buffer.rs

   1use crate::{
   2    DebuggerTextObject, LanguageScope, Outline, OutlineConfig, RunnableCapture, RunnableTag,
   3    TextObject, TreeSitterOptions,
   4    diagnostic_set::{DiagnosticEntry, DiagnosticEntryRef, DiagnosticGroup},
   5    language_settings::{LanguageSettings, language_settings},
   6    outline::OutlineItem,
   7    syntax_map::{
   8        SyntaxLayer, SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxMapMatch,
   9        SyntaxMapMatches, SyntaxSnapshot, ToTreeSitterPoint,
  10    },
  11    task_context::RunnableRange,
  12    text_diff::text_diff,
  13};
  14pub use crate::{
  15    Grammar, Language, LanguageRegistry,
  16    diagnostic_set::DiagnosticSet,
  17    highlight_map::{HighlightId, HighlightMap},
  18    proto,
  19};
  20use anyhow::{Context as _, Result};
  21use clock::Lamport;
  22pub use clock::ReplicaId;
  23use collections::HashMap;
  24use fs::MTime;
  25use futures::channel::oneshot;
  26use gpui::{
  27    App, AppContext as _, Context, Entity, EventEmitter, HighlightStyle, SharedString, StyledText,
  28    Task, TaskLabel, TextStyle,
  29};
  30
  31use lsp::{LanguageServerId, NumberOrString};
  32use parking_lot::Mutex;
  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    future::Future,
  45    iter::{self, Iterator, Peekable},
  46    mem,
  47    num::NonZeroU32,
  48    ops::{Deref, Range},
  49    path::PathBuf,
  50    rc,
  51    sync::{Arc, LazyLock},
  52    time::{Duration, Instant},
  53    vec,
  54};
  55use sum_tree::TreeMap;
  56use text::operation_queue::OperationQueue;
  57use text::*;
  58pub use text::{
  59    Anchor, Bias, Buffer as TextBuffer, BufferId, BufferSnapshot as TextBufferSnapshot, Edit,
  60    LineIndent, OffsetRangeExt, OffsetUtf16, Patch, Point, PointUtf16, Rope, Selection,
  61    SelectionGoal, Subscription, TextDimension, TextSummary, ToOffset, ToOffsetUtf16, ToPoint,
  62    ToPointUtf16, Transaction, TransactionId, Unclipped,
  63};
  64use theme::{ActiveTheme as _, SyntaxTheme};
  65#[cfg(any(test, feature = "test-support"))]
  66use util::RandomCharIter;
  67use util::{RangeExt, debug_panic, maybe, paths::PathStyle, rel_path::RelPath};
  68
  69#[cfg(any(test, feature = "test-support"))]
  70pub use {tree_sitter_python, tree_sitter_rust, tree_sitter_typescript};
  71
  72pub use lsp::DiagnosticSeverity;
  73
  74/// A label for the background task spawned by the buffer to compute
  75/// a diff against the contents of its file.
  76pub static BUFFER_DIFF_TASK: LazyLock<TaskLabel> = LazyLock::new(TaskLabel::new);
  77
  78/// Indicate whether a [`Buffer`] has permissions to edit.
  79#[derive(PartialEq, Clone, Copy, Debug)]
  80pub enum Capability {
  81    /// The buffer is a mutable replica.
  82    ReadWrite,
  83    /// The buffer is a read-only replica.
  84    ReadOnly,
  85}
  86
  87pub type BufferRow = u32;
  88
  89/// An in-memory representation of a source code file, including its text,
  90/// syntax trees, git status, and diagnostics.
  91pub struct Buffer {
  92    text: TextBuffer,
  93    branch_state: Option<BufferBranchState>,
  94    /// Filesystem state, `None` when there is no path.
  95    file: Option<Arc<dyn File>>,
  96    /// The mtime of the file when this buffer was last loaded from
  97    /// or saved to disk.
  98    saved_mtime: Option<MTime>,
  99    /// The version vector when this buffer was last loaded from
 100    /// or saved to disk.
 101    saved_version: clock::Global,
 102    preview_version: clock::Global,
 103    transaction_depth: usize,
 104    was_dirty_before_starting_transaction: Option<bool>,
 105    reload_task: Option<Task<Result<()>>>,
 106    language: Option<Arc<Language>>,
 107    autoindent_requests: Vec<Arc<AutoindentRequest>>,
 108    wait_for_autoindent_txs: Vec<oneshot::Sender<()>>,
 109    pending_autoindent: Option<Task<()>>,
 110    sync_parse_timeout: Duration,
 111    syntax_map: Mutex<SyntaxMap>,
 112    reparse: Option<Task<()>>,
 113    parse_status: (watch::Sender<ParseStatus>, watch::Receiver<ParseStatus>),
 114    non_text_state_update_count: usize,
 115    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 116    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 117    diagnostics_timestamp: clock::Lamport,
 118    completion_triggers: BTreeSet<String>,
 119    completion_triggers_per_language_server: HashMap<LanguageServerId, BTreeSet<String>>,
 120    completion_triggers_timestamp: clock::Lamport,
 121    deferred_ops: OperationQueue<Operation>,
 122    capability: Capability,
 123    has_conflict: bool,
 124    /// Memoize calls to has_changes_since(saved_version).
 125    /// The contents of a cell are (self.version, has_changes) at the time of a last call.
 126    has_unsaved_edits: Cell<(clock::Global, bool)>,
 127    change_bits: Vec<rc::Weak<Cell<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 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, PartialEq, Eq)]
 176pub enum CursorShape {
 177    /// A vertical bar
 178    #[default]
 179    Bar,
 180    /// A block that surrounds the following character
 181    Block,
 182    /// An underline that runs along the following character
 183    Underline,
 184    /// A box drawn around the following character
 185    Hollow,
 186}
 187
 188impl From<settings::CursorShape> for CursorShape {
 189    fn from(shape: settings::CursorShape) -> Self {
 190        match shape {
 191            settings::CursorShape::Bar => CursorShape::Bar,
 192            settings::CursorShape::Block => CursorShape::Block,
 193            settings::CursorShape::Underline => CursorShape::Underline,
 194            settings::CursorShape::Hollow => CursorShape::Hollow,
 195        }
 196    }
 197}
 198
 199#[derive(Clone, Debug)]
 200struct SelectionSet {
 201    line_mode: bool,
 202    cursor_shape: CursorShape,
 203    selections: Arc<[Selection<Anchor>]>,
 204    lamport_timestamp: clock::Lamport,
 205}
 206
 207/// A diagnostic associated with a certain range of a buffer.
 208#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 209pub struct Diagnostic {
 210    /// The name of the service that produced this diagnostic.
 211    pub source: Option<String>,
 212    /// A machine-readable code that identifies this diagnostic.
 213    pub code: Option<NumberOrString>,
 214    pub code_description: Option<lsp::Uri>,
 215    /// Whether this diagnostic is a hint, warning, or error.
 216    pub severity: DiagnosticSeverity,
 217    /// The human-readable message associated with this diagnostic.
 218    pub message: String,
 219    /// The human-readable message (in markdown format)
 220    pub markdown: Option<String>,
 221    /// An id that identifies the group to which this diagnostic belongs.
 222    ///
 223    /// When a language server produces a diagnostic with
 224    /// one or more associated diagnostics, those diagnostics are all
 225    /// assigned a single group ID.
 226    pub group_id: usize,
 227    /// Whether this diagnostic is the primary diagnostic for its group.
 228    ///
 229    /// In a given group, the primary diagnostic is the top-level diagnostic
 230    /// returned by the language server. The non-primary diagnostics are the
 231    /// associated diagnostics.
 232    pub is_primary: bool,
 233    /// Whether this diagnostic is considered to originate from an analysis of
 234    /// files on disk, as opposed to any unsaved buffer contents. This is a
 235    /// property of a given diagnostic source, and is configured for a given
 236    /// language server via the [`LspAdapter::disk_based_diagnostic_sources`](crate::LspAdapter::disk_based_diagnostic_sources) method
 237    /// for the language server.
 238    pub is_disk_based: bool,
 239    /// Whether this diagnostic marks unnecessary code.
 240    pub is_unnecessary: bool,
 241    /// Quick separation of diagnostics groups based by their source.
 242    pub source_kind: DiagnosticSourceKind,
 243    /// Data from language server that produced this diagnostic. Passed back to the LS when we request code actions for this diagnostic.
 244    pub data: Option<Value>,
 245    /// Whether to underline the corresponding text range in the editor.
 246    pub underline: bool,
 247}
 248
 249#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
 250pub enum DiagnosticSourceKind {
 251    Pulled,
 252    Pushed,
 253    Other,
 254}
 255
 256/// An operation used to synchronize this buffer with its other replicas.
 257#[derive(Clone, Debug, PartialEq)]
 258pub enum Operation {
 259    /// A text operation.
 260    Buffer(text::Operation),
 261
 262    /// An update to the buffer's diagnostics.
 263    UpdateDiagnostics {
 264        /// The id of the language server that produced the new diagnostics.
 265        server_id: LanguageServerId,
 266        /// The diagnostics.
 267        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 268        /// The buffer's lamport timestamp.
 269        lamport_timestamp: clock::Lamport,
 270    },
 271
 272    /// An update to the most recent selections in this buffer.
 273    UpdateSelections {
 274        /// The selections.
 275        selections: Arc<[Selection<Anchor>]>,
 276        /// The buffer's lamport timestamp.
 277        lamport_timestamp: clock::Lamport,
 278        /// Whether the selections are in 'line mode'.
 279        line_mode: bool,
 280        /// The [`CursorShape`] associated with these selections.
 281        cursor_shape: CursorShape,
 282    },
 283
 284    /// An update to the characters that should trigger autocompletion
 285    /// for this buffer.
 286    UpdateCompletionTriggers {
 287        /// The characters that trigger autocompletion.
 288        triggers: Vec<String>,
 289        /// The buffer's lamport timestamp.
 290        lamport_timestamp: clock::Lamport,
 291        /// The language server ID.
 292        server_id: LanguageServerId,
 293    },
 294
 295    /// An update to the line ending type of this buffer.
 296    UpdateLineEnding {
 297        /// The line ending type.
 298        line_ending: LineEnding,
 299        /// The buffer's lamport timestamp.
 300        lamport_timestamp: clock::Lamport,
 301    },
 302}
 303
 304/// An event that occurs in a buffer.
 305#[derive(Clone, Debug, PartialEq)]
 306pub enum BufferEvent {
 307    /// The buffer was changed in a way that must be
 308    /// propagated to its other replicas.
 309    Operation {
 310        operation: Operation,
 311        is_local: bool,
 312    },
 313    /// The buffer was edited.
 314    Edited,
 315    /// The buffer's `dirty` bit changed.
 316    DirtyChanged,
 317    /// The buffer was saved.
 318    Saved,
 319    /// The buffer's file was changed on disk.
 320    FileHandleChanged,
 321    /// The buffer was reloaded.
 322    Reloaded,
 323    /// The buffer is in need of a reload
 324    ReloadNeeded,
 325    /// The buffer's language was changed.
 326    LanguageChanged,
 327    /// The buffer's syntax trees were updated.
 328    Reparsed,
 329    /// The buffer's diagnostics were updated.
 330    DiagnosticsUpdated,
 331    /// The buffer gained or lost editing capabilities.
 332    CapabilityChanged,
 333}
 334
 335/// The file associated with a buffer.
 336pub trait File: Send + Sync + Any {
 337    /// Returns the [`LocalFile`] associated with this file, if the
 338    /// file is local.
 339    fn as_local(&self) -> Option<&dyn LocalFile>;
 340
 341    /// Returns whether this file is local.
 342    fn is_local(&self) -> bool {
 343        self.as_local().is_some()
 344    }
 345
 346    /// Returns whether the file is new, exists in storage, or has been deleted. Includes metadata
 347    /// only available in some states, such as modification time.
 348    fn disk_state(&self) -> DiskState;
 349
 350    /// Returns the path of this file relative to the worktree's root directory.
 351    fn path(&self) -> &Arc<RelPath>;
 352
 353    /// Returns the path of this file relative to the worktree's parent directory (this means it
 354    /// includes the name of the worktree's root folder).
 355    fn full_path(&self, cx: &App) -> PathBuf;
 356
 357    /// Returns the path style of this file.
 358    fn path_style(&self, cx: &App) -> PathStyle;
 359
 360    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 361    /// of its worktree, then this method will return the name of the worktree itself.
 362    fn file_name<'a>(&'a self, cx: &'a App) -> &'a str;
 363
 364    /// Returns the id of the worktree to which this file belongs.
 365    ///
 366    /// This is needed for looking up project-specific settings.
 367    fn worktree_id(&self, cx: &App) -> WorktreeId;
 368
 369    /// Converts this file into a protobuf message.
 370    fn to_proto(&self, cx: &App) -> rpc::proto::File;
 371
 372    /// Return whether Zed considers this to be a private file.
 373    fn is_private(&self) -> bool;
 374}
 375
 376/// The file's storage status - whether it's stored (`Present`), and if so when it was last
 377/// modified. In the case where the file is not stored, it can be either `New` or `Deleted`. In the
 378/// UI these two states are distinguished. For example, the buffer tab does not display a deletion
 379/// indicator for new files.
 380#[derive(Copy, Clone, Debug, PartialEq)]
 381pub enum DiskState {
 382    /// File created in Zed that has not been saved.
 383    New,
 384    /// File present on the filesystem.
 385    Present { mtime: MTime },
 386    /// Deleted file that was previously present.
 387    Deleted,
 388}
 389
 390impl DiskState {
 391    /// Returns the file's last known modification time on disk.
 392    pub fn mtime(self) -> Option<MTime> {
 393        match self {
 394            DiskState::New => None,
 395            DiskState::Present { mtime } => Some(mtime),
 396            DiskState::Deleted => None,
 397        }
 398    }
 399
 400    pub fn exists(&self) -> bool {
 401        match self {
 402            DiskState::New => false,
 403            DiskState::Present { .. } => true,
 404            DiskState::Deleted => false,
 405        }
 406    }
 407}
 408
 409/// The file associated with a buffer, in the case where the file is on the local disk.
 410pub trait LocalFile: File {
 411    /// Returns the absolute path of this file
 412    fn abs_path(&self, cx: &App) -> PathBuf;
 413
 414    /// Loads the file contents from disk and returns them as a UTF-8 encoded string.
 415    fn load(&self, cx: &App) -> Task<Result<String>>;
 416
 417    /// Loads the file's contents from disk.
 418    fn load_bytes(&self, cx: &App) -> Task<Result<Vec<u8>>>;
 419}
 420
 421/// The auto-indent behavior associated with an editing operation.
 422/// For some editing operations, each affected line of text has its
 423/// indentation recomputed. For other operations, the entire block
 424/// of edited text is adjusted uniformly.
 425#[derive(Clone, Debug)]
 426pub enum AutoindentMode {
 427    /// Indent each line of inserted text.
 428    EachLine,
 429    /// Apply the same indentation adjustment to all of the lines
 430    /// in a given insertion.
 431    Block {
 432        /// The original indentation column of the first line of each
 433        /// insertion, if it has been copied.
 434        ///
 435        /// Knowing this makes it possible to preserve the relative indentation
 436        /// of every line in the insertion from when it was copied.
 437        ///
 438        /// If the original indent column is `a`, and the first line of insertion
 439        /// is then auto-indented to column `b`, then every other line of
 440        /// the insertion will be auto-indented to column `b - a`
 441        original_indent_columns: Vec<Option<u32>>,
 442    },
 443}
 444
 445#[derive(Clone)]
 446struct AutoindentRequest {
 447    before_edit: BufferSnapshot,
 448    entries: Vec<AutoindentRequestEntry>,
 449    is_block_mode: bool,
 450    ignore_empty_lines: bool,
 451}
 452
 453#[derive(Debug, Clone)]
 454struct AutoindentRequestEntry {
 455    /// A range of the buffer whose indentation should be adjusted.
 456    range: Range<Anchor>,
 457    /// Whether or not these lines should be considered brand new, for the
 458    /// purpose of auto-indent. When text is not new, its indentation will
 459    /// only be adjusted if the suggested indentation level has *changed*
 460    /// since the edit was made.
 461    first_line_is_new: bool,
 462    indent_size: IndentSize,
 463    original_indent_column: Option<u32>,
 464}
 465
 466#[derive(Debug)]
 467struct IndentSuggestion {
 468    basis_row: u32,
 469    delta: Ordering,
 470    within_error: bool,
 471}
 472
 473struct BufferChunkHighlights<'a> {
 474    captures: SyntaxMapCaptures<'a>,
 475    next_capture: Option<SyntaxMapCapture<'a>>,
 476    stack: Vec<(usize, HighlightId)>,
 477    highlight_maps: Vec<HighlightMap>,
 478}
 479
 480/// An iterator that yields chunks of a buffer's text, along with their
 481/// syntax highlights and diagnostic status.
 482pub struct BufferChunks<'a> {
 483    buffer_snapshot: Option<&'a BufferSnapshot>,
 484    range: Range<usize>,
 485    chunks: text::Chunks<'a>,
 486    diagnostic_endpoints: Option<Peekable<vec::IntoIter<DiagnosticEndpoint>>>,
 487    error_depth: usize,
 488    warning_depth: usize,
 489    information_depth: usize,
 490    hint_depth: usize,
 491    unnecessary_depth: usize,
 492    underline: bool,
 493    highlights: Option<BufferChunkHighlights<'a>>,
 494}
 495
 496/// A chunk of a buffer's text, along with its syntax highlight and
 497/// diagnostic status.
 498#[derive(Clone, Debug, Default)]
 499pub struct Chunk<'a> {
 500    /// The text of the chunk.
 501    pub text: &'a str,
 502    /// The syntax highlighting style of the chunk.
 503    pub syntax_highlight_id: Option<HighlightId>,
 504    /// The highlight style that has been applied to this chunk in
 505    /// the editor.
 506    pub highlight_style: Option<HighlightStyle>,
 507    /// The severity of diagnostic associated with this chunk, if any.
 508    pub diagnostic_severity: Option<DiagnosticSeverity>,
 509    /// A bitset of which characters are tabs in this string.
 510    pub tabs: u128,
 511    /// Bitmap of character indices in this chunk
 512    pub chars: u128,
 513    /// Whether this chunk of text is marked as unnecessary.
 514    pub is_unnecessary: bool,
 515    /// Whether this chunk of text was originally a tab character.
 516    pub is_tab: bool,
 517    /// Whether this chunk of text was originally an inlay.
 518    pub is_inlay: bool,
 519    /// Whether to underline the corresponding text range in the editor.
 520    pub underline: bool,
 521}
 522
 523/// A set of edits to a given version of a buffer, computed asynchronously.
 524#[derive(Debug)]
 525pub struct Diff {
 526    pub base_version: clock::Global,
 527    pub line_ending: LineEnding,
 528    pub edits: Vec<(Range<usize>, Arc<str>)>,
 529}
 530
 531#[derive(Debug, Clone, Copy)]
 532pub(crate) struct DiagnosticEndpoint {
 533    offset: usize,
 534    is_start: bool,
 535    underline: bool,
 536    severity: DiagnosticSeverity,
 537    is_unnecessary: bool,
 538}
 539
 540/// A class of characters, used for characterizing a run of text.
 541#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 542pub enum CharKind {
 543    /// Whitespace.
 544    Whitespace,
 545    /// Punctuation.
 546    Punctuation,
 547    /// Word.
 548    Word,
 549}
 550
 551/// Context for character classification within a specific scope.
 552#[derive(Copy, Clone, Eq, PartialEq, Debug)]
 553pub enum CharScopeContext {
 554    /// Character classification for completion queries.
 555    ///
 556    /// This context treats certain characters as word constituents that would
 557    /// normally be considered punctuation, such as '-' in Tailwind classes
 558    /// ("bg-yellow-100") or '.' in import paths ("foo.ts").
 559    Completion,
 560    /// Character classification for linked edits.
 561    ///
 562    /// This context handles characters that should be treated as part of
 563    /// identifiers during linked editing operations, such as '.' in JSX
 564    /// component names like `<Animated.View>`.
 565    LinkedEdit,
 566}
 567
 568/// A runnable is a set of data about a region that could be resolved into a task
 569pub struct Runnable {
 570    pub tags: SmallVec<[RunnableTag; 1]>,
 571    pub language: Arc<Language>,
 572    pub buffer: BufferId,
 573}
 574
 575#[derive(Default, Clone, Debug)]
 576pub struct HighlightedText {
 577    pub text: SharedString,
 578    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 579}
 580
 581#[derive(Default, Debug)]
 582struct HighlightedTextBuilder {
 583    pub text: String,
 584    highlights: Vec<(Range<usize>, HighlightStyle)>,
 585}
 586
 587impl HighlightedText {
 588    pub fn from_buffer_range<T: ToOffset>(
 589        range: Range<T>,
 590        snapshot: &text::BufferSnapshot,
 591        syntax_snapshot: &SyntaxSnapshot,
 592        override_style: Option<HighlightStyle>,
 593        syntax_theme: &SyntaxTheme,
 594    ) -> Self {
 595        let mut highlighted_text = HighlightedTextBuilder::default();
 596        highlighted_text.add_text_from_buffer_range(
 597            range,
 598            snapshot,
 599            syntax_snapshot,
 600            override_style,
 601            syntax_theme,
 602        );
 603        highlighted_text.build()
 604    }
 605
 606    pub fn to_styled_text(&self, default_style: &TextStyle) -> StyledText {
 607        gpui::StyledText::new(self.text.clone())
 608            .with_default_highlights(default_style, self.highlights.iter().cloned())
 609    }
 610
 611    /// Returns the first line without leading whitespace unless highlighted
 612    /// and a boolean indicating if there are more lines after
 613    pub fn first_line_preview(self) -> (Self, bool) {
 614        let newline_ix = self.text.find('\n').unwrap_or(self.text.len());
 615        let first_line = &self.text[..newline_ix];
 616
 617        // Trim leading whitespace, unless an edit starts prior to it.
