buffer.rs

   1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, Grammar, Language, LanguageRegistry,
   5};
   6use crate::{
   7    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   8    language_settings::{language_settings, LanguageSettings},
   9    outline::OutlineItem,
  10    syntax_map::{
  11        SyntaxLayer, SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxMapMatch,
  12        SyntaxMapMatches, SyntaxSnapshot, ToTreeSitterPoint,
  13    },
  14    task_context::RunnableRange,
  15    text_diff::text_diff,
  16    LanguageScope, Outline, OutlineConfig, RunnableCapture, RunnableTag, TextObject,
  17    TreeSitterOptions,
  18};
  19use anyhow::{anyhow, Context as _, Result};
  20use async_watch as watch;
  21use clock::Lamport;
  22pub use clock::ReplicaId;
  23use collections::HashMap;
  24use fs::MTime;
  25use futures::channel::oneshot;
  26use gpui::{
  27    AnyElement, App, AppContext as _, Context, Entity, EventEmitter, HighlightStyle, Pixels,
  28    SharedString, StyledText, Task, TaskLabel, TextStyle, Window,
  29};
  30use lsp::{LanguageServerId, NumberOrString};
  31use parking_lot::Mutex;
  32use schemars::JsonSchema;
  33use serde::{Deserialize, Serialize};
  34use serde_json::Value;
  35use settings::WorktreeId;
  36use smallvec::SmallVec;
  37use smol::future::yield_now;
  38use std::{
  39    any::Any,
  40    borrow::Cow,
  41    cell::Cell,
  42    cmp::{self, Ordering, Reverse},
  43    collections::{BTreeMap, BTreeSet},
  44    ffi::OsStr,
  45    fmt,
  46    future::Future,
  47    iter::{self, Iterator, Peekable},
  48    mem,
  49    num::NonZeroU32,
  50    ops::{Deref, DerefMut, Range},
  51    path::{Path, PathBuf},
  52    str,
  53    sync::{Arc, LazyLock},
  54    time::{Duration, Instant},
  55    vec,
  56};
  57use sum_tree::TreeMap;
  58use text::operation_queue::OperationQueue;
  59use text::*;
  60pub use text::{
  61    Anchor, Bias, Buffer as TextBuffer, BufferId, BufferSnapshot as TextBufferSnapshot, Edit,
  62    OffsetRangeExt, OffsetUtf16, Patch, Point, PointUtf16, Rope, Selection, SelectionGoal,
  63    Subscription, TextDimension, TextSummary, ToOffset, ToOffsetUtf16, ToPoint, ToPointUtf16,
  64    Transaction, TransactionId, Unclipped,
  65};
  66use theme::{ActiveTheme as _, SyntaxTheme};
  67#[cfg(any(test, feature = "test-support"))]
  68use util::RandomCharIter;
  69use util::{debug_panic, maybe, RangeExt};
  70
  71#[cfg(any(test, feature = "test-support"))]
  72pub use {tree_sitter_rust, tree_sitter_typescript};
  73
  74pub use lsp::DiagnosticSeverity;
  75
  76/// A label for the background task spawned by the buffer to compute
  77/// a diff against the contents of its file.
  78pub static BUFFER_DIFF_TASK: LazyLock<TaskLabel> = LazyLock::new(TaskLabel::new);
  79
  80/// Indicate whether a [`Buffer`] has permissions to edit.
  81#[derive(PartialEq, Clone, Copy, Debug)]
  82pub enum Capability {
  83    /// The buffer is a mutable replica.
  84    ReadWrite,
  85    /// The buffer is a read-only replica.
  86    ReadOnly,
  87}
  88
  89pub type BufferRow = u32;
  90
  91/// An in-memory representation of a source code file, including its text,
  92/// syntax trees, git status, and diagnostics.
  93pub struct Buffer {
  94    text: TextBuffer,
  95    branch_state: Option<BufferBranchState>,
  96    /// Filesystem state, `None` when there is no path.
  97    file: Option<Arc<dyn File>>,
  98    /// The mtime of the file when this buffer was last loaded from
  99    /// or saved to disk.
 100    saved_mtime: Option<MTime>,
 101    /// The version vector when this buffer was last loaded from
 102    /// or saved to disk.
 103    saved_version: clock::Global,
 104    preview_version: clock::Global,
 105    transaction_depth: usize,
 106    was_dirty_before_starting_transaction: Option<bool>,
 107    reload_task: Option<Task<Result<()>>>,
 108    language: Option<Arc<Language>>,
 109    autoindent_requests: Vec<Arc<AutoindentRequest>>,
 110    pending_autoindent: Option<Task<()>>,
 111    sync_parse_timeout: Duration,
 112    syntax_map: Mutex<SyntaxMap>,
 113    parsing_in_background: bool,
 114    parse_status: (watch::Sender<ParseStatus>, watch::Receiver<ParseStatus>),
 115    non_text_state_update_count: usize,
 116    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 117    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 118    diagnostics_timestamp: clock::Lamport,
 119    completion_triggers: BTreeSet<String>,
 120    completion_triggers_per_language_server: HashMap<LanguageServerId, BTreeSet<String>>,
 121    completion_triggers_timestamp: clock::Lamport,
 122    deferred_ops: OperationQueue<Operation>,
 123    capability: Capability,
 124    has_conflict: bool,
 125    /// Memoize calls to has_changes_since(saved_version).
 126    /// The contents of a cell are (self.version, has_changes) at the time of a last call.
 127    has_unsaved_edits: Cell<(clock::Global, bool)>,
 128    _subscriptions: Vec<gpui::Subscription>,
 129}
 130
 131#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 132pub enum ParseStatus {
 133    Idle,
 134    Parsing,
 135}
 136
 137struct BufferBranchState {
 138    base_buffer: Entity<Buffer>,
 139    merged_operations: Vec<Lamport>,
 140}
 141
 142/// An immutable, cheaply cloneable representation of a fixed
 143/// state of a buffer.
 144pub struct BufferSnapshot {
 145    pub text: text::BufferSnapshot,
 146    pub(crate) syntax: SyntaxSnapshot,
 147    file: Option<Arc<dyn File>>,
 148    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 149    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 150    language: Option<Arc<Language>>,
 151    non_text_state_update_count: usize,
 152}
 153
 154/// The kind and amount of indentation in a particular line. For now,
 155/// assumes that indentation is all the same character.
 156#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 157pub struct IndentSize {
 158    /// The number of bytes that comprise the indentation.
 159    pub len: u32,
 160    /// The kind of whitespace used for indentation.
 161    pub kind: IndentKind,
 162}
 163
 164/// A whitespace character that's used for indentation.
 165#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 166pub enum IndentKind {
 167    /// An ASCII space character.
 168    #[default]
 169    Space,
 170    /// An ASCII tab character.
 171    Tab,
 172}
 173
 174/// The shape of a selection cursor.
 175#[derive(Copy, Clone, Debug, Default, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 176#[serde(rename_all = "snake_case")]
 177pub enum CursorShape {
 178    /// A vertical bar
 179    #[default]
 180    Bar,
 181    /// A block that surrounds the following character
 182    Block,
 183    /// An underline that runs along the following character
 184    Underline,
 185    /// A box drawn around the following character
 186    Hollow,
 187}
 188
 189#[derive(Clone, Debug)]
 190struct SelectionSet {
 191    line_mode: bool,
 192    cursor_shape: CursorShape,
 193    selections: Arc<[Selection<Anchor>]>,
 194    lamport_timestamp: clock::Lamport,
 195}
 196
 197/// A diagnostic associated with a certain range of a buffer.
 198#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 199pub struct Diagnostic {
 200    /// The name of the service that produced this diagnostic.
 201    pub source: Option<String>,
 202    /// A machine-readable code that identifies this diagnostic.
 203    pub code: Option<NumberOrString>,
 204    /// Whether this diagnostic is a hint, warning, or error.
 205    pub severity: DiagnosticSeverity,
 206    /// The human-readable message associated with this diagnostic.
 207    pub message: String,
 208    /// An id that identifies the group to which this diagnostic belongs.
 209    ///
 210    /// When a language server produces a diagnostic with
 211    /// one or more associated diagnostics, those diagnostics are all
 212    /// assigned a single group ID.
 213    pub group_id: usize,
 214    /// Whether this diagnostic is the primary diagnostic for its group.
 215    ///
 216    /// In a given group, the primary diagnostic is the top-level diagnostic
 217    /// returned by the language server. The non-primary diagnostics are the
 218    /// associated diagnostics.
 219    pub is_primary: bool,
 220    /// Whether this diagnostic is considered to originate from an analysis of
 221    /// files on disk, as opposed to any unsaved buffer contents. This is a
 222    /// property of a given diagnostic source, and is configured for a given
 223    /// language server via the [`LspAdapter::disk_based_diagnostic_sources`](crate::LspAdapter::disk_based_diagnostic_sources) method
 224    /// for the language server.
 225    pub is_disk_based: bool,
 226    /// Whether this diagnostic marks unnecessary code.
 227    pub is_unnecessary: bool,
 228    /// Data from language server that produced this diagnostic. Passed back to the LS when we request code actions for this diagnostic.
 229    pub data: Option<Value>,
 230}
 231
 232/// An operation used to synchronize this buffer with its other replicas.
 233#[derive(Clone, Debug, PartialEq)]
 234pub enum Operation {
 235    /// A text operation.
 236    Buffer(text::Operation),
 237
 238    /// An update to the buffer's diagnostics.
 239    UpdateDiagnostics {
 240        /// The id of the language server that produced the new diagnostics.
 241        server_id: LanguageServerId,
 242        /// The diagnostics.
 243        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 244        /// The buffer's lamport timestamp.
 245        lamport_timestamp: clock::Lamport,
 246    },
 247
 248    /// An update to the most recent selections in this buffer.
 249    UpdateSelections {
 250        /// The selections.
 251        selections: Arc<[Selection<Anchor>]>,
 252        /// The buffer's lamport timestamp.
 253        lamport_timestamp: clock::Lamport,
 254        /// Whether the selections are in 'line mode'.
 255        line_mode: bool,
 256        /// The [`CursorShape`] associated with these selections.
 257        cursor_shape: CursorShape,
 258    },
 259
 260    /// An update to the characters that should trigger autocompletion
 261    /// for this buffer.
 262    UpdateCompletionTriggers {
 263        /// The characters that trigger autocompletion.
 264        triggers: Vec<String>,
 265        /// The buffer's lamport timestamp.
 266        lamport_timestamp: clock::Lamport,
 267        /// The language server ID.
 268        server_id: LanguageServerId,
 269    },
 270}
 271
 272/// An event that occurs in a buffer.
 273#[derive(Clone, Debug, PartialEq)]
 274pub enum BufferEvent {
 275    /// The buffer was changed in a way that must be
 276    /// propagated to its other replicas.
 277    Operation {
 278        operation: Operation,
 279        is_local: bool,
 280    },
 281    /// The buffer was edited.
 282    Edited,
 283    /// The buffer's `dirty` bit changed.
 284    DirtyChanged,
 285    /// The buffer was saved.
 286    Saved,
 287    /// The buffer's file was changed on disk.
 288    FileHandleChanged,
 289    /// The buffer was reloaded.
 290    Reloaded,
 291    /// The buffer is in need of a reload
 292    ReloadNeeded,
 293    /// The buffer's language was changed.
 294    LanguageChanged,
 295    /// The buffer's syntax trees were updated.
 296    Reparsed,
 297    /// The buffer's diagnostics were updated.
 298    DiagnosticsUpdated,
 299    /// The buffer gained or lost editing capabilities.
 300    CapabilityChanged,
 301    /// The buffer was explicitly requested to close.
 302    Closed,
 303    /// The buffer was discarded when closing.
 304    Discarded,
 305}
 306
 307/// The file associated with a buffer.
 308pub trait File: Send + Sync {
 309    /// Returns the [`LocalFile`] associated with this file, if the
 310    /// file is local.
 311    fn as_local(&self) -> Option<&dyn LocalFile>;
 312
 313    /// Returns whether this file is local.
 314    fn is_local(&self) -> bool {
 315        self.as_local().is_some()
 316    }
 317
 318    /// Returns whether the file is new, exists in storage, or has been deleted. Includes metadata
 319    /// only available in some states, such as modification time.
 320    fn disk_state(&self) -> DiskState;
 321
 322    /// Returns the path of this file relative to the worktree's root directory.
 323    fn path(&self) -> &Arc<Path>;
 324
 325    /// Returns the path of this file relative to the worktree's parent directory (this means it
 326    /// includes the name of the worktree's root folder).
 327    fn full_path(&self, cx: &App) -> PathBuf;
 328
 329    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 330    /// of its worktree, then this method will return the name of the worktree itself.
 331    fn file_name<'a>(&'a self, cx: &'a App) -> &'a OsStr;
 332
 333    /// Returns the id of the worktree to which this file belongs.
 334    ///
 335    /// This is needed for looking up project-specific settings.
 336    fn worktree_id(&self, cx: &App) -> WorktreeId;
 337
 338    /// Converts this file into an [`Any`] trait object.
 339    fn as_any(&self) -> &dyn Any;
 340
 341    /// Converts this file into a protobuf message.
 342    fn to_proto(&self, cx: &App) -> rpc::proto::File;
 343
 344    /// Return whether Zed considers this to be a private file.
 345    fn is_private(&self) -> bool;
 346}
 347
 348/// The file's storage status - whether it's stored (`Present`), and if so when it was last
 349/// modified. In the case where the file is not stored, it can be either `New` or `Deleted`. In the
 350/// UI these two states are distinguished. For example, the buffer tab does not display a deletion
 351/// indicator for new files.
 352#[derive(Copy, Clone, Debug, PartialEq)]
 353pub enum DiskState {
 354    /// File created in Zed that has not been saved.
 355    New,
 356    /// File present on the filesystem.
 357    Present { mtime: MTime },
 358    /// Deleted file that was previously present.
 359    Deleted,
 360}
 361
 362impl DiskState {
 363    /// Returns the file's last known modification time on disk.
 364    pub fn mtime(self) -> Option<MTime> {
 365        match self {
 366            DiskState::New => None,
 367            DiskState::Present { mtime } => Some(mtime),
 368            DiskState::Deleted => None,
 369        }
 370    }
 371
 372    pub fn exists(&self) -> bool {
 373        match self {
 374            DiskState::New => false,
 375            DiskState::Present { .. } => true,
 376            DiskState::Deleted => false,
 377        }
 378    }
 379}
 380
 381/// The file associated with a buffer, in the case where the file is on the local disk.
 382pub trait LocalFile: File {
 383    /// Returns the absolute path of this file
 384    fn abs_path(&self, cx: &App) -> PathBuf;
 385
 386    /// Loads the file contents from disk and returns them as a UTF-8 encoded string.
 387    fn load(&self, cx: &App) -> Task<Result<String>>;
 388
 389    /// Loads the file's contents from disk.
 390    fn load_bytes(&self, cx: &App) -> Task<Result<Vec<u8>>>;
 391}
 392
 393/// The auto-indent behavior associated with an editing operation.
 394/// For some editing operations, each affected line of text has its
 395/// indentation recomputed. For other operations, the entire block
 396/// of edited text is adjusted uniformly.
 397#[derive(Clone, Debug)]
 398pub enum AutoindentMode {
 399    /// Indent each line of inserted text.
 400    EachLine,
 401    /// Apply the same indentation adjustment to all of the lines
 402    /// in a given insertion.
 403    Block {
 404        /// The original start column of each insertion, if it was
 405        /// copied from elsewhere.
 406        ///
 407        /// Knowing this start column makes it possible to preserve the
 408        /// relative indentation of every line in the insertion from
 409        /// when it was copied.
 410        ///
 411        /// If the start column is `a`, and the first line of insertion
 412        /// is then auto-indented to column `b`, then every other line of
 413        /// the insertion will be auto-indented to column `b - a`
 414        original_start_columns: Vec<u32>,
 415    },
 416}
 417
 418#[derive(Clone)]
 419struct AutoindentRequest {
 420    before_edit: BufferSnapshot,
 421    entries: Vec<AutoindentRequestEntry>,
 422    is_block_mode: bool,
 423    ignore_empty_lines: bool,
 424}
 425
 426#[derive(Debug, Clone)]
 427struct AutoindentRequestEntry {
 428    /// A range of the buffer whose indentation should be adjusted.
 429    range: Range<Anchor>,
 430    /// Whether or not these lines should be considered brand new, for the
 431    /// purpose of auto-indent. When text is not new, its indentation will
 432    /// only be adjusted if the suggested indentation level has *changed*
 433    /// since the edit was made.
 434    first_line_is_new: bool,
 435    indent_size: IndentSize,
 436    original_indent_column: Option<u32>,
 437}
 438
 439#[derive(Debug)]
 440struct IndentSuggestion {
 441    basis_row: u32,
 442    delta: Ordering,
 443    within_error: bool,
 444}
 445
 446struct BufferChunkHighlights<'a> {
 447    captures: SyntaxMapCaptures<'a>,
 448    next_capture: Option<SyntaxMapCapture<'a>>,
 449    stack: Vec<(usize, HighlightId)>,
 450    highlight_maps: Vec<HighlightMap>,
 451}
 452
 453/// An iterator that yields chunks of a buffer's text, along with their
 454/// syntax highlights and diagnostic status.
 455pub struct BufferChunks<'a> {
 456    buffer_snapshot: Option<&'a BufferSnapshot>,
 457    range: Range<usize>,
 458    chunks: text::Chunks<'a>,
 459    diagnostic_endpoints: Option<Peekable<vec::IntoIter<DiagnosticEndpoint>>>,
 460    error_depth: usize,
 461    warning_depth: usize,
 462    information_depth: usize,
 463    hint_depth: usize,
 464    unnecessary_depth: usize,
 465    highlights: Option<BufferChunkHighlights<'a>>,
 466}
 467
 468/// A chunk of a buffer's text, along with its syntax highlight and
 469/// diagnostic status.
 470#[derive(Clone, Debug, Default)]
 471pub struct Chunk<'a> {
 472    /// The text of the chunk.
 473    pub text: &'a str,
 474    /// The syntax highlighting style of the chunk.
 475    pub syntax_highlight_id: Option<HighlightId>,
 476    /// The highlight style that has been applied to this chunk in
 477    /// the editor.
 478    pub highlight_style: Option<HighlightStyle>,
 479    /// The severity of diagnostic associated with this chunk, if any.
 480    pub diagnostic_severity: Option<DiagnosticSeverity>,
 481    /// Whether this chunk of text is marked as unnecessary.
 482    pub is_unnecessary: bool,
 483    /// Whether this chunk of text was originally a tab character.
 484    pub is_tab: bool,
 485    /// An optional recipe for how the chunk should be presented.
 486    pub renderer: Option<ChunkRenderer>,
 487}
 488
 489/// A recipe for how the chunk should be presented.
 490#[derive(Clone)]
 491pub struct ChunkRenderer {
 492    /// creates a custom element to represent this chunk.
 493    pub render: Arc<dyn Send + Sync + Fn(&mut ChunkRendererContext) -> AnyElement>,
 494    /// If true, the element is constrained to the shaped width of the text.
 495    pub constrain_width: bool,
 496}
 497
 498pub struct ChunkRendererContext<'a, 'b> {
 499    pub window: &'a mut Window,
 500    pub context: &'b mut App,
 501    pub max_width: Pixels,
 502}
 503
 504impl fmt::Debug for ChunkRenderer {
 505    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 506        f.debug_struct("ChunkRenderer")
 507            .field("constrain_width", &self.constrain_width)
 508            .finish()
 509    }
 510}
 511
 512impl Deref for ChunkRendererContext<'_, '_> {
 513    type Target = App;
 514
 515    fn deref(&self) -> &Self::Target {
 516        self.context
 517    }
 518}
 519
 520impl DerefMut for ChunkRendererContext<'_, '_> {
 521    fn deref_mut(&mut self) -> &mut Self::Target {
 522        self.context
 523    }
 524}
 525
 526/// A set of edits to a given version of a buffer, computed asynchronously.
