buffer.rs

   1use crate::{
   2    DebugVariableCapture, 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, anyhow};
  21use async_watch as watch;
  22use clock::Lamport;
  23pub use clock::ReplicaId;
  24use collections::HashMap;
  25use fs::MTime;
  26use futures::channel::oneshot;
  27use gpui::{
  28    App, AppContext as _, Context, Entity, EventEmitter, HighlightStyle, SharedString, StyledText,
  29    Task, TaskLabel, TextStyle,
  30};
  31use lsp::{LanguageServerId, NumberOrString};
  32use parking_lot::Mutex;
  33use schemars::JsonSchema;
  34use serde::{Deserialize, Serialize};
  35use serde_json::Value;
  36use settings::WorktreeId;
  37use smallvec::SmallVec;
  38use smol::future::yield_now;
  39use std::{
  40    any::Any,
  41    borrow::Cow,
  42    cell::Cell,
  43    cmp::{self, Ordering, Reverse},
  44    collections::{BTreeMap, BTreeSet},
  45    ffi::OsStr,
  46    future::Future,
  47    iter::{self, Iterator, Peekable},
  48    mem,
  49    num::NonZeroU32,
  50    ops::{Deref, Range},
  51    path::{Path, PathBuf},
  52    rc,
  53    sync::{Arc, LazyLock},
  54    time::{Duration, Instant},
  55    vec,
  56};
  57use sum_tree::TreeMap;
  58use text::operation_queue::OperationQueue;
  59use text::*;
  60pub use text::{
  61    Anchor, Bias, Buffer as TextBuffer, BufferId, BufferSnapshot as TextBufferSnapshot, Edit,
  62    OffsetRangeExt, OffsetUtf16, Patch, Point, PointUtf16, Rope, Selection, SelectionGoal,
  63    Subscription, TextDimension, TextSummary, ToOffset, ToOffsetUtf16, ToPoint, ToPointUtf16,
  64    Transaction, TransactionId, Unclipped,
  65};
  66use theme::{ActiveTheme as _, SyntaxTheme};
  67#[cfg(any(test, feature = "test-support"))]
  68use util::RandomCharIter;
  69use util::{RangeExt, debug_panic, maybe};
  70
  71#[cfg(any(test, feature = "test-support"))]
  72pub use {tree_sitter_rust, tree_sitter_typescript};
  73
  74pub use lsp::DiagnosticSeverity;
  75
  76#[derive(Debug)]
  77pub struct DebugVariableRanges {
  78    pub buffer_id: BufferId,
  79    pub range: Range<usize>,
  80}
  81
  82/// A label for the background task spawned by the buffer to compute
  83/// a diff against the contents of its file.
  84pub static BUFFER_DIFF_TASK: LazyLock<TaskLabel> = LazyLock::new(TaskLabel::new);
  85
  86/// Indicate whether a [`Buffer`] has permissions to edit.
  87#[derive(PartialEq, Clone, Copy, Debug)]
  88pub enum Capability {
  89    /// The buffer is a mutable replica.
  90    ReadWrite,
  91    /// The buffer is a read-only replica.
  92    ReadOnly,
  93}
  94
  95pub type BufferRow = u32;
  96
  97/// An in-memory representation of a source code file, including its text,
  98/// syntax trees, git status, and diagnostics.
  99pub struct Buffer {
 100    text: TextBuffer,
 101    branch_state: Option<BufferBranchState>,
 102    /// Filesystem state, `None` when there is no path.
 103    file: Option<Arc<dyn File>>,
 104    /// The mtime of the file when this buffer was last loaded from
 105    /// or saved to disk.
 106    saved_mtime: Option<MTime>,
 107    /// The version vector when this buffer was last loaded from
 108    /// or saved to disk.
 109    saved_version: clock::Global,
 110    preview_version: clock::Global,
 111    transaction_depth: usize,
 112    was_dirty_before_starting_transaction: Option<bool>,
 113    reload_task: Option<Task<Result<()>>>,
 114    language: Option<Arc<Language>>,
 115    autoindent_requests: Vec<Arc<AutoindentRequest>>,
 116    pending_autoindent: Option<Task<()>>,
 117    sync_parse_timeout: Duration,
 118    syntax_map: Mutex<SyntaxMap>,
 119    reparse: Option<Task<()>>,
 120    parse_status: (watch::Sender<ParseStatus>, watch::Receiver<ParseStatus>),
 121    non_text_state_update_count: usize,
 122    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 123    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 124    diagnostics_timestamp: clock::Lamport,
 125    completion_triggers: BTreeSet<String>,
 126    completion_triggers_per_language_server: HashMap<LanguageServerId, BTreeSet<String>>,
 127    completion_triggers_timestamp: clock::Lamport,
 128    deferred_ops: OperationQueue<Operation>,
 129    capability: Capability,
 130    has_conflict: bool,
 131    /// Memoize calls to has_changes_since(saved_version).
 132    /// The contents of a cell are (self.version, has_changes) at the time of a last call.
 133    has_unsaved_edits: Cell<(clock::Global, bool)>,
 134    change_bits: Vec<rc::Weak<Cell<bool>>>,
 135    _subscriptions: Vec<gpui::Subscription>,
 136}
 137
 138#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 139pub enum ParseStatus {
 140    Idle,
 141    Parsing,
 142}
 143
 144struct BufferBranchState {
 145    base_buffer: Entity<Buffer>,
 146    merged_operations: Vec<Lamport>,
 147}
 148
 149/// An immutable, cheaply cloneable representation of a fixed
 150/// state of a buffer.
 151pub struct BufferSnapshot {
 152    pub text: text::BufferSnapshot,
 153    pub(crate) syntax: SyntaxSnapshot,
 154    file: Option<Arc<dyn File>>,
 155    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 156    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 157    language: Option<Arc<Language>>,
 158    non_text_state_update_count: usize,
 159}
 160
 161/// The kind and amount of indentation in a particular line. For now,
 162/// assumes that indentation is all the same character.
 163#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 164pub struct IndentSize {
 165    /// The number of bytes that comprise the indentation.
 166    pub len: u32,
 167    /// The kind of whitespace used for indentation.
 168    pub kind: IndentKind,
 169}
 170
 171/// A whitespace character that's used for indentation.
 172#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 173pub enum IndentKind {
 174    /// An ASCII space character.
 175    #[default]
 176    Space,
 177    /// An ASCII tab character.
 178    Tab,
 179}
 180
 181/// The shape of a selection cursor.
 182#[derive(Copy, Clone, Debug, Default, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 183#[serde(rename_all = "snake_case")]
 184pub enum CursorShape {
 185    /// A vertical bar
 186    #[default]
 187    Bar,
 188    /// A block that surrounds the following character
 189    Block,
 190    /// An underline that runs along the following character
 191    Underline,
 192    /// A box drawn around the following character
 193    Hollow,
 194}
 195
 196#[derive(Clone, Debug)]
 197struct SelectionSet {
 198    line_mode: bool,
 199    cursor_shape: CursorShape,
 200    selections: Arc<[Selection<Anchor>]>,
 201    lamport_timestamp: clock::Lamport,
 202}
 203
 204/// A diagnostic associated with a certain range of a buffer.
 205#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 206pub struct Diagnostic {
 207    /// The name of the service that produced this diagnostic.
 208    pub source: Option<String>,
 209    /// A machine-readable code that identifies this diagnostic.
 210    pub code: Option<NumberOrString>,
 211    pub code_description: Option<lsp::Url>,
 212    /// Whether this diagnostic is a hint, warning, or error.
 213    pub severity: DiagnosticSeverity,
 214    /// The human-readable message associated with this diagnostic.
 215    pub message: String,
 216    /// The human-readable message (in markdown format)
 217    pub markdown: Option<String>,
 218    /// An id that identifies the group to which this diagnostic belongs.
 219    ///
 220    /// When a language server produces a diagnostic with
 221    /// one or more associated diagnostics, those diagnostics are all
 222    /// assigned a single group ID.
 223    pub group_id: usize,
 224    /// Whether this diagnostic is the primary diagnostic for its group.
 225    ///
 226    /// In a given group, the primary diagnostic is the top-level diagnostic
 227    /// returned by the language server. The non-primary diagnostics are the
 228    /// associated diagnostics.
 229    pub is_primary: bool,
 230    /// Whether this diagnostic is considered to originate from an analysis of
 231    /// files on disk, as opposed to any unsaved buffer contents. This is a
 232    /// property of a given diagnostic source, and is configured for a given
 233    /// language server via the [`LspAdapter::disk_based_diagnostic_sources`](crate::LspAdapter::disk_based_diagnostic_sources) method
 234    /// for the language server.
 235    pub is_disk_based: bool,
 236    /// Whether this diagnostic marks unnecessary code.
 237    pub is_unnecessary: bool,
 238    /// Data from language server that produced this diagnostic. Passed back to the LS when we request code actions for this diagnostic.
 239    pub data: Option<Value>,
 240}
 241
 242/// An operation used to synchronize this buffer with its other replicas.
 243#[derive(Clone, Debug, PartialEq)]
 244pub enum Operation {
 245    /// A text operation.
 246    Buffer(text::Operation),
 247
 248    /// An update to the buffer's diagnostics.
 249    UpdateDiagnostics {
 250        /// The id of the language server that produced the new diagnostics.
 251        server_id: LanguageServerId,
 252        /// The diagnostics.
 253        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 254        /// The buffer's lamport timestamp.
 255        lamport_timestamp: clock::Lamport,
 256    },
 257
 258    /// An update to the most recent selections in this buffer.
 259    UpdateSelections {
 260        /// The selections.
 261        selections: Arc<[Selection<Anchor>]>,
 262        /// The buffer's lamport timestamp.
 263        lamport_timestamp: clock::Lamport,
 264        /// Whether the selections are in 'line mode'.
 265        line_mode: bool,
 266        /// The [`CursorShape`] associated with these selections.
 267        cursor_shape: CursorShape,
 268    },
 269
 270    /// An update to the characters that should trigger autocompletion
 271    /// for this buffer.
 272    UpdateCompletionTriggers {
 273        /// The characters that trigger autocompletion.
 274        triggers: Vec<String>,
 275        /// The buffer's lamport timestamp.
 276        lamport_timestamp: clock::Lamport,
 277        /// The language server ID.
 278        server_id: LanguageServerId,
 279    },
 280}
 281
 282/// An event that occurs in a buffer.
 283#[derive(Clone, Debug, PartialEq)]
 284pub enum BufferEvent {
 285    /// The buffer was changed in a way that must be
 286    /// propagated to its other replicas.
 287    Operation {
 288        operation: Operation,
 289        is_local: bool,
 290    },
 291    /// The buffer was edited.
 292    Edited,
 293    /// The buffer's `dirty` bit changed.
 294    DirtyChanged,
 295    /// The buffer was saved.
 296    Saved,
 297    /// The buffer's file was changed on disk.
 298    FileHandleChanged,
 299    /// The buffer was reloaded.
 300    Reloaded,
 301    /// The buffer is in need of a reload
 302    ReloadNeeded,
 303    /// The buffer's language was changed.
 304    LanguageChanged,
 305    /// The buffer's syntax trees were updated.
 306    Reparsed,
 307    /// The buffer's diagnostics were updated.
 308    DiagnosticsUpdated,
 309    /// The buffer gained or lost editing capabilities.
 310    CapabilityChanged,
 311    /// The buffer was explicitly requested to close.
 312    Closed,
 313    /// The buffer was discarded when closing.
 314    Discarded,
 315}
 316
 317/// The file associated with a buffer.
 318pub trait File: Send + Sync + Any {
 319    /// Returns the [`LocalFile`] associated with this file, if the
 320    /// file is local.
 321    fn as_local(&self) -> Option<&dyn LocalFile>;
 322
 323    /// Returns whether this file is local.
 324    fn is_local(&self) -> bool {
 325        self.as_local().is_some()
 326    }
 327
 328    /// Returns whether the file is new, exists in storage, or has been deleted. Includes metadata
 329    /// only available in some states, such as modification time.
 330    fn disk_state(&self) -> DiskState;
 331
 332    /// Returns the path of this file relative to the worktree's root directory.
 333    fn path(&self) -> &Arc<Path>;
 334
 335    /// Returns the path of this file relative to the worktree's parent directory (this means it
 336    /// includes the name of the worktree's root folder).
 337    fn full_path(&self, cx: &App) -> PathBuf;
 338
 339    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 340    /// of its worktree, then this method will return the name of the worktree itself.
 341    fn file_name<'a>(&'a self, cx: &'a App) -> &'a OsStr;
 342
 343    /// Returns the id of the worktree to which this file belongs.
 344    ///
 345    /// This is needed for looking up project-specific settings.
 346    fn worktree_id(&self, cx: &App) -> WorktreeId;
 347
 348    /// Converts this file into a protobuf message.
 349    fn to_proto(&self, cx: &App) -> rpc::proto::File;
 350
 351    /// Return whether Zed considers this to be a private file.
 352    fn is_private(&self) -> bool;
 353}
 354
 355/// The file's storage status - whether it's stored (`Present`), and if so when it was last
 356/// modified. In the case where the file is not stored, it can be either `New` or `Deleted`. In the
 357/// UI these two states are distinguished. For example, the buffer tab does not display a deletion
 358/// indicator for new files.
 359#[derive(Copy, Clone, Debug, PartialEq)]
 360pub enum DiskState {
 361    /// File created in Zed that has not been saved.
 362    New,
 363    /// File present on the filesystem.
 364    Present { mtime: MTime },
 365    /// Deleted file that was previously present.
 366    Deleted,
 367}
 368
 369impl DiskState {
 370    /// Returns the file's last known modification time on disk.
 371    pub fn mtime(self) -> Option<MTime> {
 372        match self {
 373            DiskState::New => None,
 374            DiskState::Present { mtime } => Some(mtime),
 375            DiskState::Deleted => None,
 376        }
 377    }
 378
 379    pub fn exists(&self) -> bool {
 380        match self {
 381            DiskState::New => false,
 382            DiskState::Present { .. } => true,
 383            DiskState::Deleted => false,
 384        }
 385    }
 386}
 387
 388/// The file associated with a buffer, in the case where the file is on the local disk.
 389pub trait LocalFile: File {
 390    /// Returns the absolute path of this file
 391    fn abs_path(&self, cx: &App) -> PathBuf;
 392
 393    /// Loads the file contents from disk and returns them as a UTF-8 encoded string.
 394    fn load(&self, cx: &App) -> Task<Result<String>>;
 395
 396    /// Loads the file's contents from disk.
 397    fn load_bytes(&self, cx: &App) -> Task<Result<Vec<u8>>>;
 398}
 399
 400/// The auto-indent behavior associated with an editing operation.
 401/// For some editing operations, each affected line of text has its
 402/// indentation recomputed. For other operations, the entire block
 403/// of edited text is adjusted uniformly.
 404#[derive(Clone, Debug)]
 405pub enum AutoindentMode {
 406    /// Indent each line of inserted text.
 407    EachLine,
 408    /// Apply the same indentation adjustment to all of the lines
 409    /// in a given insertion.
 410    Block {
 411        /// The original indentation column of the first line of each
 412        /// insertion, if it has been copied.
 413        ///
 414        /// Knowing this makes it possible to preserve the relative indentation
 415        /// of every line in the insertion from when it was copied.
 416        ///
 417        /// If the original indent column is `a`, and the first line of insertion
 418        /// is then auto-indented to column `b`, then every other line of
 419        /// the insertion will be auto-indented to column `b - a`
 420        original_indent_columns: Vec<Option<u32>>,
 421    },
 422}
 423
 424#[derive(Clone)]
 425struct AutoindentRequest {
 426    before_edit: BufferSnapshot,
 427    entries: Vec<AutoindentRequestEntry>,
 428    is_block_mode: bool,
 429    ignore_empty_lines: bool,
 430}
 431
 432#[derive(Debug, Clone)]
 433struct AutoindentRequestEntry {
 434    /// A range of the buffer whose indentation should be adjusted.
 435    range: Range<Anchor>,
 436    /// Whether or not these lines should be considered brand new, for the
 437    /// purpose of auto-indent. When text is not new, its indentation will
 438    /// only be adjusted if the suggested indentation level has *changed*
 439    /// since the edit was made.
 440    first_line_is_new: bool,
 441    indent_size: IndentSize,
 442    original_indent_column: Option<u32>,
 443}
 444
 445#[derive(Debug)]
 446struct IndentSuggestion {
 447    basis_row: u32,
 448    delta: Ordering,
 449    within_error: bool,
 450}
 451
 452struct BufferChunkHighlights<'a> {
 453    captures: SyntaxMapCaptures<'a>,
 454    next_capture: Option<SyntaxMapCapture<'a>>,
 455    stack: Vec<(usize, HighlightId)>,
 456    highlight_maps: Vec<HighlightMap>,
 457}
 458
 459/// An iterator that yields chunks of a buffer's text, along with their
 460/// syntax highlights and diagnostic status.
 461pub struct BufferChunks<'a> {
 462    buffer_snapshot: Option<&'a BufferSnapshot>,
 463    range: Range<usize>,
 464    chunks: text::Chunks<'a>,
 465    diagnostic_endpoints: Option<Peekable<vec::IntoIter<DiagnosticEndpoint>>>,
 466    error_depth: usize,
 467    warning_depth: usize,
 468    information_depth: usize,
 469    hint_depth: usize,
 470    unnecessary_depth: usize,
 471    highlights: Option<BufferChunkHighlights<'a>>,
 472}
 473
 474/// A chunk of a buffer's text, along with its syntax highlight and
 475/// diagnostic status.
 476#[derive(Clone, Debug, Default)]
 477pub struct Chunk<'a> {
 478    /// The text of the chunk.
 479    pub text: &'a str,
 480    /// The syntax highlighting style of the chunk.
 481    pub syntax_highlight_id: Option<HighlightId>,
 482    /// The highlight style that has been applied to this chunk in
 483    /// the editor.
 484    pub highlight_style: Option<HighlightStyle>,
 485    /// The severity of diagnostic associated with this chunk, if any.
 486    pub diagnostic_severity: Option<DiagnosticSeverity>,
 487    /// Whether this chunk of text is marked as unnecessary.
 488    pub is_unnecessary: bool,
 489    /// Whether this chunk of text was originally a tab character.
 490    pub is_tab: bool,
 491}
 492
 493/// A set of edits to a given version of a buffer, computed asynchronously.
 494#[derive(Debug)]
 495pub struct Diff {
 496    pub base_version: clock::Global,
 497    pub line_ending: LineEnding,
 498    pub edits: Vec<(Range<usize>, Arc<str>)>,
 499}
 500
 501#[derive(Clone, Copy)]
 502pub(crate) struct DiagnosticEndpoint {
 503    offset: usize,
 504    is_start: bool,
 505    severity: DiagnosticSeverity,
 506    is_unnecessary: bool,
 507}
 508
 509/// A class of characters, used for characterizing a run of text.
 510#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 511pub enum CharKind {
 512    /// Whitespace.
 513    Whitespace,
 514    /// Punctuation.
 515    Punctuation,
 516    /// Word.
 517    Word,
 518}
 519
 520/// A runnable is a set of data about a region that could be resolved into a task
 521pub struct Runnable {
 522    pub tags: SmallVec<[RunnableTag; 1]>,
 523    pub language: Arc<Language>,
 524    pub buffer: BufferId,
 525}
 526
 527#[derive(Default, Clone, Debug)]
 528pub struct HighlightedText {
 529    pub text: SharedString,
 530    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 531}
 532
 533#[derive(Default, Debug)]
 534struct HighlightedTextBuilder {
 535    pub text: String,
 536    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 537}
 538
 539impl HighlightedText {
 540    pub fn from_buffer_range<T: ToOffset>(
 541        range: Range<T>,
 542        snapshot: &text::BufferSnapshot,
 543        syntax_snapshot: &SyntaxSnapshot,
 544        override_style: Option<HighlightStyle>,
 545        syntax_theme: &SyntaxTheme,
 546    ) -> Self {
 547        let mut highlighted_text = HighlightedTextBuilder::default();
 548        highlighted_text.add_text_from_buffer_range(
 549            range,
 550            snapshot,
 551            syntax_snapshot,
 552            override_style,
 553            syntax_theme,
 554        );
 555        highlighted_text.build()
 556    }
 557
 558    pub fn to_styled_text(&self, default_style: &TextStyle) -> StyledText {
 559        gpui::StyledText::new(self.text.clone())
 560            .with_default_highlights(default_style, self.highlights.iter().cloned())
 561    }
 562
 563    /// Returns the first line without leading whitespace unless highlighted
 564    /// and a boolean indicating if there are more lines after
 565    pub fn first_line_preview(self) -> (Self, bool) {
 566        let newline_ix = self.text.find('\n').unwrap_or(self.text.len());
 567        let first_line = &self.text[..newline_ix];
 568
 569        // Trim leading whitespace, unless an edit starts prior to it.