 618        let mut preview_start_ix = first_line.len() - first_line.trim_start().len();
 619        if let Some((first_highlight_range, _)) = self.highlights.first() {
 620            preview_start_ix = preview_start_ix.min(first_highlight_range.start);
 621        }
 622
 623        let preview_text = &first_line[preview_start_ix..];
 624        let preview_highlights = self
 625            .highlights
 626            .into_iter()
 627            .skip_while(|(range, _)| range.end <= preview_start_ix)
 628            .take_while(|(range, _)| range.start < newline_ix)
 629            .filter_map(|(mut range, highlight)| {
 630                range.start = range.start.saturating_sub(preview_start_ix);
 631                range.end = range.end.min(newline_ix).saturating_sub(preview_start_ix);
 632                if range.is_empty() {
 633                    None
 634                } else {
 635                    Some((range, highlight))
 636                }
 637            });
 638
 639        let preview = Self {
 640            text: SharedString::new(preview_text),
 641            highlights: preview_highlights.collect(),
 642        };
 643
 644        (preview, self.text.len() > newline_ix)
 645    }
 646}
 647
 648impl HighlightedTextBuilder {
 649    pub fn build(self) -> HighlightedText {
 650        HighlightedText {
 651            text: self.text.into(),
 652            highlights: self.highlights,
 653        }
 654    }
 655
 656    pub fn add_text_from_buffer_range<T: ToOffset>(
 657        &mut self,
 658        range: Range<T>,
 659        snapshot: &text::BufferSnapshot,
 660        syntax_snapshot: &SyntaxSnapshot,
 661        override_style: Option<HighlightStyle>,
 662        syntax_theme: &SyntaxTheme,
 663    ) {
 664        let range = range.to_offset(snapshot);
 665        for chunk in Self::highlighted_chunks(range, snapshot, syntax_snapshot) {
 666            let start = self.text.len();
 667            self.text.push_str(chunk.text);
 668            let end = self.text.len();
 669
 670            if let Some(highlight_style) = chunk
 671                .syntax_highlight_id
 672                .and_then(|id| id.style(syntax_theme))
 673            {
 674                let highlight_style = override_style.map_or(highlight_style, |override_style| {
 675                    highlight_style.highlight(override_style)
 676                });
 677                self.highlights.push((start..end, highlight_style));
 678            } else if let Some(override_style) = override_style {
 679                self.highlights.push((start..end, override_style));
 680            }
 681        }
 682    }
 683
 684    fn highlighted_chunks<'a>(
 685        range: Range<usize>,
 686        snapshot: &'a text::BufferSnapshot,
 687        syntax_snapshot: &'a SyntaxSnapshot,
 688    ) -> BufferChunks<'a> {
 689        let captures = syntax_snapshot.captures(range.clone(), snapshot, |grammar| {
 690            grammar
 691                .highlights_config
 692                .as_ref()
 693                .map(|config| &config.query)
 694        });
 695
 696        let highlight_maps = captures
 697            .grammars()
 698            .iter()
 699            .map(|grammar| grammar.highlight_map())
 700            .collect();
 701
 702        BufferChunks::new(
 703            snapshot.as_rope(),
 704            range,
 705            Some((captures, highlight_maps)),
 706            false,
 707            None,
 708        )
 709    }
 710}
 711
 712#[derive(Clone)]
 713pub struct EditPreview {
 714    old_snapshot: text::BufferSnapshot,
 715    applied_edits_snapshot: text::BufferSnapshot,
 716    syntax_snapshot: SyntaxSnapshot,
 717}
 718
 719impl EditPreview {
 720    pub fn highlight_edits(
 721        &self,
 722        current_snapshot: &BufferSnapshot,
 723        edits: &[(Range<Anchor>, String)],
 724        include_deletions: bool,
 725        cx: &App,
 726    ) -> HighlightedText {
 727        let Some(visible_range_in_preview_snapshot) = self.compute_visible_range(edits) else {
 728            return HighlightedText::default();
 729        };
 730
 731        let mut highlighted_text = HighlightedTextBuilder::default();
 732
 733        let mut offset_in_preview_snapshot = visible_range_in_preview_snapshot.start;
 734
 735        let insertion_highlight_style = HighlightStyle {
 736            background_color: Some(cx.theme().status().created_background),
 737            ..Default::default()
 738        };
 739        let deletion_highlight_style = HighlightStyle {
 740            background_color: Some(cx.theme().status().deleted_background),
 741            ..Default::default()
 742        };
 743        let syntax_theme = cx.theme().syntax();
 744
 745        for (range, edit_text) in edits {
 746            let edit_new_end_in_preview_snapshot = range
 747                .end
 748                .bias_right(&self.old_snapshot)
 749                .to_offset(&self.applied_edits_snapshot);
 750            let edit_start_in_preview_snapshot = edit_new_end_in_preview_snapshot - edit_text.len();
 751
 752            let unchanged_range_in_preview_snapshot =
 753                offset_in_preview_snapshot..edit_start_in_preview_snapshot;
 754            if !unchanged_range_in_preview_snapshot.is_empty() {
 755                highlighted_text.add_text_from_buffer_range(
 756                    unchanged_range_in_preview_snapshot,
 757                    &self.applied_edits_snapshot,
 758                    &self.syntax_snapshot,
 759                    None,
 760                    syntax_theme,
 761                );
 762            }
 763
 764            let range_in_current_snapshot = range.to_offset(current_snapshot);
 765            if include_deletions && !range_in_current_snapshot.is_empty() {
 766                highlighted_text.add_text_from_buffer_range(
 767                    range_in_current_snapshot,
 768                    &current_snapshot.text,
 769                    &current_snapshot.syntax,
 770                    Some(deletion_highlight_style),
 771                    syntax_theme,
 772                );
 773            }
 774
 775            if !edit_text.is_empty() {
 776                highlighted_text.add_text_from_buffer_range(
 777                    edit_start_in_preview_snapshot..edit_new_end_in_preview_snapshot,
 778                    &self.applied_edits_snapshot,
 779                    &self.syntax_snapshot,
 780                    Some(insertion_highlight_style),
 781                    syntax_theme,
 782                );
 783            }
 784
 785            offset_in_preview_snapshot = edit_new_end_in_preview_snapshot;
 786        }
 787
 788        highlighted_text.add_text_from_buffer_range(
 789            offset_in_preview_snapshot..visible_range_in_preview_snapshot.end,
 790            &self.applied_edits_snapshot,
 791            &self.syntax_snapshot,
 792            None,
 793            syntax_theme,
 794        );
 795
 796        highlighted_text.build()
 797    }
 798
 799    fn compute_visible_range(&self, edits: &[(Range<Anchor>, String)]) -> Option<Range<usize>> {
 800        let (first, _) = edits.first()?;
 801        let (last, _) = edits.last()?;
 802
 803        let start = first
 804            .start
 805            .bias_left(&self.old_snapshot)
 806            .to_point(&self.applied_edits_snapshot);
 807        let end = last
 808            .end
 809            .bias_right(&self.old_snapshot)
 810            .to_point(&self.applied_edits_snapshot);
 811
 812        // Ensure that the first line of the first edit and the last line of the last edit are always fully visible
 813        let range = Point::new(start.row, 0)
 814            ..Point::new(end.row, self.applied_edits_snapshot.line_len(end.row));
 815
 816        Some(range.to_offset(&self.applied_edits_snapshot))
 817    }
 818}
 819
 820#[derive(Clone, Debug, PartialEq, Eq)]
 821pub struct BracketMatch {
 822    pub open_range: Range<usize>,
 823    pub close_range: Range<usize>,
 824    pub newline_only: bool,
 825}
 826
 827impl Buffer {
 828    /// Create a new buffer with the given base text.
 829    pub fn local<T: Into<String>>(base_text: T, cx: &Context<Self>) -> Self {
 830        Self::build(
 831            TextBuffer::new(
 832                ReplicaId::LOCAL,
 833                cx.entity_id().as_non_zero_u64().into(),
 834                base_text.into(),
 835            ),
 836            None,
 837            Capability::ReadWrite,
 838        )
 839    }
 840
 841    /// Create a new buffer with the given base text that has proper line endings and other normalization applied.
 842    pub fn local_normalized(
 843        base_text_normalized: Rope,
 844        line_ending: LineEnding,
 845        cx: &Context<Self>,
 846    ) -> Self {
 847        Self::build(
 848            TextBuffer::new_normalized(
 849                ReplicaId::LOCAL,
 850                cx.entity_id().as_non_zero_u64().into(),
 851                line_ending,
 852                base_text_normalized,
 853            ),
 854            None,
 855            Capability::ReadWrite,
 856        )
 857    }
 858
 859    /// Create a new buffer that is a replica of a remote buffer.
 860    pub fn remote(
 861        remote_id: BufferId,
 862        replica_id: ReplicaId,
 863        capability: Capability,
 864        base_text: impl Into<String>,
 865    ) -> Self {
 866        Self::build(
 867            TextBuffer::new(replica_id, remote_id, base_text.into()),
 868            None,
 869            capability,
 870        )
 871    }
 872
 873    /// Create a new buffer that is a replica of a remote buffer, populating its
 874    /// state from the given protobuf message.
 875    pub fn from_proto(
 876        replica_id: ReplicaId,
 877        capability: Capability,
 878        message: proto::BufferState,
 879        file: Option<Arc<dyn File>>,
 880    ) -> Result<Self> {
 881        let buffer_id = BufferId::new(message.id).context("Could not deserialize buffer_id")?;
 882        let buffer = TextBuffer::new(replica_id, buffer_id, message.base_text);
 883        let mut this = Self::build(buffer, file, capability);
 884        this.text.set_line_ending(proto::deserialize_line_ending(
 885            rpc::proto::LineEnding::from_i32(message.line_ending).context("missing line_ending")?,
 886        ));
 887        this.saved_version = proto::deserialize_version(&message.saved_version);
 888        this.saved_mtime = message.saved_mtime.map(|time| time.into());
 889        Ok(this)
 890    }
 891
 892    /// Serialize the buffer's state to a protobuf message.
 893    pub fn to_proto(&self, cx: &App) -> proto::BufferState {
 894        proto::BufferState {
 895            id: self.remote_id().into(),
 896            file: self.file.as_ref().map(|f| f.to_proto(cx)),
 897            base_text: self.base_text().to_string(),
 898            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 899            saved_version: proto::serialize_version(&self.saved_version),
 900            saved_mtime: self.saved_mtime.map(|time| time.into()),
 901        }
 902    }
 903
 904    /// Serialize as protobufs all of the changes to the buffer since the given version.
 905    pub fn serialize_ops(
 906        &self,
 907        since: Option<clock::Global>,
 908        cx: &App,
 909    ) -> Task<Vec<proto::Operation>> {
 910        let mut operations = Vec::new();
 911        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 912
 913        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 914            proto::serialize_operation(&Operation::UpdateSelections {
 915                selections: set.selections.clone(),
 916                lamport_timestamp: set.lamport_timestamp,
 917                line_mode: set.line_mode,
 918                cursor_shape: set.cursor_shape,
 919            })
 920        }));
 921
 922        for (server_id, diagnostics) in &self.diagnostics {
 923            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 924                lamport_timestamp: self.diagnostics_timestamp,
 925                server_id: *server_id,
 926                diagnostics: diagnostics.iter().cloned().collect(),
 927            }));
 928        }
 929
 930        for (server_id, completions) in &self.completion_triggers_per_language_server {
 931            operations.push(proto::serialize_operation(
 932                &Operation::UpdateCompletionTriggers {
 933                    triggers: completions.iter().cloned().collect(),
 934                    lamport_timestamp: self.completion_triggers_timestamp,
 935                    server_id: *server_id,
 936                },
 937            ));
 938        }
 939
 940        let text_operations = self.text.operations().clone();
 941        cx.background_spawn(async move {
 942            let since = since.unwrap_or_default();
 943            operations.extend(
 944                text_operations
 945                    .iter()
 946                    .filter(|(_, op)| !since.observed(op.timestamp()))
 947                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 948            );
 949            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 950            operations
 951        })
 952    }
 953
 954    /// Assign a language to the buffer, returning the buffer.
 955    pub fn with_language(mut self, language: Arc<Language>, cx: &mut Context<Self>) -> Self {
 956        self.set_language(Some(language), cx);
 957        self
 958    }
 959
 960    /// Returns the [`Capability`] of this buffer.
 961    pub fn capability(&self) -> Capability {
 962        self.capability
 963    }
 964
 965    /// Whether this buffer can only be read.
 966    pub fn read_only(&self) -> bool {
 967        self.capability == Capability::ReadOnly
 968    }
 969
 970    /// Builds a [`Buffer`] with the given underlying [`TextBuffer`], diff base, [`File`] and [`Capability`].
 971    pub fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>, capability: Capability) -> Self {
 972        let saved_mtime = file.as_ref().and_then(|file| file.disk_state().mtime());
 973        let snapshot = buffer.snapshot();
 974        let syntax_map = Mutex::new(SyntaxMap::new(&snapshot));
 975        Self {
 976            saved_mtime,
 977            saved_version: buffer.version(),
 978            preview_version: buffer.version(),
 979            reload_task: None,
 980            transaction_depth: 0,
 981            was_dirty_before_starting_transaction: None,
 982            has_unsaved_edits: Cell::new((buffer.version(), false)),
 983            text: buffer,
 984            branch_state: None,
 985            file,
 986            capability,
 987            syntax_map,
 988            reparse: None,
 989            non_text_state_update_count: 0,
 990            sync_parse_timeout: Duration::from_millis(1),
 991            parse_status: watch::channel(ParseStatus::Idle),
 992            autoindent_requests: Default::default(),
 993            wait_for_autoindent_txs: Default::default(),
 994            pending_autoindent: Default::default(),
 995            language: None,
 996            remote_selections: Default::default(),
 997            diagnostics: Default::default(),
 998            diagnostics_timestamp: Lamport::MIN,
 999            completion_triggers: Default::default(),
1000            completion_triggers_per_language_server: Default::default(),
1001            completion_triggers_timestamp: Lamport::MIN,
1002            deferred_ops: OperationQueue::new(),
1003            has_conflict: false,
1004            change_bits: Default::default(),
1005            _subscriptions: Vec::new(),
1006        }
1007    }
1008
1009    pub fn build_snapshot(
1010        text: Rope,
1011        language: Option<Arc<Language>>,
1012        language_registry: Option<Arc<LanguageRegistry>>,
1013        cx: &mut App,
1014    ) -> impl Future<Output = BufferSnapshot> + use<> {
1015        let entity_id = cx.reserve_entity::<Self>().entity_id();
1016        let buffer_id = entity_id.as_non_zero_u64().into();
1017        async move {
1018            let text =
1019                TextBuffer::new_normalized(ReplicaId::LOCAL, buffer_id, Default::default(), text)
1020                    .snapshot();
1021            let mut syntax = SyntaxMap::new(&text).snapshot();
1022            if let Some(language) = language.clone() {
1023                let language_registry = language_registry.clone();
1024                syntax.reparse(&text, language_registry, language);
1025            }
1026            BufferSnapshot {
1027                text,
1028                syntax,
1029                file: None,
1030                diagnostics: Default::default(),
1031                remote_selections: Default::default(),
1032                language,
1033                non_text_state_update_count: 0,
1034            }
1035        }
1036    }
1037
1038    pub fn build_empty_snapshot(cx: &mut App) -> BufferSnapshot {
1039        let entity_id = cx.reserve_entity::<Self>().entity_id();
1040        let buffer_id = entity_id.as_non_zero_u64().into();
1041        let text = TextBuffer::new_normalized(
1042            ReplicaId::LOCAL,
1043            buffer_id,
1044            Default::default(),
1045            Rope::new(),
1046        )
1047        .snapshot();
1048        let syntax = SyntaxMap::new(&text).snapshot();
1049        BufferSnapshot {
1050            text,
1051            syntax,
1052            file: None,
1053            diagnostics: Default::default(),
1054            remote_selections: Default::default(),
1055            language: None,
1056            non_text_state_update_count: 0,
1057        }
1058    }
1059
1060    #[cfg(any(test, feature = "test-support"))]
1061    pub fn build_snapshot_sync(
1062        text: Rope,
1063        language: Option<Arc<Language>>,
1064        language_registry: Option<Arc<LanguageRegistry>>,
1065        cx: &mut App,
1066    ) -> BufferSnapshot {
1067        let entity_id = cx.reserve_entity::<Self>().entity_id();
1068        let buffer_id = entity_id.as_non_zero_u64().into();
1069        let text =
1070            TextBuffer::new_normalized(ReplicaId::LOCAL, buffer_id, Default::default(), text)
1071                .snapshot();
1072        let mut syntax = SyntaxMap::new(&text).snapshot();
1073        if let Some(language) = language.clone() {
1074            syntax.reparse(&text, language_registry, language);
1075        }
1076        BufferSnapshot {
1077            text,
1078            syntax,
1079            file: None,
1080            diagnostics: Default::default(),
1081            remote_selections: Default::default(),
1082            language,
1083            non_text_state_update_count: 0,
1084        }
1085    }
1086
1087    /// Retrieve a snapshot of the buffer's current state. This is computationally
1088    /// cheap, and allows reading from the buffer on a background thread.
1089    pub fn snapshot(&self) -> BufferSnapshot {
1090        let text = self.text.snapshot();
1091        let mut syntax_map = self.syntax_map.lock();
1092        syntax_map.interpolate(&text);
1093        let syntax = syntax_map.snapshot();
1094
1095        BufferSnapshot {
1096            text,
1097            syntax,
1098            file: self.file.clone(),
1099            remote_selections: self.remote_selections.clone(),
1100            diagnostics: self.diagnostics.clone(),
1101            language: self.language.clone(),
1102            non_text_state_update_count: self.non_text_state_update_count,
1103        }
1104    }
1105
1106    pub fn branch(&mut self, cx: &mut Context<Self>) -> Entity<Self> {
1107        let this = cx.entity();
1108        cx.new(|cx| {
1109            let mut branch = Self {
1110                branch_state: Some(BufferBranchState {
1111                    base_buffer: this.clone(),
1112                    merged_operations: Default::default(),
1113                }),
1114                language: self.language.clone(),
1115                has_conflict: self.has_conflict,
1116                has_unsaved_edits: Cell::new(self.has_unsaved_edits.get_mut().clone()),
1117                _subscriptions: vec![cx.subscribe(&this, Self::on_base_buffer_event)],
1118                ..Self::build(self.text.branch(), self.file.clone(), self.capability())
1119            };
1120            if let Some(language_registry) = self.language_registry() {
1121                branch.set_language_registry(language_registry);
1122            }
1123
1124            // Reparse the branch buffer so that we get syntax highlighting immediately.
1125            branch.reparse(cx);
1126
1127            branch
1128        })
1129    }
1130
1131    pub fn preview_edits(
1132        &self,
1133        edits: Arc<[(Range<Anchor>, String)]>,
1134        cx: &App,
1135    ) -> Task<EditPreview> {
1136        let registry = self.language_registry();
1137        let language = self.language().cloned();
1138        let old_snapshot = self.text.snapshot();
1139        let mut branch_buffer = self.text.branch();
1140        let mut syntax_snapshot = self.syntax_map.lock().snapshot();
1141        cx.background_spawn(async move {
1142            if !edits.is_empty() {
1143                if let Some(language) = language.clone() {
1144                    syntax_snapshot.reparse(&old_snapshot, registry.clone(), language);
1145                }
1146
1147                branch_buffer.edit(edits.iter().cloned());
1148                let snapshot = branch_buffer.snapshot();
1149                syntax_snapshot.interpolate(&snapshot);
1150
1151                if let Some(language) = language {
1152                    syntax_snapshot.reparse(&snapshot, registry, language);
1153                }
1154            }
1155            EditPreview {
1156                old_snapshot,
1157                applied_edits_snapshot: branch_buffer.snapshot(),
1158                syntax_snapshot,
1159            }
1160        })
1161    }
1162
1163    /// Applies all of the changes in this buffer that intersect any of the
1164    /// given `ranges` to its base buffer.
1165    ///
1166    /// If `ranges` is empty, then all changes will be applied. This buffer must
1167    /// be a branch buffer to call this method.
1168    pub fn merge_into_base(&mut self, ranges: Vec<Range<usize>>, cx: &mut Context<Self>) {
1169        let Some(base_buffer) = self.base_buffer() else {
1170            debug_panic!("not a branch buffer");
1171            return;
1172        };
1173
1174        let mut ranges = if ranges.is_empty() {
1175            &[0..usize::MAX]
1176        } else {
1177            ranges.as_slice()
1178        }
1179        .iter()
1180        .peekable();
1181
1182        let mut edits = Vec::new();
1183        for edit in self.edits_since::<usize>(&base_buffer.read(cx).version()) {
1184            let mut is_included = false;
1185            while let Some(range) = ranges.peek() {
1186                if range.end < edit.new.start {
1187                    ranges.next().unwrap();
1188                } else {
1189                    if range.start <= edit.new.end {
1190                        is_included = true;
1191                    }
1192                    break;
1193                }
1194            }
1195
1196            if is_included {
1197                edits.push((
1198                    edit.old.clone(),
1199                    self.text_for_range(edit.new.clone()).collect::<String>(),
1200                ));
1201            }
1202        }
1203
1204        let operation = base_buffer.update(cx, |base_buffer, cx| {
1205            // cx.emit(BufferEvent::DiffBaseChanged);
1206            base_buffer.edit(edits, None, cx)
1207        });
1208
1209        if let Some(operation) = operation
1210            && let Some(BufferBranchState {
1211                merged_operations, ..
1212            }) = &mut self.branch_state
1213        {
1214            merged_operations.push(operation);
1215        }
1216    }
1217
1218    fn on_base_buffer_event(
1219        &mut self,
1220        _: Entity<Buffer>,
1221        event: &BufferEvent,
1222        cx: &mut Context<Self>,
1223    ) {
1224        let BufferEvent::Operation { operation, .. } = event else {
1225            return;
1226        };
1227        let Some(BufferBranchState {
1228            merged_operations, ..
1229        }) = &mut self.branch_state
1230        else {
1231            return;
1232        };
1233
1234        let mut operation_to_undo = None;
1235        if let Operation::Buffer(text::Operation::Edit(operation)) = &operation
1236            && let Ok(ix) = merged_operations.binary_search(&operation.timestamp)
1237        {
1238            merged_operations.remove(ix);
1239            operation_to_undo = Some(operation.timestamp);
1240        }
1241
1242        self.apply_ops([operation.clone()], cx);
1243
1244        if let Some(timestamp) = operation_to_undo {
1245            let counts = [(timestamp, u32::MAX)].into_iter().collect();
1246            self.undo_operations(counts, cx);
1247        }
1248    }
1249
1250    #[cfg(test)]
1251    pub(crate) fn as_text_snapshot(&self) -> &text::BufferSnapshot {
1252        &self.text
1253    }
1254
1255    /// Retrieve a snapshot of the buffer's raw text, without any
1256    /// language-related state like the syntax tree or diagnostics.
1257    pub fn text_snapshot(&self) -> text::BufferSnapshot {
1258        self.text.snapshot()
1259    }
1260
1261    /// The file associated with the buffer, if any.
1262    pub fn file(&self) -> Option<&Arc<dyn File>> {
1263        self.file.as_ref()
1264    }
1265
1266    /// The version of the buffer that was last saved or reloaded from disk.
1267    pub fn saved_version(&self) -> &clock::Global {
1268        &self.saved_version
1269    }
1270
1271    /// The mtime of the buffer's file when the buffer was last saved or reloaded from disk.
1272    pub fn saved_mtime(&self) -> Option<MTime> {
1273        self.saved_mtime
1274    }
1275
1276    /// Assign a language to the buffer.
