buffer.rs

   1use crate::{
   2    DebuggerTextObject, LanguageScope, Outline, OutlineConfig, RunnableCapture, RunnableTag,
   3    TextObject, TreeSitterOptions,
   4    diagnostic_set::{DiagnosticEntry, 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};
  21pub use clock::ReplicaId;
  22use clock::{AGENT_REPLICA_ID, Lamport};
  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    ffi::OsStr,
  45    future::Future,
  46    iter::{self, Iterator, Peekable},
  47    mem,
  48    num::NonZeroU32,
  49    ops::{Deref, Range},
  50    path::{Path, PathBuf},
  51    rc,
  52    sync::{Arc, LazyLock},
  53    time::{Duration, Instant},
  54    vec,
  55};
  56use sum_tree::TreeMap;
  57use text::operation_queue::OperationQueue;
  58use text::*;
  59pub use text::{
  60    Anchor, Bias, Buffer as TextBuffer, BufferId, BufferSnapshot as TextBufferSnapshot, Edit,
  61    LineIndent, OffsetRangeExt, OffsetUtf16, Patch, Point, PointUtf16, Rope, Selection,
  62    SelectionGoal, Subscription, TextDimension, TextSummary, ToOffset, ToOffsetUtf16, ToPoint,
  63    ToPointUtf16, Transaction, TransactionId, Unclipped,
  64};
  65use theme::{ActiveTheme as _, SyntaxTheme};
  66#[cfg(any(test, feature = "test-support"))]
  67use util::RandomCharIter;
  68use util::{RangeExt, debug_panic, maybe};
  69
  70#[cfg(any(test, feature = "test-support"))]
  71pub use {tree_sitter_python, tree_sitter_rust, tree_sitter_typescript};
  72
  73pub use lsp::DiagnosticSeverity;
  74
  75/// A label for the background task spawned by the buffer to compute
  76/// a diff against the contents of its file.
  77pub static BUFFER_DIFF_TASK: LazyLock<TaskLabel> = LazyLock::new(TaskLabel::new);
  78
  79/// Indicate whether a [`Buffer`] has permissions to edit.
  80#[derive(PartialEq, Clone, Copy, Debug)]
  81pub enum Capability {
  82    /// The buffer is a mutable replica.
  83    ReadWrite,
  84    /// The buffer is a read-only replica.
  85    ReadOnly,
  86}
  87
  88pub type BufferRow = u32;
  89
  90/// An in-memory representation of a source code file, including its text,
  91/// syntax trees, git status, and diagnostics.
  92pub struct Buffer {
  93    text: TextBuffer,
  94    branch_state: Option<BufferBranchState>,
  95    /// Filesystem state, `None` when there is no path.
  96    file: Option<Arc<dyn File>>,
  97    /// The mtime of the file when this buffer was last loaded from
  98    /// or saved to disk.
  99    saved_mtime: Option<MTime>,
 100    /// The version vector when this buffer was last loaded from
 101    /// or saved to disk.
 102    saved_version: clock::Global,
 103    preview_version: clock::Global,
 104    transaction_depth: usize,
 105    was_dirty_before_starting_transaction: Option<bool>,
 106    reload_task: Option<Task<Result<()>>>,
 107    language: Option<Arc<Language>>,
 108    autoindent_requests: Vec<Arc<AutoindentRequest>>,
 109    wait_for_autoindent_txs: Vec<oneshot::Sender<()>>,
 110    pending_autoindent: Option<Task<()>>,
 111    sync_parse_timeout: Duration,
 112    syntax_map: Mutex<SyntaxMap>,
 113    reparse: Option<Task<()>>,
 114    parse_status: (watch::Sender<ParseStatus>, watch::Receiver<ParseStatus>),
 115    non_text_state_update_count: usize,
 116    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 117    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 118    diagnostics_timestamp: clock::Lamport,
 119    completion_triggers: BTreeSet<String>,
 120    completion_triggers_per_language_server: HashMap<LanguageServerId, BTreeSet<String>>,
 121    completion_triggers_timestamp: clock::Lamport,
 122    deferred_ops: OperationQueue<Operation>,
 123    capability: Capability,
 124    has_conflict: bool,
 125    /// Memoize calls to has_changes_since(saved_version).
 126    /// The contents of a cell are (self.version, has_changes) at the time of a last call.
 127    has_unsaved_edits: Cell<(clock::Global, bool)>,
 128    change_bits: Vec<rc::Weak<Cell<bool>>>,
 129    _subscriptions: Vec<gpui::Subscription>,
 130}
 131
 132#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 133pub enum ParseStatus {
 134    Idle,
 135    Parsing,
 136}
 137
 138struct BufferBranchState {
 139    base_buffer: Entity<Buffer>,
 140    merged_operations: Vec<Lamport>,
 141}
 142
 143/// An immutable, cheaply cloneable representation of a fixed
 144/// state of a buffer.
 145pub struct BufferSnapshot {
 146    pub text: text::BufferSnapshot,
 147    pub syntax: SyntaxSnapshot,
 148    file: Option<Arc<dyn File>>,
 149    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 150    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 151    language: Option<Arc<Language>>,
 152    non_text_state_update_count: usize,
 153}
 154
 155/// The kind and amount of indentation in a particular line. For now,
 156/// assumes that indentation is all the same character.
 157#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 158pub struct IndentSize {
 159    /// The number of bytes that comprise the indentation.
 160    pub len: u32,
 161    /// The kind of whitespace used for indentation.
 162    pub kind: IndentKind,
 163}
 164
 165/// A whitespace character that's used for indentation.
 166#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 167pub enum IndentKind {
 168    /// An ASCII space character.
 169    #[default]
 170    Space,
 171    /// An ASCII tab character.
 172    Tab,
 173}
 174
 175/// The shape of a selection cursor.
 176#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
 177pub enum CursorShape {
 178    /// A vertical bar
 179    #[default]
 180    Bar,
 181    /// A block that surrounds the following character
 182    Block,
 183    /// An underline that runs along the following character
 184    Underline,
 185    /// A box drawn around the following character
 186    Hollow,
 187}
 188
 189impl From<settings::CursorShape> for CursorShape {
 190    fn from(shape: settings::CursorShape) -> Self {
 191        match shape {
 192            settings::CursorShape::Bar => CursorShape::Bar,
 193            settings::CursorShape::Block => CursorShape::Block,
 194            settings::CursorShape::Underline => CursorShape::Underline,
 195            settings::CursorShape::Hollow => CursorShape::Hollow,
 196        }
 197    }
 198}
 199
 200#[derive(Clone, Debug)]
 201struct SelectionSet {
 202    line_mode: bool,
 203    cursor_shape: CursorShape,
 204    selections: Arc<[Selection<Anchor>]>,
 205    lamport_timestamp: clock::Lamport,
 206}
 207
 208/// A diagnostic associated with a certain range of a buffer.
 209#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 210pub struct Diagnostic {
 211    /// The name of the service that produced this diagnostic.
 212    pub source: Option<String>,
 213    /// A machine-readable code that identifies this diagnostic.
 214    pub code: Option<NumberOrString>,
 215    pub code_description: Option<lsp::Uri>,
 216    /// Whether this diagnostic is a hint, warning, or error.
 217    pub severity: DiagnosticSeverity,
 218    /// The human-readable message associated with this diagnostic.
 219    pub message: String,
 220    /// The human-readable message (in markdown format)
 221    pub markdown: Option<String>,
 222    /// An id that identifies the group to which this diagnostic belongs.
 223    ///
 224    /// When a language server produces a diagnostic with
 225    /// one or more associated diagnostics, those diagnostics are all
 226    /// assigned a single group ID.
 227    pub group_id: usize,
 228    /// Whether this diagnostic is the primary diagnostic for its group.
 229    ///
 230    /// In a given group, the primary diagnostic is the top-level diagnostic
 231    /// returned by the language server. The non-primary diagnostics are the
 232    /// associated diagnostics.
 233    pub is_primary: bool,
 234    /// Whether this diagnostic is considered to originate from an analysis of
 235    /// files on disk, as opposed to any unsaved buffer contents. This is a
 236    /// property of a given diagnostic source, and is configured for a given
 237    /// language server via the [`LspAdapter::disk_based_diagnostic_sources`](crate::LspAdapter::disk_based_diagnostic_sources) method
 238    /// for the language server.
 239    pub is_disk_based: bool,
 240    /// Whether this diagnostic marks unnecessary code.
 241    pub is_unnecessary: bool,
 242    /// Quick separation of diagnostics groups based by their source.
 243    pub source_kind: DiagnosticSourceKind,
 244    /// Data from language server that produced this diagnostic. Passed back to the LS when we request code actions for this diagnostic.
 245    pub data: Option<Value>,
 246    /// Whether to underline the corresponding text range in the editor.
 247    pub underline: bool,
 248}
 249
 250#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
 251pub enum DiagnosticSourceKind {
 252    Pulled,
 253    Pushed,
 254    Other,
 255}
 256
 257/// An operation used to synchronize this buffer with its other replicas.
 258#[derive(Clone, Debug, PartialEq)]
 259pub enum Operation {
 260    /// A text operation.
 261    Buffer(text::Operation),
 262
 263    /// An update to the buffer's diagnostics.
 264    UpdateDiagnostics {
 265        /// The id of the language server that produced the new diagnostics.
 266        server_id: LanguageServerId,
 267        /// The diagnostics.
 268        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 269        /// The buffer's lamport timestamp.
 270        lamport_timestamp: clock::Lamport,
 271    },
 272
 273    /// An update to the most recent selections in this buffer.
 274    UpdateSelections {
 275        /// The selections.
 276        selections: Arc<[Selection<Anchor>]>,
 277        /// The buffer's lamport timestamp.
 278        lamport_timestamp: clock::Lamport,
 279        /// Whether the selections are in 'line mode'.
 280        line_mode: bool,
 281        /// The [`CursorShape`] associated with these selections.
 282        cursor_shape: CursorShape,
 283    },
 284
 285    /// An update to the characters that should trigger autocompletion
 286    /// for this buffer.
 287    UpdateCompletionTriggers {
 288        /// The characters that trigger autocompletion.
 289        triggers: Vec<String>,
 290        /// The buffer's lamport timestamp.
 291        lamport_timestamp: clock::Lamport,
 292        /// The language server ID.
 293        server_id: LanguageServerId,
 294    },
 295
 296    /// An update to the line ending type of this buffer.
 297    UpdateLineEnding {
 298        /// The line ending type.
 299        line_ending: LineEnding,
 300        /// The buffer's lamport timestamp.
 301        lamport_timestamp: clock::Lamport,
 302    },
 303}
 304
 305/// An event that occurs in a buffer.
 306#[derive(Clone, Debug, PartialEq)]
 307pub enum BufferEvent {
 308    /// The buffer was changed in a way that must be
 309    /// propagated to its other replicas.
 310    Operation {
 311        operation: Operation,
 312        is_local: bool,
 313    },
 314    /// The buffer was edited.
 315    Edited,
 316    /// The buffer's `dirty` bit changed.
 317    DirtyChanged,
 318    /// The buffer was saved.
 319    Saved,
 320    /// The buffer's file was changed on disk.
 321    FileHandleChanged,
 322    /// The buffer was reloaded.
 323    Reloaded,
 324    /// The buffer is in need of a reload
 325    ReloadNeeded,
 326    /// The buffer's language was changed.
 327    LanguageChanged,
 328    /// The buffer's syntax trees were updated.
 329    Reparsed,
 330    /// The buffer's diagnostics were updated.
 331    DiagnosticsUpdated,
 332    /// The buffer gained or lost editing capabilities.
 333    CapabilityChanged,
 334}
 335
 336/// The file associated with a buffer.
 337pub trait File: Send + Sync + Any {
 338    /// Returns the [`LocalFile`] associated with this file, if the
 339    /// file is local.
 340    fn as_local(&self) -> Option<&dyn LocalFile>;
 341
 342    /// Returns whether this file is local.
 343    fn is_local(&self) -> bool {
 344        self.as_local().is_some()
 345    }
 346
 347    /// Returns whether the file is new, exists in storage, or has been deleted. Includes metadata
 348    /// only available in some states, such as modification time.
 349    fn disk_state(&self) -> DiskState;
 350
 351    /// Returns the path of this file relative to the worktree's root directory.
 352    fn path(&self) -> &Arc<Path>;
 353
 354    /// Returns the path of this file relative to the worktree's parent directory (this means it
 355    /// includes the name of the worktree's root folder).
 356    fn full_path(&self, cx: &App) -> PathBuf;
 357
 358    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 359    /// of its worktree, then this method will return the name of the worktree itself.
 360    fn file_name<'a>(&'a self, cx: &'a App) -> &'a OsStr;
 361
 362    /// Returns the id of the worktree to which this file belongs.
 363    ///
 364    /// This is needed for looking up project-specific settings.
 365    fn worktree_id(&self, cx: &App) -> WorktreeId;
 366
 367    /// Converts this file into a protobuf message.
 368    fn to_proto(&self, cx: &App) -> rpc::proto::File;
 369
 370    /// Return whether Zed considers this to be a private file.
 371    fn is_private(&self) -> bool;
 372}
 373
 374/// The file's storage status - whether it's stored (`Present`), and if so when it was last
 375/// modified. In the case where the file is not stored, it can be either `New` or `Deleted`. In the
 376/// UI these two states are distinguished. For example, the buffer tab does not display a deletion
 377/// indicator for new files.
 378#[derive(Copy, Clone, Debug, PartialEq)]
 379pub enum DiskState {
 380    /// File created in Zed that has not been saved.
 381    New,
 382    /// File present on the filesystem.
 383    Present { mtime: MTime },
 384    /// Deleted file that was previously present.
 385    Deleted,
 386}
 387
 388impl DiskState {
 389    /// Returns the file's last known modification time on disk.
 390    pub fn mtime(self) -> Option<MTime> {
 391        match self {
 392            DiskState::New => None,
 393            DiskState::Present { mtime } => Some(mtime),
 394            DiskState::Deleted => None,
 395        }
 396    }
 397
 398    pub fn exists(&self) -> bool {
 399        match self {
 400            DiskState::New => false,
 401            DiskState::Present { .. } => true,
 402            DiskState::Deleted => false,
 403        }
 404    }
 405}
 406
 407/// The file associated with a buffer, in the case where the file is on the local disk.
 408pub trait LocalFile: File {
 409    /// Returns the absolute path of this file
 410    fn abs_path(&self, cx: &App) -> PathBuf;
 411
 412    /// Loads the file contents from disk and returns them as a UTF-8 encoded string.
 413    fn load(&self, cx: &App) -> Task<Result<String>>;
 414
 415    /// Loads the file's contents from disk.
 416    fn load_bytes(&self, cx: &App) -> Task<Result<Vec<u8>>>;
 417}
 418
 419/// The auto-indent behavior associated with an editing operation.
 420/// For some editing operations, each affected line of text has its
 421/// indentation recomputed. For other operations, the entire block
 422/// of edited text is adjusted uniformly.
 423#[derive(Clone, Debug)]
 424pub enum AutoindentMode {
 425    /// Indent each line of inserted text.
 426    EachLine,
 427    /// Apply the same indentation adjustment to all of the lines
 428    /// in a given insertion.
 429    Block {
 430        /// The original indentation column of the first line of each
 431        /// insertion, if it has been copied.
 432        ///
 433        /// Knowing this makes it possible to preserve the relative indentation
 434        /// of every line in the insertion from when it was copied.
 435        ///
 436        /// If the original indent column is `a`, and the first line of insertion
 437        /// is then auto-indented to column `b`, then every other line of
 438        /// the insertion will be auto-indented to column `b - a`
 439        original_indent_columns: Vec<Option<u32>>,
 440    },
 441}
 442
 443#[derive(Clone)]
 444struct AutoindentRequest {
 445    before_edit: BufferSnapshot,
 446    entries: Vec<AutoindentRequestEntry>,
 447    is_block_mode: bool,
 448    ignore_empty_lines: bool,
 449}
 450
 451#[derive(Debug, Clone)]
 452struct AutoindentRequestEntry {
 453    /// A range of the buffer whose indentation should be adjusted.
 454    range: Range<Anchor>,
 455    /// Whether or not these lines should be considered brand new, for the
 456    /// purpose of auto-indent. When text is not new, its indentation will
 457    /// only be adjusted if the suggested indentation level has *changed*
 458    /// since the edit was made.
 459    first_line_is_new: bool,
 460    indent_size: IndentSize,
 461    original_indent_column: Option<u32>,
 462}
 463
 464#[derive(Debug)]
 465struct IndentSuggestion {
 466    basis_row: u32,
 467    delta: Ordering,
 468    within_error: bool,
 469}
 470
 471struct BufferChunkHighlights<'a> {
 472    captures: SyntaxMapCaptures<'a>,
 473    next_capture: Option<SyntaxMapCapture<'a>>,
 474    stack: Vec<(usize, HighlightId)>,
 475    highlight_maps: Vec<HighlightMap>,
 476}
 477
 478/// An iterator that yields chunks of a buffer's text, along with their
 479/// syntax highlights and diagnostic status.
 480pub struct BufferChunks<'a> {
 481    buffer_snapshot: Option<&'a BufferSnapshot>,
 482    range: Range<usize>,
 483    chunks: text::Chunks<'a>,
 484    diagnostic_endpoints: Option<Peekable<vec::IntoIter<DiagnosticEndpoint>>>,
 485    error_depth: usize,
 486    warning_depth: usize,
 487    information_depth: usize,
 488    hint_depth: usize,
 489    unnecessary_depth: usize,
 490    underline: bool,
 491    highlights: Option<BufferChunkHighlights<'a>>,
 492}
 493
 494/// A chunk of a buffer's text, along with its syntax highlight and
 495/// diagnostic status.
 496#[derive(Clone, Debug, Default)]
 497pub struct Chunk<'a> {
 498    /// The text of the chunk.
 499    pub text: &'a str,
 500    /// The syntax highlighting style of the chunk.
 501    pub syntax_highlight_id: Option<HighlightId>,
 502    /// The highlight style that has been applied to this chunk in
 503    /// the editor.
 504    pub highlight_style: Option<HighlightStyle>,
 505    /// The severity of diagnostic associated with this chunk, if any.
 506    pub diagnostic_severity: Option<DiagnosticSeverity>,
 507    /// Whether this chunk of text is marked as unnecessary.
 508    pub is_unnecessary: bool,
 509    /// Whether this chunk of text was originally a tab character.
 510    pub is_tab: bool,
 511    /// A bitset of which characters are tabs in this string.
 512    pub tabs: u128,
 513    /// Bitmap of character indices in this chunk
 514    pub chars: u128,
 515    /// Whether this chunk of text was originally a tab character.
 516    pub is_inlay: bool,
 517    /// Whether to underline the corresponding text range in the editor.
 518    pub underline: bool,
 519}
 520
 521/// A set of edits to a given version of a buffer, computed asynchronously.
 522#[derive(Debug)]
 523pub struct Diff {
 524    pub base_version: clock::Global,
 525    pub line_ending: LineEnding,
 526    pub edits: Vec<(Range<usize>, Arc<str>)>,
 527}
 528
 529#[derive(Debug, Clone, Copy)]
 530pub(crate) struct DiagnosticEndpoint {
 531    offset: usize,
 532    is_start: bool,
 533    underline: bool,
 534    severity: DiagnosticSeverity,
 535    is_unnecessary: bool,
 536}
 537
 538/// A class of characters, used for characterizing a run of text.
 539#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 540pub enum CharKind {
 541    /// Whitespace.
 542    Whitespace,
 543    /// Punctuation.
 544    Punctuation,
 545    /// Word.
 546    Word,
 547}
 548
 549/// Context for character classification within a specific scope.
 550#[derive(Copy, Clone, Eq, PartialEq, Debug)]
 551pub enum CharScopeContext {
 552    /// Character classification for completion queries.
 553    ///
 554    /// This context treats certain characters as word constituents that would
 555    /// normally be considered punctuation, such as '-' in Tailwind classes
 556    /// ("bg-yellow-100") or '.' in import paths ("foo.ts").
 557    Completion,
 558    /// Character classification for linked edits.
 559    ///
 560    /// This context handles characters that should be treated as part of
 561    /// identifiers during linked editing operations, such as '.' in JSX
 562    /// component names like `<Animated.View>`.
 563    LinkedEdit,
 564}
 565
 566/// A runnable is a set of data about a region that could be resolved into a task
 567pub struct Runnable {
 568    pub tags: SmallVec<[RunnableTag; 1]>,
 569    pub language: Arc<Language>,
 570    pub buffer: BufferId,
 571}
 572
 573#[derive(Default, Clone, Debug)]
 574pub struct HighlightedText {
 575    pub text: SharedString,
 576    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 577}
 578
 579#[derive(Default, Debug)]
 580struct HighlightedTextBuilder {
 581    pub text: String,
 582    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 583}
 584
 585impl HighlightedText {
 586    pub fn from_buffer_range<T: ToOffset>(
 587        range: Range<T>,
 588        snapshot: &text::BufferSnapshot,
 589        syntax_snapshot: &SyntaxSnapshot,
 590        override_style: Option<HighlightStyle>,
 591        syntax_theme: &SyntaxTheme,
 592    ) -> Self {
 593        let mut highlighted_text = HighlightedTextBuilder::default();
 594        highlighted_text.add_text_from_buffer_range(
 595            range,
 596            snapshot,
 597            syntax_snapshot,
 598            override_style,
 599            syntax_theme,
 600        );
 601        highlighted_text.build()
 602    }
 603
 604    pub fn to_styled_text(&self, default_style: &TextStyle) -> StyledText {
 605        gpui::StyledText::new(self.text.clone())
 606            .with_default_highlights(default_style, self.highlights.iter().cloned())
 607    }
 608
 609    /// Returns the first line without leading whitespace unless highlighted
 610    /// and a boolean indicating if there are more lines after
 611    pub fn first_line_preview(self) -> (Self, bool) {
 612        let newline_ix = self.text.find('\n').unwrap_or(self.text.len());
 613        let first_line = &self.text[..newline_ix];
 614
 615        // Trim leading whitespace, unless an edit starts prior to it.