 570        let mut preview_start_ix = first_line.len() - first_line.trim_start().len();
 571        if let Some((first_highlight_range, _)) = self.highlights.first() {
 572            preview_start_ix = preview_start_ix.min(first_highlight_range.start);
 573        }
 574
 575        let preview_text = &first_line[preview_start_ix..];
 576        let preview_highlights = self
 577            .highlights
 578            .into_iter()
 579            .take_while(|(range, _)| range.start < newline_ix)
 580            .filter_map(|(mut range, highlight)| {
 581                range.start = range.start.saturating_sub(preview_start_ix);
 582                range.end = range.end.saturating_sub(preview_start_ix).min(newline_ix);
 583                if range.is_empty() {
 584                    None
 585                } else {
 586                    Some((range, highlight))
 587                }
 588            });
 589
 590        let preview = Self {
 591            text: SharedString::new(preview_text),
 592            highlights: preview_highlights.collect(),
 593        };
 594
 595        (preview, self.text.len() > newline_ix)
 596    }
 597}
 598
 599impl HighlightedTextBuilder {
 600    pub fn build(self) -> HighlightedText {
 601        HighlightedText {
 602            text: self.text.into(),
 603            highlights: self.highlights,
 604        }
 605    }
 606
 607    pub fn add_text_from_buffer_range<T: ToOffset>(
 608        &mut self,
 609        range: Range<T>,
 610        snapshot: &text::BufferSnapshot,
 611        syntax_snapshot: &SyntaxSnapshot,
 612        override_style: Option<HighlightStyle>,
 613        syntax_theme: &SyntaxTheme,
 614    ) {
 615        let range = range.to_offset(snapshot);
 616        for chunk in Self::highlighted_chunks(range, snapshot, syntax_snapshot) {
 617            let start = self.text.len();
 618            self.text.push_str(chunk.text);
 619            let end = self.text.len();
 620
 621            if let Some(mut highlight_style) = chunk
 622                .syntax_highlight_id
 623                .and_then(|id| id.style(syntax_theme))
 624            {
 625                if let Some(override_style) = override_style {
 626                    highlight_style.highlight(override_style);
 627                }
 628                self.highlights.push((start..end, highlight_style));
 629            } else if let Some(override_style) = override_style {
 630                self.highlights.push((start..end, override_style));
 631            }
 632        }
 633    }
 634
 635    fn highlighted_chunks<'a>(
 636        range: Range<usize>,
 637        snapshot: &'a text::BufferSnapshot,
 638        syntax_snapshot: &'a SyntaxSnapshot,
 639    ) -> BufferChunks<'a> {
 640        let captures = syntax_snapshot.captures(range.clone(), snapshot, |grammar| {
 641            grammar.highlights_query.as_ref()
 642        });
 643
 644        let highlight_maps = captures
 645            .grammars()
 646            .iter()
 647            .map(|grammar| grammar.highlight_map())
 648            .collect();
 649
 650        BufferChunks::new(
 651            snapshot.as_rope(),
 652            range,
 653            Some((captures, highlight_maps)),
 654            false,
 655            None,
 656        )
 657    }
 658}
 659
 660#[derive(Clone)]
 661pub struct EditPreview {
 662    old_snapshot: text::BufferSnapshot,
 663    applied_edits_snapshot: text::BufferSnapshot,
 664    syntax_snapshot: SyntaxSnapshot,
 665}
 666
 667impl EditPreview {
 668    pub fn highlight_edits(
 669        &self,
 670        current_snapshot: &BufferSnapshot,
 671        edits: &[(Range<Anchor>, String)],
 672        include_deletions: bool,
 673        cx: &App,
 674    ) -> HighlightedText {
 675        let Some(visible_range_in_preview_snapshot) = self.compute_visible_range(edits) else {
 676            return HighlightedText::default();
 677        };
 678
 679        let mut highlighted_text = HighlightedTextBuilder::default();
 680
 681        let mut offset_in_preview_snapshot = visible_range_in_preview_snapshot.start;
 682
 683        let insertion_highlight_style = HighlightStyle {
 684            background_color: Some(cx.theme().status().created_background),
 685            ..Default::default()
 686        };
 687        let deletion_highlight_style = HighlightStyle {
 688            background_color: Some(cx.theme().status().deleted_background),
 689            ..Default::default()
 690        };
 691        let syntax_theme = cx.theme().syntax();
 692
 693        for (range, edit_text) in edits {
 694            let edit_new_end_in_preview_snapshot = range
 695                .end
 696                .bias_right(&self.old_snapshot)
 697                .to_offset(&self.applied_edits_snapshot);
 698            let edit_start_in_preview_snapshot = edit_new_end_in_preview_snapshot - edit_text.len();
 699
 700            let unchanged_range_in_preview_snapshot =
 701                offset_in_preview_snapshot..edit_start_in_preview_snapshot;
 702            if !unchanged_range_in_preview_snapshot.is_empty() {
 703                highlighted_text.add_text_from_buffer_range(
 704                    unchanged_range_in_preview_snapshot,
 705                    &self.applied_edits_snapshot,
 706                    &self.syntax_snapshot,
 707                    None,
 708                    &syntax_theme,
 709                );
 710            }
 711
 712            let range_in_current_snapshot = range.to_offset(current_snapshot);
 713            if include_deletions && !range_in_current_snapshot.is_empty() {
 714                highlighted_text.add_text_from_buffer_range(
 715                    range_in_current_snapshot,
 716                    &current_snapshot.text,
 717                    &current_snapshot.syntax,
 718                    Some(deletion_highlight_style),
 719                    &syntax_theme,
 720                );
 721            }
 722
 723            if !edit_text.is_empty() {
 724                highlighted_text.add_text_from_buffer_range(
 725                    edit_start_in_preview_snapshot..edit_new_end_in_preview_snapshot,
 726                    &self.applied_edits_snapshot,
 727                    &self.syntax_snapshot,
 728                    Some(insertion_highlight_style),
 729                    &syntax_theme,
 730                );
 731            }
 732
 733            offset_in_preview_snapshot = edit_new_end_in_preview_snapshot;
 734        }
 735
 736        highlighted_text.add_text_from_buffer_range(
 737            offset_in_preview_snapshot..visible_range_in_preview_snapshot.end,
 738            &self.applied_edits_snapshot,
 739            &self.syntax_snapshot,
 740            None,
 741            &syntax_theme,
 742        );
 743
 744        highlighted_text.build()
 745    }
 746
 747    fn compute_visible_range(&self, edits: &[(Range<Anchor>, String)]) -> Option<Range<usize>> {
 748        let (first, _) = edits.first()?;
 749        let (last, _) = edits.last()?;
 750
 751        let start = first
 752            .start
 753            .bias_left(&self.old_snapshot)
 754            .to_point(&self.applied_edits_snapshot);
 755        let end = last
 756            .end
 757            .bias_right(&self.old_snapshot)
 758            .to_point(&self.applied_edits_snapshot);
 759
 760        // Ensure that the first line of the first edit and the last line of the last edit are always fully visible
 761        let range = Point::new(start.row, 0)
 762            ..Point::new(end.row, self.applied_edits_snapshot.line_len(end.row));
 763
 764        Some(range.to_offset(&self.applied_edits_snapshot))
 765    }
 766}
 767
 768#[derive(Clone, Debug, PartialEq, Eq)]
 769pub struct BracketMatch {
 770    pub open_range: Range<usize>,
 771    pub close_range: Range<usize>,
 772    pub newline_only: bool,
 773}
 774
 775impl Buffer {
 776    /// Create a new buffer with the given base text.
 777    pub fn local<T: Into<String>>(base_text: T, cx: &Context<Self>) -> Self {
 778        Self::build(
 779            TextBuffer::new(0, cx.entity_id().as_non_zero_u64().into(), base_text.into()),
 780            None,
 781            Capability::ReadWrite,
 782        )
 783    }
 784
 785    /// Create a new buffer with the given base text that has proper line endings and other normalization applied.
 786    pub fn local_normalized(
 787        base_text_normalized: Rope,
 788        line_ending: LineEnding,
 789        cx: &Context<Self>,
 790    ) -> Self {
 791        Self::build(
 792            TextBuffer::new_normalized(
 793                0,
 794                cx.entity_id().as_non_zero_u64().into(),
 795                line_ending,
 796                base_text_normalized,
 797            ),
 798            None,
 799            Capability::ReadWrite,
 800        )
 801    }
 802
 803    /// Create a new buffer that is a replica of a remote buffer.
 804    pub fn remote(
 805        remote_id: BufferId,
 806        replica_id: ReplicaId,
 807        capability: Capability,
 808        base_text: impl Into<String>,
 809    ) -> Self {
 810        Self::build(
 811            TextBuffer::new(replica_id, remote_id, base_text.into()),
 812            None,
 813            capability,
 814        )
 815    }
 816
 817    /// Create a new buffer that is a replica of a remote buffer, populating its
 818    /// state from the given protobuf message.
 819    pub fn from_proto(
 820        replica_id: ReplicaId,
 821        capability: Capability,
 822        message: proto::BufferState,
 823        file: Option<Arc<dyn File>>,
 824    ) -> Result<Self> {
 825        let buffer_id = BufferId::new(message.id)
 826            .with_context(|| anyhow!("Could not deserialize buffer_id"))?;
 827        let buffer = TextBuffer::new(replica_id, buffer_id, message.base_text);
 828        let mut this = Self::build(buffer, file, capability);
 829        this.text.set_line_ending(proto::deserialize_line_ending(
 830            rpc::proto::LineEnding::from_i32(message.line_ending)
 831                .ok_or_else(|| anyhow!("missing line_ending"))?,
 832        ));
 833        this.saved_version = proto::deserialize_version(&message.saved_version);
 834        this.saved_mtime = message.saved_mtime.map(|time| time.into());
 835        Ok(this)
 836    }
 837
 838    /// Serialize the buffer's state to a protobuf message.
 839    pub fn to_proto(&self, cx: &App) -> proto::BufferState {
 840        proto::BufferState {
 841            id: self.remote_id().into(),
 842            file: self.file.as_ref().map(|f| f.to_proto(cx)),
 843            base_text: self.base_text().to_string(),
 844            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 845            saved_version: proto::serialize_version(&self.saved_version),
 846            saved_mtime: self.saved_mtime.map(|time| time.into()),
 847        }
 848    }
 849
 850    /// Serialize as protobufs all of the changes to the buffer since the given version.
 851    pub fn serialize_ops(
 852        &self,
 853        since: Option<clock::Global>,
 854        cx: &App,
 855    ) -> Task<Vec<proto::Operation>> {
 856        let mut operations = Vec::new();
 857        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 858
 859        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 860            proto::serialize_operation(&Operation::UpdateSelections {
 861                selections: set.selections.clone(),
 862                lamport_timestamp: set.lamport_timestamp,
 863                line_mode: set.line_mode,
 864                cursor_shape: set.cursor_shape,
 865            })
 866        }));
 867
 868        for (server_id, diagnostics) in &self.diagnostics {
 869            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 870                lamport_timestamp: self.diagnostics_timestamp,
 871                server_id: *server_id,
 872                diagnostics: diagnostics.iter().cloned().collect(),
 873            }));
 874        }
 875
 876        for (server_id, completions) in &self.completion_triggers_per_language_server {
 877            operations.push(proto::serialize_operation(
 878                &Operation::UpdateCompletionTriggers {
 879                    triggers: completions.iter().cloned().collect(),
 880                    lamport_timestamp: self.completion_triggers_timestamp,
 881                    server_id: *server_id,
 882                },
 883            ));
 884        }
 885
 886        let text_operations = self.text.operations().clone();
 887        cx.background_spawn(async move {
 888            let since = since.unwrap_or_default();
 889            operations.extend(
 890                text_operations
 891                    .iter()
 892                    .filter(|(_, op)| !since.observed(op.timestamp()))
 893                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 894            );
 895            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 896            operations
 897        })
 898    }
 899
 900    /// Assign a language to the buffer, returning the buffer.
 901    pub fn with_language(mut self, language: Arc<Language>, cx: &mut Context<Self>) -> Self {
 902        self.set_language(Some(language), cx);
 903        self
 904    }
 905
 906    /// Returns the [`Capability`] of this buffer.
 907    pub fn capability(&self) -> Capability {
 908        self.capability
 909    }
 910
 911    /// Whether this buffer can only be read.
 912    pub fn read_only(&self) -> bool {
 913        self.capability == Capability::ReadOnly
 914    }
 915
 916    /// Builds a [`Buffer`] with the given underlying [`TextBuffer`], diff base, [`File`] and [`Capability`].
 917    pub fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>, capability: Capability) -> Self {
 918        let saved_mtime = file.as_ref().and_then(|file| file.disk_state().mtime());
 919        let snapshot = buffer.snapshot();
 920        let syntax_map = Mutex::new(SyntaxMap::new(&snapshot));
 921        Self {
 922            saved_mtime,
 923            saved_version: buffer.version(),
 924            preview_version: buffer.version(),
 925            reload_task: None,
 926            transaction_depth: 0,
 927            was_dirty_before_starting_transaction: None,
 928            has_unsaved_edits: Cell::new((buffer.version(), false)),
 929            text: buffer,
 930            branch_state: None,
 931            file,
 932            capability,
 933            syntax_map,
 934            reparse: None,
 935            non_text_state_update_count: 0,
 936            sync_parse_timeout: Duration::from_millis(1),
 937            parse_status: async_watch::channel(ParseStatus::Idle),
 938            autoindent_requests: Default::default(),
 939            pending_autoindent: Default::default(),
 940            language: None,
 941            remote_selections: Default::default(),
 942            diagnostics: Default::default(),
 943            diagnostics_timestamp: Default::default(),
 944            completion_triggers: Default::default(),
 945            completion_triggers_per_language_server: Default::default(),
 946            completion_triggers_timestamp: Default::default(),
 947            deferred_ops: OperationQueue::new(),
 948            has_conflict: false,
 949            change_bits: Default::default(),
 950            _subscriptions: Vec::new(),
 951        }
 952    }
 953
 954    pub fn build_snapshot(
 955        text: Rope,
 956        language: Option<Arc<Language>>,
 957        language_registry: Option<Arc<LanguageRegistry>>,
 958        cx: &mut App,
 959    ) -> impl Future<Output = BufferSnapshot> + use<> {
 960        let entity_id = cx.reserve_entity::<Self>().entity_id();
 961        let buffer_id = entity_id.as_non_zero_u64().into();
 962        async move {
 963            let text =
 964                TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
 965            let mut syntax = SyntaxMap::new(&text).snapshot();
 966            if let Some(language) = language.clone() {
 967                let text = text.clone();
 968                let language = language.clone();
 969                let language_registry = language_registry.clone();
 970                syntax.reparse(&text, language_registry, language);
 971            }
 972            BufferSnapshot {
 973                text,
 974                syntax,
 975                file: None,
 976                diagnostics: Default::default(),
 977                remote_selections: Default::default(),
 978                language,
 979                non_text_state_update_count: 0,
 980            }
 981        }
 982    }
 983
 984    pub fn build_empty_snapshot(cx: &mut App) -> BufferSnapshot {
 985        let entity_id = cx.reserve_entity::<Self>().entity_id();
 986        let buffer_id = entity_id.as_non_zero_u64().into();
 987        let text =
 988            TextBuffer::new_normalized(0, buffer_id, Default::default(), Rope::new()).snapshot();
 989        let syntax = SyntaxMap::new(&text).snapshot();
 990        BufferSnapshot {
 991            text,
 992            syntax,
 993            file: None,
 994            diagnostics: Default::default(),
 995            remote_selections: Default::default(),
 996            language: None,
 997            non_text_state_update_count: 0,
 998        }
 999    }
1000
1001    #[cfg(any(test, feature = "test-support"))]
1002    pub fn build_snapshot_sync(
1003        text: Rope,
1004        language: Option<Arc<Language>>,
1005        language_registry: Option<Arc<LanguageRegistry>>,
1006        cx: &mut App,
1007    ) -> BufferSnapshot {
1008        let entity_id = cx.reserve_entity::<Self>().entity_id();
1009        let buffer_id = entity_id.as_non_zero_u64().into();
1010        let text = TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
1011        let mut syntax = SyntaxMap::new(&text).snapshot();
1012        if let Some(language) = language.clone() {
1013            let text = text.clone();
1014            let 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    /// Retrieve a snapshot of the buffer's current state. This is computationally
1030    /// cheap, and allows reading from the buffer on a background thread.
1031    pub fn snapshot(&self) -> BufferSnapshot {
1032        let text = self.text.snapshot();
1033        let mut syntax_map = self.syntax_map.lock();
1034        syntax_map.interpolate(&text);
1035        let syntax = syntax_map.snapshot();
1036
1037        BufferSnapshot {
1038            text,
1039            syntax,
1040            file: self.file.clone(),
1041            remote_selections: self.remote_selections.clone(),
1042            diagnostics: self.diagnostics.clone(),
1043            language: self.language.clone(),
1044            non_text_state_update_count: self.non_text_state_update_count,
1045        }
1046    }
1047
1048    pub fn branch(&mut self, cx: &mut Context<Self>) -> Entity<Self> {
1049        let this = cx.entity();
1050        cx.new(|cx| {
1051            let mut branch = Self {
1052                branch_state: Some(BufferBranchState {
1053                    base_buffer: this.clone(),
1054                    merged_operations: Default::default(),
1055                }),
1056                language: self.language.clone(),
1057                has_conflict: self.has_conflict,
1058                has_unsaved_edits: Cell::new(self.has_unsaved_edits.get_mut().clone()),
1059                _subscriptions: vec![cx.subscribe(&this, Self::on_base_buffer_event)],
1060                ..Self::build(self.text.branch(), self.file.clone(), self.capability())
1061            };
1062            if let Some(language_registry) = self.language_registry() {
1063                branch.set_language_registry(language_registry);
1064            }
1065
1066            // Reparse the branch buffer so that we get syntax highlighting immediately.
1067            branch.reparse(cx);
1068
1069            branch
1070        })
1071    }
1072
1073    pub fn preview_edits(
1074        &self,
1075        edits: Arc<[(Range<Anchor>, String)]>,
1076        cx: &App,
1077    ) -> Task<EditPreview> {
1078        let registry = self.language_registry();
1079        let language = self.language().cloned();
1080        let old_snapshot = self.text.snapshot();
1081        let mut branch_buffer = self.text.branch();
1082        let mut syntax_snapshot = self.syntax_map.lock().snapshot();
1083        cx.background_spawn(async move {
1084            if !edits.is_empty() {
1085                if let Some(language) = language.clone() {
1086                    syntax_snapshot.reparse(&old_snapshot, registry.clone(), language);
1087                }
1088
1089                branch_buffer.edit(edits.iter().cloned());
1090                let snapshot = branch_buffer.snapshot();
1091                syntax_snapshot.interpolate(&snapshot);
1092
1093                if let Some(language) = language {
1094                    syntax_snapshot.reparse(&snapshot, registry, language);
1095                }
1096            }
1097            EditPreview {
1098                old_snapshot,
1099                applied_edits_snapshot: branch_buffer.snapshot(),
1100                syntax_snapshot,
1101            }
1102        })
1103    }
1104
1105    /// Applies all of the changes in this buffer that intersect any of the
1106    /// given `ranges` to its base buffer.
1107    ///
1108    /// If `ranges` is empty, then all changes will be applied. This buffer must
1109    /// be a branch buffer to call this method.
1110    pub fn merge_into_base(&mut self, ranges: Vec<Range<usize>>, cx: &mut Context<Self>) {
1111        let Some(base_buffer) = self.base_buffer() else {
1112            debug_panic!("not a branch buffer");
1113            return;
1114        };
1115
1116        let mut ranges = if ranges.is_empty() {
1117            &[0..usize::MAX]
1118        } else {
1119            ranges.as_slice()
1120        }
1121        .into_iter()
1122        .peekable();
1123
1124        let mut edits = Vec::new();
1125        for edit in self.edits_since::<usize>(&base_buffer.read(cx).version()) {
1126            let mut is_included = false;
1127            while let Some(range) = ranges.peek() {
1128                if range.end < edit.new.start {
1129                    ranges.next().unwrap();
1130                } else {
1131                    if range.start <= edit.new.end {
1132                        is_included = true;
1133                    }
1134                    break;
1135                }
1136            }
1137
1138            if is_included {
1139                edits.push((
1140                    edit.old.clone(),
1141                    self.text_for_range(edit.new.clone()).collect::<String>(),
1142                ));
1143            }
1144        }
1145
1146        let operation = base_buffer.update(cx, |base_buffer, cx| {
1147            // cx.emit(BufferEvent::DiffBaseChanged);
1148            base_buffer.edit(edits, None, cx)
1149        });
1150
1151        if let Some(operation) = operation {
1152            if let Some(BufferBranchState {
1153                merged_operations, ..