1277    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut Context<Self>) {
1278        self.non_text_state_update_count += 1;
1279        self.syntax_map.lock().clear(&self.text);
1280        self.language = language;
1281        self.was_changed();
1282        self.reparse(cx);
1283        cx.emit(BufferEvent::LanguageChanged);
1284    }
1285
1286    /// Assign a language registry to the buffer. This allows the buffer to retrieve
1287    /// other languages if parts of the buffer are written in different languages.
1288    pub fn set_language_registry(&self, language_registry: Arc<LanguageRegistry>) {
1289        self.syntax_map
1290            .lock()
1291            .set_language_registry(language_registry);
1292    }
1293
1294    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
1295        self.syntax_map.lock().language_registry()
1296    }
1297
1298    /// Assign the line ending type to the buffer.
1299    pub fn set_line_ending(&mut self, line_ending: LineEnding, cx: &mut Context<Self>) {
1300        self.text.set_line_ending(line_ending);
1301
1302        let lamport_timestamp = self.text.lamport_clock.tick();
1303        self.send_operation(
1304            Operation::UpdateLineEnding {
1305                line_ending,
1306                lamport_timestamp,
1307            },
1308            true,
1309            cx,
1310        );
1311    }
1312
1313    /// Assign the buffer a new [`Capability`].
1314    pub fn set_capability(&mut self, capability: Capability, cx: &mut Context<Self>) {
1315        if self.capability != capability {
1316            self.capability = capability;
1317            cx.emit(BufferEvent::CapabilityChanged)
1318        }
1319    }
1320
1321    /// This method is called to signal that the buffer has been saved.
1322    pub fn did_save(
1323        &mut self,
1324        version: clock::Global,
1325        mtime: Option<MTime>,
1326        cx: &mut Context<Self>,
1327    ) {
1328        self.saved_version = version.clone();
1329        self.has_unsaved_edits.set((version, false));
1330        self.has_conflict = false;
1331        self.saved_mtime = mtime;
1332        self.was_changed();
1333        cx.emit(BufferEvent::Saved);
1334        cx.notify();
1335    }
1336
1337    /// Reloads the contents of the buffer from disk.
1338    pub fn reload(&mut self, cx: &Context<Self>) -> oneshot::Receiver<Option<Transaction>> {
1339        let (tx, rx) = futures::channel::oneshot::channel();
1340        let prev_version = self.text.version();
1341        self.reload_task = Some(cx.spawn(async move |this, cx| {
1342            let Some((new_mtime, new_text)) = this.update(cx, |this, cx| {
1343                let file = this.file.as_ref()?.as_local()?;
1344
1345                Some((file.disk_state().mtime(), file.load(cx)))
1346            })?
1347            else {
1348                return Ok(());
1349            };
1350
1351            let new_text = new_text.await?;
1352            let diff = this
1353                .update(cx, |this, cx| this.diff(new_text.clone(), cx))?
1354                .await;
1355            this.update(cx, |this, cx| {
1356                if this.version() == diff.base_version {
1357                    this.finalize_last_transaction();
1358                    this.apply_diff(diff, cx);
1359                    tx.send(this.finalize_last_transaction().cloned()).ok();
1360                    this.has_conflict = false;
1361                    this.did_reload(this.version(), this.line_ending(), new_mtime, cx);
1362                } else {
1363                    if !diff.edits.is_empty()
1364                        || this
1365                            .edits_since::<usize>(&diff.base_version)
1366                            .next()
1367                            .is_some()
1368                    {
1369                        this.has_conflict = true;
1370                    }
1371
1372                    this.did_reload(prev_version, this.line_ending(), this.saved_mtime, cx);
1373                }
1374
1375                this.reload_task.take();
1376            })
1377        }));
1378        rx
1379    }
1380
1381    /// This method is called to signal that the buffer has been reloaded.
1382    pub fn did_reload(
1383        &mut self,
1384        version: clock::Global,
1385        line_ending: LineEnding,
1386        mtime: Option<MTime>,
1387        cx: &mut Context<Self>,
1388    ) {
1389        self.saved_version = version;
1390        self.has_unsaved_edits
1391            .set((self.saved_version.clone(), false));
1392        self.text.set_line_ending(line_ending);
1393        self.saved_mtime = mtime;
1394        cx.emit(BufferEvent::Reloaded);
1395        cx.notify();
1396    }
1397
1398    /// Updates the [`File`] backing this buffer. This should be called when
1399    /// the file has changed or has been deleted.
1400    pub fn file_updated(&mut self, new_file: Arc<dyn File>, cx: &mut Context<Self>) {
1401        let was_dirty = self.is_dirty();
1402        let mut file_changed = false;
1403
1404        if let Some(old_file) = self.file.as_ref() {
1405            if new_file.path() != old_file.path() {
1406                file_changed = true;
1407            }
1408
1409            let old_state = old_file.disk_state();
1410            let new_state = new_file.disk_state();
1411            if old_state != new_state {
1412                file_changed = true;
1413                if !was_dirty && matches!(new_state, DiskState::Present { .. }) {
1414                    cx.emit(BufferEvent::ReloadNeeded)
1415                }
1416            }
1417        } else {
1418            file_changed = true;
1419        };
1420
1421        self.file = Some(new_file);
1422        if file_changed {
1423            self.was_changed();
1424            self.non_text_state_update_count += 1;
1425            if was_dirty != self.is_dirty() {
1426                cx.emit(BufferEvent::DirtyChanged);
1427            }
1428            cx.emit(BufferEvent::FileHandleChanged);
1429            cx.notify();
1430        }
1431    }
1432
1433    pub fn base_buffer(&self) -> Option<Entity<Self>> {
1434        Some(self.branch_state.as_ref()?.base_buffer.clone())
1435    }
1436
1437    /// Returns the primary [`Language`] assigned to this [`Buffer`].
1438    pub fn language(&self) -> Option<&Arc<Language>> {
1439        self.language.as_ref()
1440    }
1441
1442    /// Returns the [`Language`] at the given location.
1443    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
1444        let offset = position.to_offset(self);
1445        let mut is_first = true;
1446        let start_anchor = self.anchor_before(offset);
1447        let end_anchor = self.anchor_after(offset);
1448        self.syntax_map
1449            .lock()
1450            .layers_for_range(offset..offset, &self.text, false)
1451            .filter(|layer| {
1452                if is_first {
1453                    is_first = false;
1454                    return true;
1455                }
1456
1457                layer
1458                    .included_sub_ranges
1459                    .map(|sub_ranges| {
1460                        sub_ranges.iter().any(|sub_range| {
1461                            let is_before_start = sub_range.end.cmp(&start_anchor, self).is_lt();
1462                            let is_after_end = sub_range.start.cmp(&end_anchor, self).is_gt();
1463                            !is_before_start && !is_after_end
1464                        })
1465                    })
1466                    .unwrap_or(true)
1467            })
1468            .last()
1469            .map(|info| info.language.clone())
1470            .or_else(|| self.language.clone())
1471    }
1472
1473    /// Returns each [`Language`] for the active syntax layers at the given location.
1474    pub fn languages_at<D: ToOffset>(&self, position: D) -> Vec<Arc<Language>> {
1475        let offset = position.to_offset(self);
1476        let mut languages: Vec<Arc<Language>> = self
1477            .syntax_map
1478            .lock()
1479            .layers_for_range(offset..offset, &self.text, false)
1480            .map(|info| info.language.clone())
1481            .collect();
1482
1483        if languages.is_empty()
1484            && let Some(buffer_language) = self.language()
1485        {
1486            languages.push(buffer_language.clone());
1487        }
1488
1489        languages
1490    }
1491
1492    /// An integer version number that accounts for all updates besides
1493    /// the buffer's text itself (which is versioned via a version vector).
1494    pub fn non_text_state_update_count(&self) -> usize {
1495        self.non_text_state_update_count
1496    }
1497
1498    /// Whether the buffer is being parsed in the background.
1499    #[cfg(any(test, feature = "test-support"))]
1500    pub fn is_parsing(&self) -> bool {
1501        self.reparse.is_some()
1502    }
1503
1504    /// Indicates whether the buffer contains any regions that may be
1505    /// written in a language that hasn't been loaded yet.
1506    pub fn contains_unknown_injections(&self) -> bool {
1507        self.syntax_map.lock().contains_unknown_injections()
1508    }
1509
1510    #[cfg(any(test, feature = "test-support"))]
1511    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
1512        self.sync_parse_timeout = timeout;
1513    }
1514
1515    /// Called after an edit to synchronize the buffer's main parse tree with
1516    /// the buffer's new underlying state.
1517    ///
1518    /// Locks the syntax map and interpolates the edits since the last reparse
1519    /// into the foreground syntax tree.
1520    ///
1521    /// Then takes a stable snapshot of the syntax map before unlocking it.
1522    /// The snapshot with the interpolated edits is sent to a background thread,
1523    /// where we ask Tree-sitter to perform an incremental parse.
1524    ///
1525    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
1526    /// waiting on the parse to complete. As soon as it completes, we proceed
1527    /// synchronously, unless a 1ms timeout elapses.
1528    ///
1529    /// If we time out waiting on the parse, we spawn a second task waiting
1530    /// until the parse does complete and return with the interpolated tree still
1531    /// in the foreground. When the background parse completes, call back into
1532    /// the main thread and assign the foreground parse state.
1533    ///
1534    /// If the buffer or grammar changed since the start of the background parse,
1535    /// initiate an additional reparse recursively. To avoid concurrent parses
1536    /// for the same buffer, we only initiate a new parse if we are not already
1537    /// parsing in the background.
1538    pub fn reparse(&mut self, cx: &mut Context<Self>) {
1539        if self.reparse.is_some() {
1540            return;
1541        }
1542        let language = if let Some(language) = self.language.clone() {
1543            language
1544        } else {
1545            return;
1546        };
1547
1548        let text = self.text_snapshot();
1549        let parsed_version = self.version();
1550
1551        let mut syntax_map = self.syntax_map.lock();
1552        syntax_map.interpolate(&text);
1553        let language_registry = syntax_map.language_registry();
1554        let mut syntax_snapshot = syntax_map.snapshot();
1555        drop(syntax_map);
1556
1557        let parse_task = cx.background_spawn({
1558            let language = language.clone();
1559            let language_registry = language_registry.clone();
1560            async move {
1561                syntax_snapshot.reparse(&text, language_registry, language);
1562                syntax_snapshot
1563            }
1564        });
1565
1566        self.parse_status.0.send(ParseStatus::Parsing).unwrap();
1567        match cx
1568            .background_executor()
1569            .block_with_timeout(self.sync_parse_timeout, parse_task)
1570        {
1571            Ok(new_syntax_snapshot) => {
1572                self.did_finish_parsing(new_syntax_snapshot, cx);
1573                self.reparse = None;
1574            }
1575            Err(parse_task) => {
1576                self.reparse = Some(cx.spawn(async move |this, cx| {
1577                    let new_syntax_map = parse_task.await;
1578                    this.update(cx, move |this, cx| {
1579                        let grammar_changed =
1580                            this.language.as_ref().is_none_or(|current_language| {
1581                                !Arc::ptr_eq(&language, current_language)
1582                            });
1583                        let language_registry_changed = new_syntax_map
1584                            .contains_unknown_injections()
1585                            && language_registry.is_some_and(|registry| {
1586                                registry.version() != new_syntax_map.language_registry_version()
1587                            });
1588                        let parse_again = language_registry_changed
1589                            || grammar_changed
1590                            || this.version.changed_since(&parsed_version);
1591                        this.did_finish_parsing(new_syntax_map, cx);
1592                        this.reparse = None;
1593                        if parse_again {
1594                            this.reparse(cx);
1595                        }
1596                    })
1597                    .ok();
1598                }));
1599            }
1600        }
1601    }
1602
1603    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut Context<Self>) {
1604        self.was_changed();
1605        self.non_text_state_update_count += 1;
1606        self.syntax_map.lock().did_parse(syntax_snapshot);
1607        self.request_autoindent(cx);
1608        self.parse_status.0.send(ParseStatus::Idle).unwrap();
1609        cx.emit(BufferEvent::Reparsed);
1610        cx.notify();
1611    }
1612
1613    pub fn parse_status(&self) -> watch::Receiver<ParseStatus> {
1614        self.parse_status.1.clone()
1615    }
1616
1617    /// Assign to the buffer a set of diagnostics created by a given language server.
1618    pub fn update_diagnostics(
1619        &mut self,
1620        server_id: LanguageServerId,
1621        diagnostics: DiagnosticSet,
1622        cx: &mut Context<Self>,
1623    ) {
1624        let lamport_timestamp = self.text.lamport_clock.tick();
1625        let op = Operation::UpdateDiagnostics {
1626            server_id,
1627            diagnostics: diagnostics.iter().cloned().collect(),
1628            lamport_timestamp,
1629        };
1630
1631        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
1632        self.send_operation(op, true, cx);
1633    }
1634
1635    pub fn buffer_diagnostics(
1636        &self,
1637        for_server: Option<LanguageServerId>,
1638    ) -> Vec<&DiagnosticEntry<Anchor>> {
1639        match for_server {
1640            Some(server_id) => match self.diagnostics.binary_search_by_key(&server_id, |v| v.0) {
1641                Ok(idx) => self.diagnostics[idx].1.iter().collect(),
1642                Err(_) => Vec::new(),
1643            },
1644            None => self
1645                .diagnostics
1646                .iter()
1647                .flat_map(|(_, diagnostic_set)| diagnostic_set.iter())
1648                .collect(),
1649        }
1650    }
1651
1652    fn request_autoindent(&mut self, cx: &mut Context<Self>) {
1653        if let Some(indent_sizes) = self.compute_autoindents() {
1654            let indent_sizes = cx.background_spawn(indent_sizes);
1655            match cx
1656                .background_executor()
1657                .block_with_timeout(Duration::from_micros(500), indent_sizes)
1658            {
1659                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
1660                Err(indent_sizes) => {
1661                    self.pending_autoindent = Some(cx.spawn(async move |this, cx| {
1662                        let indent_sizes = indent_sizes.await;
1663                        this.update(cx, |this, cx| {
1664                            this.apply_autoindents(indent_sizes, cx);
1665                        })
1666                        .ok();
1667                    }));
1668                }
1669            }
1670        } else {
1671            self.autoindent_requests.clear();
1672            for tx in self.wait_for_autoindent_txs.drain(..) {
1673                tx.send(()).ok();
1674            }
1675        }
1676    }
1677
1678    fn compute_autoindents(
1679        &self,
1680    ) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>> + use<>> {
1681        let max_rows_between_yields = 100;
1682        let snapshot = self.snapshot();
1683        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
1684            return None;
1685        }
1686
1687        let autoindent_requests = self.autoindent_requests.clone();
1688        Some(async move {
1689            let mut indent_sizes = BTreeMap::<u32, (IndentSize, bool)>::new();
1690            for request in autoindent_requests {
1691                // Resolve each edited range to its row in the current buffer and in the
1692                // buffer before this batch of edits.
1693                let mut row_ranges = Vec::new();
1694                let mut old_to_new_rows = BTreeMap::new();
1695                let mut language_indent_sizes_by_new_row = Vec::new();
1696                for entry in &request.entries {
1697                    let position = entry.range.start;
1698                    let new_row = position.to_point(&snapshot).row;
1699                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
1700                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
1701
1702                    if !entry.first_line_is_new {
1703                        let old_row = position.to_point(&request.before_edit).row;
1704                        old_to_new_rows.insert(old_row, new_row);
1705                    }
1706                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
1707                }
1708
1709                // Build a map containing the suggested indentation for each of the edited lines
1710                // with respect to the state of the buffer before these edits. This map is keyed
1711                // by the rows for these lines in the current state of the buffer.
1712                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
1713                let old_edited_ranges =
1714                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
1715                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1716                let mut language_indent_size = IndentSize::default();
1717                for old_edited_range in old_edited_ranges {
1718                    let suggestions = request
1719                        .before_edit
1720                        .suggest_autoindents(old_edited_range.clone())
1721                        .into_iter()
1722                        .flatten();
1723                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1724                        if let Some(suggestion) = suggestion {
1725                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
1726
1727                            // Find the indent size based on the language for this row.
1728                            while let Some((row, size)) = language_indent_sizes.peek() {
1729                                if *row > new_row {
1730                                    break;
1731                                }
1732                                language_indent_size = *size;
1733                                language_indent_sizes.next();
1734                            }
1735
1736                            let suggested_indent = old_to_new_rows
1737                                .get(&suggestion.basis_row)
1738                                .and_then(|from_row| {
1739                                    Some(old_suggestions.get(from_row).copied()?.0)
1740                                })
1741                                .unwrap_or_else(|| {
1742                                    request
1743                                        .before_edit
1744                                        .indent_size_for_line(suggestion.basis_row)
1745                                })
1746                                .with_delta(suggestion.delta, language_indent_size);
1747                            old_suggestions
1748                                .insert(new_row, (suggested_indent, suggestion.within_error));
1749                        }
1750                    }
1751                    yield_now().await;
1752                }
1753
1754                // Compute new suggestions for each line, but only include them in the result
1755                // if they differ from the old suggestion for that line.
1756                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1757                let mut language_indent_size = IndentSize::default();
1758                for (row_range, original_indent_column) in row_ranges {
1759                    let new_edited_row_range = if request.is_block_mode {
1760                        row_range.start..row_range.start + 1
1761                    } else {
1762                        row_range.clone()
1763                    };
1764
1765                    let suggestions = snapshot
1766                        .suggest_autoindents(new_edited_row_range.clone())
1767                        .into_iter()
1768                        .flatten();
1769                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1770                        if let Some(suggestion) = suggestion {
1771                            // Find the indent size based on the language for this row.
1772                            while let Some((row, size)) = language_indent_sizes.peek() {
1773                                if *row > new_row {
1774                                    break;
1775                                }
1776                                language_indent_size = *size;
1777                                language_indent_sizes.next();
1778                            }
1779
1780                            let suggested_indent = indent_sizes
1781                                .get(&suggestion.basis_row)
1782                                .copied()
1783                                .map(|e| e.0)
1784                                .unwrap_or_else(|| {
1785                                    snapshot.indent_size_for_line(suggestion.basis_row)
1786                                })
1787                                .with_delta(suggestion.delta, language_indent_size);
1788
1789                            if old_suggestions.get(&new_row).is_none_or(
1790                                |(old_indentation, was_within_error)| {
1791                                    suggested_indent != *old_indentation
1792                                        && (!suggestion.within_error || *was_within_error)
1793                                },
1794                            ) {
1795                                indent_sizes.insert(
1796                                    new_row,
1797                                    (suggested_indent, request.ignore_empty_lines),
1798                                );
1799                            }
1800                        }
1801                    }
1802
1803                    if let (true, Some(original_indent_column)) =
1804                        (request.is_block_mode, original_indent_column)
1805                    {
1806                        let new_indent =
1807                            if let Some((indent, _)) = indent_sizes.get(&row_range.start) {
1808                                *indent
1809                            } else {
1810                                snapshot.indent_size_for_line(row_range.start)
1811                            };
1812                        let delta = new_indent.len as i64 - original_indent_column as i64;
1813                        if delta != 0 {
1814                            for row in row_range.skip(1) {
1815                                indent_sizes.entry(row).or_insert_with(|| {
1816                                    let mut size = snapshot.indent_size_for_line(row);
1817                                    if size.kind == new_indent.kind {
1818                                        match delta.cmp(&0) {
1819                                            Ordering::Greater => size.len += delta as u32,
1820                                            Ordering::Less => {
1821                                                size.len = size.len.saturating_sub(-delta as u32)
1822                                            }
1823                                            Ordering::Equal => {}
1824                                        }
1825                                    }
1826                                    (size, request.ignore_empty_lines)
1827                                });
1828                            }
1829                        }
1830                    }
1831
1832                    yield_now().await;
1833                }
1834            }
1835
1836            indent_sizes
1837                .into_iter()
1838                .filter_map(|(row, (indent, ignore_empty_lines))| {
1839                    if ignore_empty_lines && snapshot.line_len(row) == 0 {
1840                        None
1841                    } else {
1842                        Some((row, indent))
1843                    }
1844                })
1845                .collect()
1846        })
1847    }
1848
1849    fn apply_autoindents(
1850        &mut self,
1851        indent_sizes: BTreeMap<u32, IndentSize>,
1852        cx: &mut Context<Self>,
1853    ) {
1854        self.autoindent_requests.clear();
1855        for tx in self.wait_for_autoindent_txs.drain(..) {
1856            tx.send(()).ok();
1857        }
1858
1859        let edits: Vec<_> = indent_sizes
1860            .into_iter()
1861            .filter_map(|(row, indent_size)| {
1862                let current_size = indent_size_for_line(self, row);
1863                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1864            })
1865            .collect();
1866
1867        let preserve_preview = self.preserve_preview();
1868        self.edit(edits, None, cx);
1869        if preserve_preview {
1870            self.refresh_preview();
1871        }
1872    }
1873
1874    /// Create a minimal edit that will cause the given row to be indented
1875    /// with the given size. After applying this edit, the length of the line
1876    /// will always be at least `new_size.len`.
1877    pub fn edit_for_indent_size_adjustment(
1878        row: u32,
1879        current_size: IndentSize,
1880        new_size: IndentSize,
1881    ) -> Option<(Range<Point>, String)> {
1882        if new_size.kind == current_size.kind {
1883            match new_size.len.cmp(&current_size.len) {
1884                Ordering::Greater => {
1885                    let point = Point::new(row, 0);
1886                    Some((
1887                        point..point,
1888                        iter::repeat(new_size.char())
1889                            .take((new_size.len - current_size.len) as usize)
1890                            .collect::<String>(),
1891                    ))
1892                }
1893
1894                Ordering::Less => Some((
1895                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1896                    String::new(),
1897                )),
1898
1899                Ordering::Equal => None,
1900            }
1901        } else {
1902            Some((
1903                Point::new(row, 0)..Point::new(row, current_size.len),
1904                iter::repeat(new_size.char())
1905                    .take(new_size.len as usize)
1906                    .collect::<String>(),
1907            ))
1908        }
1909    }
1910
1911    /// Spawns a background task that asynchronously computes a `Diff` between the buffer's text
1912    /// and the given new text.
1913    pub fn diff(&self, mut new_text: String, cx: &App) -> Task<Diff> {
1914        let old_text = self.as_rope().clone();
1915        let base_version = self.version();
1916        cx.background_executor()
1917            .spawn_labeled(*BUFFER_DIFF_TASK, async move {
1918                let old_text = old_text.to_string();
1919                let line_ending = LineEnding::detect(&new_text);
1920                LineEnding::normalize(&mut new_text);
1921                let edits = text_diff(&old_text, &new_text);
1922                Diff {
1923                    base_version,
1924                    line_ending,
1925                    edits,
1926                }
1927            })
1928    }
1929
1930    /// Spawns a background task that searches the buffer for any whitespace
1931    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1932    pub fn remove_trailing_whitespace(&self, cx: &App) -> Task<Diff> {
1933        let old_text = self.as_rope().clone();
1934        let line_ending = self.line_ending();
1935        let base_version = self.version();
1936        cx.background_spawn(async move {
1937            let ranges = trailing_whitespace_ranges(&old_text);
1938            let empty = Arc::<str>::from("");
1939            Diff {
1940                base_version,
1941                line_ending,
1942                edits: ranges
1943                    .into_iter()
1944                    .map(|range| (range, empty.clone()))
1945                    .collect(),
1946            }
1947        })
1948    }
1949
1950    /// Ensures that the buffer ends with a single newline character, and
1951    /// no other whitespace. Skips if the buffer is empty.