 616        let mut preview_start_ix = first_line.len() - first_line.trim_start().len();
 617        if let Some((first_highlight_range, _)) = self.highlights.first() {
 618            preview_start_ix = preview_start_ix.min(first_highlight_range.start);
 619        }
 620
 621        let preview_text = &first_line[preview_start_ix..];
 622        let preview_highlights = self
 623            .highlights
 624            .into_iter()
 625            .take_while(|(range, _)| range.start < newline_ix)
 626            .filter_map(|(mut range, highlight)| {
 627                range.start = range.start.saturating_sub(preview_start_ix);
 628                range.end = range.end.saturating_sub(preview_start_ix).min(newline_ix);
 629                if range.is_empty() {
 630                    None
 631                } else {
 632                    Some((range, highlight))
 633                }
 634            });
 635
 636        let preview = Self {
 637            text: SharedString::new(preview_text),
 638            highlights: preview_highlights.collect(),
 639        };
 640
 641        (preview, self.text.len() > newline_ix)
 642    }
 643}
 644
 645impl HighlightedTextBuilder {
 646    pub fn build(self) -> HighlightedText {
 647        HighlightedText {
 648            text: self.text.into(),
 649            highlights: self.highlights,
 650        }
 651    }
 652
 653    pub fn add_text_from_buffer_range<T: ToOffset>(
 654        &mut self,
 655        range: Range<T>,
 656        snapshot: &text::BufferSnapshot,
 657        syntax_snapshot: &SyntaxSnapshot,
 658        override_style: Option<HighlightStyle>,
 659        syntax_theme: &SyntaxTheme,
 660    ) {
 661        let range = range.to_offset(snapshot);
 662        for chunk in Self::highlighted_chunks(range, snapshot, syntax_snapshot) {
 663            let start = self.text.len();
 664            self.text.push_str(chunk.text);
 665            let end = self.text.len();
 666
 667            if let Some(highlight_style) = chunk
 668                .syntax_highlight_id
 669                .and_then(|id| id.style(syntax_theme))
 670            {
 671                let highlight_style = override_style.map_or(highlight_style, |override_style| {
 672                    highlight_style.highlight(override_style)
 673                });
 674                self.highlights.push((start..end, highlight_style));
 675            } else if let Some(override_style) = override_style {
 676                self.highlights.push((start..end, override_style));
 677            }
 678        }
 679    }
 680
 681    fn highlighted_chunks<'a>(
 682        range: Range<usize>,
 683        snapshot: &'a text::BufferSnapshot,
 684        syntax_snapshot: &'a SyntaxSnapshot,
 685    ) -> BufferChunks<'a> {
 686        let captures = syntax_snapshot.captures(range.clone(), snapshot, |grammar| {
 687            grammar
 688                .highlights_config
 689                .as_ref()
 690                .map(|config| &config.query)
 691        });
 692
 693        let highlight_maps = captures
 694            .grammars()
 695            .iter()
 696            .map(|grammar| grammar.highlight_map())
 697            .collect();
 698
 699        BufferChunks::new(
 700            snapshot.as_rope(),
 701            range,
 702            Some((captures, highlight_maps)),
 703            false,
 704            None,
 705        )
 706    }
 707}
 708
 709#[derive(Clone)]
 710pub struct EditPreview {
 711    old_snapshot: text::BufferSnapshot,
 712    applied_edits_snapshot: text::BufferSnapshot,
 713    syntax_snapshot: SyntaxSnapshot,
 714}
 715
 716impl EditPreview {
 717    pub fn highlight_edits(
 718        &self,
 719        current_snapshot: &BufferSnapshot,
 720        edits: &[(Range<Anchor>, String)],
 721        include_deletions: bool,
 722        cx: &App,
 723    ) -> HighlightedText {
 724        let Some(visible_range_in_preview_snapshot) = self.compute_visible_range(edits) else {
 725            return HighlightedText::default();
 726        };
 727
 728        let mut highlighted_text = HighlightedTextBuilder::default();
 729
 730        let mut offset_in_preview_snapshot = visible_range_in_preview_snapshot.start;
 731
 732        let insertion_highlight_style = HighlightStyle {
 733            background_color: Some(cx.theme().status().created_background),
 734            ..Default::default()
 735        };
 736        let deletion_highlight_style = HighlightStyle {
 737            background_color: Some(cx.theme().status().deleted_background),
 738            ..Default::default()
 739        };
 740        let syntax_theme = cx.theme().syntax();
 741
 742        for (range, edit_text) in edits {
 743            let edit_new_end_in_preview_snapshot = range
 744                .end
 745                .bias_right(&self.old_snapshot)
 746                .to_offset(&self.applied_edits_snapshot);
 747            let edit_start_in_preview_snapshot = edit_new_end_in_preview_snapshot - edit_text.len();
 748
 749            let unchanged_range_in_preview_snapshot =
 750                offset_in_preview_snapshot..edit_start_in_preview_snapshot;
 751            if !unchanged_range_in_preview_snapshot.is_empty() {
 752                highlighted_text.add_text_from_buffer_range(
 753                    unchanged_range_in_preview_snapshot,
 754                    &self.applied_edits_snapshot,
 755                    &self.syntax_snapshot,
 756                    None,
 757                    syntax_theme,
 758                );
 759            }
 760
 761            let range_in_current_snapshot = range.to_offset(current_snapshot);
 762            if include_deletions && !range_in_current_snapshot.is_empty() {
 763                highlighted_text.add_text_from_buffer_range(
 764                    range_in_current_snapshot,
 765                    &current_snapshot.text,
 766                    &current_snapshot.syntax,
 767                    Some(deletion_highlight_style),
 768                    syntax_theme,
 769                );
 770            }
 771
 772            if !edit_text.is_empty() {
 773                highlighted_text.add_text_from_buffer_range(
 774                    edit_start_in_preview_snapshot..edit_new_end_in_preview_snapshot,
 775                    &self.applied_edits_snapshot,
 776                    &self.syntax_snapshot,
 777                    Some(insertion_highlight_style),
 778                    syntax_theme,
 779                );
 780            }
 781
 782            offset_in_preview_snapshot = edit_new_end_in_preview_snapshot;
 783        }
 784
 785        highlighted_text.add_text_from_buffer_range(
 786            offset_in_preview_snapshot..visible_range_in_preview_snapshot.end,
 787            &self.applied_edits_snapshot,
 788            &self.syntax_snapshot,
 789            None,
 790            syntax_theme,
 791        );
 792
 793        highlighted_text.build()
 794    }
 795
 796    fn compute_visible_range(&self, edits: &[(Range<Anchor>, String)]) -> Option<Range<usize>> {
 797        let (first, _) = edits.first()?;
 798        let (last, _) = edits.last()?;
 799
 800        let start = first
 801            .start
 802            .bias_left(&self.old_snapshot)
 803            .to_point(&self.applied_edits_snapshot);
 804        let end = last
 805            .end
 806            .bias_right(&self.old_snapshot)
 807            .to_point(&self.applied_edits_snapshot);
 808
 809        // Ensure that the first line of the first edit and the last line of the last edit are always fully visible
 810        let range = Point::new(start.row, 0)
 811            ..Point::new(end.row, self.applied_edits_snapshot.line_len(end.row));
 812
 813        Some(range.to_offset(&self.applied_edits_snapshot))
 814    }
 815}
 816
 817#[derive(Clone, Debug, PartialEq, Eq)]
 818pub struct BracketMatch {
 819    pub open_range: Range<usize>,
 820    pub close_range: Range<usize>,
 821    pub newline_only: bool,
 822}
 823
 824impl Buffer {
 825    /// Create a new buffer with the given base text.
 826    pub fn local<T: Into<String>>(base_text: T, cx: &Context<Self>) -> Self {
 827        Self::build(
 828            TextBuffer::new(0, cx.entity_id().as_non_zero_u64().into(), base_text.into()),
 829            None,
 830            Capability::ReadWrite,
 831        )
 832    }
 833
 834    /// Create a new buffer with the given base text that has proper line endings and other normalization applied.
 835    pub fn local_normalized(
 836        base_text_normalized: Rope,
 837        line_ending: LineEnding,
 838        cx: &Context<Self>,
 839    ) -> Self {
 840        Self::build(
 841            TextBuffer::new_normalized(
 842                0,
 843                cx.entity_id().as_non_zero_u64().into(),
 844                line_ending,
 845                base_text_normalized,
 846            ),
 847            None,
 848            Capability::ReadWrite,
 849        )
 850    }
 851
 852    /// Create a new buffer that is a replica of a remote buffer.
 853    pub fn remote(
 854        remote_id: BufferId,
 855        replica_id: ReplicaId,
 856        capability: Capability,
 857        base_text: impl Into<String>,
 858    ) -> Self {
 859        Self::build(
 860            TextBuffer::new(replica_id, remote_id, base_text.into()),
 861            None,
 862            capability,
 863        )
 864    }
 865
 866    /// Create a new buffer that is a replica of a remote buffer, populating its
 867    /// state from the given protobuf message.
 868    pub fn from_proto(
 869        replica_id: ReplicaId,
 870        capability: Capability,
 871        message: proto::BufferState,
 872        file: Option<Arc<dyn File>>,
 873    ) -> Result<Self> {
 874        let buffer_id = BufferId::new(message.id).context("Could not deserialize buffer_id")?;
 875        let buffer = TextBuffer::new(replica_id, buffer_id, message.base_text);
 876        let mut this = Self::build(buffer, file, capability);
 877        this.text.set_line_ending(proto::deserialize_line_ending(
 878            rpc::proto::LineEnding::from_i32(message.line_ending).context("missing line_ending")?,
 879        ));
 880        this.saved_version = proto::deserialize_version(&message.saved_version);
 881        this.saved_mtime = message.saved_mtime.map(|time| time.into());
 882        Ok(this)
 883    }
 884
 885    /// Serialize the buffer's state to a protobuf message.
 886    pub fn to_proto(&self, cx: &App) -> proto::BufferState {
 887        proto::BufferState {
 888            id: self.remote_id().into(),
 889            file: self.file.as_ref().map(|f| f.to_proto(cx)),
 890            base_text: self.base_text().to_string(),
 891            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 892            saved_version: proto::serialize_version(&self.saved_version),
 893            saved_mtime: self.saved_mtime.map(|time| time.into()),
 894        }
 895    }
 896
 897    /// Serialize as protobufs all of the changes to the buffer since the given version.
 898    pub fn serialize_ops(
 899        &self,
 900        since: Option<clock::Global>,
 901        cx: &App,
 902    ) -> Task<Vec<proto::Operation>> {
 903        let mut operations = Vec::new();
 904        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 905
 906        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 907            proto::serialize_operation(&Operation::UpdateSelections {
 908                selections: set.selections.clone(),
 909                lamport_timestamp: set.lamport_timestamp,
 910                line_mode: set.line_mode,
 911                cursor_shape: set.cursor_shape,
 912            })
 913        }));
 914
 915        for (server_id, diagnostics) in &self.diagnostics {
 916            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 917                lamport_timestamp: self.diagnostics_timestamp,
 918                server_id: *server_id,
 919                diagnostics: diagnostics.iter().cloned().collect(),
 920            }));
 921        }
 922
 923        for (server_id, completions) in &self.completion_triggers_per_language_server {
 924            operations.push(proto::serialize_operation(
 925                &Operation::UpdateCompletionTriggers {
 926                    triggers: completions.iter().cloned().collect(),
 927                    lamport_timestamp: self.completion_triggers_timestamp,
 928                    server_id: *server_id,
 929                },
 930            ));
 931        }
 932
 933        let text_operations = self.text.operations().clone();
 934        cx.background_spawn(async move {
 935            let since = since.unwrap_or_default();
 936            operations.extend(
 937                text_operations
 938                    .iter()
 939                    .filter(|(_, op)| !since.observed(op.timestamp()))
 940                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 941            );
 942            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 943            operations
 944        })
 945    }
 946
 947    /// Assign a language to the buffer, returning the buffer.
 948    pub fn with_language(mut self, language: Arc<Language>, cx: &mut Context<Self>) -> Self {
 949        self.set_language(Some(language), cx);
 950        self
 951    }
 952
 953    /// Returns the [`Capability`] of this buffer.
 954    pub fn capability(&self) -> Capability {
 955        self.capability
 956    }
 957
 958    /// Whether this buffer can only be read.
 959    pub fn read_only(&self) -> bool {
 960        self.capability == Capability::ReadOnly
 961    }
 962
 963    /// Builds a [`Buffer`] with the given underlying [`TextBuffer`], diff base, [`File`] and [`Capability`].
 964    pub fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>, capability: Capability) -> Self {
 965        let saved_mtime = file.as_ref().and_then(|file| file.disk_state().mtime());
 966        let snapshot = buffer.snapshot();
 967        let syntax_map = Mutex::new(SyntaxMap::new(&snapshot));
 968        Self {
 969            saved_mtime,
 970            saved_version: buffer.version(),
 971            preview_version: buffer.version(),
 972            reload_task: None,
 973            transaction_depth: 0,
 974            was_dirty_before_starting_transaction: None,
 975            has_unsaved_edits: Cell::new((buffer.version(), false)),
 976            text: buffer,
 977            branch_state: None,
 978            file,
 979            capability,
 980            syntax_map,
 981            reparse: None,
 982            non_text_state_update_count: 0,
 983            sync_parse_timeout: Duration::from_millis(1),
 984            parse_status: watch::channel(ParseStatus::Idle),
 985            autoindent_requests: Default::default(),
 986            wait_for_autoindent_txs: Default::default(),
 987            pending_autoindent: Default::default(),
 988            language: None,
 989            remote_selections: Default::default(),
 990            diagnostics: Default::default(),
 991            diagnostics_timestamp: Default::default(),
 992            completion_triggers: Default::default(),
 993            completion_triggers_per_language_server: Default::default(),
 994            completion_triggers_timestamp: Default::default(),
 995            deferred_ops: OperationQueue::new(),
 996            has_conflict: false,
 997            change_bits: Default::default(),
 998            _subscriptions: Vec::new(),
 999        }
1000    }
1001
1002    pub fn build_snapshot(
1003        text: Rope,
1004        language: Option<Arc<Language>>,
1005        language_registry: Option<Arc<LanguageRegistry>>,
1006        cx: &mut App,
1007    ) -> impl Future<Output = BufferSnapshot> + use<> {
1008        let entity_id = cx.reserve_entity::<Self>().entity_id();
1009        let buffer_id = entity_id.as_non_zero_u64().into();
1010        async move {
1011            let text =
1012                TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
1013            let mut syntax = SyntaxMap::new(&text).snapshot();
1014            if let Some(language) = language.clone() {
1015                let language_registry = language_registry.clone();
1016                syntax.reparse(&text, language_registry, language);
1017            }
1018            BufferSnapshot {
1019                text,
1020                syntax,
1021                file: None,
1022                diagnostics: Default::default(),
1023                remote_selections: Default::default(),
1024                language,
1025                non_text_state_update_count: 0,
1026            }
1027        }
1028    }
1029
1030    pub fn build_empty_snapshot(cx: &mut App) -> BufferSnapshot {
1031        let entity_id = cx.reserve_entity::<Self>().entity_id();
1032        let buffer_id = entity_id.as_non_zero_u64().into();
1033        let text =
1034            TextBuffer::new_normalized(0, buffer_id, Default::default(), Rope::new()).snapshot();
1035        let syntax = SyntaxMap::new(&text).snapshot();
1036        BufferSnapshot {
1037            text,
1038            syntax,
1039            file: None,
1040            diagnostics: Default::default(),
1041            remote_selections: Default::default(),
1042            language: None,
1043            non_text_state_update_count: 0,
1044        }
1045    }
1046
1047    #[cfg(any(test, feature = "test-support"))]
1048    pub fn build_snapshot_sync(
1049        text: Rope,
1050        language: Option<Arc<Language>>,
1051        language_registry: Option<Arc<LanguageRegistry>>,
1052        cx: &mut App,
1053    ) -> BufferSnapshot {
1054        let entity_id = cx.reserve_entity::<Self>().entity_id();
1055        let buffer_id = entity_id.as_non_zero_u64().into();
1056        let text = TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
1057        let mut syntax = SyntaxMap::new(&text).snapshot();
1058        if let Some(language) = language.clone() {
1059            syntax.reparse(&text, language_registry, language);
1060        }
1061        BufferSnapshot {
1062            text,
1063            syntax,
1064            file: None,
1065            diagnostics: Default::default(),
1066            remote_selections: Default::default(),
1067            language,
1068            non_text_state_update_count: 0,
1069        }
1070    }
1071
1072    /// Retrieve a snapshot of the buffer's current state. This is computationally
1073    /// cheap, and allows reading from the buffer on a background thread.
1074    pub fn snapshot(&self) -> BufferSnapshot {
1075        let text = self.text.snapshot();
1076        let mut syntax_map = self.syntax_map.lock();
1077        syntax_map.interpolate(&text);
1078        let syntax = syntax_map.snapshot();
1079
1080        BufferSnapshot {
1081            text,
1082            syntax,
1083            file: self.file.clone(),
1084            remote_selections: self.remote_selections.clone(),
1085            diagnostics: self.diagnostics.clone(),
1086            language: self.language.clone(),
1087            non_text_state_update_count: self.non_text_state_update_count,
1088        }
1089    }
1090
1091    pub fn branch(&mut self, cx: &mut Context<Self>) -> Entity<Self> {
1092        let this = cx.entity();
1093        cx.new(|cx| {
1094            let mut branch = Self {
1095                branch_state: Some(BufferBranchState {
1096                    base_buffer: this.clone(),
1097                    merged_operations: Default::default(),
1098                }),
1099                language: self.language.clone(),
1100                has_conflict: self.has_conflict,
1101                has_unsaved_edits: Cell::new(self.has_unsaved_edits.get_mut().clone()),
1102                _subscriptions: vec![cx.subscribe(&this, Self::on_base_buffer_event)],
1103                ..Self::build(self.text.branch(), self.file.clone(), self.capability())
1104            };
1105            if let Some(language_registry) = self.language_registry() {
1106                branch.set_language_registry(language_registry);
1107            }
1108
1109            // Reparse the branch buffer so that we get syntax highlighting immediately.
1110            branch.reparse(cx);
1111
1112            branch
1113        })
1114    }
1115
1116    pub fn preview_edits(
1117        &self,
1118        edits: Arc<[(Range<Anchor>, String)]>,
1119        cx: &App,
1120    ) -> Task<EditPreview> {
1121        let registry = self.language_registry();
1122        let language = self.language().cloned();
1123        let old_snapshot = self.text.snapshot();
1124        let mut branch_buffer = self.text.branch();
1125        let mut syntax_snapshot = self.syntax_map.lock().snapshot();
1126        cx.background_spawn(async move {
1127            if !edits.is_empty() {
1128                if let Some(language) = language.clone() {
1129                    syntax_snapshot.reparse(&old_snapshot, registry.clone(), language);
1130                }
1131
1132                branch_buffer.edit(edits.iter().cloned());
1133                let snapshot = branch_buffer.snapshot();
1134                syntax_snapshot.interpolate(&snapshot);
1135
1136                if let Some(language) = language {
1137                    syntax_snapshot.reparse(&snapshot, registry, language);
1138                }
1139            }
1140            EditPreview {
1141                old_snapshot,
1142                applied_edits_snapshot: branch_buffer.snapshot(),
1143                syntax_snapshot,
1144            }
1145        })
1146    }
1147
1148    /// Applies all of the changes in this buffer that intersect any of the
1149    /// given `ranges` to its base buffer.
1150    ///
1151    /// If `ranges` is empty, then all changes will be applied. This buffer must
1152    /// be a branch buffer to call this method.
1153    pub fn merge_into_base(&mut self, ranges: Vec<Range<usize>>, cx: &mut Context<Self>) {
1154        let Some(base_buffer) = self.base_buffer() else {
1155            debug_panic!("not a branch buffer");
1156            return;
1157        };
1158
1159        let mut ranges = if ranges.is_empty() {
1160            &[0..usize::MAX]
1161        } else {
1162            ranges.as_slice()
1163        }
1164        .iter()
1165        .peekable();
1166
1167        let mut edits = Vec::new();
1168        for edit in self.edits_since::<usize>(&base_buffer.read(cx).version()) {
1169            let mut is_included = false;
1170            while let Some(range) = ranges.peek() {
1171                if range.end < edit.new.start {
1172                    ranges.next().unwrap();
1173                } else {
1174                    if range.start <= edit.new.end {
1175                        is_included = true;
1176                    }
1177                    break;
1178                }
1179            }
1180
1181            if is_included {
1182                edits.push((
1183                    edit.old.clone(),
1184                    self.text_for_range(edit.new.clone()).collect::<String>(),
1185                ));
1186            }
1187        }
1188
1189        let operation = base_buffer.update(cx, |base_buffer, cx| {
1190            // cx.emit(BufferEvent::DiffBaseChanged);
1191            base_buffer.edit(edits, None, cx)
1192        });
1193
1194        if let Some(operation) = operation
1195            && let Some(BufferBranchState {
1196                merged_operations, ..
1197            }) = &mut self.branch_state
1198        {
1199            merged_operations.push(operation);
1200        }
1201    }
1202
1203    fn on_base_buffer_event(
1204        &mut self,
1205        _: Entity<Buffer>,
1206        event: &BufferEvent,
1207        cx: &mut Context<Self>,
1208    ) {
1209        let BufferEvent::Operation { operation, .. } = event else {
1210            return;
1211        };
1212        let Some(BufferBranchState {
1213            merged_operations, ..
1214        }) = &mut self.branch_state
1215        else {
1216            return;
1217        };
1218
1219        let mut operation_to_undo = None;
1220        if let Operation::Buffer(text::Operation::Edit(operation)) = &operation
1221            && let Ok(ix) = merged_operations.binary_search(&operation.timestamp)
1222        {
1223            merged_operations.remove(ix);
1224            operation_to_undo = Some(operation.timestamp);
1225        }
1226
1227        self.apply_ops([operation.clone()], cx);
1228
1229        if let Some(timestamp) = operation_to_undo {
1230            let counts = [(timestamp, u32::MAX)].into_iter().collect();
1231            self.undo_operations(counts, cx);
1232        }
1233    }
1234
1235    #[cfg(test)]
1236    pub(crate) fn as_text_snapshot(&self) -> &text::BufferSnapshot {
1237        &self.text
1238    }
1239
1240    /// Retrieve a snapshot of the buffer's raw text, without any
1241    /// language-related state like the syntax tree or diagnostics.
1242    pub fn text_snapshot(&self) -> text::BufferSnapshot {
1243        self.text.snapshot()
1244    }
1245
1246    /// The file associated with the buffer, if any.
1247    pub fn file(&self) -> Option<&Arc<dyn File>> {
1248        self.file.as_ref()
1249    }
1250
1251    /// The version of the buffer that was last saved or reloaded from disk.
1252    pub fn saved_version(&self) -> &clock::Global {
1253        &self.saved_version
1254    }
1255
1256    /// The mtime of the buffer's file when the buffer was last saved or reloaded from disk.
1257    pub fn saved_mtime(&self) -> Option<MTime> {
1258        self.saved_mtime
1259    }
1260
1261    /// Assign a language to the buffer.
1262    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut Context<Self>) {
1263        self.non_text_state_update_count += 1;
1264        self.syntax_map.lock().clear(&self.text);
1265        self.language = language;
1266        self.was_changed();
1267        self.reparse(cx);
1268        cx.emit(BufferEvent::LanguageChanged);
1269    }
1270
1271    /// Assign a language registry to the buffer. This allows the buffer to retrieve
1272    /// other languages if parts of the buffer are written in different languages.
