            let chunk_start = self.range.start;
2863            let mut chunk_end = (self.chunks.offset() + chunk.len())
2864                .min(next_capture_start)
2865                .min(next_diagnostic_endpoint);
2866            let mut highlight_id = None;
2867            if let Some(highlights) = self.highlights.as_ref() {
2868                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
2869                    chunk_end = chunk_end.min(*parent_capture_end);
2870                    highlight_id = Some(*parent_highlight_id);
2871                }
2872            }
2873
2874            let slice =
2875                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
2876            self.range.start = chunk_end;
2877            if self.range.start == self.chunks.offset() + chunk.len() {
2878                self.chunks.next().unwrap();
2879            }
2880
2881            Some(Chunk {
2882                text: slice,
2883                syntax_highlight_id: highlight_id,
2884                diagnostic_severity: self.current_diagnostic_severity(),
2885                is_unnecessary: self.current_code_is_unnecessary(),
2886                ..Default::default()
2887            })
2888        } else {
2889            None
2890        }
2891    }
2892}
2893
2894impl operation_queue::Operation for Operation {
2895    fn lamport_timestamp(&self) -> clock::Lamport {
2896        match self {
2897            Operation::Buffer(_) => {
2898                unreachable!("buffer operations should never be deferred at this layer")
2899            }
2900            Operation::UpdateDiagnostics {
2901                lamport_timestamp, ..
2902            }
2903            | Operation::UpdateSelections {
2904                lamport_timestamp, ..
2905            }
2906            | Operation::UpdateCompletionTriggers {
2907                lamport_timestamp, ..
2908            } => *lamport_timestamp,
2909        }
2910    }
2911}
2912
2913impl Default for Diagnostic {
2914    fn default() -> Self {
2915        Self {
2916            source: Default::default(),
2917            code: None,
2918            severity: DiagnosticSeverity::ERROR,
2919            message: Default::default(),
2920            group_id: 0,
2921            is_primary: false,
2922            is_valid: true,
2923            is_disk_based: false,
2924            is_unnecessary: false,
2925        }
2926    }
2927}
2928
2929impl IndentSize {
2930    pub fn spaces(len: u32) -> Self {
2931        Self {
2932            len,
2933            kind: IndentKind::Space,
2934        }
2935    }
2936
2937    pub fn tab() -> Self {
2938        Self {
2939            len: 1,
2940            kind: IndentKind::Tab,
2941        }
2942    }
2943
2944    pub fn chars(&self) -> impl Iterator<Item = char> {
2945        iter::repeat(self.char()).take(self.len as usize)
2946    }
2947
2948    pub fn char(&self) -> char {
2949        match self.kind {
2950            IndentKind::Space => ' ',
2951            IndentKind::Tab => '\t',
2952        }
2953    }
2954
2955    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
2956        match direction {
2957            Ordering::Less => {
2958                if self.kind == size.kind && self.len >= size.len {
2959                    self.len -= size.len;
2960                }
2961            }
2962            Ordering::Equal => {}
2963            Ordering::Greater => {
2964                if self.len == 0 {
2965                    self = size;
2966                } else if self.kind == size.kind {
2967                    self.len += size.len;
2968                }
2969            }
2970        }
2971        self
2972    }
2973}
2974
2975impl Completion {
2976    pub fn sort_key(&self) -> (usize, &str) {
2977        let kind_key = match self.lsp_completion.kind {
2978            Some(lsp::CompletionItemKind::VARIABLE) => 0,
2979            _ => 1,
2980        };
2981        (kind_key, &self.label.text[self.label.filter_range.clone()])
2982    }
2983
2984    pub fn is_snippet(&self) -> bool {
2985        self.lsp_completion.insert_text_format == Some(lsp::InsertTextFormat::SNIPPET)
2986    }
2987}
2988
2989pub fn contiguous_ranges(
2990    values: impl Iterator<Item = u32>,
2991    max_len: usize,
2992) -> impl Iterator<Item = Range<u32>> {
2993    let mut values = values;
2994    let mut current_range: Option<Range<u32>> = None;
2995    std::iter::from_fn(move || loop {
2996        if let Some(value) = values.next() {
2997            if let Some(range) = &mut current_range {
2998                if value == range.end && range.len() < max_len {
2999                    range.end += 1;
3000                    continue;
3001                }
3002            }
3003
3004            let prev_range = current_range.clone();
3005            current_range = Some(value..(value + 1));
3006            if prev_range.is_some() {
3007                return prev_range;
3008            }
3009        } else {
3010            return current_range.take();
3011        }
3012    })
3013}
3014
3015pub fn char_kind(language: Option<&Arc<Language>>, c: char) -> CharKind {
3016    if c.is_whitespace() {
3017        return CharKind::Whitespace;
3018    } else if c.is_alphanumeric() || c == '_' {
3019        return CharKind::Word;
3020    }
3021    if let Some(language) = language {
3022        if language.config.word_characters.contains(&c) {
3023            return CharKind::Word;
3024        }
3025    }
3026    CharKind::Punctuation
3027}
3028
3029/// Find all of the ranges of whitespace that occur at the ends of lines
3030/// in the given rope.
3031///
3032/// This could also be done with a regex search, but this implementation
3033/// avoids copying text.
3034pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
3035    let mut ranges = Vec::new();
3036
3037    let mut offset = 0;
3038    let mut prev_chunk_trailing_whitespace_range = 0..0;
3039    for chunk in rope.chunks() {
3040        let mut prev_line_trailing_whitespace_range = 0..0;
3041        for (i, line) in chunk.split('\n').enumerate() {
3042            let line_end_offset = offset + line.len();
3043            let trimmed_line_len = line.trim_end_matches(|c| matches!(c, ' ' | '\t')).len();
3044            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
3045
3046            if i == 0 && trimmed_line_len == 0 {
3047                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
3048            }
3049            if !prev_line_trailing_whitespace_range.is_empty() {
3050                ranges.push(prev_line_trailing_whitespace_range);
3051            }
3052
3053            offset = line_end_offset + 1;
3054            prev_line_trailing_whitespace_range = trailing_whitespace_range;
3055        }
3056
3057        offset -= 1;
3058        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
3059    }
3060
3061    if !prev_chunk_trailing_whitespace_range.is_empty() {
3062        ranges.push(prev_chunk_trailing_whitespace_range);
3063    }
3064
3065    ranges
3066}