1952    pub fn ensure_final_newline(&mut self, cx: &mut Context<Self>) {
1953        let len = self.len();
1954        if len == 0 {
1955            return;
1956        }
1957        let mut offset = len;
1958        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1959            let non_whitespace_len = chunk
1960                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1961                .len();
1962            offset -= chunk.len();
1963            offset += non_whitespace_len;
1964            if non_whitespace_len != 0 {
1965                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1966                    return;
1967                }
1968                break;
1969            }
1970        }
1971        self.edit([(offset..len, "\n")], None, cx);
1972    }
1973
1974    /// Applies a diff to the buffer. If the buffer has changed since the given diff was
1975    /// calculated, then adjust the diff to account for those changes, and discard any
1976    /// parts of the diff that conflict with those changes.
1977    pub fn apply_diff(&mut self, diff: Diff, cx: &mut Context<Self>) -> Option<TransactionId> {
1978        let snapshot = self.snapshot();
1979        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1980        let mut delta = 0;
1981        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1982            while let Some(edit_since) = edits_since.peek() {
1983                // If the edit occurs after a diff hunk, then it does not
1984                // affect that hunk.
1985                if edit_since.old.start > range.end {
1986                    break;
1987                }
1988                // If the edit precedes the diff hunk, then adjust the hunk
1989                // to reflect the edit.
1990                else if edit_since.old.end < range.start {
1991                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1992                    edits_since.next();
1993                }
1994                // If the edit intersects a diff hunk, then discard that hunk.
1995                else {
1996                    return None;
1997                }
1998            }
1999
2000            let start = (range.start as i64 + delta) as usize;
2001            let end = (range.end as i64 + delta) as usize;
2002            Some((start..end, new_text))
2003        });
2004
2005        self.start_transaction();
2006        self.text.set_line_ending(diff.line_ending);
2007        self.edit(adjusted_edits, None, cx);
2008        self.end_transaction(cx)
2009    }
2010
2011    pub fn has_unsaved_edits(&self) -> bool {
2012        let (last_version, has_unsaved_edits) = self.has_unsaved_edits.take();
2013
2014        if last_version == self.version {
2015            self.has_unsaved_edits
2016                .set((last_version, has_unsaved_edits));
2017            return has_unsaved_edits;
2018        }
2019
2020        let has_edits = self.has_edits_since(&self.saved_version);
2021        self.has_unsaved_edits
2022            .set((self.version.clone(), has_edits));
2023        has_edits
2024    }
2025
2026    /// Checks if the buffer has unsaved changes.
2027    pub fn is_dirty(&self) -> bool {
2028        if self.capability == Capability::ReadOnly {
2029            return false;
2030        }
2031        if self.has_conflict {
2032            return true;
2033        }
2034        match self.file.as_ref().map(|f| f.disk_state()) {
2035            Some(DiskState::New) | Some(DiskState::Deleted) => {
2036                !self.is_empty() && self.has_unsaved_edits()
2037            }
2038            _ => self.has_unsaved_edits(),
2039        }
2040    }
2041
2042    /// Checks if the buffer and its file have both changed since the buffer
2043    /// was last saved or reloaded.
2044    pub fn has_conflict(&self) -> bool {
2045        if self.has_conflict {
2046            return true;
2047        }
2048        let Some(file) = self.file.as_ref() else {
2049            return false;
2050        };
2051        match file.disk_state() {
2052            DiskState::New => false,
2053            DiskState::Present { mtime } => match self.saved_mtime {
2054                Some(saved_mtime) => {
2055                    mtime.bad_is_greater_than(saved_mtime) && self.has_unsaved_edits()
2056                }
2057                None => true,
2058            },
2059            DiskState::Deleted => false,
2060        }
2061    }
2062
2063    /// Gets a [`Subscription`] that tracks all of the changes to the buffer's text.
2064    pub fn subscribe(&mut self) -> Subscription {
2065        self.text.subscribe()
2066    }
2067
2068    /// Adds a bit to the list of bits that are set when the buffer's text changes.
2069    ///
2070    /// This allows downstream code to check if the buffer's text has changed without
2071    /// waiting for an effect cycle, which would be required if using eents.
2072    pub fn record_changes(&mut self, bit: rc::Weak<Cell<bool>>) {
2073        if let Err(ix) = self
2074            .change_bits
2075            .binary_search_by_key(&rc::Weak::as_ptr(&bit), rc::Weak::as_ptr)
2076        {
2077            self.change_bits.insert(ix, bit);
2078        }
2079    }
2080
2081    /// Set the change bit for all "listeners".
2082    fn was_changed(&mut self) {
2083        self.change_bits.retain(|change_bit| {
2084            change_bit
2085                .upgrade()
2086                .inspect(|bit| {
2087                    _ = bit.replace(true);
2088                })
2089                .is_some()
2090        });
2091    }
2092
2093    /// Starts a transaction, if one is not already in-progress. When undoing or
2094    /// redoing edits, all of the edits performed within a transaction are undone
2095    /// or redone together.
2096    pub fn start_transaction(&mut self) -> Option<TransactionId> {
2097        self.start_transaction_at(Instant::now())
2098    }
2099
2100    /// Starts a transaction, providing the current time. Subsequent transactions
2101    /// that occur within a short period of time will be grouped together. This
2102    /// is controlled by the buffer's undo grouping duration.
2103    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
2104        self.transaction_depth += 1;
2105        if self.was_dirty_before_starting_transaction.is_none() {
2106            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
2107        }
2108        self.text.start_transaction_at(now)
2109    }
2110
2111    /// Terminates the current transaction, if this is the outermost transaction.
2112    pub fn end_transaction(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2113        self.end_transaction_at(Instant::now(), cx)
2114    }
2115
2116    /// Terminates the current transaction, providing the current time. Subsequent transactions
2117    /// that occur within a short period of time will be grouped together. This
2118    /// is controlled by the buffer's undo grouping duration.
2119    pub fn end_transaction_at(
2120        &mut self,
2121        now: Instant,
2122        cx: &mut Context<Self>,
2123    ) -> Option<TransactionId> {
2124        assert!(self.transaction_depth > 0);
2125        self.transaction_depth -= 1;
2126        let was_dirty = if self.transaction_depth == 0 {
2127            self.was_dirty_before_starting_transaction.take().unwrap()
2128        } else {
2129            false
2130        };
2131        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
2132            self.did_edit(&start_version, was_dirty, cx);
2133            Some(transaction_id)
2134        } else {
2135            None
2136        }
2137    }
2138
2139    /// Manually add a transaction to the buffer's undo history.
2140    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
2141        self.text.push_transaction(transaction, now);
2142    }
2143
2144    /// Differs from `push_transaction` in that it does not clear the redo
2145    /// stack. Intended to be used to create a parent transaction to merge
2146    /// potential child transactions into.
2147    ///
2148    /// The caller is responsible for removing it from the undo history using
2149    /// `forget_transaction` if no edits are merged into it. Otherwise, if edits
2150    /// are merged into this transaction, the caller is responsible for ensuring
2151    /// the redo stack is cleared. The easiest way to ensure the redo stack is
2152    /// cleared is to create transactions with the usual `start_transaction` and
2153    /// `end_transaction` methods and merging the resulting transactions into
2154    /// the transaction created by this method
2155    pub fn push_empty_transaction(&mut self, now: Instant) -> TransactionId {
2156        self.text.push_empty_transaction(now)
2157    }
2158
2159    /// Prevent the last transaction from being grouped with any subsequent transactions,
2160    /// even if they occur with the buffer's undo grouping duration.
2161    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
2162        self.text.finalize_last_transaction()
2163    }
2164
2165    /// Manually group all changes since a given transaction.
2166    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
2167        self.text.group_until_transaction(transaction_id);
2168    }
2169
2170    /// Manually remove a transaction from the buffer's undo history
2171    pub fn forget_transaction(&mut self, transaction_id: TransactionId) -> Option<Transaction> {
2172        self.text.forget_transaction(transaction_id)
2173    }
2174
2175    /// Retrieve a transaction from the buffer's undo history
2176    pub fn get_transaction(&self, transaction_id: TransactionId) -> Option<&Transaction> {
2177        self.text.get_transaction(transaction_id)
2178    }
2179
2180    /// Manually merge two transactions in the buffer's undo history.
2181    pub fn merge_transactions(&mut self, transaction: TransactionId, destination: TransactionId) {
2182        self.text.merge_transactions(transaction, destination);
2183    }
2184
2185    /// Waits for the buffer to receive operations with the given timestamps.
2186    pub fn wait_for_edits<It: IntoIterator<Item = clock::Lamport>>(
2187        &mut self,
2188        edit_ids: It,
2189    ) -> impl Future<Output = Result<()>> + use<It> {
2190        self.text.wait_for_edits(edit_ids)
2191    }
2192
2193    /// Waits for the buffer to receive the operations necessary for resolving the given anchors.
2194    pub fn wait_for_anchors<It: IntoIterator<Item = Anchor>>(
2195        &mut self,
2196        anchors: It,
2197    ) -> impl 'static + Future<Output = Result<()>> + use<It> {
2198        self.text.wait_for_anchors(anchors)
2199    }
2200
2201    /// Waits for the buffer to receive operations up to the given version.
2202    pub fn wait_for_version(
2203        &mut self,
2204        version: clock::Global,
2205    ) -> impl Future<Output = Result<()>> + use<> {
2206        self.text.wait_for_version(version)
2207    }
2208
2209    /// Forces all futures returned by [`Buffer::wait_for_version`], [`Buffer::wait_for_edits`], or
2210    /// [`Buffer::wait_for_version`] to resolve with an error.
2211    pub fn give_up_waiting(&mut self) {
2212        self.text.give_up_waiting();
2213    }
2214
2215    pub fn wait_for_autoindent_applied(&mut self) -> Option<oneshot::Receiver<()>> {
2216        let mut rx = None;
2217        if !self.autoindent_requests.is_empty() {
2218            let channel = oneshot::channel();
2219            self.wait_for_autoindent_txs.push(channel.0);
2220            rx = Some(channel.1);
2221        }
2222        rx
2223    }
2224
2225    /// Stores a set of selections that should be broadcasted to all of the buffer's replicas.
2226    pub fn set_active_selections(
2227        &mut self,
2228        selections: Arc<[Selection<Anchor>]>,
2229        line_mode: bool,
2230        cursor_shape: CursorShape,
2231        cx: &mut Context<Self>,
2232    ) {
2233        let lamport_timestamp = self.text.lamport_clock.tick();
2234        self.remote_selections.insert(
2235            self.text.replica_id(),
2236            SelectionSet {
2237                selections: selections.clone(),
2238                lamport_timestamp,
2239                line_mode,
2240                cursor_shape,
2241            },
2242        );
2243        self.send_operation(
2244            Operation::UpdateSelections {
2245                selections,
2246                line_mode,
2247                lamport_timestamp,
2248                cursor_shape,
2249            },
2250            true,
2251            cx,
2252        );
2253        self.non_text_state_update_count += 1;
2254        cx.notify();
2255    }
2256
2257    /// Clears the selections, so that other replicas of the buffer do not see any selections for
2258    /// this replica.
2259    pub fn remove_active_selections(&mut self, cx: &mut Context<Self>) {
2260        if self
2261            .remote_selections
2262            .get(&self.text.replica_id())
2263            .is_none_or(|set| !set.selections.is_empty())
2264        {
2265            self.set_active_selections(Arc::default(), false, Default::default(), cx);
2266        }
2267    }
2268
2269    pub fn set_agent_selections(
2270        &mut self,
2271        selections: Arc<[Selection<Anchor>]>,
2272        line_mode: bool,
2273        cursor_shape: CursorShape,
2274        cx: &mut Context<Self>,
2275    ) {
2276        let lamport_timestamp = self.text.lamport_clock.tick();
2277        self.remote_selections.insert(
2278            ReplicaId::AGENT,
2279            SelectionSet {
2280                selections,
2281                lamport_timestamp,
2282                line_mode,
2283                cursor_shape,
2284            },
2285        );
2286        self.non_text_state_update_count += 1;
2287        cx.notify();
2288    }
2289
2290    pub fn remove_agent_selections(&mut self, cx: &mut Context<Self>) {
2291        self.set_agent_selections(Arc::default(), false, Default::default(), cx);
2292    }
2293
2294    /// Replaces the buffer's entire text.
2295    pub fn set_text<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2296    where
2297        T: Into<Arc<str>>,
2298    {
2299        self.autoindent_requests.clear();
2300        self.edit([(0..self.len(), text)], None, cx)
2301    }
2302
2303    /// Appends the given text to the end of the buffer.
2304    pub fn append<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2305    where
2306        T: Into<Arc<str>>,
2307    {
2308        self.edit([(self.len()..self.len(), text)], None, cx)
2309    }
2310
2311    /// Applies the given edits to the buffer. Each edit is specified as a range of text to
2312    /// delete, and a string of text to insert at that location.
2313    ///
2314    /// If an [`AutoindentMode`] is provided, then the buffer will enqueue an auto-indent
2315    /// request for the edited ranges, which will be processed when the buffer finishes
2316    /// parsing.
2317    ///
2318    /// Parsing takes place at the end of a transaction, and may compute synchronously
2319    /// or asynchronously, depending on the changes.
2320    pub fn edit<I, S, T>(
2321        &mut self,
2322        edits_iter: I,
2323        autoindent_mode: Option<AutoindentMode>,
2324        cx: &mut Context<Self>,
2325    ) -> Option<clock::Lamport>
2326    where
2327        I: IntoIterator<Item = (Range<S>, T)>,
2328        S: ToOffset,
2329        T: Into<Arc<str>>,
2330    {
2331        // Skip invalid edits and coalesce contiguous ones.
2332        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
2333
2334        for (range, new_text) in edits_iter {
2335            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
2336
2337            if range.start > range.end {
2338                mem::swap(&mut range.start, &mut range.end);
2339            }
2340            let new_text = new_text.into();
2341            if !new_text.is_empty() || !range.is_empty() {
2342                if let Some((prev_range, prev_text)) = edits.last_mut()
2343                    && prev_range.end >= range.start
2344                {
2345                    prev_range.end = cmp::max(prev_range.end, range.end);
2346                    *prev_text = format!("{prev_text}{new_text}").into();
2347                } else {
2348                    edits.push((range, new_text));
2349                }
2350            }
2351        }
2352        if edits.is_empty() {
2353            return None;
2354        }
2355
2356        self.start_transaction();
2357        self.pending_autoindent.take();
2358        let autoindent_request = autoindent_mode
2359            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
2360
2361        let edit_operation = self.text.edit(edits.iter().cloned());
2362        let edit_id = edit_operation.timestamp();
2363
2364        if let Some((before_edit, mode)) = autoindent_request {
2365            let mut delta = 0isize;
2366            let mut previous_setting = None;
2367            let entries: Vec<_> = edits
2368                .into_iter()
2369                .enumerate()
2370                .zip(&edit_operation.as_edit().unwrap().new_text)
2371                .filter(|((_, (range, _)), _)| {
2372                    let language = before_edit.language_at(range.start);
2373                    let language_id = language.map(|l| l.id());
2374                    if let Some((cached_language_id, auto_indent)) = previous_setting
2375                        && cached_language_id == language_id
2376                    {
2377                        auto_indent
2378                    } else {
2379                        // The auto-indent setting is not present in editorconfigs, hence
2380                        // we can avoid passing the file here.
2381                        let auto_indent =
2382                            language_settings(language.map(|l| l.name()), None, cx).auto_indent;
2383                        previous_setting = Some((language_id, auto_indent));
2384                        auto_indent
2385                    }
2386                })
2387                .map(|((ix, (range, _)), new_text)| {
2388                    let new_text_length = new_text.len();
2389                    let old_start = range.start.to_point(&before_edit);
2390                    let new_start = (delta + range.start as isize) as usize;
2391                    let range_len = range.end - range.start;
2392                    delta += new_text_length as isize - range_len as isize;
2393
2394                    // Decide what range of the insertion to auto-indent, and whether
2395                    // the first line of the insertion should be considered a newly-inserted line
2396                    // or an edit to an existing line.
2397                    let mut range_of_insertion_to_indent = 0..new_text_length;
2398                    let mut first_line_is_new = true;
2399
2400                    let old_line_start = before_edit.indent_size_for_line(old_start.row).len;
2401                    let old_line_end = before_edit.line_len(old_start.row);
2402
2403                    if old_start.column > old_line_start {
2404                        first_line_is_new = false;
2405                    }
2406
2407                    if !new_text.contains('\n')
2408                        && (old_start.column + (range_len as u32) < old_line_end
2409                            || old_line_end == old_line_start)
2410                    {
2411                        first_line_is_new = false;
2412                    }
2413
2414                    // When inserting text starting with a newline, avoid auto-indenting the
2415                    // previous line.
2416                    if new_text.starts_with('\n') {
2417                        range_of_insertion_to_indent.start += 1;
2418                        first_line_is_new = true;
2419                    }
2420
2421                    let mut original_indent_column = None;
2422                    if let AutoindentMode::Block {
2423                        original_indent_columns,
2424                    } = &mode
2425                    {
2426                        original_indent_column = Some(if new_text.starts_with('\n') {
2427                            indent_size_for_text(
2428                                new_text[range_of_insertion_to_indent.clone()].chars(),
2429                            )
2430                            .len
2431                        } else {
2432                            original_indent_columns
2433                                .get(ix)
2434                                .copied()
2435                                .flatten()
2436                                .unwrap_or_else(|| {
2437                                    indent_size_for_text(
2438                                        new_text[range_of_insertion_to_indent.clone()].chars(),
2439                                    )
2440                                    .len
2441                                })
2442                        });
2443
2444                        // Avoid auto-indenting the line after the edit.
2445                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
2446                            range_of_insertion_to_indent.end -= 1;
2447                        }
2448                    }
2449
2450                    AutoindentRequestEntry {
2451                        first_line_is_new,
2452                        original_indent_column,
2453                        indent_size: before_edit.language_indent_size_at(range.start, cx),
2454                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
2455                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
2456                    }
2457                })
2458                .collect();
2459
2460            if !entries.is_empty() {
2461                self.autoindent_requests.push(Arc::new(AutoindentRequest {
2462                    before_edit,
2463                    entries,
2464                    is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
2465                    ignore_empty_lines: false,
2466                }));
2467            }
2468        }
2469
2470        self.end_transaction(cx);
2471        self.send_operation(Operation::Buffer(edit_operation), true, cx);
2472        Some(edit_id)
2473    }
2474
2475    fn did_edit(&mut self, old_version: &clock::Global, was_dirty: bool, cx: &mut Context<Self>) {
2476        self.was_changed();
2477
2478        if self.edits_since::<usize>(old_version).next().is_none() {
2479            return;
2480        }
2481
2482        self.reparse(cx);
2483        cx.emit(BufferEvent::Edited);
2484        if was_dirty != self.is_dirty() {
2485            cx.emit(BufferEvent::DirtyChanged);
2486        }
2487        cx.notify();
2488    }
2489
2490    pub fn autoindent_ranges<I, T>(&mut self, ranges: I, cx: &mut Context<Self>)
2491    where
2492        I: IntoIterator<Item = Range<T>>,
2493        T: ToOffset + Copy,
2494    {
2495        let before_edit = self.snapshot();
2496        let entries = ranges
2497            .into_iter()
2498            .map(|range| AutoindentRequestEntry {
2499                range: before_edit.anchor_before(range.start)..before_edit.anchor_after(range.end),
2500                first_line_is_new: true,
2501                indent_size: before_edit.language_indent_size_at(range.start, cx),
2502                original_indent_column: None,
2503            })
2504            .collect();
2505        self.autoindent_requests.push(Arc::new(AutoindentRequest {
2506            before_edit,
2507            entries,
2508            is_block_mode: false,
2509            ignore_empty_lines: true,
2510        }));
2511        self.request_autoindent(cx);
2512    }
2513
2514    // Inserts newlines at the given position to create an empty line, returning the start of the new line.
2515    // You can also request the insertion of empty lines above and below the line starting at the returned point.
2516    pub fn insert_empty_line(
2517        &mut self,
2518        position: impl ToPoint,
2519        space_above: bool,
2520        space_below: bool,
2521        cx: &mut Context<Self>,
2522    ) -> Point {
2523        let mut position = position.to_point(self);
2524
2525        self.start_transaction();
2526
2527        self.edit(
2528            [(position..position, "\n")],
2529            Some(AutoindentMode::EachLine),
2530            cx,
2531        );
2532
2533        if position.column > 0 {
2534            position += Point::new(1, 0);
2535        }
2536
2537        if !self.is_line_blank(position.row) {
2538            self.edit(
2539                [(position..position, "\n")],
2540                Some(AutoindentMode::EachLine),
2541                cx,
2542            );
2543        }
2544
2545        if space_above && position.row > 0 && !self.is_line_blank(position.row - 1) {
2546            self.edit(
2547                [(position..position, "\n")],
2548                Some(AutoindentMode::EachLine),
2549                cx,
2550            );
2551            position.row += 1;
2552        }
2553
2554        if space_below
2555            && (position.row == self.max_point().row || !self.is_line_blank(position.row + 1))
2556        {
2557            self.edit(
2558                [(position..position, "\n")],
2559                Some(AutoindentMode::EachLine),
2560                cx,
2561            );
2562        }
2563
2564        self.end_transaction(cx);
2565
2566        position
2567    }
2568
2569    /// Applies the given remote operations to the buffer.
2570    pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I, cx: &mut Context<Self>) {
2571        self.pending_autoindent.take();
2572        let was_dirty = self.is_dirty();
2573        let old_version = self.version.clone();
2574        let mut deferred_ops = Vec::new();
2575        let buffer_ops = ops
2576            .into_iter()
2577            .filter_map(|op| match op {
2578                Operation::Buffer(op) => Some(op),
2579                _ => {
2580                    if self.can_apply_op(&op) {
2581                        self.apply_op(op, cx);
2582                    } else {
2583                        deferred_ops.push(op);
2584                    }
2585                    None
2586                }
2587            })
2588            .collect::<Vec<_>>();
2589        for operation in buffer_ops.iter() {
2590            self.send_operation(Operation::Buffer(operation.clone()), false, cx);
2591        }
2592        self.text.apply_ops(buffer_ops);
2593        self.deferred_ops.insert(deferred_ops);
2594        self.flush_deferred_ops(cx);
2595        self.did_edit(&old_version, was_dirty, cx);
2596        // Notify independently of whether the buffer was edited as the operations could include a
2597        // selection update.