 527#[derive(Debug)]
 528pub struct Diff {
 529    pub(crate) base_version: clock::Global,
 530    line_ending: LineEnding,
 531    pub edits: Vec<(Range<usize>, Arc<str>)>,
 532}
 533
 534#[derive(Clone, Copy)]
 535pub(crate) struct DiagnosticEndpoint {
 536    offset: usize,
 537    is_start: bool,
 538    severity: DiagnosticSeverity,
 539    is_unnecessary: bool,
 540}
 541
 542/// A class of characters, used for characterizing a run of text.
 543#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 544pub enum CharKind {
 545    /// Whitespace.
 546    Whitespace,
 547    /// Punctuation.
 548    Punctuation,
 549    /// Word.
 550    Word,
 551}
 552
 553/// A runnable is a set of data about a region that could be resolved into a task
 554pub struct Runnable {
 555    pub tags: SmallVec<[RunnableTag; 1]>,
 556    pub language: Arc<Language>,
 557    pub buffer: BufferId,
 558}
 559
 560#[derive(Default, Clone, Debug)]
 561pub struct HighlightedText {
 562    pub text: SharedString,
 563    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 564}
 565
 566#[derive(Default, Debug)]
 567struct HighlightedTextBuilder {
 568    pub text: String,
 569    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 570}
 571
 572impl HighlightedText {
 573    pub fn from_buffer_range<T: ToOffset>(
 574        range: Range<T>,
 575        snapshot: &text::BufferSnapshot,
 576        syntax_snapshot: &SyntaxSnapshot,
 577        override_style: Option<HighlightStyle>,
 578        syntax_theme: &SyntaxTheme,
 579    ) -> Self {
 580        let mut highlighted_text = HighlightedTextBuilder::default();
 581        highlighted_text.add_text_from_buffer_range(
 582            range,
 583            snapshot,
 584            syntax_snapshot,
 585            override_style,
 586            syntax_theme,
 587        );
 588        highlighted_text.build()
 589    }
 590
 591    pub fn to_styled_text(&self, default_style: &TextStyle) -> StyledText {
 592        gpui::StyledText::new(self.text.clone())
 593            .with_default_highlights(default_style, self.highlights.iter().cloned())
 594    }
 595
 596    /// Returns the first line without leading whitespace unless highlighted
 597    /// and a boolean indicating if there are more lines after
 598    pub fn first_line_preview(self) -> (Self, bool) {
 599        let newline_ix = self.text.find('\n').unwrap_or(self.text.len());
 600        let first_line = &self.text[..newline_ix];
 601
 602        // Trim leading whitespace, unless an edit starts prior to it.
 603        let mut preview_start_ix = first_line.len() - first_line.trim_start().len();
 604        if let Some((first_highlight_range, _)) = self.highlights.first() {
 605            preview_start_ix = preview_start_ix.min(first_highlight_range.start);
 606        }
 607
 608        let preview_text = &first_line[preview_start_ix..];
 609        let preview_highlights = self
 610            .highlights
 611            .into_iter()
 612            .take_while(|(range, _)| range.start < newline_ix)
 613            .filter_map(|(mut range, highlight)| {
 614                range.start = range.start.saturating_sub(preview_start_ix);
 615                range.end = range.end.saturating_sub(preview_start_ix).min(newline_ix);
 616                if range.is_empty() {
 617                    None
 618                } else {
 619                    Some((range, highlight))
 620                }
 621            });
 622
 623        let preview = Self {
 624            text: SharedString::new(preview_text),
 625            highlights: preview_highlights.collect(),
 626        };
 627
 628        (preview, self.text.len() > newline_ix)
 629    }
 630}
 631
 632impl HighlightedTextBuilder {
 633    pub fn build(self) -> HighlightedText {
 634        HighlightedText {
 635            text: self.text.into(),
 636            highlights: self.highlights,
 637        }
 638    }
 639
 640    pub fn add_text_from_buffer_range<T: ToOffset>(
 641        &mut self,
 642        range: Range<T>,
 643        snapshot: &text::BufferSnapshot,
 644        syntax_snapshot: &SyntaxSnapshot,
 645        override_style: Option<HighlightStyle>,
 646        syntax_theme: &SyntaxTheme,
 647    ) {
 648        let range = range.to_offset(snapshot);
 649        for chunk in Self::highlighted_chunks(range, snapshot, syntax_snapshot) {
 650            let start = self.text.len();
 651            self.text.push_str(chunk.text);
 652            let end = self.text.len();
 653
 654            if let Some(mut highlight_style) = chunk
 655                .syntax_highlight_id
 656                .and_then(|id| id.style(syntax_theme))
 657            {
 658                if let Some(override_style) = override_style {
 659                    highlight_style.highlight(override_style);
 660                }
 661                self.highlights.push((start..end, highlight_style));
 662            } else if let Some(override_style) = override_style {
 663                self.highlights.push((start..end, override_style));
 664            }
 665        }
 666    }
 667
 668    fn highlighted_chunks<'a>(
 669        range: Range<usize>,
 670        snapshot: &'a text::BufferSnapshot,
 671        syntax_snapshot: &'a SyntaxSnapshot,
 672    ) -> BufferChunks<'a> {
 673        let captures = syntax_snapshot.captures(range.clone(), snapshot, |grammar| {
 674            grammar.highlights_query.as_ref()
 675        });
 676
 677        let highlight_maps = captures
 678            .grammars()
 679            .iter()
 680            .map(|grammar| grammar.highlight_map())
 681            .collect();
 682
 683        BufferChunks::new(
 684            snapshot.as_rope(),
 685            range,
 686            Some((captures, highlight_maps)),
 687            false,
 688            None,
 689        )
 690    }
 691}
 692
 693#[derive(Clone)]
 694pub struct EditPreview {
 695    old_snapshot: text::BufferSnapshot,
 696    applied_edits_snapshot: text::BufferSnapshot,
 697    syntax_snapshot: SyntaxSnapshot,
 698}
 699
 700impl EditPreview {
 701    pub fn highlight_edits(
 702        &self,
 703        current_snapshot: &BufferSnapshot,
 704        edits: &[(Range<Anchor>, String)],
 705        include_deletions: bool,
 706        cx: &App,
 707    ) -> HighlightedText {
 708        let Some(visible_range_in_preview_snapshot) = self.compute_visible_range(edits) else {
 709            return HighlightedText::default();
 710        };
 711
 712        let mut highlighted_text = HighlightedTextBuilder::default();
 713
 714        let mut offset_in_preview_snapshot = visible_range_in_preview_snapshot.start;
 715
 716        let insertion_highlight_style = HighlightStyle {
 717            background_color: Some(cx.theme().status().created_background),
 718            ..Default::default()
 719        };
 720        let deletion_highlight_style = HighlightStyle {
 721            background_color: Some(cx.theme().status().deleted_background),
 722            ..Default::default()
 723        };
 724        let syntax_theme = cx.theme().syntax();
 725
 726        for (range, edit_text) in edits {
 727            let edit_new_end_in_preview_snapshot = range
 728                .end
 729                .bias_right(&self.old_snapshot)
 730                .to_offset(&self.applied_edits_snapshot);
 731            let edit_start_in_preview_snapshot = edit_new_end_in_preview_snapshot - edit_text.len();
 732
 733            let unchanged_range_in_preview_snapshot =
 734                offset_in_preview_snapshot..edit_start_in_preview_snapshot;
 735            if !unchanged_range_in_preview_snapshot.is_empty() {
 736                highlighted_text.add_text_from_buffer_range(
 737                    unchanged_range_in_preview_snapshot,
 738                    &self.applied_edits_snapshot,
 739                    &self.syntax_snapshot,
 740                    None,
 741                    &syntax_theme,
 742                );
 743            }
 744
 745            let range_in_current_snapshot = range.to_offset(current_snapshot);
 746            if include_deletions && !range_in_current_snapshot.is_empty() {
 747                highlighted_text.add_text_from_buffer_range(
 748                    range_in_current_snapshot,
 749                    &current_snapshot.text,
 750                    &current_snapshot.syntax,
 751                    Some(deletion_highlight_style),
 752                    &syntax_theme,
 753                );
 754            }
 755
 756            if !edit_text.is_empty() {
 757                highlighted_text.add_text_from_buffer_range(
 758                    edit_start_in_preview_snapshot..edit_new_end_in_preview_snapshot,
 759                    &self.applied_edits_snapshot,
 760                    &self.syntax_snapshot,
 761                    Some(insertion_highlight_style),
 762                    &syntax_theme,
 763                );
 764            }
 765
 766            offset_in_preview_snapshot = edit_new_end_in_preview_snapshot;
 767        }
 768
 769        highlighted_text.add_text_from_buffer_range(
 770            offset_in_preview_snapshot..visible_range_in_preview_snapshot.end,
 771            &self.applied_edits_snapshot,
 772            &self.syntax_snapshot,
 773            None,
 774            &syntax_theme,
 775        );
 776
 777        highlighted_text.build()
 778    }
 779
 780    fn compute_visible_range(&self, edits: &[(Range<Anchor>, String)]) -> Option<Range<usize>> {
 781        let (first, _) = edits.first()?;
 782        let (last, _) = edits.last()?;
 783
 784        let start = first
 785            .start
 786            .bias_left(&self.old_snapshot)
 787            .to_point(&self.applied_edits_snapshot);
 788        let end = last
 789            .end
 790            .bias_right(&self.old_snapshot)
 791            .to_point(&self.applied_edits_snapshot);
 792
 793        // Ensure that the first line of the first edit and the last line of the last edit are always fully visible
 794        let range = Point::new(start.row, 0)
 795            ..Point::new(end.row, self.applied_edits_snapshot.line_len(end.row));
 796
 797        Some(range.to_offset(&self.applied_edits_snapshot))
 798    }
 799}
 800
 801#[derive(Clone, Debug, PartialEq, Eq)]
 802pub struct BracketMatch {
 803    pub open_range: Range<usize>,
 804    pub close_range: Range<usize>,
 805    pub newline_only: bool,
 806}
 807
 808impl Buffer {
 809    /// Create a new buffer with the given base text.
 810    pub fn local<T: Into<String>>(base_text: T, cx: &Context<Self>) -> Self {
 811        Self::build(
 812            TextBuffer::new(0, cx.entity_id().as_non_zero_u64().into(), base_text.into()),
 813            None,
 814            Capability::ReadWrite,
 815        )
 816    }
 817
 818    /// Create a new buffer with the given base text that has proper line endings and other normalization applied.
 819    pub fn local_normalized(
 820        base_text_normalized: Rope,
 821        line_ending: LineEnding,
 822        cx: &Context<Self>,
 823    ) -> Self {
 824        Self::build(
 825            TextBuffer::new_normalized(
 826                0,
 827                cx.entity_id().as_non_zero_u64().into(),
 828                line_ending,
 829                base_text_normalized,
 830            ),
 831            None,
 832            Capability::ReadWrite,
 833        )
 834    }
 835
 836    /// Create a new buffer that is a replica of a remote buffer.
 837    pub fn remote(
 838        remote_id: BufferId,
 839        replica_id: ReplicaId,
 840        capability: Capability,
 841        base_text: impl Into<String>,
 842    ) -> Self {
 843        Self::build(
 844            TextBuffer::new(replica_id, remote_id, base_text.into()),
 845            None,
 846            capability,
 847        )
 848    }
 849
 850    /// Create a new buffer that is a replica of a remote buffer, populating its
 851    /// state from the given protobuf message.
 852    pub fn from_proto(
 853        replica_id: ReplicaId,
 854        capability: Capability,
 855        message: proto::BufferState,
 856        file: Option<Arc<dyn File>>,
 857    ) -> Result<Self> {
 858        let buffer_id = BufferId::new(message.id)
 859            .with_context(|| anyhow!("Could not deserialize buffer_id"))?;
 860        let buffer = TextBuffer::new(replica_id, buffer_id, message.base_text);
 861        let mut this = Self::build(buffer, file, capability);
 862        this.text.set_line_ending(proto::deserialize_line_ending(
 863            rpc::proto::LineEnding::from_i32(message.line_ending)
 864                .ok_or_else(|| anyhow!("missing line_ending"))?,
 865        ));
 866        this.saved_version = proto::deserialize_version(&message.saved_version);
 867        this.saved_mtime = message.saved_mtime.map(|time| time.into());
 868        Ok(this)
 869    }
 870
 871    /// Serialize the buffer's state to a protobuf message.
 872    pub fn to_proto(&self, cx: &App) -> proto::BufferState {
 873        proto::BufferState {
 874            id: self.remote_id().into(),
 875            file: self.file.as_ref().map(|f| f.to_proto(cx)),
 876            base_text: self.base_text().to_string(),
 877            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 878            saved_version: proto::serialize_version(&self.saved_version),
 879            saved_mtime: self.saved_mtime.map(|time| time.into()),
 880        }
 881    }
 882
 883    /// Serialize as protobufs all of the changes to the buffer since the given version.
 884    pub fn serialize_ops(
 885        &self,
 886        since: Option<clock::Global>,
 887        cx: &App,
 888    ) -> Task<Vec<proto::Operation>> {
 889        let mut operations = Vec::new();
 890        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 891
 892        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 893            proto::serialize_operation(&Operation::UpdateSelections {
 894                selections: set.selections.clone(),
 895                lamport_timestamp: set.lamport_timestamp,
 896                line_mode: set.line_mode,
 897                cursor_shape: set.cursor_shape,
 898            })
 899        }));
 900
 901        for (server_id, diagnostics) in &self.diagnostics {
 902            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 903                lamport_timestamp: self.diagnostics_timestamp,
 904                server_id: *server_id,
 905                diagnostics: diagnostics.iter().cloned().collect(),
 906            }));
 907        }
 908
 909        for (server_id, completions) in &self.completion_triggers_per_language_server {
 910            operations.push(proto::serialize_operation(
 911                &Operation::UpdateCompletionTriggers {
 912                    triggers: completions.iter().cloned().collect(),
 913                    lamport_timestamp: self.completion_triggers_timestamp,
 914                    server_id: *server_id,
 915                },
 916            ));
 917        }
 918
 919        let text_operations = self.text.operations().clone();
 920        cx.background_spawn(async move {
 921            let since = since.unwrap_or_default();
 922            operations.extend(
 923                text_operations
 924                    .iter()
 925                    .filter(|(_, op)| !since.observed(op.timestamp()))
 926                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 927            );
 928            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 929            operations
 930        })
 931    }
 932
 933    /// Assign a language to the buffer, returning the buffer.
 934    pub fn with_language(mut self, language: Arc<Language>, cx: &mut Context<Self>) -> Self {
 935        self.set_language(Some(language), cx);
 936        self
 937    }
 938
 939    /// Returns the [`Capability`] of this buffer.
 940    pub fn capability(&self) -> Capability {
 941        self.capability
 942    }
 943
 944    /// Whether this buffer can only be read.
 945    pub fn read_only(&self) -> bool {
 946        self.capability == Capability::ReadOnly
 947    }
 948
 949    /// Builds a [`Buffer`] with the given underlying [`TextBuffer`], diff base, [`File`] and [`Capability`].
 950    pub fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>, capability: Capability) -> Self {
 951        let saved_mtime = file.as_ref().and_then(|file| file.disk_state().mtime());
 952        let snapshot = buffer.snapshot();
 953        let syntax_map = Mutex::new(SyntaxMap::new(&snapshot));
 954        Self {
 955            saved_mtime,
 956            saved_version: buffer.version(),
 957            preview_version: buffer.version(),
 958            reload_task: None,
 959            transaction_depth: 0,
 960            was_dirty_before_starting_transaction: None,
 961            has_unsaved_edits: Cell::new((buffer.version(), false)),
 962            text: buffer,
 963            branch_state: None,
 964            file,
 965            capability,
 966            syntax_map,
 967            parsing_in_background: false,
 968            non_text_state_update_count: 0,
 969            sync_parse_timeout: Duration::from_millis(1),
 970            parse_status: async_watch::channel(ParseStatus::Idle),
 971            autoindent_requests: Default::default(),
 972            pending_autoindent: Default::default(),
 973            language: None,
 974            remote_selections: Default::default(),
 975            diagnostics: Default::default(),
 976            diagnostics_timestamp: Default::default(),
 977            completion_triggers: Default::default(),
 978            completion_triggers_per_language_server: Default::default(),
 979            completion_triggers_timestamp: Default::default(),
 980            deferred_ops: OperationQueue::new(),
 981            has_conflict: false,
 982            _subscriptions: Vec::new(),
 983        }
 984    }
 985
 986    pub fn build_snapshot(
 987        text: Rope,
 988        language: Option<Arc<Language>>,
 989        language_registry: Option<Arc<LanguageRegistry>>,
 990        cx: &mut App,
 991    ) -> impl Future<Output = BufferSnapshot> {
 992        let entity_id = cx.reserve_entity::<Self>().entity_id();
 993        let buffer_id = entity_id.as_non_zero_u64().into();
 994        async move {
 995            let text =
 996                TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
 997            let mut syntax = SyntaxMap::new(&text).snapshot();
 998            if let Some(language) = language.clone() {
 999                let text = text.clone();
1000                let language = language.clone();
1001                let language_registry = language_registry.clone();
1002                syntax.reparse(&text, language_registry, language);
1003            }
1004            BufferSnapshot {
1005                text,
1006                syntax,
1007                file: None,
1008                diagnostics: Default::default(),
1009                remote_selections: Default::default(),
1010                language,
1011                non_text_state_update_count: 0,
1012            }
1013        }
1014    }
1015
1016    pub fn build_empty_snapshot(cx: &mut App) -> BufferSnapshot {
1017        let entity_id = cx.reserve_entity::<Self>().entity_id();
1018        let buffer_id = entity_id.as_non_zero_u64().into();
1019        let text =
1020            TextBuffer::new_normalized(0, buffer_id, Default::default(), Rope::new()).snapshot();
1021        let syntax = SyntaxMap::new(&text).snapshot();
1022        BufferSnapshot {
1023            text,
1024            syntax,
1025            file: None,
1026            diagnostics: Default::default(),
1027            remote_selections: Default::default(),
1028            language: None,
1029            non_text_state_update_count: 0,
1030        }
1031    }
1032
1033    #[cfg(any(test, feature = "test-support"))]
1034    pub fn build_snapshot_sync(
1035        text: Rope,
1036        language: Option<Arc<Language>>,
1037        language_registry: Option<Arc<LanguageRegistry>>,
1038        cx: &mut App,
1039    ) -> BufferSnapshot {
1040        let entity_id = cx.reserve_entity::<Self>().entity_id();
1041        let buffer_id = entity_id.as_non_zero_u64().into();
1042        let text = TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
1043        let mut syntax = SyntaxMap::new(&text).snapshot();
1044        if let Some(language) = language.clone() {
1045            let text = text.clone();
1046            let language = language.clone();
1047            let language_registry = language_registry.clone();
1048            syntax.reparse(&text, language_registry, language);
1049        }
1050        BufferSnapshot {
1051            text,
1052            syntax,
1053            file: None,
1054            diagnostics: Default::default(),
1055            remote_selections: Default::default(),
1056            language,
1057            non_text_state_update_count: 0,
1058        }
1059    }
1060
1061    /// Retrieve a snapshot of the buffer's current state. This is computationally
1062    /// cheap, and allows reading from the buffer on a background thread.
1063    pub fn snapshot(&self) -> BufferSnapshot {
1064        let text = self.text.snapshot();
1065        let mut syntax_map = self.syntax_map.lock();
1066        syntax_map.interpolate(&text);
1067        let syntax = syntax_map.snapshot();
1068
1069        BufferSnapshot {
1070            text,
1071            syntax,
1072            file: self.file.clone(),
1073            remote_selections: self.remote_selections.clone(),
1074            diagnostics: self.diagnostics.clone(),
1075            language: self.language.clone(),
1076            non_text_state_update_count: self.non_text_state_update_count,
1077        }
1078    }
1079
1080    pub fn branch(&mut self, cx: &mut Context<Self>) -> Entity<Self> {
1081        let this = cx.entity();
1082        cx.new(|cx| {
1083            let mut branch = Self {
1084                branch_state: Some(BufferBranchState {
1085                    base_buffer: this.clone(),
1086                    merged_operations: Default::default(),
1087                }),
1088                language: self.language.clone(),
1089                has_conflict: self.has_conflict,
1090                has_unsaved_edits: Cell::new(self.has_unsaved_edits.get_mut().clone()),
1091                _subscriptions: vec![cx.subscribe(&this, Self::on_base_buffer_event)],
1092                ..Self::build(self.text.branch(), self.file.clone(), self.capability())
1093            };
1094            if let Some(language_registry) = self.language_registry() {
1095                branch.set_language_registry(language_registry);
1096            }
1097
1098            // Reparse the branch buffer so that we get syntax highlighting immediately.