1154            }) = &mut self.branch_state
1155            {
1156                merged_operations.push(operation);
1157            }
1158        }
1159    }
1160
1161    fn on_base_buffer_event(
1162        &mut self,
1163        _: Entity<Buffer>,
1164        event: &BufferEvent,
1165        cx: &mut Context<Self>,
1166    ) {
1167        let BufferEvent::Operation { operation, .. } = event else {
1168            return;
1169        };
1170        let Some(BufferBranchState {
1171            merged_operations, ..
1172        }) = &mut self.branch_state
1173        else {
1174            return;
1175        };
1176
1177        let mut operation_to_undo = None;
1178        if let Operation::Buffer(text::Operation::Edit(operation)) = &operation {
1179            if let Ok(ix) = merged_operations.binary_search(&operation.timestamp) {
1180                merged_operations.remove(ix);
1181                operation_to_undo = Some(operation.timestamp);
1182            }
1183        }
1184
1185        self.apply_ops([operation.clone()], cx);
1186
1187        if let Some(timestamp) = operation_to_undo {
1188            let counts = [(timestamp, u32::MAX)].into_iter().collect();
1189            self.undo_operations(counts, cx);
1190        }
1191    }
1192
1193    #[cfg(test)]
1194    pub(crate) fn as_text_snapshot(&self) -> &text::BufferSnapshot {
1195        &self.text
1196    }
1197
1198    /// Retrieve a snapshot of the buffer's raw text, without any
1199    /// language-related state like the syntax tree or diagnostics.
1200    pub fn text_snapshot(&self) -> text::BufferSnapshot {
1201        self.text.snapshot()
1202    }
1203
1204    /// The file associated with the buffer, if any.
1205    pub fn file(&self) -> Option<&Arc<dyn File>> {
1206        self.file.as_ref()
1207    }
1208
1209    /// The version of the buffer that was last saved or reloaded from disk.
1210    pub fn saved_version(&self) -> &clock::Global {
1211        &self.saved_version
1212    }
1213
1214    /// The mtime of the buffer's file when the buffer was last saved or reloaded from disk.
1215    pub fn saved_mtime(&self) -> Option<MTime> {
1216        self.saved_mtime
1217    }
1218
1219    /// Assign a language to the buffer.
1220    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut Context<Self>) {
1221        self.non_text_state_update_count += 1;
1222        self.syntax_map.lock().clear(&self.text);
1223        self.language = language;
1224        self.was_changed();
1225        self.reparse(cx);
1226        cx.emit(BufferEvent::LanguageChanged);
1227    }
1228
1229    /// Assign a language registry to the buffer. This allows the buffer to retrieve
1230    /// other languages if parts of the buffer are written in different languages.
1231    pub fn set_language_registry(&self, language_registry: Arc<LanguageRegistry>) {
1232        self.syntax_map
1233            .lock()
1234            .set_language_registry(language_registry);
1235    }
1236
1237    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
1238        self.syntax_map.lock().language_registry()
1239    }
1240
1241    /// Assign the buffer a new [`Capability`].
1242    pub fn set_capability(&mut self, capability: Capability, cx: &mut Context<Self>) {
1243        self.capability = capability;
1244        cx.emit(BufferEvent::CapabilityChanged)
1245    }
1246
1247    /// This method is called to signal that the buffer has been saved.
1248    pub fn did_save(
1249        &mut self,
1250        version: clock::Global,
1251        mtime: Option<MTime>,
1252        cx: &mut Context<Self>,
1253    ) {
1254        self.saved_version = version;
1255        self.has_unsaved_edits
1256            .set((self.saved_version().clone(), false));
1257        self.has_conflict = false;
1258        self.saved_mtime = mtime;
1259        self.was_changed();
1260        cx.emit(BufferEvent::Saved);
1261        cx.notify();
1262    }
1263
1264    /// This method is called to signal that the buffer has been discarded.
1265    pub fn discarded(&self, cx: &mut Context<Self>) {
1266        cx.emit(BufferEvent::Discarded);
1267        cx.notify();
1268    }
1269
1270    /// Reloads the contents of the buffer from disk.
1271    pub fn reload(&mut self, cx: &Context<Self>) -> oneshot::Receiver<Option<Transaction>> {
1272        let (tx, rx) = futures::channel::oneshot::channel();
1273        let prev_version = self.text.version();
1274        self.reload_task = Some(cx.spawn(async move |this, cx| {
1275            let Some((new_mtime, new_text)) = this.update(cx, |this, cx| {
1276                let file = this.file.as_ref()?.as_local()?;
1277
1278                Some((file.disk_state().mtime(), file.load(cx)))
1279            })?
1280            else {
1281                return Ok(());
1282            };
1283
1284            let new_text = new_text.await?;
1285            let diff = this
1286                .update(cx, |this, cx| this.diff(new_text.clone(), cx))?
1287                .await;
1288            this.update(cx, |this, cx| {
1289                if this.version() == diff.base_version {
1290                    this.finalize_last_transaction();
1291                    this.apply_diff(diff, cx);
1292                    tx.send(this.finalize_last_transaction().cloned()).ok();
1293                    this.has_conflict = false;
1294                    this.did_reload(this.version(), this.line_ending(), new_mtime, cx);
1295                } else {
1296                    if !diff.edits.is_empty()
1297                        || this
1298                            .edits_since::<usize>(&diff.base_version)
1299                            .next()
1300                            .is_some()
1301                    {
1302                        this.has_conflict = true;
1303                    }
1304
1305                    this.did_reload(prev_version, this.line_ending(), this.saved_mtime, cx);
1306                }
1307
1308                this.reload_task.take();
1309            })
1310        }));
1311        rx
1312    }
1313
1314    /// This method is called to signal that the buffer has been reloaded.
1315    pub fn did_reload(
1316        &mut self,
1317        version: clock::Global,
1318        line_ending: LineEnding,
1319        mtime: Option<MTime>,
1320        cx: &mut Context<Self>,
1321    ) {
1322        self.saved_version = version;
1323        self.has_unsaved_edits
1324            .set((self.saved_version.clone(), false));
1325        self.text.set_line_ending(line_ending);
1326        self.saved_mtime = mtime;
1327        cx.emit(BufferEvent::Reloaded);
1328        cx.notify();
1329    }
1330
1331    /// Updates the [`File`] backing this buffer. This should be called when
1332    /// the file has changed or has been deleted.
1333    pub fn file_updated(&mut self, new_file: Arc<dyn File>, cx: &mut Context<Self>) {
1334        let was_dirty = self.is_dirty();
1335        let mut file_changed = false;
1336
1337        if let Some(old_file) = self.file.as_ref() {
1338            if new_file.path() != old_file.path() {
1339                file_changed = true;
1340            }
1341
1342            let old_state = old_file.disk_state();
1343            let new_state = new_file.disk_state();
1344            if old_state != new_state {
1345                file_changed = true;
1346                if !was_dirty && matches!(new_state, DiskState::Present { .. }) {
1347                    cx.emit(BufferEvent::ReloadNeeded)
1348                }
1349            }
1350        } else {
1351            file_changed = true;
1352        };
1353
1354        self.file = Some(new_file);
1355        if file_changed {
1356            self.was_changed();
1357            self.non_text_state_update_count += 1;
1358            if was_dirty != self.is_dirty() {
1359                cx.emit(BufferEvent::DirtyChanged);
1360            }
1361            cx.emit(BufferEvent::FileHandleChanged);
1362            cx.notify();
1363        }
1364    }
1365
1366    pub fn base_buffer(&self) -> Option<Entity<Self>> {
1367        Some(self.branch_state.as_ref()?.base_buffer.clone())
1368    }
1369
1370    /// Returns the primary [`Language`] assigned to this [`Buffer`].
1371    pub fn language(&self) -> Option<&Arc<Language>> {
1372        self.language.as_ref()
1373    }
1374
1375    /// Returns the [`Language`] at the given location.
1376    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
1377        let offset = position.to_offset(self);
1378        self.syntax_map
1379            .lock()
1380            .layers_for_range(offset..offset, &self.text, false)
1381            .last()
1382            .map(|info| info.language.clone())
1383            .or_else(|| self.language.clone())
1384    }
1385
1386    /// Returns each [`Language`] for the active syntax layers at the given location.
1387    pub fn languages_at<D: ToOffset>(&self, position: D) -> Vec<Arc<Language>> {
1388        let offset = position.to_offset(self);
1389        let mut languages: Vec<Arc<Language>> = self
1390            .syntax_map
1391            .lock()
1392            .layers_for_range(offset..offset, &self.text, false)
1393            .map(|info| info.language.clone())
1394            .collect();
1395
1396        if languages.is_empty() {
1397            if let Some(buffer_language) = self.language() {
1398                languages.push(buffer_language.clone());
1399            }
1400        }
1401
1402        languages
1403    }
1404
1405    /// An integer version number that accounts for all updates besides
1406    /// the buffer's text itself (which is versioned via a version vector).
1407    pub fn non_text_state_update_count(&self) -> usize {
1408        self.non_text_state_update_count
1409    }
1410
1411    /// Whether the buffer is being parsed in the background.
1412    #[cfg(any(test, feature = "test-support"))]
1413    pub fn is_parsing(&self) -> bool {
1414        self.reparse.is_some()
1415    }
1416
1417    /// Indicates whether the buffer contains any regions that may be
1418    /// written in a language that hasn't been loaded yet.
1419    pub fn contains_unknown_injections(&self) -> bool {
1420        self.syntax_map.lock().contains_unknown_injections()
1421    }
1422
1423    #[cfg(test)]
1424    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
1425        self.sync_parse_timeout = timeout;
1426    }
1427
1428    /// Called after an edit to synchronize the buffer's main parse tree with
1429    /// the buffer's new underlying state.
1430    ///
1431    /// Locks the syntax map and interpolates the edits since the last reparse
1432    /// into the foreground syntax tree.
1433    ///
1434    /// Then takes a stable snapshot of the syntax map before unlocking it.
1435    /// The snapshot with the interpolated edits is sent to a background thread,
1436    /// where we ask Tree-sitter to perform an incremental parse.
1437    ///
1438    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
1439    /// waiting on the parse to complete. As soon as it completes, we proceed
1440    /// synchronously, unless a 1ms timeout elapses.
1441    ///
1442    /// If we time out waiting on the parse, we spawn a second task waiting
1443    /// until the parse does complete and return with the interpolated tree still
1444    /// in the foreground. When the background parse completes, call back into
1445    /// the main thread and assign the foreground parse state.
1446    ///
1447    /// If the buffer or grammar changed since the start of the background parse,
1448    /// initiate an additional reparse recursively. To avoid concurrent parses
1449    /// for the same buffer, we only initiate a new parse if we are not already
1450    /// parsing in the background.
1451    pub fn reparse(&mut self, cx: &mut Context<Self>) {
1452        if self.reparse.is_some() {
1453            return;
1454        }
1455        let language = if let Some(language) = self.language.clone() {
1456            language
1457        } else {
1458            return;
1459        };
1460
1461        let text = self.text_snapshot();
1462        let parsed_version = self.version();
1463
1464        let mut syntax_map = self.syntax_map.lock();
1465        syntax_map.interpolate(&text);
1466        let language_registry = syntax_map.language_registry();
1467        let mut syntax_snapshot = syntax_map.snapshot();
1468        drop(syntax_map);
1469
1470        let parse_task = cx.background_spawn({
1471            let language = language.clone();
1472            let language_registry = language_registry.clone();
1473            async move {
1474                syntax_snapshot.reparse(&text, language_registry, language);
1475                syntax_snapshot
1476            }
1477        });
1478
1479        self.parse_status.0.send(ParseStatus::Parsing).unwrap();
1480        match cx
1481            .background_executor()
1482            .block_with_timeout(self.sync_parse_timeout, parse_task)
1483        {
1484            Ok(new_syntax_snapshot) => {
1485                self.did_finish_parsing(new_syntax_snapshot, cx);
1486                self.reparse = None;
1487            }
1488            Err(parse_task) => {
1489                self.reparse = Some(cx.spawn(async move |this, cx| {
1490                    let new_syntax_map = parse_task.await;
1491                    this.update(cx, move |this, cx| {
1492                        let grammar_changed =
1493                            this.language.as_ref().map_or(true, |current_language| {
1494                                !Arc::ptr_eq(&language, current_language)
1495                            });
1496                        let language_registry_changed = new_syntax_map
1497                            .contains_unknown_injections()
1498                            && language_registry.map_or(false, |registry| {
1499                                registry.version() != new_syntax_map.language_registry_version()
1500                            });
1501                        let parse_again = language_registry_changed
1502                            || grammar_changed
1503                            || this.version.changed_since(&parsed_version);
1504                        this.did_finish_parsing(new_syntax_map, cx);
1505                        this.reparse = None;
1506                        if parse_again {
1507                            this.reparse(cx);
1508                        }
1509                    })
1510                    .ok();
1511                }));
1512            }
1513        }
1514    }
1515
1516    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut Context<Self>) {
1517        self.was_changed();
1518        self.non_text_state_update_count += 1;
1519        self.syntax_map.lock().did_parse(syntax_snapshot);
1520        self.request_autoindent(cx);
1521        self.parse_status.0.send(ParseStatus::Idle).unwrap();
1522        cx.emit(BufferEvent::Reparsed);
1523        cx.notify();
1524    }
1525
1526    pub fn parse_status(&self) -> watch::Receiver<ParseStatus> {
1527        self.parse_status.1.clone()
1528    }
1529
1530    /// Assign to the buffer a set of diagnostics created by a given language server.
1531    pub fn update_diagnostics(
1532        &mut self,
1533        server_id: LanguageServerId,
1534        diagnostics: DiagnosticSet,
1535        cx: &mut Context<Self>,
1536    ) {
1537        let lamport_timestamp = self.text.lamport_clock.tick();
1538        let op = Operation::UpdateDiagnostics {
1539            server_id,
1540            diagnostics: diagnostics.iter().cloned().collect(),
1541            lamport_timestamp,
1542        };
1543        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
1544        self.send_operation(op, true, cx);
1545    }
1546
1547    pub fn get_diagnostics(&self, server_id: LanguageServerId) -> Option<&DiagnosticSet> {
1548        let Ok(idx) = self.diagnostics.binary_search_by_key(&server_id, |v| v.0) else {
1549            return None;
1550        };
1551        Some(&self.diagnostics[idx].1)
1552    }
1553
1554    fn request_autoindent(&mut self, cx: &mut Context<Self>) {
1555        if let Some(indent_sizes) = self.compute_autoindents() {
1556            let indent_sizes = cx.background_spawn(indent_sizes);
1557            match cx
1558                .background_executor()
1559                .block_with_timeout(Duration::from_micros(500), indent_sizes)
1560            {
1561                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
1562                Err(indent_sizes) => {
1563                    self.pending_autoindent = Some(cx.spawn(async move |this, cx| {
1564                        let indent_sizes = indent_sizes.await;
1565                        this.update(cx, |this, cx| {
1566                            this.apply_autoindents(indent_sizes, cx);
1567                        })
1568                        .ok();
1569                    }));
1570                }
1571            }
1572        } else {
1573            self.autoindent_requests.clear();
1574        }
1575    }
1576
1577    fn compute_autoindents(
1578        &self,
1579    ) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>> + use<>> {
1580        let max_rows_between_yields = 100;
1581        let snapshot = self.snapshot();
1582        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
1583            return None;
1584        }
1585
1586        let autoindent_requests = self.autoindent_requests.clone();
1587        Some(async move {
1588            let mut indent_sizes = BTreeMap::<u32, (IndentSize, bool)>::new();
1589            for request in autoindent_requests {
1590                // Resolve each edited range to its row in the current buffer and in the
1591                // buffer before this batch of edits.
1592                let mut row_ranges = Vec::new();
1593                let mut old_to_new_rows = BTreeMap::new();
1594                let mut language_indent_sizes_by_new_row = Vec::new();
1595                for entry in &request.entries {
1596                    let position = entry.range.start;
1597                    let new_row = position.to_point(&snapshot).row;
1598                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
1599                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
1600
1601                    if !entry.first_line_is_new {
1602                        let old_row = position.to_point(&request.before_edit).row;
1603                        old_to_new_rows.insert(old_row, new_row);
1604                    }
1605                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
1606                }
1607
1608                // Build a map containing the suggested indentation for each of the edited lines
1609                // with respect to the state of the buffer before these edits. This map is keyed
1610                // by the rows for these lines in the current state of the buffer.
1611                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
1612                let old_edited_ranges =
1613                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
1614                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1615                let mut language_indent_size = IndentSize::default();
1616                for old_edited_range in old_edited_ranges {
1617                    let suggestions = request
1618                        .before_edit
1619                        .suggest_autoindents(old_edited_range.clone())
1620                        .into_iter()
1621                        .flatten();
1622                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1623                        if let Some(suggestion) = suggestion {
1624                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
1625
1626                            // Find the indent size based on the language for this row.
1627                            while let Some((row, size)) = language_indent_sizes.peek() {
1628                                if *row > new_row {
1629                                    break;
1630                                }
1631                                language_indent_size = *size;
1632                                language_indent_sizes.next();
1633                            }
1634
1635                            let suggested_indent = old_to_new_rows
1636                                .get(&suggestion.basis_row)
1637                                .and_then(|from_row| {
1638                                    Some(old_suggestions.get(from_row).copied()?.0)
1639                                })
1640                                .unwrap_or_else(|| {
1641                                    request
1642                                        .before_edit
1643                                        .indent_size_for_line(suggestion.basis_row)
1644                                })
1645                                .with_delta(suggestion.delta, language_indent_size);
1646                            old_suggestions
1647                                .insert(new_row, (suggested_indent, suggestion.within_error));
1648                        }
1649                    }
1650                    yield_now().await;
1651                }
1652
1653                // Compute new suggestions for each line, but only include them in the result
1654                // if they differ from the old suggestion for that line.
1655                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1656                let mut language_indent_size = IndentSize::default();
1657                for (row_range, original_indent_column) in row_ranges {
1658                    let new_edited_row_range = if request.is_block_mode {
1659                        row_range.start..row_range.start + 1
1660                    } else {
1661                        row_range.clone()
1662                    };
1663
1664                    let suggestions = snapshot
1665                        .suggest_autoindents(new_edited_row_range.clone())
1666                        .into_iter()
1667                        .flatten();
1668                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1669                        if let Some(suggestion) = suggestion {
1670                            // Find the indent size based on the language for this row.
1671                            while let Some((row, size)) = language_indent_sizes.peek() {
1672                                if *row > new_row {
1673                                    break;
1674                                }
1675                                language_indent_size = *size;
1676                                language_indent_sizes.next();
1677                            }
1678
1679                            let suggested_indent = indent_sizes
1680                                .get(&suggestion.basis_row)
1681                                .copied()
1682                                .map(|e| e.0)
1683                                .unwrap_or_else(|| {
1684                                    snapshot.indent_size_for_line(suggestion.basis_row)
1685                                })
1686                                .with_delta(suggestion.delta, language_indent_size);
1687
1688                            if old_suggestions.get(&new_row).map_or(
1689                                true,
1690                                |(old_indentation, was_within_error)| {
1691                                    suggested_indent != *old_indentation
1692                                        && (!suggestion.within_error || *was_within_error)
1693                                },
1694                            ) {
1695                                indent_sizes.insert(
1696                                    new_row,
1697                                    (suggested_indent, request.ignore_empty_lines),
1698                                );
1699                            }
1700                        }
1701                    }
1702
1703                    if let (true, Some(original_indent_column)) =
1704                        (request.is_block_mode, original_indent_column)
1705                    {
1706                        let new_indent =
1707                            if let Some((indent, _)) = indent_sizes.get(&row_range.start) {
1708                                *indent
1709                            } else {
1710                                snapshot.indent_size_for_line(row_range.start)
1711                            };
1712                        let delta = new_indent.len as i64 - original_indent_column as i64;
1713                        if delta != 0 {
1714                            for row in row_range.skip(1) {
1715                                indent_sizes.entry(row).or_insert_with(|| {
1716                                    let mut size = snapshot.indent_size_for_line(row);
1717                                    if size.kind == new_indent.kind {
1718                                        match delta.cmp(&0) {
1719                                            Ordering::Greater => size.len += delta as u32,
1720                                            Ordering::Less => {
1721                                                size.len = size.len.saturating_sub(-delta as u32)
1722                                            }
1723                                            Ordering::Equal => {}
1724                                        }
1725                                    }
1726                                    (size, request.ignore_empty_lines)
1727                                });
1728                            }
1729                        }
1730                    }
1731
1732                    yield_now().await;
1733                }
1734            }
1735
1736            indent_sizes
1737                .into_iter()
1738                .filter_map(|(row, (indent, ignore_empty_lines))| {
1739                    if ignore_empty_lines && snapshot.line_len(row) == 0 {
1740                        None
1741                    } else {
1742                        Some((row, indent))
1743                    }
1744                })
1745                .collect()
1746        })
1747    }
1748
1749    fn apply_autoindents(
1750        &mut self,
1751        indent_sizes: BTreeMap<u32, IndentSize>,
1752        cx: &mut Context<Self>,
1753    ) {
1754        self.autoindent_requests.clear();
1755
1756        let edits: Vec<_> = indent_sizes
1757            .into_iter()
1758            .filter_map(|(row, indent_size)| {
1759                let current_size = indent_size_for_line(self, row);
1760                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1761            })
1762            .collect();
1763
1764        let preserve_preview = self.preserve_preview();
1765        self.edit(edits, None, cx);
1766        if preserve_preview {
1767            self.refresh_preview();
1768        }
1769    }
1770
1771    /// Create a minimal edit that will cause the given row to be indented
1772    /// with the given size. After applying this edit, the length of the line
1773    /// will always be at least `new_size.len`.