2598        cx.notify();
2599    }
2600
2601    fn flush_deferred_ops(&mut self, cx: &mut Context<Self>) {
2602        let mut deferred_ops = Vec::new();
2603        for op in self.deferred_ops.drain().iter().cloned() {
2604            if self.can_apply_op(&op) {
2605                self.apply_op(op, cx);
2606            } else {
2607                deferred_ops.push(op);
2608            }
2609        }
2610        self.deferred_ops.insert(deferred_ops);
2611    }
2612
2613    pub fn has_deferred_ops(&self) -> bool {
2614        !self.deferred_ops.is_empty() || self.text.has_deferred_ops()
2615    }
2616
2617    fn can_apply_op(&self, operation: &Operation) -> bool {
2618        match operation {
2619            Operation::Buffer(_) => {
2620                unreachable!("buffer operations should never be applied at this layer")
2621            }
2622            Operation::UpdateDiagnostics {
2623                diagnostics: diagnostic_set,
2624                ..
2625            } => diagnostic_set.iter().all(|diagnostic| {
2626                self.text.can_resolve(&diagnostic.range.start)
2627                    && self.text.can_resolve(&diagnostic.range.end)
2628            }),
2629            Operation::UpdateSelections { selections, .. } => selections
2630                .iter()
2631                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
2632            Operation::UpdateCompletionTriggers { .. } | Operation::UpdateLineEnding { .. } => true,
2633        }
2634    }
2635
2636    fn apply_op(&mut self, operation: Operation, cx: &mut Context<Self>) {
2637        match operation {
2638            Operation::Buffer(_) => {
2639                unreachable!("buffer operations should never be applied at this layer")
2640            }
2641            Operation::UpdateDiagnostics {
2642                server_id,
2643                diagnostics: diagnostic_set,
2644                lamport_timestamp,
2645            } => {
2646                let snapshot = self.snapshot();
2647                self.apply_diagnostic_update(
2648                    server_id,
2649                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
2650                    lamport_timestamp,
2651                    cx,
2652                );
2653            }
2654            Operation::UpdateSelections {
2655                selections,
2656                lamport_timestamp,
2657                line_mode,
2658                cursor_shape,
2659            } => {
2660                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id)
2661                    && set.lamport_timestamp > lamport_timestamp
2662                {
2663                    return;
2664                }
2665
2666                self.remote_selections.insert(
2667                    lamport_timestamp.replica_id,
2668                    SelectionSet {
2669                        selections,
2670                        lamport_timestamp,
2671                        line_mode,
2672                        cursor_shape,
2673                    },
2674                );
2675                self.text.lamport_clock.observe(lamport_timestamp);
2676                self.non_text_state_update_count += 1;
2677            }
2678            Operation::UpdateCompletionTriggers {
2679                triggers,
2680                lamport_timestamp,
2681                server_id,
2682            } => {
2683                if triggers.is_empty() {
2684                    self.completion_triggers_per_language_server
2685                        .remove(&server_id);
2686                    self.completion_triggers = self
2687                        .completion_triggers_per_language_server
2688                        .values()
2689                        .flat_map(|triggers| triggers.iter().cloned())
2690                        .collect();
2691                } else {
2692                    self.completion_triggers_per_language_server
2693                        .insert(server_id, triggers.iter().cloned().collect());
2694                    self.completion_triggers.extend(triggers);
2695                }
2696                self.text.lamport_clock.observe(lamport_timestamp);
2697            }
2698            Operation::UpdateLineEnding {
2699                line_ending,
2700                lamport_timestamp,
2701            } => {
2702                self.text.set_line_ending(line_ending);
2703                self.text.lamport_clock.observe(lamport_timestamp);
2704            }
2705        }
2706    }
2707
2708    fn apply_diagnostic_update(
2709        &mut self,
2710        server_id: LanguageServerId,
2711        diagnostics: DiagnosticSet,
2712        lamport_timestamp: clock::Lamport,
2713        cx: &mut Context<Self>,
2714    ) {
2715        if lamport_timestamp > self.diagnostics_timestamp {
2716            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
2717            if diagnostics.is_empty() {
2718                if let Ok(ix) = ix {
2719                    self.diagnostics.remove(ix);
2720                }
2721            } else {
2722                match ix {
2723                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
2724                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
2725                };
2726            }
2727            self.diagnostics_timestamp = lamport_timestamp;
2728            self.non_text_state_update_count += 1;
2729            self.text.lamport_clock.observe(lamport_timestamp);
2730            cx.notify();
2731            cx.emit(BufferEvent::DiagnosticsUpdated);
2732        }
2733    }
2734
2735    fn send_operation(&mut self, operation: Operation, is_local: bool, cx: &mut Context<Self>) {
2736        self.was_changed();
2737        cx.emit(BufferEvent::Operation {
2738            operation,
2739            is_local,
2740        });
2741    }
2742
2743    /// Removes the selections for a given peer.
2744    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut Context<Self>) {
2745        self.remote_selections.remove(&replica_id);
2746        cx.notify();
2747    }
2748
2749    /// Undoes the most recent transaction.
2750    pub fn undo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2751        let was_dirty = self.is_dirty();
2752        let old_version = self.version.clone();
2753
2754        if let Some((transaction_id, operation)) = self.text.undo() {
2755            self.send_operation(Operation::Buffer(operation), true, cx);
2756            self.did_edit(&old_version, was_dirty, cx);
2757            Some(transaction_id)
2758        } else {
2759            None
2760        }
2761    }
2762
2763    /// Manually undoes a specific transaction in the buffer's undo history.
2764    pub fn undo_transaction(
2765        &mut self,
2766        transaction_id: TransactionId,
2767        cx: &mut Context<Self>,
2768    ) -> bool {
2769        let was_dirty = self.is_dirty();
2770        let old_version = self.version.clone();
2771        if let Some(operation) = self.text.undo_transaction(transaction_id) {
2772            self.send_operation(Operation::Buffer(operation), true, cx);
2773            self.did_edit(&old_version, was_dirty, cx);
2774            true
2775        } else {
2776            false
2777        }
2778    }
2779
2780    /// Manually undoes all changes after a given transaction in the buffer's undo history.
2781    pub fn undo_to_transaction(
2782        &mut self,
2783        transaction_id: TransactionId,
2784        cx: &mut Context<Self>,
2785    ) -> bool {
2786        let was_dirty = self.is_dirty();
2787        let old_version = self.version.clone();
2788
2789        let operations = self.text.undo_to_transaction(transaction_id);
2790        let undone = !operations.is_empty();
2791        for operation in operations {
2792            self.send_operation(Operation::Buffer(operation), true, cx);
2793        }
2794        if undone {
2795            self.did_edit(&old_version, was_dirty, cx)
2796        }
2797        undone
2798    }
2799
2800    pub fn undo_operations(&mut self, counts: HashMap<Lamport, u32>, cx: &mut Context<Buffer>) {
2801        let was_dirty = self.is_dirty();
2802        let operation = self.text.undo_operations(counts);
2803        let old_version = self.version.clone();
2804        self.send_operation(Operation::Buffer(operation), true, cx);
2805        self.did_edit(&old_version, was_dirty, cx);
2806    }
2807
2808    /// Manually redoes a specific transaction in the buffer's redo history.
2809    pub fn redo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2810        let was_dirty = self.is_dirty();
2811        let old_version = self.version.clone();
2812
2813        if let Some((transaction_id, operation)) = self.text.redo() {
2814            self.send_operation(Operation::Buffer(operation), true, cx);
2815            self.did_edit(&old_version, was_dirty, cx);
2816            Some(transaction_id)
2817        } else {
2818            None
2819        }
2820    }
2821
2822    /// Manually undoes all changes until a given transaction in the buffer's redo history.
2823    pub fn redo_to_transaction(
2824        &mut self,
2825        transaction_id: TransactionId,
2826        cx: &mut Context<Self>,
2827    ) -> bool {
2828        let was_dirty = self.is_dirty();
2829        let old_version = self.version.clone();
2830
2831        let operations = self.text.redo_to_transaction(transaction_id);
2832        let redone = !operations.is_empty();
2833        for operation in operations {
2834            self.send_operation(Operation::Buffer(operation), true, cx);
2835        }
2836        if redone {
2837            self.did_edit(&old_version, was_dirty, cx)
2838        }
2839        redone
2840    }
2841
2842    /// Override current completion triggers with the user-provided completion triggers.
2843    pub fn set_completion_triggers(
2844        &mut self,
2845        server_id: LanguageServerId,
2846        triggers: BTreeSet<String>,
2847        cx: &mut Context<Self>,
2848    ) {
2849        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
2850        if triggers.is_empty() {
2851            self.completion_triggers_per_language_server
2852                .remove(&server_id);
2853            self.completion_triggers = self
2854                .completion_triggers_per_language_server
2855                .values()
2856                .flat_map(|triggers| triggers.iter().cloned())
2857                .collect();
2858        } else {
2859            self.completion_triggers_per_language_server
2860                .insert(server_id, triggers.clone());
2861            self.completion_triggers.extend(triggers.iter().cloned());
2862        }
2863        self.send_operation(
2864            Operation::UpdateCompletionTriggers {
2865                triggers: triggers.into_iter().collect(),
2866                lamport_timestamp: self.completion_triggers_timestamp,
2867                server_id,
2868            },
2869            true,
2870            cx,
2871        );
2872        cx.notify();
2873    }
2874
2875    /// Returns a list of strings which trigger a completion menu for this language.
2876    /// Usually this is driven by LSP server which returns a list of trigger characters for completions.
2877    pub fn completion_triggers(&self) -> &BTreeSet<String> {
2878        &self.completion_triggers
2879    }
2880
2881    /// Call this directly after performing edits to prevent the preview tab
2882    /// from being dismissed by those edits. It causes `should_dismiss_preview`
2883    /// to return false until there are additional edits.
2884    pub fn refresh_preview(&mut self) {
2885        self.preview_version = self.version.clone();
2886    }
2887
2888    /// Whether we should preserve the preview status of a tab containing this buffer.
2889    pub fn preserve_preview(&self) -> bool {
2890        !self.has_edits_since(&self.preview_version)
2891    }
2892}
2893
2894#[doc(hidden)]
2895#[cfg(any(test, feature = "test-support"))]
2896impl Buffer {
2897    pub fn edit_via_marked_text(
2898        &mut self,
2899        marked_string: &str,
2900        autoindent_mode: Option<AutoindentMode>,
2901        cx: &mut Context<Self>,
2902    ) {
2903        let edits = self.edits_for_marked_text(marked_string);
2904        self.edit(edits, autoindent_mode, cx);
2905    }
2906
2907    pub fn set_group_interval(&mut self, group_interval: Duration) {
2908        self.text.set_group_interval(group_interval);
2909    }
2910
2911    pub fn randomly_edit<T>(&mut self, rng: &mut T, old_range_count: usize, cx: &mut Context<Self>)
2912    where
2913        T: rand::Rng,
2914    {
2915        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
2916        let mut last_end = None;
2917        for _ in 0..old_range_count {
2918            if last_end.is_some_and(|last_end| last_end >= self.len()) {
2919                break;
2920            }
2921
2922            let new_start = last_end.map_or(0, |last_end| last_end + 1);
2923            let mut range = self.random_byte_range(new_start, rng);
2924            if rng.random_bool(0.2) {
2925                mem::swap(&mut range.start, &mut range.end);
2926            }
2927            last_end = Some(range.end);
2928
2929            let new_text_len = rng.random_range(0..10);
2930            let mut new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
2931            new_text = new_text.to_uppercase();
2932
2933            edits.push((range, new_text));
2934        }
2935        log::info!("mutating buffer {:?} with {:?}", self.replica_id(), edits);
2936        self.edit(edits, None, cx);
2937    }
2938
2939    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut Context<Self>) {
2940        let was_dirty = self.is_dirty();
2941        let old_version = self.version.clone();
2942
2943        let ops = self.text.randomly_undo_redo(rng);
2944        if !ops.is_empty() {
2945            for op in ops {
2946                self.send_operation(Operation::Buffer(op), true, cx);
2947                self.did_edit(&old_version, was_dirty, cx);
2948            }
2949        }
2950    }
2951}
2952
2953impl EventEmitter<BufferEvent> for Buffer {}
2954
2955impl Deref for Buffer {
2956    type Target = TextBuffer;
2957
2958    fn deref(&self) -> &Self::Target {
2959        &self.text
2960    }
2961}
2962
2963impl BufferSnapshot {
2964    /// Returns [`IndentSize`] for a given line that respects user settings and
2965    /// language preferences.
2966    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
2967        indent_size_for_line(self, row)
2968    }
2969
2970    /// Returns [`IndentSize`] for a given position that respects user settings
2971    /// and language preferences.
2972    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &App) -> IndentSize {
2973        let settings = language_settings(
2974            self.language_at(position).map(|l| l.name()),
2975            self.file(),
2976            cx,
2977        );
2978        if settings.hard_tabs {
2979            IndentSize::tab()
2980        } else {
2981            IndentSize::spaces(settings.tab_size.get())
2982        }
2983    }
2984
2985    /// Retrieve the suggested indent size for all of the given rows. The unit of indentation
2986    /// is passed in as `single_indent_size`.
2987    pub fn suggested_indents(
2988        &self,
2989        rows: impl Iterator<Item = u32>,
2990        single_indent_size: IndentSize,
2991    ) -> BTreeMap<u32, IndentSize> {
2992        let mut result = BTreeMap::new();
2993
2994        for row_range in contiguous_ranges(rows, 10) {
2995            let suggestions = match self.suggest_autoindents(row_range.clone()) {
2996                Some(suggestions) => suggestions,
2997                _ => break,
2998            };
2999
3000            for (row, suggestion) in row_range.zip(suggestions) {
3001                let indent_size = if let Some(suggestion) = suggestion {
3002                    result
3003                        .get(&suggestion.basis_row)
3004                        .copied()
3005                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
3006                        .with_delta(suggestion.delta, single_indent_size)
3007                } else {
3008                    self.indent_size_for_line(row)
3009                };
3010
3011                result.insert(row, indent_size);
3012            }
3013        }
3014
3015        result
3016    }
3017
3018    fn suggest_autoindents(
3019        &self,
3020        row_range: Range<u32>,
3021    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
3022        let config = &self.language.as_ref()?.config;
3023        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
3024
3025        #[derive(Debug, Clone)]
3026        struct StartPosition {
3027            start: Point,
3028            suffix: SharedString,
3029        }
3030
3031        // Find the suggested indentation ranges based on the syntax tree.
3032        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
3033        let end = Point::new(row_range.end, 0);
3034        let range = (start..end).to_offset(&self.text);
3035        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3036            Some(&grammar.indents_config.as_ref()?.query)
3037        });
3038        let indent_configs = matches
3039            .grammars()
3040            .iter()
3041            .map(|grammar| grammar.indents_config.as_ref().unwrap())
3042            .collect::<Vec<_>>();
3043
3044        let mut indent_ranges = Vec::<Range<Point>>::new();
3045        let mut start_positions = Vec::<StartPosition>::new();
3046        let mut outdent_positions = Vec::<Point>::new();
3047        while let Some(mat) = matches.peek() {
3048            let mut start: Option<Point> = None;
3049            let mut end: Option<Point> = None;
3050
3051            let config = indent_configs[mat.grammar_index];
3052            for capture in mat.captures {
3053                if capture.index == config.indent_capture_ix {
3054                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
3055                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
3056                } else if Some(capture.index) == config.start_capture_ix {
3057                    start = Some(Point::from_ts_point(capture.node.end_position()));
3058                } else if Some(capture.index) == config.end_capture_ix {
3059                    end = Some(Point::from_ts_point(capture.node.start_position()));
3060                } else if Some(capture.index) == config.outdent_capture_ix {
3061                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
3062                } else if let Some(suffix) = config.suffixed_start_captures.get(&capture.index) {
3063                    start_positions.push(StartPosition {
3064                        start: Point::from_ts_point(capture.node.start_position()),
3065                        suffix: suffix.clone(),
3066                    });
3067                }
3068            }
3069
3070            matches.advance();
3071            if let Some((start, end)) = start.zip(end) {
3072                if start.row == end.row {
3073                    continue;
3074                }
3075                let range = start..end;
3076                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
3077                    Err(ix) => indent_ranges.insert(ix, range),
3078                    Ok(ix) => {
3079                        let prev_range = &mut indent_ranges[ix];
3080                        prev_range.end = prev_range.end.max(range.end);
3081                    }
3082                }
3083            }
3084        }
3085
3086        let mut error_ranges = Vec::<Range<Point>>::new();
3087        let mut matches = self
3088            .syntax
3089            .matches(range, &self.text, |grammar| grammar.error_query.as_ref());
3090        while let Some(mat) = matches.peek() {
3091            let node = mat.captures[0].node;
3092            let start = Point::from_ts_point(node.start_position());
3093            let end = Point::from_ts_point(node.end_position());
3094            let range = start..end;
3095            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
3096                Ok(ix) | Err(ix) => ix,
3097            };
3098            let mut end_ix = ix;
3099            while let Some(existing_range) = error_ranges.get(end_ix) {
3100                if existing_range.end < end {
3101                    end_ix += 1;
3102                } else {
3103                    break;
3104                }
3105            }
3106            error_ranges.splice(ix..end_ix, [range]);
3107            matches.advance();
3108        }
3109
3110        outdent_positions.sort();
3111        for outdent_position in outdent_positions {
3112            // find the innermost indent range containing this outdent_position
3113            // set its end to the outdent position
3114            if let Some(range_to_truncate) = indent_ranges
3115                .iter_mut()
3116                .filter(|indent_range| indent_range.contains(&outdent_position))
3117                .next_back()
3118            {
3119                range_to_truncate.end = outdent_position;
3120            }
3121        }
3122
3123        start_positions.sort_by_key(|b| b.start);
3124
3125        // Find the suggested indentation increases and decreased based on regexes.
3126        let mut regex_outdent_map = HashMap::default();
3127        let mut last_seen_suffix: HashMap<String, Vec<Point>> = HashMap::default();
3128        let mut start_positions_iter = start_positions.iter().peekable();
3129
3130        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
3131        self.for_each_line(
3132            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
3133                ..Point::new(row_range.end, 0),
3134            |row, line| {
3135                if config
3136                    .decrease_indent_pattern
3137                    .as_ref()
3138                    .is_some_and(|regex| regex.is_match(line))
3139                {
3140                    indent_change_rows.push((row, Ordering::Less));
3141                }
3142                if config
3143                    .increase_indent_pattern
3144                    .as_ref()
3145                    .is_some_and(|regex| regex.is_match(line))
3146                {
3147                    indent_change_rows.push((row + 1, Ordering::Greater));
3148                }
3149                while let Some(pos) = start_positions_iter.peek() {
3150                    if pos.start.row < row {
3151                        let pos = start_positions_iter.next().unwrap();
3152                        last_seen_suffix
3153                            .entry(pos.suffix.to_string())
3154                            .or_default()
3155                            .push(pos.start);
3156                    } else {
3157                        break;
3158                    }
3159                }
3160                for rule in &config.decrease_indent_patterns {
3161                    if rule.pattern.as_ref().is_some_and(|r| r.is_match(line)) {
3162                        let row_start_column = self.indent_size_for_line(row).len;
3163                        let basis_row = rule
3164                            .valid_after
3165                            .iter()
3166                            .filter_map(|valid_suffix| last_seen_suffix.get(valid_suffix))
3167                            .flatten()
3168                            .filter(|start_point| start_point.column <= row_start_column)
3169                            .max_by_key(|start_point| start_point.row);
3170                        if let Some(outdent_to_row) = basis_row {
3171                            regex_outdent_map.insert(row, outdent_to_row.row);
3172                        }
3173                        break;
3174                    }
3175                }
3176            },
3177        );
3178
3179        let mut indent_changes = indent_change_rows.into_iter().peekable();
3180        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
3181            prev_non_blank_row.unwrap_or(0)
3182        } else {
3183            row_range.start.saturating_sub(1)
3184        };
3185
3186        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
3187        Some(row_range.map(move |row| {
3188            let row_start = Point::new(row, self.indent_size_for_line(row).len);
3189
3190            let mut indent_from_prev_row = false;
3191            let mut outdent_from_prev_row = false;
3192            let mut outdent_to_row = u32::MAX;
3193            let mut from_regex = false;
3194
3195            while let Some((indent_row, delta)) = indent_changes.peek() {
3196                match indent_row.cmp(&row) {
3197                    Ordering::Equal => match delta {
3198                        Ordering::Less => {
3199                            from_regex = true;
3200                            outdent_from_prev_row = true
3201                        }
3202                        Ordering::Greater => {
3203                            indent_from_prev_row = true;
3204                            from_regex = true
3205                        }
3206                        _ => {}
3207                    },
3208
3209                    Ordering::Greater => break,
3210                    Ordering::Less => {}
3211                }
3212
3213                indent_changes.next();
3214            }
3215
3216            for range in &indent_ranges {
3217                if range.start.row >= row {
3218                    break;
3219                }
3220                if range.start.row == prev_row && range.end > row_start {
3221                    indent_from_prev_row = true;
3222                }
3223                if range.end > prev_row_start && range.end <= row_start {
3224                    outdent_to_row = outdent_to_row.min(range.start.row);
3225                }
3226            }
3227
3228            if let Some(basis_row) = regex_outdent_map.get(&row) {
3229                indent_from_prev_row = false;
3230                outdent_to_row = *basis_row;
3231                from_regex = true;
3232            }
3233
3234            let within_error = error_ranges
3235                .iter()
3236                .any(|e| e.start.row < row && e.end > row_start);
3237
3238            let suggestion = if outdent_to_row == prev_row
3239                || (outdent_from_prev_row && indent_from_prev_row)
3240            {
3241                Some(IndentSuggestion {
3242                    basis_row: prev_row,
3243                    delta: Ordering::Equal,
3244                    within_error: within_error && !from_regex,
3245                })
3246            } else if indent_from_prev_row {
3247                Some(IndentSuggestion {
3248                    basis_row: prev_row,
3249                    delta: Ordering::Greater,
3250                    within_error: within_error && !from_regex,
3251                })
3252            } else if outdent_to_row < prev_row {
3253                Some(IndentSuggestion {
3254                    basis_row: outdent_to_row,
3255                    delta: Ordering::Equal,
3256                    within_error: within_error && !from_regex,
3257                })
3258            } else if outdent_from_prev_row {
3259                Some(IndentSuggestion {
3260                    basis_row: prev_row,
3261                    delta: Ordering::Less,
3262                    within_error: within_error && !from_regex,
3263                })
3264            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
3265            {
3266                Some(IndentSuggestion {
3267                    basis_row: prev_row,
3268                    delta: Ordering::Equal,
3269                    within_error: within_error && !from_regex,
3270                })
3271            } else {
3272                None
3273            };
3274
3275            prev_row = row;
3276            prev_row_start = row_start;
3277            suggestion
3278        }))
3279    }
3280
3281    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
3282        while row > 0 {
3283            row -= 1;
3284            if !self.is_line_blank(row) {
3285                return Some(row);
3286            }
3287        }
3288        None
3289    }
3290
3291    fn get_highlights(&self, range: Range<usize>) -> (SyntaxMapCaptures<'_>, Vec<HighlightMap>) {
3292        let captures = self.syntax.captures(range, &self.text, |grammar| {
3293            grammar
3294                .highlights_config
3295                .as_ref()
3296                .map(|config| &config.query)
3297        });
3298        let highlight_maps = captures
3299            .grammars()
3300            .iter()
3301            .map(|grammar| grammar.highlight_map())
3302            .collect();
3303        (captures, highlight_maps)
3304    }
3305
3306    /// Iterates over chunks of text in the given range of the buffer. Text is chunked
3307    /// in an arbitrary way due to being stored in a [`Rope`](text::Rope). The text is also
3308    /// returned in chunks where each chunk has a single syntax highlighting style and
3309    /// diagnostic status.