1099            branch.reparse(cx);
1100
1101            branch
1102        })
1103    }
1104
1105    pub fn preview_edits(
1106        &self,
1107        edits: Arc<[(Range<Anchor>, String)]>,
1108        cx: &App,
1109    ) -> Task<EditPreview> {
1110        let registry = self.language_registry();
1111        let language = self.language().cloned();
1112        let old_snapshot = self.text.snapshot();
1113        let mut branch_buffer = self.text.branch();
1114        let mut syntax_snapshot = self.syntax_map.lock().snapshot();
1115        cx.background_spawn(async move {
1116            if !edits.is_empty() {
1117                if let Some(language) = language.clone() {
1118                    syntax_snapshot.reparse(&old_snapshot, registry.clone(), language);
1119                }
1120
1121                branch_buffer.edit(edits.iter().cloned());
1122                let snapshot = branch_buffer.snapshot();
1123                syntax_snapshot.interpolate(&snapshot);
1124
1125                if let Some(language) = language {
1126                    syntax_snapshot.reparse(&snapshot, registry, language);
1127                }
1128            }
1129            EditPreview {
1130                old_snapshot,
1131                applied_edits_snapshot: branch_buffer.snapshot(),
1132                syntax_snapshot,
1133            }
1134        })
1135    }
1136
1137    /// Applies all of the changes in this buffer that intersect any of the
1138    /// given `ranges` to its base buffer.
1139    ///
1140    /// If `ranges` is empty, then all changes will be applied. This buffer must
1141    /// be a branch buffer to call this method.
1142    pub fn merge_into_base(&mut self, ranges: Vec<Range<usize>>, cx: &mut Context<Self>) {
1143        let Some(base_buffer) = self.base_buffer() else {
1144            debug_panic!("not a branch buffer");
1145            return;
1146        };
1147
1148        let mut ranges = if ranges.is_empty() {
1149            &[0..usize::MAX]
1150        } else {
1151            ranges.as_slice()
1152        }
1153        .into_iter()
1154        .peekable();
1155
1156        let mut edits = Vec::new();
1157        for edit in self.edits_since::<usize>(&base_buffer.read(cx).version()) {
1158            let mut is_included = false;
1159            while let Some(range) = ranges.peek() {
1160                if range.end < edit.new.start {
1161                    ranges.next().unwrap();
1162                } else {
1163                    if range.start <= edit.new.end {
1164                        is_included = true;
1165                    }
1166                    break;
1167                }
1168            }
1169
1170            if is_included {
1171                edits.push((
1172                    edit.old.clone(),
1173                    self.text_for_range(edit.new.clone()).collect::<String>(),
1174                ));
1175            }
1176        }
1177
1178        let operation = base_buffer.update(cx, |base_buffer, cx| {
1179            // cx.emit(BufferEvent::DiffBaseChanged);
1180            base_buffer.edit(edits, None, cx)
1181        });
1182
1183        if let Some(operation) = operation {
1184            if let Some(BufferBranchState {
1185                merged_operations, ..
1186            }) = &mut self.branch_state
1187            {
1188                merged_operations.push(operation);
1189            }
1190        }
1191    }
1192
1193    fn on_base_buffer_event(
1194        &mut self,
1195        _: Entity<Buffer>,
1196        event: &BufferEvent,
1197        cx: &mut Context<Self>,
1198    ) {
1199        let BufferEvent::Operation { operation, .. } = event else {
1200            return;
1201        };
1202        let Some(BufferBranchState {
1203            merged_operations, ..
1204        }) = &mut self.branch_state
1205        else {
1206            return;
1207        };
1208
1209        let mut operation_to_undo = None;
1210        if let Operation::Buffer(text::Operation::Edit(operation)) = &operation {
1211            if let Ok(ix) = merged_operations.binary_search(&operation.timestamp) {
1212                merged_operations.remove(ix);
1213                operation_to_undo = Some(operation.timestamp);
1214            }
1215        }
1216
1217        self.apply_ops([operation.clone()], cx);
1218
1219        if let Some(timestamp) = operation_to_undo {
1220            let counts = [(timestamp, u32::MAX)].into_iter().collect();
1221            self.undo_operations(counts, cx);
1222        }
1223    }
1224
1225    #[cfg(test)]
1226    pub(crate) fn as_text_snapshot(&self) -> &text::BufferSnapshot {
1227        &self.text
1228    }
1229
1230    /// Retrieve a snapshot of the buffer's raw text, without any
1231    /// language-related state like the syntax tree or diagnostics.
1232    pub fn text_snapshot(&self) -> text::BufferSnapshot {
1233        self.text.snapshot()
1234    }
1235
1236    /// The file associated with the buffer, if any.
1237    pub fn file(&self) -> Option<&Arc<dyn File>> {
1238        self.file.as_ref()
1239    }
1240
1241    /// The version of the buffer that was last saved or reloaded from disk.
1242    pub fn saved_version(&self) -> &clock::Global {
1243        &self.saved_version
1244    }
1245
1246    /// The mtime of the buffer's file when the buffer was last saved or reloaded from disk.
1247    pub fn saved_mtime(&self) -> Option<MTime> {
1248        self.saved_mtime
1249    }
1250
1251    /// Assign a language to the buffer.
1252    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut Context<Self>) {
1253        self.non_text_state_update_count += 1;
1254        self.syntax_map.lock().clear(&self.text);
1255        self.language = language;
1256        self.reparse(cx);
1257        cx.emit(BufferEvent::LanguageChanged);
1258    }
1259
1260    /// Assign a language registry to the buffer. This allows the buffer to retrieve
1261    /// other languages if parts of the buffer are written in different languages.
1262    pub fn set_language_registry(&self, language_registry: Arc<LanguageRegistry>) {
1263        self.syntax_map
1264            .lock()
1265            .set_language_registry(language_registry);
1266    }
1267
1268    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
1269        self.syntax_map.lock().language_registry()
1270    }
1271
1272    /// Assign the buffer a new [`Capability`].
1273    pub fn set_capability(&mut self, capability: Capability, cx: &mut Context<Self>) {
1274        self.capability = capability;
1275        cx.emit(BufferEvent::CapabilityChanged)
1276    }
1277
1278    /// This method is called to signal that the buffer has been saved.
1279    pub fn did_save(
1280        &mut self,
1281        version: clock::Global,
1282        mtime: Option<MTime>,
1283        cx: &mut Context<Self>,
1284    ) {
1285        self.saved_version = version;
1286        self.has_unsaved_edits
1287            .set((self.saved_version().clone(), false));
1288        self.has_conflict = false;
1289        self.saved_mtime = mtime;
1290        cx.emit(BufferEvent::Saved);
1291        cx.notify();
1292    }
1293
1294    /// This method is called to signal that the buffer has been discarded.
1295    pub fn discarded(&self, cx: &mut Context<Self>) {
1296        cx.emit(BufferEvent::Discarded);
1297        cx.notify();
1298    }
1299
1300    /// Reloads the contents of the buffer from disk.
1301    pub fn reload(&mut self, cx: &Context<Self>) -> oneshot::Receiver<Option<Transaction>> {
1302        let (tx, rx) = futures::channel::oneshot::channel();
1303        let prev_version = self.text.version();
1304        self.reload_task = Some(cx.spawn(|this, mut cx| async move {
1305            let Some((new_mtime, new_text)) = this.update(&mut cx, |this, cx| {
1306                let file = this.file.as_ref()?.as_local()?;
1307                Some((file.disk_state().mtime(), file.load(cx)))
1308            })?
1309            else {
1310                return Ok(());
1311            };
1312
1313            let new_text = new_text.await?;
1314            let diff = this
1315                .update(&mut cx, |this, cx| this.diff(new_text.clone(), cx))?
1316                .await;
1317            this.update(&mut cx, |this, cx| {
1318                if this.version() == diff.base_version {
1319                    this.finalize_last_transaction();
1320                    this.apply_diff(diff, cx);
1321                    tx.send(this.finalize_last_transaction().cloned()).ok();
1322                    this.has_conflict = false;
1323                    this.did_reload(this.version(), this.line_ending(), new_mtime, cx);
1324                } else {
1325                    if !diff.edits.is_empty()
1326                        || this
1327                            .edits_since::<usize>(&diff.base_version)
1328                            .next()
1329                            .is_some()
1330                    {
1331                        this.has_conflict = true;
1332                    }
1333
1334                    this.did_reload(prev_version, this.line_ending(), this.saved_mtime, cx);
1335                }
1336
1337                this.reload_task.take();
1338            })
1339        }));
1340        rx
1341    }
1342
1343    /// This method is called to signal that the buffer has been reloaded.
1344    pub fn did_reload(
1345        &mut self,
1346        version: clock::Global,
1347        line_ending: LineEnding,
1348        mtime: Option<MTime>,
1349        cx: &mut Context<Self>,
1350    ) {
1351        self.saved_version = version;
1352        self.has_unsaved_edits
1353            .set((self.saved_version.clone(), false));
1354        self.text.set_line_ending(line_ending);
1355        self.saved_mtime = mtime;
1356        cx.emit(BufferEvent::Reloaded);
1357        cx.notify();
1358    }
1359
1360    /// Updates the [`File`] backing this buffer. This should be called when
1361    /// the file has changed or has been deleted.
1362    pub fn file_updated(&mut self, new_file: Arc<dyn File>, cx: &mut Context<Self>) {
1363        let was_dirty = self.is_dirty();
1364        let mut file_changed = false;
1365
1366        if let Some(old_file) = self.file.as_ref() {
1367            if new_file.path() != old_file.path() {
1368                file_changed = true;
1369            }
1370
1371            let old_state = old_file.disk_state();
1372            let new_state = new_file.disk_state();
1373            if old_state != new_state {
1374                file_changed = true;
1375                if !was_dirty && matches!(new_state, DiskState::Present { .. }) {
1376                    cx.emit(BufferEvent::ReloadNeeded)
1377                }
1378            }
1379        } else {
1380            file_changed = true;
1381        };
1382
1383        self.file = Some(new_file);
1384        if file_changed {
1385            self.non_text_state_update_count += 1;
1386            if was_dirty != self.is_dirty() {
1387                cx.emit(BufferEvent::DirtyChanged);
1388            }
1389            cx.emit(BufferEvent::FileHandleChanged);
1390            cx.notify();
1391        }
1392    }
1393
1394    pub fn base_buffer(&self) -> Option<Entity<Self>> {
1395        Some(self.branch_state.as_ref()?.base_buffer.clone())
1396    }
1397
1398    /// Returns the primary [`Language`] assigned to this [`Buffer`].
1399    pub fn language(&self) -> Option<&Arc<Language>> {
1400        self.language.as_ref()
1401    }
1402
1403    /// Returns the [`Language`] at the given location.
1404    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
1405        let offset = position.to_offset(self);
1406        self.syntax_map
1407            .lock()
1408            .layers_for_range(offset..offset, &self.text, false)
1409            .last()
1410            .map(|info| info.language.clone())
1411            .or_else(|| self.language.clone())
1412    }
1413
1414    /// An integer version number that accounts for all updates besides
1415    /// the buffer's text itself (which is versioned via a version vector).
1416    pub fn non_text_state_update_count(&self) -> usize {
1417        self.non_text_state_update_count
1418    }
1419
1420    /// Whether the buffer is being parsed in the background.
1421    #[cfg(any(test, feature = "test-support"))]
1422    pub fn is_parsing(&self) -> bool {
1423        self.parsing_in_background
1424    }
1425
1426    /// Indicates whether the buffer contains any regions that may be
1427    /// written in a language that hasn't been loaded yet.
1428    pub fn contains_unknown_injections(&self) -> bool {
1429        self.syntax_map.lock().contains_unknown_injections()
1430    }
1431
1432    #[cfg(test)]
1433    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
1434        self.sync_parse_timeout = timeout;
1435    }
1436
1437    /// Called after an edit to synchronize the buffer's main parse tree with
1438    /// the buffer's new underlying state.
1439    ///
1440    /// Locks the syntax map and interpolates the edits since the last reparse
1441    /// into the foreground syntax tree.
1442    ///
1443    /// Then takes a stable snapshot of the syntax map before unlocking it.
1444    /// The snapshot with the interpolated edits is sent to a background thread,
1445    /// where we ask Tree-sitter to perform an incremental parse.
1446    ///
1447    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
1448    /// waiting on the parse to complete. As soon as it completes, we proceed
1449    /// synchronously, unless a 1ms timeout elapses.
1450    ///
1451    /// If we time out waiting on the parse, we spawn a second task waiting
1452    /// until the parse does complete and return with the interpolated tree still
1453    /// in the foreground. When the background parse completes, call back into
1454    /// the main thread and assign the foreground parse state.
1455    ///
1456    /// If the buffer or grammar changed since the start of the background parse,
1457    /// initiate an additional reparse recursively. To avoid concurrent parses
1458    /// for the same buffer, we only initiate a new parse if we are not already
1459    /// parsing in the background.
1460    pub fn reparse(&mut self, cx: &mut Context<Self>) {
1461        if self.parsing_in_background {
1462            return;
1463        }
1464        let language = if let Some(language) = self.language.clone() {
1465            language
1466        } else {
1467            return;
1468        };
1469
1470        let text = self.text_snapshot();
1471        let parsed_version = self.version();
1472
1473        let mut syntax_map = self.syntax_map.lock();
1474        syntax_map.interpolate(&text);
1475        let language_registry = syntax_map.language_registry();
1476        let mut syntax_snapshot = syntax_map.snapshot();
1477        drop(syntax_map);
1478
1479        let parse_task = cx.background_spawn({
1480            let language = language.clone();
1481            let language_registry = language_registry.clone();
1482            async move {
1483                syntax_snapshot.reparse(&text, language_registry, language);
1484                syntax_snapshot
1485            }
1486        });
1487
1488        self.parse_status.0.send(ParseStatus::Parsing).unwrap();
1489        match cx
1490            .background_executor()
1491            .block_with_timeout(self.sync_parse_timeout, parse_task)
1492        {
1493            Ok(new_syntax_snapshot) => {
1494                self.did_finish_parsing(new_syntax_snapshot, cx);
1495            }
1496            Err(parse_task) => {
1497                self.parsing_in_background = true;
1498                cx.spawn(move |this, mut cx| async move {
1499                    let new_syntax_map = parse_task.await;
1500                    this.update(&mut cx, move |this, cx| {
1501                        let grammar_changed =
1502                            this.language.as_ref().map_or(true, |current_language| {
1503                                !Arc::ptr_eq(&language, current_language)
1504                            });
1505                        let language_registry_changed = new_syntax_map
1506                            .contains_unknown_injections()
1507                            && language_registry.map_or(false, |registry| {
1508                                registry.version() != new_syntax_map.language_registry_version()
1509                            });
1510                        let parse_again = language_registry_changed
1511                            || grammar_changed
1512                            || this.version.changed_since(&parsed_version);
1513                        this.did_finish_parsing(new_syntax_map, cx);
1514                        this.parsing_in_background = false;
1515                        if parse_again {
1516                            this.reparse(cx);
1517                        }
1518                    })
1519                    .ok();
1520                })
1521                .detach();
1522            }
1523        }
1524    }
1525
1526    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut Context<Self>) {
1527        self.non_text_state_update_count += 1;
1528        self.syntax_map.lock().did_parse(syntax_snapshot);
1529        self.request_autoindent(cx);
1530        self.parse_status.0.send(ParseStatus::Idle).unwrap();
1531        cx.emit(BufferEvent::Reparsed);
1532        cx.notify();
1533    }
1534
1535    pub fn parse_status(&self) -> watch::Receiver<ParseStatus> {
1536        self.parse_status.1.clone()
1537    }
1538
1539    /// Assign to the buffer a set of diagnostics created by a given language server.
1540    pub fn update_diagnostics(
1541        &mut self,
1542        server_id: LanguageServerId,
1543        diagnostics: DiagnosticSet,
1544        cx: &mut Context<Self>,
1545    ) {
1546        let lamport_timestamp = self.text.lamport_clock.tick();
1547        let op = Operation::UpdateDiagnostics {
1548            server_id,
1549            diagnostics: diagnostics.iter().cloned().collect(),
1550            lamport_timestamp,
1551        };
1552        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
1553        self.send_operation(op, true, cx);
1554    }
1555
1556    fn request_autoindent(&mut self, cx: &mut Context<Self>) {
1557        if let Some(indent_sizes) = self.compute_autoindents() {
1558            let indent_sizes = cx.background_spawn(indent_sizes);
1559            match cx
1560                .background_executor()
1561                .block_with_timeout(Duration::from_micros(500), indent_sizes)
1562            {
1563                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
1564                Err(indent_sizes) => {
1565                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
1566                        let indent_sizes = indent_sizes.await;
1567                        this.update(&mut cx, |this, cx| {
1568                            this.apply_autoindents(indent_sizes, cx);
1569                        })
1570                        .ok();
1571                    }));
1572                }
1573            }
1574        } else {
1575            self.autoindent_requests.clear();
1576        }
1577    }
1578
1579    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
1580        let max_rows_between_yields = 100;
1581        let snapshot = self.snapshot();
1582        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
1583            return None;
1584        }
1585
1586        let autoindent_requests = self.autoindent_requests.clone();
1587        Some(async move {
1588            let mut indent_sizes = BTreeMap::<u32, (IndentSize, bool)>::new();
1589            for request in autoindent_requests {
1590                // Resolve each edited range to its row in the current buffer and in the
1591                // buffer before this batch of edits.
1592                let mut row_ranges = Vec::new();
1593                let mut old_to_new_rows = BTreeMap::new();
1594                let mut language_indent_sizes_by_new_row = Vec::new();
1595                for entry in &request.entries {
1596                    let position = entry.range.start;
1597                    let new_row = position.to_point(&snapshot).row;
1598                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
1599                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
1600
1601                    if !entry.first_line_is_new {
1602                        let old_row = position.to_point(&request.before_edit).row;
1603                        old_to_new_rows.insert(old_row, new_row);
1604                    }
1605                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
1606                }
1607
1608                // Build a map containing the suggested indentation for each of the edited lines
1609                // with respect to the state of the buffer before these edits. This map is keyed
1610                // by the rows for these lines in the current state of the buffer.
1611                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
1612                let old_edited_ranges =
1613                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
1614                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1615                let mut language_indent_size = IndentSize::default();
1616                for old_edited_range in old_edited_ranges {
1617                    let suggestions = request
1618                        .before_edit
1619                        .suggest_autoindents(old_edited_range.clone())
1620                        .into_iter()
1621                        .flatten();
1622                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1623                        if let Some(suggestion) = suggestion {
1624                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
1625
1626                            // Find the indent size based on the language for this row.
1627                            while let Some((row, size)) = language_indent_sizes.peek() {
1628                                if *row > new_row {
1629                                    break;
1630                                }
1631                                language_indent_size = *size;
1632                                language_indent_sizes.next();
1633                            }
1634
1635                            let suggested_indent = old_to_new_rows
1636                                .get(&suggestion.basis_row)
1637                                .and_then(|from_row| {
1638                                    Some(old_suggestions.get(from_row).copied()?.0)
1639                                })
1640                                .unwrap_or_else(|| {
1641                                    request
1642                                        .before_edit
1643                                        .indent_size_for_line(suggestion.basis_row)
1644                                })
1645                                .with_delta(suggestion.delta, language_indent_size);
1646                            old_suggestions
1647                                .insert(new_row, (suggested_indent, suggestion.within_error));
1648                        }
1649                    }
1650                    yield_now().await;
1651                }
1652
1653                // Compute new suggestions for each line, but only include them in the result
1654                // if they differ from the old suggestion for that line.