1774    pub fn edit_for_indent_size_adjustment(
1775        row: u32,
1776        current_size: IndentSize,
1777        new_size: IndentSize,
1778    ) -> Option<(Range<Point>, String)> {
1779        if new_size.kind == current_size.kind {
1780            match new_size.len.cmp(&current_size.len) {
1781                Ordering::Greater => {
1782                    let point = Point::new(row, 0);
1783                    Some((
1784                        point..point,
1785                        iter::repeat(new_size.char())
1786                            .take((new_size.len - current_size.len) as usize)
1787                            .collect::<String>(),
1788                    ))
1789                }
1790
1791                Ordering::Less => Some((
1792                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1793                    String::new(),
1794                )),
1795
1796                Ordering::Equal => None,
1797            }
1798        } else {
1799            Some((
1800                Point::new(row, 0)..Point::new(row, current_size.len),
1801                iter::repeat(new_size.char())
1802                    .take(new_size.len as usize)
1803                    .collect::<String>(),
1804            ))
1805        }
1806    }
1807
1808    /// Spawns a background task that asynchronously computes a `Diff` between the buffer's text
1809    /// and the given new text.
1810    pub fn diff(&self, mut new_text: String, cx: &App) -> Task<Diff> {
1811        let old_text = self.as_rope().clone();
1812        let base_version = self.version();
1813        cx.background_executor()
1814            .spawn_labeled(*BUFFER_DIFF_TASK, async move {
1815                let old_text = old_text.to_string();
1816                let line_ending = LineEnding::detect(&new_text);
1817                LineEnding::normalize(&mut new_text);
1818                let edits = text_diff(&old_text, &new_text);
1819                Diff {
1820                    base_version,
1821                    line_ending,
1822                    edits,
1823                }
1824            })
1825    }
1826
1827    /// Spawns a background task that searches the buffer for any whitespace
1828    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1829    pub fn remove_trailing_whitespace(&self, cx: &App) -> Task<Diff> {
1830        let old_text = self.as_rope().clone();
1831        let line_ending = self.line_ending();
1832        let base_version = self.version();
1833        cx.background_spawn(async move {
1834            let ranges = trailing_whitespace_ranges(&old_text);
1835            let empty = Arc::<str>::from("");
1836            Diff {
1837                base_version,
1838                line_ending,
1839                edits: ranges
1840                    .into_iter()
1841                    .map(|range| (range, empty.clone()))
1842                    .collect(),
1843            }
1844        })
1845    }
1846
1847    /// Ensures that the buffer ends with a single newline character, and
1848    /// no other whitespace.
1849    pub fn ensure_final_newline(&mut self, cx: &mut Context<Self>) {
1850        let len = self.len();
1851        let mut offset = len;
1852        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1853            let non_whitespace_len = chunk
1854                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1855                .len();
1856            offset -= chunk.len();
1857            offset += non_whitespace_len;
1858            if non_whitespace_len != 0 {
1859                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1860                    return;
1861                }
1862                break;
1863            }
1864        }
1865        self.edit([(offset..len, "\n")], None, cx);
1866    }
1867
1868    /// Applies a diff to the buffer. If the buffer has changed since the given diff was
1869    /// calculated, then adjust the diff to account for those changes, and discard any
1870    /// parts of the diff that conflict with those changes.
1871    pub fn apply_diff(&mut self, diff: Diff, cx: &mut Context<Self>) -> Option<TransactionId> {
1872        let snapshot = self.snapshot();
1873        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1874        let mut delta = 0;
1875        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1876            while let Some(edit_since) = edits_since.peek() {
1877                // If the edit occurs after a diff hunk, then it does not
1878                // affect that hunk.
1879                if edit_since.old.start > range.end {
1880                    break;
1881                }
1882                // If the edit precedes the diff hunk, then adjust the hunk
1883                // to reflect the edit.
1884                else if edit_since.old.end < range.start {
1885                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1886                    edits_since.next();
1887                }
1888                // If the edit intersects a diff hunk, then discard that hunk.
1889                else {
1890                    return None;
1891                }
1892            }
1893
1894            let start = (range.start as i64 + delta) as usize;
1895            let end = (range.end as i64 + delta) as usize;
1896            Some((start..end, new_text))
1897        });
1898
1899        self.start_transaction();
1900        self.text.set_line_ending(diff.line_ending);
1901        self.edit(adjusted_edits, None, cx);
1902        self.end_transaction(cx)
1903    }
1904
1905    fn has_unsaved_edits(&self) -> bool {
1906        let (last_version, has_unsaved_edits) = self.has_unsaved_edits.take();
1907
1908        if last_version == self.version {
1909            self.has_unsaved_edits
1910                .set((last_version, has_unsaved_edits));
1911            return has_unsaved_edits;
1912        }
1913
1914        let has_edits = self.has_edits_since(&self.saved_version);
1915        self.has_unsaved_edits
1916            .set((self.version.clone(), has_edits));
1917        has_edits
1918    }
1919
1920    /// Checks if the buffer has unsaved changes.
1921    pub fn is_dirty(&self) -> bool {
1922        if self.capability == Capability::ReadOnly {
1923            return false;
1924        }
1925        if self.has_conflict {
1926            return true;
1927        }
1928        match self.file.as_ref().map(|f| f.disk_state()) {
1929            Some(DiskState::New) | Some(DiskState::Deleted) => {
1930                !self.is_empty() && self.has_unsaved_edits()
1931            }
1932            _ => self.has_unsaved_edits(),
1933        }
1934    }
1935
1936    /// Checks if the buffer and its file have both changed since the buffer
1937    /// was last saved or reloaded.
1938    pub fn has_conflict(&self) -> bool {
1939        if self.has_conflict {
1940            return true;
1941        }
1942        let Some(file) = self.file.as_ref() else {
1943            return false;
1944        };
1945        match file.disk_state() {
1946            DiskState::New => false,
1947            DiskState::Present { mtime } => match self.saved_mtime {
1948                Some(saved_mtime) => {
1949                    mtime.bad_is_greater_than(saved_mtime) && self.has_unsaved_edits()
1950                }
1951                None => true,
1952            },
1953            DiskState::Deleted => false,
1954        }
1955    }
1956
1957    /// Gets a [`Subscription`] that tracks all of the changes to the buffer's text.
1958    pub fn subscribe(&mut self) -> Subscription {
1959        self.text.subscribe()
1960    }
1961
1962    /// Adds a bit to the list of bits that are set when the buffer's text changes.
1963    ///
1964    /// This allows downstream code to check if the buffer's text has changed without
1965    /// waiting for an effect cycle, which would be required if using eents.
1966    pub fn record_changes(&mut self, bit: rc::Weak<Cell<bool>>) {
1967        if let Err(ix) = self
1968            .change_bits
1969            .binary_search_by_key(&rc::Weak::as_ptr(&bit), rc::Weak::as_ptr)
1970        {
1971            self.change_bits.insert(ix, bit);
1972        }
1973    }
1974
1975    fn was_changed(&mut self) {
1976        self.change_bits.retain(|change_bit| {
1977            change_bit.upgrade().map_or(false, |bit| {
1978                bit.replace(true);
1979                true
1980            })
1981        });
1982    }
1983
1984    /// Starts a transaction, if one is not already in-progress. When undoing or
1985    /// redoing edits, all of the edits performed within a transaction are undone
1986    /// or redone together.
1987    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1988        self.start_transaction_at(Instant::now())
1989    }
1990
1991    /// Starts a transaction, providing the current time. Subsequent transactions
1992    /// that occur within a short period of time will be grouped together. This
1993    /// is controlled by the buffer's undo grouping duration.
1994    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1995        self.transaction_depth += 1;
1996        if self.was_dirty_before_starting_transaction.is_none() {
1997            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1998        }
1999        self.text.start_transaction_at(now)
2000    }
2001
2002    /// Terminates the current transaction, if this is the outermost transaction.
2003    pub fn end_transaction(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2004        self.end_transaction_at(Instant::now(), cx)
2005    }
2006
2007    /// Terminates the current transaction, providing the current time. Subsequent transactions
2008    /// that occur within a short period of time will be grouped together. This
2009    /// is controlled by the buffer's undo grouping duration.
2010    pub fn end_transaction_at(
2011        &mut self,
2012        now: Instant,
2013        cx: &mut Context<Self>,
2014    ) -> Option<TransactionId> {
2015        assert!(self.transaction_depth > 0);
2016        self.transaction_depth -= 1;
2017        let was_dirty = if self.transaction_depth == 0 {
2018            self.was_dirty_before_starting_transaction.take().unwrap()
2019        } else {
2020            false
2021        };
2022        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
2023            self.did_edit(&start_version, was_dirty, cx);
2024            Some(transaction_id)
2025        } else {
2026            None
2027        }
2028    }
2029
2030    /// Manually add a transaction to the buffer's undo history.
2031    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
2032        self.text.push_transaction(transaction, now);
2033    }
2034
2035    /// Prevent the last transaction from being grouped with any subsequent transactions,
2036    /// even if they occur with the buffer's undo grouping duration.
2037    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
2038        self.text.finalize_last_transaction()
2039    }
2040
2041    /// Manually group all changes since a given transaction.
2042    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
2043        self.text.group_until_transaction(transaction_id);
2044    }
2045
2046    /// Manually remove a transaction from the buffer's undo history
2047    pub fn forget_transaction(&mut self, transaction_id: TransactionId) -> Option<Transaction> {
2048        self.text.forget_transaction(transaction_id)
2049    }
2050
2051    /// Retrieve a transaction from the buffer's undo history
2052    pub fn get_transaction(&self, transaction_id: TransactionId) -> Option<&Transaction> {
2053        self.text.get_transaction(transaction_id)
2054    }
2055
2056    /// Manually merge two transactions in the buffer's undo history.
2057    pub fn merge_transactions(&mut self, transaction: TransactionId, destination: TransactionId) {
2058        self.text.merge_transactions(transaction, destination);
2059    }
2060
2061    /// Waits for the buffer to receive operations with the given timestamps.
2062    pub fn wait_for_edits<It: IntoIterator<Item = clock::Lamport>>(
2063        &mut self,
2064        edit_ids: It,
2065    ) -> impl Future<Output = Result<()>> + use<It> {
2066        self.text.wait_for_edits(edit_ids)
2067    }
2068
2069    /// Waits for the buffer to receive the operations necessary for resolving the given anchors.
2070    pub fn wait_for_anchors<It: IntoIterator<Item = Anchor>>(
2071        &mut self,
2072        anchors: It,
2073    ) -> impl 'static + Future<Output = Result<()>> + use<It> {
2074        self.text.wait_for_anchors(anchors)
2075    }
2076
2077    /// Waits for the buffer to receive operations up to the given version.
2078    pub fn wait_for_version(
2079        &mut self,
2080        version: clock::Global,
2081    ) -> impl Future<Output = Result<()>> + use<> {
2082        self.text.wait_for_version(version)
2083    }
2084
2085    /// Forces all futures returned by [`Buffer::wait_for_version`], [`Buffer::wait_for_edits`], or
2086    /// [`Buffer::wait_for_version`] to resolve with an error.
2087    pub fn give_up_waiting(&mut self) {
2088        self.text.give_up_waiting();
2089    }
2090
2091    /// Stores a set of selections that should be broadcasted to all of the buffer's replicas.
2092    pub fn set_active_selections(
2093        &mut self,
2094        selections: Arc<[Selection<Anchor>]>,
2095        line_mode: bool,
2096        cursor_shape: CursorShape,
2097        cx: &mut Context<Self>,
2098    ) {
2099        let lamport_timestamp = self.text.lamport_clock.tick();
2100        self.remote_selections.insert(
2101            self.text.replica_id(),
2102            SelectionSet {
2103                selections: selections.clone(),
2104                lamport_timestamp,
2105                line_mode,
2106                cursor_shape,
2107            },
2108        );
2109        self.send_operation(
2110            Operation::UpdateSelections {
2111                selections,
2112                line_mode,
2113                lamport_timestamp,
2114                cursor_shape,
2115            },
2116            true,
2117            cx,
2118        );
2119        self.non_text_state_update_count += 1;
2120        cx.notify();
2121    }
2122
2123    /// Clears the selections, so that other replicas of the buffer do not see any selections for
2124    /// this replica.
2125    pub fn remove_active_selections(&mut self, cx: &mut Context<Self>) {
2126        if self
2127            .remote_selections
2128            .get(&self.text.replica_id())
2129            .map_or(true, |set| !set.selections.is_empty())
2130        {
2131            self.set_active_selections(Arc::default(), false, Default::default(), cx);
2132        }
2133    }
2134
2135    /// Replaces the buffer's entire text.
2136    pub fn set_text<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2137    where
2138        T: Into<Arc<str>>,
2139    {
2140        self.autoindent_requests.clear();
2141        self.edit([(0..self.len(), text)], None, cx)
2142    }
2143
2144    /// Applies the given edits to the buffer. Each edit is specified as a range of text to
2145    /// delete, and a string of text to insert at that location.
2146    ///
2147    /// If an [`AutoindentMode`] is provided, then the buffer will enqueue an auto-indent
2148    /// request for the edited ranges, which will be processed when the buffer finishes
2149    /// parsing.
2150    ///
2151    /// Parsing takes place at the end of a transaction, and may compute synchronously
2152    /// or asynchronously, depending on the changes.
2153    pub fn edit<I, S, T>(
2154        &mut self,
2155        edits_iter: I,
2156        autoindent_mode: Option<AutoindentMode>,
2157        cx: &mut Context<Self>,
2158    ) -> Option<clock::Lamport>
2159    where
2160        I: IntoIterator<Item = (Range<S>, T)>,
2161        S: ToOffset,
2162        T: Into<Arc<str>>,
2163    {
2164        // Skip invalid edits and coalesce contiguous ones.
2165        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
2166
2167        for (range, new_text) in edits_iter {
2168            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
2169
2170            if range.start > range.end {
2171                mem::swap(&mut range.start, &mut range.end);
2172            }
2173            let new_text = new_text.into();
2174            if !new_text.is_empty() || !range.is_empty() {
2175                if let Some((prev_range, prev_text)) = edits.last_mut() {
2176                    if prev_range.end >= range.start {
2177                        prev_range.end = cmp::max(prev_range.end, range.end);
2178                        *prev_text = format!("{prev_text}{new_text}").into();
2179                    } else {
2180                        edits.push((range, new_text));
2181                    }
2182                } else {
2183                    edits.push((range, new_text));
2184                }
2185            }
2186        }
2187        if edits.is_empty() {
2188            return None;
2189        }
2190
2191        self.start_transaction();
2192        self.pending_autoindent.take();
2193        let autoindent_request = autoindent_mode
2194            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
2195
2196        let edit_operation = self.text.edit(edits.iter().cloned());
2197        let edit_id = edit_operation.timestamp();
2198
2199        if let Some((before_edit, mode)) = autoindent_request {
2200            let mut delta = 0isize;
2201            let entries = edits
2202                .into_iter()
2203                .enumerate()
2204                .zip(&edit_operation.as_edit().unwrap().new_text)
2205                .map(|((ix, (range, _)), new_text)| {
2206                    let new_text_length = new_text.len();
2207                    let old_start = range.start.to_point(&before_edit);
2208                    let new_start = (delta + range.start as isize) as usize;
2209                    let range_len = range.end - range.start;
2210                    delta += new_text_length as isize - range_len as isize;
2211
2212                    // Decide what range of the insertion to auto-indent, and whether
2213                    // the first line of the insertion should be considered a newly-inserted line
2214                    // or an edit to an existing line.
2215                    let mut range_of_insertion_to_indent = 0..new_text_length;
2216                    let mut first_line_is_new = true;
2217
2218                    let old_line_start = before_edit.indent_size_for_line(old_start.row).len;
2219                    let old_line_end = before_edit.line_len(old_start.row);
2220
2221                    if old_start.column > old_line_start {
2222                        first_line_is_new = false;
2223                    }
2224
2225                    if !new_text.contains('\n')
2226                        && (old_start.column + (range_len as u32) < old_line_end
2227                            || old_line_end == old_line_start)
2228                    {
2229                        first_line_is_new = false;
2230                    }
2231
2232                    // When inserting text starting with a newline, avoid auto-indenting the
2233                    // previous line.
2234                    if new_text.starts_with('\n') {
2235                        range_of_insertion_to_indent.start += 1;
2236                        first_line_is_new = true;
2237                    }
2238
2239                    let mut original_indent_column = None;
2240                    if let AutoindentMode::Block {
2241                        original_indent_columns,
2242                    } = &mode
2243                    {
2244                        original_indent_column = Some(if new_text.starts_with('\n') {
2245                            indent_size_for_text(
2246                                new_text[range_of_insertion_to_indent.clone()].chars(),
2247                            )
2248                            .len
2249                        } else {
2250                            original_indent_columns
2251                                .get(ix)
2252                                .copied()
2253                                .flatten()
2254                                .unwrap_or_else(|| {
2255                                    indent_size_for_text(
2256                                        new_text[range_of_insertion_to_indent.clone()].chars(),
2257                                    )
2258                                    .len
2259                                })
2260                        });
2261
2262                        // Avoid auto-indenting the line after the edit.
2263                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
2264                            range_of_insertion_to_indent.end -= 1;
2265                        }
2266                    }
2267
2268                    AutoindentRequestEntry {
2269                        first_line_is_new,
2270                        original_indent_column,
2271                        indent_size: before_edit.language_indent_size_at(range.start, cx),
2272                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
2273                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
2274                    }
2275                })
2276                .collect();
2277
2278            self.autoindent_requests.push(Arc::new(AutoindentRequest {
2279                before_edit,
2280                entries,
2281                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
2282                ignore_empty_lines: false,
2283            }));
2284        }
2285
2286        self.end_transaction(cx);
2287        self.send_operation(Operation::Buffer(edit_operation), true, cx);
2288        Some(edit_id)
2289    }
2290
2291    fn did_edit(&mut self, old_version: &clock::Global, was_dirty: bool, cx: &mut Context<Self>) {
2292        self.was_changed();
2293
2294        if self.edits_since::<usize>(old_version).next().is_none() {
2295            return;
2296        }
2297
2298        self.reparse(cx);
2299        cx.emit(BufferEvent::Edited);
2300        if was_dirty != self.is_dirty() {
2301            cx.emit(BufferEvent::DirtyChanged);
2302        }
2303        cx.notify();
2304    }
2305
2306    pub fn autoindent_ranges<I, T>(&mut self, ranges: I, cx: &mut Context<Self>)
2307    where
2308        I: IntoIterator<Item = Range<T>>,
2309        T: ToOffset + Copy,
2310    {
2311        let before_edit = self.snapshot();
2312        let entries = ranges
2313            .into_iter()
2314            .map(|range| AutoindentRequestEntry {
2315                range: before_edit.anchor_before(range.start)..before_edit.anchor_after(range.end),
2316                first_line_is_new: true,
2317                indent_size: before_edit.language_indent_size_at(range.start, cx),
2318                original_indent_column: None,
2319            })
2320            .collect();
2321        self.autoindent_requests.push(Arc::new(AutoindentRequest {
2322            before_edit,
2323            entries,
2324            is_block_mode: false,
2325            ignore_empty_lines: true,
2326        }));
2327        self.request_autoindent(cx);
2328    }
2329
2330    // Inserts newlines at the given position to create an empty line, returning the start of the new line.
2331    // You can also request the insertion of empty lines above and below the line starting at the returned point.