1273    pub fn set_language_registry(&self, language_registry: Arc<LanguageRegistry>) {
1274        self.syntax_map
1275            .lock()
1276            .set_language_registry(language_registry);
1277    }
1278
1279    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
1280        self.syntax_map.lock().language_registry()
1281    }
1282
1283    /// Assign the line ending type to the buffer.
1284    pub fn set_line_ending(&mut self, line_ending: LineEnding, cx: &mut Context<Self>) {
1285        self.text.set_line_ending(line_ending);
1286
1287        let lamport_timestamp = self.text.lamport_clock.tick();
1288        self.send_operation(
1289            Operation::UpdateLineEnding {
1290                line_ending,
1291                lamport_timestamp,
1292            },
1293            true,
1294            cx,
1295        );
1296    }
1297
1298    /// Assign the buffer a new [`Capability`].
1299    pub fn set_capability(&mut self, capability: Capability, cx: &mut Context<Self>) {
1300        if self.capability != capability {
1301            self.capability = capability;
1302            cx.emit(BufferEvent::CapabilityChanged)
1303        }
1304    }
1305
1306    /// This method is called to signal that the buffer has been saved.
1307    pub fn did_save(
1308        &mut self,
1309        version: clock::Global,
1310        mtime: Option<MTime>,
1311        cx: &mut Context<Self>,
1312    ) {
1313        self.saved_version = version;
1314        self.has_unsaved_edits
1315            .set((self.saved_version().clone(), false));
1316        self.has_conflict = false;
1317        self.saved_mtime = mtime;
1318        self.was_changed();
1319        cx.emit(BufferEvent::Saved);
1320        cx.notify();
1321    }
1322
1323    /// Reloads the contents of the buffer from disk.
1324    pub fn reload(&mut self, cx: &Context<Self>) -> oneshot::Receiver<Option<Transaction>> {
1325        let (tx, rx) = futures::channel::oneshot::channel();
1326        let prev_version = self.text.version();
1327        self.reload_task = Some(cx.spawn(async move |this, cx| {
1328            let Some((new_mtime, new_text)) = this.update(cx, |this, cx| {
1329                let file = this.file.as_ref()?.as_local()?;
1330
1331                Some((file.disk_state().mtime(), file.load(cx)))
1332            })?
1333            else {
1334                return Ok(());
1335            };
1336
1337            let new_text = new_text.await?;
1338            let diff = this
1339                .update(cx, |this, cx| this.diff(new_text.clone(), cx))?
1340                .await;
1341            this.update(cx, |this, cx| {
1342                if this.version() == diff.base_version {
1343                    this.finalize_last_transaction();
1344                    this.apply_diff(diff, cx);
1345                    tx.send(this.finalize_last_transaction().cloned()).ok();
1346                    this.has_conflict = false;
1347                    this.did_reload(this.version(), this.line_ending(), new_mtime, cx);
1348                } else {
1349                    if !diff.edits.is_empty()
1350                        || this
1351                            .edits_since::<usize>(&diff.base_version)
1352                            .next()
1353                            .is_some()
1354                    {
1355                        this.has_conflict = true;
1356                    }
1357
1358                    this.did_reload(prev_version, this.line_ending(), this.saved_mtime, cx);
1359                }
1360
1361                this.reload_task.take();
1362            })
1363        }));
1364        rx
1365    }
1366
1367    /// This method is called to signal that the buffer has been reloaded.
1368    pub fn did_reload(
1369        &mut self,
1370        version: clock::Global,
1371        line_ending: LineEnding,
1372        mtime: Option<MTime>,
1373        cx: &mut Context<Self>,
1374    ) {
1375        self.saved_version = version;
1376        self.has_unsaved_edits
1377            .set((self.saved_version.clone(), false));
1378        self.text.set_line_ending(line_ending);
1379        self.saved_mtime = mtime;
1380        cx.emit(BufferEvent::Reloaded);
1381        cx.notify();
1382    }
1383
1384    /// Updates the [`File`] backing this buffer. This should be called when
1385    /// the file has changed or has been deleted.
1386    pub fn file_updated(&mut self, new_file: Arc<dyn File>, cx: &mut Context<Self>) {
1387        let was_dirty = self.is_dirty();
1388        let mut file_changed = false;
1389
1390        if let Some(old_file) = self.file.as_ref() {
1391            if new_file.path() != old_file.path() {
1392                file_changed = true;
1393            }
1394
1395            let old_state = old_file.disk_state();
1396            let new_state = new_file.disk_state();
1397            if old_state != new_state {
1398                file_changed = true;
1399                if !was_dirty && matches!(new_state, DiskState::Present { .. }) {
1400                    cx.emit(BufferEvent::ReloadNeeded)
1401                }
1402            }
1403        } else {
1404            file_changed = true;
1405        };
1406
1407        self.file = Some(new_file);
1408        if file_changed {
1409            self.was_changed();
1410            self.non_text_state_update_count += 1;
1411            if was_dirty != self.is_dirty() {
1412                cx.emit(BufferEvent::DirtyChanged);
1413            }
1414            cx.emit(BufferEvent::FileHandleChanged);
1415            cx.notify();
1416        }
1417    }
1418
1419    pub fn base_buffer(&self) -> Option<Entity<Self>> {
1420        Some(self.branch_state.as_ref()?.base_buffer.clone())
1421    }
1422
1423    /// Returns the primary [`Language`] assigned to this [`Buffer`].
1424    pub fn language(&self) -> Option<&Arc<Language>> {
1425        self.language.as_ref()
1426    }
1427
1428    /// Returns the [`Language`] at the given location.
1429    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
1430        let offset = position.to_offset(self);
1431        let mut is_first = true;
1432        let start_anchor = self.anchor_before(offset);
1433        let end_anchor = self.anchor_after(offset);
1434        self.syntax_map
1435            .lock()
1436            .layers_for_range(offset..offset, &self.text, false)
1437            .filter(|layer| {
1438                if is_first {
1439                    is_first = false;
1440                    return true;
1441                }
1442
1443                layer
1444                    .included_sub_ranges
1445                    .map(|sub_ranges| {
1446                        sub_ranges.iter().any(|sub_range| {
1447                            let is_before_start = sub_range.end.cmp(&start_anchor, self).is_lt();
1448                            let is_after_end = sub_range.start.cmp(&end_anchor, self).is_gt();
1449                            !is_before_start && !is_after_end
1450                        })
1451                    })
1452                    .unwrap_or(true)
1453            })
1454            .last()
1455            .map(|info| info.language.clone())
1456            .or_else(|| self.language.clone())
1457    }
1458
1459    /// Returns each [`Language`] for the active syntax layers at the given location.
1460    pub fn languages_at<D: ToOffset>(&self, position: D) -> Vec<Arc<Language>> {
1461        let offset = position.to_offset(self);
1462        let mut languages: Vec<Arc<Language>> = self
1463            .syntax_map
1464            .lock()
1465            .layers_for_range(offset..offset, &self.text, false)
1466            .map(|info| info.language.clone())
1467            .collect();
1468
1469        if languages.is_empty()
1470            && let Some(buffer_language) = self.language()
1471        {
1472            languages.push(buffer_language.clone());
1473        }
1474
1475        languages
1476    }
1477
1478    /// An integer version number that accounts for all updates besides
1479    /// the buffer's text itself (which is versioned via a version vector).
1480    pub fn non_text_state_update_count(&self) -> usize {
1481        self.non_text_state_update_count
1482    }
1483
1484    /// Whether the buffer is being parsed in the background.
1485    #[cfg(any(test, feature = "test-support"))]
1486    pub fn is_parsing(&self) -> bool {
1487        self.reparse.is_some()
1488    }
1489
1490    /// Indicates whether the buffer contains any regions that may be
1491    /// written in a language that hasn't been loaded yet.
1492    pub fn contains_unknown_injections(&self) -> bool {
1493        self.syntax_map.lock().contains_unknown_injections()
1494    }
1495
1496    #[cfg(any(test, feature = "test-support"))]
1497    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
1498        self.sync_parse_timeout = timeout;
1499    }
1500
1501    /// Called after an edit to synchronize the buffer's main parse tree with
1502    /// the buffer's new underlying state.
1503    ///
1504    /// Locks the syntax map and interpolates the edits since the last reparse
1505    /// into the foreground syntax tree.
1506    ///
1507    /// Then takes a stable snapshot of the syntax map before unlocking it.
1508    /// The snapshot with the interpolated edits is sent to a background thread,
1509    /// where we ask Tree-sitter to perform an incremental parse.
1510    ///
1511    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
1512    /// waiting on the parse to complete. As soon as it completes, we proceed
1513    /// synchronously, unless a 1ms timeout elapses.
1514    ///
1515    /// If we time out waiting on the parse, we spawn a second task waiting
1516    /// until the parse does complete and return with the interpolated tree still
1517    /// in the foreground. When the background parse completes, call back into
1518    /// the main thread and assign the foreground parse state.
1519    ///
1520    /// If the buffer or grammar changed since the start of the background parse,
1521    /// initiate an additional reparse recursively. To avoid concurrent parses
1522    /// for the same buffer, we only initiate a new parse if we are not already
1523    /// parsing in the background.
1524    pub fn reparse(&mut self, cx: &mut Context<Self>) {
1525        if self.reparse.is_some() {
1526            return;
1527        }
1528        let language = if let Some(language) = self.language.clone() {
1529            language
1530        } else {
1531            return;
1532        };
1533
1534        let text = self.text_snapshot();
1535        let parsed_version = self.version();
1536
1537        let mut syntax_map = self.syntax_map.lock();
1538        syntax_map.interpolate(&text);
1539        let language_registry = syntax_map.language_registry();
1540        let mut syntax_snapshot = syntax_map.snapshot();
1541        drop(syntax_map);
1542
1543        let parse_task = cx.background_spawn({
1544            let language = language.clone();
1545            let language_registry = language_registry.clone();
1546            async move {
1547                syntax_snapshot.reparse(&text, language_registry, language);
1548                syntax_snapshot
1549            }
1550        });
1551
1552        self.parse_status.0.send(ParseStatus::Parsing).unwrap();
1553        match cx
1554            .background_executor()
1555            .block_with_timeout(self.sync_parse_timeout, parse_task)
1556        {
1557            Ok(new_syntax_snapshot) => {
1558                self.did_finish_parsing(new_syntax_snapshot, cx);
1559                self.reparse = None;
1560            }
1561            Err(parse_task) => {
1562                self.reparse = Some(cx.spawn(async move |this, cx| {
1563                    let new_syntax_map = parse_task.await;
1564                    this.update(cx, move |this, cx| {
1565                        let grammar_changed =
1566                            this.language.as_ref().is_none_or(|current_language| {
1567                                !Arc::ptr_eq(&language, current_language)
1568                            });
1569                        let language_registry_changed = new_syntax_map
1570                            .contains_unknown_injections()
1571                            && language_registry.is_some_and(|registry| {
1572                                registry.version() != new_syntax_map.language_registry_version()
1573                            });
1574                        let parse_again = language_registry_changed
1575                            || grammar_changed
1576                            || this.version.changed_since(&parsed_version);
1577                        this.did_finish_parsing(new_syntax_map, cx);
1578                        this.reparse = None;
1579                        if parse_again {
1580                            this.reparse(cx);
1581                        }
1582                    })
1583                    .ok();
1584                }));
1585            }
1586        }
1587    }
1588
1589    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut Context<Self>) {
1590        self.was_changed();
1591        self.non_text_state_update_count += 1;
1592        self.syntax_map.lock().did_parse(syntax_snapshot);
1593        self.request_autoindent(cx);
1594        self.parse_status.0.send(ParseStatus::Idle).unwrap();
1595        cx.emit(BufferEvent::Reparsed);
1596        cx.notify();
1597    }
1598
1599    pub fn parse_status(&self) -> watch::Receiver<ParseStatus> {
1600        self.parse_status.1.clone()
1601    }
1602
1603    /// Assign to the buffer a set of diagnostics created by a given language server.
1604    pub fn update_diagnostics(
1605        &mut self,
1606        server_id: LanguageServerId,
1607        diagnostics: DiagnosticSet,
1608        cx: &mut Context<Self>,
1609    ) {
1610        let lamport_timestamp = self.text.lamport_clock.tick();
1611        let op = Operation::UpdateDiagnostics {
1612            server_id,
1613            diagnostics: diagnostics.iter().cloned().collect(),
1614            lamport_timestamp,
1615        };
1616
1617        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
1618        self.send_operation(op, true, cx);
1619    }
1620
1621    pub fn buffer_diagnostics(
1622        &self,
1623        for_server: Option<LanguageServerId>,
1624    ) -> Vec<&DiagnosticEntry<Anchor>> {
1625        match for_server {
1626            Some(server_id) => match self.diagnostics.binary_search_by_key(&server_id, |v| v.0) {
1627                Ok(idx) => self.diagnostics[idx].1.iter().collect(),
1628                Err(_) => Vec::new(),
1629            },
1630            None => self
1631                .diagnostics
1632                .iter()
1633                .flat_map(|(_, diagnostic_set)| diagnostic_set.iter())
1634                .collect(),
1635        }
1636    }
1637
1638    fn request_autoindent(&mut self, cx: &mut Context<Self>) {
1639        if let Some(indent_sizes) = self.compute_autoindents() {
1640            let indent_sizes = cx.background_spawn(indent_sizes);
1641            match cx
1642                .background_executor()
1643                .block_with_timeout(Duration::from_micros(500), indent_sizes)
1644            {
1645                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
1646                Err(indent_sizes) => {
1647                    self.pending_autoindent = Some(cx.spawn(async move |this, cx| {
1648                        let indent_sizes = indent_sizes.await;
1649                        this.update(cx, |this, cx| {
1650                            this.apply_autoindents(indent_sizes, cx);
1651                        })
1652                        .ok();
1653                    }));
1654                }
1655            }
1656        } else {
1657            self.autoindent_requests.clear();
1658            for tx in self.wait_for_autoindent_txs.drain(..) {
1659                tx.send(()).ok();
1660            }
1661        }
1662    }
1663
1664    fn compute_autoindents(
1665        &self,
1666    ) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>> + use<>> {
1667        let max_rows_between_yields = 100;
1668        let snapshot = self.snapshot();
1669        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
1670            return None;
1671        }
1672
1673        let autoindent_requests = self.autoindent_requests.clone();
1674        Some(async move {
1675            let mut indent_sizes = BTreeMap::<u32, (IndentSize, bool)>::new();
1676            for request in autoindent_requests {
1677                // Resolve each edited range to its row in the current buffer and in the
1678                // buffer before this batch of edits.
1679                let mut row_ranges = Vec::new();
1680                let mut old_to_new_rows = BTreeMap::new();
1681                let mut language_indent_sizes_by_new_row = Vec::new();
1682                for entry in &request.entries {
1683                    let position = entry.range.start;
1684                    let new_row = position.to_point(&snapshot).row;
1685                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
1686                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
1687
1688                    if !entry.first_line_is_new {
1689                        let old_row = position.to_point(&request.before_edit).row;
1690                        old_to_new_rows.insert(old_row, new_row);
1691                    }
1692                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
1693                }
1694
1695                // Build a map containing the suggested indentation for each of the edited lines
1696                // with respect to the state of the buffer before these edits. This map is keyed
1697                // by the rows for these lines in the current state of the buffer.
1698                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
1699                let old_edited_ranges =
1700                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
1701                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1702                let mut language_indent_size = IndentSize::default();
1703                for old_edited_range in old_edited_ranges {
1704                    let suggestions = request
1705                        .before_edit
1706                        .suggest_autoindents(old_edited_range.clone())
1707                        .into_iter()
1708                        .flatten();
1709                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1710                        if let Some(suggestion) = suggestion {
1711                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
1712
1713                            // Find the indent size based on the language for this row.
1714                            while let Some((row, size)) = language_indent_sizes.peek() {
1715                                if *row > new_row {
1716                                    break;
1717                                }
1718                                language_indent_size = *size;
1719                                language_indent_sizes.next();
1720                            }
1721
1722                            let suggested_indent = old_to_new_rows
1723                                .get(&suggestion.basis_row)
1724                                .and_then(|from_row| {
1725                                    Some(old_suggestions.get(from_row).copied()?.0)
1726                                })
1727                                .unwrap_or_else(|| {
1728                                    request
1729                                        .before_edit
1730                                        .indent_size_for_line(suggestion.basis_row)
1731                                })
1732                                .with_delta(suggestion.delta, language_indent_size);
1733                            old_suggestions
1734                                .insert(new_row, (suggested_indent, suggestion.within_error));
1735                        }
1736                    }
1737                    yield_now().await;
1738                }
1739
1740                // Compute new suggestions for each line, but only include them in the result
1741                // if they differ from the old suggestion for that line.
1742                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1743                let mut language_indent_size = IndentSize::default();
1744                for (row_range, original_indent_column) in row_ranges {
1745                    let new_edited_row_range = if request.is_block_mode {
1746                        row_range.start..row_range.start + 1
1747                    } else {
1748                        row_range.clone()
1749                    };
1750
1751                    let suggestions = snapshot
1752                        .suggest_autoindents(new_edited_row_range.clone())
1753                        .into_iter()
1754                        .flatten();
1755                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1756                        if let Some(suggestion) = suggestion {
1757                            // Find the indent size based on the language for this row.
1758                            while let Some((row, size)) = language_indent_sizes.peek() {
1759                                if *row > new_row {
1760                                    break;
1761                                }
1762                                language_indent_size = *size;
1763                                language_indent_sizes.next();
1764                            }
1765
1766                            let suggested_indent = indent_sizes
1767                                .get(&suggestion.basis_row)
1768                                .copied()
1769                                .map(|e| e.0)
1770                                .unwrap_or_else(|| {
1771                                    snapshot.indent_size_for_line(suggestion.basis_row)
1772                                })
1773                                .with_delta(suggestion.delta, language_indent_size);
1774
1775                            if old_suggestions.get(&new_row).is_none_or(
1776                                |(old_indentation, was_within_error)| {
1777                                    suggested_indent != *old_indentation
1778                                        && (!suggestion.within_error || *was_within_error)
1779                                },
1780                            ) {
1781                                indent_sizes.insert(
1782                                    new_row,
1783                                    (suggested_indent, request.ignore_empty_lines),
1784                                );
1785                            }
1786                        }
1787                    }
1788
1789                    if let (true, Some(original_indent_column)) =
1790                        (request.is_block_mode, original_indent_column)
1791                    {
1792                        let new_indent =
1793                            if let Some((indent, _)) = indent_sizes.get(&row_range.start) {
1794                                *indent
1795                            } else {
1796                                snapshot.indent_size_for_line(row_range.start)
1797                            };
1798                        let delta = new_indent.len as i64 - original_indent_column as i64;
1799                        if delta != 0 {
1800                            for row in row_range.skip(1) {
1801                                indent_sizes.entry(row).or_insert_with(|| {
1802                                    let mut size = snapshot.indent_size_for_line(row);
1803                                    if size.kind == new_indent.kind {
1804                                        match delta.cmp(&0) {
1805                                            Ordering::Greater => size.len += delta as u32,
1806                                            Ordering::Less => {
1807                                                size.len = size.len.saturating_sub(-delta as u32)
1808                                            }
1809                                            Ordering::Equal => {}
1810                                        }
1811                                    }
1812                                    (size, request.ignore_empty_lines)
1813                                });
1814                            }
1815                        }
1816                    }
1817
1818                    yield_now().await;
1819                }
1820            }
1821
1822            indent_sizes
1823                .into_iter()
1824                .filter_map(|(row, (indent, ignore_empty_lines))| {
1825                    if ignore_empty_lines && snapshot.line_len(row) == 0 {
1826                        None
1827                    } else {
1828                        Some((row, indent))
1829                    }
1830                })
1831                .collect()
1832        })
1833    }
1834
1835    fn apply_autoindents(
1836        &mut self,
1837        indent_sizes: BTreeMap<u32, IndentSize>,
1838        cx: &mut Context<Self>,
1839    ) {
1840        self.autoindent_requests.clear();
1841        for tx in self.wait_for_autoindent_txs.drain(..) {
1842            tx.send(()).ok();
1843        }
1844
1845        let edits: Vec<_> = indent_sizes
1846            .into_iter()
1847            .filter_map(|(row, indent_size)| {
1848                let current_size = indent_size_for_line(self, row);
1849                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1850            })
1851            .collect();
1852
1853        let preserve_preview = self.preserve_preview();
1854        self.edit(edits, None, cx);
1855        if preserve_preview {
1856            self.refresh_preview();
1857        }
1858    }
1859
1860    /// Create a minimal edit that will cause the given row to be indented
1861    /// with the given size. After applying this edit, the length of the line
1862    /// will always be at least `new_size.len`.
1863    pub fn edit_for_indent_size_adjustment(
1864        row: u32,
1865        current_size: IndentSize,
1866        new_size: IndentSize,
1867    ) -> Option<(Range<Point>, String)> {
1868        if new_size.kind == current_size.kind {
1869            match new_size.len.cmp(&current_size.len) {
1870                Ordering::Greater => {
1871                    let point = Point::new(row, 0);
1872                    Some((
1873                        point..point,
1874                        iter::repeat(new_size.char())
1875                            .take((new_size.len - current_size.len) as usize)
1876                            .collect::<String>(),
1877                    ))
1878                }
1879
1880                Ordering::Less => Some((
1881                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1882                    String::new(),
1883                )),
1884
1885                Ordering::Equal => None,
1886            }
1887        } else {
1888            Some((
1889                Point::new(row, 0)..Point::new(row, current_size.len),
1890                iter::repeat(new_size.char())
1891                    .take(new_size.len as usize)
1892                    .collect::<String>(),
1893            ))
1894        }
1895    }
1896
1897    /// Spawns a background task that asynchronously computes a `Diff` between the buffer's text
1898    /// and the given new text.
1899    pub fn diff(&self, mut new_text: String, cx: &App) -> Task<Diff> {
1900        let old_text = self.as_rope().clone();
1901        let base_version = self.version();
1902        cx.background_executor()
1903            .spawn_labeled(*BUFFER_DIFF_TASK, async move {
1904                let old_text = old_text.to_string();
1905                let line_ending = LineEnding::detect(&new_text);
1906                LineEnding::normalize(&mut new_text);
1907                let edits = text_diff(&old_text, &new_text);
1908                Diff {
1909                    base_version,
1910                    line_ending,
1911                    edits,
1912                }
1913            })
1914    }
1915
1916    /// Spawns a background task that searches the buffer for any whitespace
1917    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1918    pub fn remove_trailing_whitespace(&self, cx: &App) -> Task<Diff> {
1919        let old_text = self.as_rope().clone();
1920        let line_ending = self.line_ending();
1921        let base_version = self.version();
1922        cx.background_spawn(async move {
1923            let ranges = trailing_whitespace_ranges(&old_text);
1924            let empty = Arc::<str>::from("");
1925            Diff {
1926                base_version,
1927                line_ending,
1928                edits: ranges
1929                    .into_iter()
1930                    .map(|range| (range, empty.clone()))
1931                    .collect(),
1932            }
1933        })
1934    }
1935
1936    /// Ensures that the buffer ends with a single newline character, and
1937    /// no other whitespace. Skips if the buffer is empty.