1655                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1656                let mut language_indent_size = IndentSize::default();
1657                for (row_range, original_indent_column) in row_ranges {
1658                    let new_edited_row_range = if request.is_block_mode {
1659                        row_range.start..row_range.start + 1
1660                    } else {
1661                        row_range.clone()
1662                    };
1663
1664                    let suggestions = snapshot
1665                        .suggest_autoindents(new_edited_row_range.clone())
1666                        .into_iter()
1667                        .flatten();
1668                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1669                        if let Some(suggestion) = suggestion {
1670                            // Find the indent size based on the language for this row.
1671                            while let Some((row, size)) = language_indent_sizes.peek() {
1672                                if *row > new_row {
1673                                    break;
1674                                }
1675                                language_indent_size = *size;
1676                                language_indent_sizes.next();
1677                            }
1678
1679                            let suggested_indent = indent_sizes
1680                                .get(&suggestion.basis_row)
1681                                .copied()
1682                                .map(|e| e.0)
1683                                .unwrap_or_else(|| {
1684                                    snapshot.indent_size_for_line(suggestion.basis_row)
1685                                })
1686                                .with_delta(suggestion.delta, language_indent_size);
1687
1688                            if old_suggestions.get(&new_row).map_or(
1689                                true,
1690                                |(old_indentation, was_within_error)| {
1691                                    suggested_indent != *old_indentation
1692                                        && (!suggestion.within_error || *was_within_error)
1693                                },
1694                            ) {
1695                                indent_sizes.insert(
1696                                    new_row,
1697                                    (suggested_indent, request.ignore_empty_lines),
1698                                );
1699                            }
1700                        }
1701                    }
1702
1703                    if let (true, Some(original_indent_column)) =
1704                        (request.is_block_mode, original_indent_column)
1705                    {
1706                        let new_indent =
1707                            if let Some((indent, _)) = indent_sizes.get(&row_range.start) {
1708                                *indent
1709                            } else {
1710                                snapshot.indent_size_for_line(row_range.start)
1711                            };
1712                        let delta = new_indent.len as i64 - original_indent_column as i64;
1713                        if delta != 0 {
1714                            for row in row_range.skip(1) {
1715                                indent_sizes.entry(row).or_insert_with(|| {
1716                                    let mut size = snapshot.indent_size_for_line(row);
1717                                    if size.kind == new_indent.kind {
1718                                        match delta.cmp(&0) {
1719                                            Ordering::Greater => size.len += delta as u32,
1720                                            Ordering::Less => {
1721                                                size.len = size.len.saturating_sub(-delta as u32)
1722                                            }
1723                                            Ordering::Equal => {}
1724                                        }
1725                                    }
1726                                    (size, request.ignore_empty_lines)
1727                                });
1728                            }
1729                        }
1730                    }
1731
1732                    yield_now().await;
1733                }
1734            }
1735
1736            indent_sizes
1737                .into_iter()
1738                .filter_map(|(row, (indent, ignore_empty_lines))| {
1739                    if ignore_empty_lines && snapshot.line_len(row) == 0 {
1740                        None
1741                    } else {
1742                        Some((row, indent))
1743                    }
1744                })
1745                .collect()
1746        })
1747    }
1748
1749    fn apply_autoindents(
1750        &mut self,
1751        indent_sizes: BTreeMap<u32, IndentSize>,
1752        cx: &mut Context<Self>,
1753    ) {
1754        self.autoindent_requests.clear();
1755
1756        let edits: Vec<_> = indent_sizes
1757            .into_iter()
1758            .filter_map(|(row, indent_size)| {
1759                let current_size = indent_size_for_line(self, row);
1760                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1761            })
1762            .collect();
1763
1764        let preserve_preview = self.preserve_preview();
1765        self.edit(edits, None, cx);
1766        if preserve_preview {
1767            self.refresh_preview();
1768        }
1769    }
1770
1771    /// Create a minimal edit that will cause the given row to be indented
1772    /// with the given size. After applying this edit, the length of the line
1773    /// will always be at least `new_size.len`.
1774    pub fn edit_for_indent_size_adjustment(
1775        row: u32,
1776        current_size: IndentSize,
1777        new_size: IndentSize,
1778    ) -> Option<(Range<Point>, String)> {
1779        if new_size.kind == current_size.kind {
1780            match new_size.len.cmp(&current_size.len) {
1781                Ordering::Greater => {
1782                    let point = Point::new(row, 0);
1783                    Some((
1784                        point..point,
1785                        iter::repeat(new_size.char())
1786                            .take((new_size.len - current_size.len) as usize)
1787                            .collect::<String>(),
1788                    ))
1789                }
1790
1791                Ordering::Less => Some((
1792                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1793                    String::new(),
1794                )),
1795
1796                Ordering::Equal => None,
1797            }
1798        } else {
1799            Some((
1800                Point::new(row, 0)..Point::new(row, current_size.len),
1801                iter::repeat(new_size.char())
1802                    .take(new_size.len as usize)
1803                    .collect::<String>(),
1804            ))
1805        }
1806    }
1807
1808    /// Spawns a background task that asynchronously computes a `Diff` between the buffer's text
1809    /// and the given new text.
1810    pub fn diff(&self, mut new_text: String, cx: &App) -> Task<Diff> {
1811        let old_text = self.as_rope().clone();
1812        let base_version = self.version();
1813        cx.background_executor()
1814            .spawn_labeled(*BUFFER_DIFF_TASK, async move {
1815                let old_text = old_text.to_string();
1816                let line_ending = LineEnding::detect(&new_text);
1817                LineEnding::normalize(&mut new_text);
1818                let edits = text_diff(&old_text, &new_text);
1819                Diff {
1820                    base_version,
1821                    line_ending,
1822                    edits,
1823                }
1824            })
1825    }
1826
1827    /// Spawns a background task that searches the buffer for any whitespace
1828    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1829    pub fn remove_trailing_whitespace(&self, cx: &App) -> Task<Diff> {
1830        let old_text = self.as_rope().clone();
1831        let line_ending = self.line_ending();
1832        let base_version = self.version();
1833        cx.background_spawn(async move {
1834            let ranges = trailing_whitespace_ranges(&old_text);
1835            let empty = Arc::<str>::from("");
1836            Diff {
1837                base_version,
1838                line_ending,
1839                edits: ranges
1840                    .into_iter()
1841                    .map(|range| (range, empty.clone()))
1842                    .collect(),
1843            }
1844        })
1845    }
1846
1847    /// Ensures that the buffer ends with a single newline character, and
1848    /// no other whitespace.
1849    pub fn ensure_final_newline(&mut self, cx: &mut Context<Self>) {
1850        let len = self.len();
1851        let mut offset = len;
1852        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1853            let non_whitespace_len = chunk
1854                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1855                .len();
1856            offset -= chunk.len();
1857            offset += non_whitespace_len;
1858            if non_whitespace_len != 0 {
1859                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1860                    return;
1861                }
1862                break;
1863            }
1864        }
1865        self.edit([(offset..len, "\n")], None, cx);
1866    }
1867
1868    /// Applies a diff to the buffer. If the buffer has changed since the given diff was
1869    /// calculated, then adjust the diff to account for those changes, and discard any
1870    /// parts of the diff that conflict with those changes.
1871    pub fn apply_diff(&mut self, diff: Diff, cx: &mut Context<Self>) -> Option<TransactionId> {
1872        // Check for any edits to the buffer that have occurred since this diff
1873        // was computed.
1874        let snapshot = self.snapshot();
1875        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1876        let mut delta = 0;
1877        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1878            while let Some(edit_since) = edits_since.peek() {
1879                // If the edit occurs after a diff hunk, then it does not
1880                // affect that hunk.
1881                if edit_since.old.start > range.end {
1882                    break;
1883                }
1884                // If the edit precedes the diff hunk, then adjust the hunk
1885                // to reflect the edit.
1886                else if edit_since.old.end < range.start {
1887                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1888                    edits_since.next();
1889                }
1890                // If the edit intersects a diff hunk, then discard that hunk.
1891                else {
1892                    return None;
1893                }
1894            }
1895
1896            let start = (range.start as i64 + delta) as usize;
1897            let end = (range.end as i64 + delta) as usize;
1898            Some((start..end, new_text))
1899        });
1900
1901        self.start_transaction();
1902        self.text.set_line_ending(diff.line_ending);
1903        self.edit(adjusted_edits, None, cx);
1904        self.end_transaction(cx)
1905    }
1906
1907    fn has_unsaved_edits(&self) -> bool {
1908        let (last_version, has_unsaved_edits) = self.has_unsaved_edits.take();
1909
1910        if last_version == self.version {
1911            self.has_unsaved_edits
1912                .set((last_version, has_unsaved_edits));
1913            return has_unsaved_edits;
1914        }
1915
1916        let has_edits = self.has_edits_since(&self.saved_version);
1917        self.has_unsaved_edits
1918            .set((self.version.clone(), has_edits));
1919        has_edits
1920    }
1921
1922    /// Checks if the buffer has unsaved changes.
1923    pub fn is_dirty(&self) -> bool {
1924        if self.capability == Capability::ReadOnly {
1925            return false;
1926        }
1927        if self.has_conflict || self.has_unsaved_edits() {
1928            return true;
1929        }
1930        match self.file.as_ref().map(|f| f.disk_state()) {
1931            Some(DiskState::New) => !self.is_empty(),
1932            Some(DiskState::Deleted) => true,
1933            _ => false,
1934        }
1935    }
1936
1937    /// Checks if the buffer and its file have both changed since the buffer
1938    /// was last saved or reloaded.
1939    pub fn has_conflict(&self) -> bool {
1940        if self.has_conflict {
1941            return true;
1942        }
1943        let Some(file) = self.file.as_ref() else {
1944            return false;
1945        };
1946        match file.disk_state() {
1947            DiskState::New => false,
1948            DiskState::Present { mtime } => match self.saved_mtime {
1949                Some(saved_mtime) => {
1950                    mtime.bad_is_greater_than(saved_mtime) && self.has_unsaved_edits()
1951                }
1952                None => true,
1953            },
1954            DiskState::Deleted => true,
1955        }
1956    }
1957
1958    /// Gets a [`Subscription`] that tracks all of the changes to the buffer's text.
1959    pub fn subscribe(&mut self) -> Subscription {
1960        self.text.subscribe()
1961    }
1962
1963    /// Starts a transaction, if one is not already in-progress. When undoing or
1964    /// redoing edits, all of the edits performed within a transaction are undone
1965    /// or redone together.
1966    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1967        self.start_transaction_at(Instant::now())
1968    }
1969
1970    /// Starts a transaction, providing the current time. Subsequent transactions
1971    /// that occur within a short period of time will be grouped together. This
1972    /// is controlled by the buffer's undo grouping duration.
1973    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1974        self.transaction_depth += 1;
1975        if self.was_dirty_before_starting_transaction.is_none() {
1976            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1977        }
1978        self.text.start_transaction_at(now)
1979    }
1980
1981    /// Terminates the current transaction, if this is the outermost transaction.
1982    pub fn end_transaction(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
1983        self.end_transaction_at(Instant::now(), cx)
1984    }
1985
1986    /// Terminates the current transaction, providing the current time. Subsequent transactions
1987    /// that occur within a short period of time will be grouped together. This
1988    /// is controlled by the buffer's undo grouping duration.
1989    pub fn end_transaction_at(
1990        &mut self,
1991        now: Instant,
1992        cx: &mut Context<Self>,
1993    ) -> Option<TransactionId> {
1994        assert!(self.transaction_depth > 0);
1995        self.transaction_depth -= 1;
1996        let was_dirty = if self.transaction_depth == 0 {
1997            self.was_dirty_before_starting_transaction.take().unwrap()
1998        } else {
1999            false
2000        };
2001        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
2002            self.did_edit(&start_version, was_dirty, cx);
2003            Some(transaction_id)
2004        } else {
2005            None
2006        }
2007    }
2008
2009    /// Manually add a transaction to the buffer's undo history.
2010    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
2011        self.text.push_transaction(transaction, now);
2012    }
2013
2014    /// Prevent the last transaction from being grouped with any subsequent transactions,
2015    /// even if they occur with the buffer's undo grouping duration.
2016    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
2017        self.text.finalize_last_transaction()
2018    }
2019
2020    /// Manually group all changes since a given transaction.
2021    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
2022        self.text.group_until_transaction(transaction_id);
2023    }
2024
2025    /// Manually remove a transaction from the buffer's undo history
2026    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
2027        self.text.forget_transaction(transaction_id);
2028    }
2029
2030    /// Manually merge two adjacent transactions in the buffer's undo history.
2031    pub fn merge_transactions(&mut self, transaction: TransactionId, destination: TransactionId) {
2032        self.text.merge_transactions(transaction, destination);
2033    }
2034
2035    /// Waits for the buffer to receive operations with the given timestamps.
2036    pub fn wait_for_edits(
2037        &mut self,
2038        edit_ids: impl IntoIterator<Item = clock::Lamport>,
2039    ) -> impl Future<Output = Result<()>> {
2040        self.text.wait_for_edits(edit_ids)
2041    }
2042
2043    /// Waits for the buffer to receive the operations necessary for resolving the given anchors.
2044    pub fn wait_for_anchors(
2045        &mut self,
2046        anchors: impl IntoIterator<Item = Anchor>,
2047    ) -> impl 'static + Future<Output = Result<()>> {
2048        self.text.wait_for_anchors(anchors)
2049    }
2050
2051    /// Waits for the buffer to receive operations up to the given version.
2052    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = Result<()>> {
2053        self.text.wait_for_version(version)
2054    }
2055
2056    /// Forces all futures returned by [`Buffer::wait_for_version`], [`Buffer::wait_for_edits`], or
2057    /// [`Buffer::wait_for_version`] to resolve with an error.
2058    pub fn give_up_waiting(&mut self) {
2059        self.text.give_up_waiting();
2060    }
2061
2062    /// Stores a set of selections that should be broadcasted to all of the buffer's replicas.
2063    pub fn set_active_selections(
2064        &mut self,
2065        selections: Arc<[Selection<Anchor>]>,
2066        line_mode: bool,
2067        cursor_shape: CursorShape,
2068        cx: &mut Context<Self>,
2069    ) {
2070        let lamport_timestamp = self.text.lamport_clock.tick();
2071        self.remote_selections.insert(
2072            self.text.replica_id(),
2073            SelectionSet {
2074                selections: selections.clone(),
2075                lamport_timestamp,
2076                line_mode,
2077                cursor_shape,
2078            },
2079        );
2080        self.send_operation(
2081            Operation::UpdateSelections {
2082                selections,
2083                line_mode,
2084                lamport_timestamp,
2085                cursor_shape,
2086            },
2087            true,
2088            cx,
2089        );
2090        self.non_text_state_update_count += 1;
2091        cx.notify();
2092    }
2093
2094    /// Clears the selections, so that other replicas of the buffer do not see any selections for
2095    /// this replica.
2096    pub fn remove_active_selections(&mut self, cx: &mut Context<Self>) {
2097        if self
2098            .remote_selections
2099            .get(&self.text.replica_id())
2100            .map_or(true, |set| !set.selections.is_empty())
2101        {
2102            self.set_active_selections(Arc::default(), false, Default::default(), cx);
2103        }
2104    }
2105
2106    /// Replaces the buffer's entire text.
2107    pub fn set_text<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2108    where
2109        T: Into<Arc<str>>,
2110    {
2111        self.autoindent_requests.clear();
2112        self.edit([(0..self.len(), text)], None, cx)
2113    }
2114
2115    /// Applies the given edits to the buffer. Each edit is specified as a range of text to
2116    /// delete, and a string of text to insert at that location.
2117    ///
2118    /// If an [`AutoindentMode`] is provided, then the buffer will enqueue an auto-indent
2119    /// request for the edited ranges, which will be processed when the buffer finishes
2120    /// parsing.
2121    ///
2122    /// Parsing takes place at the end of a transaction, and may compute synchronously
2123    /// or asynchronously, depending on the changes.
2124    pub fn edit<I, S, T>(
2125        &mut self,
2126        edits_iter: I,
2127        autoindent_mode: Option<AutoindentMode>,
2128        cx: &mut Context<Self>,
2129    ) -> Option<clock::Lamport>
2130    where
2131        I: IntoIterator<Item = (Range<S>, T)>,
2132        S: ToOffset,
2133        T: Into<Arc<str>>,
2134    {
2135        // Skip invalid edits and coalesce contiguous ones.
2136        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
2137        for (range, new_text) in edits_iter {
2138            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
2139            if range.start > range.end {
2140                mem::swap(&mut range.start, &mut range.end);
2141            }
2142            let new_text = new_text.into();
2143            if !new_text.is_empty() || !range.is_empty() {
2144                if let Some((prev_range, prev_text)) = edits.last_mut() {
2145                    if prev_range.end >= range.start {
2146                        prev_range.end = cmp::max(prev_range.end, range.end);
2147                        *prev_text = format!("{prev_text}{new_text}").into();
2148                    } else {
2149                        edits.push((range, new_text));
2150                    }
2151                } else {
2152                    edits.push((range, new_text));
2153                }
2154            }
2155        }
2156        if edits.is_empty() {
2157            return None;
2158        }
2159
2160        self.start_transaction();
2161        self.pending_autoindent.take();
2162        let autoindent_request = autoindent_mode
2163            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
2164
2165        let edit_operation = self.text.edit(edits.iter().cloned());
2166        let edit_id = edit_operation.timestamp();
2167
2168        if let Some((before_edit, mode)) = autoindent_request {
2169            let mut delta = 0isize;
2170            let entries = edits
2171                .into_iter()
2172                .enumerate()
2173                .zip(&edit_operation.as_edit().unwrap().new_text)
2174                .map(|((ix, (range, _)), new_text)| {
2175                    let new_text_length = new_text.len();
2176                    let old_start = range.start.to_point(&before_edit);
2177                    let new_start = (delta + range.start as isize) as usize;
2178                    let range_len = range.end - range.start;
2179                    delta += new_text_length as isize - range_len as isize;
2180
2181                    // Decide what range of the insertion to auto-indent, and whether
2182                    // the first line of the insertion should be considered a newly-inserted line
2183                    // or an edit to an existing line.
2184                    let mut range_of_insertion_to_indent = 0..new_text_length;
2185                    let mut first_line_is_new = true;
2186
2187                    let old_line_start = before_edit.indent_size_for_line(old_start.row).len;
2188                    let old_line_end = before_edit.line_len(old_start.row);
2189
2190                    if old_start.column > old_line_start {
2191                        first_line_is_new = false;
2192                    }
2193
2194                    if !new_text.contains('\n')
2195                        && (old_start.column + (range_len as u32) < old_line_end
2196                            || old_line_end == old_line_start)
2197                    {
2198                        first_line_is_new = false;
2199                    }
2200
2201                    // When inserting text starting with a newline, avoid auto-indenting the
2202                    // previous line.
2203                    if new_text.starts_with('\n') {
2204                        range_of_insertion_to_indent.start += 1;
2205                        first_line_is_new = true;
2206                    }
2207
2208                    let mut original_indent_column = None;
2209                    if let AutoindentMode::Block {
2210                        original_start_columns,
2211                    } = &mode
2212                    {
2213                        original_indent_column = Some(
2214                            original_start_columns.get(ix).copied().unwrap_or(0)
2215                                + indent_size_for_text(
2216                                    new_text[range_of_insertion_to_indent.clone()].chars(),
2217                                )
2218                                .len,
2219                        );
2220
2221                        // Avoid auto-indenting the line after the edit.