2332    pub fn insert_empty_line(
2333        &mut self,
2334        position: impl ToPoint,
2335        space_above: bool,
2336        space_below: bool,
2337        cx: &mut Context<Self>,
2338    ) -> Point {
2339        let mut position = position.to_point(self);
2340
2341        self.start_transaction();
2342
2343        self.edit(
2344            [(position..position, "\n")],
2345            Some(AutoindentMode::EachLine),
2346            cx,
2347        );
2348
2349        if position.column > 0 {
2350            position += Point::new(1, 0);
2351        }
2352
2353        if !self.is_line_blank(position.row) {
2354            self.edit(
2355                [(position..position, "\n")],
2356                Some(AutoindentMode::EachLine),
2357                cx,
2358            );
2359        }
2360
2361        if space_above && position.row > 0 && !self.is_line_blank(position.row - 1) {
2362            self.edit(
2363                [(position..position, "\n")],
2364                Some(AutoindentMode::EachLine),
2365                cx,
2366            );
2367            position.row += 1;
2368        }
2369
2370        if space_below
2371            && (position.row == self.max_point().row || !self.is_line_blank(position.row + 1))
2372        {
2373            self.edit(
2374                [(position..position, "\n")],
2375                Some(AutoindentMode::EachLine),
2376                cx,
2377            );
2378        }
2379
2380        self.end_transaction(cx);
2381
2382        position
2383    }
2384
2385    /// Applies the given remote operations to the buffer.
2386    pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I, cx: &mut Context<Self>) {
2387        self.pending_autoindent.take();
2388        let was_dirty = self.is_dirty();
2389        let old_version = self.version.clone();
2390        let mut deferred_ops = Vec::new();
2391        let buffer_ops = ops
2392            .into_iter()
2393            .filter_map(|op| match op {
2394                Operation::Buffer(op) => Some(op),
2395                _ => {
2396                    if self.can_apply_op(&op) {
2397                        self.apply_op(op, cx);
2398                    } else {
2399                        deferred_ops.push(op);
2400                    }
2401                    None
2402                }
2403            })
2404            .collect::<Vec<_>>();
2405        for operation in buffer_ops.iter() {
2406            self.send_operation(Operation::Buffer(operation.clone()), false, cx);
2407        }
2408        self.text.apply_ops(buffer_ops);
2409        self.deferred_ops.insert(deferred_ops);
2410        self.flush_deferred_ops(cx);
2411        self.did_edit(&old_version, was_dirty, cx);
2412        // Notify independently of whether the buffer was edited as the operations could include a
2413        // selection update.
2414        cx.notify();
2415    }
2416
2417    fn flush_deferred_ops(&mut self, cx: &mut Context<Self>) {
2418        let mut deferred_ops = Vec::new();
2419        for op in self.deferred_ops.drain().iter().cloned() {
2420            if self.can_apply_op(&op) {
2421                self.apply_op(op, cx);
2422            } else {
2423                deferred_ops.push(op);
2424            }
2425        }
2426        self.deferred_ops.insert(deferred_ops);
2427    }
2428
2429    pub fn has_deferred_ops(&self) -> bool {
2430        !self.deferred_ops.is_empty() || self.text.has_deferred_ops()
2431    }
2432
2433    fn can_apply_op(&self, operation: &Operation) -> bool {
2434        match operation {
2435            Operation::Buffer(_) => {
2436                unreachable!("buffer operations should never be applied at this layer")
2437            }
2438            Operation::UpdateDiagnostics {
2439                diagnostics: diagnostic_set,
2440                ..
2441            } => diagnostic_set.iter().all(|diagnostic| {
2442                self.text.can_resolve(&diagnostic.range.start)
2443                    && self.text.can_resolve(&diagnostic.range.end)
2444            }),
2445            Operation::UpdateSelections { selections, .. } => selections
2446                .iter()
2447                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
2448            Operation::UpdateCompletionTriggers { .. } => true,
2449        }
2450    }
2451
2452    fn apply_op(&mut self, operation: Operation, cx: &mut Context<Self>) {
2453        match operation {
2454            Operation::Buffer(_) => {
2455                unreachable!("buffer operations should never be applied at this layer")
2456            }
2457            Operation::UpdateDiagnostics {
2458                server_id,
2459                diagnostics: diagnostic_set,
2460                lamport_timestamp,
2461            } => {
2462                let snapshot = self.snapshot();
2463                self.apply_diagnostic_update(
2464                    server_id,
2465                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
2466                    lamport_timestamp,
2467                    cx,
2468                );
2469            }
2470            Operation::UpdateSelections {
2471                selections,
2472                lamport_timestamp,
2473                line_mode,
2474                cursor_shape,
2475            } => {
2476                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
2477                    if set.lamport_timestamp > lamport_timestamp {
2478                        return;
2479                    }
2480                }
2481
2482                self.remote_selections.insert(
2483                    lamport_timestamp.replica_id,
2484                    SelectionSet {
2485                        selections,
2486                        lamport_timestamp,
2487                        line_mode,
2488                        cursor_shape,
2489                    },
2490                );
2491                self.text.lamport_clock.observe(lamport_timestamp);
2492                self.non_text_state_update_count += 1;
2493            }
2494            Operation::UpdateCompletionTriggers {
2495                triggers,
2496                lamport_timestamp,
2497                server_id,
2498            } => {
2499                if triggers.is_empty() {
2500                    self.completion_triggers_per_language_server
2501                        .remove(&server_id);
2502                    self.completion_triggers = self
2503                        .completion_triggers_per_language_server
2504                        .values()
2505                        .flat_map(|triggers| triggers.into_iter().cloned())
2506                        .collect();
2507                } else {
2508                    self.completion_triggers_per_language_server
2509                        .insert(server_id, triggers.iter().cloned().collect());
2510                    self.completion_triggers.extend(triggers);
2511                }
2512                self.text.lamport_clock.observe(lamport_timestamp);
2513            }
2514        }
2515    }
2516
2517    fn apply_diagnostic_update(
2518        &mut self,
2519        server_id: LanguageServerId,
2520        diagnostics: DiagnosticSet,
2521        lamport_timestamp: clock::Lamport,
2522        cx: &mut Context<Self>,
2523    ) {
2524        if lamport_timestamp > self.diagnostics_timestamp {
2525            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
2526            if diagnostics.is_empty() {
2527                if let Ok(ix) = ix {
2528                    self.diagnostics.remove(ix);
2529                }
2530            } else {
2531                match ix {
2532                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
2533                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
2534                };
2535            }
2536            self.diagnostics_timestamp = lamport_timestamp;
2537            self.non_text_state_update_count += 1;
2538            self.text.lamport_clock.observe(lamport_timestamp);
2539            cx.notify();
2540            cx.emit(BufferEvent::DiagnosticsUpdated);
2541        }
2542    }
2543
2544    fn send_operation(&mut self, operation: Operation, is_local: bool, cx: &mut Context<Self>) {
2545        self.was_changed();
2546        cx.emit(BufferEvent::Operation {
2547            operation,
2548            is_local,
2549        });
2550    }
2551
2552    /// Removes the selections for a given peer.
2553    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut Context<Self>) {
2554        self.remote_selections.remove(&replica_id);
2555        cx.notify();
2556    }
2557
2558    /// Undoes the most recent transaction.
2559    pub fn undo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2560        let was_dirty = self.is_dirty();
2561        let old_version = self.version.clone();
2562
2563        if let Some((transaction_id, operation)) = self.text.undo() {
2564            self.send_operation(Operation::Buffer(operation), true, cx);
2565            self.did_edit(&old_version, was_dirty, cx);
2566            Some(transaction_id)
2567        } else {
2568            None
2569        }
2570    }
2571
2572    /// Manually undoes a specific transaction in the buffer's undo history.
2573    pub fn undo_transaction(
2574        &mut self,
2575        transaction_id: TransactionId,
2576        cx: &mut Context<Self>,
2577    ) -> bool {
2578        let was_dirty = self.is_dirty();
2579        let old_version = self.version.clone();
2580        if let Some(operation) = self.text.undo_transaction(transaction_id) {
2581            self.send_operation(Operation::Buffer(operation), true, cx);
2582            self.did_edit(&old_version, was_dirty, cx);
2583            true
2584        } else {
2585            false
2586        }
2587    }
2588
2589    /// Manually undoes all changes after a given transaction in the buffer's undo history.
2590    pub fn undo_to_transaction(
2591        &mut self,
2592        transaction_id: TransactionId,
2593        cx: &mut Context<Self>,
2594    ) -> bool {
2595        let was_dirty = self.is_dirty();
2596        let old_version = self.version.clone();
2597
2598        let operations = self.text.undo_to_transaction(transaction_id);
2599        let undone = !operations.is_empty();
2600        for operation in operations {
2601            self.send_operation(Operation::Buffer(operation), true, cx);
2602        }
2603        if undone {
2604            self.did_edit(&old_version, was_dirty, cx)
2605        }
2606        undone
2607    }
2608
2609    pub fn undo_operations(&mut self, counts: HashMap<Lamport, u32>, cx: &mut Context<Buffer>) {
2610        let was_dirty = self.is_dirty();
2611        let operation = self.text.undo_operations(counts);
2612        let old_version = self.version.clone();
2613        self.send_operation(Operation::Buffer(operation), true, cx);
2614        self.did_edit(&old_version, was_dirty, cx);
2615    }
2616
2617    /// Manually redoes a specific transaction in the buffer's redo history.
2618    pub fn redo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2619        let was_dirty = self.is_dirty();
2620        let old_version = self.version.clone();
2621
2622        if let Some((transaction_id, operation)) = self.text.redo() {
2623            self.send_operation(Operation::Buffer(operation), true, cx);
2624            self.did_edit(&old_version, was_dirty, cx);
2625            Some(transaction_id)
2626        } else {
2627            None
2628        }
2629    }
2630
2631    /// Manually undoes all changes until a given transaction in the buffer's redo history.
2632    pub fn redo_to_transaction(
2633        &mut self,
2634        transaction_id: TransactionId,
2635        cx: &mut Context<Self>,
2636    ) -> bool {
2637        let was_dirty = self.is_dirty();
2638        let old_version = self.version.clone();
2639
2640        let operations = self.text.redo_to_transaction(transaction_id);
2641        let redone = !operations.is_empty();
2642        for operation in operations {
2643            self.send_operation(Operation::Buffer(operation), true, cx);
2644        }
2645        if redone {
2646            self.did_edit(&old_version, was_dirty, cx)
2647        }
2648        redone
2649    }
2650
2651    /// Override current completion triggers with the user-provided completion triggers.
2652    pub fn set_completion_triggers(
2653        &mut self,
2654        server_id: LanguageServerId,
2655        triggers: BTreeSet<String>,
2656        cx: &mut Context<Self>,
2657    ) {
2658        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
2659        if triggers.is_empty() {
2660            self.completion_triggers_per_language_server
2661                .remove(&server_id);
2662            self.completion_triggers = self
2663                .completion_triggers_per_language_server
2664                .values()
2665                .flat_map(|triggers| triggers.into_iter().cloned())
2666                .collect();
2667        } else {
2668            self.completion_triggers_per_language_server
2669                .insert(server_id, triggers.clone());
2670            self.completion_triggers.extend(triggers.iter().cloned());
2671        }
2672        self.send_operation(
2673            Operation::UpdateCompletionTriggers {
2674                triggers: triggers.iter().cloned().collect(),
2675                lamport_timestamp: self.completion_triggers_timestamp,
2676                server_id,
2677            },
2678            true,
2679            cx,
2680        );
2681        cx.notify();
2682    }
2683
2684    /// Returns a list of strings which trigger a completion menu for this language.
2685    /// Usually this is driven by LSP server which returns a list of trigger characters for completions.
2686    pub fn completion_triggers(&self) -> &BTreeSet<String> {
2687        &self.completion_triggers
2688    }
2689
2690    /// Call this directly after performing edits to prevent the preview tab
2691    /// from being dismissed by those edits. It causes `should_dismiss_preview`
2692    /// to return false until there are additional edits.
2693    pub fn refresh_preview(&mut self) {
2694        self.preview_version = self.version.clone();
2695    }
2696
2697    /// Whether we should preserve the preview status of a tab containing this buffer.
2698    pub fn preserve_preview(&self) -> bool {
2699        !self.has_edits_since(&self.preview_version)
2700    }
2701}
2702
2703#[doc(hidden)]
2704#[cfg(any(test, feature = "test-support"))]
2705impl Buffer {
2706    pub fn edit_via_marked_text(
2707        &mut self,
2708        marked_string: &str,
2709        autoindent_mode: Option<AutoindentMode>,
2710        cx: &mut Context<Self>,
2711    ) {
2712        let edits = self.edits_for_marked_text(marked_string);
2713        self.edit(edits, autoindent_mode, cx);
2714    }
2715
2716    pub fn set_group_interval(&mut self, group_interval: Duration) {
2717        self.text.set_group_interval(group_interval);
2718    }
2719
2720    pub fn randomly_edit<T>(&mut self, rng: &mut T, old_range_count: usize, cx: &mut Context<Self>)
2721    where
2722        T: rand::Rng,
2723    {
2724        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
2725        let mut last_end = None;
2726        for _ in 0..old_range_count {
2727            if last_end.map_or(false, |last_end| last_end >= self.len()) {
2728                break;
2729            }
2730
2731            let new_start = last_end.map_or(0, |last_end| last_end + 1);
2732            let mut range = self.random_byte_range(new_start, rng);
2733            if rng.gen_bool(0.2) {
2734                mem::swap(&mut range.start, &mut range.end);
2735            }
2736            last_end = Some(range.end);
2737
2738            let new_text_len = rng.gen_range(0..10);
2739            let mut new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
2740            new_text = new_text.to_uppercase();
2741
2742            edits.push((range, new_text));
2743        }
2744        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
2745        self.edit(edits, None, cx);
2746    }
2747
2748    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut Context<Self>) {
2749        let was_dirty = self.is_dirty();
2750        let old_version = self.version.clone();
2751
2752        let ops = self.text.randomly_undo_redo(rng);
2753        if !ops.is_empty() {
2754            for op in ops {
2755                self.send_operation(Operation::Buffer(op), true, cx);
2756                self.did_edit(&old_version, was_dirty, cx);
2757            }
2758        }
2759    }
2760}
2761
2762impl EventEmitter<BufferEvent> for Buffer {}
2763
2764impl Deref for Buffer {
2765    type Target = TextBuffer;
2766
2767    fn deref(&self) -> &Self::Target {
2768        &self.text
2769    }
2770}
2771
2772impl BufferSnapshot {
2773    /// Returns [`IndentSize`] for a given line that respects user settings and
2774    /// language preferences.
2775    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
2776        indent_size_for_line(self, row)
2777    }
2778
2779    /// Returns [`IndentSize`] for a given position that respects user settings
2780    /// and language preferences.
2781    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &App) -> IndentSize {
2782        let settings = language_settings(
2783            self.language_at(position).map(|l| l.name()),
2784            self.file(),
2785            cx,
2786        );
2787        if settings.hard_tabs {
2788            IndentSize::tab()
2789        } else {
2790            IndentSize::spaces(settings.tab_size.get())
2791        }
2792    }
2793
2794    /// Retrieve the suggested indent size for all of the given rows. The unit of indentation
2795    /// is passed in as `single_indent_size`.
2796    pub fn suggested_indents(
2797        &self,
2798        rows: impl Iterator<Item = u32>,
2799        single_indent_size: IndentSize,
2800    ) -> BTreeMap<u32, IndentSize> {
2801        let mut result = BTreeMap::new();
2802
2803        for row_range in contiguous_ranges(rows, 10) {
2804            let suggestions = match self.suggest_autoindents(row_range.clone()) {
2805                Some(suggestions) => suggestions,
2806                _ => break,
2807            };
2808
2809            for (row, suggestion) in row_range.zip(suggestions) {
2810                let indent_size = if let Some(suggestion) = suggestion {
2811                    result
2812                        .get(&suggestion.basis_row)
2813                        .copied()
2814                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
2815                        .with_delta(suggestion.delta, single_indent_size)
2816                } else {
2817                    self.indent_size_for_line(row)
2818                };
2819
2820                result.insert(row, indent_size);
2821            }
2822        }
2823
2824        result
2825    }
2826
2827    fn suggest_autoindents(
2828        &self,
2829        row_range: Range<u32>,
2830    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
2831        let config = &self.language.as_ref()?.config;
2832        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
2833
2834        // Find the suggested indentation ranges based on the syntax tree.
2835        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
2836        let end = Point::new(row_range.end, 0);
2837        let range = (start..end).to_offset(&self.text);
2838        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2839            Some(&grammar.indents_config.as_ref()?.query)
2840        });
2841        let indent_configs = matches
2842            .grammars()
2843            .iter()
2844            .map(|grammar| grammar.indents_config.as_ref().unwrap())
2845            .collect::<Vec<_>>();
2846
2847        let mut indent_ranges = Vec::<Range<Point>>::new();
2848        let mut outdent_positions = Vec::<Point>::new();
2849        while let Some(mat) = matches.peek() {
2850            let mut start: Option<Point> = None;
2851            let mut end: Option<Point> = None;
2852
2853            let config = &indent_configs[mat.grammar_index];
2854            for capture in mat.captures {
2855                if capture.index == config.indent_capture_ix {
2856                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
2857                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
2858                } else if Some(capture.index) == config.start_capture_ix {
2859                    start = Some(Point::from_ts_point(capture.node.end_position()));
2860                } else if Some(capture.index) == config.end_capture_ix {
2861                    end = Some(Point::from_ts_point(capture.node.start_position()));
2862                } else if Some(capture.index) == config.outdent_capture_ix {
2863                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
2864                }
2865            }
2866
2867            matches.advance();
2868            if let Some((start, end)) = start.zip(end) {
2869                if start.row == end.row {
2870                    continue;
2871                }
2872
2873                let range = start..end;
2874                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
2875                    Err(ix) => indent_ranges.insert(ix, range),
2876                    Ok(ix) => {
2877                        let prev_range = &mut indent_ranges[ix];
2878                        prev_range.end = prev_range.end.max(range.end);
2879                    }
2880                }
2881            }
2882        }
2883
2884        let mut error_ranges = Vec::<Range<Point>>::new();
2885        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2886            grammar.error_query.as_ref()
2887        });
2888        while let Some(mat) = matches.peek() {
2889            let node = mat.captures[0].node;
2890            let start = Point::from_ts_point(node.start_position());
2891            let end = Point::from_ts_point(node.end_position());
2892            let range = start..end;
2893            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
2894                Ok(ix) | Err(ix) => ix,
2895            };
2896            let mut end_ix = ix;
2897            while let Some(existing_range) = error_ranges.get(end_ix) {
2898                if existing_range.end < end {
2899                    end_ix += 1;
2900                } else {
2901                    break;
2902                }
2903            }
2904            error_ranges.splice(ix..end_ix, [range]);
2905            matches.advance();
2906        }
2907
2908        outdent_positions.sort();
2909        for outdent_position in outdent_positions {
2910            // find the innermost indent range containing this outdent_position
2911            // set its end to the outdent position
2912            if let Some(range_to_truncate) = indent_ranges
2913                .iter_mut()
2914                .filter(|indent_range| indent_range.contains(&outdent_position))
2915                .next_back()
2916            {
2917                range_to_truncate.end = outdent_position;
2918            }
2919        }
2920
2921        // Find the suggested indentation increases and decreased based on regexes.