1938    pub fn ensure_final_newline(&mut self, cx: &mut Context<Self>) {
1939        let len = self.len();
1940        if len == 0 {
1941            return;
1942        }
1943        let mut offset = len;
1944        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1945            let non_whitespace_len = chunk
1946                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1947                .len();
1948            offset -= chunk.len();
1949            offset += non_whitespace_len;
1950            if non_whitespace_len != 0 {
1951                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1952                    return;
1953                }
1954                break;
1955            }
1956        }
1957        self.edit([(offset..len, "\n")], None, cx);
1958    }
1959
1960    /// Applies a diff to the buffer. If the buffer has changed since the given diff was
1961    /// calculated, then adjust the diff to account for those changes, and discard any
1962    /// parts of the diff that conflict with those changes.
1963    pub fn apply_diff(&mut self, diff: Diff, cx: &mut Context<Self>) -> Option<TransactionId> {
1964        let snapshot = self.snapshot();
1965        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1966        let mut delta = 0;
1967        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1968            while let Some(edit_since) = edits_since.peek() {
1969                // If the edit occurs after a diff hunk, then it does not
1970                // affect that hunk.
1971                if edit_since.old.start > range.end {
1972                    break;
1973                }
1974                // If the edit precedes the diff hunk, then adjust the hunk
1975                // to reflect the edit.
1976                else if edit_since.old.end < range.start {
1977                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1978                    edits_since.next();
1979                }
1980                // If the edit intersects a diff hunk, then discard that hunk.
1981                else {
1982                    return None;
1983                }
1984            }
1985
1986            let start = (range.start as i64 + delta) as usize;
1987            let end = (range.end as i64 + delta) as usize;
1988            Some((start..end, new_text))
1989        });
1990
1991        self.start_transaction();
1992        self.text.set_line_ending(diff.line_ending);
1993        self.edit(adjusted_edits, None, cx);
1994        self.end_transaction(cx)
1995    }
1996
1997    fn has_unsaved_edits(&self) -> bool {
1998        let (last_version, has_unsaved_edits) = self.has_unsaved_edits.take();
1999
2000        if last_version == self.version {
2001            self.has_unsaved_edits
2002                .set((last_version, has_unsaved_edits));
2003            return has_unsaved_edits;
2004        }
2005
2006        let has_edits = self.has_edits_since(&self.saved_version);
2007        self.has_unsaved_edits
2008            .set((self.version.clone(), has_edits));
2009        has_edits
2010    }
2011
2012    /// Checks if the buffer has unsaved changes.
2013    pub fn is_dirty(&self) -> bool {
2014        if self.capability == Capability::ReadOnly {
2015            return false;
2016        }
2017        if self.has_conflict {
2018            return true;
2019        }
2020        match self.file.as_ref().map(|f| f.disk_state()) {
2021            Some(DiskState::New) | Some(DiskState::Deleted) => {
2022                !self.is_empty() && self.has_unsaved_edits()
2023            }
2024            _ => self.has_unsaved_edits(),
2025        }
2026    }
2027
2028    /// Checks if the buffer and its file have both changed since the buffer
2029    /// was last saved or reloaded.
2030    pub fn has_conflict(&self) -> bool {
2031        if self.has_conflict {
2032            return true;
2033        }
2034        let Some(file) = self.file.as_ref() else {
2035            return false;
2036        };
2037        match file.disk_state() {
2038            DiskState::New => false,
2039            DiskState::Present { mtime } => match self.saved_mtime {
2040                Some(saved_mtime) => {
2041                    mtime.bad_is_greater_than(saved_mtime) && self.has_unsaved_edits()
2042                }
2043                None => true,
2044            },
2045            DiskState::Deleted => false,
2046        }
2047    }
2048
2049    /// Gets a [`Subscription`] that tracks all of the changes to the buffer's text.
2050    pub fn subscribe(&mut self) -> Subscription {
2051        self.text.subscribe()
2052    }
2053
2054    /// Adds a bit to the list of bits that are set when the buffer's text changes.
2055    ///
2056    /// This allows downstream code to check if the buffer's text has changed without
2057    /// waiting for an effect cycle, which would be required if using eents.
2058    pub fn record_changes(&mut self, bit: rc::Weak<Cell<bool>>) {
2059        if let Err(ix) = self
2060            .change_bits
2061            .binary_search_by_key(&rc::Weak::as_ptr(&bit), rc::Weak::as_ptr)
2062        {
2063            self.change_bits.insert(ix, bit);
2064        }
2065    }
2066
2067    fn was_changed(&mut self) {
2068        self.change_bits.retain(|change_bit| {
2069            change_bit.upgrade().is_some_and(|bit| {
2070                bit.replace(true);
2071                true
2072            })
2073        });
2074    }
2075
2076    /// Starts a transaction, if one is not already in-progress. When undoing or
2077    /// redoing edits, all of the edits performed within a transaction are undone
2078    /// or redone together.
2079    pub fn start_transaction(&mut self) -> Option<TransactionId> {
2080        self.start_transaction_at(Instant::now())
2081    }
2082
2083    /// Starts a transaction, providing the current time. Subsequent transactions
2084    /// that occur within a short period of time will be grouped together. This
2085    /// is controlled by the buffer's undo grouping duration.
2086    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
2087        self.transaction_depth += 1;
2088        if self.was_dirty_before_starting_transaction.is_none() {
2089            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
2090        }
2091        self.text.start_transaction_at(now)
2092    }
2093
2094    /// Terminates the current transaction, if this is the outermost transaction.
2095    pub fn end_transaction(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2096        self.end_transaction_at(Instant::now(), cx)
2097    }
2098
2099    /// Terminates the current transaction, providing the current time. Subsequent transactions
2100    /// that occur within a short period of time will be grouped together. This
2101    /// is controlled by the buffer's undo grouping duration.
2102    pub fn end_transaction_at(
2103        &mut self,
2104        now: Instant,
2105        cx: &mut Context<Self>,
2106    ) -> Option<TransactionId> {
2107        assert!(self.transaction_depth > 0);
2108        self.transaction_depth -= 1;
2109        let was_dirty = if self.transaction_depth == 0 {
2110            self.was_dirty_before_starting_transaction.take().unwrap()
2111        } else {
2112            false
2113        };
2114        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
2115            self.did_edit(&start_version, was_dirty, cx);
2116            Some(transaction_id)
2117        } else {
2118            None
2119        }
2120    }
2121
2122    /// Manually add a transaction to the buffer's undo history.
2123    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
2124        self.text.push_transaction(transaction, now);
2125    }
2126
2127    /// Differs from `push_transaction` in that it does not clear the redo
2128    /// stack. Intended to be used to create a parent transaction to merge
2129    /// potential child transactions into.
2130    ///
2131    /// The caller is responsible for removing it from the undo history using
2132    /// `forget_transaction` if no edits are merged into it. Otherwise, if edits
2133    /// are merged into this transaction, the caller is responsible for ensuring
2134    /// the redo stack is cleared. The easiest way to ensure the redo stack is
2135    /// cleared is to create transactions with the usual `start_transaction` and
2136    /// `end_transaction` methods and merging the resulting transactions into
2137    /// the transaction created by this method
2138    pub fn push_empty_transaction(&mut self, now: Instant) -> TransactionId {
2139        self.text.push_empty_transaction(now)
2140    }
2141
2142    /// Prevent the last transaction from being grouped with any subsequent transactions,
2143    /// even if they occur with the buffer's undo grouping duration.
2144    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
2145        self.text.finalize_last_transaction()
2146    }
2147
2148    /// Manually group all changes since a given transaction.
2149    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
2150        self.text.group_until_transaction(transaction_id);
2151    }
2152
2153    /// Manually remove a transaction from the buffer's undo history
2154    pub fn forget_transaction(&mut self, transaction_id: TransactionId) -> Option<Transaction> {
2155        self.text.forget_transaction(transaction_id)
2156    }
2157
2158    /// Retrieve a transaction from the buffer's undo history
2159    pub fn get_transaction(&self, transaction_id: TransactionId) -> Option<&Transaction> {
2160        self.text.get_transaction(transaction_id)
2161    }
2162
2163    /// Manually merge two transactions in the buffer's undo history.
2164    pub fn merge_transactions(&mut self, transaction: TransactionId, destination: TransactionId) {
2165        self.text.merge_transactions(transaction, destination);
2166    }
2167
2168    /// Waits for the buffer to receive operations with the given timestamps.
2169    pub fn wait_for_edits<It: IntoIterator<Item = clock::Lamport>>(
2170        &mut self,
2171        edit_ids: It,
2172    ) -> impl Future<Output = Result<()>> + use<It> {
2173        self.text.wait_for_edits(edit_ids)
2174    }
2175
2176    /// Waits for the buffer to receive the operations necessary for resolving the given anchors.
2177    pub fn wait_for_anchors<It: IntoIterator<Item = Anchor>>(
2178        &mut self,
2179        anchors: It,
2180    ) -> impl 'static + Future<Output = Result<()>> + use<It> {
2181        self.text.wait_for_anchors(anchors)
2182    }
2183
2184    /// Waits for the buffer to receive operations up to the given version.
2185    pub fn wait_for_version(
2186        &mut self,
2187        version: clock::Global,
2188    ) -> impl Future<Output = Result<()>> + use<> {
2189        self.text.wait_for_version(version)
2190    }
2191
2192    /// Forces all futures returned by [`Buffer::wait_for_version`], [`Buffer::wait_for_edits`], or
2193    /// [`Buffer::wait_for_version`] to resolve with an error.
2194    pub fn give_up_waiting(&mut self) {
2195        self.text.give_up_waiting();
2196    }
2197
2198    pub fn wait_for_autoindent_applied(&mut self) -> Option<oneshot::Receiver<()>> {
2199        let mut rx = None;
2200        if !self.autoindent_requests.is_empty() {
2201            let channel = oneshot::channel();
2202            self.wait_for_autoindent_txs.push(channel.0);
2203            rx = Some(channel.1);
2204        }
2205        rx
2206    }
2207
2208    /// Stores a set of selections that should be broadcasted to all of the buffer's replicas.
2209    pub fn set_active_selections(
2210        &mut self,
2211        selections: Arc<[Selection<Anchor>]>,
2212        line_mode: bool,
2213        cursor_shape: CursorShape,
2214        cx: &mut Context<Self>,
2215    ) {
2216        let lamport_timestamp = self.text.lamport_clock.tick();
2217        self.remote_selections.insert(
2218            self.text.replica_id(),
2219            SelectionSet {
2220                selections: selections.clone(),
2221                lamport_timestamp,
2222                line_mode,
2223                cursor_shape,
2224            },
2225        );
2226        self.send_operation(
2227            Operation::UpdateSelections {
2228                selections,
2229                line_mode,
2230                lamport_timestamp,
2231                cursor_shape,
2232            },
2233            true,
2234            cx,
2235        );
2236        self.non_text_state_update_count += 1;
2237        cx.notify();
2238    }
2239
2240    /// Clears the selections, so that other replicas of the buffer do not see any selections for
2241    /// this replica.
2242    pub fn remove_active_selections(&mut self, cx: &mut Context<Self>) {
2243        if self
2244            .remote_selections
2245            .get(&self.text.replica_id())
2246            .is_none_or(|set| !set.selections.is_empty())
2247        {
2248            self.set_active_selections(Arc::default(), false, Default::default(), cx);
2249        }
2250    }
2251
2252    pub fn set_agent_selections(
2253        &mut self,
2254        selections: Arc<[Selection<Anchor>]>,
2255        line_mode: bool,
2256        cursor_shape: CursorShape,
2257        cx: &mut Context<Self>,
2258    ) {
2259        let lamport_timestamp = self.text.lamport_clock.tick();
2260        self.remote_selections.insert(
2261            AGENT_REPLICA_ID,
2262            SelectionSet {
2263                selections,
2264                lamport_timestamp,
2265                line_mode,
2266                cursor_shape,
2267            },
2268        );
2269        self.non_text_state_update_count += 1;
2270        cx.notify();
2271    }
2272
2273    pub fn remove_agent_selections(&mut self, cx: &mut Context<Self>) {
2274        self.set_agent_selections(Arc::default(), false, Default::default(), cx);
2275    }
2276
2277    /// Replaces the buffer's entire text.
2278    pub fn set_text<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2279    where
2280        T: Into<Arc<str>>,
2281    {
2282        self.autoindent_requests.clear();
2283        self.edit([(0..self.len(), text)], None, cx)
2284    }
2285
2286    /// Appends the given text to the end of the buffer.
2287    pub fn append<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2288    where
2289        T: Into<Arc<str>>,
2290    {
2291        self.edit([(self.len()..self.len(), text)], None, cx)
2292    }
2293
2294    /// Applies the given edits to the buffer. Each edit is specified as a range of text to
2295    /// delete, and a string of text to insert at that location.
2296    ///
2297    /// If an [`AutoindentMode`] is provided, then the buffer will enqueue an auto-indent
2298    /// request for the edited ranges, which will be processed when the buffer finishes
2299    /// parsing.
2300    ///
2301    /// Parsing takes place at the end of a transaction, and may compute synchronously
2302    /// or asynchronously, depending on the changes.
2303    pub fn edit<I, S, T>(
2304        &mut self,
2305        edits_iter: I,
2306        autoindent_mode: Option<AutoindentMode>,
2307        cx: &mut Context<Self>,
2308    ) -> Option<clock::Lamport>
2309    where
2310        I: IntoIterator<Item = (Range<S>, T)>,
2311        S: ToOffset,
2312        T: Into<Arc<str>>,
2313    {
2314        // Skip invalid edits and coalesce contiguous ones.
2315        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
2316
2317        for (range, new_text) in edits_iter {
2318            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
2319
2320            if range.start > range.end {
2321                mem::swap(&mut range.start, &mut range.end);
2322            }
2323            let new_text = new_text.into();
2324            if !new_text.is_empty() || !range.is_empty() {
2325                if let Some((prev_range, prev_text)) = edits.last_mut()
2326                    && prev_range.end >= range.start
2327                {
2328                    prev_range.end = cmp::max(prev_range.end, range.end);
2329                    *prev_text = format!("{prev_text}{new_text}").into();
2330                } else {
2331                    edits.push((range, new_text));
2332                }
2333            }
2334        }
2335        if edits.is_empty() {
2336            return None;
2337        }
2338
2339        self.start_transaction();
2340        self.pending_autoindent.take();
2341        let autoindent_request = autoindent_mode
2342            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
2343
2344        let edit_operation = self.text.edit(edits.iter().cloned());
2345        let edit_id = edit_operation.timestamp();
2346
2347        if let Some((before_edit, mode)) = autoindent_request {
2348            let mut delta = 0isize;
2349            let mut previous_setting = None;
2350            let entries: Vec<_> = edits
2351                .into_iter()
2352                .enumerate()
2353                .zip(&edit_operation.as_edit().unwrap().new_text)
2354                .filter(|((_, (range, _)), _)| {
2355                    let language = before_edit.language_at(range.start);
2356                    let language_id = language.map(|l| l.id());
2357                    if let Some((cached_language_id, auto_indent)) = previous_setting
2358                        && cached_language_id == language_id
2359                    {
2360                        auto_indent
2361                    } else {
2362                        // The auto-indent setting is not present in editorconfigs, hence
2363                        // we can avoid passing the file here.
2364                        let auto_indent =
2365                            language_settings(language.map(|l| l.name()), None, cx).auto_indent;
2366                        previous_setting = Some((language_id, auto_indent));
2367                        auto_indent
2368                    }
2369                })
2370                .map(|((ix, (range, _)), new_text)| {
2371                    let new_text_length = new_text.len();
2372                    let old_start = range.start.to_point(&before_edit);
2373                    let new_start = (delta + range.start as isize) as usize;
2374                    let range_len = range.end - range.start;
2375                    delta += new_text_length as isize - range_len as isize;
2376
2377                    // Decide what range of the insertion to auto-indent, and whether
2378                    // the first line of the insertion should be considered a newly-inserted line
2379                    // or an edit to an existing line.
2380                    let mut range_of_insertion_to_indent = 0..new_text_length;
2381                    let mut first_line_is_new = true;
2382
2383                    let old_line_start = before_edit.indent_size_for_line(old_start.row).len;
2384                    let old_line_end = before_edit.line_len(old_start.row);
2385
2386                    if old_start.column > old_line_start {
2387                        first_line_is_new = false;
2388                    }
2389
2390                    if !new_text.contains('\n')
2391                        && (old_start.column + (range_len as u32) < old_line_end
2392                            || old_line_end == old_line_start)
2393                    {
2394                        first_line_is_new = false;
2395                    }
2396
2397                    // When inserting text starting with a newline, avoid auto-indenting the
2398                    // previous line.
2399                    if new_text.starts_with('\n') {
2400                        range_of_insertion_to_indent.start += 1;
2401                        first_line_is_new = true;
2402                    }
2403
2404                    let mut original_indent_column = None;
2405                    if let AutoindentMode::Block {
2406                        original_indent_columns,
2407                    } = &mode
2408                    {
2409                        original_indent_column = Some(if new_text.starts_with('\n') {
2410                            indent_size_for_text(
2411                                new_text[range_of_insertion_to_indent.clone()].chars(),
2412                            )
2413                            .len
2414                        } else {
2415                            original_indent_columns
2416                                .get(ix)
2417                                .copied()
2418                                .flatten()
2419                                .unwrap_or_else(|| {
2420                                    indent_size_for_text(
2421                                        new_text[range_of_insertion_to_indent.clone()].chars(),
2422                                    )
2423                                    .len
2424                                })
2425                        });
2426
2427                        // Avoid auto-indenting the line after the edit.
2428                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
2429                            range_of_insertion_to_indent.end -= 1;
2430                        }
2431                    }
2432
2433                    AutoindentRequestEntry {
2434                        first_line_is_new,
2435                        original_indent_column,
2436                        indent_size: before_edit.language_indent_size_at(range.start, cx),
2437                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
2438                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
2439                    }
2440                })
2441                .collect();
2442
2443            if !entries.is_empty() {
2444                self.autoindent_requests.push(Arc::new(AutoindentRequest {
2445                    before_edit,
2446                    entries,
2447                    is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
2448                    ignore_empty_lines: false,
2449                }));
2450            }
2451        }
2452
2453        self.end_transaction(cx);
2454        self.send_operation(Operation::Buffer(edit_operation), true, cx);
2455        Some(edit_id)
2456    }
2457
2458    fn did_edit(&mut self, old_version: &clock::Global, was_dirty: bool, cx: &mut Context<Self>) {
2459        self.was_changed();
2460
2461        if self.edits_since::<usize>(old_version).next().is_none() {
2462            return;
2463        }
2464
2465        self.reparse(cx);
2466        cx.emit(BufferEvent::Edited);
2467        if was_dirty != self.is_dirty() {
2468            cx.emit(BufferEvent::DirtyChanged);
2469        }
2470        cx.notify();
2471    }
2472
2473    pub fn autoindent_ranges<I, T>(&mut self, ranges: I, cx: &mut Context<Self>)
2474    where
2475        I: IntoIterator<Item = Range<T>>,
2476        T: ToOffset + Copy,
2477    {
2478        let before_edit = self.snapshot();
2479        let entries = ranges
2480            .into_iter()
2481            .map(|range| AutoindentRequestEntry {
2482                range: before_edit.anchor_before(range.start)..before_edit.anchor_after(range.end),
2483                first_line_is_new: true,
2484                indent_size: before_edit.language_indent_size_at(range.start, cx),
2485                original_indent_column: None,
2486            })
2487            .collect();
2488        self.autoindent_requests.push(Arc::new(AutoindentRequest {
2489            before_edit,
2490            entries,
2491            is_block_mode: false,
2492            ignore_empty_lines: true,
2493        }));
2494        self.request_autoindent(cx);
2495    }
2496
2497    // Inserts newlines at the given position to create an empty line, returning the start of the new line.
2498    // You can also request the insertion of empty lines above and below the line starting at the returned point.
2499    pub fn insert_empty_line(
2500        &mut self,
2501        position: impl ToPoint,
2502        space_above: bool,
2503        space_below: bool,
2504        cx: &mut Context<Self>,
2505    ) -> Point {
2506        let mut position = position.to_point(self);
2507
2508        self.start_transaction();
2509
2510        self.edit(
2511            [(position..position, "\n")],
2512            Some(AutoindentMode::EachLine),
2513            cx,
2514        );
2515
2516        if position.column > 0 {
2517            position += Point::new(1, 0);
2518        }
2519
2520        if !self.is_line_blank(position.row) {
2521            self.edit(
2522                [(position..position, "\n")],
2523                Some(AutoindentMode::EachLine),
2524                cx,
2525            );
2526        }
2527
2528        if space_above && position.row > 0 && !self.is_line_blank(position.row - 1) {
2529            self.edit(
2530                [(position..position, "\n")],
2531                Some(AutoindentMode::EachLine),
2532                cx,
2533            );
2534            position.row += 1;
2535        }
2536
2537        if space_below
2538            && (position.row == self.max_point().row || !self.is_line_blank(position.row + 1))
2539        {
2540            self.edit(
2541                [(position..position, "\n")],
2542                Some(AutoindentMode::EachLine),
2543                cx,
2544            );
2545        }
2546
2547        self.end_transaction(cx);
2548
2549        position
2550    }
2551
2552    /// Applies the given remote operations to the buffer.
2553    pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I, cx: &mut Context<Self>) {
2554        self.pending_autoindent.take();
2555        let was_dirty = self.is_dirty();
2556        let old_version = self.version.clone();
2557        let mut deferred_ops = Vec::new();
2558        let buffer_ops = ops
2559            .into_iter()
2560            .filter_map(|op| match op {
2561                Operation::Buffer(op) => Some(op),
2562                _ => {
2563                    if self.can_apply_op(&op) {
2564                        self.apply_op(op, cx);
2565                    } else {
2566                        deferred_ops.push(op);
2567                    }
2568                    None
2569                }
2570            })
2571            .collect::<Vec<_>>();
2572        for operation in buffer_ops.iter() {
2573            self.send_operation(Operation::Buffer(operation.clone()), false, cx);
2574        }
2575        self.text.apply_ops(buffer_ops);
2576        self.deferred_ops.insert(deferred_ops);
2577        self.flush_deferred_ops(cx);
2578        self.did_edit(&old_version, was_dirty, cx);
2579        // Notify independently of whether the buffer was edited as the operations could include a
2580        // selection update.