3310    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks<'_> {
3311        let range = range.start.to_offset(self)..range.end.to_offset(self);
3312
3313        let mut syntax = None;
3314        if language_aware {
3315            syntax = Some(self.get_highlights(range.clone()));
3316        }
3317        // We want to look at diagnostic spans only when iterating over language-annotated chunks.
3318        let diagnostics = language_aware;
3319        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostics, Some(self))
3320    }
3321
3322    pub fn highlighted_text_for_range<T: ToOffset>(
3323        &self,
3324        range: Range<T>,
3325        override_style: Option<HighlightStyle>,
3326        syntax_theme: &SyntaxTheme,
3327    ) -> HighlightedText {
3328        HighlightedText::from_buffer_range(
3329            range,
3330            &self.text,
3331            &self.syntax,
3332            override_style,
3333            syntax_theme,
3334        )
3335    }
3336
3337    /// Invokes the given callback for each line of text in the given range of the buffer.
3338    /// Uses callback to avoid allocating a string for each line.
3339    fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
3340        let mut line = String::new();
3341        let mut row = range.start.row;
3342        for chunk in self
3343            .as_rope()
3344            .chunks_in_range(range.to_offset(self))
3345            .chain(["\n"])
3346        {
3347            for (newline_ix, text) in chunk.split('\n').enumerate() {
3348                if newline_ix > 0 {
3349                    callback(row, &line);
3350                    row += 1;
3351                    line.clear();
3352                }
3353                line.push_str(text);
3354            }
3355        }
3356    }
3357
3358    /// Iterates over every [`SyntaxLayer`] in the buffer.
3359    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayer<'_>> + '_ {
3360        self.syntax_layers_for_range(0..self.len(), true)
3361    }
3362
3363    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayer<'_>> {
3364        let offset = position.to_offset(self);
3365        self.syntax_layers_for_range(offset..offset, false)
3366            .filter(|l| l.node().end_byte() > offset)
3367            .last()
3368    }
3369
3370    pub fn syntax_layers_for_range<D: ToOffset>(
3371        &self,
3372        range: Range<D>,
3373        include_hidden: bool,
3374    ) -> impl Iterator<Item = SyntaxLayer<'_>> + '_ {
3375        self.syntax
3376            .layers_for_range(range, &self.text, include_hidden)
3377    }
3378
3379    pub fn smallest_syntax_layer_containing<D: ToOffset>(
3380        &self,
3381        range: Range<D>,
3382    ) -> Option<SyntaxLayer<'_>> {
3383        let range = range.to_offset(self);
3384        self.syntax
3385            .layers_for_range(range, &self.text, false)
3386            .max_by(|a, b| {
3387                if a.depth != b.depth {
3388                    a.depth.cmp(&b.depth)
3389                } else if a.offset.0 != b.offset.0 {
3390                    a.offset.0.cmp(&b.offset.0)
3391                } else {
3392                    a.node().end_byte().cmp(&b.node().end_byte()).reverse()
3393                }
3394            })
3395    }
3396
3397    /// Returns the main [`Language`].
3398    pub fn language(&self) -> Option<&Arc<Language>> {
3399        self.language.as_ref()
3400    }
3401
3402    /// Returns the [`Language`] at the given location.
3403    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
3404        self.syntax_layer_at(position)
3405            .map(|info| info.language)
3406            .or(self.language.as_ref())
3407    }
3408
3409    /// Returns the settings for the language at the given location.
3410    pub fn settings_at<'a, D: ToOffset>(
3411        &'a self,
3412        position: D,
3413        cx: &'a App,
3414    ) -> Cow<'a, LanguageSettings> {
3415        language_settings(
3416            self.language_at(position).map(|l| l.name()),
3417            self.file.as_ref(),
3418            cx,
3419        )
3420    }
3421
3422    pub fn char_classifier_at<T: ToOffset>(&self, point: T) -> CharClassifier {
3423        CharClassifier::new(self.language_scope_at(point))
3424    }
3425
3426    /// Returns the [`LanguageScope`] at the given location.
3427    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
3428        let offset = position.to_offset(self);
3429        let mut scope = None;
3430        let mut smallest_range_and_depth: Option<(Range<usize>, usize)> = None;
3431
3432        // Use the layer that has the smallest node intersecting the given point.
3433        for layer in self
3434            .syntax
3435            .layers_for_range(offset..offset, &self.text, false)
3436        {
3437            let mut cursor = layer.node().walk();
3438
3439            let mut range = None;
3440            loop {
3441                let child_range = cursor.node().byte_range();
3442                if !child_range.contains(&offset) {
3443                    break;
3444                }
3445
3446                range = Some(child_range);
3447                if cursor.goto_first_child_for_byte(offset).is_none() {
3448                    break;
3449                }
3450            }
3451
3452            if let Some(range) = range
3453                && smallest_range_and_depth.as_ref().is_none_or(
3454                    |(smallest_range, smallest_range_depth)| {
3455                        if layer.depth > *smallest_range_depth {
3456                            true
3457                        } else if layer.depth == *smallest_range_depth {
3458                            range.len() < smallest_range.len()
3459                        } else {
3460                            false
3461                        }
3462                    },
3463                )
3464            {
3465                smallest_range_and_depth = Some((range, layer.depth));
3466                scope = Some(LanguageScope {
3467                    language: layer.language.clone(),
3468                    override_id: layer.override_id(offset, &self.text),
3469                });
3470            }
3471        }
3472
3473        scope.or_else(|| {
3474            self.language.clone().map(|language| LanguageScope {
3475                language,
3476                override_id: None,
3477            })
3478        })
3479    }
3480
3481    /// Returns a tuple of the range and character kind of the word
3482    /// surrounding the given position.
3483    pub fn surrounding_word<T: ToOffset>(
3484        &self,
3485        start: T,
3486        scope_context: Option<CharScopeContext>,
3487    ) -> (Range<usize>, Option<CharKind>) {
3488        let mut start = start.to_offset(self);
3489        let mut end = start;
3490        let mut next_chars = self.chars_at(start).take(128).peekable();
3491        let mut prev_chars = self.reversed_chars_at(start).take(128).peekable();
3492
3493        let classifier = self.char_classifier_at(start).scope_context(scope_context);
3494        let word_kind = cmp::max(
3495            prev_chars.peek().copied().map(|c| classifier.kind(c)),
3496            next_chars.peek().copied().map(|c| classifier.kind(c)),
3497        );
3498
3499        for ch in prev_chars {
3500            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3501                start -= ch.len_utf8();
3502            } else {
3503                break;
3504            }
3505        }
3506
3507        for ch in next_chars {
3508            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3509                end += ch.len_utf8();
3510            } else {
3511                break;
3512            }
3513        }
3514
3515        (start..end, word_kind)
3516    }
3517
3518    /// Moves the TreeCursor to the smallest descendant or ancestor syntax node enclosing the given
3519    /// range. When `require_larger` is true, the node found must be larger than the query range.
3520    ///
3521    /// Returns true if a node was found, and false otherwise. In the `false` case the cursor will
3522    /// be moved to the root of the tree.
3523    fn goto_node_enclosing_range(
3524        cursor: &mut tree_sitter::TreeCursor,
3525        query_range: &Range<usize>,
3526        require_larger: bool,
3527    ) -> bool {
3528        let mut ascending = false;
3529        loop {
3530            let mut range = cursor.node().byte_range();
3531            if query_range.is_empty() {
3532                // When the query range is empty and the current node starts after it, move to the
3533                // previous sibling to find the node the containing node.
3534                if range.start > query_range.start {
3535                    cursor.goto_previous_sibling();
3536                    range = cursor.node().byte_range();
3537                }
3538            } else {
3539                // When the query range is non-empty and the current node ends exactly at the start,
3540                // move to the next sibling to find a node that extends beyond the start.
3541                if range.end == query_range.start {
3542                    cursor.goto_next_sibling();
3543                    range = cursor.node().byte_range();
3544                }
3545            }
3546
3547            let encloses = range.contains_inclusive(query_range)
3548                && (!require_larger || range.len() > query_range.len());
3549            if !encloses {
3550                ascending = true;
3551                if !cursor.goto_parent() {
3552                    return false;
3553                }
3554                continue;
3555            } else if ascending {
3556                return true;
3557            }
3558
3559            // Descend into the current node.
3560            if cursor
3561                .goto_first_child_for_byte(query_range.start)
3562                .is_none()
3563            {
3564                return true;
3565            }
3566        }
3567    }
3568
3569    pub fn syntax_ancestor<'a, T: ToOffset>(
3570        &'a self,
3571        range: Range<T>,
3572    ) -> Option<tree_sitter::Node<'a>> {
3573        let range = range.start.to_offset(self)..range.end.to_offset(self);
3574        let mut result: Option<tree_sitter::Node<'a>> = None;
3575        for layer in self
3576            .syntax
3577            .layers_for_range(range.clone(), &self.text, true)
3578        {
3579            let mut cursor = layer.node().walk();
3580
3581            // Find the node that both contains the range and is larger than it.
3582            if !Self::goto_node_enclosing_range(&mut cursor, &range, true) {
3583                continue;
3584            }
3585
3586            let left_node = cursor.node();
3587            let mut layer_result = left_node;
3588
3589            // For an empty range, try to find another node immediately to the right of the range.
3590            if left_node.end_byte() == range.start {
3591                let mut right_node = None;
3592                while !cursor.goto_next_sibling() {
3593                    if !cursor.goto_parent() {
3594                        break;
3595                    }
3596                }
3597
3598                while cursor.node().start_byte() == range.start {
3599                    right_node = Some(cursor.node());
3600                    if !cursor.goto_first_child() {
3601                        break;
3602                    }
3603                }
3604
3605                // If there is a candidate node on both sides of the (empty) range, then
3606                // decide between the two by favoring a named node over an anonymous token.
3607                // If both nodes are the same in that regard, favor the right one.
3608                if let Some(right_node) = right_node
3609                    && (right_node.is_named() || !left_node.is_named())
3610                {
3611                    layer_result = right_node;
3612                }
3613            }
3614
3615            if let Some(previous_result) = &result
3616                && previous_result.byte_range().len() < layer_result.byte_range().len()
3617            {
3618                continue;
3619            }
3620            result = Some(layer_result);
3621        }
3622
3623        result
3624    }
3625
3626    /// Find the previous sibling syntax node at the given range.
3627    ///
3628    /// This function locates the syntax node that precedes the node containing
3629    /// the given range. It searches hierarchically by:
3630    /// 1. Finding the node that contains the given range
3631    /// 2. Looking for the previous sibling at the same tree level
3632    /// 3. If no sibling is found, moving up to parent levels and searching for siblings
3633    ///
3634    /// Returns `None` if there is no previous sibling at any ancestor level.
3635    pub fn syntax_prev_sibling<'a, T: ToOffset>(
3636        &'a self,
3637        range: Range<T>,
3638    ) -> Option<tree_sitter::Node<'a>> {
3639        let range = range.start.to_offset(self)..range.end.to_offset(self);
3640        let mut result: Option<tree_sitter::Node<'a>> = None;
3641
3642        for layer in self
3643            .syntax
3644            .layers_for_range(range.clone(), &self.text, true)
3645        {
3646            let mut cursor = layer.node().walk();
3647
3648            // Find the node that contains the range
3649            if !Self::goto_node_enclosing_range(&mut cursor, &range, false) {
3650                continue;
3651            }
3652
3653            // Look for the previous sibling, moving up ancestor levels if needed
3654            loop {
3655                if cursor.goto_previous_sibling() {
3656                    let layer_result = cursor.node();
3657
3658                    if let Some(previous_result) = &result {
3659                        if previous_result.byte_range().end < layer_result.byte_range().end {
3660                            continue;
3661                        }
3662                    }
3663                    result = Some(layer_result);
3664                    break;
3665                }
3666
3667                // No sibling found at this level, try moving up to parent
3668                if !cursor.goto_parent() {
3669                    break;
3670                }
3671            }
3672        }
3673
3674        result
3675    }
3676
3677    /// Find the next sibling syntax node at the given range.
3678    ///
3679    /// This function locates the syntax node that follows the node containing
3680    /// the given range. It searches hierarchically by:
3681    /// 1. Finding the node that contains the given range
3682    /// 2. Looking for the next sibling at the same tree level
3683    /// 3. If no sibling is found, moving up to parent levels and searching for siblings
3684    ///
3685    /// Returns `None` if there is no next sibling at any ancestor level.
3686    pub fn syntax_next_sibling<'a, T: ToOffset>(
3687        &'a self,
3688        range: Range<T>,
3689    ) -> Option<tree_sitter::Node<'a>> {
3690        let range = range.start.to_offset(self)..range.end.to_offset(self);
3691        let mut result: Option<tree_sitter::Node<'a>> = None;
3692
3693        for layer in self
3694            .syntax
3695            .layers_for_range(range.clone(), &self.text, true)
3696        {
3697            let mut cursor = layer.node().walk();
3698
3699            // Find the node that contains the range
3700            if !Self::goto_node_enclosing_range(&mut cursor, &range, false) {
3701                continue;
3702            }
3703
3704            // Look for the next sibling, moving up ancestor levels if needed
3705            loop {
3706                if cursor.goto_next_sibling() {
3707                    let layer_result = cursor.node();
3708
3709                    if let Some(previous_result) = &result {
3710                        if previous_result.byte_range().start > layer_result.byte_range().start {
3711                            continue;
3712                        }
3713                    }
3714                    result = Some(layer_result);
3715                    break;
3716                }
3717
3718                // No sibling found at this level, try moving up to parent
3719                if !cursor.goto_parent() {
3720                    break;
3721                }
3722            }
3723        }
3724
3725        result
3726    }
3727
3728    /// Returns the root syntax node within the given row
3729    pub fn syntax_root_ancestor(&self, position: Anchor) -> Option<tree_sitter::Node<'_>> {
3730        let start_offset = position.to_offset(self);
3731
3732        let row = self.summary_for_anchor::<text::PointUtf16>(&position).row as usize;
3733
3734        let layer = self
3735            .syntax
3736            .layers_for_range(start_offset..start_offset, &self.text, true)
3737            .next()?;
3738
3739        let mut cursor = layer.node().walk();
3740
3741        // Descend to the first leaf that touches the start of the range.
3742        while cursor.goto_first_child_for_byte(start_offset).is_some() {
3743            if cursor.node().end_byte() == start_offset {
3744                cursor.goto_next_sibling();
3745            }
3746        }
3747
3748        // Ascend to the root node within the same row.
3749        while cursor.goto_parent() {
3750            if cursor.node().start_position().row != row {
3751                break;
3752            }
3753        }
3754
3755        Some(cursor.node())
3756    }
3757
3758    /// Returns the outline for the buffer.
3759    ///
3760    /// This method allows passing an optional [`SyntaxTheme`] to
3761    /// syntax-highlight the returned symbols.
3762    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Outline<Anchor> {
3763        Outline::new(self.outline_items_containing(0..self.len(), true, theme))
3764    }
3765
3766    /// Returns all the symbols that contain the given position.
3767    ///
3768    /// This method allows passing an optional [`SyntaxTheme`] to
3769    /// syntax-highlight the returned symbols.
3770    pub fn symbols_containing<T: ToOffset>(
3771        &self,
3772        position: T,
3773        theme: Option<&SyntaxTheme>,
3774    ) -> Vec<OutlineItem<Anchor>> {
3775        let position = position.to_offset(self);
3776        let start = self.clip_offset(position.saturating_sub(1), Bias::Left);
3777        let end = self.clip_offset(position + 1, Bias::Right);
3778        let mut items = self.outline_items_containing(start..end, false, theme);
3779        let mut prev_depth = None;
3780        items.retain(|item| {
3781            let result = prev_depth.is_none_or(|prev_depth| item.depth > prev_depth);
3782            prev_depth = Some(item.depth);
3783            result
3784        });
3785        items
3786    }
3787
3788    pub fn outline_range_containing<T: ToOffset>(&self, range: Range<T>) -> Option<Range<Point>> {
3789        let range = range.to_offset(self);
3790        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3791            grammar.outline_config.as_ref().map(|c| &c.query)
3792        });
3793        let configs = matches
3794            .grammars()
3795            .iter()
3796            .map(|g| g.outline_config.as_ref().unwrap())
3797            .collect::<Vec<_>>();
3798
3799        while let Some(mat) = matches.peek() {
3800            let config = &configs[mat.grammar_index];
3801            let containing_item_node = maybe!({
3802                let item_node = mat.captures.iter().find_map(|cap| {
3803                    if cap.index == config.item_capture_ix {
3804                        Some(cap.node)
3805                    } else {
3806                        None
3807                    }
3808                })?;
3809
3810                let item_byte_range = item_node.byte_range();
3811                if item_byte_range.end < range.start || item_byte_range.start > range.end {
3812                    None
3813                } else {
3814                    Some(item_node)
3815                }
3816            });
3817
3818            if let Some(item_node) = containing_item_node {
3819                return Some(
3820                    Point::from_ts_point(item_node.start_position())
3821                        ..Point::from_ts_point(item_node.end_position()),
3822                );
3823            }
3824
3825            matches.advance();
3826        }
3827        None
3828    }
3829
3830    pub fn outline_items_containing<T: ToOffset>(
3831        &self,
3832        range: Range<T>,
3833        include_extra_context: bool,
3834        theme: Option<&SyntaxTheme>,
3835    ) -> Vec<OutlineItem<Anchor>> {
3836        let range = range.to_offset(self);
3837        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3838            grammar.outline_config.as_ref().map(|c| &c.query)
3839        });
3840
3841        let mut items = Vec::new();
3842        let mut annotation_row_ranges: Vec<Range<u32>> = Vec::new();
3843        while let Some(mat) = matches.peek() {
3844            let config = matches.grammars()[mat.grammar_index]
3845                .outline_config
3846                .as_ref()
3847                .unwrap();
3848            if let Some(item) =
3849                self.next_outline_item(config, &mat, &range, include_extra_context, theme)
3850            {
3851                items.push(item);
3852            } else if let Some(capture) = mat
3853                .captures
3854                .iter()
3855                .find(|capture| Some(capture.index) == config.annotation_capture_ix)
3856            {
3857                let capture_range = capture.node.start_position()..capture.node.end_position();
3858                let mut capture_row_range =
3859                    capture_range.start.row as u32..capture_range.end.row as u32;
3860                if capture_range.end.row > capture_range.start.row && capture_range.end.column == 0
3861                {
3862                    capture_row_range.end -= 1;
3863                }
3864                if let Some(last_row_range) = annotation_row_ranges.last_mut() {
3865                    if last_row_range.end >= capture_row_range.start.saturating_sub(1) {
3866                        last_row_range.end = capture_row_range.end;
3867                    } else {
3868                        annotation_row_ranges.push(capture_row_range);
3869                    }
3870                } else {
3871                    annotation_row_ranges.push(capture_row_range);
3872                }
3873            }
3874            matches.advance();
3875        }
3876
3877        items.sort_by_key(|item| (item.range.start, Reverse(item.range.end)));
3878
3879        // Assign depths based on containment relationships and convert to anchors.