2222                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
2223                            range_of_insertion_to_indent.end -= 1;
2224                        }
2225                    }
2226
2227                    AutoindentRequestEntry {
2228                        first_line_is_new,
2229                        original_indent_column,
2230                        indent_size: before_edit.language_indent_size_at(range.start, cx),
2231                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
2232                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
2233                    }
2234                })
2235                .collect();
2236
2237            self.autoindent_requests.push(Arc::new(AutoindentRequest {
2238                before_edit,
2239                entries,
2240                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
2241                ignore_empty_lines: false,
2242            }));
2243        }
2244
2245        self.end_transaction(cx);
2246        self.send_operation(Operation::Buffer(edit_operation), true, cx);
2247        Some(edit_id)
2248    }
2249
2250    fn did_edit(&mut self, old_version: &clock::Global, was_dirty: bool, cx: &mut Context<Self>) {
2251        if self.edits_since::<usize>(old_version).next().is_none() {
2252            return;
2253        }
2254
2255        self.reparse(cx);
2256
2257        cx.emit(BufferEvent::Edited);
2258        if was_dirty != self.is_dirty() {
2259            cx.emit(BufferEvent::DirtyChanged);
2260        }
2261        cx.notify();
2262    }
2263
2264    pub fn autoindent_ranges<I, T>(&mut self, ranges: I, cx: &mut Context<Self>)
2265    where
2266        I: IntoIterator<Item = Range<T>>,
2267        T: ToOffset + Copy,
2268    {
2269        let before_edit = self.snapshot();
2270        let entries = ranges
2271            .into_iter()
2272            .map(|range| AutoindentRequestEntry {
2273                range: before_edit.anchor_before(range.start)..before_edit.anchor_after(range.end),
2274                first_line_is_new: true,
2275                indent_size: before_edit.language_indent_size_at(range.start, cx),
2276                original_indent_column: None,
2277            })
2278            .collect();
2279        self.autoindent_requests.push(Arc::new(AutoindentRequest {
2280            before_edit,
2281            entries,
2282            is_block_mode: false,
2283            ignore_empty_lines: true,
2284        }));
2285        self.request_autoindent(cx);
2286    }
2287
2288    // Inserts newlines at the given position to create an empty line, returning the start of the new line.
2289    // You can also request the insertion of empty lines above and below the line starting at the returned point.
2290    pub fn insert_empty_line(
2291        &mut self,
2292        position: impl ToPoint,
2293        space_above: bool,
2294        space_below: bool,
2295        cx: &mut Context<Self>,
2296    ) -> Point {
2297        let mut position = position.to_point(self);
2298
2299        self.start_transaction();
2300
2301        self.edit(
2302            [(position..position, "\n")],
2303            Some(AutoindentMode::EachLine),
2304            cx,
2305        );
2306
2307        if position.column > 0 {
2308            position += Point::new(1, 0);
2309        }
2310
2311        if !self.is_line_blank(position.row) {
2312            self.edit(
2313                [(position..position, "\n")],
2314                Some(AutoindentMode::EachLine),
2315                cx,
2316            );
2317        }
2318
2319        if space_above && position.row > 0 && !self.is_line_blank(position.row - 1) {
2320            self.edit(
2321                [(position..position, "\n")],
2322                Some(AutoindentMode::EachLine),
2323                cx,
2324            );
2325            position.row += 1;
2326        }
2327
2328        if space_below
2329            && (position.row == self.max_point().row || !self.is_line_blank(position.row + 1))
2330        {
2331            self.edit(
2332                [(position..position, "\n")],
2333                Some(AutoindentMode::EachLine),
2334                cx,
2335            );
2336        }
2337
2338        self.end_transaction(cx);
2339
2340        position
2341    }
2342
2343    /// Applies the given remote operations to the buffer.
2344    pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I, cx: &mut Context<Self>) {
2345        self.pending_autoindent.take();
2346        let was_dirty = self.is_dirty();
2347        let old_version = self.version.clone();
2348        let mut deferred_ops = Vec::new();
2349        let buffer_ops = ops
2350            .into_iter()
2351            .filter_map(|op| match op {
2352                Operation::Buffer(op) => Some(op),
2353                _ => {
2354                    if self.can_apply_op(&op) {
2355                        self.apply_op(op, cx);
2356                    } else {
2357                        deferred_ops.push(op);
2358                    }
2359                    None
2360                }
2361            })
2362            .collect::<Vec<_>>();
2363        for operation in buffer_ops.iter() {
2364            self.send_operation(Operation::Buffer(operation.clone()), false, cx);
2365        }
2366        self.text.apply_ops(buffer_ops);
2367        self.deferred_ops.insert(deferred_ops);
2368        self.flush_deferred_ops(cx);
2369        self.did_edit(&old_version, was_dirty, cx);
2370        // Notify independently of whether the buffer was edited as the operations could include a
2371        // selection update.
2372        cx.notify();
2373    }
2374
2375    fn flush_deferred_ops(&mut self, cx: &mut Context<Self>) {
2376        let mut deferred_ops = Vec::new();
2377        for op in self.deferred_ops.drain().iter().cloned() {
2378            if self.can_apply_op(&op) {
2379                self.apply_op(op, cx);
2380            } else {
2381                deferred_ops.push(op);
2382            }
2383        }
2384        self.deferred_ops.insert(deferred_ops);
2385    }
2386
2387    pub fn has_deferred_ops(&self) -> bool {
2388        !self.deferred_ops.is_empty() || self.text.has_deferred_ops()
2389    }
2390
2391    fn can_apply_op(&self, operation: &Operation) -> bool {
2392        match operation {
2393            Operation::Buffer(_) => {
2394                unreachable!("buffer operations should never be applied at this layer")
2395            }
2396            Operation::UpdateDiagnostics {
2397                diagnostics: diagnostic_set,
2398                ..
2399            } => diagnostic_set.iter().all(|diagnostic| {
2400                self.text.can_resolve(&diagnostic.range.start)
2401                    && self.text.can_resolve(&diagnostic.range.end)
2402            }),
2403            Operation::UpdateSelections { selections, .. } => selections
2404                .iter()
2405                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
2406            Operation::UpdateCompletionTriggers { .. } => true,
2407        }
2408    }
2409
2410    fn apply_op(&mut self, operation: Operation, cx: &mut Context<Self>) {
2411        match operation {
2412            Operation::Buffer(_) => {
2413                unreachable!("buffer operations should never be applied at this layer")
2414            }
2415            Operation::UpdateDiagnostics {
2416                server_id,
2417                diagnostics: diagnostic_set,
2418                lamport_timestamp,
2419            } => {
2420                let snapshot = self.snapshot();
2421                self.apply_diagnostic_update(
2422                    server_id,
2423                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
2424                    lamport_timestamp,
2425                    cx,
2426                );
2427            }
2428            Operation::UpdateSelections {
2429                selections,
2430                lamport_timestamp,
2431                line_mode,
2432                cursor_shape,
2433            } => {
2434                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
2435                    if set.lamport_timestamp > lamport_timestamp {
2436                        return;
2437                    }
2438                }
2439
2440                self.remote_selections.insert(
2441                    lamport_timestamp.replica_id,
2442                    SelectionSet {
2443                        selections,
2444                        lamport_timestamp,
2445                        line_mode,
2446                        cursor_shape,
2447                    },
2448                );
2449                self.text.lamport_clock.observe(lamport_timestamp);
2450                self.non_text_state_update_count += 1;
2451            }
2452            Operation::UpdateCompletionTriggers {
2453                triggers,
2454                lamport_timestamp,
2455                server_id,
2456            } => {
2457                if triggers.is_empty() {
2458                    self.completion_triggers_per_language_server
2459                        .remove(&server_id);
2460                    self.completion_triggers = self
2461                        .completion_triggers_per_language_server
2462                        .values()
2463                        .flat_map(|triggers| triggers.into_iter().cloned())
2464                        .collect();
2465                } else {
2466                    self.completion_triggers_per_language_server
2467                        .insert(server_id, triggers.iter().cloned().collect());
2468                    self.completion_triggers.extend(triggers);
2469                }
2470                self.text.lamport_clock.observe(lamport_timestamp);
2471            }
2472        }
2473    }
2474
2475    fn apply_diagnostic_update(
2476        &mut self,
2477        server_id: LanguageServerId,
2478        diagnostics: DiagnosticSet,
2479        lamport_timestamp: clock::Lamport,
2480        cx: &mut Context<Self>,
2481    ) {
2482        if lamport_timestamp > self.diagnostics_timestamp {
2483            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
2484            if diagnostics.is_empty() {
2485                if let Ok(ix) = ix {
2486                    self.diagnostics.remove(ix);
2487                }
2488            } else {
2489                match ix {
2490                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
2491                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
2492                };
2493            }
2494            self.diagnostics_timestamp = lamport_timestamp;
2495            self.non_text_state_update_count += 1;
2496            self.text.lamport_clock.observe(lamport_timestamp);
2497            cx.notify();
2498            cx.emit(BufferEvent::DiagnosticsUpdated);
2499        }
2500    }
2501
2502    fn send_operation(&self, operation: Operation, is_local: bool, cx: &mut Context<Self>) {
2503        cx.emit(BufferEvent::Operation {
2504            operation,
2505            is_local,
2506        });
2507    }
2508
2509    /// Removes the selections for a given peer.
2510    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut Context<Self>) {
2511        self.remote_selections.remove(&replica_id);
2512        cx.notify();
2513    }
2514
2515    /// Undoes the most recent transaction.
2516    pub fn undo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2517        let was_dirty = self.is_dirty();
2518        let old_version = self.version.clone();
2519
2520        if let Some((transaction_id, operation)) = self.text.undo() {
2521            self.send_operation(Operation::Buffer(operation), true, cx);
2522            self.did_edit(&old_version, was_dirty, cx);
2523            Some(transaction_id)
2524        } else {
2525            None
2526        }
2527    }
2528
2529    /// Manually undoes a specific transaction in the buffer's undo history.
2530    pub fn undo_transaction(
2531        &mut self,
2532        transaction_id: TransactionId,
2533        cx: &mut Context<Self>,
2534    ) -> bool {
2535        let was_dirty = self.is_dirty();
2536        let old_version = self.version.clone();
2537        if let Some(operation) = self.text.undo_transaction(transaction_id) {
2538            self.send_operation(Operation::Buffer(operation), true, cx);
2539            self.did_edit(&old_version, was_dirty, cx);
2540            true
2541        } else {
2542            false
2543        }
2544    }
2545
2546    /// Manually undoes all changes after a given transaction in the buffer's undo history.
2547    pub fn undo_to_transaction(
2548        &mut self,
2549        transaction_id: TransactionId,
2550        cx: &mut Context<Self>,
2551    ) -> bool {
2552        let was_dirty = self.is_dirty();
2553        let old_version = self.version.clone();
2554
2555        let operations = self.text.undo_to_transaction(transaction_id);
2556        let undone = !operations.is_empty();
2557        for operation in operations {
2558            self.send_operation(Operation::Buffer(operation), true, cx);
2559        }
2560        if undone {
2561            self.did_edit(&old_version, was_dirty, cx)
2562        }
2563        undone
2564    }
2565
2566    pub fn undo_operations(&mut self, counts: HashMap<Lamport, u32>, cx: &mut Context<Buffer>) {
2567        let was_dirty = self.is_dirty();
2568        let operation = self.text.undo_operations(counts);
2569        let old_version = self.version.clone();
2570        self.send_operation(Operation::Buffer(operation), true, cx);
2571        self.did_edit(&old_version, was_dirty, cx);
2572    }
2573
2574    /// Manually redoes a specific transaction in the buffer's redo history.
2575    pub fn redo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2576        let was_dirty = self.is_dirty();
2577        let old_version = self.version.clone();
2578
2579        if let Some((transaction_id, operation)) = self.text.redo() {
2580            self.send_operation(Operation::Buffer(operation), true, cx);
2581            self.did_edit(&old_version, was_dirty, cx);
2582            Some(transaction_id)
2583        } else {
2584            None
2585        }
2586    }
2587
2588    /// Manually undoes all changes until a given transaction in the buffer's redo history.
2589    pub fn redo_to_transaction(
2590        &mut self,
2591        transaction_id: TransactionId,
2592        cx: &mut Context<Self>,
2593    ) -> bool {
2594        let was_dirty = self.is_dirty();
2595        let old_version = self.version.clone();
2596
2597        let operations = self.text.redo_to_transaction(transaction_id);
2598        let redone = !operations.is_empty();
2599        for operation in operations {
2600            self.send_operation(Operation::Buffer(operation), true, cx);
2601        }
2602        if redone {
2603            self.did_edit(&old_version, was_dirty, cx)
2604        }
2605        redone
2606    }
2607
2608    /// Override current completion triggers with the user-provided completion triggers.
2609    pub fn set_completion_triggers(
2610        &mut self,
2611        server_id: LanguageServerId,
2612        triggers: BTreeSet<String>,
2613        cx: &mut Context<Self>,
2614    ) {
2615        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
2616        if triggers.is_empty() {
2617            self.completion_triggers_per_language_server
2618                .remove(&server_id);
2619            self.completion_triggers = self
2620                .completion_triggers_per_language_server
2621                .values()
2622                .flat_map(|triggers| triggers.into_iter().cloned())
2623                .collect();
2624        } else {
2625            self.completion_triggers_per_language_server
2626                .insert(server_id, triggers.clone());
2627            self.completion_triggers.extend(triggers.iter().cloned());
2628        }
2629        self.send_operation(
2630            Operation::UpdateCompletionTriggers {
2631                triggers: triggers.iter().cloned().collect(),
2632                lamport_timestamp: self.completion_triggers_timestamp,
2633                server_id,
2634            },
2635            true,
2636            cx,
2637        );
2638        cx.notify();
2639    }
2640
2641    /// Returns a list of strings which trigger a completion menu for this language.
2642    /// Usually this is driven by LSP server which returns a list of trigger characters for completions.
2643    pub fn completion_triggers(&self) -> &BTreeSet<String> {
2644        &self.completion_triggers
2645    }
2646
2647    /// Call this directly after performing edits to prevent the preview tab
2648    /// from being dismissed by those edits. It causes `should_dismiss_preview`
2649    /// to return false until there are additional edits.
2650    pub fn refresh_preview(&mut self) {
2651        self.preview_version = self.version.clone();
2652    }
2653
2654    /// Whether we should preserve the preview status of a tab containing this buffer.
2655    pub fn preserve_preview(&self) -> bool {
2656        !self.has_edits_since(&self.preview_version)
2657    }
2658}
2659
2660#[doc(hidden)]
2661#[cfg(any(test, feature = "test-support"))]
2662impl Buffer {
2663    pub fn edit_via_marked_text(
2664        &mut self,
2665        marked_string: &str,
2666        autoindent_mode: Option<AutoindentMode>,
2667        cx: &mut Context<Self>,
2668    ) {
2669        let edits = self.edits_for_marked_text(marked_string);
2670        self.edit(edits, autoindent_mode, cx);
2671    }
2672
2673    pub fn set_group_interval(&mut self, group_interval: Duration) {
2674        self.text.set_group_interval(group_interval);
2675    }
2676
2677    pub fn randomly_edit<T>(&mut self, rng: &mut T, old_range_count: usize, cx: &mut Context<Self>)
2678    where
2679        T: rand::Rng,
2680    {
2681        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
2682        let mut last_end = None;
2683        for _ in 0..old_range_count {
2684            if last_end.map_or(false, |last_end| last_end >= self.len()) {
2685                break;
2686            }
2687
2688            let new_start = last_end.map_or(0, |last_end| last_end + 1);
2689            let mut range = self.random_byte_range(new_start, rng);
2690            if rng.gen_bool(0.2) {
2691                mem::swap(&mut range.start, &mut range.end);
2692            }
2693            last_end = Some(range.end);
2694
2695            let new_text_len = rng.gen_range(0..10);
2696            let mut new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
2697            new_text = new_text.to_uppercase();
2698
2699            edits.push((range, new_text));
2700        }
2701        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
2702        self.edit(edits, None, cx);
2703    }
2704
2705    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut Context<Self>) {
2706        let was_dirty = self.is_dirty();
2707        let old_version = self.version.clone();
2708
2709        let ops = self.text.randomly_undo_redo(rng);
2710        if !ops.is_empty() {
2711            for op in ops {
2712                self.send_operation(Operation::Buffer(op), true, cx);
2713                self.did_edit(&old_version, was_dirty, cx);
2714            }
2715        }
2716    }
2717}
2718
2719impl EventEmitter<BufferEvent> for Buffer {}
2720
2721impl Deref for Buffer {
2722    type Target = TextBuffer;
2723
2724    fn deref(&self) -> &Self::Target {
2725        &self.text
2726    }
2727}
2728
2729impl BufferSnapshot {
2730    /// Returns [`IndentSize`] for a given line that respects user settings and
2731    /// language preferences.
2732    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
2733        indent_size_for_line(self, row)
2734    }
2735
2736    /// Returns [`IndentSize`] for a given position that respects user settings
2737    /// and language preferences.
2738    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &App) -> IndentSize {
2739        let settings = language_settings(
2740            self.language_at(position).map(|l| l.name()),
2741            self.file(),
2742            cx,
2743        );
2744        if settings.hard_tabs {
2745            IndentSize::tab()
2746        } else {
2747            IndentSize::spaces(settings.tab_size.get())
2748        }
2749    }
2750
2751    /// Retrieve the suggested indent size for all of the given rows. The unit of indentation
2752    /// is passed in as `single_indent_size`.
2753    pub fn suggested_indents(
2754        &self,
2755        rows: impl Iterator<Item = u32>,
2756        single_indent_size: IndentSize,
2757    ) -> BTreeMap<u32, IndentSize> {
2758        let mut result = BTreeMap::new();
2759
2760        for row_range in contiguous_ranges(rows, 10) {
2761            let suggestions = match self.suggest_autoindents(row_range.clone()) {
2762                Some(suggestions) => suggestions,
2763                _ => break,
2764            };
2765
2766            for (row, suggestion) in row_range.zip(suggestions) {
2767                let indent_size = if let Some(suggestion) = suggestion {
2768                    result
2769                        .get(&suggestion.basis_row)
2770                        .copied()
2771                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
2772                        .with_delta(suggestion.delta, single_indent_size)
2773                } else {
2774                    self.indent_size_for_line(row)
2775                };
2776
2777                result.insert(row, indent_size);
2778            }
2779        }
2780
2781        result
2782    }
2783
2784    fn suggest_autoindents(
2785        &self,
2786        row_range: Range<u32>,
2787    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
2788        let config = &self.language.as_ref()?.config;
2789        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
2790
2791        // Find the suggested indentation ranges based on the syntax tree.
2792        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
2793        let end = Point::new(row_range.end, 0);
2794        let range = (start..end).to_offset(&self.text);
2795        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2796            Some(&grammar.indents_config.as_ref()?.query)
2797        });
2798        let indent_configs = matches
2799            .grammars()
2800            .iter()
2801            .map(|grammar| grammar.indents_config.as_ref().unwrap())
2802            .collect::<Vec<_>>();
2803
2804        let mut indent_ranges = Vec::<Range<Point>>::new();
2805        let mut outdent_positions = Vec::<Point>::new();
2806        while let Some(mat) = matches.peek() {
2807            let mut start: Option<Point> = None;
2808            let mut end: Option<Point> = None;
2809
2810            let config = &indent_configs[mat.grammar_index];
2811            for capture in mat.captures {
2812                if capture.index == config.indent_capture_ix {
2813                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
2814                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
2815                } else if Some(capture.index) == config.start_capture_ix {
2816                    start = Some(Point::from_ts_point(capture.node.end_position()));
2817                } else if Some(capture.index) == config.end_capture_ix {
2818                    end = Some(Point::from_ts_point(capture.node.start_position()));
2819                } else if Some(capture.index) == config.outdent_capture_ix {
2820                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
2821                }
2822            }
2823
2824            matches.advance();
2825            if let Some((start, end)) = start.zip(end) {
2826                if start.row == end.row {
2827                    continue;
2828                }
2829
2830                let range = start..end;
2831                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
2832                    Err(ix) => indent_ranges.insert(ix, range),
2833                    Ok(ix) => {
2834                        let prev_range = &mut indent_ranges[ix];
2835                        prev_range.end = prev_range.end.max(range.end);
2836                    }
2837                }
2838            }
2839        }
2840
2841        let mut error_ranges = Vec::<Range<Point>>::new();
2842        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2843            grammar.error_query.as_ref()
2844        });
2845        while let Some(mat) = matches.peek() {
2846            let node = mat.captures[0].node;
2847            let start = Point::from_ts_point(node.start_position());
2848            let end = Point::from_ts_point(node.end_position());
2849            let range = start..end;
2850            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
2851                Ok(ix) | Err(ix) => ix,
2852            };
2853            let mut end_ix = ix;
2854            while let Some(existing_range) = error_ranges.get(end_ix) {
2855                if existing_range.end < end {
2856                    end_ix += 1;
2857                } else {
2858                    break;
2859                }
2860            }
2861            error_ranges.splice(ix..end_ix, [range]);
2862            matches.advance();
2863        }
2864
2865        outdent_positions.sort();
2866        for outdent_position in outdent_positions {
2867            // find the innermost indent range containing this outdent_position
2868            // set its end to the outdent position
2869            if let Some(range_to_truncate) = indent_ranges
2870                .iter_mut()
2871                .filter(|indent_range| indent_range.contains(&outdent_position))
2872                .last()
2873            {
2874                range_to_truncate.end = outdent_position;
2875            }
2876        }
2877
2878        // Find the suggested indentation increases and decreased based on regexes.