2581        cx.notify();
2582    }
2583
2584    fn flush_deferred_ops(&mut self, cx: &mut Context<Self>) {
2585        let mut deferred_ops = Vec::new();
2586        for op in self.deferred_ops.drain().iter().cloned() {
2587            if self.can_apply_op(&op) {
2588                self.apply_op(op, cx);
2589            } else {
2590                deferred_ops.push(op);
2591            }
2592        }
2593        self.deferred_ops.insert(deferred_ops);
2594    }
2595
2596    pub fn has_deferred_ops(&self) -> bool {
2597        !self.deferred_ops.is_empty() || self.text.has_deferred_ops()
2598    }
2599
2600    fn can_apply_op(&self, operation: &Operation) -> bool {
2601        match operation {
2602            Operation::Buffer(_) => {
2603                unreachable!("buffer operations should never be applied at this layer")
2604            }
2605            Operation::UpdateDiagnostics {
2606                diagnostics: diagnostic_set,
2607                ..
2608            } => diagnostic_set.iter().all(|diagnostic| {
2609                self.text.can_resolve(&diagnostic.range.start)
2610                    && self.text.can_resolve(&diagnostic.range.end)
2611            }),
2612            Operation::UpdateSelections { selections, .. } => selections
2613                .iter()
2614                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
2615            Operation::UpdateCompletionTriggers { .. } | Operation::UpdateLineEnding { .. } => true,
2616        }
2617    }
2618
2619    fn apply_op(&mut self, operation: Operation, cx: &mut Context<Self>) {
2620        match operation {
2621            Operation::Buffer(_) => {
2622                unreachable!("buffer operations should never be applied at this layer")
2623            }
2624            Operation::UpdateDiagnostics {
2625                server_id,
2626                diagnostics: diagnostic_set,
2627                lamport_timestamp,
2628            } => {
2629                let snapshot = self.snapshot();
2630                self.apply_diagnostic_update(
2631                    server_id,
2632                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
2633                    lamport_timestamp,
2634                    cx,
2635                );
2636            }
2637            Operation::UpdateSelections {
2638                selections,
2639                lamport_timestamp,
2640                line_mode,
2641                cursor_shape,
2642            } => {
2643                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id)
2644                    && set.lamport_timestamp > lamport_timestamp
2645                {
2646                    return;
2647                }
2648
2649                self.remote_selections.insert(
2650                    lamport_timestamp.replica_id,
2651                    SelectionSet {
2652                        selections,
2653                        lamport_timestamp,
2654                        line_mode,
2655                        cursor_shape,
2656                    },
2657                );
2658                self.text.lamport_clock.observe(lamport_timestamp);
2659                self.non_text_state_update_count += 1;
2660            }
2661            Operation::UpdateCompletionTriggers {
2662                triggers,
2663                lamport_timestamp,
2664                server_id,
2665            } => {
2666                if triggers.is_empty() {
2667                    self.completion_triggers_per_language_server
2668                        .remove(&server_id);
2669                    self.completion_triggers = self
2670                        .completion_triggers_per_language_server
2671                        .values()
2672                        .flat_map(|triggers| triggers.iter().cloned())
2673                        .collect();
2674                } else {
2675                    self.completion_triggers_per_language_server
2676                        .insert(server_id, triggers.iter().cloned().collect());
2677                    self.completion_triggers.extend(triggers);
2678                }
2679                self.text.lamport_clock.observe(lamport_timestamp);
2680            }
2681            Operation::UpdateLineEnding {
2682                line_ending,
2683                lamport_timestamp,
2684            } => {
2685                self.text.set_line_ending(line_ending);
2686                self.text.lamport_clock.observe(lamport_timestamp);
2687            }
2688        }
2689    }
2690
2691    fn apply_diagnostic_update(
2692        &mut self,
2693        server_id: LanguageServerId,
2694        diagnostics: DiagnosticSet,
2695        lamport_timestamp: clock::Lamport,
2696        cx: &mut Context<Self>,
2697    ) {
2698        if lamport_timestamp > self.diagnostics_timestamp {
2699            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
2700            if diagnostics.is_empty() {
2701                if let Ok(ix) = ix {
2702                    self.diagnostics.remove(ix);
2703                }
2704            } else {
2705                match ix {
2706                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
2707                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
2708                };
2709            }
2710            self.diagnostics_timestamp = lamport_timestamp;
2711            self.non_text_state_update_count += 1;
2712            self.text.lamport_clock.observe(lamport_timestamp);
2713            cx.notify();
2714            cx.emit(BufferEvent::DiagnosticsUpdated);
2715        }
2716    }
2717
2718    fn send_operation(&mut self, operation: Operation, is_local: bool, cx: &mut Context<Self>) {
2719        self.was_changed();
2720        cx.emit(BufferEvent::Operation {
2721            operation,
2722            is_local,
2723        });
2724    }
2725
2726    /// Removes the selections for a given peer.
2727    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut Context<Self>) {
2728        self.remote_selections.remove(&replica_id);
2729        cx.notify();
2730    }
2731
2732    /// Undoes the most recent transaction.
2733    pub fn undo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2734        let was_dirty = self.is_dirty();
2735        let old_version = self.version.clone();
2736
2737        if let Some((transaction_id, operation)) = self.text.undo() {
2738            self.send_operation(Operation::Buffer(operation), true, cx);
2739            self.did_edit(&old_version, was_dirty, cx);
2740            Some(transaction_id)
2741        } else {
2742            None
2743        }
2744    }
2745
2746    /// Manually undoes a specific transaction in the buffer's undo history.
2747    pub fn undo_transaction(
2748        &mut self,
2749        transaction_id: TransactionId,
2750        cx: &mut Context<Self>,
2751    ) -> bool {
2752        let was_dirty = self.is_dirty();
2753        let old_version = self.version.clone();
2754        if let Some(operation) = self.text.undo_transaction(transaction_id) {
2755            self.send_operation(Operation::Buffer(operation), true, cx);
2756            self.did_edit(&old_version, was_dirty, cx);
2757            true
2758        } else {
2759            false
2760        }
2761    }
2762
2763    /// Manually undoes all changes after a given transaction in the buffer's undo history.
2764    pub fn undo_to_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
2772        let operations = self.text.undo_to_transaction(transaction_id);
2773        let undone = !operations.is_empty();
2774        for operation in operations {
2775            self.send_operation(Operation::Buffer(operation), true, cx);
2776        }
2777        if undone {
2778            self.did_edit(&old_version, was_dirty, cx)
2779        }
2780        undone
2781    }
2782
2783    pub fn undo_operations(&mut self, counts: HashMap<Lamport, u32>, cx: &mut Context<Buffer>) {
2784        let was_dirty = self.is_dirty();
2785        let operation = self.text.undo_operations(counts);
2786        let old_version = self.version.clone();
2787        self.send_operation(Operation::Buffer(operation), true, cx);
2788        self.did_edit(&old_version, was_dirty, cx);
2789    }
2790
2791    /// Manually redoes a specific transaction in the buffer's redo history.
2792    pub fn redo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2793        let was_dirty = self.is_dirty();
2794        let old_version = self.version.clone();
2795
2796        if let Some((transaction_id, operation)) = self.text.redo() {
2797            self.send_operation(Operation::Buffer(operation), true, cx);
2798            self.did_edit(&old_version, was_dirty, cx);
2799            Some(transaction_id)
2800        } else {
2801            None
2802        }
2803    }
2804
2805    /// Manually undoes all changes until a given transaction in the buffer's redo history.
2806    pub fn redo_to_transaction(
2807        &mut self,
2808        transaction_id: TransactionId,
2809        cx: &mut Context<Self>,
2810    ) -> bool {
2811        let was_dirty = self.is_dirty();
2812        let old_version = self.version.clone();
2813
2814        let operations = self.text.redo_to_transaction(transaction_id);
2815        let redone = !operations.is_empty();
2816        for operation in operations {
2817            self.send_operation(Operation::Buffer(operation), true, cx);
2818        }
2819        if redone {
2820            self.did_edit(&old_version, was_dirty, cx)
2821        }
2822        redone
2823    }
2824
2825    /// Override current completion triggers with the user-provided completion triggers.
2826    pub fn set_completion_triggers(
2827        &mut self,
2828        server_id: LanguageServerId,
2829        triggers: BTreeSet<String>,
2830        cx: &mut Context<Self>,
2831    ) {
2832        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
2833        if triggers.is_empty() {
2834            self.completion_triggers_per_language_server
2835                .remove(&server_id);
2836            self.completion_triggers = self
2837                .completion_triggers_per_language_server
2838                .values()
2839                .flat_map(|triggers| triggers.iter().cloned())
2840                .collect();
2841        } else {
2842            self.completion_triggers_per_language_server
2843                .insert(server_id, triggers.clone());
2844            self.completion_triggers.extend(triggers.iter().cloned());
2845        }
2846        self.send_operation(
2847            Operation::UpdateCompletionTriggers {
2848                triggers: triggers.into_iter().collect(),
2849                lamport_timestamp: self.completion_triggers_timestamp,
2850                server_id,
2851            },
2852            true,
2853            cx,
2854        );
2855        cx.notify();
2856    }
2857
2858    /// Returns a list of strings which trigger a completion menu for this language.
2859    /// Usually this is driven by LSP server which returns a list of trigger characters for completions.
2860    pub fn completion_triggers(&self) -> &BTreeSet<String> {
2861        &self.completion_triggers
2862    }
2863
2864    /// Call this directly after performing edits to prevent the preview tab
2865    /// from being dismissed by those edits. It causes `should_dismiss_preview`
2866    /// to return false until there are additional edits.
2867    pub fn refresh_preview(&mut self) {
2868        self.preview_version = self.version.clone();
2869    }
2870
2871    /// Whether we should preserve the preview status of a tab containing this buffer.
2872    pub fn preserve_preview(&self) -> bool {
2873        !self.has_edits_since(&self.preview_version)
2874    }
2875}
2876
2877#[doc(hidden)]
2878#[cfg(any(test, feature = "test-support"))]
2879impl Buffer {
2880    pub fn edit_via_marked_text(
2881        &mut self,
2882        marked_string: &str,
2883        autoindent_mode: Option<AutoindentMode>,
2884        cx: &mut Context<Self>,
2885    ) {
2886        let edits = self.edits_for_marked_text(marked_string);
2887        self.edit(edits, autoindent_mode, cx);
2888    }
2889
2890    pub fn set_group_interval(&mut self, group_interval: Duration) {
2891        self.text.set_group_interval(group_interval);
2892    }
2893
2894    pub fn randomly_edit<T>(&mut self, rng: &mut T, old_range_count: usize, cx: &mut Context<Self>)
2895    where
2896        T: rand::Rng,
2897    {
2898        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
2899        let mut last_end = None;
2900        for _ in 0..old_range_count {
2901            if last_end.is_some_and(|last_end| last_end >= self.len()) {
2902                break;
2903            }
2904
2905            let new_start = last_end.map_or(0, |last_end| last_end + 1);
2906            let mut range = self.random_byte_range(new_start, rng);
2907            if rng.random_bool(0.2) {
2908                mem::swap(&mut range.start, &mut range.end);
2909            }
2910            last_end = Some(range.end);
2911
2912            let new_text_len = rng.random_range(0..10);
2913            let mut new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
2914            new_text = new_text.to_uppercase();
2915
2916            edits.push((range, new_text));
2917        }
2918        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
2919        self.edit(edits, None, cx);
2920    }
2921
2922    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut Context<Self>) {
2923        let was_dirty = self.is_dirty();
2924        let old_version = self.version.clone();
2925
2926        let ops = self.text.randomly_undo_redo(rng);
2927        if !ops.is_empty() {
2928            for op in ops {
2929                self.send_operation(Operation::Buffer(op), true, cx);
2930                self.did_edit(&old_version, was_dirty, cx);
2931            }
2932        }
2933    }
2934}
2935
2936impl EventEmitter<BufferEvent> for Buffer {}
2937
2938impl Deref for Buffer {
2939    type Target = TextBuffer;
2940
2941    fn deref(&self) -> &Self::Target {
2942        &self.text
2943    }
2944}
2945
2946impl BufferSnapshot {
2947    /// Returns [`IndentSize`] for a given line that respects user settings and
2948    /// language preferences.
2949    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
2950        indent_size_for_line(self, row)
2951    }
2952
2953    /// Returns [`IndentSize`] for a given position that respects user settings
2954    /// and language preferences.
2955    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &App) -> IndentSize {
2956        let settings = language_settings(
2957            self.language_at(position).map(|l| l.name()),
2958            self.file(),
2959            cx,
2960        );
2961        if settings.hard_tabs {
2962            IndentSize::tab()
2963        } else {
2964            IndentSize::spaces(settings.tab_size.get())
2965        }
2966    }
2967
2968    /// Retrieve the suggested indent size for all of the given rows. The unit of indentation
2969    /// is passed in as `single_indent_size`.
2970    pub fn suggested_indents(
2971        &self,
2972        rows: impl Iterator<Item = u32>,
2973        single_indent_size: IndentSize,
2974    ) -> BTreeMap<u32, IndentSize> {
2975        let mut result = BTreeMap::new();
2976
2977        for row_range in contiguous_ranges(rows, 10) {
2978            let suggestions = match self.suggest_autoindents(row_range.clone()) {
2979                Some(suggestions) => suggestions,
2980                _ => break,
2981            };
2982
2983            for (row, suggestion) in row_range.zip(suggestions) {
2984                let indent_size = if let Some(suggestion) = suggestion {
2985                    result
2986                        .get(&suggestion.basis_row)
2987                        .copied()
2988                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
2989                        .with_delta(suggestion.delta, single_indent_size)
2990                } else {
2991                    self.indent_size_for_line(row)
2992                };
2993
2994                result.insert(row, indent_size);
2995            }
2996        }
2997
2998        result
2999    }
3000
3001    fn suggest_autoindents(
3002        &self,
3003        row_range: Range<u32>,
3004    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
3005        let config = &self.language.as_ref()?.config;
3006        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
3007
3008        #[derive(Debug, Clone)]
3009        struct StartPosition {
3010            start: Point,
3011            suffix: SharedString,
3012        }
3013
3014        // Find the suggested indentation ranges based on the syntax tree.
3015        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
3016        let end = Point::new(row_range.end, 0);
3017        let range = (start..end).to_offset(&self.text);
3018        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3019            Some(&grammar.indents_config.as_ref()?.query)
3020        });
3021        let indent_configs = matches
3022            .grammars()
3023            .iter()
3024            .map(|grammar| grammar.indents_config.as_ref().unwrap())
3025            .collect::<Vec<_>>();
3026
3027        let mut indent_ranges = Vec::<Range<Point>>::new();
3028        let mut start_positions = Vec::<StartPosition>::new();
3029        let mut outdent_positions = Vec::<Point>::new();
3030        while let Some(mat) = matches.peek() {
3031            let mut start: Option<Point> = None;
3032            let mut end: Option<Point> = None;
3033
3034            let config = indent_configs[mat.grammar_index];
3035            for capture in mat.captures {
3036                if capture.index == config.indent_capture_ix {
3037                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
3038                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
3039                } else if Some(capture.index) == config.start_capture_ix {
3040                    start = Some(Point::from_ts_point(capture.node.end_position()));
3041                } else if Some(capture.index) == config.end_capture_ix {
3042                    end = Some(Point::from_ts_point(capture.node.start_position()));
3043                } else if Some(capture.index) == config.outdent_capture_ix {
3044                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
3045                } else if let Some(suffix) = config.suffixed_start_captures.get(&capture.index) {
3046                    start_positions.push(StartPosition {
3047                        start: Point::from_ts_point(capture.node.start_position()),
3048                        suffix: suffix.clone(),
3049                    });
3050                }
3051            }
3052
3053            matches.advance();
3054            if let Some((start, end)) = start.zip(end) {
3055                if start.row == end.row {
3056                    continue;
3057                }
3058                let range = start..end;
3059                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
3060                    Err(ix) => indent_ranges.insert(ix, range),
3061                    Ok(ix) => {
3062                        let prev_range = &mut indent_ranges[ix];
3063                        prev_range.end = prev_range.end.max(range.end);
3064                    }
3065                }
3066            }
3067        }
3068
3069        let mut error_ranges = Vec::<Range<Point>>::new();
3070        let mut matches = self
3071            .syntax
3072            .matches(range, &self.text, |grammar| grammar.error_query.as_ref());
3073        while let Some(mat) = matches.peek() {
3074            let node = mat.captures[0].node;
3075            let start = Point::from_ts_point(node.start_position());
3076            let end = Point::from_ts_point(node.end_position());
3077            let range = start..end;
3078            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
3079                Ok(ix) | Err(ix) => ix,
3080            };
3081            let mut end_ix = ix;
3082            while let Some(existing_range) = error_ranges.get(end_ix) {
3083                if existing_range.end < end {
3084                    end_ix += 1;
3085                } else {
3086                    break;
3087                }
3088            }
3089            error_ranges.splice(ix..end_ix, [range]);
3090            matches.advance();
3091        }
3092
3093        outdent_positions.sort();
3094        for outdent_position in outdent_positions {
3095            // find the innermost indent range containing this outdent_position
3096            // set its end to the outdent position
3097            if let Some(range_to_truncate) = indent_ranges
3098                .iter_mut()
3099                .filter(|indent_range| indent_range.contains(&outdent_position))
3100                .next_back()
3101            {
3102                range_to_truncate.end = outdent_position;
3103            }
3104        }
3105
3106        start_positions.sort_by_key(|b| b.start);
3107
3108        // Find the suggested indentation increases and decreased based on regexes.
3109        let mut regex_outdent_map = HashMap::default();
3110        let mut last_seen_suffix: HashMap<String, Vec<Point>> = HashMap::default();
3111        let mut start_positions_iter = start_positions.iter().peekable();
3112
3113        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
3114        self.for_each_line(
3115            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
3116                ..Point::new(row_range.end, 0),
3117            |row, line| {
3118                if config
3119                    .decrease_indent_pattern
3120                    .as_ref()
3121                    .is_some_and(|regex| regex.is_match(line))
3122                {
3123                    indent_change_rows.push((row, Ordering::Less));
3124                }
3125                if config
3126                    .increase_indent_pattern
3127                    .as_ref()
3128                    .is_some_and(|regex| regex.is_match(line))
3129                {
3130                    indent_change_rows.push((row + 1, Ordering::Greater));
3131                }
3132                while let Some(pos) = start_positions_iter.peek() {
3133                    if pos.start.row < row {
3134                        let pos = start_positions_iter.next().unwrap();
3135                        last_seen_suffix
3136                            .entry(pos.suffix.to_string())
3137                            .or_default()
3138                            .push(pos.start);
3139                    } else {
3140                        break;
3141                    }
3142                }
3143                for rule in &config.decrease_indent_patterns {
3144                    if rule.pattern.as_ref().is_some_and(|r| r.is_match(line)) {
3145                        let row_start_column = self.indent_size_for_line(row).len;
3146                        let basis_row = rule
3147                            .valid_after
3148                            .iter()
3149                            .filter_map(|valid_suffix| last_seen_suffix.get(valid_suffix))
3150                            .flatten()
3151                            .filter(|start_point| start_point.column <= row_start_column)
3152                            .max_by_key(|start_point| start_point.row);
3153                        if let Some(outdent_to_row) = basis_row {
3154                            regex_outdent_map.insert(row, outdent_to_row.row);
3155                        }
3156                        break;
3157                    }
3158                }
3159            },
3160        );
3161
3162        let mut indent_changes = indent_change_rows.into_iter().peekable();
3163        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
3164            prev_non_blank_row.unwrap_or(0)
3165        } else {
3166            row_range.start.saturating_sub(1)
3167        };
3168
3169        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
3170        Some(row_range.map(move |row| {
3171            let row_start = Point::new(row, self.indent_size_for_line(row).len);
3172
3173            let mut indent_from_prev_row = false;
3174            let mut outdent_from_prev_row = false;
3175            let mut outdent_to_row = u32::MAX;
3176            let mut from_regex = false;
3177
3178            while let Some((indent_row, delta)) = indent_changes.peek() {
3179                match indent_row.cmp(&row) {
3180                    Ordering::Equal => match delta {
3181                        Ordering::Less => {
3182                            from_regex = true;
3183                            outdent_from_prev_row = true
3184                        }
3185                        Ordering::Greater => {
3186                            indent_from_prev_row = true;
3187                            from_regex = true
3188                        }
3189                        _ => {}
3190                    },
3191
3192                    Ordering::Greater => break,
3193                    Ordering::Less => {}
3194                }
3195
3196                indent_changes.next();
3197            }
3198
3199            for range in &indent_ranges {
3200                if range.start.row >= row {
3201                    break;
3202                }
3203                if range.start.row == prev_row && range.end > row_start {
3204                    indent_from_prev_row = true;
3205                }
3206                if range.end > prev_row_start && range.end <= row_start {
3207                    outdent_to_row = outdent_to_row.min(range.start.row);
3208                }
3209            }
3210
3211            if let Some(basis_row) = regex_outdent_map.get(&row) {
3212                indent_from_prev_row = false;
3213                outdent_to_row = *basis_row;
3214                from_regex = true;
3215            }
3216
3217            let within_error = error_ranges
3218                .iter()
3219                .any(|e| e.start.row < row && e.end > row_start);
3220
3221            let suggestion = if outdent_to_row == prev_row
3222                || (outdent_from_prev_row && indent_from_prev_row)
3223            {
3224                Some(IndentSuggestion {
3225                    basis_row: prev_row,
3226                    delta: Ordering::Equal,
3227                    within_error: within_error && !from_regex,
3228                })
3229            } else if indent_from_prev_row {
3230                Some(IndentSuggestion {
3231                    basis_row: prev_row,
3232                    delta: Ordering::Greater,
3233                    within_error: within_error && !from_regex,
3234                })
3235            } else if outdent_to_row < prev_row {
3236                Some(IndentSuggestion {
3237                    basis_row: outdent_to_row,
3238                    delta: Ordering::Equal,
3239                    within_error: within_error && !from_regex,
3240                })
3241            } else if outdent_from_prev_row {
3242                Some(IndentSuggestion {
3243                    basis_row: prev_row,
3244                    delta: Ordering::Less,
3245                    within_error: within_error && !from_regex,
3246                })
3247            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
3248            {
3249                Some(IndentSuggestion {
3250                    basis_row: prev_row,
3251                    delta: Ordering::Equal,
3252                    within_error: within_error && !from_regex,
3253                })
3254            } else {
3255                None
3256            };
3257
3258            prev_row = row;
3259            prev_row_start = row_start;
3260            suggestion
3261        }))
3262    }
3263
3264    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
3265        while row > 0 {
3266            row -= 1;
3267            if !self.is_line_blank(row) {
3268                return Some(row);
3269            }
3270        }
3271        None
3272    }
3273
3274    fn get_highlights(&self, range: Range<usize>) -> (SyntaxMapCaptures<'_>, Vec<HighlightMap>) {
3275        let captures = self.syntax.captures(range, &self.text, |grammar| {
3276            grammar
3277                .highlights_config
3278                .as_ref()
3279                .map(|config| &config.query)
3280        });
3281        let highlight_maps = captures
3282            .grammars()
3283            .iter()
3284            .map(|grammar| grammar.highlight_map())
3285            .collect();
3286        (captures, highlight_maps)
3287    }
3288
3289    /// Iterates over chunks of text in the given range of the buffer. Text is chunked
3290    /// in an arbitrary way due to being stored in a [`Rope`](text::Rope). The text is also
3291    /// returned in chunks where each chunk has a single syntax highlighting style and
3292    /// diagnostic status.