3880        let mut item_ends_stack = Vec::<Point>::new();
3881        let mut anchor_items = Vec::new();
3882        let mut annotation_row_ranges = annotation_row_ranges.into_iter().peekable();
3883        for item in items {
3884            while let Some(last_end) = item_ends_stack.last().copied() {
3885                if last_end < item.range.end {
3886                    item_ends_stack.pop();
3887                } else {
3888                    break;
3889                }
3890            }
3891
3892            let mut annotation_row_range = None;
3893            while let Some(next_annotation_row_range) = annotation_row_ranges.peek() {
3894                let row_preceding_item = item.range.start.row.saturating_sub(1);
3895                if next_annotation_row_range.end < row_preceding_item {
3896                    annotation_row_ranges.next();
3897                } else {
3898                    if next_annotation_row_range.end == row_preceding_item {
3899                        annotation_row_range = Some(next_annotation_row_range.clone());
3900                        annotation_row_ranges.next();
3901                    }
3902                    break;
3903                }
3904            }
3905
3906            anchor_items.push(OutlineItem {
3907                depth: item_ends_stack.len(),
3908                range: self.anchor_after(item.range.start)..self.anchor_before(item.range.end),
3909                text: item.text,
3910                highlight_ranges: item.highlight_ranges,
3911                name_ranges: item.name_ranges,
3912                body_range: item
3913                    .body_range
3914                    .map(|r| self.anchor_after(r.start)..self.anchor_before(r.end)),
3915                annotation_range: annotation_row_range.map(|annotation_range| {
3916                    self.anchor_after(Point::new(annotation_range.start, 0))
3917                        ..self.anchor_before(Point::new(
3918                            annotation_range.end,
3919                            self.line_len(annotation_range.end),
3920                        ))
3921                }),
3922            });
3923            item_ends_stack.push(item.range.end);
3924        }
3925
3926        anchor_items
3927    }
3928
3929    fn next_outline_item(
3930        &self,
3931        config: &OutlineConfig,
3932        mat: &SyntaxMapMatch,
3933        range: &Range<usize>,
3934        include_extra_context: bool,
3935        theme: Option<&SyntaxTheme>,
3936    ) -> Option<OutlineItem<Point>> {
3937        let item_node = mat.captures.iter().find_map(|cap| {
3938            if cap.index == config.item_capture_ix {
3939                Some(cap.node)
3940            } else {
3941                None
3942            }
3943        })?;
3944
3945        let item_byte_range = item_node.byte_range();
3946        if item_byte_range.end < range.start || item_byte_range.start > range.end {
3947            return None;
3948        }
3949        let item_point_range = Point::from_ts_point(item_node.start_position())
3950            ..Point::from_ts_point(item_node.end_position());
3951
3952        let mut open_point = None;
3953        let mut close_point = None;
3954
3955        let mut buffer_ranges = Vec::new();
3956        let mut add_to_buffer_ranges = |node: tree_sitter::Node, node_is_name| {
3957            let mut range = node.start_byte()..node.end_byte();
3958            let start = node.start_position();
3959            if node.end_position().row > start.row {
3960                range.end = range.start + self.line_len(start.row as u32) as usize - start.column;
3961            }
3962
3963            if !range.is_empty() {
3964                buffer_ranges.push((range, node_is_name));
3965            }
3966        };
3967
3968        for capture in mat.captures {
3969            if capture.index == config.name_capture_ix {
3970                add_to_buffer_ranges(capture.node, true);
3971            } else if Some(capture.index) == config.context_capture_ix
3972                || (Some(capture.index) == config.extra_context_capture_ix && include_extra_context)
3973            {
3974                add_to_buffer_ranges(capture.node, false);
3975            } else {
3976                if Some(capture.index) == config.open_capture_ix {
3977                    open_point = Some(Point::from_ts_point(capture.node.end_position()));
3978                } else if Some(capture.index) == config.close_capture_ix {
3979                    close_point = Some(Point::from_ts_point(capture.node.start_position()));
3980                }
3981            }
3982        }
3983
3984        if buffer_ranges.is_empty() {
3985            return None;
3986        }
3987
3988        let mut text = String::new();
3989        let mut highlight_ranges = Vec::new();
3990        let mut name_ranges = Vec::new();
3991        let mut chunks = self.chunks(
3992            buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
3993            true,
3994        );
3995        let mut last_buffer_range_end = 0;
3996        for (buffer_range, is_name) in buffer_ranges {
3997            let space_added = !text.is_empty() && buffer_range.start > last_buffer_range_end;
3998            if space_added {
3999                text.push(' ');
4000            }
4001            let before_append_len = text.len();
4002            let mut offset = buffer_range.start;
4003            chunks.seek(buffer_range.clone());
4004            for mut chunk in chunks.by_ref() {
4005                if chunk.text.len() > buffer_range.end - offset {
4006                    chunk.text = &chunk.text[0..(buffer_range.end - offset)];
4007                    offset = buffer_range.end;
4008                } else {
4009                    offset += chunk.text.len();
4010                }
4011                let style = chunk
4012                    .syntax_highlight_id
4013                    .zip(theme)
4014                    .and_then(|(highlight, theme)| highlight.style(theme));
4015                if let Some(style) = style {
4016                    let start = text.len();
4017                    let end = start + chunk.text.len();
4018                    highlight_ranges.push((start..end, style));
4019                }
4020                text.push_str(chunk.text);
4021                if offset >= buffer_range.end {
4022                    break;
4023                }
4024            }
4025            if is_name {
4026                let after_append_len = text.len();
4027                let start = if space_added && !name_ranges.is_empty() {
4028                    before_append_len - 1
4029                } else {
4030                    before_append_len
4031                };
4032                name_ranges.push(start..after_append_len);
4033            }
4034            last_buffer_range_end = buffer_range.end;
4035        }
4036
4037        Some(OutlineItem {
4038            depth: 0, // We'll calculate the depth later
4039            range: item_point_range,
4040            text,
4041            highlight_ranges,
4042            name_ranges,
4043            body_range: open_point.zip(close_point).map(|(start, end)| start..end),
4044            annotation_range: None,
4045        })
4046    }
4047
4048    pub fn function_body_fold_ranges<T: ToOffset>(
4049        &self,
4050        within: Range<T>,
4051    ) -> impl Iterator<Item = Range<usize>> + '_ {
4052        self.text_object_ranges(within, TreeSitterOptions::default())
4053            .filter_map(|(range, obj)| (obj == TextObject::InsideFunction).then_some(range))
4054    }
4055
4056    /// For each grammar in the language, runs the provided
4057    /// [`tree_sitter::Query`] against the given range.
4058    pub fn matches(
4059        &self,
4060        range: Range<usize>,
4061        query: fn(&Grammar) -> Option<&tree_sitter::Query>,
4062    ) -> SyntaxMapMatches<'_> {
4063        self.syntax.matches(range, self, query)
4064    }
4065
4066    pub fn all_bracket_ranges(
4067        &self,
4068        range: Range<usize>,
4069    ) -> impl Iterator<Item = BracketMatch> + '_ {
4070        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
4071            grammar.brackets_config.as_ref().map(|c| &c.query)
4072        });
4073        let configs = matches
4074            .grammars()
4075            .iter()
4076            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
4077            .collect::<Vec<_>>();
4078
4079        iter::from_fn(move || {
4080            while let Some(mat) = matches.peek() {
4081                let mut open = None;
4082                let mut close = None;
4083                let config = &configs[mat.grammar_index];
4084                let pattern = &config.patterns[mat.pattern_index];
4085                for capture in mat.captures {
4086                    if capture.index == config.open_capture_ix {
4087                        open = Some(capture.node.byte_range());
4088                    } else if capture.index == config.close_capture_ix {
4089                        close = Some(capture.node.byte_range());
4090                    }
4091                }
4092
4093                matches.advance();
4094
4095                let Some((open_range, close_range)) = open.zip(close) else {
4096                    continue;
4097                };
4098
4099                let bracket_range = open_range.start..=close_range.end;
4100                if !bracket_range.overlaps(&range) {
4101                    continue;
4102                }
4103
4104                return Some(BracketMatch {
4105                    open_range,
4106                    close_range,
4107                    newline_only: pattern.newline_only,
4108                });
4109            }
4110            None
4111        })
4112    }
4113
4114    /// Returns bracket range pairs overlapping or adjacent to `range`
4115    pub fn bracket_ranges<T: ToOffset>(
4116        &self,
4117        range: Range<T>,
4118    ) -> impl Iterator<Item = BracketMatch> + '_ {
4119        // Find bracket pairs that *inclusively* contain the given range.
4120        let range = range.start.to_previous_offset(self)..range.end.to_next_offset(self);
4121        self.all_bracket_ranges(range)
4122            .filter(|pair| !pair.newline_only)
4123    }
4124
4125    pub fn debug_variables_query<T: ToOffset>(
4126        &self,
4127        range: Range<T>,
4128    ) -> impl Iterator<Item = (Range<usize>, DebuggerTextObject)> + '_ {
4129        let range = range.start.to_previous_offset(self)..range.end.to_next_offset(self);
4130
4131        let mut matches = self.syntax.matches_with_options(
4132            range.clone(),
4133            &self.text,
4134            TreeSitterOptions::default(),
4135            |grammar| grammar.debug_variables_config.as_ref().map(|c| &c.query),
4136        );
4137
4138        let configs = matches
4139            .grammars()
4140            .iter()
4141            .map(|grammar| grammar.debug_variables_config.as_ref())
4142            .collect::<Vec<_>>();
4143
4144        let mut captures = Vec::<(Range<usize>, DebuggerTextObject)>::new();
4145
4146        iter::from_fn(move || {
4147            loop {
4148                while let Some(capture) = captures.pop() {
4149                    if capture.0.overlaps(&range) {
4150                        return Some(capture);
4151                    }
4152                }
4153
4154                let mat = matches.peek()?;
4155
4156                let Some(config) = configs[mat.grammar_index].as_ref() else {
4157                    matches.advance();
4158                    continue;
4159                };
4160
4161                for capture in mat.captures {
4162                    let Some(ix) = config
4163                        .objects_by_capture_ix
4164                        .binary_search_by_key(&capture.index, |e| e.0)
4165                        .ok()
4166                    else {
4167                        continue;
4168                    };
4169                    let text_object = config.objects_by_capture_ix[ix].1;
4170                    let byte_range = capture.node.byte_range();
4171
4172                    let mut found = false;
4173                    for (range, existing) in captures.iter_mut() {
4174                        if existing == &text_object {
4175                            range.start = range.start.min(byte_range.start);
4176                            range.end = range.end.max(byte_range.end);
4177                            found = true;
4178                            break;
4179                        }
4180                    }
4181
4182                    if !found {
4183                        captures.push((byte_range, text_object));
4184                    }
4185                }
4186
4187                matches.advance();
4188            }
4189        })
4190    }
4191
4192    pub fn text_object_ranges<T: ToOffset>(
4193        &self,
4194        range: Range<T>,
4195        options: TreeSitterOptions,
4196    ) -> impl Iterator<Item = (Range<usize>, TextObject)> + '_ {
4197        let range =
4198            range.start.to_previous_offset(self)..self.len().min(range.end.to_next_offset(self));
4199
4200        let mut matches =
4201            self.syntax
4202                .matches_with_options(range.clone(), &self.text, options, |grammar| {
4203                    grammar.text_object_config.as_ref().map(|c| &c.query)
4204                });
4205
4206        let configs = matches
4207            .grammars()
4208            .iter()
4209            .map(|grammar| grammar.text_object_config.as_ref())
4210            .collect::<Vec<_>>();
4211
4212        let mut captures = Vec::<(Range<usize>, TextObject)>::new();
4213
4214        iter::from_fn(move || {
4215            loop {
4216                while let Some(capture) = captures.pop() {
4217                    if capture.0.overlaps(&range) {
4218                        return Some(capture);
4219                    }
4220                }
4221
4222                let mat = matches.peek()?;
4223
4224                let Some(config) = configs[mat.grammar_index].as_ref() else {
4225                    matches.advance();
4226                    continue;
4227                };
4228
4229                for capture in mat.captures {
4230                    let Some(ix) = config
4231                        .text_objects_by_capture_ix
4232                        .binary_search_by_key(&capture.index, |e| e.0)
4233                        .ok()
4234                    else {
4235                        continue;
4236                    };
4237                    let text_object = config.text_objects_by_capture_ix[ix].1;
4238                    let byte_range = capture.node.byte_range();
4239
4240                    let mut found = false;
4241                    for (range, existing) in captures.iter_mut() {
4242                        if existing == &text_object {
4243                            range.start = range.start.min(byte_range.start);
4244                            range.end = range.end.max(byte_range.end);
4245                            found = true;
4246                            break;
4247                        }
4248                    }
4249
4250                    if !found {
4251                        captures.push((byte_range, text_object));
4252                    }
4253                }
4254
4255                matches.advance();
4256            }
4257        })
4258    }
4259
4260    /// Returns enclosing bracket ranges containing the given range
4261    pub fn enclosing_bracket_ranges<T: ToOffset>(
4262        &self,
4263        range: Range<T>,
4264    ) -> impl Iterator<Item = BracketMatch> + '_ {
4265        let range = range.start.to_offset(self)..range.end.to_offset(self);
4266
4267        self.bracket_ranges(range.clone()).filter(move |pair| {
4268            pair.open_range.start <= range.start && pair.close_range.end >= range.end
4269        })
4270    }
4271
4272    /// Returns the smallest enclosing bracket ranges containing the given range or None if no brackets contain range
4273    ///
4274    /// Can optionally pass a range_filter to filter the ranges of brackets to consider
4275    pub fn innermost_enclosing_bracket_ranges<T: ToOffset>(
4276        &self,
4277        range: Range<T>,
4278        range_filter: Option<&dyn Fn(Range<usize>, Range<usize>) -> bool>,
4279    ) -> Option<(Range<usize>, Range<usize>)> {
4280        let range = range.start.to_offset(self)..range.end.to_offset(self);
4281
4282        // Get the ranges of the innermost pair of brackets.
4283        let mut result: Option<(Range<usize>, Range<usize>)> = None;
4284
4285        for pair in self.enclosing_bracket_ranges(range) {
4286            if let Some(range_filter) = range_filter
4287                && !range_filter(pair.open_range.clone(), pair.close_range.clone())
4288            {
4289                continue;
4290            }
4291
4292            let len = pair.close_range.end - pair.open_range.start;
4293
4294            if let Some((existing_open, existing_close)) = &result {
4295                let existing_len = existing_close.end - existing_open.start;
4296                if len > existing_len {
4297                    continue;
4298                }
4299            }
4300
4301            result = Some((pair.open_range, pair.close_range));
4302        }
4303
4304        result
4305    }
4306
4307    /// Returns anchor ranges for any matches of the redaction query.
4308    /// The buffer can be associated with multiple languages, and the redaction query associated with each
4309    /// will be run on the relevant section of the buffer.
4310    pub fn redacted_ranges<T: ToOffset>(
4311        &self,
4312        range: Range<T>,
4313    ) -> impl Iterator<Item = Range<usize>> + '_ {
4314        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
4315        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4316            grammar
4317                .redactions_config
4318                .as_ref()
4319                .map(|config| &config.query)
4320        });
4321
4322        let configs = syntax_matches
4323            .grammars()
4324            .iter()
4325            .map(|grammar| grammar.redactions_config.as_ref())
4326            .collect::<Vec<_>>();
4327
4328        iter::from_fn(move || {
4329            let redacted_range = syntax_matches
4330                .peek()
4331                .and_then(|mat| {
4332                    configs[mat.grammar_index].and_then(|config| {
4333                        mat.captures
4334                            .iter()
4335                            .find(|capture| capture.index == config.redaction_capture_ix)
4336                    })
4337                })
4338                .map(|mat| mat.node.byte_range());
4339            syntax_matches.advance();
4340            redacted_range
4341        })
4342    }
4343
4344    pub fn injections_intersecting_range<T: ToOffset>(
4345        &self,
4346        range: Range<T>,
4347    ) -> impl Iterator<Item = (Range<usize>, &Arc<Language>)> + '_ {
4348        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
4349
4350        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4351            grammar
4352                .injection_config
4353                .as_ref()
4354                .map(|config| &config.query)
4355        });
4356
4357        let configs = syntax_matches
4358            .grammars()
4359            .iter()
4360            .map(|grammar| grammar.injection_config.as_ref())
4361            .collect::<Vec<_>>();
4362
4363        iter::from_fn(move || {
4364            let ranges = syntax_matches.peek().and_then(|mat| {
4365                let config = &configs[mat.grammar_index]?;
4366                let content_capture_range = mat.captures.iter().find_map(|capture| {
4367                    if capture.index == config.content_capture_ix {
4368                        Some(capture.node.byte_range())
4369                    } else {
4370                        None
4371                    }
4372                })?;
4373                let language = self.language_at(content_capture_range.start)?;
4374                Some((content_capture_range, language))
4375            });
4376            syntax_matches.advance();
4377            ranges
4378        })
4379    }
4380
4381    pub fn runnable_ranges(
4382        &self,
4383        offset_range: Range<usize>,
4384    ) -> impl Iterator<Item = RunnableRange> + '_ {
4385        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4386            grammar.runnable_config.as_ref().map(|config| &config.query)
4387        });
4388
4389        let test_configs = syntax_matches
4390            .grammars()
4391            .iter()
4392            .map(|grammar| grammar.runnable_config.as_ref())
4393            .collect::<Vec<_>>();
4394
4395        iter::from_fn(move || {
4396            loop {
4397                let mat = syntax_matches.peek()?;
4398
4399                let test_range = test_configs[mat.grammar_index].and_then(|test_configs| {
4400                    let mut run_range = None;
4401                    let full_range = mat.captures.iter().fold(
4402                        Range {
4403                            start: usize::MAX,
4404                            end: 0,
4405                        },
4406                        |mut acc, next| {
4407                            let byte_range = next.node.byte_range();
4408                            if acc.start > byte_range.start {
4409                                acc.start = byte_range.start;
4410                            }
4411                            if acc.end < byte_range.end {
4412                                acc.end = byte_range.end;
4413                            }
4414                            acc
4415                        },
4416                    );
4417                    if full_range.start > full_range.end {
4418                        // We did not find a full spanning range of this match.
4419                        return None;
4420                    }
4421                    let extra_captures: SmallVec<[_; 1]> =
4422                        SmallVec::from_iter(mat.captures.iter().filter_map(|capture| {
4423                            test_configs
4424                                .extra_captures
4425                                .get(capture.index as usize)
4426                                .cloned()
4427                                .and_then(|tag_name| match tag_name {
4428                                    RunnableCapture::Named(name) => {
4429                                        Some((capture.node.byte_range(), name))
4430                                    }
4431                                    RunnableCapture::Run => {
4432                                        let _ = run_range.insert(capture.node.byte_range());
4433                                        None
4434                                    }
4435                                })
4436                        }));
4437                    let run_range = run_range?;
4438                    let tags = test_configs
4439                        .query
4440                        .property_settings(mat.pattern_index)
4441                        .iter()
4442                        .filter_map(|property| {
4443                            if *property.key == *"tag" {
4444                                property
4445                                    .value
4446                                    .as_ref()
4447                                    .map(|value| RunnableTag(value.to_string().into()))
4448                            } else {
4449                                None
4450                            }
4451                        })
4452                        .collect();
4453                    let extra_captures = extra_captures
4454                        .into_iter()
4455                        .map(|(range, name)| {
4456                            (
4457                                name.to_string(),
4458                                self.text_for_range(range).collect::<String>(),
4459                            )
4460                        })
4461                        .collect();
4462                    // All tags should have the same range.
4463                    Some(RunnableRange {
4464                        run_range,
4465                        full_range,
4466                        runnable: Runnable {
4467                            tags,
4468                            language: mat.language,
4469                            buffer: self.remote_id(),
4470                        },
4471                        extra_captures,
4472                        buffer_id: self.remote_id(),
4473                    })
4474                });
4475
4476                syntax_matches.advance();
4477                if test_range.is_some() {
4478                    // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
4479                    // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
4480                    return test_range;
4481                }
4482            }
4483        })
4484    }
4485
4486    /// Returns selections for remote peers intersecting the given range.
4487    #[allow(clippy::type_complexity)]
4488    pub fn selections_in_range(
4489        &self,
4490        range: Range<Anchor>,
4491        include_local: bool,
4492    ) -> impl Iterator<
4493        Item = (
4494            ReplicaId,
4495            bool,
4496            CursorShape,
4497            impl Iterator<Item = &Selection<Anchor>> + '_,
4498        ),
4499    > + '_ {
4500        self.remote_selections
4501            .iter()
4502            .filter(move |(replica_id, set)| {
4503                (include_local || **replica_id != self.text.replica_id())
4504                    && !set.selections.is_empty()
4505            })
4506            .map(move |(replica_id, set)| {
4507                let start_ix = match set.selections.binary_search_by(|probe| {
4508                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
4509                }) {
4510                    Ok(ix) | Err(ix) => ix,
4511                };
4512                let end_ix = match set.selections.binary_search_by(|probe| {
4513                    probe.start.cmp(&range.end, self).then(Ordering::Less)
4514                }) {
4515                    Ok(ix) | Err(ix) => ix,
4516                };
4517
4518                (
4519                    *replica_id,
4520                    set.line_mode,
4521                    set.cursor_shape,
4522                    set.selections[start_ix..end_ix].iter(),
4523                )
4524            })
4525    }
4526
4527    /// Returns if the buffer contains any diagnostics.
4528    pub fn has_diagnostics(&self) -> bool {
4529        !self.diagnostics.is_empty()
4530    }
4531
4532    /// Returns all the diagnostics intersecting the given range.
4533    pub fn diagnostics_in_range<'a, T, O>(
4534        &'a self,
4535        search_range: Range<T>,
4536        reversed: bool,
4537    ) -> impl 'a + Iterator<Item = DiagnosticEntryRef<'a, O>>
4538    where
4539        T: 'a + Clone + ToOffset,
4540        O: 'a + FromAnchor,
4541    {
4542        let mut iterators: Vec<_> = self
4543            .diagnostics
4544            .iter()
4545            .map(|(_, collection)| {
4546                collection
4547                    .range::<T, text::Anchor>(search_range.clone(), self, true, reversed)
4548                    .peekable()
4549            })
4550            .collect();
4551
4552        std::iter::from_fn(move || {
4553            let (next_ix, _) = iterators
4554                .iter_mut()
4555                .enumerate()
4556                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
4557                .min_by(|(_, a), (_, b)| {
4558                    let cmp = a
4559                        .range
4560                        .start
4561                        .cmp(&b.range.start, self)
4562                        // when range is equal, sort by diagnostic severity
4563                        .then(a.diagnostic.severity.cmp(&b.diagnostic.severity))
4564                        // and stabilize order with group_id
4565                        .then(a.diagnostic.group_id.cmp(&b.diagnostic.group_id));
4566                    if reversed { cmp.reverse() } else { cmp }
4567                })?;
4568            iterators[next_ix]
4569                .next()
4570                .map(
4571                    |DiagnosticEntryRef { range, diagnostic }| DiagnosticEntryRef {
4572                        diagnostic,
4573                        range: FromAnchor::from_anchor(&range.start, self)
4574                            ..FromAnchor::from_anchor(&range.end, self),
4575                    },
4576                )
4577        })
4578    }
4579
4580    /// Raw access to the diagnostic sets. Typically `diagnostic_groups` or `diagnostic_group`
4581    /// should be used instead.
4582    pub fn diagnostic_sets(&self) -> &SmallVec<[(LanguageServerId, DiagnosticSet); 2]> {
4583        &self.diagnostics
4584    }
4585
4586    /// Returns all the diagnostic groups associated with the given
4587    /// language server ID. If no language server ID is provided,
4588    /// all diagnostics groups are returned.
4589    pub fn diagnostic_groups(
4590        &self,
4591        language_server_id: Option<LanguageServerId>,
4592    ) -> Vec<(LanguageServerId, DiagnosticGroup<'_, Anchor>)> {
4593        let mut groups = Vec::new();
4594
4595        if let Some(language_server_id) = language_server_id {
4596            if let Ok(ix) = self
4597                .diagnostics
4598                .binary_search_by_key(&language_server_id, |e| e.0)
4599            {
4600                self.diagnostics[ix]
4601                    .1
4602                    .groups(language_server_id, &mut groups, self);
4603            }
4604        } else {
4605            for (language_server_id, diagnostics) in self.diagnostics.iter() {
4606                diagnostics.groups(*language_server_id, &mut groups, self);
4607            }
4608        }
4609
4610        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
4611            let a_start = &group_a.entries[group_a.primary_ix].range.start;
4612            let b_start = &group_b.entries[group_b.primary_ix].range.start;
4613            a_start.cmp(b_start, self).then_with(|| id_a.cmp(id_b))
4614        });
4615
4616        groups
4617    }
4618
4619    /// Returns an iterator over the diagnostics for the given group.
4620    pub fn diagnostic_group<O>(
4621        &self,
4622        group_id: usize,
4623    ) -> impl Iterator<Item = DiagnosticEntryRef<'_, O>> + use<'_, O>
4624    where
4625        O: FromAnchor + 'static,
4626    {
4627        self.diagnostics
4628            .iter()
4629            .flat_map(move |(_, set)| set.group(group_id, self))
4630    }
4631
4632    /// An integer version number that accounts for all updates besides
4633    /// the buffer's text itself (which is versioned via a version vector).
4634    pub fn non_text_state_update_count(&self) -> usize {
4635        self.non_text_state_update_count
4636    }
4637
4638    /// An integer version that changes when the buffer's syntax changes.
4639    pub fn syntax_update_count(&self) -> usize {
4640        self.syntax.update_count()
4641    }
4642
4643    /// Returns a snapshot of underlying file.