2879        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
2880        self.for_each_line(
2881            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
2882                ..Point::new(row_range.end, 0),
2883            |row, line| {
2884                if config
2885                    .decrease_indent_pattern
2886                    .as_ref()
2887                    .map_or(false, |regex| regex.is_match(line))
2888                {
2889                    indent_change_rows.push((row, Ordering::Less));
2890                }
2891                if config
2892                    .increase_indent_pattern
2893                    .as_ref()
2894                    .map_or(false, |regex| regex.is_match(line))
2895                {
2896                    indent_change_rows.push((row + 1, Ordering::Greater));
2897                }
2898            },
2899        );
2900
2901        let mut indent_changes = indent_change_rows.into_iter().peekable();
2902        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
2903            prev_non_blank_row.unwrap_or(0)
2904        } else {
2905            row_range.start.saturating_sub(1)
2906        };
2907        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
2908        Some(row_range.map(move |row| {
2909            let row_start = Point::new(row, self.indent_size_for_line(row).len);
2910
2911            let mut indent_from_prev_row = false;
2912            let mut outdent_from_prev_row = false;
2913            let mut outdent_to_row = u32::MAX;
2914            let mut from_regex = false;
2915
2916            while let Some((indent_row, delta)) = indent_changes.peek() {
2917                match indent_row.cmp(&row) {
2918                    Ordering::Equal => match delta {
2919                        Ordering::Less => {
2920                            from_regex = true;
2921                            outdent_from_prev_row = true
2922                        }
2923                        Ordering::Greater => {
2924                            indent_from_prev_row = true;
2925                            from_regex = true
2926                        }
2927                        _ => {}
2928                    },
2929
2930                    Ordering::Greater => break,
2931                    Ordering::Less => {}
2932                }
2933
2934                indent_changes.next();
2935            }
2936
2937            for range in &indent_ranges {
2938                if range.start.row >= row {
2939                    break;
2940                }
2941                if range.start.row == prev_row && range.end > row_start {
2942                    indent_from_prev_row = true;
2943                }
2944                if range.end > prev_row_start && range.end <= row_start {
2945                    outdent_to_row = outdent_to_row.min(range.start.row);
2946                }
2947            }
2948
2949            let within_error = error_ranges
2950                .iter()
2951                .any(|e| e.start.row < row && e.end > row_start);
2952
2953            let suggestion = if outdent_to_row == prev_row
2954                || (outdent_from_prev_row && indent_from_prev_row)
2955            {
2956                Some(IndentSuggestion {
2957                    basis_row: prev_row,
2958                    delta: Ordering::Equal,
2959                    within_error: within_error && !from_regex,
2960                })
2961            } else if indent_from_prev_row {
2962                Some(IndentSuggestion {
2963                    basis_row: prev_row,
2964                    delta: Ordering::Greater,
2965                    within_error: within_error && !from_regex,
2966                })
2967            } else if outdent_to_row < prev_row {
2968                Some(IndentSuggestion {
2969                    basis_row: outdent_to_row,
2970                    delta: Ordering::Equal,
2971                    within_error: within_error && !from_regex,
2972                })
2973            } else if outdent_from_prev_row {
2974                Some(IndentSuggestion {
2975                    basis_row: prev_row,
2976                    delta: Ordering::Less,
2977                    within_error: within_error && !from_regex,
2978                })
2979            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
2980            {
2981                Some(IndentSuggestion {
2982                    basis_row: prev_row,
2983                    delta: Ordering::Equal,
2984                    within_error: within_error && !from_regex,
2985                })
2986            } else {
2987                None
2988            };
2989
2990            prev_row = row;
2991            prev_row_start = row_start;
2992            suggestion
2993        }))
2994    }
2995
2996    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
2997        while row > 0 {
2998            row -= 1;
2999            if !self.is_line_blank(row) {
3000                return Some(row);
3001            }
3002        }
3003        None
3004    }
3005
3006    fn get_highlights(&self, range: Range<usize>) -> (SyntaxMapCaptures, Vec<HighlightMap>) {
3007        let captures = self.syntax.captures(range, &self.text, |grammar| {
3008            grammar.highlights_query.as_ref()
3009        });
3010        let highlight_maps = captures
3011            .grammars()
3012            .iter()
3013            .map(|grammar| grammar.highlight_map())
3014            .collect();
3015        (captures, highlight_maps)
3016    }
3017
3018    /// Iterates over chunks of text in the given range of the buffer. Text is chunked
3019    /// in an arbitrary way due to being stored in a [`Rope`](text::Rope). The text is also
3020    /// returned in chunks where each chunk has a single syntax highlighting style and
3021    /// diagnostic status.
3022    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
3023        let range = range.start.to_offset(self)..range.end.to_offset(self);
3024
3025        let mut syntax = None;
3026        if language_aware {
3027            syntax = Some(self.get_highlights(range.clone()));
3028        }
3029        // We want to look at diagnostic spans only when iterating over language-annotated chunks.
3030        let diagnostics = language_aware;
3031        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostics, Some(self))
3032    }
3033
3034    pub fn highlighted_text_for_range<T: ToOffset>(
3035        &self,
3036        range: Range<T>,
3037        override_style: Option<HighlightStyle>,
3038        syntax_theme: &SyntaxTheme,
3039    ) -> HighlightedText {
3040        HighlightedText::from_buffer_range(
3041            range,
3042            &self.text,
3043            &self.syntax,
3044            override_style,
3045            syntax_theme,
3046        )
3047    }
3048
3049    /// Invokes the given callback for each line of text in the given range of the buffer.
3050    /// Uses callback to avoid allocating a string for each line.
3051    fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
3052        let mut line = String::new();
3053        let mut row = range.start.row;
3054        for chunk in self
3055            .as_rope()
3056            .chunks_in_range(range.to_offset(self))
3057            .chain(["\n"])
3058        {
3059            for (newline_ix, text) in chunk.split('\n').enumerate() {
3060                if newline_ix > 0 {
3061                    callback(row, &line);
3062                    row += 1;
3063                    line.clear();
3064                }
3065                line.push_str(text);
3066            }
3067        }
3068    }
3069
3070    /// Iterates over every [`SyntaxLayer`] in the buffer.
3071    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayer> + '_ {
3072        self.syntax
3073            .layers_for_range(0..self.len(), &self.text, true)
3074    }
3075
3076    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayer> {
3077        let offset = position.to_offset(self);
3078        self.syntax
3079            .layers_for_range(offset..offset, &self.text, false)
3080            .filter(|l| l.node().end_byte() > offset)
3081            .last()
3082    }
3083
3084    /// Returns the main [`Language`].
3085    pub fn language(&self) -> Option<&Arc<Language>> {
3086        self.language.as_ref()
3087    }
3088
3089    /// Returns the [`Language`] at the given location.
3090    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
3091        self.syntax_layer_at(position)
3092            .map(|info| info.language)
3093            .or(self.language.as_ref())
3094    }
3095
3096    /// Returns the settings for the language at the given location.
3097    pub fn settings_at<'a, D: ToOffset>(
3098        &'a self,
3099        position: D,
3100        cx: &'a App,
3101    ) -> Cow<'a, LanguageSettings> {
3102        language_settings(
3103            self.language_at(position).map(|l| l.name()),
3104            self.file.as_ref(),
3105            cx,
3106        )
3107    }
3108
3109    pub fn char_classifier_at<T: ToOffset>(&self, point: T) -> CharClassifier {
3110        CharClassifier::new(self.language_scope_at(point))
3111    }
3112
3113    /// Returns the [`LanguageScope`] at the given location.
3114    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
3115        let offset = position.to_offset(self);
3116        let mut scope = None;
3117        let mut smallest_range: Option<Range<usize>> = None;
3118
3119        // Use the layer that has the smallest node intersecting the given point.
3120        for layer in self
3121            .syntax
3122            .layers_for_range(offset..offset, &self.text, false)
3123        {
3124            let mut cursor = layer.node().walk();
3125
3126            let mut range = None;
3127            loop {
3128                let child_range = cursor.node().byte_range();
3129                if !child_range.to_inclusive().contains(&offset) {
3130                    break;
3131                }
3132
3133                range = Some(child_range);
3134                if cursor.goto_first_child_for_byte(offset).is_none() {
3135                    break;
3136                }
3137            }
3138
3139            if let Some(range) = range {
3140                if smallest_range
3141                    .as_ref()
3142                    .map_or(true, |smallest_range| range.len() < smallest_range.len())
3143                {
3144                    smallest_range = Some(range);
3145                    scope = Some(LanguageScope {
3146                        language: layer.language.clone(),
3147                        override_id: layer.override_id(offset, &self.text),
3148                    });
3149                }
3150            }
3151        }
3152
3153        scope.or_else(|| {
3154            self.language.clone().map(|language| LanguageScope {
3155                language,
3156                override_id: None,
3157            })
3158        })
3159    }
3160
3161    /// Returns a tuple of the range and character kind of the word
3162    /// surrounding the given position.
3163    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
3164        let mut start = start.to_offset(self);
3165        let mut end = start;
3166        let mut next_chars = self.chars_at(start).peekable();
3167        let mut prev_chars = self.reversed_chars_at(start).peekable();
3168
3169        let classifier = self.char_classifier_at(start);
3170        let word_kind = cmp::max(
3171            prev_chars.peek().copied().map(|c| classifier.kind(c)),
3172            next_chars.peek().copied().map(|c| classifier.kind(c)),
3173        );
3174
3175        for ch in prev_chars {
3176            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3177                start -= ch.len_utf8();
3178            } else {
3179                break;
3180            }
3181        }
3182
3183        for ch in next_chars {
3184            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3185                end += ch.len_utf8();
3186            } else {
3187                break;
3188            }
3189        }
3190
3191        (start..end, word_kind)
3192    }
3193
3194    /// Returns the closest syntax node enclosing the given range.
3195    pub fn syntax_ancestor<'a, T: ToOffset>(
3196        &'a self,
3197        range: Range<T>,
3198    ) -> Option<tree_sitter::Node<'a>> {
3199        let range = range.start.to_offset(self)..range.end.to_offset(self);
3200        let mut result: Option<tree_sitter::Node<'a>> = None;
3201        'outer: for layer in self
3202            .syntax
3203            .layers_for_range(range.clone(), &self.text, true)
3204        {
3205            let mut cursor = layer.node().walk();
3206
3207            // Descend to the first leaf that touches the start of the range,
3208            // and if the range is non-empty, extends beyond the start.
3209            while cursor.goto_first_child_for_byte(range.start).is_some() {
3210                if !range.is_empty() && cursor.node().end_byte() == range.start {
3211                    cursor.goto_next_sibling();
3212                }
3213            }
3214
3215            // Ascend to the smallest ancestor that strictly contains the range.
3216            loop {
3217                let node_range = cursor.node().byte_range();
3218                if node_range.start <= range.start
3219                    && node_range.end >= range.end
3220                    && node_range.len() > range.len()
3221                {
3222                    break;
3223                }
3224                if !cursor.goto_parent() {
3225                    continue 'outer;
3226                }
3227            }
3228
3229            let left_node = cursor.node();
3230            let mut layer_result = left_node;
3231
3232            // For an empty range, try to find another node immediately to the right of the range.
3233            if left_node.end_byte() == range.start {
3234                let mut right_node = None;
3235                while !cursor.goto_next_sibling() {
3236                    if !cursor.goto_parent() {
3237                        break;
3238                    }
3239                }
3240
3241                while cursor.node().start_byte() == range.start {
3242                    right_node = Some(cursor.node());
3243                    if !cursor.goto_first_child() {
3244                        break;
3245                    }
3246                }
3247
3248                // If there is a candidate node on both sides of the (empty) range, then
3249                // decide between the two by favoring a named node over an anonymous token.
3250                // If both nodes are the same in that regard, favor the right one.
3251                if let Some(right_node) = right_node {
3252                    if right_node.is_named() || !left_node.is_named() {
3253                        layer_result = right_node;
3254                    }
3255                }
3256            }
3257
3258            if let Some(previous_result) = &result {
3259                if previous_result.byte_range().len() < layer_result.byte_range().len() {
3260                    continue;
3261                }
3262            }
3263            result = Some(layer_result);
3264        }
3265
3266        result
3267    }
3268
3269    /// Returns the outline for the buffer.
3270    ///
3271    /// This method allows passing an optional [`SyntaxTheme`] to
3272    /// syntax-highlight the returned symbols.
3273    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
3274        self.outline_items_containing(0..self.len(), true, theme)
3275            .map(Outline::new)
3276    }
3277
3278    /// Returns all the symbols that contain the given position.
3279    ///
3280    /// This method allows passing an optional [`SyntaxTheme`] to
3281    /// syntax-highlight the returned symbols.
3282    pub fn symbols_containing<T: ToOffset>(
3283        &self,
3284        position: T,
3285        theme: Option<&SyntaxTheme>,
3286    ) -> Option<Vec<OutlineItem<Anchor>>> {
3287        let position = position.to_offset(self);
3288        let mut items = self.outline_items_containing(
3289            position.saturating_sub(1)..self.len().min(position + 1),
3290            false,
3291            theme,
3292        )?;
3293        let mut prev_depth = None;
3294        items.retain(|item| {
3295            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
3296            prev_depth = Some(item.depth);
3297            result
3298        });
3299        Some(items)
3300    }
3301
3302    pub fn outline_range_containing<T: ToOffset>(&self, range: Range<T>) -> Option<Range<Point>> {
3303        let range = range.to_offset(self);
3304        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3305            grammar.outline_config.as_ref().map(|c| &c.query)
3306        });
3307        let configs = matches
3308            .grammars()
3309            .iter()
3310            .map(|g| g.outline_config.as_ref().unwrap())
3311            .collect::<Vec<_>>();
3312
3313        while let Some(mat) = matches.peek() {
3314            let config = &configs[mat.grammar_index];
3315            let containing_item_node = maybe!({
3316                let item_node = mat.captures.iter().find_map(|cap| {
3317                    if cap.index == config.item_capture_ix {
3318                        Some(cap.node)
3319                    } else {
3320                        None
3321                    }
3322                })?;
3323
3324                let item_byte_range = item_node.byte_range();
3325                if item_byte_range.end < range.start || item_byte_range.start > range.end {
3326                    None
3327                } else {
3328                    Some(item_node)
3329                }
3330            });
3331
3332            if let Some(item_node) = containing_item_node {
3333                return Some(
3334                    Point::from_ts_point(item_node.start_position())
3335                        ..Point::from_ts_point(item_node.end_position()),
3336                );
3337            }
3338
3339            matches.advance();
3340        }
3341        None
3342    }
3343
3344    pub fn outline_items_containing<T: ToOffset>(
3345        &self,
3346        range: Range<T>,
3347        include_extra_context: bool,
3348        theme: Option<&SyntaxTheme>,
3349    ) -> Option<Vec<OutlineItem<Anchor>>> {
3350        let range = range.to_offset(self);
3351        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3352            grammar.outline_config.as_ref().map(|c| &c.query)
3353        });
3354        let configs = matches
3355            .grammars()
3356            .iter()
3357            .map(|g| g.outline_config.as_ref().unwrap())
3358            .collect::<Vec<_>>();
3359
3360        let mut items = Vec::new();
3361        let mut annotation_row_ranges: Vec<Range<u32>> = Vec::new();
3362        while let Some(mat) = matches.peek() {
3363            let config = &configs[mat.grammar_index];
3364            if let Some(item) =
3365                self.next_outline_item(config, &mat, &range, include_extra_context, theme)
3366            {
3367                items.push(item);
3368            } else if let Some(capture) = mat
3369                .captures
3370                .iter()
3371                .find(|capture| Some(capture.index) == config.annotation_capture_ix)
3372            {
3373                let capture_range = capture.node.start_position()..capture.node.end_position();
3374                let mut capture_row_range =
3375                    capture_range.start.row as u32..capture_range.end.row as u32;
3376                if capture_range.end.row > capture_range.start.row && capture_range.end.column == 0
3377                {
3378                    capture_row_range.end -= 1;
3379                }
3380                if let Some(last_row_range) = annotation_row_ranges.last_mut() {
3381                    if last_row_range.end >= capture_row_range.start.saturating_sub(1) {
3382                        last_row_range.end = capture_row_range.end;
3383                    } else {
3384                        annotation_row_ranges.push(capture_row_range);
3385                    }
3386                } else {
3387                    annotation_row_ranges.push(capture_row_range);
3388                }
3389            }
3390            matches.advance();
3391        }
3392
3393        items.sort_by_key(|item| (item.range.start, Reverse(item.range.end)));
3394
3395        // Assign depths based on containment relationships and convert to anchors.