3293    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks<'_> {
3294        let range = range.start.to_offset(self)..range.end.to_offset(self);
3295
3296        let mut syntax = None;
3297        if language_aware {
3298            syntax = Some(self.get_highlights(range.clone()));
3299        }
3300        // We want to look at diagnostic spans only when iterating over language-annotated chunks.
3301        let diagnostics = language_aware;
3302        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostics, Some(self))
3303    }
3304
3305    pub fn highlighted_text_for_range<T: ToOffset>(
3306        &self,
3307        range: Range<T>,
3308        override_style: Option<HighlightStyle>,
3309        syntax_theme: &SyntaxTheme,
3310    ) -> HighlightedText {
3311        HighlightedText::from_buffer_range(
3312            range,
3313            &self.text,
3314            &self.syntax,
3315            override_style,
3316            syntax_theme,
3317        )
3318    }
3319
3320    /// Invokes the given callback for each line of text in the given range of the buffer.
3321    /// Uses callback to avoid allocating a string for each line.
3322    fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
3323        let mut line = String::new();
3324        let mut row = range.start.row;
3325        for chunk in self
3326            .as_rope()
3327            .chunks_in_range(range.to_offset(self))
3328            .chain(["\n"])
3329        {
3330            for (newline_ix, text) in chunk.split('\n').enumerate() {
3331                if newline_ix > 0 {
3332                    callback(row, &line);
3333                    row += 1;
3334                    line.clear();
3335                }
3336                line.push_str(text);
3337            }
3338        }
3339    }
3340
3341    /// Iterates over every [`SyntaxLayer`] in the buffer.
3342    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayer<'_>> + '_ {
3343        self.syntax_layers_for_range(0..self.len(), true)
3344    }
3345
3346    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayer<'_>> {
3347        let offset = position.to_offset(self);
3348        self.syntax_layers_for_range(offset..offset, false)
3349            .filter(|l| l.node().end_byte() > offset)
3350            .last()
3351    }
3352
3353    pub fn syntax_layers_for_range<D: ToOffset>(
3354        &self,
3355        range: Range<D>,
3356        include_hidden: bool,
3357    ) -> impl Iterator<Item = SyntaxLayer<'_>> + '_ {
3358        self.syntax
3359            .layers_for_range(range, &self.text, include_hidden)
3360    }
3361
3362    pub fn smallest_syntax_layer_containing<D: ToOffset>(
3363        &self,
3364        range: Range<D>,
3365    ) -> Option<SyntaxLayer<'_>> {
3366        let range = range.to_offset(self);
3367        self.syntax
3368            .layers_for_range(range, &self.text, false)
3369            .max_by(|a, b| {
3370                if a.depth != b.depth {
3371                    a.depth.cmp(&b.depth)
3372                } else if a.offset.0 != b.offset.0 {
3373                    a.offset.0.cmp(&b.offset.0)
3374                } else {
3375                    a.node().end_byte().cmp(&b.node().end_byte()).reverse()
3376                }
3377            })
3378    }
3379
3380    /// Returns the main [`Language`].
3381    pub fn language(&self) -> Option<&Arc<Language>> {
3382        self.language.as_ref()
3383    }
3384
3385    /// Returns the [`Language`] at the given location.
3386    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
3387        self.syntax_layer_at(position)
3388            .map(|info| info.language)
3389            .or(self.language.as_ref())
3390    }
3391
3392    /// Returns the settings for the language at the given location.
3393    pub fn settings_at<'a, D: ToOffset>(
3394        &'a self,
3395        position: D,
3396        cx: &'a App,
3397    ) -> Cow<'a, LanguageSettings> {
3398        language_settings(
3399            self.language_at(position).map(|l| l.name()),
3400            self.file.as_ref(),
3401            cx,
3402        )
3403    }
3404
3405    pub fn char_classifier_at<T: ToOffset>(&self, point: T) -> CharClassifier {
3406        CharClassifier::new(self.language_scope_at(point))
3407    }
3408
3409    /// Returns the [`LanguageScope`] at the given location.
3410    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
3411        let offset = position.to_offset(self);
3412        let mut scope = None;
3413        let mut smallest_range_and_depth: Option<(Range<usize>, usize)> = None;
3414
3415        // Use the layer that has the smallest node intersecting the given point.
3416        for layer in self
3417            .syntax
3418            .layers_for_range(offset..offset, &self.text, false)
3419        {
3420            let mut cursor = layer.node().walk();
3421
3422            let mut range = None;
3423            loop {
3424                let child_range = cursor.node().byte_range();
3425                if !child_range.contains(&offset) {
3426                    break;
3427                }
3428
3429                range = Some(child_range);
3430                if cursor.goto_first_child_for_byte(offset).is_none() {
3431                    break;
3432                }
3433            }
3434
3435            if let Some(range) = range
3436                && smallest_range_and_depth.as_ref().is_none_or(
3437                    |(smallest_range, smallest_range_depth)| {
3438                        if layer.depth > *smallest_range_depth {
3439                            true
3440                        } else if layer.depth == *smallest_range_depth {
3441                            range.len() < smallest_range.len()
3442                        } else {
3443                            false
3444                        }
3445                    },
3446                )
3447            {
3448                smallest_range_and_depth = Some((range, layer.depth));
3449                scope = Some(LanguageScope {
3450                    language: layer.language.clone(),
3451                    override_id: layer.override_id(offset, &self.text),
3452                });
3453            }
3454        }
3455
3456        scope.or_else(|| {
3457            self.language.clone().map(|language| LanguageScope {
3458                language,
3459                override_id: None,
3460            })
3461        })
3462    }
3463
3464    /// Returns a tuple of the range and character kind of the word
3465    /// surrounding the given position.
3466    pub fn surrounding_word<T: ToOffset>(
3467        &self,
3468        start: T,
3469        scope_context: Option<CharScopeContext>,
3470    ) -> (Range<usize>, Option<CharKind>) {
3471        let mut start = start.to_offset(self);
3472        let mut end = start;
3473        let mut next_chars = self.chars_at(start).take(128).peekable();
3474        let mut prev_chars = self.reversed_chars_at(start).take(128).peekable();
3475
3476        let classifier = self.char_classifier_at(start).scope_context(scope_context);
3477        let word_kind = cmp::max(
3478            prev_chars.peek().copied().map(|c| classifier.kind(c)),
3479            next_chars.peek().copied().map(|c| classifier.kind(c)),
3480        );
3481
3482        for ch in prev_chars {
3483            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3484                start -= ch.len_utf8();
3485            } else {
3486                break;
3487            }
3488        }
3489
3490        for ch in next_chars {
3491            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3492                end += ch.len_utf8();
3493            } else {
3494                break;
3495            }
3496        }
3497
3498        (start..end, word_kind)
3499    }
3500
3501    /// Moves the TreeCursor to the smallest descendant or ancestor syntax node enclosing the given
3502    /// range. When `require_larger` is true, the node found must be larger than the query range.
3503    ///
3504    /// Returns true if a node was found, and false otherwise. In the `false` case the cursor will
3505    /// be moved to the root of the tree.
3506    fn goto_node_enclosing_range(
3507        cursor: &mut tree_sitter::TreeCursor,
3508        query_range: &Range<usize>,
3509        require_larger: bool,
3510    ) -> bool {
3511        let mut ascending = false;
3512        loop {
3513            let mut range = cursor.node().byte_range();
3514            if query_range.is_empty() {
3515                // When the query range is empty and the current node starts after it, move to the
3516                // previous sibling to find the node the containing node.
3517                if range.start > query_range.start {
3518                    cursor.goto_previous_sibling();
3519                    range = cursor.node().byte_range();
3520                }
3521            } else {
3522                // When the query range is non-empty and the current node ends exactly at the start,
3523                // move to the next sibling to find a node that extends beyond the start.
3524                if range.end == query_range.start {
3525                    cursor.goto_next_sibling();
3526                    range = cursor.node().byte_range();
3527                }
3528            }
3529
3530            let encloses = range.contains_inclusive(query_range)
3531                && (!require_larger || range.len() > query_range.len());
3532            if !encloses {
3533                ascending = true;
3534                if !cursor.goto_parent() {
3535                    return false;
3536                }
3537                continue;
3538            } else if ascending {
3539                return true;
3540            }
3541
3542            // Descend into the current node.
3543            if cursor
3544                .goto_first_child_for_byte(query_range.start)
3545                .is_none()
3546            {
3547                return true;
3548            }
3549        }
3550    }
3551
3552    pub fn syntax_ancestor<'a, T: ToOffset>(
3553        &'a self,
3554        range: Range<T>,
3555    ) -> Option<tree_sitter::Node<'a>> {
3556        let range = range.start.to_offset(self)..range.end.to_offset(self);
3557        let mut result: Option<tree_sitter::Node<'a>> = None;
3558        for layer in self
3559            .syntax
3560            .layers_for_range(range.clone(), &self.text, true)
3561        {
3562            let mut cursor = layer.node().walk();
3563
3564            // Find the node that both contains the range and is larger than it.
3565            if !Self::goto_node_enclosing_range(&mut cursor, &range, true) {
3566                continue;
3567            }
3568
3569            let left_node = cursor.node();
3570            let mut layer_result = left_node;
3571
3572            // For an empty range, try to find another node immediately to the right of the range.
3573            if left_node.end_byte() == range.start {
3574                let mut right_node = None;
3575                while !cursor.goto_next_sibling() {
3576                    if !cursor.goto_parent() {
3577                        break;
3578                    }
3579                }
3580
3581                while cursor.node().start_byte() == range.start {
3582                    right_node = Some(cursor.node());
3583                    if !cursor.goto_first_child() {
3584                        break;
3585                    }
3586                }
3587
3588                // If there is a candidate node on both sides of the (empty) range, then
3589                // decide between the two by favoring a named node over an anonymous token.
3590                // If both nodes are the same in that regard, favor the right one.
3591                if let Some(right_node) = right_node
3592                    && (right_node.is_named() || !left_node.is_named())
3593                {
3594                    layer_result = right_node;
3595                }
3596            }
3597
3598            if let Some(previous_result) = &result
3599                && previous_result.byte_range().len() < layer_result.byte_range().len()
3600            {
3601                continue;
3602            }
3603            result = Some(layer_result);
3604        }
3605
3606        result
3607    }
3608
3609    /// Find the previous sibling syntax node at the given range.
3610    ///
3611    /// This function locates the syntax node that precedes the node containing
3612    /// the given range. It searches hierarchically by:
3613    /// 1. Finding the node that contains the given range
3614    /// 2. Looking for the previous sibling at the same tree level
3615    /// 3. If no sibling is found, moving up to parent levels and searching for siblings
3616    ///
3617    /// Returns `None` if there is no previous sibling at any ancestor level.
3618    pub fn syntax_prev_sibling<'a, T: ToOffset>(
3619        &'a self,
3620        range: Range<T>,
3621    ) -> Option<tree_sitter::Node<'a>> {
3622        let range = range.start.to_offset(self)..range.end.to_offset(self);
3623        let mut result: Option<tree_sitter::Node<'a>> = None;
3624
3625        for layer in self
3626            .syntax
3627            .layers_for_range(range.clone(), &self.text, true)
3628        {
3629            let mut cursor = layer.node().walk();
3630
3631            // Find the node that contains the range
3632            if !Self::goto_node_enclosing_range(&mut cursor, &range, false) {
3633                continue;
3634            }
3635
3636            // Look for the previous sibling, moving up ancestor levels if needed
3637            loop {
3638                if cursor.goto_previous_sibling() {
3639                    let layer_result = cursor.node();
3640
3641                    if let Some(previous_result) = &result {
3642                        if previous_result.byte_range().end < layer_result.byte_range().end {
3643                            continue;
3644                        }
3645                    }
3646                    result = Some(layer_result);
3647                    break;
3648                }
3649
3650                // No sibling found at this level, try moving up to parent
3651                if !cursor.goto_parent() {
3652                    break;
3653                }
3654            }
3655        }
3656
3657        result
3658    }
3659
3660    /// Find the next sibling syntax node at the given range.
3661    ///
3662    /// This function locates the syntax node that follows the node containing
3663    /// the given range. It searches hierarchically by:
3664    /// 1. Finding the node that contains the given range
3665    /// 2. Looking for the next sibling at the same tree level
3666    /// 3. If no sibling is found, moving up to parent levels and searching for siblings
3667    ///
3668    /// Returns `None` if there is no next sibling at any ancestor level.
3669    pub fn syntax_next_sibling<'a, T: ToOffset>(
3670        &'a self,
3671        range: Range<T>,
3672    ) -> Option<tree_sitter::Node<'a>> {
3673        let range = range.start.to_offset(self)..range.end.to_offset(self);
3674        let mut result: Option<tree_sitter::Node<'a>> = None;
3675
3676        for layer in self
3677            .syntax
3678            .layers_for_range(range.clone(), &self.text, true)
3679        {
3680            let mut cursor = layer.node().walk();
3681
3682            // Find the node that contains the range
3683            if !Self::goto_node_enclosing_range(&mut cursor, &range, false) {
3684                continue;
3685            }
3686
3687            // Look for the next sibling, moving up ancestor levels if needed
3688            loop {
3689                if cursor.goto_next_sibling() {
3690                    let layer_result = cursor.node();
3691
3692                    if let Some(previous_result) = &result {
3693                        if previous_result.byte_range().start > layer_result.byte_range().start {
3694                            continue;
3695                        }
3696                    }
3697                    result = Some(layer_result);
3698                    break;
3699                }
3700
3701                // No sibling found at this level, try moving up to parent
3702                if !cursor.goto_parent() {
3703                    break;
3704                }
3705            }
3706        }
3707
3708        result
3709    }
3710
3711    /// Returns the root syntax node within the given row
3712    pub fn syntax_root_ancestor(&self, position: Anchor) -> Option<tree_sitter::Node<'_>> {
3713        let start_offset = position.to_offset(self);
3714
3715        let row = self.summary_for_anchor::<text::PointUtf16>(&position).row as usize;
3716
3717        let layer = self
3718            .syntax
3719            .layers_for_range(start_offset..start_offset, &self.text, true)
3720            .next()?;
3721
3722        let mut cursor = layer.node().walk();
3723
3724        // Descend to the first leaf that touches the start of the range.
3725        while cursor.goto_first_child_for_byte(start_offset).is_some() {
3726            if cursor.node().end_byte() == start_offset {
3727                cursor.goto_next_sibling();
3728            }
3729        }
3730
3731        // Ascend to the root node within the same row.
3732        while cursor.goto_parent() {
3733            if cursor.node().start_position().row != row {
3734                break;
3735            }
3736        }
3737
3738        Some(cursor.node())
3739    }
3740
3741    /// Returns the outline for the buffer.
3742    ///
3743    /// This method allows passing an optional [`SyntaxTheme`] to
3744    /// syntax-highlight the returned symbols.
3745    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Outline<Anchor> {
3746        Outline::new(self.outline_items_containing(0..self.len(), true, theme))
3747    }
3748
3749    /// Returns all the symbols that contain the given position.
3750    ///
3751    /// This method allows passing an optional [`SyntaxTheme`] to
3752    /// syntax-highlight the returned symbols.
3753    pub fn symbols_containing<T: ToOffset>(
3754        &self,
3755        position: T,
3756        theme: Option<&SyntaxTheme>,
3757    ) -> Vec<OutlineItem<Anchor>> {
3758        let position = position.to_offset(self);
3759        let start = self.clip_offset(position.saturating_sub(1), Bias::Left);
3760        let end = self.clip_offset(position + 1, Bias::Right);
3761        let mut items = self.outline_items_containing(start..end, false, theme);
3762        let mut prev_depth = None;
3763        items.retain(|item| {
3764            let result = prev_depth.is_none_or(|prev_depth| item.depth > prev_depth);
3765            prev_depth = Some(item.depth);
3766            result
3767        });
3768        items
3769    }
3770
3771    pub fn outline_range_containing<T: ToOffset>(&self, range: Range<T>) -> Option<Range<Point>> {
3772        let range = range.to_offset(self);
3773        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3774            grammar.outline_config.as_ref().map(|c| &c.query)
3775        });
3776        let configs = matches
3777            .grammars()
3778            .iter()
3779            .map(|g| g.outline_config.as_ref().unwrap())
3780            .collect::<Vec<_>>();
3781
3782        while let Some(mat) = matches.peek() {
3783            let config = &configs[mat.grammar_index];
3784            let containing_item_node = maybe!({
3785                let item_node = mat.captures.iter().find_map(|cap| {
3786                    if cap.index == config.item_capture_ix {
3787                        Some(cap.node)
3788                    } else {
3789                        None
3790                    }
3791                })?;
3792
3793                let item_byte_range = item_node.byte_range();
3794                if item_byte_range.end < range.start || item_byte_range.start > range.end {
3795                    None
3796                } else {
3797                    Some(item_node)
3798                }
3799            });
3800
3801            if let Some(item_node) = containing_item_node {
3802                return Some(
3803                    Point::from_ts_point(item_node.start_position())
3804                        ..Point::from_ts_point(item_node.end_position()),
3805                );
3806            }
3807
3808            matches.advance();
3809        }
3810        None
3811    }
3812
3813    pub fn outline_items_containing<T: ToOffset>(
3814        &self,
3815        range: Range<T>,
3816        include_extra_context: bool,
3817        theme: Option<&SyntaxTheme>,
3818    ) -> Vec<OutlineItem<Anchor>> {
3819        let range = range.to_offset(self);
3820        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3821            grammar.outline_config.as_ref().map(|c| &c.query)
3822        });
3823
3824        let mut items = Vec::new();
3825        let mut annotation_row_ranges: Vec<Range<u32>> = Vec::new();
3826        while let Some(mat) = matches.peek() {
3827            let config = matches.grammars()[mat.grammar_index]
3828                .outline_config
3829                .as_ref()
3830                .unwrap();
3831            if let Some(item) =
3832                self.next_outline_item(config, &mat, &range, include_extra_context, theme)
3833            {
3834                items.push(item);
3835            } else if let Some(capture) = mat
3836                .captures
3837                .iter()
3838                .find(|capture| Some(capture.index) == config.annotation_capture_ix)
3839            {
3840                let capture_range = capture.node.start_position()..capture.node.end_position();
3841                let mut capture_row_range =
3842                    capture_range.start.row as u32..capture_range.end.row as u32;
3843                if capture_range.end.row > capture_range.start.row && capture_range.end.column == 0
3844                {
3845                    capture_row_range.end -= 1;
3846                }
3847                if let Some(last_row_range) = annotation_row_ranges.last_mut() {
3848                    if last_row_range.end >= capture_row_range.start.saturating_sub(1) {
3849                        last_row_range.end = capture_row_range.end;
3850                    } else {
3851                        annotation_row_ranges.push(capture_row_range);
3852                    }
3853                } else {
3854                    annotation_row_ranges.push(capture_row_range);
3855                }
3856            }
3857            matches.advance();
3858        }
3859
3860        items.sort_by_key(|item| (item.range.start, Reverse(item.range.end)));
3861
3862        // Assign depths based on containment relationships and convert to anchors.