4644    pub fn file(&self) -> Option<&Arc<dyn File>> {
4645        self.file.as_ref()
4646    }
4647
4648    pub fn resolve_file_path(&self, include_root: bool, cx: &App) -> Option<String> {
4649        if let Some(file) = self.file() {
4650            if file.path().file_name().is_none() || include_root {
4651                Some(file.full_path(cx).to_string_lossy().into_owned())
4652            } else {
4653                Some(file.path().display(file.path_style(cx)).to_string())
4654            }
4655        } else {
4656            None
4657        }
4658    }
4659
4660    pub fn words_in_range(&self, query: WordsQuery) -> BTreeMap<String, Range<Anchor>> {
4661        let query_str = query.fuzzy_contents;
4662        if query_str.is_some_and(|query| query.is_empty()) {
4663            return BTreeMap::default();
4664        }
4665
4666        let classifier = CharClassifier::new(self.language.clone().map(|language| LanguageScope {
4667            language,
4668            override_id: None,
4669        }));
4670
4671        let mut query_ix = 0;
4672        let query_chars = query_str.map(|query| query.chars().collect::<Vec<_>>());
4673        let query_len = query_chars.as_ref().map_or(0, |query| query.len());
4674
4675        let mut words = BTreeMap::default();
4676        let mut current_word_start_ix = None;
4677        let mut chunk_ix = query.range.start;
4678        for chunk in self.chunks(query.range, false) {
4679            for (i, c) in chunk.text.char_indices() {
4680                let ix = chunk_ix + i;
4681                if classifier.is_word(c) {
4682                    if current_word_start_ix.is_none() {
4683                        current_word_start_ix = Some(ix);
4684                    }
4685
4686                    if let Some(query_chars) = &query_chars
4687                        && query_ix < query_len
4688                        && c.to_lowercase().eq(query_chars[query_ix].to_lowercase())
4689                    {
4690                        query_ix += 1;
4691                    }
4692                    continue;
4693                } else if let Some(word_start) = current_word_start_ix.take()
4694                    && query_ix == query_len
4695                {
4696                    let word_range = self.anchor_before(word_start)..self.anchor_after(ix);
4697                    let mut word_text = self.text_for_range(word_start..ix).peekable();
4698                    let first_char = word_text
4699                        .peek()
4700                        .and_then(|first_chunk| first_chunk.chars().next());
4701                    // Skip empty and "words" starting with digits as a heuristic to reduce useless completions
4702                    if !query.skip_digits
4703                        || first_char.is_none_or(|first_char| !first_char.is_digit(10))
4704                    {
4705                        words.insert(word_text.collect(), word_range);
4706                    }
4707                }
4708                query_ix = 0;
4709            }
4710            chunk_ix += chunk.text.len();
4711        }
4712
4713        words
4714    }
4715}
4716
4717pub struct WordsQuery<'a> {
4718    /// Only returns words with all chars from the fuzzy string in them.
4719    pub fuzzy_contents: Option<&'a str>,
4720    /// Skips words that start with a digit.
4721    pub skip_digits: bool,
4722    /// Buffer offset range, to look for words.
4723    pub range: Range<usize>,
4724}
4725
4726fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
4727    indent_size_for_text(text.chars_at(Point::new(row, 0)))
4728}
4729
4730fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
4731    let mut result = IndentSize::spaces(0);
4732    for c in text {
4733        let kind = match c {
4734            ' ' => IndentKind::Space,
4735            '\t' => IndentKind::Tab,
4736            _ => break,
4737        };
4738        if result.len == 0 {
4739            result.kind = kind;
4740        }
4741        result.len += 1;
4742    }
4743    result
4744}
4745
4746impl Clone for BufferSnapshot {
4747    fn clone(&self) -> Self {
4748        Self {
4749            text: self.text.clone(),
4750            syntax: self.syntax.clone(),
4751            file: self.file.clone(),
4752            remote_selections: self.remote_selections.clone(),
4753            diagnostics: self.diagnostics.clone(),
4754            language: self.language.clone(),
4755            non_text_state_update_count: self.non_text_state_update_count,
4756        }
4757    }
4758}
4759
4760impl Deref for BufferSnapshot {
4761    type Target = text::BufferSnapshot;
4762
4763    fn deref(&self) -> &Self::Target {
4764        &self.text
4765    }
4766}
4767
4768unsafe impl Send for BufferChunks<'_> {}
4769
4770impl<'a> BufferChunks<'a> {
4771    pub(crate) fn new(
4772        text: &'a Rope,
4773        range: Range<usize>,
4774        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
4775        diagnostics: bool,
4776        buffer_snapshot: Option<&'a BufferSnapshot>,
4777    ) -> Self {
4778        let mut highlights = None;
4779        if let Some((captures, highlight_maps)) = syntax {
4780            highlights = Some(BufferChunkHighlights {
4781                captures,
4782                next_capture: None,
4783                stack: Default::default(),
4784                highlight_maps,
4785            })
4786        }
4787
4788        let diagnostic_endpoints = diagnostics.then(|| Vec::new().into_iter().peekable());
4789        let chunks = text.chunks_in_range(range.clone());
4790
4791        let mut this = BufferChunks {
4792            range,
4793            buffer_snapshot,
4794            chunks,
4795            diagnostic_endpoints,
4796            error_depth: 0,
4797            warning_depth: 0,
4798            information_depth: 0,
4799            hint_depth: 0,
4800            unnecessary_depth: 0,
4801            underline: true,
4802            highlights,
4803        };
4804        this.initialize_diagnostic_endpoints();
4805        this
4806    }
4807
4808    /// Seeks to the given byte offset in the buffer.
4809    pub fn seek(&mut self, range: Range<usize>) {
4810        let old_range = std::mem::replace(&mut self.range, range.clone());
4811        self.chunks.set_range(self.range.clone());
4812        if let Some(highlights) = self.highlights.as_mut() {
4813            if old_range.start <= self.range.start && old_range.end >= self.range.end {
4814                // Reuse existing highlights stack, as the new range is a subrange of the old one.
4815                highlights
4816                    .stack
4817                    .retain(|(end_offset, _)| *end_offset > range.start);
4818                if let Some(capture) = &highlights.next_capture
4819                    && range.start >= capture.node.start_byte()
4820                {
4821                    let next_capture_end = capture.node.end_byte();
4822                    if range.start < next_capture_end {
4823                        highlights.stack.push((
4824                            next_capture_end,
4825                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
4826                        ));
4827                    }
4828                    highlights.next_capture.take();
4829                }
4830            } else if let Some(snapshot) = self.buffer_snapshot {
4831                let (captures, highlight_maps) = snapshot.get_highlights(self.range.clone());
4832                *highlights = BufferChunkHighlights {
4833                    captures,
4834                    next_capture: None,
4835                    stack: Default::default(),
4836                    highlight_maps,
4837                };
4838            } else {
4839                // We cannot obtain new highlights for a language-aware buffer iterator, as we don't have a buffer snapshot.
4840                // Seeking such BufferChunks is not supported.
4841                debug_assert!(
4842                    false,
4843                    "Attempted to seek on a language-aware buffer iterator without associated buffer snapshot"
4844                );
4845            }
4846
4847            highlights.captures.set_byte_range(self.range.clone());
4848            self.initialize_diagnostic_endpoints();
4849        }
4850    }
4851
4852    fn initialize_diagnostic_endpoints(&mut self) {
4853        if let Some(diagnostics) = self.diagnostic_endpoints.as_mut()
4854            && let Some(buffer) = self.buffer_snapshot
4855        {
4856            let mut diagnostic_endpoints = Vec::new();
4857            for entry in buffer.diagnostics_in_range::<_, usize>(self.range.clone(), false) {
4858                diagnostic_endpoints.push(DiagnosticEndpoint {
4859                    offset: entry.range.start,
4860                    is_start: true,
4861                    severity: entry.diagnostic.severity,
4862                    is_unnecessary: entry.diagnostic.is_unnecessary,
4863                    underline: entry.diagnostic.underline,
4864                });
4865                diagnostic_endpoints.push(DiagnosticEndpoint {
4866                    offset: entry.range.end,
4867                    is_start: false,
4868                    severity: entry.diagnostic.severity,
4869                    is_unnecessary: entry.diagnostic.is_unnecessary,
4870                    underline: entry.diagnostic.underline,
4871                });
4872            }
4873            diagnostic_endpoints
4874                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
4875            *diagnostics = diagnostic_endpoints.into_iter().peekable();
4876            self.hint_depth = 0;
4877            self.error_depth = 0;
4878            self.warning_depth = 0;
4879            self.information_depth = 0;
4880        }
4881    }
4882
4883    /// The current byte offset in the buffer.
4884    pub fn offset(&self) -> usize {
4885        self.range.start
4886    }
4887
4888    pub fn range(&self) -> Range<usize> {
4889        self.range.clone()
4890    }
4891
4892    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
4893        let depth = match endpoint.severity {
4894            DiagnosticSeverity::ERROR => &mut self.error_depth,
4895            DiagnosticSeverity::WARNING => &mut self.warning_depth,
4896            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
4897            DiagnosticSeverity::HINT => &mut self.hint_depth,
4898            _ => return,
4899        };
4900        if endpoint.is_start {
4901            *depth += 1;
4902        } else {
4903            *depth -= 1;
4904        }
4905
4906        if endpoint.is_unnecessary {
4907            if endpoint.is_start {
4908                self.unnecessary_depth += 1;
4909            } else {
4910                self.unnecessary_depth -= 1;
4911            }
4912        }
4913    }
4914
4915    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
4916        if self.error_depth > 0 {
4917            Some(DiagnosticSeverity::ERROR)
4918        } else if self.warning_depth > 0 {
4919            Some(DiagnosticSeverity::WARNING)
4920        } else if self.information_depth > 0 {
4921            Some(DiagnosticSeverity::INFORMATION)
4922        } else if self.hint_depth > 0 {
4923            Some(DiagnosticSeverity::HINT)
4924        } else {
4925            None
4926        }
4927    }
4928
4929    fn current_code_is_unnecessary(&self) -> bool {
4930        self.unnecessary_depth > 0
4931    }
4932}
4933
4934impl<'a> Iterator for BufferChunks<'a> {
4935    type Item = Chunk<'a>;
4936
4937    fn next(&mut self) -> Option<Self::Item> {
4938        let mut next_capture_start = usize::MAX;
4939        let mut next_diagnostic_endpoint = usize::MAX;
4940
4941        if let Some(highlights) = self.highlights.as_mut() {
4942            while let Some((parent_capture_end, _)) = highlights.stack.last() {
4943                if *parent_capture_end <= self.range.start {
4944                    highlights.stack.pop();
4945                } else {
4946                    break;
4947                }
4948            }
4949
4950            if highlights.next_capture.is_none() {
4951                highlights.next_capture = highlights.captures.next();
4952            }
4953
4954            while let Some(capture) = highlights.next_capture.as_ref() {
4955                if self.range.start < capture.node.start_byte() {
4956                    next_capture_start = capture.node.start_byte();
4957                    break;
4958                } else {
4959                    let highlight_id =
4960                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
4961                    highlights
4962                        .stack
4963                        .push((capture.node.end_byte(), highlight_id));
4964                    highlights.next_capture = highlights.captures.next();
4965                }
4966            }
4967        }
4968
4969        let mut diagnostic_endpoints = std::mem::take(&mut self.diagnostic_endpoints);
4970        if let Some(diagnostic_endpoints) = diagnostic_endpoints.as_mut() {
4971            while let Some(endpoint) = diagnostic_endpoints.peek().copied() {
4972                if endpoint.offset <= self.range.start {
4973                    self.update_diagnostic_depths(endpoint);
4974                    diagnostic_endpoints.next();
4975                    self.underline = endpoint.underline;
4976                } else {
4977                    next_diagnostic_endpoint = endpoint.offset;
4978                    break;
4979                }
4980            }
4981        }
4982        self.diagnostic_endpoints = diagnostic_endpoints;
4983
4984        if let Some(ChunkBitmaps {
4985            text: chunk,
4986            chars: chars_map,
4987            tabs,
4988        }) = self.chunks.peek_with_bitmaps()
4989        {
4990            let chunk_start = self.range.start;
4991            let mut chunk_end = (self.chunks.offset() + chunk.len())
4992                .min(next_capture_start)
4993                .min(next_diagnostic_endpoint);
4994            let mut highlight_id = None;
4995            if let Some(highlights) = self.highlights.as_ref()
4996                && let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last()
4997            {
4998                chunk_end = chunk_end.min(*parent_capture_end);
4999                highlight_id = Some(*parent_highlight_id);
5000            }
5001            let bit_start = chunk_start - self.chunks.offset();
5002            let bit_end = chunk_end - self.chunks.offset();
5003
5004            let slice = &chunk[bit_start..bit_end];
5005
5006            let mask = 1u128.unbounded_shl(bit_end as u32).wrapping_sub(1);
5007            let tabs = (tabs >> bit_start) & mask;
5008            let chars = (chars_map >> bit_start) & mask;
5009
5010            self.range.start = chunk_end;
5011            if self.range.start == self.chunks.offset() + chunk.len() {
5012                self.chunks.next().unwrap();
5013            }
5014
5015            Some(Chunk {
5016                text: slice,
5017                syntax_highlight_id: highlight_id,
5018                underline: self.underline,
5019                diagnostic_severity: self.current_diagnostic_severity(),
5020                is_unnecessary: self.current_code_is_unnecessary(),
5021                tabs,
5022                chars,
5023                ..Chunk::default()
5024            })
5025        } else {
5026            None
5027        }
5028    }
5029}
5030
5031impl operation_queue::Operation for Operation {
5032    fn lamport_timestamp(&self) -> clock::Lamport {
5033        match self {
5034            Operation::Buffer(_) => {
5035                unreachable!("buffer operations should never be deferred at this layer")
5036            }
5037            Operation::UpdateDiagnostics {
5038                lamport_timestamp, ..
5039            }
5040            | Operation::UpdateSelections {
5041                lamport_timestamp, ..
5042            }
5043            | Operation::UpdateCompletionTriggers {
5044                lamport_timestamp, ..
5045            }
5046            | Operation::UpdateLineEnding {
5047                lamport_timestamp, ..
5048            } => *lamport_timestamp,
5049        }
5050    }
5051}
5052
5053impl Default for Diagnostic {
5054    fn default() -> Self {
5055        Self {
5056            source: Default::default(),
5057            source_kind: DiagnosticSourceKind::Other,
5058            code: None,
5059            code_description: None,
5060            severity: DiagnosticSeverity::ERROR,
5061            message: Default::default(),
5062            markdown: None,
5063            group_id: 0,
5064            is_primary: false,
5065            is_disk_based: false,
5066            is_unnecessary: false,
5067            underline: true,
5068            data: None,
5069        }
5070    }
5071}
5072
5073impl IndentSize {
5074    /// Returns an [`IndentSize`] representing the given spaces.
5075    pub fn spaces(len: u32) -> Self {
5076        Self {
5077            len,
5078            kind: IndentKind::Space,
5079        }
5080    }
5081
5082    /// Returns an [`IndentSize`] representing a tab.
5083    pub fn tab() -> Self {
5084        Self {
5085            len: 1,
5086            kind: IndentKind::Tab,
5087        }
5088    }
5089
5090    /// An iterator over the characters represented by this [`IndentSize`].
5091    pub fn chars(&self) -> impl Iterator<Item = char> {
5092        iter::repeat(self.char()).take(self.len as usize)
5093    }
5094
5095    /// The character representation of this [`IndentSize`].
5096    pub fn char(&self) -> char {
5097        match self.kind {
5098            IndentKind::Space => ' ',
5099            IndentKind::Tab => '\t',
5100        }
5101    }
5102
5103    /// Consumes the current [`IndentSize`] and returns a new one that has
5104    /// been shrunk or enlarged by the given size along the given direction.
5105    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
5106        match direction {
5107            Ordering::Less => {
5108                if self.kind == size.kind && self.len >= size.len {
5109                    self.len -= size.len;
5110                }
5111            }
5112            Ordering::Equal => {}
5113            Ordering::Greater => {
5114                if self.len == 0 {
5115                    self = size;
5116                } else if self.kind == size.kind {
5117                    self.len += size.len;
5118                }
5119            }
5120        }
5121        self
5122    }
5123
5124    pub fn len_with_expanded_tabs(&self, tab_size: NonZeroU32) -> usize {
5125        match self.kind {
5126            IndentKind::Space => self.len as usize,
5127            IndentKind::Tab => self.len as usize * tab_size.get() as usize,
5128        }
5129    }
5130}
5131
5132#[cfg(any(test, feature = "test-support"))]
5133pub struct TestFile {
5134    pub path: Arc<RelPath>,
5135    pub root_name: String,
5136    pub local_root: Option<PathBuf>,
5137}
5138
5139#[cfg(any(test, feature = "test-support"))]
5140impl File for TestFile {
5141    fn path(&self) -> &Arc<RelPath> {
5142        &self.path
5143    }
5144
5145    fn full_path(&self, _: &gpui::App) -> PathBuf {
5146        PathBuf::from(self.root_name.clone()).join(self.path.as_std_path())
5147    }
5148
5149    fn as_local(&self) -> Option<&dyn LocalFile> {
5150        if self.local_root.is_some() {
5151            Some(self)
5152        } else {
5153            None
5154        }
5155    }
5156
5157    fn disk_state(&self) -> DiskState {
5158        unimplemented!()
5159    }
5160
5161    fn file_name<'a>(&'a self, _: &'a gpui::App) -> &'a str {
5162        self.path().file_name().unwrap_or(self.root_name.as_ref())
5163    }
5164
5165    fn worktree_id(&self, _: &App) -> WorktreeId {
5166        WorktreeId::from_usize(0)
5167    }
5168
5169    fn to_proto(&self, _: &App) -> rpc::proto::File {
5170        unimplemented!()
5171    }
5172
5173    fn is_private(&self) -> bool {
5174        false
5175    }
5176
5177    fn path_style(&self, _cx: &App) -> PathStyle {
5178        PathStyle::local()
5179    }
5180}
5181
5182#[cfg(any(test, feature = "test-support"))]
5183impl LocalFile for TestFile {
5184    fn abs_path(&self, _cx: &App) -> PathBuf {
5185        PathBuf::from(self.local_root.as_ref().unwrap())
5186            .join(&self.root_name)
5187            .join(self.path.as_std_path())
5188    }
5189
5190    fn load(&self, _cx: &App) -> Task<Result<String>> {
5191        unimplemented!()
5192    }
5193
5194    fn load_bytes(&self, _cx: &App) -> Task<Result<Vec<u8>>> {
5195        unimplemented!()
5196    }
5197}
5198
5199pub(crate) fn contiguous_ranges(
5200    values: impl Iterator<Item = u32>,
5201    max_len: usize,
5202) -> impl Iterator<Item = Range<u32>> {
5203    let mut values = values;
5204    let mut current_range: Option<Range<u32>> = None;
5205    std::iter::from_fn(move || {
5206        loop {
5207            if let Some(value) = values.next() {
5208                if let Some(range) = &mut current_range
5209                    && value == range.end
5210                    && range.len() < max_len
5211                {
5212                    range.end += 1;
5213                    continue;
5214                }
5215
5216                let prev_range = current_range.clone();
5217                current_range = Some(value..(value + 1));
5218                if prev_range.is_some() {
5219                    return prev_range;
5220                }
5221            } else {
5222                return current_range.take();
5223            }
5224        }
5225    })
5226}
5227
5228#[derive(Default, Debug)]
5229pub struct CharClassifier {
5230    scope: Option<LanguageScope>,
5231    scope_context: Option<CharScopeContext>,
5232    ignore_punctuation: bool,
5233}
5234
5235impl CharClassifier {
5236    pub fn new(scope: Option<LanguageScope>) -> Self {
5237        Self {
5238            scope,
5239            scope_context: None,
5240            ignore_punctuation: false,
5241        }
5242    }
5243
5244    pub fn scope_context(self, scope_context: Option<CharScopeContext>) -> Self {
5245        Self {
5246            scope_context,
5247            ..self
5248        }
5249    }
5250
5251    pub fn ignore_punctuation(self, ignore_punctuation: bool) -> Self {
5252        Self {
5253            ignore_punctuation,
5254            ..self
5255        }
5256    }
5257
5258    pub fn is_whitespace(&self, c: char) -> bool {
5259        self.kind(c) == CharKind::Whitespace
5260    }
5261
5262    pub fn is_word(&self, c: char) -> bool {
5263        self.kind(c) == CharKind::Word
5264    }
5265
5266    pub fn is_punctuation(&self, c: char) -> bool {
5267        self.kind(c) == CharKind::Punctuation
5268    }
5269
5270    pub fn kind_with(&self, c: char, ignore_punctuation: bool) -> CharKind {
5271        if c.is_alphanumeric() || c == '_' {
5272            return CharKind::Word;
5273        }
5274
5275        if let Some(scope) = &self.scope {
5276            let characters = match self.scope_context {
5277                Some(CharScopeContext::Completion) => scope.completion_query_characters(),
5278                Some(CharScopeContext::LinkedEdit) => scope.linked_edit_characters(),
5279                None => scope.word_characters(),
5280            };
5281            if let Some(characters) = characters
5282                && characters.contains(&c)
5283            {
5284                return CharKind::Word;
5285            }
5286        }
5287
5288        if c.is_whitespace() {
5289            return CharKind::Whitespace;
5290        }
5291
5292        if ignore_punctuation {
5293            CharKind::Word
5294        } else {
5295            CharKind::Punctuation
5296        }
5297    }
5298
5299    pub fn kind(&self, c: char) -> CharKind {
5300        self.kind_with(c, self.ignore_punctuation)
5301    }
5302}
5303
5304/// Find all of the ranges of whitespace that occur at the ends of lines
5305/// in the given rope.
5306///
5307/// This could also be done with a regex search, but this implementation
5308/// avoids copying text.
5309pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
5310    let mut ranges = Vec::new();
5311
5312    let mut offset = 0;
5313    let mut prev_chunk_trailing_whitespace_range = 0..0;
5314    for chunk in rope.chunks() {
5315        let mut prev_line_trailing_whitespace_range = 0..0;
5316        for (i, line) in chunk.split('\n').enumerate() {
5317            let line_end_offset = offset + line.len();
5318            let trimmed_line_len = line.trim_end_matches([' ', '\t']).len();
5319            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
5320
5321            if i == 0 && trimmed_line_len == 0 {
5322                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
5323            }
5324            if !prev_line_trailing_whitespace_range.is_empty() {
5325                ranges.push(prev_line_trailing_whitespace_range);
5326            }
5327
5328            offset = line_end_offset + 1;
5329            prev_line_trailing_whitespace_range = trailing_whitespace_range;
5330        }
5331
5332        offset -= 1;
5333        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
5334    }
5335
5336    if !prev_chunk_trailing_whitespace_range.is_empty() {
5337        ranges.push(prev_chunk_trailing_whitespace_range);
5338    }
5339
5340    ranges
5341}