2922        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
2923        self.for_each_line(
2924            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
2925                ..Point::new(row_range.end, 0),
2926            |row, line| {
2927                if config
2928                    .decrease_indent_pattern
2929                    .as_ref()
2930                    .map_or(false, |regex| regex.is_match(line))
2931                {
2932                    indent_change_rows.push((row, Ordering::Less));
2933                }
2934                if config
2935                    .increase_indent_pattern
2936                    .as_ref()
2937                    .map_or(false, |regex| regex.is_match(line))
2938                {
2939                    indent_change_rows.push((row + 1, Ordering::Greater));
2940                }
2941            },
2942        );
2943
2944        let mut indent_changes = indent_change_rows.into_iter().peekable();
2945        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
2946            prev_non_blank_row.unwrap_or(0)
2947        } else {
2948            row_range.start.saturating_sub(1)
2949        };
2950        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
2951        Some(row_range.map(move |row| {
2952            let row_start = Point::new(row, self.indent_size_for_line(row).len);
2953
2954            let mut indent_from_prev_row = false;
2955            let mut outdent_from_prev_row = false;
2956            let mut outdent_to_row = u32::MAX;
2957            let mut from_regex = false;
2958
2959            while let Some((indent_row, delta)) = indent_changes.peek() {
2960                match indent_row.cmp(&row) {
2961                    Ordering::Equal => match delta {
2962                        Ordering::Less => {
2963                            from_regex = true;
2964                            outdent_from_prev_row = true
2965                        }
2966                        Ordering::Greater => {
2967                            indent_from_prev_row = true;
2968                            from_regex = true
2969                        }
2970                        _ => {}
2971                    },
2972
2973                    Ordering::Greater => break,
2974                    Ordering::Less => {}
2975                }
2976
2977                indent_changes.next();
2978            }
2979
2980            for range in &indent_ranges {
2981                if range.start.row >= row {
2982                    break;
2983                }
2984                if range.start.row == prev_row && range.end > row_start {
2985                    indent_from_prev_row = true;
2986                }
2987                if range.end > prev_row_start && range.end <= row_start {
2988                    outdent_to_row = outdent_to_row.min(range.start.row);
2989                }
2990            }
2991
2992            let within_error = error_ranges
2993                .iter()
2994                .any(|e| e.start.row < row && e.end > row_start);
2995
2996            let suggestion = if outdent_to_row == prev_row
2997                || (outdent_from_prev_row && indent_from_prev_row)
2998            {
2999                Some(IndentSuggestion {
3000                    basis_row: prev_row,
3001                    delta: Ordering::Equal,
3002                    within_error: within_error && !from_regex,
3003                })
3004            } else if indent_from_prev_row {
3005                Some(IndentSuggestion {
3006                    basis_row: prev_row,
3007                    delta: Ordering::Greater,
3008                    within_error: within_error && !from_regex,
3009                })
3010            } else if outdent_to_row < prev_row {
3011                Some(IndentSuggestion {
3012                    basis_row: outdent_to_row,
3013                    delta: Ordering::Equal,
3014                    within_error: within_error && !from_regex,
3015                })
3016            } else if outdent_from_prev_row {
3017                Some(IndentSuggestion {
3018                    basis_row: prev_row,
3019                    delta: Ordering::Less,
3020                    within_error: within_error && !from_regex,
3021                })
3022            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
3023            {
3024                Some(IndentSuggestion {
3025                    basis_row: prev_row,
3026                    delta: Ordering::Equal,
3027                    within_error: within_error && !from_regex,
3028                })
3029            } else {
3030                None
3031            };
3032
3033            prev_row = row;
3034            prev_row_start = row_start;
3035            suggestion
3036        }))
3037    }
3038
3039    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
3040        while row > 0 {
3041            row -= 1;
3042            if !self.is_line_blank(row) {
3043                return Some(row);
3044            }
3045        }
3046        None
3047    }
3048
3049    fn get_highlights(&self, range: Range<usize>) -> (SyntaxMapCaptures, Vec<HighlightMap>) {
3050        let captures = self.syntax.captures(range, &self.text, |grammar| {
3051            grammar.highlights_query.as_ref()
3052        });
3053        let highlight_maps = captures
3054            .grammars()
3055            .iter()
3056            .map(|grammar| grammar.highlight_map())
3057            .collect();
3058        (captures, highlight_maps)
3059    }
3060
3061    /// Iterates over chunks of text in the given range of the buffer. Text is chunked
3062    /// in an arbitrary way due to being stored in a [`Rope`](text::Rope). The text is also
3063    /// returned in chunks where each chunk has a single syntax highlighting style and
3064    /// diagnostic status.
3065    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
3066        let range = range.start.to_offset(self)..range.end.to_offset(self);
3067
3068        let mut syntax = None;
3069        if language_aware {
3070            syntax = Some(self.get_highlights(range.clone()));
3071        }
3072        // We want to look at diagnostic spans only when iterating over language-annotated chunks.
3073        let diagnostics = language_aware;
3074        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostics, Some(self))
3075    }
3076
3077    pub fn highlighted_text_for_range<T: ToOffset>(
3078        &self,
3079        range: Range<T>,
3080        override_style: Option<HighlightStyle>,
3081        syntax_theme: &SyntaxTheme,
3082    ) -> HighlightedText {
3083        HighlightedText::from_buffer_range(
3084            range,
3085            &self.text,
3086            &self.syntax,
3087            override_style,
3088            syntax_theme,
3089        )
3090    }
3091
3092    /// Invokes the given callback for each line of text in the given range of the buffer.
3093    /// Uses callback to avoid allocating a string for each line.
3094    fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
3095        let mut line = String::new();
3096        let mut row = range.start.row;
3097        for chunk in self
3098            .as_rope()
3099            .chunks_in_range(range.to_offset(self))
3100            .chain(["\n"])
3101        {
3102            for (newline_ix, text) in chunk.split('\n').enumerate() {
3103                if newline_ix > 0 {
3104                    callback(row, &line);
3105                    row += 1;
3106                    line.clear();
3107                }
3108                line.push_str(text);
3109            }
3110        }
3111    }
3112
3113    /// Iterates over every [`SyntaxLayer`] in the buffer.
3114    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayer> + '_ {
3115        self.syntax
3116            .layers_for_range(0..self.len(), &self.text, true)
3117    }
3118
3119    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayer> {
3120        let offset = position.to_offset(self);
3121        self.syntax
3122            .layers_for_range(offset..offset, &self.text, false)
3123            .filter(|l| l.node().end_byte() > offset)
3124            .last()
3125    }
3126
3127    pub fn smallest_syntax_layer_containing<D: ToOffset>(
3128        &self,
3129        range: Range<D>,
3130    ) -> Option<SyntaxLayer> {
3131        let range = range.to_offset(self);
3132        return self
3133            .syntax
3134            .layers_for_range(range, &self.text, false)
3135            .max_by(|a, b| {
3136                if a.depth != b.depth {
3137                    a.depth.cmp(&b.depth)
3138                } else if a.offset.0 != b.offset.0 {
3139                    a.offset.0.cmp(&b.offset.0)
3140                } else {
3141                    a.node().end_byte().cmp(&b.node().end_byte()).reverse()
3142                }
3143            });
3144    }
3145
3146    /// Returns the main [`Language`].
3147    pub fn language(&self) -> Option<&Arc<Language>> {
3148        self.language.as_ref()
3149    }
3150
3151    /// Returns the [`Language`] at the given location.
3152    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
3153        self.syntax_layer_at(position)
3154            .map(|info| info.language)
3155            .or(self.language.as_ref())
3156    }
3157
3158    /// Returns the settings for the language at the given location.
3159    pub fn settings_at<'a, D: ToOffset>(
3160        &'a self,
3161        position: D,
3162        cx: &'a App,
3163    ) -> Cow<'a, LanguageSettings> {
3164        language_settings(
3165            self.language_at(position).map(|l| l.name()),
3166            self.file.as_ref(),
3167            cx,
3168        )
3169    }
3170
3171    pub fn char_classifier_at<T: ToOffset>(&self, point: T) -> CharClassifier {
3172        CharClassifier::new(self.language_scope_at(point))
3173    }
3174
3175    /// Returns the [`LanguageScope`] at the given location.
3176    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
3177        let offset = position.to_offset(self);
3178        let mut scope = None;
3179        let mut smallest_range_and_depth: Option<(Range<usize>, usize)> = None;
3180
3181        // Use the layer that has the smallest node intersecting the given point.
3182        for layer in self
3183            .syntax
3184            .layers_for_range(offset..offset, &self.text, false)
3185        {
3186            let mut cursor = layer.node().walk();
3187
3188            let mut range = None;
3189            loop {
3190                let child_range = cursor.node().byte_range();
3191                if !child_range.contains(&offset) {
3192                    break;
3193                }
3194
3195                range = Some(child_range);
3196                if cursor.goto_first_child_for_byte(offset).is_none() {
3197                    break;
3198                }
3199            }
3200
3201            if let Some(range) = range {
3202                if smallest_range_and_depth.as_ref().map_or(
3203                    true,
3204                    |(smallest_range, smallest_range_depth)| {
3205                        if layer.depth > *smallest_range_depth {
3206                            true
3207                        } else if layer.depth == *smallest_range_depth {
3208                            range.len() < smallest_range.len()
3209                        } else {
3210                            false
3211                        }
3212                    },
3213                ) {
3214                    smallest_range_and_depth = Some((range, layer.depth));
3215                    scope = Some(LanguageScope {
3216                        language: layer.language.clone(),
3217                        override_id: layer.override_id(offset, &self.text),
3218                    });
3219                }
3220            }
3221        }
3222
3223        scope.or_else(|| {
3224            self.language.clone().map(|language| LanguageScope {
3225                language,
3226                override_id: None,
3227            })
3228        })
3229    }
3230
3231    /// Returns a tuple of the range and character kind of the word
3232    /// surrounding the given position.
3233    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
3234        let mut start = start.to_offset(self);
3235        let mut end = start;
3236        let mut next_chars = self.chars_at(start).peekable();
3237        let mut prev_chars = self.reversed_chars_at(start).peekable();
3238
3239        let classifier = self.char_classifier_at(start);
3240        let word_kind = cmp::max(
3241            prev_chars.peek().copied().map(|c| classifier.kind(c)),
3242            next_chars.peek().copied().map(|c| classifier.kind(c)),
3243        );
3244
3245        for ch in prev_chars {
3246            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3247                start -= ch.len_utf8();
3248            } else {
3249                break;
3250            }
3251        }
3252
3253        for ch in next_chars {
3254            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3255                end += ch.len_utf8();
3256            } else {
3257                break;
3258            }
3259        }
3260
3261        (start..end, word_kind)
3262    }
3263
3264    /// Returns the closest syntax node enclosing the given range.
3265    pub fn syntax_ancestor<'a, T: ToOffset>(
3266        &'a self,
3267        range: Range<T>,
3268    ) -> Option<tree_sitter::Node<'a>> {
3269        let range = range.start.to_offset(self)..range.end.to_offset(self);
3270        let mut result: Option<tree_sitter::Node<'a>> = None;
3271        'outer: for layer in self
3272            .syntax
3273            .layers_for_range(range.clone(), &self.text, true)
3274        {
3275            let mut cursor = layer.node().walk();
3276
3277            // Descend to the first leaf that touches the start of the range,
3278            // and if the range is non-empty, extends beyond the start.
3279            while cursor.goto_first_child_for_byte(range.start).is_some() {
3280                if !range.is_empty() && cursor.node().end_byte() == range.start {
3281                    cursor.goto_next_sibling();
3282                }
3283            }
3284
3285            // Ascend to the smallest ancestor that strictly contains the range.
3286            loop {
3287                let node_range = cursor.node().byte_range();
3288                if node_range.start <= range.start
3289                    && node_range.end >= range.end
3290                    && node_range.len() > range.len()
3291                {
3292                    break;
3293                }
3294                if !cursor.goto_parent() {
3295                    continue 'outer;
3296                }
3297            }
3298
3299            let left_node = cursor.node();
3300            let mut layer_result = left_node;
3301
3302            // For an empty range, try to find another node immediately to the right of the range.
3303            if left_node.end_byte() == range.start {
3304                let mut right_node = None;
3305                while !cursor.goto_next_sibling() {
3306                    if !cursor.goto_parent() {
3307                        break;
3308                    }
3309                }
3310
3311                while cursor.node().start_byte() == range.start {
3312                    right_node = Some(cursor.node());
3313                    if !cursor.goto_first_child() {
3314                        break;
3315                    }
3316                }
3317
3318                // If there is a candidate node on both sides of the (empty) range, then
3319                // decide between the two by favoring a named node over an anonymous token.
3320                // If both nodes are the same in that regard, favor the right one.
3321                if let Some(right_node) = right_node {
3322                    if right_node.is_named() || !left_node.is_named() {
3323                        layer_result = right_node;
3324                    }
3325                }
3326            }
3327
3328            if let Some(previous_result) = &result {
3329                if previous_result.byte_range().len() < layer_result.byte_range().len() {
3330                    continue;
3331                }
3332            }
3333            result = Some(layer_result);
3334        }
3335
3336        result
3337    }
3338
3339    /// Returns the outline for the buffer.
3340    ///
3341    /// This method allows passing an optional [`SyntaxTheme`] to
3342    /// syntax-highlight the returned symbols.
3343    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
3344        self.outline_items_containing(0..self.len(), true, theme)
3345            .map(Outline::new)
3346    }
3347
3348    /// Returns all the symbols that contain the given position.
3349    ///
3350    /// This method allows passing an optional [`SyntaxTheme`] to
3351    /// syntax-highlight the returned symbols.
3352    pub fn symbols_containing<T: ToOffset>(
3353        &self,
3354        position: T,
3355        theme: Option<&SyntaxTheme>,
3356    ) -> Option<Vec<OutlineItem<Anchor>>> {
3357        let position = position.to_offset(self);
3358        let mut items = self.outline_items_containing(
3359            position.saturating_sub(1)..self.len().min(position + 1),
3360            false,
3361            theme,
3362        )?;
3363        let mut prev_depth = None;
3364        items.retain(|item| {
3365            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
3366            prev_depth = Some(item.depth);
3367            result
3368        });
3369        Some(items)
3370    }
3371
3372    pub fn outline_range_containing<T: ToOffset>(&self, range: Range<T>) -> Option<Range<Point>> {
3373        let range = range.to_offset(self);
3374        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3375            grammar.outline_config.as_ref().map(|c| &c.query)
3376        });
3377        let configs = matches
3378            .grammars()
3379            .iter()
3380            .map(|g| g.outline_config.as_ref().unwrap())
3381            .collect::<Vec<_>>();
3382
3383        while let Some(mat) = matches.peek() {
3384            let config = &configs[mat.grammar_index];
3385            let containing_item_node = maybe!({
3386                let item_node = mat.captures.iter().find_map(|cap| {
3387                    if cap.index == config.item_capture_ix {
3388                        Some(cap.node)
3389                    } else {
3390                        None
3391                    }
3392                })?;
3393
3394                let item_byte_range = item_node.byte_range();
3395                if item_byte_range.end < range.start || item_byte_range.start > range.end {
3396                    None
3397                } else {
3398                    Some(item_node)
3399                }
3400            });
3401
3402            if let Some(item_node) = containing_item_node {
3403                return Some(
3404                    Point::from_ts_point(item_node.start_position())
3405                        ..Point::from_ts_point(item_node.end_position()),
3406                );
3407            }
3408
3409            matches.advance();
3410        }
3411        None
3412    }
3413
3414    pub fn outline_items_containing<T: ToOffset>(
3415        &self,
3416        range: Range<T>,
3417        include_extra_context: bool,
3418        theme: Option<&SyntaxTheme>,
3419    ) -> Option<Vec<OutlineItem<Anchor>>> {
3420        let range = range.to_offset(self);
3421        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3422            grammar.outline_config.as_ref().map(|c| &c.query)
3423        });
3424        let configs = matches
3425            .grammars()
3426            .iter()
3427            .map(|g| g.outline_config.as_ref().unwrap())
3428            .collect::<Vec<_>>();
3429
3430        let mut items = Vec::new();
3431        let mut annotation_row_ranges: Vec<Range<u32>> = Vec::new();
3432        while let Some(mat) = matches.peek() {
3433            let config = &configs[mat.grammar_index];
3434            if let Some(item) =
3435                self.next_outline_item(config, &mat, &range, include_extra_context, theme)
3436            {
3437                items.push(item);
3438            } else if let Some(capture) = mat
3439                .captures
3440                .iter()
3441                .find(|capture| Some(capture.index) == config.annotation_capture_ix)
3442            {
3443                let capture_range = capture.node.start_position()..capture.node.end_position();
3444                let mut capture_row_range =
3445                    capture_range.start.row as u32..capture_range.end.row as u32;
3446                if capture_range.end.row > capture_range.start.row && capture_range.end.column == 0
3447                {
3448                    capture_row_range.end -= 1;
3449                }
3450                if let Some(last_row_range) = annotation_row_ranges.last_mut() {
3451                    if last_row_range.end >= capture_row_range.start.saturating_sub(1) {
3452                        last_row_range.end = capture_row_range.end;
3453                    } else {
3454                        annotation_row_ranges.push(capture_row_range);
3455                    }
3456                } else {
3457                    annotation_row_ranges.push(capture_row_range);
3458                }
3459            }
3460            matches.advance();
3461        }
3462
3463        items.sort_by_key(|item| (item.range.start, Reverse(item.range.end)));
3464
3465        // Assign depths based on containment relationships and convert to anchors.
3466        let mut item_ends_stack = Vec::<Point>::new();
3467        let mut anchor_items = Vec::new();
3468        let mut annotation_row_ranges = annotation_row_ranges.into_iter().peekable();
3469        for item in items {
3470            while let Some(last_end) = item_ends_stack.last().copied() {
3471                if last_end < item.range.end {
3472                    item_ends_stack.pop();
3473                } else {
3474                    break;
3475                }
3476            }
3477
3478            let mut annotation_row_range = None;
3479            while let Some(next_annotation_row_range) = annotation_row_ranges.peek() {
3480                let row_preceding_item = item.range.start.row.saturating_sub(1);
3481                if next_annotation_row_range.end < row_preceding_item {
3482                    annotation_row_ranges.next();
3483                } else {
3484                    if next_annotation_row_range.end == row_preceding_item {
3485                        annotation_row_range = Some(next_annotation_row_range.clone());
3486                        annotation_row_ranges.next();
3487                    }
3488                    break;
3489                }
3490            }
3491
3492            anchor_items.push(OutlineItem {
3493                depth: item_ends_stack.len(),
3494                range: self.anchor_after(item.range.start)..self.anchor_before(item.range.end),
3495                text: item.text,
3496                highlight_ranges: item.highlight_ranges,
3497                name_ranges: item.name_ranges,
3498                body_range: item.body_range.map(|body_range| {
3499                    self.anchor_after(body_range.start)..self.anchor_before(body_range.end)
3500                }),
3501                annotation_range: annotation_row_range.map(|annotation_range| {
3502                    self.anchor_after(Point::new(annotation_range.start, 0))
3503                        ..self.anchor_before(Point::new(
3504                            annotation_range.end,
3505                            self.line_len(annotation_range.end),
3506                        ))
3507                }),
3508            });
3509            item_ends_stack.push(item.range.end);
3510        }
3511
3512        Some(anchor_items)
3513    }
3514
3515    fn next_outline_item(
3516        &self,
3517        config: &OutlineConfig,
3518        mat: &SyntaxMapMatch,
3519        range: &Range<usize>,
3520        include_extra_context: bool,
3521        theme: Option<&SyntaxTheme>,
3522    ) -> Option<OutlineItem<Point>> {
3523        let item_node = mat.captures.iter().find_map(|cap| {
3524            if cap.index == config.item_capture_ix {
3525                Some(cap.node)
3526            } else {
3527                None
3528            }
3529        })?;
3530
3531        let item_byte_range = item_node.byte_range();
3532        if item_byte_range.end < range.start || item_byte_range.start > range.end {
3533            return None;
3534        }
3535        let item_point_range = Point::from_ts_point(item_node.start_position())
3536            ..Point::from_ts_point(item_node.end_position());
3537
3538        let mut open_point = None;
3539        let mut close_point = None;
3540        let mut buffer_ranges = Vec::new();
3541        for capture in mat.captures {
3542            let node_is_name;
3543            if capture.index == config.name_capture_ix {
3544                node_is_name = true;
3545            } else if Some(capture.index) == config.context_capture_ix
3546                || (Some(capture.index) == config.extra_context_capture_ix && include_extra_context)
3547            {
3548                node_is_name = false;
3549            } else {
3550                if Some(capture.index) == config.open_capture_ix {
3551                    open_point = Some(Point::from_ts_point(capture.node.end_position()));
3552                } else if Some(capture.index) == config.close_capture_ix {
3553                    close_point = Some(Point::from_ts_point(capture.node.start_position()));
3554                }
3555
3556                continue;
3557            }
3558
3559            let mut range = capture.node.start_byte()..capture.node.end_byte();
3560            let start = capture.node.start_position();
3561            if capture.node.end_position().row > start.row {
3562                range.end = range.start + self.line_len(start.row as u32) as usize - start.column;
3563            }
3564
3565            if !range.is_empty() {
3566                buffer_ranges.push((range, node_is_name));
3567            }
3568        }
3569        if buffer_ranges.is_empty() {
3570            return None;
3571        }
3572        let mut text = String::new();
3573        let mut highlight_ranges = Vec::new();
3574        let mut name_ranges = Vec::new();
3575        let mut chunks = self.chunks(
3576            buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
3577            true,
3578        );
3579        let mut last_buffer_range_end = 0;
3580
3581        for (buffer_range, is_name) in buffer_ranges {
3582            let space_added = !text.is_empty() && buffer_range.start > last_buffer_range_end;
3583            if space_added {
3584                text.push(' ');
3585            }
3586            let before_append_len = text.len();
3587            let mut offset = buffer_range.start;
3588            chunks.seek(buffer_range.clone());
3589            for mut chunk in chunks.by_ref() {
3590                if chunk.text.len() > buffer_range.end - offset {
3591                    chunk.text = &chunk.text[0..(buffer_range.end - offset)];
3592                    offset = buffer_range.end;
3593                } else {
3594                    offset += chunk.text.len();
3595                }
3596                let style = chunk
3597                    .syntax_highlight_id
3598                    .zip(theme)
3599                    .and_then(|(highlight, theme)| highlight.style(theme));
3600                if let Some(style) = style {
3601                    let start = text.len();
3602                    let end = start + chunk.text.len();
3603                    highlight_ranges.push((start..end, style));
3604                }
3605                text.push_str(chunk.text);
3606                if offset >= buffer_range.end {
3607                    break;
3608                }
3609            }
3610            if is_name {
3611                let after_append_len = text.len();
3612                let start = if space_added && !name_ranges.is_empty() {
3613                    before_append_len - 1
3614                } else {
3615                    before_append_len
3616                };
3617                name_ranges.push(start..after_append_len);
3618            }
3619            last_buffer_range_end = buffer_range.end;
3620        }
3621
3622        Some(OutlineItem {
3623            depth: 0, // We'll calculate the depth later
3624            range: item_point_range,
3625            text,
3626            highlight_ranges,
3627            name_ranges,
3628            body_range: open_point.zip(close_point).map(|(start, end)| start..end),
3629            annotation_range: None,
3630        })
3631    }
3632
3633    pub fn function_body_fold_ranges<T: ToOffset>(
3634        &self,
3635        within: Range<T>,
3636    ) -> impl Iterator<Item = Range<usize>> + '_ {
3637        self.text_object_ranges(within, TreeSitterOptions::default())
3638            .filter_map(|(range, obj)| (obj == TextObject::InsideFunction).then_some(range))
3639    }
3640
3641    /// For each grammar in the language, runs the provided
3642    /// [`tree_sitter::Query`] against the given range.