3396        let mut item_ends_stack = Vec::<Point>::new();
3397        let mut anchor_items = Vec::new();
3398        let mut annotation_row_ranges = annotation_row_ranges.into_iter().peekable();
3399        for item in items {
3400            while let Some(last_end) = item_ends_stack.last().copied() {
3401                if last_end < item.range.end {
3402                    item_ends_stack.pop();
3403                } else {
3404                    break;
3405                }
3406            }
3407
3408            let mut annotation_row_range = None;
3409            while let Some(next_annotation_row_range) = annotation_row_ranges.peek() {
3410                let row_preceding_item = item.range.start.row.saturating_sub(1);
3411                if next_annotation_row_range.end < row_preceding_item {
3412                    annotation_row_ranges.next();
3413                } else {
3414                    if next_annotation_row_range.end == row_preceding_item {
3415                        annotation_row_range = Some(next_annotation_row_range.clone());
3416                        annotation_row_ranges.next();
3417                    }
3418                    break;
3419                }
3420            }
3421
3422            anchor_items.push(OutlineItem {
3423                depth: item_ends_stack.len(),
3424                range: self.anchor_after(item.range.start)..self.anchor_before(item.range.end),
3425                text: item.text,
3426                highlight_ranges: item.highlight_ranges,
3427                name_ranges: item.name_ranges,
3428                body_range: item.body_range.map(|body_range| {
3429                    self.anchor_after(body_range.start)..self.anchor_before(body_range.end)
3430                }),
3431                annotation_range: annotation_row_range.map(|annotation_range| {
3432                    self.anchor_after(Point::new(annotation_range.start, 0))
3433                        ..self.anchor_before(Point::new(
3434                            annotation_range.end,
3435                            self.line_len(annotation_range.end),
3436                        ))
3437                }),
3438            });
3439            item_ends_stack.push(item.range.end);
3440        }
3441
3442        Some(anchor_items)
3443    }
3444
3445    fn next_outline_item(
3446        &self,
3447        config: &OutlineConfig,
3448        mat: &SyntaxMapMatch,
3449        range: &Range<usize>,
3450        include_extra_context: bool,
3451        theme: Option<&SyntaxTheme>,
3452    ) -> Option<OutlineItem<Point>> {
3453        let item_node = mat.captures.iter().find_map(|cap| {
3454            if cap.index == config.item_capture_ix {
3455                Some(cap.node)
3456            } else {
3457                None
3458            }
3459        })?;
3460
3461        let item_byte_range = item_node.byte_range();
3462        if item_byte_range.end < range.start || item_byte_range.start > range.end {
3463            return None;
3464        }
3465        let item_point_range = Point::from_ts_point(item_node.start_position())
3466            ..Point::from_ts_point(item_node.end_position());
3467
3468        let mut open_point = None;
3469        let mut close_point = None;
3470        let mut buffer_ranges = Vec::new();
3471        for capture in mat.captures {
3472            let node_is_name;
3473            if capture.index == config.name_capture_ix {
3474                node_is_name = true;
3475            } else if Some(capture.index) == config.context_capture_ix
3476                || (Some(capture.index) == config.extra_context_capture_ix && include_extra_context)
3477            {
3478                node_is_name = false;
3479            } else {
3480                if Some(capture.index) == config.open_capture_ix {
3481                    open_point = Some(Point::from_ts_point(capture.node.end_position()));
3482                } else if Some(capture.index) == config.close_capture_ix {
3483                    close_point = Some(Point::from_ts_point(capture.node.start_position()));
3484                }
3485
3486                continue;
3487            }
3488
3489            let mut range = capture.node.start_byte()..capture.node.end_byte();
3490            let start = capture.node.start_position();
3491            if capture.node.end_position().row > start.row {
3492                range.end = range.start + self.line_len(start.row as u32) as usize - start.column;
3493            }
3494
3495            if !range.is_empty() {
3496                buffer_ranges.push((range, node_is_name));
3497            }
3498        }
3499        if buffer_ranges.is_empty() {
3500            return None;
3501        }
3502        let mut text = String::new();
3503        let mut highlight_ranges = Vec::new();
3504        let mut name_ranges = Vec::new();
3505        let mut chunks = self.chunks(
3506            buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
3507            true,
3508        );
3509        let mut last_buffer_range_end = 0;
3510
3511        for (buffer_range, is_name) in buffer_ranges {
3512            let space_added = !text.is_empty() && buffer_range.start > last_buffer_range_end;
3513            if space_added {
3514                text.push(' ');
3515            }
3516            let before_append_len = text.len();
3517            let mut offset = buffer_range.start;
3518            chunks.seek(buffer_range.clone());
3519            for mut chunk in chunks.by_ref() {
3520                if chunk.text.len() > buffer_range.end - offset {
3521                    chunk.text = &chunk.text[0..(buffer_range.end - offset)];
3522                    offset = buffer_range.end;
3523                } else {
3524                    offset += chunk.text.len();
3525                }
3526                let style = chunk
3527                    .syntax_highlight_id
3528                    .zip(theme)
3529                    .and_then(|(highlight, theme)| highlight.style(theme));
3530                if let Some(style) = style {
3531                    let start = text.len();
3532                    let end = start + chunk.text.len();
3533                    highlight_ranges.push((start..end, style));
3534                }
3535                text.push_str(chunk.text);
3536                if offset >= buffer_range.end {
3537                    break;
3538                }
3539            }
3540            if is_name {
3541                let after_append_len = text.len();
3542                let start = if space_added && !name_ranges.is_empty() {
3543                    before_append_len - 1
3544                } else {
3545                    before_append_len
3546                };
3547                name_ranges.push(start..after_append_len);
3548            }
3549            last_buffer_range_end = buffer_range.end;
3550        }
3551
3552        Some(OutlineItem {
3553            depth: 0, // We'll calculate the depth later
3554            range: item_point_range,
3555            text,
3556            highlight_ranges,
3557            name_ranges,
3558            body_range: open_point.zip(close_point).map(|(start, end)| start..end),
3559            annotation_range: None,
3560        })
3561    }
3562
3563    pub fn function_body_fold_ranges<T: ToOffset>(
3564        &self,
3565        within: Range<T>,
3566    ) -> impl Iterator<Item = Range<usize>> + '_ {
3567        self.text_object_ranges(within, TreeSitterOptions::default())
3568            .filter_map(|(range, obj)| (obj == TextObject::InsideFunction).then_some(range))
3569    }
3570
3571    /// For each grammar in the language, runs the provided
3572    /// [`tree_sitter::Query`] against the given range.
3573    pub fn matches(
3574        &self,
3575        range: Range<usize>,
3576        query: fn(&Grammar) -> Option<&tree_sitter::Query>,
3577    ) -> SyntaxMapMatches {
3578        self.syntax.matches(range, self, query)
3579    }
3580
3581    pub fn all_bracket_ranges(
3582        &self,
3583        range: Range<usize>,
3584    ) -> impl Iterator<Item = BracketMatch> + '_ {
3585        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3586            grammar.brackets_config.as_ref().map(|c| &c.query)
3587        });
3588        let configs = matches
3589            .grammars()
3590            .iter()
3591            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
3592            .collect::<Vec<_>>();
3593
3594        iter::from_fn(move || {
3595            while let Some(mat) = matches.peek() {
3596                let mut open = None;
3597                let mut close = None;
3598                let config = &configs[mat.grammar_index];
3599                let pattern = &config.patterns[mat.pattern_index];
3600                for capture in mat.captures {
3601                    if capture.index == config.open_capture_ix {
3602                        open = Some(capture.node.byte_range());
3603                    } else if capture.index == config.close_capture_ix {
3604                        close = Some(capture.node.byte_range());
3605                    }
3606                }
3607
3608                matches.advance();
3609
3610                let Some((open_range, close_range)) = open.zip(close) else {
3611                    continue;
3612                };
3613
3614                let bracket_range = open_range.start..=close_range.end;
3615                if !bracket_range.overlaps(&range) {
3616                    continue;
3617                }
3618
3619                return Some(BracketMatch {
3620                    open_range,
3621                    close_range,
3622                    newline_only: pattern.newline_only,
3623                });
3624            }
3625            None
3626        })
3627    }
3628
3629    /// Returns bracket range pairs overlapping or adjacent to `range`
3630    pub fn bracket_ranges<T: ToOffset>(
3631        &self,
3632        range: Range<T>,
3633    ) -> impl Iterator<Item = BracketMatch> + '_ {
3634        // Find bracket pairs that *inclusively* contain the given range.
3635        let range = range.start.to_offset(self).saturating_sub(1)
3636            ..self.len().min(range.end.to_offset(self) + 1);
3637        self.all_bracket_ranges(range)
3638            .filter(|pair| !pair.newline_only)
3639    }
3640
3641    pub fn text_object_ranges<T: ToOffset>(
3642        &self,
3643        range: Range<T>,
3644        options: TreeSitterOptions,
3645    ) -> impl Iterator<Item = (Range<usize>, TextObject)> + '_ {
3646        let range = range.start.to_offset(self).saturating_sub(1)
3647            ..self.len().min(range.end.to_offset(self) + 1);
3648
3649        let mut matches =
3650            self.syntax
3651                .matches_with_options(range.clone(), &self.text, options, |grammar| {
3652                    grammar.text_object_config.as_ref().map(|c| &c.query)
3653                });
3654
3655        let configs = matches
3656            .grammars()
3657            .iter()
3658            .map(|grammar| grammar.text_object_config.as_ref())
3659            .collect::<Vec<_>>();
3660
3661        let mut captures = Vec::<(Range<usize>, TextObject)>::new();
3662
3663        iter::from_fn(move || loop {
3664            while let Some(capture) = captures.pop() {
3665                if capture.0.overlaps(&range) {
3666                    return Some(capture);
3667                }
3668            }
3669
3670            let mat = matches.peek()?;
3671
3672            let Some(config) = configs[mat.grammar_index].as_ref() else {
3673                matches.advance();
3674                continue;
3675            };
3676
3677            for capture in mat.captures {
3678                let Some(ix) = config
3679                    .text_objects_by_capture_ix
3680                    .binary_search_by_key(&capture.index, |e| e.0)
3681                    .ok()
3682                else {
3683                    continue;
3684                };
3685                let text_object = config.text_objects_by_capture_ix[ix].1;
3686                let byte_range = capture.node.byte_range();
3687
3688                let mut found = false;
3689                for (range, existing) in captures.iter_mut() {
3690                    if existing == &text_object {
3691                        range.start = range.start.min(byte_range.start);
3692                        range.end = range.end.max(byte_range.end);
3693                        found = true;
3694                        break;
3695                    }
3696                }
3697
3698                if !found {
3699                    captures.push((byte_range, text_object));
3700                }
3701            }
3702
3703            matches.advance();
3704        })
3705    }
3706
3707    /// Returns enclosing bracket ranges containing the given range
3708    pub fn enclosing_bracket_ranges<T: ToOffset>(
3709        &self,
3710        range: Range<T>,
3711    ) -> impl Iterator<Item = BracketMatch> + '_ {
3712        let range = range.start.to_offset(self)..range.end.to_offset(self);
3713
3714        self.bracket_ranges(range.clone()).filter(move |pair| {
3715            pair.open_range.start <= range.start && pair.close_range.end >= range.end
3716        })
3717    }
3718
3719    /// Returns the smallest enclosing bracket ranges containing the given range or None if no brackets contain range
3720    ///
3721    /// Can optionally pass a range_filter to filter the ranges of brackets to consider
3722    pub fn innermost_enclosing_bracket_ranges<T: ToOffset>(
3723        &self,
3724        range: Range<T>,
3725        range_filter: Option<&dyn Fn(Range<usize>, Range<usize>) -> bool>,
3726    ) -> Option<(Range<usize>, Range<usize>)> {
3727        let range = range.start.to_offset(self)..range.end.to_offset(self);
3728
3729        // Get the ranges of the innermost pair of brackets.
3730        let mut result: Option<(Range<usize>, Range<usize>)> = None;
3731
3732        for pair in self.enclosing_bracket_ranges(range.clone()) {
3733            if let Some(range_filter) = range_filter {
3734                if !range_filter(pair.open_range.clone(), pair.close_range.clone()) {
3735                    continue;
3736                }
3737            }
3738
3739            let len = pair.close_range.end - pair.open_range.start;
3740
3741            if let Some((existing_open, existing_close)) = &result {
3742                let existing_len = existing_close.end - existing_open.start;
3743                if len > existing_len {
3744                    continue;
3745                }
3746            }
3747
3748            result = Some((pair.open_range, pair.close_range));
3749        }
3750
3751        result
3752    }
3753
3754    /// Returns anchor ranges for any matches of the redaction query.
3755    /// The buffer can be associated with multiple languages, and the redaction query associated with each
3756    /// will be run on the relevant section of the buffer.
3757    pub fn redacted_ranges<T: ToOffset>(
3758        &self,
3759        range: Range<T>,
3760    ) -> impl Iterator<Item = Range<usize>> + '_ {
3761        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3762        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3763            grammar
3764                .redactions_config
3765                .as_ref()
3766                .map(|config| &config.query)
3767        });
3768
3769        let configs = syntax_matches
3770            .grammars()
3771            .iter()
3772            .map(|grammar| grammar.redactions_config.as_ref())
3773            .collect::<Vec<_>>();
3774
3775        iter::from_fn(move || {
3776            let redacted_range = syntax_matches
3777                .peek()
3778                .and_then(|mat| {
3779                    configs[mat.grammar_index].and_then(|config| {
3780                        mat.captures
3781                            .iter()
3782                            .find(|capture| capture.index == config.redaction_capture_ix)
3783                    })
3784                })
3785                .map(|mat| mat.node.byte_range());
3786            syntax_matches.advance();
3787            redacted_range
3788        })
3789    }
3790
3791    pub fn injections_intersecting_range<T: ToOffset>(
3792        &self,
3793        range: Range<T>,
3794    ) -> impl Iterator<Item = (Range<usize>, &Arc<Language>)> + '_ {
3795        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3796
3797        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3798            grammar
3799                .injection_config
3800                .as_ref()
3801                .map(|config| &config.query)
3802        });
3803
3804        let configs = syntax_matches
3805            .grammars()
3806            .iter()
3807            .map(|grammar| grammar.injection_config.as_ref())
3808            .collect::<Vec<_>>();
3809
3810        iter::from_fn(move || {
3811            let ranges = syntax_matches.peek().and_then(|mat| {
3812                let config = &configs[mat.grammar_index]?;
3813                let content_capture_range = mat.captures.iter().find_map(|capture| {
3814                    if capture.index == config.content_capture_ix {
3815                        Some(capture.node.byte_range())
3816                    } else {
3817                        None
3818                    }
3819                })?;
3820                let language = self.language_at(content_capture_range.start)?;
3821                Some((content_capture_range, language))
3822            });
3823            syntax_matches.advance();
3824            ranges
3825        })
3826    }
3827
3828    pub fn runnable_ranges(
3829        &self,
3830        offset_range: Range<usize>,
3831    ) -> impl Iterator<Item = RunnableRange> + '_ {
3832        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3833            grammar.runnable_config.as_ref().map(|config| &config.query)
3834        });
3835
3836        let test_configs = syntax_matches
3837            .grammars()
3838            .iter()
3839            .map(|grammar| grammar.runnable_config.as_ref())
3840            .collect::<Vec<_>>();
3841
3842        iter::from_fn(move || loop {
3843            let mat = syntax_matches.peek()?;
3844
3845            let test_range = test_configs[mat.grammar_index].and_then(|test_configs| {
3846                let mut run_range = None;
3847                let full_range = mat.captures.iter().fold(
3848                    Range {
3849                        start: usize::MAX,
3850                        end: 0,
3851                    },
3852                    |mut acc, next| {
3853                        let byte_range = next.node.byte_range();
3854                        if acc.start > byte_range.start {
3855                            acc.start = byte_range.start;
3856                        }
3857                        if acc.end < byte_range.end {
3858                            acc.end = byte_range.end;
3859                        }
3860                        acc
3861                    },
3862                );
3863                if full_range.start > full_range.end {
3864                    // We did not find a full spanning range of this match.
3865                    return None;
3866                }
3867                let extra_captures: SmallVec<[_; 1]> =
3868                    SmallVec::from_iter(mat.captures.iter().filter_map(|capture| {
3869                        test_configs
3870                            .extra_captures
3871                            .get(capture.index as usize)
3872                            .cloned()
3873                            .and_then(|tag_name| match tag_name {
3874                                RunnableCapture::Named(name) => {
3875                                    Some((capture.node.byte_range(), name))
3876                                }
3877                                RunnableCapture::Run => {
3878                                    let _ = run_range.insert(capture.node.byte_range());
3879                                    None
3880                                }
3881                            })
3882                    }));
3883                let run_range = run_range?;
3884                let tags = test_configs
3885                    .query
3886                    .property_settings(mat.pattern_index)
3887                    .iter()
3888                    .filter_map(|property| {
3889                        if *property.key == *"tag" {
3890                            property
3891                                .value
3892                                .as_ref()
3893                                .map(|value| RunnableTag(value.to_string().into()))
3894                        } else {
3895                            None
3896                        }
3897                    })
3898                    .collect();
3899                let extra_captures = extra_captures
3900                    .into_iter()
3901                    .map(|(range, name)| {
3902                        (
3903                            name.to_string(),
3904                            self.text_for_range(range.clone()).collect::<String>(),
3905                        )
3906                    })
3907                    .collect();
3908                // All tags should have the same range.
3909                Some(RunnableRange {
3910                    run_range,
3911                    full_range,
3912                    runnable: Runnable {
3913                        tags,
3914                        language: mat.language,
3915                        buffer: self.remote_id(),
3916                    },
3917                    extra_captures,
3918                    buffer_id: self.remote_id(),
3919                })
3920            });
3921
3922            syntax_matches.advance();
3923            if test_range.is_some() {
3924                // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
3925                // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
3926                return test_range;
3927            }
3928        })
3929    }
3930
3931    /// Returns selections for remote peers intersecting the given range.
3932    #[allow(clippy::type_complexity)]
3933    pub fn selections_in_range(
3934        &self,
3935        range: Range<Anchor>,
3936        include_local: bool,
3937    ) -> impl Iterator<
3938        Item = (
3939            ReplicaId,
3940            bool,
3941            CursorShape,
3942            impl Iterator<Item = &Selection<Anchor>> + '_,
3943        ),
3944    > + '_ {
3945        self.remote_selections
3946            .iter()
3947            .filter(move |(replica_id, set)| {
3948                (include_local || **replica_id != self.text.replica_id())
3949                    && !set.selections.is_empty()
3950            })
3951            .map(move |(replica_id, set)| {
3952                let start_ix = match set.selections.binary_search_by(|probe| {
3953                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
3954                }) {
3955                    Ok(ix) | Err(ix) => ix,
3956                };
3957                let end_ix = match set.selections.binary_search_by(|probe| {
3958                    probe.start.cmp(&range.end, self).then(Ordering::Less)
3959                }) {
3960                    Ok(ix) | Err(ix) => ix,
3961                };
3962
3963                (
3964                    *replica_id,
3965                    set.line_mode,
3966                    set.cursor_shape,
3967                    set.selections[start_ix..end_ix].iter(),
3968                )
3969            })
3970    }
3971
3972    /// Returns if the buffer contains any diagnostics.
3973    pub fn has_diagnostics(&self) -> bool {
3974        !self.diagnostics.is_empty()
3975    }
3976
3977    /// Returns all the diagnostics intersecting the given range.
3978    pub fn diagnostics_in_range<'a, T, O>(
3979        &'a self,
3980        search_range: Range<T>,
3981        reversed: bool,
3982    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
3983    where
3984        T: 'a + Clone + ToOffset,
3985        O: 'a + FromAnchor,
3986    {
3987        let mut iterators: Vec<_> = self
3988            .diagnostics
3989            .iter()
3990            .map(|(_, collection)| {
3991                collection
3992                    .range::<T, text::Anchor>(search_range.clone(), self, true, reversed)
3993                    .peekable()
3994            })
3995            .collect();
3996
3997        std::iter::from_fn(move || {
3998            let (next_ix, _) = iterators
3999                .iter_mut()
4000                .enumerate()
4001                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
4002                .min_by(|(_, a), (_, b)| {
4003                    let cmp = a
4004                        .range
4005                        .start
4006                        .cmp(&b.range.start, self)
4007                        // when range is equal, sort by diagnostic severity
4008                        .then(a.diagnostic.severity.cmp(&b.diagnostic.severity))
4009                        // and stabilize order with group_id
4010                        .then(a.diagnostic.group_id.cmp(&b.diagnostic.group_id));
4011                    if reversed {
4012                        cmp.reverse()
4013                    } else {
4014                        cmp
4015                    }
4016                })?;
4017            iterators[next_ix]
4018                .next()
4019                .map(|DiagnosticEntry { range, diagnostic }| DiagnosticEntry {
4020                    diagnostic,
4021                    range: FromAnchor::from_anchor(&range.start, self)
4022                        ..FromAnchor::from_anchor(&range.end, self),
4023                })
4024        })
4025    }
4026
4027    /// Returns all the diagnostic groups associated with the given
4028    /// language server ID. If no language server ID is provided,
4029    /// all diagnostics groups are returned.
4030    pub fn diagnostic_groups(
4031        &self,
4032        language_server_id: Option<LanguageServerId>,
4033    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
4034        let mut groups = Vec::new();
4035
4036        if let Some(language_server_id) = language_server_id {
4037            if let Ok(ix) = self
4038                .diagnostics
4039                .binary_search_by_key(&language_server_id, |e| e.0)
4040            {
4041                self.diagnostics[ix]
4042                    .1
4043                    .groups(language_server_id, &mut groups, self);
4044            }
4045        } else {
4046            for (language_server_id, diagnostics) in self.diagnostics.iter() {
4047                diagnostics.groups(*language_server_id, &mut groups, self);
4048            }
4049        }
4050
4051        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
4052            let a_start = &group_a.entries[group_a.primary_ix].range.start;
4053            let b_start = &group_b.entries[group_b.primary_ix].range.start;
4054            a_start.cmp(b_start, self).then_with(|| id_a.cmp(id_b))
4055        });
4056
4057        groups
4058    }
4059
4060    /// Returns an iterator over the diagnostics for the given group.