3863        let mut item_ends_stack = Vec::<Point>::new();
3864        let mut anchor_items = Vec::new();
3865        let mut annotation_row_ranges = annotation_row_ranges.into_iter().peekable();
3866        for item in items {
3867            while let Some(last_end) = item_ends_stack.last().copied() {
3868                if last_end < item.range.end {
3869                    item_ends_stack.pop();
3870                } else {
3871                    break;
3872                }
3873            }
3874
3875            let mut annotation_row_range = None;
3876            while let Some(next_annotation_row_range) = annotation_row_ranges.peek() {
3877                let row_preceding_item = item.range.start.row.saturating_sub(1);
3878                if next_annotation_row_range.end < row_preceding_item {
3879                    annotation_row_ranges.next();
3880                } else {
3881                    if next_annotation_row_range.end == row_preceding_item {
3882                        annotation_row_range = Some(next_annotation_row_range.clone());
3883                        annotation_row_ranges.next();
3884                    }
3885                    break;
3886                }
3887            }
3888
3889            anchor_items.push(OutlineItem {
3890                depth: item_ends_stack.len(),
3891                range: self.anchor_after(item.range.start)..self.anchor_before(item.range.end),
3892                text: item.text,
3893                highlight_ranges: item.highlight_ranges,
3894                name_ranges: item.name_ranges,
3895                body_range: item
3896                    .body_range
3897                    .map(|r| self.anchor_after(r.start)..self.anchor_before(r.end)),
3898                annotation_range: annotation_row_range.map(|annotation_range| {
3899                    self.anchor_after(Point::new(annotation_range.start, 0))
3900                        ..self.anchor_before(Point::new(
3901                            annotation_range.end,
3902                            self.line_len(annotation_range.end),
3903                        ))
3904                }),
3905            });
3906            item_ends_stack.push(item.range.end);
3907        }
3908
3909        anchor_items
3910    }
3911
3912    fn next_outline_item(
3913        &self,
3914        config: &OutlineConfig,
3915        mat: &SyntaxMapMatch,
3916        range: &Range<usize>,
3917        include_extra_context: bool,
3918        theme: Option<&SyntaxTheme>,
3919    ) -> Option<OutlineItem<Point>> {
3920        let item_node = mat.captures.iter().find_map(|cap| {
3921            if cap.index == config.item_capture_ix {
3922                Some(cap.node)
3923            } else {
3924                None
3925            }
3926        })?;
3927
3928        let item_byte_range = item_node.byte_range();
3929        if item_byte_range.end < range.start || item_byte_range.start > range.end {
3930            return None;
3931        }
3932        let item_point_range = Point::from_ts_point(item_node.start_position())
3933            ..Point::from_ts_point(item_node.end_position());
3934
3935        let mut open_point = None;
3936        let mut close_point = None;
3937
3938        let mut buffer_ranges = Vec::new();
3939        let mut add_to_buffer_ranges = |node: tree_sitter::Node, node_is_name| {
3940            let mut range = node.start_byte()..node.end_byte();
3941            let start = node.start_position();
3942            if node.end_position().row > start.row {
3943                range.end = range.start + self.line_len(start.row as u32) as usize - start.column;
3944            }
3945
3946            if !range.is_empty() {
3947                buffer_ranges.push((range, node_is_name));
3948            }
3949        };
3950
3951        for capture in mat.captures {
3952            if capture.index == config.name_capture_ix {
3953                add_to_buffer_ranges(capture.node, true);
3954            } else if Some(capture.index) == config.context_capture_ix
3955                || (Some(capture.index) == config.extra_context_capture_ix && include_extra_context)
3956            {
3957                add_to_buffer_ranges(capture.node, false);
3958            } else {
3959                if Some(capture.index) == config.open_capture_ix {
3960                    open_point = Some(Point::from_ts_point(capture.node.end_position()));
3961                } else if Some(capture.index) == config.close_capture_ix {
3962                    close_point = Some(Point::from_ts_point(capture.node.start_position()));
3963                }
3964            }
3965        }
3966
3967        if buffer_ranges.is_empty() {
3968            return None;
3969        }
3970
3971        let mut text = String::new();
3972        let mut highlight_ranges = Vec::new();
3973        let mut name_ranges = Vec::new();
3974        let mut chunks = self.chunks(
3975            buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
3976            true,
3977        );
3978        let mut last_buffer_range_end = 0;
3979        for (buffer_range, is_name) in buffer_ranges {
3980            let space_added = !text.is_empty() && buffer_range.start > last_buffer_range_end;
3981            if space_added {
3982                text.push(' ');
3983            }
3984            let before_append_len = text.len();
3985            let mut offset = buffer_range.start;
3986            chunks.seek(buffer_range.clone());
3987            for mut chunk in chunks.by_ref() {
3988                if chunk.text.len() > buffer_range.end - offset {
3989                    chunk.text = &chunk.text[0..(buffer_range.end - offset)];
3990                    offset = buffer_range.end;
3991                } else {
3992                    offset += chunk.text.len();
3993                }
3994                let style = chunk
3995                    .syntax_highlight_id
3996                    .zip(theme)
3997                    .and_then(|(highlight, theme)| highlight.style(theme));
3998                if let Some(style) = style {
3999                    let start = text.len();
4000                    let end = start + chunk.text.len();
4001                    highlight_ranges.push((start..end, style));
4002                }
4003                text.push_str(chunk.text);
4004                if offset >= buffer_range.end {
4005                    break;
4006                }
4007            }
4008            if is_name {
4009                let after_append_len = text.len();
4010                let start = if space_added && !name_ranges.is_empty() {
4011                    before_append_len - 1
4012                } else {
4013                    before_append_len
4014                };
4015                name_ranges.push(start..after_append_len);
4016            }
4017            last_buffer_range_end = buffer_range.end;
4018        }
4019
4020        Some(OutlineItem {
4021            depth: 0, // We'll calculate the depth later
4022            range: item_point_range,
4023            text,
4024            highlight_ranges,
4025            name_ranges,
4026            body_range: open_point.zip(close_point).map(|(start, end)| start..end),
4027            annotation_range: None,
4028        })
4029    }
4030
4031    pub fn function_body_fold_ranges<T: ToOffset>(
4032        &self,
4033        within: Range<T>,
4034    ) -> impl Iterator<Item = Range<usize>> + '_ {
4035        self.text_object_ranges(within, TreeSitterOptions::default())
4036            .filter_map(|(range, obj)| (obj == TextObject::InsideFunction).then_some(range))
4037    }
4038
4039    /// For each grammar in the language, runs the provided
4040    /// [`tree_sitter::Query`] against the given range.
4041    pub fn matches(
4042        &self,
4043        range: Range<usize>,
4044        query: fn(&Grammar) -> Option<&tree_sitter::Query>,
4045    ) -> SyntaxMapMatches<'_> {
4046        self.syntax.matches(range, self, query)
4047    }
4048
4049    pub fn all_bracket_ranges(
4050        &self,
4051        range: Range<usize>,
4052    ) -> impl Iterator<Item = BracketMatch> + '_ {
4053        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
4054            grammar.brackets_config.as_ref().map(|c| &c.query)
4055        });
4056        let configs = matches
4057            .grammars()
4058            .iter()
4059            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
4060            .collect::<Vec<_>>();
4061
4062        iter::from_fn(move || {
4063            while let Some(mat) = matches.peek() {
4064                let mut open = None;
4065                let mut close = None;
4066                let config = &configs[mat.grammar_index];
4067                let pattern = &config.patterns[mat.pattern_index];
4068                for capture in mat.captures {
4069                    if capture.index == config.open_capture_ix {
4070                        open = Some(capture.node.byte_range());
4071                    } else if capture.index == config.close_capture_ix {
4072                        close = Some(capture.node.byte_range());
4073                    }
4074                }
4075
4076                matches.advance();
4077
4078                let Some((open_range, close_range)) = open.zip(close) else {
4079                    continue;
4080                };
4081
4082                let bracket_range = open_range.start..=close_range.end;
4083                if !bracket_range.overlaps(&range) {
4084                    continue;
4085                }
4086
4087                return Some(BracketMatch {
4088                    open_range,
4089                    close_range,
4090                    newline_only: pattern.newline_only,
4091                });
4092            }
4093            None
4094        })
4095    }
4096
4097    /// Returns bracket range pairs overlapping or adjacent to `range`
4098    pub fn bracket_ranges<T: ToOffset>(
4099        &self,
4100        range: Range<T>,
4101    ) -> impl Iterator<Item = BracketMatch> + '_ {
4102        // Find bracket pairs that *inclusively* contain the given range.
4103        let range = range.start.to_previous_offset(self)..range.end.to_next_offset(self);
4104        self.all_bracket_ranges(range)
4105            .filter(|pair| !pair.newline_only)
4106    }
4107
4108    pub fn debug_variables_query<T: ToOffset>(
4109        &self,
4110        range: Range<T>,
4111    ) -> impl Iterator<Item = (Range<usize>, DebuggerTextObject)> + '_ {
4112        let range = range.start.to_previous_offset(self)..range.end.to_next_offset(self);
4113
4114        let mut matches = self.syntax.matches_with_options(
4115            range.clone(),
4116            &self.text,
4117            TreeSitterOptions::default(),
4118            |grammar| grammar.debug_variables_config.as_ref().map(|c| &c.query),
4119        );
4120
4121        let configs = matches
4122            .grammars()
4123            .iter()
4124            .map(|grammar| grammar.debug_variables_config.as_ref())
4125            .collect::<Vec<_>>();
4126
4127        let mut captures = Vec::<(Range<usize>, DebuggerTextObject)>::new();
4128
4129        iter::from_fn(move || {
4130            loop {
4131                while let Some(capture) = captures.pop() {
4132                    if capture.0.overlaps(&range) {
4133                        return Some(capture);
4134                    }
4135                }
4136
4137                let mat = matches.peek()?;
4138
4139                let Some(config) = configs[mat.grammar_index].as_ref() else {
4140                    matches.advance();
4141                    continue;
4142                };
4143
4144                for capture in mat.captures {
4145                    let Some(ix) = config
4146                        .objects_by_capture_ix
4147                        .binary_search_by_key(&capture.index, |e| e.0)
4148                        .ok()
4149                    else {
4150                        continue;
4151                    };
4152                    let text_object = config.objects_by_capture_ix[ix].1;
4153                    let byte_range = capture.node.byte_range();
4154
4155                    let mut found = false;
4156                    for (range, existing) in captures.iter_mut() {
4157                        if existing == &text_object {
4158                            range.start = range.start.min(byte_range.start);
4159                            range.end = range.end.max(byte_range.end);
4160                            found = true;
4161                            break;
4162                        }
4163                    }
4164
4165                    if !found {
4166                        captures.push((byte_range, text_object));
4167                    }
4168                }
4169
4170                matches.advance();
4171            }
4172        })
4173    }
4174
4175    pub fn text_object_ranges<T: ToOffset>(
4176        &self,
4177        range: Range<T>,
4178        options: TreeSitterOptions,
4179    ) -> impl Iterator<Item = (Range<usize>, TextObject)> + '_ {
4180        let range =
4181            range.start.to_previous_offset(self)..self.len().min(range.end.to_next_offset(self));
4182
4183        let mut matches =
4184            self.syntax
4185                .matches_with_options(range.clone(), &self.text, options, |grammar| {
4186                    grammar.text_object_config.as_ref().map(|c| &c.query)
4187                });
4188
4189        let configs = matches
4190            .grammars()
4191            .iter()
4192            .map(|grammar| grammar.text_object_config.as_ref())
4193            .collect::<Vec<_>>();
4194
4195        let mut captures = Vec::<(Range<usize>, TextObject)>::new();
4196
4197        iter::from_fn(move || {
4198            loop {
4199                while let Some(capture) = captures.pop() {
4200                    if capture.0.overlaps(&range) {
4201                        return Some(capture);
4202                    }
4203                }
4204
4205                let mat = matches.peek()?;
4206
4207                let Some(config) = configs[mat.grammar_index].as_ref() else {
4208                    matches.advance();
4209                    continue;
4210                };
4211
4212                for capture in mat.captures {
4213                    let Some(ix) = config
4214                        .text_objects_by_capture_ix
4215                        .binary_search_by_key(&capture.index, |e| e.0)
4216                        .ok()
4217                    else {
4218                        continue;
4219                    };
4220                    let text_object = config.text_objects_by_capture_ix[ix].1;
4221                    let byte_range = capture.node.byte_range();
4222
4223                    let mut found = false;
4224                    for (range, existing) in captures.iter_mut() {
4225                        if existing == &text_object {
4226                            range.start = range.start.min(byte_range.start);
4227                            range.end = range.end.max(byte_range.end);
4228                            found = true;
4229                            break;
4230                        }
4231                    }
4232
4233                    if !found {
4234                        captures.push((byte_range, text_object));
4235                    }
4236                }
4237
4238                matches.advance();
4239            }
4240        })
4241    }
4242
4243    /// Returns enclosing bracket ranges containing the given range
4244    pub fn enclosing_bracket_ranges<T: ToOffset>(
4245        &self,
4246        range: Range<T>,
4247    ) -> impl Iterator<Item = BracketMatch> + '_ {
4248        let range = range.start.to_offset(self)..range.end.to_offset(self);
4249
4250        self.bracket_ranges(range.clone()).filter(move |pair| {
4251            pair.open_range.start <= range.start && pair.close_range.end >= range.end
4252        })
4253    }
4254
4255    /// Returns the smallest enclosing bracket ranges containing the given range or None if no brackets contain range
4256    ///
4257    /// Can optionally pass a range_filter to filter the ranges of brackets to consider
4258    pub fn innermost_enclosing_bracket_ranges<T: ToOffset>(
4259        &self,
4260        range: Range<T>,
4261        range_filter: Option<&dyn Fn(Range<usize>, Range<usize>) -> bool>,
4262    ) -> Option<(Range<usize>, Range<usize>)> {
4263        let range = range.start.to_offset(self)..range.end.to_offset(self);
4264
4265        // Get the ranges of the innermost pair of brackets.
4266        let mut result: Option<(Range<usize>, Range<usize>)> = None;
4267
4268        for pair in self.enclosing_bracket_ranges(range) {
4269            if let Some(range_filter) = range_filter
4270                && !range_filter(pair.open_range.clone(), pair.close_range.clone())
4271            {
4272                continue;
4273            }
4274
4275            let len = pair.close_range.end - pair.open_range.start;
4276
4277            if let Some((existing_open, existing_close)) = &result {
4278                let existing_len = existing_close.end - existing_open.start;
4279                if len > existing_len {
4280                    continue;
4281                }
4282            }
4283
4284            result = Some((pair.open_range, pair.close_range));
4285        }
4286
4287        result
4288    }
4289
4290    /// Returns anchor ranges for any matches of the redaction query.
4291    /// The buffer can be associated with multiple languages, and the redaction query associated with each
4292    /// will be run on the relevant section of the buffer.
4293    pub fn redacted_ranges<T: ToOffset>(
4294        &self,
4295        range: Range<T>,
4296    ) -> impl Iterator<Item = Range<usize>> + '_ {
4297        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
4298        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4299            grammar
4300                .redactions_config
4301                .as_ref()
4302                .map(|config| &config.query)
4303        });
4304
4305        let configs = syntax_matches
4306            .grammars()
4307            .iter()
4308            .map(|grammar| grammar.redactions_config.as_ref())
4309            .collect::<Vec<_>>();
4310
4311        iter::from_fn(move || {
4312            let redacted_range = syntax_matches
4313                .peek()
4314                .and_then(|mat| {
4315                    configs[mat.grammar_index].and_then(|config| {
4316                        mat.captures
4317                            .iter()
4318                            .find(|capture| capture.index == config.redaction_capture_ix)
4319                    })
4320                })
4321                .map(|mat| mat.node.byte_range());
4322            syntax_matches.advance();
4323            redacted_range
4324        })
4325    }
4326
4327    pub fn injections_intersecting_range<T: ToOffset>(
4328        &self,
4329        range: Range<T>,
4330    ) -> impl Iterator<Item = (Range<usize>, &Arc<Language>)> + '_ {
4331        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
4332
4333        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4334            grammar
4335                .injection_config
4336                .as_ref()
4337                .map(|config| &config.query)
4338        });
4339
4340        let configs = syntax_matches
4341            .grammars()
4342            .iter()
4343            .map(|grammar| grammar.injection_config.as_ref())
4344            .collect::<Vec<_>>();
4345
4346        iter::from_fn(move || {
4347            let ranges = syntax_matches.peek().and_then(|mat| {
4348                let config = &configs[mat.grammar_index]?;
4349                let content_capture_range = mat.captures.iter().find_map(|capture| {
4350                    if capture.index == config.content_capture_ix {
4351                        Some(capture.node.byte_range())
4352                    } else {
4353                        None
4354                    }
4355                })?;
4356                let language = self.language_at(content_capture_range.start)?;
4357                Some((content_capture_range, language))
4358            });
4359            syntax_matches.advance();
4360            ranges
4361        })
4362    }
4363
4364    pub fn runnable_ranges(
4365        &self,
4366        offset_range: Range<usize>,
4367    ) -> impl Iterator<Item = RunnableRange> + '_ {
4368        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
4369            grammar.runnable_config.as_ref().map(|config| &config.query)
4370        });
4371
4372        let test_configs = syntax_matches
4373            .grammars()
4374            .iter()
4375            .map(|grammar| grammar.runnable_config.as_ref())
4376            .collect::<Vec<_>>();
4377
4378        iter::from_fn(move || {
4379            loop {
4380                let mat = syntax_matches.peek()?;
4381
4382                let test_range = test_configs[mat.grammar_index].and_then(|test_configs| {
4383                    let mut run_range = None;
4384                    let full_range = mat.captures.iter().fold(
4385                        Range {
4386                            start: usize::MAX,
4387                            end: 0,
4388                        },
4389                        |mut acc, next| {
4390                            let byte_range = next.node.byte_range();
4391                            if acc.start > byte_range.start {
4392                                acc.start = byte_range.start;
4393                            }
4394                            if acc.end < byte_range.end {
4395                                acc.end = byte_range.end;
4396                            }
4397                            acc
4398                        },
4399                    );
4400                    if full_range.start > full_range.end {
4401                        // We did not find a full spanning range of this match.
4402                        return None;
4403                    }
4404                    let extra_captures: SmallVec<[_; 1]> =
4405                        SmallVec::from_iter(mat.captures.iter().filter_map(|capture| {
4406                            test_configs
4407                                .extra_captures
4408                                .get(capture.index as usize)
4409                                .cloned()
4410                                .and_then(|tag_name| match tag_name {
4411                                    RunnableCapture::Named(name) => {
4412                                        Some((capture.node.byte_range(), name))
4413                                    }
4414                                    RunnableCapture::Run => {
4415                                        let _ = run_range.insert(capture.node.byte_range());
4416                                        None
4417                                    }
4418                                })
4419                        }));
4420                    let run_range = run_range?;
4421                    let tags = test_configs
4422                        .query
4423                        .property_settings(mat.pattern_index)
4424                        .iter()
4425                        .filter_map(|property| {
4426                            if *property.key == *"tag" {
4427                                property
4428                                    .value
4429                                    .as_ref()
4430                                    .map(|value| RunnableTag(value.to_string().into()))
4431                            } else {
4432                                None
4433                            }
4434                        })
4435                        .collect();
4436                    let extra_captures = extra_captures
4437                        .into_iter()
4438                        .map(|(range, name)| {
4439                            (
4440                                name.to_string(),
4441                                self.text_for_range(range).collect::<String>(),
4442                            )
4443                        })
4444                        .collect();
4445                    // All tags should have the same range.
4446                    Some(RunnableRange {
4447                        run_range,
4448                        full_range,
4449                        runnable: Runnable {
4450                            tags,
4451                            language: mat.language,
4452                            buffer: self.remote_id(),
4453                        },
4454                        extra_captures,
4455                        buffer_id: self.remote_id(),
4456                    })
4457                });
4458
4459                syntax_matches.advance();
4460                if test_range.is_some() {
4461                    // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
4462                    // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
4463                    return test_range;
4464                }
4465            }
4466        })
4467    }
4468
4469    /// Returns selections for remote peers intersecting the given range.
4470    #[allow(clippy::type_complexity)]
4471    pub fn selections_in_range(
4472        &self,
4473        range: Range<Anchor>,
4474        include_local: bool,
4475    ) -> impl Iterator<
4476        Item = (
4477            ReplicaId,
4478            bool,
4479            CursorShape,
4480            impl Iterator<Item = &Selection<Anchor>> + '_,
4481        ),
4482    > + '_ {
4483        self.remote_selections
4484            .iter()
4485            .filter(move |(replica_id, set)| {
4486                (include_local || **replica_id != self.text.replica_id())
4487                    && !set.selections.is_empty()
4488            })
4489            .map(move |(replica_id, set)| {
4490                let start_ix = match set.selections.binary_search_by(|probe| {
4491                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
4492                }) {
4493                    Ok(ix) | Err(ix) => ix,
4494                };
4495                let end_ix = match set.selections.binary_search_by(|probe| {
4496                    probe.start.cmp(&range.end, self).then(Ordering::Less)
4497                }) {
4498                    Ok(ix) | Err(ix) => ix,
4499                };
4500
4501                (
4502                    *replica_id,
4503                    set.line_mode,
4504                    set.cursor_shape,
4505                    set.selections[start_ix..end_ix].iter(),
4506                )
4507            })
4508    }
4509
4510    /// Returns if the buffer contains any diagnostics.
4511    pub fn has_diagnostics(&self) -> bool {
4512        !self.diagnostics.is_empty()
4513    }
4514
4515    /// Returns all the diagnostics intersecting the given range.
4516    pub fn diagnostics_in_range<'a, T, O>(
4517        &'a self,
4518        search_range: Range<T>,
4519        reversed: bool,
4520    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
4521    where
4522        T: 'a + Clone + ToOffset,
4523        O: 'a + FromAnchor,
4524    {
4525        let mut iterators: Vec<_> = self
4526            .diagnostics
4527            .iter()
4528            .map(|(_, collection)| {
4529                collection
4530                    .range::<T, text::Anchor>(search_range.clone(), self, true, reversed)
4531                    .peekable()
4532            })
4533            .collect();
4534
4535        std::iter::from_fn(move || {
4536            let (next_ix, _) = iterators
4537                .iter_mut()
4538                .enumerate()
4539                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
4540                .min_by(|(_, a), (_, b)| {
4541                    let cmp = a
4542                        .range
4543                        .start
4544                        .cmp(&b.range.start, self)
4545                        // when range is equal, sort by diagnostic severity
4546                        .then(a.diagnostic.severity.cmp(&b.diagnostic.severity))
4547                        // and stabilize order with group_id
4548                        .then(a.diagnostic.group_id.cmp(&b.diagnostic.group_id));
4549                    if reversed { cmp.reverse() } else { cmp }
4550                })?;
4551            iterators[next_ix]
4552                .next()
4553                .map(|DiagnosticEntry { range, diagnostic }| DiagnosticEntry {
4554                    diagnostic,
4555                    range: FromAnchor::from_anchor(&range.start, self)
4556                        ..FromAnchor::from_anchor(&range.end, self),
4557                })
4558        })
4559    }
4560
4561    /// Raw access to the diagnostic sets. Typically `diagnostic_groups` or `diagnostic_group`
4562    /// should be used instead.
4563    pub fn diagnostic_sets(&self) -> &SmallVec<[(LanguageServerId, DiagnosticSet); 2]> {
4564        &self.diagnostics
4565    }
4566
4567    /// Returns all the diagnostic groups associated with the given
4568    /// language server ID. If no language server ID is provided,
4569    /// all diagnostics groups are returned.
4570    pub fn diagnostic_groups(
4571        &self,
4572        language_server_id: Option<LanguageServerId>,
4573    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
4574        let mut groups = Vec::new();
4575
4576        if let Some(language_server_id) = language_server_id {
4577            if let Ok(ix) = self
4578                .diagnostics
4579                .binary_search_by_key(&language_server_id, |e| e.0)
4580            {
4581                self.diagnostics[ix]
4582                    .1
4583                    .groups(language_server_id, &mut groups, self);
4584            }
4585        } else {
4586            for (language_server_id, diagnostics) in self.diagnostics.iter() {
4587                diagnostics.groups(*language_server_id, &mut groups, self);
4588            }
4589        }
4590
4591        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
4592            let a_start = &group_a.entries[group_a.primary_ix].range.start;
4593            let b_start = &group_b.entries[group_b.primary_ix].range.start;
4594            a_start.cmp(b_start, self).then_with(|| id_a.cmp(id_b))
4595        });
4596
4597        groups
4598    }
4599
4600    /// Returns an iterator over the diagnostics for the given group.
4601    pub fn diagnostic_group<O>(
4602        &self,
4603        group_id: usize,
4604    ) -> impl Iterator<Item = DiagnosticEntry<O>> + '_
4605    where
4606        O: FromAnchor + 'static,
4607    {
4608        self.diagnostics
4609            .iter()
4610            .flat_map(move |(_, set)| set.group(group_id, self))
4611    }
4612
4613    /// An integer version number that accounts for all updates besides
4614    /// the buffer's text itself (which is versioned via a version vector).
4615    pub fn non_text_state_update_count(&self) -> usize {
4616        self.non_text_state_update_count
4617    }
4618
4619    /// An integer version that changes when the buffer's syntax changes.
4620    pub fn syntax_update_count(&self) -> usize {
4621        self.syntax.update_count()
4622    }
4623
4624    /// Returns a snapshot of underlying file.
4625    pub fn file(&self) -> Option<&Arc<dyn File>> {
4626        self.file.as_ref()
4627    }
4628
4629    /// Resolves the file path (relative to the worktree root) associated with the underlying file.