3643    pub fn matches(
3644        &self,
3645        range: Range<usize>,
3646        query: fn(&Grammar) -> Option<&tree_sitter::Query>,
3647    ) -> SyntaxMapMatches {
3648        self.syntax.matches(range, self, query)
3649    }
3650
3651    pub fn all_bracket_ranges(
3652        &self,
3653        range: Range<usize>,
3654    ) -> impl Iterator<Item = BracketMatch> + '_ {
3655        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3656            grammar.brackets_config.as_ref().map(|c| &c.query)
3657        });
3658        let configs = matches
3659            .grammars()
3660            .iter()
3661            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
3662            .collect::<Vec<_>>();
3663
3664        iter::from_fn(move || {
3665            while let Some(mat) = matches.peek() {
3666                let mut open = None;
3667                let mut close = None;
3668                let config = &configs[mat.grammar_index];
3669                let pattern = &config.patterns[mat.pattern_index];
3670                for capture in mat.captures {
3671                    if capture.index == config.open_capture_ix {
3672                        open = Some(capture.node.byte_range());
3673                    } else if capture.index == config.close_capture_ix {
3674                        close = Some(capture.node.byte_range());
3675                    }
3676                }
3677
3678                matches.advance();
3679
3680                let Some((open_range, close_range)) = open.zip(close) else {
3681                    continue;
3682                };
3683
3684                let bracket_range = open_range.start..=close_range.end;
3685                if !bracket_range.overlaps(&range) {
3686                    continue;
3687                }
3688
3689                return Some(BracketMatch {
3690                    open_range,
3691                    close_range,
3692                    newline_only: pattern.newline_only,
3693                });
3694            }
3695            None
3696        })
3697    }
3698
3699    /// Returns bracket range pairs overlapping or adjacent to `range`
3700    pub fn bracket_ranges<T: ToOffset>(
3701        &self,
3702        range: Range<T>,
3703    ) -> impl Iterator<Item = BracketMatch> + '_ {
3704        // Find bracket pairs that *inclusively* contain the given range.
3705        let range = range.start.to_offset(self).saturating_sub(1)
3706            ..self.len().min(range.end.to_offset(self) + 1);
3707        self.all_bracket_ranges(range)
3708            .filter(|pair| !pair.newline_only)
3709    }
3710
3711    pub fn text_object_ranges<T: ToOffset>(
3712        &self,
3713        range: Range<T>,
3714        options: TreeSitterOptions,
3715    ) -> impl Iterator<Item = (Range<usize>, TextObject)> + '_ {
3716        let range = range.start.to_offset(self).saturating_sub(1)
3717            ..self.len().min(range.end.to_offset(self) + 1);
3718
3719        let mut matches =
3720            self.syntax
3721                .matches_with_options(range.clone(), &self.text, options, |grammar| {
3722                    grammar.text_object_config.as_ref().map(|c| &c.query)
3723                });
3724
3725        let configs = matches
3726            .grammars()
3727            .iter()
3728            .map(|grammar| grammar.text_object_config.as_ref())
3729            .collect::<Vec<_>>();
3730
3731        let mut captures = Vec::<(Range<usize>, TextObject)>::new();
3732
3733        iter::from_fn(move || {
3734            loop {
3735                while let Some(capture) = captures.pop() {
3736                    if capture.0.overlaps(&range) {
3737                        return Some(capture);
3738                    }
3739                }
3740
3741                let mat = matches.peek()?;
3742
3743                let Some(config) = configs[mat.grammar_index].as_ref() else {
3744                    matches.advance();
3745                    continue;
3746                };
3747
3748                for capture in mat.captures {
3749                    let Some(ix) = config
3750                        .text_objects_by_capture_ix
3751                        .binary_search_by_key(&capture.index, |e| e.0)
3752                        .ok()
3753                    else {
3754                        continue;
3755                    };
3756                    let text_object = config.text_objects_by_capture_ix[ix].1;
3757                    let byte_range = capture.node.byte_range();
3758
3759                    let mut found = false;
3760                    for (range, existing) in captures.iter_mut() {
3761                        if existing == &text_object {
3762                            range.start = range.start.min(byte_range.start);
3763                            range.end = range.end.max(byte_range.end);
3764                            found = true;
3765                            break;
3766                        }
3767                    }
3768
3769                    if !found {
3770                        captures.push((byte_range, text_object));
3771                    }
3772                }
3773
3774                matches.advance();
3775            }
3776        })
3777    }
3778
3779    /// Returns enclosing bracket ranges containing the given range
3780    pub fn enclosing_bracket_ranges<T: ToOffset>(
3781        &self,
3782        range: Range<T>,
3783    ) -> impl Iterator<Item = BracketMatch> + '_ {
3784        let range = range.start.to_offset(self)..range.end.to_offset(self);
3785
3786        self.bracket_ranges(range.clone()).filter(move |pair| {
3787            pair.open_range.start <= range.start && pair.close_range.end >= range.end
3788        })
3789    }
3790
3791    /// Returns the smallest enclosing bracket ranges containing the given range or None if no brackets contain range
3792    ///
3793    /// Can optionally pass a range_filter to filter the ranges of brackets to consider
3794    pub fn innermost_enclosing_bracket_ranges<T: ToOffset>(
3795        &self,
3796        range: Range<T>,
3797        range_filter: Option<&dyn Fn(Range<usize>, Range<usize>) -> bool>,
3798    ) -> Option<(Range<usize>, Range<usize>)> {
3799        let range = range.start.to_offset(self)..range.end.to_offset(self);
3800
3801        // Get the ranges of the innermost pair of brackets.
3802        let mut result: Option<(Range<usize>, Range<usize>)> = None;
3803
3804        for pair in self.enclosing_bracket_ranges(range.clone()) {
3805            if let Some(range_filter) = range_filter {
3806                if !range_filter(pair.open_range.clone(), pair.close_range.clone()) {
3807                    continue;
3808                }
3809            }
3810
3811            let len = pair.close_range.end - pair.open_range.start;
3812
3813            if let Some((existing_open, existing_close)) = &result {
3814                let existing_len = existing_close.end - existing_open.start;
3815                if len > existing_len {
3816                    continue;
3817                }
3818            }
3819
3820            result = Some((pair.open_range, pair.close_range));
3821        }
3822
3823        result
3824    }
3825
3826    /// Returns anchor ranges for any matches of the redaction query.
3827    /// The buffer can be associated with multiple languages, and the redaction query associated with each
3828    /// will be run on the relevant section of the buffer.
3829    pub fn redacted_ranges<T: ToOffset>(
3830        &self,
3831        range: Range<T>,
3832    ) -> impl Iterator<Item = Range<usize>> + '_ {
3833        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3834        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3835            grammar
3836                .redactions_config
3837                .as_ref()
3838                .map(|config| &config.query)
3839        });
3840
3841        let configs = syntax_matches
3842            .grammars()
3843            .iter()
3844            .map(|grammar| grammar.redactions_config.as_ref())
3845            .collect::<Vec<_>>();
3846
3847        iter::from_fn(move || {
3848            let redacted_range = syntax_matches
3849                .peek()
3850                .and_then(|mat| {
3851                    configs[mat.grammar_index].and_then(|config| {
3852                        mat.captures
3853                            .iter()
3854                            .find(|capture| capture.index == config.redaction_capture_ix)
3855                    })
3856                })
3857                .map(|mat| mat.node.byte_range());
3858            syntax_matches.advance();
3859            redacted_range
3860        })
3861    }
3862
3863    pub fn injections_intersecting_range<T: ToOffset>(
3864        &self,
3865        range: Range<T>,
3866    ) -> impl Iterator<Item = (Range<usize>, &Arc<Language>)> + '_ {
3867        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3868
3869        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3870            grammar
3871                .injection_config
3872                .as_ref()
3873                .map(|config| &config.query)
3874        });
3875
3876        let configs = syntax_matches
3877            .grammars()
3878            .iter()
3879            .map(|grammar| grammar.injection_config.as_ref())
3880            .collect::<Vec<_>>();
3881
3882        iter::from_fn(move || {
3883            let ranges = syntax_matches.peek().and_then(|mat| {
3884                let config = &configs[mat.grammar_index]?;
3885                let content_capture_range = mat.captures.iter().find_map(|capture| {
3886                    if capture.index == config.content_capture_ix {
3887                        Some(capture.node.byte_range())
3888                    } else {
3889                        None
3890                    }
3891                })?;
3892                let language = self.language_at(content_capture_range.start)?;
3893                Some((content_capture_range, language))
3894            });
3895            syntax_matches.advance();
3896            ranges
3897        })
3898    }
3899
3900    pub fn debug_variable_ranges(
3901        &self,
3902        offset_range: Range<usize>,
3903    ) -> impl Iterator<Item = DebugVariableRanges> + '_ {
3904        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3905            grammar
3906                .debug_variables_config
3907                .as_ref()
3908                .map(|config| &config.query)
3909        });
3910
3911        let configs = syntax_matches
3912            .grammars()
3913            .iter()
3914            .map(|grammar| grammar.debug_variables_config.as_ref())
3915            .collect::<Vec<_>>();
3916
3917        iter::from_fn(move || {
3918            loop {
3919                let mat = syntax_matches.peek()?;
3920
3921                let variable_ranges = configs[mat.grammar_index].and_then(|config| {
3922                    let full_range = mat.captures.iter().fold(
3923                        Range {
3924                            start: usize::MAX,
3925                            end: 0,
3926                        },
3927                        |mut acc, next| {
3928                            let byte_range = next.node.byte_range();
3929                            if acc.start > byte_range.start {
3930                                acc.start = byte_range.start;
3931                            }
3932                            if acc.end < byte_range.end {
3933                                acc.end = byte_range.end;
3934                            }
3935                            acc
3936                        },
3937                    );
3938                    if full_range.start > full_range.end {
3939                        // We did not find a full spanning range of this match.
3940                        return None;
3941                    }
3942
3943                    let captures = mat.captures.iter().filter_map(|capture| {
3944                        Some((
3945                            capture,
3946                            config.captures.get(capture.index as usize).cloned()?,
3947                        ))
3948                    });
3949
3950                    let mut variable_range = None;
3951                    for (query, capture) in captures {
3952                        if let DebugVariableCapture::Variable = capture {
3953                            let _ = variable_range.insert(query.node.byte_range());
3954                        }
3955                    }
3956
3957                    Some(DebugVariableRanges {
3958                        buffer_id: self.remote_id(),
3959                        range: variable_range?,
3960                    })
3961                });
3962
3963                syntax_matches.advance();
3964                if variable_ranges.is_some() {
3965                    // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
3966                    // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
3967                    return variable_ranges;
3968                }
3969            }
3970        })
3971    }
3972
3973    pub fn runnable_ranges(
3974        &self,
3975        offset_range: Range<usize>,
3976    ) -> impl Iterator<Item = RunnableRange> + '_ {
3977        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3978            grammar.runnable_config.as_ref().map(|config| &config.query)
3979        });
3980
3981        let test_configs = syntax_matches
3982            .grammars()
3983            .iter()
3984            .map(|grammar| grammar.runnable_config.as_ref())
3985            .collect::<Vec<_>>();
3986
3987        iter::from_fn(move || {
3988            loop {
3989                let mat = syntax_matches.peek()?;
3990
3991                let test_range = test_configs[mat.grammar_index].and_then(|test_configs| {
3992                    let mut run_range = None;
3993                    let full_range = mat.captures.iter().fold(
3994                        Range {
3995                            start: usize::MAX,
3996                            end: 0,
3997                        },
3998                        |mut acc, next| {
3999                            let byte_range = next.node.byte_range();
4000                            if acc.start > byte_range.start {
4001                                acc.start = byte_range.start;
4002                            }
4003                            if acc.end < byte_range.end {
4004                                acc.end = byte_range.end;
4005                            }
4006                            acc
4007                        },
4008                    );
4009                    if full_range.start > full_range.end {
4010                        // We did not find a full spanning range of this match.
4011                        return None;
4012                    }
4013                    let extra_captures: SmallVec<[_; 1]> =
4014                        SmallVec::from_iter(mat.captures.iter().filter_map(|capture| {
4015                            test_configs
4016                                .extra_captures
4017                                .get(capture.index as usize)
4018                                .cloned()
4019                                .and_then(|tag_name| match tag_name {
4020                                    RunnableCapture::Named(name) => {
4021                                        Some((capture.node.byte_range(), name))
4022                                    }
4023                                    RunnableCapture::Run => {
4024                                        let _ = run_range.insert(capture.node.byte_range());
4025                                        None
4026                                    }
4027                                })
4028                        }));
4029                    let run_range = run_range?;
4030                    let tags = test_configs
4031                        .query
4032                        .property_settings(mat.pattern_index)
4033                        .iter()
4034                        .filter_map(|property| {
4035                            if *property.key == *"tag" {
4036                                property
4037                                    .value
4038                                    .as_ref()
4039                                    .map(|value| RunnableTag(value.to_string().into()))
4040                            } else {
4041                                None
4042                            }
4043                        })
4044                        .collect();
4045                    let extra_captures = extra_captures
4046                        .into_iter()
4047                        .map(|(range, name)| {
4048                            (
4049                                name.to_string(),
4050                                self.text_for_range(range.clone()).collect::<String>(),
4051                            )
4052                        })
4053                        .collect();
4054                    // All tags should have the same range.
4055                    Some(RunnableRange {
4056                        run_range,
4057                        full_range,
4058                        runnable: Runnable {
4059                            tags,
4060                            language: mat.language,
4061                            buffer: self.remote_id(),
4062                        },
4063                        extra_captures,
4064                        buffer_id: self.remote_id(),
4065                    })
4066                });
4067
4068                syntax_matches.advance();
4069                if test_range.is_some() {
4070                    // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
4071                    // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
4072                    return test_range;
4073                }
4074            }
4075        })
4076    }
4077
4078    /// Returns selections for remote peers intersecting the given range.
4079    #[allow(clippy::type_complexity)]
4080    pub fn selections_in_range(
4081        &self,
4082        range: Range<Anchor>,
4083        include_local: bool,
4084    ) -> impl Iterator<
4085        Item = (
4086            ReplicaId,
4087            bool,
4088            CursorShape,
4089            impl Iterator<Item = &Selection<Anchor>> + '_,
4090        ),
4091    > + '_ {
4092        self.remote_selections
4093            .iter()
4094            .filter(move |(replica_id, set)| {
4095                (include_local || **replica_id != self.text.replica_id())
4096                    && !set.selections.is_empty()
4097            })
4098            .map(move |(replica_id, set)| {
4099                let start_ix = match set.selections.binary_search_by(|probe| {
4100                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
4101                }) {
4102                    Ok(ix) | Err(ix) => ix,
4103                };
4104                let end_ix = match set.selections.binary_search_by(|probe| {
4105                    probe.start.cmp(&range.end, self).then(Ordering::Less)
4106                }) {
4107                    Ok(ix) | Err(ix) => ix,
4108                };
4109
4110                (
4111                    *replica_id,
4112                    set.line_mode,
4113                    set.cursor_shape,
4114                    set.selections[start_ix..end_ix].iter(),
4115                )
4116            })
4117    }
4118
4119    /// Returns if the buffer contains any diagnostics.
4120    pub fn has_diagnostics(&self) -> bool {
4121        !self.diagnostics.is_empty()
4122    }
4123
4124    /// Returns all the diagnostics intersecting the given range.
4125    pub fn diagnostics_in_range<'a, T, O>(
4126        &'a self,
4127        search_range: Range<T>,
4128        reversed: bool,
4129    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
4130    where
4131        T: 'a + Clone + ToOffset,
4132        O: 'a + FromAnchor,
4133    {
4134        let mut iterators: Vec<_> = self
4135            .diagnostics
4136            .iter()
4137            .map(|(_, collection)| {
4138                collection
4139                    .range::<T, text::Anchor>(search_range.clone(), self, true, reversed)
4140                    .peekable()
4141            })
4142            .collect();
4143
4144        std::iter::from_fn(move || {
4145            let (next_ix, _) = iterators
4146                .iter_mut()
4147                .enumerate()
4148                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
4149                .min_by(|(_, a), (_, b)| {
4150                    let cmp = a
4151                        .range
4152                        .start
4153                        .cmp(&b.range.start, self)
4154                        // when range is equal, sort by diagnostic severity
4155                        .then(a.diagnostic.severity.cmp(&b.diagnostic.severity))
4156                        // and stabilize order with group_id
4157                        .then(a.diagnostic.group_id.cmp(&b.diagnostic.group_id));
4158                    if reversed { cmp.reverse() } else { cmp }
4159                })?;
4160            iterators[next_ix]
4161                .next()
4162                .map(|DiagnosticEntry { range, diagnostic }| DiagnosticEntry {
4163                    diagnostic,
4164                    range: FromAnchor::from_anchor(&range.start, self)
4165                        ..FromAnchor::from_anchor(&range.end, self),
4166                })
4167        })
4168    }
4169
4170    /// Returns all the diagnostic groups associated with the given
4171    /// language server ID. If no language server ID is provided,
4172    /// all diagnostics groups are returned.
4173    pub fn diagnostic_groups(
4174        &self,
4175        language_server_id: Option<LanguageServerId>,
4176    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
4177        let mut groups = Vec::new();
4178
4179        if let Some(language_server_id) = language_server_id {
4180            if let Ok(ix) = self
4181                .diagnostics
4182                .binary_search_by_key(&language_server_id, |e| e.0)
4183            {
4184                self.diagnostics[ix]
4185                    .1
4186                    .groups(language_server_id, &mut groups, self);
4187            }
4188        } else {
4189            for (language_server_id, diagnostics) in self.diagnostics.iter() {
4190                diagnostics.groups(*language_server_id, &mut groups, self);
4191            }
4192        }
4193
4194        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
4195            let a_start = &group_a.entries[group_a.primary_ix].range.start;
4196            let b_start = &group_b.entries[group_b.primary_ix].range.start;
4197            a_start.cmp(b_start, self).then_with(|| id_a.cmp(id_b))
4198        });
4199
4200        groups
4201    }
4202
4203    /// Returns an iterator over the diagnostics for the given group.
4204    pub fn diagnostic_group<O>(
4205        &self,
4206        group_id: usize,
4207    ) -> impl Iterator<Item = DiagnosticEntry<O>> + '_
4208    where
4209        O: FromAnchor + 'static,
4210    {
4211        self.diagnostics
4212            .iter()
4213            .flat_map(move |(_, set)| set.group(group_id, self))
4214    }
4215
4216    /// An integer version number that accounts for all updates besides
4217    /// the buffer's text itself (which is versioned via a version vector).
4218    pub fn non_text_state_update_count(&self) -> usize {
4219        self.non_text_state_update_count
4220    }
4221
4222    /// Returns a snapshot of underlying file.
4223    pub fn file(&self) -> Option<&Arc<dyn File>> {
4224        self.file.as_ref()
4225    }
4226
4227    /// Resolves the file path (relative to the worktree root) associated with the underlying file.