4061    pub fn diagnostic_group<O>(
4062        &self,
4063        group_id: usize,
4064    ) -> impl Iterator<Item = DiagnosticEntry<O>> + '_
4065    where
4066        O: FromAnchor + 'static,
4067    {
4068        self.diagnostics
4069            .iter()
4070            .flat_map(move |(_, set)| set.group(group_id, self))
4071    }
4072
4073    /// An integer version number that accounts for all updates besides
4074    /// the buffer's text itself (which is versioned via a version vector).
4075    pub fn non_text_state_update_count(&self) -> usize {
4076        self.non_text_state_update_count
4077    }
4078
4079    /// Returns a snapshot of underlying file.
4080    pub fn file(&self) -> Option<&Arc<dyn File>> {
4081        self.file.as_ref()
4082    }
4083
4084    /// Resolves the file path (relative to the worktree root) associated with the underlying file.
4085    pub fn resolve_file_path(&self, cx: &App, include_root: bool) -> Option<PathBuf> {
4086        if let Some(file) = self.file() {
4087            if file.path().file_name().is_none() || include_root {
4088                Some(file.full_path(cx))
4089            } else {
4090                Some(file.path().to_path_buf())
4091            }
4092        } else {
4093            None
4094        }
4095    }
4096}
4097
4098fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
4099    indent_size_for_text(text.chars_at(Point::new(row, 0)))
4100}
4101
4102fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
4103    let mut result = IndentSize::spaces(0);
4104    for c in text {
4105        let kind = match c {
4106            ' ' => IndentKind::Space,
4107            '\t' => IndentKind::Tab,
4108            _ => break,
4109        };
4110        if result.len == 0 {
4111            result.kind = kind;
4112        }
4113        result.len += 1;
4114    }
4115    result
4116}
4117
4118impl Clone for BufferSnapshot {
4119    fn clone(&self) -> Self {
4120        Self {
4121            text: self.text.clone(),
4122            syntax: self.syntax.clone(),
4123            file: self.file.clone(),
4124            remote_selections: self.remote_selections.clone(),
4125            diagnostics: self.diagnostics.clone(),
4126            language: self.language.clone(),
4127            non_text_state_update_count: self.non_text_state_update_count,
4128        }
4129    }
4130}
4131
4132impl Deref for BufferSnapshot {
4133    type Target = text::BufferSnapshot;
4134
4135    fn deref(&self) -> &Self::Target {
4136        &self.text
4137    }
4138}
4139
4140unsafe impl Send for BufferChunks<'_> {}
4141
4142impl<'a> BufferChunks<'a> {
4143    pub(crate) fn new(
4144        text: &'a Rope,
4145        range: Range<usize>,
4146        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
4147        diagnostics: bool,
4148        buffer_snapshot: Option<&'a BufferSnapshot>,
4149    ) -> Self {
4150        let mut highlights = None;
4151        if let Some((captures, highlight_maps)) = syntax {
4152            highlights = Some(BufferChunkHighlights {
4153                captures,
4154                next_capture: None,
4155                stack: Default::default(),
4156                highlight_maps,
4157            })
4158        }
4159
4160        let diagnostic_endpoints = diagnostics.then(|| Vec::new().into_iter().peekable());
4161        let chunks = text.chunks_in_range(range.clone());
4162
4163        let mut this = BufferChunks {
4164            range,
4165            buffer_snapshot,
4166            chunks,
4167            diagnostic_endpoints,
4168            error_depth: 0,
4169            warning_depth: 0,
4170            information_depth: 0,
4171            hint_depth: 0,
4172            unnecessary_depth: 0,
4173            highlights,
4174        };
4175        this.initialize_diagnostic_endpoints();
4176        this
4177    }
4178
4179    /// Seeks to the given byte offset in the buffer.
4180    pub fn seek(&mut self, range: Range<usize>) {
4181        let old_range = std::mem::replace(&mut self.range, range.clone());
4182        self.chunks.set_range(self.range.clone());
4183        if let Some(highlights) = self.highlights.as_mut() {
4184            if old_range.start <= self.range.start && old_range.end >= self.range.end {
4185                // Reuse existing highlights stack, as the new range is a subrange of the old one.
4186                highlights
4187                    .stack
4188                    .retain(|(end_offset, _)| *end_offset > range.start);
4189                if let Some(capture) = &highlights.next_capture {
4190                    if range.start >= capture.node.start_byte() {
4191                        let next_capture_end = capture.node.end_byte();
4192                        if range.start < next_capture_end {
4193                            highlights.stack.push((
4194                                next_capture_end,
4195                                highlights.highlight_maps[capture.grammar_index].get(capture.index),
4196                            ));
4197                        }
4198                        highlights.next_capture.take();
4199                    }
4200                }
4201            } else if let Some(snapshot) = self.buffer_snapshot {
4202                let (captures, highlight_maps) = snapshot.get_highlights(self.range.clone());
4203                *highlights = BufferChunkHighlights {
4204                    captures,
4205                    next_capture: None,
4206                    stack: Default::default(),
4207                    highlight_maps,
4208                };
4209            } else {
4210                // We cannot obtain new highlights for a language-aware buffer iterator, as we don't have a buffer snapshot.
4211                // Seeking such BufferChunks is not supported.
4212                debug_assert!(false, "Attempted to seek on a language-aware buffer iterator without associated buffer snapshot");
4213            }
4214
4215            highlights.captures.set_byte_range(self.range.clone());
4216            self.initialize_diagnostic_endpoints();
4217        }
4218    }
4219
4220    fn initialize_diagnostic_endpoints(&mut self) {
4221        if let Some(diagnostics) = self.diagnostic_endpoints.as_mut() {
4222            if let Some(buffer) = self.buffer_snapshot {
4223                let mut diagnostic_endpoints = Vec::new();
4224                for entry in buffer.diagnostics_in_range::<_, usize>(self.range.clone(), false) {
4225                    diagnostic_endpoints.push(DiagnosticEndpoint {
4226                        offset: entry.range.start,
4227                        is_start: true,
4228                        severity: entry.diagnostic.severity,
4229                        is_unnecessary: entry.diagnostic.is_unnecessary,
4230                    });
4231                    diagnostic_endpoints.push(DiagnosticEndpoint {
4232                        offset: entry.range.end,
4233                        is_start: false,
4234                        severity: entry.diagnostic.severity,
4235                        is_unnecessary: entry.diagnostic.is_unnecessary,
4236                    });
4237                }
4238                diagnostic_endpoints
4239                    .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
4240                *diagnostics = diagnostic_endpoints.into_iter().peekable();
4241                self.hint_depth = 0;
4242                self.error_depth = 0;
4243                self.warning_depth = 0;
4244                self.information_depth = 0;
4245            }
4246        }
4247    }
4248
4249    /// The current byte offset in the buffer.
4250    pub fn offset(&self) -> usize {
4251        self.range.start
4252    }
4253
4254    pub fn range(&self) -> Range<usize> {
4255        self.range.clone()
4256    }
4257
4258    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
4259        let depth = match endpoint.severity {
4260            DiagnosticSeverity::ERROR => &mut self.error_depth,
4261            DiagnosticSeverity::WARNING => &mut self.warning_depth,
4262            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
4263            DiagnosticSeverity::HINT => &mut self.hint_depth,
4264            _ => return,
4265        };
4266        if endpoint.is_start {
4267            *depth += 1;
4268        } else {
4269            *depth -= 1;
4270        }
4271
4272        if endpoint.is_unnecessary {
4273            if endpoint.is_start {
4274                self.unnecessary_depth += 1;
4275            } else {
4276                self.unnecessary_depth -= 1;
4277            }
4278        }
4279    }
4280
4281    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
4282        if self.error_depth > 0 {
4283            Some(DiagnosticSeverity::ERROR)
4284        } else if self.warning_depth > 0 {
4285            Some(DiagnosticSeverity::WARNING)
4286        } else if self.information_depth > 0 {
4287            Some(DiagnosticSeverity::INFORMATION)
4288        } else if self.hint_depth > 0 {
4289            Some(DiagnosticSeverity::HINT)
4290        } else {
4291            None
4292        }
4293    }
4294
4295    fn current_code_is_unnecessary(&self) -> bool {
4296        self.unnecessary_depth > 0
4297    }
4298}
4299
4300impl<'a> Iterator for BufferChunks<'a> {
4301    type Item = Chunk<'a>;
4302
4303    fn next(&mut self) -> Option<Self::Item> {
4304        let mut next_capture_start = usize::MAX;
4305        let mut next_diagnostic_endpoint = usize::MAX;
4306
4307        if let Some(highlights) = self.highlights.as_mut() {
4308            while let Some((parent_capture_end, _)) = highlights.stack.last() {
4309                if *parent_capture_end <= self.range.start {
4310                    highlights.stack.pop();
4311                } else {
4312                    break;
4313                }
4314            }
4315
4316            if highlights.next_capture.is_none() {
4317                highlights.next_capture = highlights.captures.next();
4318            }
4319
4320            while let Some(capture) = highlights.next_capture.as_ref() {
4321                if self.range.start < capture.node.start_byte() {
4322                    next_capture_start = capture.node.start_byte();
4323                    break;
4324                } else {
4325                    let highlight_id =
4326                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
4327                    highlights
4328                        .stack
4329                        .push((capture.node.end_byte(), highlight_id));
4330                    highlights.next_capture = highlights.captures.next();
4331                }
4332            }
4333        }
4334
4335        let mut diagnostic_endpoints = std::mem::take(&mut self.diagnostic_endpoints);
4336        if let Some(diagnostic_endpoints) = diagnostic_endpoints.as_mut() {
4337            while let Some(endpoint) = diagnostic_endpoints.peek().copied() {
4338                if endpoint.offset <= self.range.start {
4339                    self.update_diagnostic_depths(endpoint);
4340                    diagnostic_endpoints.next();
4341                } else {
4342                    next_diagnostic_endpoint = endpoint.offset;
4343                    break;
4344                }
4345            }
4346        }
4347        self.diagnostic_endpoints = diagnostic_endpoints;
4348
4349        if let Some(chunk) = self.chunks.peek() {
4350            let chunk_start = self.range.start;
4351            let mut chunk_end = (self.chunks.offset() + chunk.len())
4352                .min(next_capture_start)
4353                .min(next_diagnostic_endpoint);
4354            let mut highlight_id = None;
4355            if let Some(highlights) = self.highlights.as_ref() {
4356                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
4357                    chunk_end = chunk_end.min(*parent_capture_end);
4358                    highlight_id = Some(*parent_highlight_id);
4359                }
4360            }
4361
4362            let slice =
4363                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
4364            self.range.start = chunk_end;
4365            if self.range.start == self.chunks.offset() + chunk.len() {
4366                self.chunks.next().unwrap();
4367            }
4368
4369            Some(Chunk {
4370                text: slice,
4371                syntax_highlight_id: highlight_id,
4372                diagnostic_severity: self.current_diagnostic_severity(),
4373                is_unnecessary: self.current_code_is_unnecessary(),
4374                ..Default::default()
4375            })
4376        } else {
4377            None
4378        }
4379    }
4380}
4381
4382impl operation_queue::Operation for Operation {
4383    fn lamport_timestamp(&self) -> clock::Lamport {
4384        match self {
4385            Operation::Buffer(_) => {
4386                unreachable!("buffer operations should never be deferred at this layer")
4387            }
4388            Operation::UpdateDiagnostics {
4389                lamport_timestamp, ..
4390            }
4391            | Operation::UpdateSelections {
4392                lamport_timestamp, ..
4393            }
4394            | Operation::UpdateCompletionTriggers {
4395                lamport_timestamp, ..
4396            } => *lamport_timestamp,
4397        }
4398    }
4399}
4400
4401impl Default for Diagnostic {
4402    fn default() -> Self {
4403        Self {
4404            source: Default::default(),
4405            code: None,
4406            severity: DiagnosticSeverity::ERROR,
4407            message: Default::default(),
4408            group_id: 0,
4409            is_primary: false,
4410            is_disk_based: false,
4411            is_unnecessary: false,
4412            data: None,
4413        }
4414    }
4415}
4416
4417impl IndentSize {
4418    /// Returns an [`IndentSize`] representing the given spaces.
4419    pub fn spaces(len: u32) -> Self {
4420        Self {
4421            len,
4422            kind: IndentKind::Space,
4423        }
4424    }
4425
4426    /// Returns an [`IndentSize`] representing a tab.
4427    pub fn tab() -> Self {
4428        Self {
4429            len: 1,
4430            kind: IndentKind::Tab,
4431        }
4432    }
4433
4434    /// An iterator over the characters represented by this [`IndentSize`].
4435    pub fn chars(&self) -> impl Iterator<Item = char> {
4436        iter::repeat(self.char()).take(self.len as usize)
4437    }
4438
4439    /// The character representation of this [`IndentSize`].
4440    pub fn char(&self) -> char {
4441        match self.kind {
4442            IndentKind::Space => ' ',
4443            IndentKind::Tab => '\t',
4444        }
4445    }
4446
4447    /// Consumes the current [`IndentSize`] and returns a new one that has
4448    /// been shrunk or enlarged by the given size along the given direction.
4449    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
4450        match direction {
4451            Ordering::Less => {
4452                if self.kind == size.kind && self.len >= size.len {
4453                    self.len -= size.len;
4454                }
4455            }
4456            Ordering::Equal => {}
4457            Ordering::Greater => {
4458                if self.len == 0 {
4459                    self = size;
4460                } else if self.kind == size.kind {
4461                    self.len += size.len;
4462                }
4463            }
4464        }
4465        self
4466    }
4467
4468    pub fn len_with_expanded_tabs(&self, tab_size: NonZeroU32) -> usize {
4469        match self.kind {
4470            IndentKind::Space => self.len as usize,
4471            IndentKind::Tab => self.len as usize * tab_size.get() as usize,
4472        }
4473    }
4474}
4475
4476#[cfg(any(test, feature = "test-support"))]
4477pub struct TestFile {
4478    pub path: Arc<Path>,
4479    pub root_name: String,
4480    pub local_root: Option<PathBuf>,
4481}
4482
4483#[cfg(any(test, feature = "test-support"))]
4484impl File for TestFile {
4485    fn path(&self) -> &Arc<Path> {
4486        &self.path
4487    }
4488
4489    fn full_path(&self, _: &gpui::App) -> PathBuf {
4490        PathBuf::from(&self.root_name).join(self.path.as_ref())
4491    }
4492
4493    fn as_local(&self) -> Option<&dyn LocalFile> {
4494        if self.local_root.is_some() {
4495            Some(self)
4496        } else {
4497            None
4498        }
4499    }
4500
4501    fn disk_state(&self) -> DiskState {
4502        unimplemented!()
4503    }
4504
4505    fn file_name<'a>(&'a self, _: &'a gpui::App) -> &'a std::ffi::OsStr {
4506        self.path().file_name().unwrap_or(self.root_name.as_ref())
4507    }
4508
4509    fn worktree_id(&self, _: &App) -> WorktreeId {
4510        WorktreeId::from_usize(0)
4511    }
4512
4513    fn as_any(&self) -> &dyn std::any::Any {
4514        unimplemented!()
4515    }
4516
4517    fn to_proto(&self, _: &App) -> rpc::proto::File {
4518        unimplemented!()
4519    }
4520
4521    fn is_private(&self) -> bool {
4522        false
4523    }
4524}
4525
4526#[cfg(any(test, feature = "test-support"))]
4527impl LocalFile for TestFile {
4528    fn abs_path(&self, _cx: &App) -> PathBuf {
4529        PathBuf::from(self.local_root.as_ref().unwrap())
4530            .join(&self.root_name)
4531            .join(self.path.as_ref())
4532    }
4533
4534    fn load(&self, _cx: &App) -> Task<Result<String>> {
4535        unimplemented!()
4536    }
4537
4538    fn load_bytes(&self, _cx: &App) -> Task<Result<Vec<u8>>> {
4539        unimplemented!()
4540    }
4541}
4542
4543pub(crate) fn contiguous_ranges(
4544    values: impl Iterator<Item = u32>,
4545    max_len: usize,
4546) -> impl Iterator<Item = Range<u32>> {
4547    let mut values = values;
4548    let mut current_range: Option<Range<u32>> = None;
4549    std::iter::from_fn(move || loop {
4550        if let Some(value) = values.next() {
4551            if let Some(range) = &mut current_range {
4552                if value == range.end && range.len() < max_len {
4553                    range.end += 1;
4554                    continue;
4555                }
4556            }
4557
4558            let prev_range = current_range.clone();
4559            current_range = Some(value..(value + 1));
4560            if prev_range.is_some() {
4561                return prev_range;
4562            }
4563        } else {
4564            return current_range.take();
4565        }
4566    })
4567}
4568
4569#[derive(Default, Debug)]
4570pub struct CharClassifier {
4571    scope: Option<LanguageScope>,
4572    for_completion: bool,
4573    ignore_punctuation: bool,
4574}
4575
4576impl CharClassifier {
4577    pub fn new(scope: Option<LanguageScope>) -> Self {
4578        Self {
4579            scope,
4580            for_completion: false,
4581            ignore_punctuation: false,
4582        }
4583    }
4584
4585    pub fn for_completion(self, for_completion: bool) -> Self {
4586        Self {
4587            for_completion,
4588            ..self
4589        }
4590    }
4591
4592    pub fn ignore_punctuation(self, ignore_punctuation: bool) -> Self {
4593        Self {
4594            ignore_punctuation,
4595            ..self
4596        }
4597    }
4598
4599    pub fn is_whitespace(&self, c: char) -> bool {
4600        self.kind(c) == CharKind::Whitespace
4601    }
4602
4603    pub fn is_word(&self, c: char) -> bool {
4604        self.kind(c) == CharKind::Word
4605    }
4606
4607    pub fn is_punctuation(&self, c: char) -> bool {
4608        self.kind(c) == CharKind::Punctuation
4609    }
4610
4611    pub fn kind_with(&self, c: char, ignore_punctuation: bool) -> CharKind {
4612        if c.is_whitespace() {
4613            return CharKind::Whitespace;
4614        } else if c.is_alphanumeric() || c == '_' {
4615            return CharKind::Word;
4616        }
4617
4618        if let Some(scope) = &self.scope {
4619            if let Some(characters) = scope.word_characters() {
4620                if characters.contains(&c) {
4621                    if c == '-' && !self.for_completion && !ignore_punctuation {
4622                        return CharKind::Punctuation;
4623                    }
4624                    return CharKind::Word;
4625                }
4626            }
4627        }
4628
4629        if ignore_punctuation {
4630            CharKind::Word
4631        } else {
4632            CharKind::Punctuation
4633        }
4634    }
4635
4636    pub fn kind(&self, c: char) -> CharKind {
4637        self.kind_with(c, self.ignore_punctuation)
4638    }
4639}
4640
4641/// Find all of the ranges of whitespace that occur at the ends of lines
4642/// in the given rope.
4643///
4644/// This could also be done with a regex search, but this implementation
4645/// avoids copying text.
4646pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
4647    let mut ranges = Vec::new();
4648
4649    let mut offset = 0;
4650    let mut prev_chunk_trailing_whitespace_range = 0..0;
4651    for chunk in rope.chunks() {
4652        let mut prev_line_trailing_whitespace_range = 0..0;
4653        for (i, line) in chunk.split('\n').enumerate() {
4654            let line_end_offset = offset + line.len();
4655            let trimmed_line_len = line.trim_end_matches([' ', '\t']).len();
4656            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
4657
4658            if i == 0 && trimmed_line_len == 0 {
4659                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
4660            }
4661            if !prev_line_trailing_whitespace_range.is_empty() {
4662                ranges.push(prev_line_trailing_whitespace_range);
4663            }
4664
4665            offset = line_end_offset + 1;
4666            prev_line_trailing_whitespace_range = trailing_whitespace_range;
4667        }
4668
4669        offset -= 1;
4670        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
4671    }
4672
4673    if !prev_chunk_trailing_whitespace_range.is_empty() {
4674        ranges.push(prev_chunk_trailing_whitespace_range);
4675    }
4676
4677    ranges
4678}