4630    pub fn resolve_file_path(&self, cx: &App, include_root: bool) -> Option<PathBuf> {
4631        if let Some(file) = self.file() {
4632            if file.path().file_name().is_none() || include_root {
4633                Some(file.full_path(cx))
4634            } else {
4635                Some(file.path().to_path_buf())
4636            }
4637        } else {
4638            None
4639        }
4640    }
4641
4642    pub fn words_in_range(&self, query: WordsQuery) -> BTreeMap<String, Range<Anchor>> {
4643        let query_str = query.fuzzy_contents;
4644        if query_str.is_some_and(|query| query.is_empty()) {
4645            return BTreeMap::default();
4646        }
4647
4648        let classifier = CharClassifier::new(self.language.clone().map(|language| LanguageScope {
4649            language,
4650            override_id: None,
4651        }));
4652
4653        let mut query_ix = 0;
4654        let query_chars = query_str.map(|query| query.chars().collect::<Vec<_>>());
4655        let query_len = query_chars.as_ref().map_or(0, |query| query.len());
4656
4657        let mut words = BTreeMap::default();
4658        let mut current_word_start_ix = None;
4659        let mut chunk_ix = query.range.start;
4660        for chunk in self.chunks(query.range, false) {
4661            for (i, c) in chunk.text.char_indices() {
4662                let ix = chunk_ix + i;
4663                if classifier.is_word(c) {
4664                    if current_word_start_ix.is_none() {
4665                        current_word_start_ix = Some(ix);
4666                    }
4667
4668                    if let Some(query_chars) = &query_chars
4669                        && query_ix < query_len
4670                        && c.to_lowercase().eq(query_chars[query_ix].to_lowercase())
4671                    {
4672                        query_ix += 1;
4673                    }
4674                    continue;
4675                } else if let Some(word_start) = current_word_start_ix.take()
4676                    && query_ix == query_len
4677                {
4678                    let word_range = self.anchor_before(word_start)..self.anchor_after(ix);
4679                    let mut word_text = self.text_for_range(word_start..ix).peekable();
4680                    let first_char = word_text
4681                        .peek()
4682                        .and_then(|first_chunk| first_chunk.chars().next());
4683                    // Skip empty and "words" starting with digits as a heuristic to reduce useless completions
4684                    if !query.skip_digits
4685                        || first_char.is_none_or(|first_char| !first_char.is_digit(10))
4686                    {
4687                        words.insert(word_text.collect(), word_range);
4688                    }
4689                }
4690                query_ix = 0;
4691            }
4692            chunk_ix += chunk.text.len();
4693        }
4694
4695        words
4696    }
4697}
4698
4699pub struct WordsQuery<'a> {
4700    /// Only returns words with all chars from the fuzzy string in them.
4701    pub fuzzy_contents: Option<&'a str>,
4702    /// Skips words that start with a digit.
4703    pub skip_digits: bool,
4704    /// Buffer offset range, to look for words.
4705    pub range: Range<usize>,
4706}
4707
4708fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
4709    indent_size_for_text(text.chars_at(Point::new(row, 0)))
4710}
4711
4712fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
4713    let mut result = IndentSize::spaces(0);
4714    for c in text {
4715        let kind = match c {
4716            ' ' => IndentKind::Space,
4717            '\t' => IndentKind::Tab,
4718            _ => break,
4719        };
4720        if result.len == 0 {
4721            result.kind = kind;
4722        }
4723        result.len += 1;
4724    }
4725    result
4726}
4727
4728impl Clone for BufferSnapshot {
4729    fn clone(&self) -> Self {
4730        Self {
4731            text: self.text.clone(),
4732            syntax: self.syntax.clone(),
4733            file: self.file.clone(),
4734            remote_selections: self.remote_selections.clone(),
4735            diagnostics: self.diagnostics.clone(),
4736            language: self.language.clone(),
4737            non_text_state_update_count: self.non_text_state_update_count,
4738        }
4739    }
4740}
4741
4742impl Deref for BufferSnapshot {
4743    type Target = text::BufferSnapshot;
4744
4745    fn deref(&self) -> &Self::Target {
4746        &self.text
4747    }
4748}
4749
4750unsafe impl Send for BufferChunks<'_> {}
4751
4752impl<'a> BufferChunks<'a> {
4753    pub(crate) fn new(
4754        text: &'a Rope,
4755        range: Range<usize>,
4756        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
4757        diagnostics: bool,
4758        buffer_snapshot: Option<&'a BufferSnapshot>,
4759    ) -> Self {
4760        let mut highlights = None;
4761        if let Some((captures, highlight_maps)) = syntax {
4762            highlights = Some(BufferChunkHighlights {
4763                captures,
4764                next_capture: None,
4765                stack: Default::default(),
4766                highlight_maps,
4767            })
4768        }
4769
4770        let diagnostic_endpoints = diagnostics.then(|| Vec::new().into_iter().peekable());
4771        let chunks = text.chunks_in_range(range.clone());
4772
4773        let mut this = BufferChunks {
4774            range,
4775            buffer_snapshot,
4776            chunks,
4777            diagnostic_endpoints,
4778            error_depth: 0,
4779            warning_depth: 0,
4780            information_depth: 0,
4781            hint_depth: 0,
4782            unnecessary_depth: 0,
4783            underline: true,
4784            highlights,
4785        };
4786        this.initialize_diagnostic_endpoints();
4787        this
4788    }
4789
4790    /// Seeks to the given byte offset in the buffer.
4791    pub fn seek(&mut self, range: Range<usize>) {
4792        let old_range = std::mem::replace(&mut self.range, range.clone());
4793        self.chunks.set_range(self.range.clone());
4794        if let Some(highlights) = self.highlights.as_mut() {
4795            if old_range.start <= self.range.start && old_range.end >= self.range.end {
4796                // Reuse existing highlights stack, as the new range is a subrange of the old one.
4797                highlights
4798                    .stack
4799                    .retain(|(end_offset, _)| *end_offset > range.start);
4800                if let Some(capture) = &highlights.next_capture
4801                    && range.start >= capture.node.start_byte()
4802                {
4803                    let next_capture_end = capture.node.end_byte();
4804                    if range.start < next_capture_end {
4805                        highlights.stack.push((
4806                            next_capture_end,
4807                            highlights.highlight_maps[capture.grammar_index].get(capture.index),
4808                        ));
4809                    }
4810                    highlights.next_capture.take();
4811                }
4812            } else if let Some(snapshot) = self.buffer_snapshot {
4813                let (captures, highlight_maps) = snapshot.get_highlights(self.range.clone());
4814                *highlights = BufferChunkHighlights {
4815                    captures,
4816                    next_capture: None,
4817                    stack: Default::default(),
4818                    highlight_maps,
4819                };
4820            } else {
4821                // We cannot obtain new highlights for a language-aware buffer iterator, as we don't have a buffer snapshot.
4822                // Seeking such BufferChunks is not supported.
4823                debug_assert!(
4824                    false,
4825                    "Attempted to seek on a language-aware buffer iterator without associated buffer snapshot"
4826                );
4827            }
4828
4829            highlights.captures.set_byte_range(self.range.clone());
4830            self.initialize_diagnostic_endpoints();
4831        }
4832    }
4833
4834    fn initialize_diagnostic_endpoints(&mut self) {
4835        if let Some(diagnostics) = self.diagnostic_endpoints.as_mut()
4836            && let Some(buffer) = self.buffer_snapshot
4837        {
4838            let mut diagnostic_endpoints = Vec::new();
4839            for entry in buffer.diagnostics_in_range::<_, usize>(self.range.clone(), false) {
4840                diagnostic_endpoints.push(DiagnosticEndpoint {
4841                    offset: entry.range.start,
4842                    is_start: true,
4843                    severity: entry.diagnostic.severity,
4844                    is_unnecessary: entry.diagnostic.is_unnecessary,
4845                    underline: entry.diagnostic.underline,
4846                });
4847                diagnostic_endpoints.push(DiagnosticEndpoint {
4848                    offset: entry.range.end,
4849                    is_start: false,
4850                    severity: entry.diagnostic.severity,
4851                    is_unnecessary: entry.diagnostic.is_unnecessary,
4852                    underline: entry.diagnostic.underline,
4853                });
4854            }
4855            diagnostic_endpoints
4856                .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
4857            *diagnostics = diagnostic_endpoints.into_iter().peekable();
4858            self.hint_depth = 0;
4859            self.error_depth = 0;
4860            self.warning_depth = 0;
4861            self.information_depth = 0;
4862        }
4863    }
4864
4865    /// The current byte offset in the buffer.
4866    pub fn offset(&self) -> usize {
4867        self.range.start
4868    }
4869
4870    pub fn range(&self) -> Range<usize> {
4871        self.range.clone()
4872    }
4873
4874    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
4875        let depth = match endpoint.severity {
4876            DiagnosticSeverity::ERROR => &mut self.error_depth,
4877            DiagnosticSeverity::WARNING => &mut self.warning_depth,
4878            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
4879            DiagnosticSeverity::HINT => &mut self.hint_depth,
4880            _ => return,
4881        };
4882        if endpoint.is_start {
4883            *depth += 1;
4884        } else {
4885            *depth -= 1;
4886        }
4887
4888        if endpoint.is_unnecessary {
4889            if endpoint.is_start {
4890                self.unnecessary_depth += 1;
4891            } else {
4892                self.unnecessary_depth -= 1;
4893            }
4894        }
4895    }
4896
4897    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
4898        if self.error_depth > 0 {
4899            Some(DiagnosticSeverity::ERROR)
4900        } else if self.warning_depth > 0 {
4901            Some(DiagnosticSeverity::WARNING)
4902        } else if self.information_depth > 0 {
4903            Some(DiagnosticSeverity::INFORMATION)
4904        } else if self.hint_depth > 0 {
4905            Some(DiagnosticSeverity::HINT)
4906        } else {
4907            None
4908        }
4909    }
4910
4911    fn current_code_is_unnecessary(&self) -> bool {
4912        self.unnecessary_depth > 0
4913    }
4914}
4915
4916impl<'a> Iterator for BufferChunks<'a> {
4917    type Item = Chunk<'a>;
4918
4919    fn next(&mut self) -> Option<Self::Item> {
4920        let mut next_capture_start = usize::MAX;
4921        let mut next_diagnostic_endpoint = usize::MAX;
4922
4923        if let Some(highlights) = self.highlights.as_mut() {
4924            while let Some((parent_capture_end, _)) = highlights.stack.last() {
4925                if *parent_capture_end <= self.range.start {
4926                    highlights.stack.pop();
4927                } else {
4928                    break;
4929                }
4930            }
4931
4932            if highlights.next_capture.is_none() {
4933                highlights.next_capture = highlights.captures.next();
4934            }
4935
4936            while let Some(capture) = highlights.next_capture.as_ref() {
4937                if self.range.start < capture.node.start_byte() {
4938                    next_capture_start = capture.node.start_byte();
4939                    break;
4940                } else {
4941                    let highlight_id =
4942                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
4943                    highlights
4944                        .stack
4945                        .push((capture.node.end_byte(), highlight_id));
4946                    highlights.next_capture = highlights.captures.next();
4947                }
4948            }
4949        }
4950
4951        let mut diagnostic_endpoints = std::mem::take(&mut self.diagnostic_endpoints);
4952        if let Some(diagnostic_endpoints) = diagnostic_endpoints.as_mut() {
4953            while let Some(endpoint) = diagnostic_endpoints.peek().copied() {
4954                if endpoint.offset <= self.range.start {
4955                    self.update_diagnostic_depths(endpoint);
4956                    diagnostic_endpoints.next();
4957                    self.underline = endpoint.underline;
4958                } else {
4959                    next_diagnostic_endpoint = endpoint.offset;
4960                    break;
4961                }
4962            }
4963        }
4964        self.diagnostic_endpoints = diagnostic_endpoints;
4965
4966        if let Some(ChunkBitmaps {
4967            text: chunk,
4968            chars: chars_map,
4969            tabs,
4970        }) = self.chunks.peek_tabs()
4971        {
4972            let chunk_start = self.range.start;
4973            let mut chunk_end = (self.chunks.offset() + chunk.len())
4974                .min(next_capture_start)
4975                .min(next_diagnostic_endpoint);
4976            let mut highlight_id = None;
4977            if let Some(highlights) = self.highlights.as_ref()
4978                && let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last()
4979            {
4980                chunk_end = chunk_end.min(*parent_capture_end);
4981                highlight_id = Some(*parent_highlight_id);
4982            }
4983
4984            let slice =
4985                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
4986            let bit_end = chunk_end - self.chunks.offset();
4987
4988            let mask = if bit_end >= 128 {
4989                u128::MAX
4990            } else {
4991                (1u128 << bit_end) - 1
4992            };
4993            let tabs = (tabs >> (chunk_start - self.chunks.offset())) & mask;
4994            let chars_map = (chars_map >> (chunk_start - self.chunks.offset())) & mask;
4995
4996            self.range.start = chunk_end;
4997            if self.range.start == self.chunks.offset() + chunk.len() {
4998                self.chunks.next().unwrap();
4999            }
5000
5001            Some(Chunk {
5002                text: slice,
5003                syntax_highlight_id: highlight_id,
5004                underline: self.underline,
5005                diagnostic_severity: self.current_diagnostic_severity(),
5006                is_unnecessary: self.current_code_is_unnecessary(),
5007                tabs,
5008                chars: chars_map,
5009                ..Chunk::default()
5010            })
5011        } else {
5012            None
5013        }
5014    }
5015}
5016
5017impl operation_queue::Operation for Operation {
5018    fn lamport_timestamp(&self) -> clock::Lamport {
5019        match self {
5020            Operation::Buffer(_) => {
5021                unreachable!("buffer operations should never be deferred at this layer")
5022            }
5023            Operation::UpdateDiagnostics {
5024                lamport_timestamp, ..
5025            }
5026            | Operation::UpdateSelections {
5027                lamport_timestamp, ..
5028            }
5029            | Operation::UpdateCompletionTriggers {
5030                lamport_timestamp, ..
5031            }
5032            | Operation::UpdateLineEnding {
5033                lamport_timestamp, ..
5034            } => *lamport_timestamp,
5035        }
5036    }
5037}
5038
5039impl Default for Diagnostic {
5040    fn default() -> Self {
5041        Self {
5042            source: Default::default(),
5043            source_kind: DiagnosticSourceKind::Other,
5044            code: None,
5045            code_description: None,
5046            severity: DiagnosticSeverity::ERROR,
5047            message: Default::default(),
5048            markdown: None,
5049            group_id: 0,
5050            is_primary: false,
5051            is_disk_based: false,
5052            is_unnecessary: false,
5053            underline: true,
5054            data: None,
5055        }
5056    }
5057}
5058
5059impl IndentSize {
5060    /// Returns an [`IndentSize`] representing the given spaces.
5061    pub fn spaces(len: u32) -> Self {
5062        Self {
5063            len,
5064            kind: IndentKind::Space,
5065        }
5066    }
5067
5068    /// Returns an [`IndentSize`] representing a tab.
5069    pub fn tab() -> Self {
5070        Self {
5071            len: 1,
5072            kind: IndentKind::Tab,
5073        }
5074    }
5075
5076    /// An iterator over the characters represented by this [`IndentSize`].
5077    pub fn chars(&self) -> impl Iterator<Item = char> {
5078        iter::repeat(self.char()).take(self.len as usize)
5079    }
5080
5081    /// The character representation of this [`IndentSize`].
5082    pub fn char(&self) -> char {
5083        match self.kind {
5084            IndentKind::Space => ' ',
5085            IndentKind::Tab => '\t',
5086        }
5087    }
5088
5089    /// Consumes the current [`IndentSize`] and returns a new one that has
5090    /// been shrunk or enlarged by the given size along the given direction.
5091    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
5092        match direction {
5093            Ordering::Less => {
5094                if self.kind == size.kind && self.len >= size.len {
5095                    self.len -= size.len;
5096                }
5097            }
5098            Ordering::Equal => {}
5099            Ordering::Greater => {
5100                if self.len == 0 {
5101                    self = size;
5102                } else if self.kind == size.kind {
5103                    self.len += size.len;
5104                }
5105            }
5106        }
5107        self
5108    }
5109
5110    pub fn len_with_expanded_tabs(&self, tab_size: NonZeroU32) -> usize {
5111        match self.kind {
5112            IndentKind::Space => self.len as usize,
5113            IndentKind::Tab => self.len as usize * tab_size.get() as usize,
5114        }
5115    }
5116}
5117
5118#[cfg(any(test, feature = "test-support"))]
5119pub struct TestFile {
5120    pub path: Arc<Path>,
5121    pub root_name: String,
5122    pub local_root: Option<PathBuf>,
5123}
5124
5125#[cfg(any(test, feature = "test-support"))]
5126impl File for TestFile {
5127    fn path(&self) -> &Arc<Path> {
5128        &self.path
5129    }
5130
5131    fn full_path(&self, _: &gpui::App) -> PathBuf {
5132        PathBuf::from(&self.root_name).join(self.path.as_ref())
5133    }
5134
5135    fn as_local(&self) -> Option<&dyn LocalFile> {
5136        if self.local_root.is_some() {
5137            Some(self)
5138        } else {
5139            None
5140        }
5141    }
5142
5143    fn disk_state(&self) -> DiskState {
5144        unimplemented!()
5145    }
5146
5147    fn file_name<'a>(&'a self, _: &'a gpui::App) -> &'a std::ffi::OsStr {
5148        self.path().file_name().unwrap_or(self.root_name.as_ref())
5149    }
5150
5151    fn worktree_id(&self, _: &App) -> WorktreeId {
5152        WorktreeId::from_usize(0)
5153    }
5154
5155    fn to_proto(&self, _: &App) -> rpc::proto::File {
5156        unimplemented!()
5157    }
5158
5159    fn is_private(&self) -> bool {
5160        false
5161    }
5162}
5163
5164#[cfg(any(test, feature = "test-support"))]
5165impl LocalFile for TestFile {
5166    fn abs_path(&self, _cx: &App) -> PathBuf {
5167        PathBuf::from(self.local_root.as_ref().unwrap())
5168            .join(&self.root_name)
5169            .join(self.path.as_ref())
5170    }
5171
5172    fn load(&self, _cx: &App) -> Task<Result<String>> {
5173        unimplemented!()
5174    }
5175
5176    fn load_bytes(&self, _cx: &App) -> Task<Result<Vec<u8>>> {
5177        unimplemented!()
5178    }
5179}
5180
5181pub(crate) fn contiguous_ranges(
5182    values: impl Iterator<Item = u32>,
5183    max_len: usize,
5184) -> impl Iterator<Item = Range<u32>> {
5185    let mut values = values;
5186    let mut current_range: Option<Range<u32>> = None;
5187    std::iter::from_fn(move || {
5188        loop {
5189            if let Some(value) = values.next() {
5190                if let Some(range) = &mut current_range
5191                    && value == range.end
5192                    && range.len() < max_len
5193                {
5194                    range.end += 1;
5195                    continue;
5196                }
5197
5198                let prev_range = current_range.clone();
5199                current_range = Some(value..(value + 1));
5200                if prev_range.is_some() {
5201                    return prev_range;
5202                }
5203            } else {
5204                return current_range.take();
5205            }
5206        }
5207    })
5208}
5209
5210#[derive(Default, Debug)]
5211pub struct CharClassifier {
5212    scope: Option<LanguageScope>,
5213    scope_context: Option<CharScopeContext>,
5214    ignore_punctuation: bool,
5215}
5216
5217impl CharClassifier {
5218    pub fn new(scope: Option<LanguageScope>) -> Self {
5219        Self {
5220            scope,
5221            scope_context: None,
5222            ignore_punctuation: false,
5223        }
5224    }
5225
5226    pub fn scope_context(self, scope_context: Option<CharScopeContext>) -> Self {
5227        Self {
5228            scope_context,
5229            ..self
5230        }
5231    }
5232
5233    pub fn ignore_punctuation(self, ignore_punctuation: bool) -> Self {
5234        Self {
5235            ignore_punctuation,
5236            ..self
5237        }
5238    }
5239
5240    pub fn is_whitespace(&self, c: char) -> bool {
5241        self.kind(c) == CharKind::Whitespace
5242    }
5243
5244    pub fn is_word(&self, c: char) -> bool {
5245        self.kind(c) == CharKind::Word
5246    }
5247
5248    pub fn is_punctuation(&self, c: char) -> bool {
5249        self.kind(c) == CharKind::Punctuation
5250    }
5251
5252    pub fn kind_with(&self, c: char, ignore_punctuation: bool) -> CharKind {
5253        if c.is_alphanumeric() || c == '_' {
5254            return CharKind::Word;
5255        }
5256
5257        if let Some(scope) = &self.scope {
5258            let characters = match self.scope_context {
5259                Some(CharScopeContext::Completion) => scope.completion_query_characters(),
5260                Some(CharScopeContext::LinkedEdit) => scope.linked_edit_characters(),
5261                None => scope.word_characters(),
5262            };
5263            if let Some(characters) = characters
5264                && characters.contains(&c)
5265            {
5266                return CharKind::Word;
5267            }
5268        }
5269
5270        if c.is_whitespace() {
5271            return CharKind::Whitespace;
5272        }
5273
5274        if ignore_punctuation {
5275            CharKind::Word
5276        } else {
5277            CharKind::Punctuation
5278        }
5279    }
5280
5281    pub fn kind(&self, c: char) -> CharKind {
5282        self.kind_with(c, self.ignore_punctuation)
5283    }
5284}
5285
5286/// Find all of the ranges of whitespace that occur at the ends of lines
5287/// in the given rope.
5288///
5289/// This could also be done with a regex search, but this implementation
5290/// avoids copying text.
5291pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
5292    let mut ranges = Vec::new();
5293
5294    let mut offset = 0;
5295    let mut prev_chunk_trailing_whitespace_range = 0..0;
5296    for chunk in rope.chunks() {
5297        let mut prev_line_trailing_whitespace_range = 0..0;
5298        for (i, line) in chunk.split('\n').enumerate() {
5299            let line_end_offset = offset + line.len();
5300            let trimmed_line_len = line.trim_end_matches([' ', '\t']).len();
5301            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
5302
5303            if i == 0 && trimmed_line_len == 0 {
5304                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
5305            }
5306            if !prev_line_trailing_whitespace_range.is_empty() {
5307                ranges.push(prev_line_trailing_whitespace_range);
5308            }
5309
5310            offset = line_end_offset + 1;
5311            prev_line_trailing_whitespace_range = trailing_whitespace_range;
5312        }
5313
5314        offset -= 1;
5315        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
5316    }
5317
5318    if !prev_chunk_trailing_whitespace_range.is_empty() {
5319        ranges.push(prev_chunk_trailing_whitespace_range);
5320    }
5321
5322    ranges
5323}