4228    pub fn resolve_file_path(&self, cx: &App, include_root: bool) -> Option<PathBuf> {
4229        if let Some(file) = self.file() {
4230            if file.path().file_name().is_none() || include_root {
4231                Some(file.full_path(cx))
4232            } else {
4233                Some(file.path().to_path_buf())
4234            }
4235        } else {
4236            None
4237        }
4238    }
4239
4240    pub fn words_in_range(&self, query: WordsQuery) -> BTreeMap<String, Range<Anchor>> {
4241        let query_str = query.fuzzy_contents;
4242        if query_str.map_or(false, |query| query.is_empty()) {
4243            return BTreeMap::default();
4244        }
4245
4246        let classifier = CharClassifier::new(self.language.clone().map(|language| LanguageScope {
4247            language,
4248            override_id: None,
4249        }));
4250
4251        let mut query_ix = 0;
4252        let query_chars = query_str.map(|query| query.chars().collect::<Vec<_>>());
4253        let query_len = query_chars.as_ref().map_or(0, |query| query.len());
4254
4255        let mut words = BTreeMap::default();
4256        let mut current_word_start_ix = None;
4257        let mut chunk_ix = query.range.start;
4258        for chunk in self.chunks(query.range, false) {
4259            for (i, c) in chunk.text.char_indices() {
4260                let ix = chunk_ix + i;
4261                if classifier.is_word(c) {
4262                    if current_word_start_ix.is_none() {
4263                        current_word_start_ix = Some(ix);
4264                    }
4265
4266                    if let Some(query_chars) = &query_chars {
4267                        if query_ix < query_len {
4268                            if c.to_lowercase().eq(query_chars[query_ix].to_lowercase()) {
4269                                query_ix += 1;
4270                            }
4271                        }
4272                    }
4273                    continue;
4274                } else if let Some(word_start) = current_word_start_ix.take() {
4275                    if query_ix == query_len {
4276                        let word_range = self.anchor_before(word_start)..self.anchor_after(ix);
4277                        let mut word_text = self.text_for_range(word_start..ix).peekable();
4278                        let first_char = word_text
4279                            .peek()
4280                            .and_then(|first_chunk| first_chunk.chars().next());
4281                        // Skip empty and "words" starting with digits as a heuristic to reduce useless completions
4282                        if !query.skip_digits
4283                            || first_char.map_or(true, |first_char| !first_char.is_digit(10))
4284                        {
4285                            words.insert(word_text.collect(), word_range);
4286                        }
4287                    }
4288                }
4289                query_ix = 0;
4290            }
4291            chunk_ix += chunk.text.len();
4292        }
4293
4294        words
4295    }
4296}
4297
4298pub struct WordsQuery<'a> {
4299    /// Only returns words with all chars from the fuzzy string in them.
4300    pub fuzzy_contents: Option<&'a str>,
4301    /// Skips words that start with a digit.
4302    pub skip_digits: bool,
4303    /// Buffer offset range, to look for words.
4304    pub range: Range<usize>,
4305}
4306
4307fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
4308    indent_size_for_text(text.chars_at(Point::new(row, 0)))
4309}
4310
4311fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
4312    let mut result = IndentSize::spaces(0);
4313    for c in text {
4314        let kind = match c {
4315            ' ' => IndentKind::Space,
4316            '\t' => IndentKind::Tab,
4317            _ => break,
4318        };
4319        if result.len == 0 {
4320            result.kind = kind;
4321        }
4322        result.len += 1;
4323    }
4324    result
4325}
4326
4327impl Clone for BufferSnapshot {
4328    fn clone(&self) -> Self {
4329        Self {
4330            text: self.text.clone(),
4331            syntax: self.syntax.clone(),
4332            file: self.file.clone(),
4333            remote_selections: self.remote_selections.clone(),
4334            diagnostics: self.diagnostics.clone(),
4335            language: self.language.clone(),
4336            non_text_state_update_count: self.non_text_state_update_count,
4337        }
4338    }
4339}
4340
4341impl Deref for BufferSnapshot {
4342    type Target = text::BufferSnapshot;
4343
4344    fn deref(&self) -> &Self::Target {
4345        &self.text
4346    }
4347}
4348
4349unsafe impl Send for BufferChunks<'_> {}
4350
4351impl<'a> BufferChunks<'a> {
4352    pub(crate) fn new(
4353        text: &'a Rope,
4354        range: Range<usize>,
4355        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
4356        diagnostics: bool,
4357        buffer_snapshot: Option<&'a BufferSnapshot>,
4358    ) -> Self {
4359        let mut highlights = None;
4360        if let Some((captures, highlight_maps)) = syntax {
4361            highlights = Some(BufferChunkHighlights {
4362                captures,
4363                next_capture: None,
4364                stack: Default::default(),
4365                highlight_maps,
4366            })
4367        }
4368
4369        let diagnostic_endpoints = diagnostics.then(|| Vec::new().into_iter().peekable());
4370        let chunks = text.chunks_in_range(range.clone());
4371
4372        let mut this = BufferChunks {
4373            range,
4374            buffer_snapshot,
4375            chunks,
4376            diagnostic_endpoints,
4377            error_depth: 0,
4378            warning_depth: 0,
4379            information_depth: 0,
4380            hint_depth: 0,
4381            unnecessary_depth: 0,
4382            highlights,
4383        };
4384        this.initialize_diagnostic_endpoints();
4385        this
4386    }
4387
4388    /// Seeks to the given byte offset in the buffer.
4389    pub fn seek(&mut self, range: Range<usize>) {
4390        let old_range = std::mem::replace(&mut self.range, range.clone());
4391        self.chunks.set_range(self.range.clone());
4392        if let Some(highlights) = self.highlights.as_mut() {
4393            if old_range.start <= self.range.start && old_range.end >= self.range.end {
4394                // Reuse existing highlights stack, as the new range is a subrange of the old one.
4395                highlights
4396                    .stack
4397                    .retain(|(end_offset, _)| *end_offset > range.start);
4398                if let Some(capture) = &highlights.next_capture {
4399                    if range.start >= capture.node.start_byte() {
4400                        let next_capture_end = capture.node.end_byte();
4401                        if range.start < next_capture_end {
4402                            highlights.stack.push((
4403                                next_capture_end,
4404                                highlights.highlight_maps[capture.grammar_index].get(capture.index),
4405                            ));
4406                        }
4407                        highlights.next_capture.take();
4408                    }
4409                }
4410            } else if let Some(snapshot) = self.buffer_snapshot {
4411                let (captures, highlight_maps) = snapshot.get_highlights(self.range.clone());
4412                *highlights = BufferChunkHighlights {
4413                    captures,
4414                    next_capture: None,
4415                    stack: Default::default(),
4416                    highlight_maps,
4417                };
4418            } else {
4419                // We cannot obtain new highlights for a language-aware buffer iterator, as we don't have a buffer snapshot.
4420                // Seeking such BufferChunks is not supported.
4421                debug_assert!(
4422                    false,
4423                    "Attempted to seek on a language-aware buffer iterator without associated buffer snapshot"
4424                );
4425            }
4426
4427            highlights.captures.set_byte_range(self.range.clone());
4428            self.initialize_diagnostic_endpoints();
4429        }
4430    }
4431
4432    fn initialize_diagnostic_endpoints(&mut self) {
4433        if let Some(diagnostics) = self.diagnostic_endpoints.as_mut() {
4434            if let Some(buffer) = self.buffer_snapshot {
4435                let mut diagnostic_endpoints = Vec::new();
4436                for entry in buffer.diagnostics_in_range::<_, usize>(self.range.clone(), false) {
4437                    diagnostic_endpoints.push(DiagnosticEndpoint {
4438                        offset: entry.range.start,
4439                        is_start: true,
4440                        severity: entry.diagnostic.severity,
4441                        is_unnecessary: entry.diagnostic.is_unnecessary,
4442                    });
4443                    diagnostic_endpoints.push(DiagnosticEndpoint {
4444                        offset: entry.range.end,
4445                        is_start: false,
4446                        severity: entry.diagnostic.severity,
4447                        is_unnecessary: entry.diagnostic.is_unnecessary,
4448                    });
4449                }
4450                diagnostic_endpoints
4451                    .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
4452                *diagnostics = diagnostic_endpoints.into_iter().peekable();
4453                self.hint_depth = 0;
4454                self.error_depth = 0;
4455                self.warning_depth = 0;
4456                self.information_depth = 0;
4457            }
4458        }
4459    }
4460
4461    /// The current byte offset in the buffer.
4462    pub fn offset(&self) -> usize {
4463        self.range.start
4464    }
4465
4466    pub fn range(&self) -> Range<usize> {
4467        self.range.clone()
4468    }
4469
4470    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
4471        let depth = match endpoint.severity {
4472            DiagnosticSeverity::ERROR => &mut self.error_depth,
4473            DiagnosticSeverity::WARNING => &mut self.warning_depth,
4474            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
4475            DiagnosticSeverity::HINT => &mut self.hint_depth,
4476            _ => return,
4477        };
4478        if endpoint.is_start {
4479            *depth += 1;
4480        } else {
4481            *depth -= 1;
4482        }
4483
4484        if endpoint.is_unnecessary {
4485            if endpoint.is_start {
4486                self.unnecessary_depth += 1;
4487            } else {
4488                self.unnecessary_depth -= 1;
4489            }
4490        }
4491    }
4492
4493    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
4494        if self.error_depth > 0 {
4495            Some(DiagnosticSeverity::ERROR)
4496        } else if self.warning_depth > 0 {
4497            Some(DiagnosticSeverity::WARNING)
4498        } else if self.information_depth > 0 {
4499            Some(DiagnosticSeverity::INFORMATION)
4500        } else if self.hint_depth > 0 {
4501            Some(DiagnosticSeverity::HINT)
4502        } else {
4503            None
4504        }
4505    }
4506
4507    fn current_code_is_unnecessary(&self) -> bool {
4508        self.unnecessary_depth > 0
4509    }
4510}
4511
4512impl<'a> Iterator for BufferChunks<'a> {
4513    type Item = Chunk<'a>;
4514
4515    fn next(&mut self) -> Option<Self::Item> {
4516        let mut next_capture_start = usize::MAX;
4517        let mut next_diagnostic_endpoint = usize::MAX;
4518
4519        if let Some(highlights) = self.highlights.as_mut() {
4520            while let Some((parent_capture_end, _)) = highlights.stack.last() {
4521                if *parent_capture_end <= self.range.start {
4522                    highlights.stack.pop();
4523                } else {
4524                    break;
4525                }
4526            }
4527
4528            if highlights.next_capture.is_none() {
4529                highlights.next_capture = highlights.captures.next();
4530            }
4531
4532            while let Some(capture) = highlights.next_capture.as_ref() {
4533                if self.range.start < capture.node.start_byte() {
4534                    next_capture_start = capture.node.start_byte();
4535                    break;
4536                } else {
4537                    let highlight_id =
4538                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
4539                    highlights
4540                        .stack
4541                        .push((capture.node.end_byte(), highlight_id));
4542                    highlights.next_capture = highlights.captures.next();
4543                }
4544            }
4545        }
4546
4547        let mut diagnostic_endpoints = std::mem::take(&mut self.diagnostic_endpoints);
4548        if let Some(diagnostic_endpoints) = diagnostic_endpoints.as_mut() {
4549            while let Some(endpoint) = diagnostic_endpoints.peek().copied() {
4550                if endpoint.offset <= self.range.start {
4551                    self.update_diagnostic_depths(endpoint);
4552                    diagnostic_endpoints.next();
4553                } else {
4554                    next_diagnostic_endpoint = endpoint.offset;
4555                    break;
4556                }
4557            }
4558        }
4559        self.diagnostic_endpoints = diagnostic_endpoints;
4560
4561        if let Some(chunk) = self.chunks.peek() {
4562            let chunk_start = self.range.start;
4563            let mut chunk_end = (self.chunks.offset() + chunk.len())
4564                .min(next_capture_start)
4565                .min(next_diagnostic_endpoint);
4566            let mut highlight_id = None;
4567            if let Some(highlights) = self.highlights.as_ref() {
4568                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
4569                    chunk_end = chunk_end.min(*parent_capture_end);
4570                    highlight_id = Some(*parent_highlight_id);
4571                }
4572            }
4573
4574            let slice =
4575                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
4576            self.range.start = chunk_end;
4577            if self.range.start == self.chunks.offset() + chunk.len() {
4578                self.chunks.next().unwrap();
4579            }
4580
4581            Some(Chunk {
4582                text: slice,
4583                syntax_highlight_id: highlight_id,
4584                diagnostic_severity: self.current_diagnostic_severity(),
4585                is_unnecessary: self.current_code_is_unnecessary(),
4586                ..Default::default()
4587            })
4588        } else {
4589            None
4590        }
4591    }
4592}
4593
4594impl operation_queue::Operation for Operation {
4595    fn lamport_timestamp(&self) -> clock::Lamport {
4596        match self {
4597            Operation::Buffer(_) => {
4598                unreachable!("buffer operations should never be deferred at this layer")
4599            }
4600            Operation::UpdateDiagnostics {
4601                lamport_timestamp, ..
4602            }
4603            | Operation::UpdateSelections {
4604                lamport_timestamp, ..
4605            }
4606            | Operation::UpdateCompletionTriggers {
4607                lamport_timestamp, ..
4608            } => *lamport_timestamp,
4609        }
4610    }
4611}
4612
4613impl Default for Diagnostic {
4614    fn default() -> Self {
4615        Self {
4616            source: Default::default(),
4617            code: None,
4618            code_description: None,
4619            severity: DiagnosticSeverity::ERROR,
4620            message: Default::default(),
4621            markdown: None,
4622            group_id: 0,
4623            is_primary: false,
4624            is_disk_based: false,
4625            is_unnecessary: false,
4626            data: None,
4627        }
4628    }
4629}
4630
4631impl IndentSize {
4632    /// Returns an [`IndentSize`] representing the given spaces.
4633    pub fn spaces(len: u32) -> Self {
4634        Self {
4635            len,
4636            kind: IndentKind::Space,
4637        }
4638    }
4639
4640    /// Returns an [`IndentSize`] representing a tab.
4641    pub fn tab() -> Self {
4642        Self {
4643            len: 1,
4644            kind: IndentKind::Tab,
4645        }
4646    }
4647
4648    /// An iterator over the characters represented by this [`IndentSize`].
4649    pub fn chars(&self) -> impl Iterator<Item = char> {
4650        iter::repeat(self.char()).take(self.len as usize)
4651    }
4652
4653    /// The character representation of this [`IndentSize`].
4654    pub fn char(&self) -> char {
4655        match self.kind {
4656            IndentKind::Space => ' ',
4657            IndentKind::Tab => '\t',
4658        }
4659    }
4660
4661    /// Consumes the current [`IndentSize`] and returns a new one that has
4662    /// been shrunk or enlarged by the given size along the given direction.
4663    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
4664        match direction {
4665            Ordering::Less => {
4666                if self.kind == size.kind && self.len >= size.len {
4667                    self.len -= size.len;
4668                }
4669            }
4670            Ordering::Equal => {}
4671            Ordering::Greater => {
4672                if self.len == 0 {
4673                    self = size;
4674                } else if self.kind == size.kind {
4675                    self.len += size.len;
4676                }
4677            }
4678        }
4679        self
4680    }
4681
4682    pub fn len_with_expanded_tabs(&self, tab_size: NonZeroU32) -> usize {
4683        match self.kind {
4684            IndentKind::Space => self.len as usize,
4685            IndentKind::Tab => self.len as usize * tab_size.get() as usize,
4686        }
4687    }
4688}
4689
4690#[cfg(any(test, feature = "test-support"))]
4691pub struct TestFile {
4692    pub path: Arc<Path>,
4693    pub root_name: String,
4694    pub local_root: Option<PathBuf>,
4695}
4696
4697#[cfg(any(test, feature = "test-support"))]
4698impl File for TestFile {
4699    fn path(&self) -> &Arc<Path> {
4700        &self.path
4701    }
4702
4703    fn full_path(&self, _: &gpui::App) -> PathBuf {
4704        PathBuf::from(&self.root_name).join(self.path.as_ref())
4705    }
4706
4707    fn as_local(&self) -> Option<&dyn LocalFile> {
4708        if self.local_root.is_some() {
4709            Some(self)
4710        } else {
4711            None
4712        }
4713    }
4714
4715    fn disk_state(&self) -> DiskState {
4716        unimplemented!()
4717    }
4718
4719    fn file_name<'a>(&'a self, _: &'a gpui::App) -> &'a std::ffi::OsStr {
4720        self.path().file_name().unwrap_or(self.root_name.as_ref())
4721    }
4722
4723    fn worktree_id(&self, _: &App) -> WorktreeId {
4724        WorktreeId::from_usize(0)
4725    }
4726
4727    fn to_proto(&self, _: &App) -> rpc::proto::File {
4728        unimplemented!()
4729    }
4730
4731    fn is_private(&self) -> bool {
4732        false
4733    }
4734}
4735
4736#[cfg(any(test, feature = "test-support"))]
4737impl LocalFile for TestFile {
4738    fn abs_path(&self, _cx: &App) -> PathBuf {
4739        PathBuf::from(self.local_root.as_ref().unwrap())
4740            .join(&self.root_name)
4741            .join(self.path.as_ref())
4742    }
4743
4744    fn load(&self, _cx: &App) -> Task<Result<String>> {
4745        unimplemented!()
4746    }
4747
4748    fn load_bytes(&self, _cx: &App) -> Task<Result<Vec<u8>>> {
4749        unimplemented!()
4750    }
4751}
4752
4753pub(crate) fn contiguous_ranges(
4754    values: impl Iterator<Item = u32>,
4755    max_len: usize,
4756) -> impl Iterator<Item = Range<u32>> {
4757    let mut values = values;
4758    let mut current_range: Option<Range<u32>> = None;
4759    std::iter::from_fn(move || {
4760        loop {
4761            if let Some(value) = values.next() {
4762                if let Some(range) = &mut current_range {
4763                    if value == range.end && range.len() < max_len {
4764                        range.end += 1;
4765                        continue;
4766                    }
4767                }
4768
4769                let prev_range = current_range.clone();
4770                current_range = Some(value..(value + 1));
4771                if prev_range.is_some() {
4772                    return prev_range;
4773                }
4774            } else {
4775                return current_range.take();
4776            }
4777        }
4778    })
4779}
4780
4781#[derive(Default, Debug)]
4782pub struct CharClassifier {
4783    scope: Option<LanguageScope>,
4784    for_completion: bool,
4785    ignore_punctuation: bool,
4786}
4787
4788impl CharClassifier {
4789    pub fn new(scope: Option<LanguageScope>) -> Self {
4790        Self {
4791            scope,
4792            for_completion: false,
4793            ignore_punctuation: false,
4794        }
4795    }
4796
4797    pub fn for_completion(self, for_completion: bool) -> Self {
4798        Self {
4799            for_completion,
4800            ..self
4801        }
4802    }
4803
4804    pub fn ignore_punctuation(self, ignore_punctuation: bool) -> Self {
4805        Self {
4806            ignore_punctuation,
4807            ..self
4808        }
4809    }
4810
4811    pub fn is_whitespace(&self, c: char) -> bool {
4812        self.kind(c) == CharKind::Whitespace
4813    }
4814
4815    pub fn is_word(&self, c: char) -> bool {
4816        self.kind(c) == CharKind::Word
4817    }
4818
4819    pub fn is_punctuation(&self, c: char) -> bool {
4820        self.kind(c) == CharKind::Punctuation
4821    }
4822
4823    pub fn kind_with(&self, c: char, ignore_punctuation: bool) -> CharKind {
4824        if c.is_alphanumeric() || c == '_' {
4825            return CharKind::Word;
4826        }
4827
4828        if let Some(scope) = &self.scope {
4829            let characters = if self.for_completion {
4830                scope.completion_query_characters()
4831            } else {
4832                scope.word_characters()
4833            };
4834            if let Some(characters) = characters {
4835                if characters.contains(&c) {
4836                    return CharKind::Word;
4837                }
4838            }
4839        }
4840
4841        if c.is_whitespace() {
4842            return CharKind::Whitespace;
4843        }
4844
4845        if ignore_punctuation {
4846            CharKind::Word
4847        } else {
4848            CharKind::Punctuation
4849        }
4850    }
4851
4852    pub fn kind(&self, c: char) -> CharKind {
4853        self.kind_with(c, self.ignore_punctuation)
4854    }
4855}
4856
4857/// Find all of the ranges of whitespace that occur at the ends of lines
4858/// in the given rope.
4859///
4860/// This could also be done with a regex search, but this implementation
4861/// avoids copying text.
4862pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
4863    let mut ranges = Vec::new();
4864
4865    let mut offset = 0;
4866    let mut prev_chunk_trailing_whitespace_range = 0..0;
4867    for chunk in rope.chunks() {
4868        let mut prev_line_trailing_whitespace_range = 0..0;
4869        for (i, line) in chunk.split('\n').enumerate() {
4870            let line_end_offset = offset + line.len();
4871            let trimmed_line_len = line.trim_end_matches([' ', '\t']).len();
4872            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
4873
4874            if i == 0 && trimmed_line_len == 0 {
4875                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
4876            }
4877            if !prev_line_trailing_whitespace_range.is_empty() {
4878                ranges.push(prev_line_trailing_whitespace_range);
4879            }
4880
4881            offset = line_end_offset + 1;
4882            prev_line_trailing_whitespace_range = trailing_whitespace_range;
4883        }
4884
4885        offset -= 1;
4886        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
4887    }
4888
4889    if !prev_chunk_trailing_whitespace_range.is_empty() {
4890        ranges.push(prev_chunk_trailing_whitespace_range);
4891    }
4892
4893    ranges
4894}