buffer.rs

   1pub use crate::{
   2    diagnostic_set::DiagnosticSet,
   3    highlight_map::{HighlightId, HighlightMap},
   4    proto, Grammar, Language, LanguageRegistry,
   5};
   6use crate::{
   7    diagnostic_set::{DiagnosticEntry, DiagnosticGroup},
   8    language_settings::{language_settings, LanguageSettings},
   9    outline::OutlineItem,
  10    syntax_map::{
  11        SyntaxLayer, SyntaxMap, SyntaxMapCapture, SyntaxMapCaptures, SyntaxMapMatch,
  12        SyntaxMapMatches, SyntaxSnapshot, ToTreeSitterPoint,
  13    },
  14    task_context::RunnableRange,
  15    text_diff::text_diff,
  16    LanguageScope, Outline, OutlineConfig, RunnableCapture, RunnableTag, TextObject,
  17    TreeSitterOptions,
  18};
  19use anyhow::{anyhow, Context as _, Result};
  20use async_watch as watch;
  21use clock::Lamport;
  22pub use clock::ReplicaId;
  23use collections::HashMap;
  24use fs::MTime;
  25use futures::channel::oneshot;
  26use gpui::{
  27    AnyElement, App, AppContext as _, Context, Entity, EventEmitter, HighlightStyle, Pixels,
  28    SharedString, StyledText, Task, TaskLabel, TextStyle, Window,
  29};
  30use lsp::{LanguageServerId, NumberOrString};
  31use parking_lot::Mutex;
  32use schemars::JsonSchema;
  33use serde::{Deserialize, Serialize};
  34use serde_json::Value;
  35use settings::WorktreeId;
  36use smallvec::SmallVec;
  37use smol::future::yield_now;
  38use std::{
  39    any::Any,
  40    borrow::Cow,
  41    cell::Cell,
  42    cmp::{self, Ordering, Reverse},
  43    collections::{BTreeMap, BTreeSet},
  44    ffi::OsStr,
  45    fmt,
  46    future::Future,
  47    iter::{self, Iterator, Peekable},
  48    mem,
  49    num::NonZeroU32,
  50    ops::{Deref, DerefMut, Range},
  51    path::{Path, PathBuf},
  52    rc, str,
  53    sync::{Arc, LazyLock},
  54    time::{Duration, Instant},
  55    vec,
  56};
  57use sum_tree::TreeMap;
  58use text::operation_queue::OperationQueue;
  59use text::*;
  60pub use text::{
  61    Anchor, Bias, Buffer as TextBuffer, BufferId, BufferSnapshot as TextBufferSnapshot, Edit,
  62    OffsetRangeExt, OffsetUtf16, Patch, Point, PointUtf16, Rope, Selection, SelectionGoal,
  63    Subscription, TextDimension, TextSummary, ToOffset, ToOffsetUtf16, ToPoint, ToPointUtf16,
  64    Transaction, TransactionId, Unclipped,
  65};
  66use theme::{ActiveTheme as _, SyntaxTheme};
  67#[cfg(any(test, feature = "test-support"))]
  68use util::RandomCharIter;
  69use util::{debug_panic, maybe, RangeExt};
  70
  71#[cfg(any(test, feature = "test-support"))]
  72pub use {tree_sitter_rust, tree_sitter_typescript};
  73
  74pub use lsp::DiagnosticSeverity;
  75
  76/// A label for the background task spawned by the buffer to compute
  77/// a diff against the contents of its file.
  78pub static BUFFER_DIFF_TASK: LazyLock<TaskLabel> = LazyLock::new(TaskLabel::new);
  79
  80/// Indicate whether a [`Buffer`] has permissions to edit.
  81#[derive(PartialEq, Clone, Copy, Debug)]
  82pub enum Capability {
  83    /// The buffer is a mutable replica.
  84    ReadWrite,
  85    /// The buffer is a read-only replica.
  86    ReadOnly,
  87}
  88
  89pub type BufferRow = u32;
  90
  91/// An in-memory representation of a source code file, including its text,
  92/// syntax trees, git status, and diagnostics.
  93pub struct Buffer {
  94    text: TextBuffer,
  95    branch_state: Option<BufferBranchState>,
  96    /// Filesystem state, `None` when there is no path.
  97    file: Option<Arc<dyn File>>,
  98    /// The mtime of the file when this buffer was last loaded from
  99    /// or saved to disk.
 100    saved_mtime: Option<MTime>,
 101    /// The version vector when this buffer was last loaded from
 102    /// or saved to disk.
 103    saved_version: clock::Global,
 104    preview_version: clock::Global,
 105    transaction_depth: usize,
 106    was_dirty_before_starting_transaction: Option<bool>,
 107    reload_task: Option<Task<Result<()>>>,
 108    language: Option<Arc<Language>>,
 109    autoindent_requests: Vec<Arc<AutoindentRequest>>,
 110    pending_autoindent: Option<Task<()>>,
 111    sync_parse_timeout: Duration,
 112    syntax_map: Mutex<SyntaxMap>,
 113    reparse: Option<Task<()>>,
 114    parse_status: (watch::Sender<ParseStatus>, watch::Receiver<ParseStatus>),
 115    non_text_state_update_count: usize,
 116    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 117    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 118    diagnostics_timestamp: clock::Lamport,
 119    completion_triggers: BTreeSet<String>,
 120    completion_triggers_per_language_server: HashMap<LanguageServerId, BTreeSet<String>>,
 121    completion_triggers_timestamp: clock::Lamport,
 122    deferred_ops: OperationQueue<Operation>,
 123    capability: Capability,
 124    has_conflict: bool,
 125    /// Memoize calls to has_changes_since(saved_version).
 126    /// The contents of a cell are (self.version, has_changes) at the time of a last call.
 127    has_unsaved_edits: Cell<(clock::Global, bool)>,
 128    change_bits: Vec<rc::Weak<Cell<bool>>>,
 129    _subscriptions: Vec<gpui::Subscription>,
 130}
 131
 132#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 133pub enum ParseStatus {
 134    Idle,
 135    Parsing,
 136}
 137
 138struct BufferBranchState {
 139    base_buffer: Entity<Buffer>,
 140    merged_operations: Vec<Lamport>,
 141}
 142
 143/// An immutable, cheaply cloneable representation of a fixed
 144/// state of a buffer.
 145pub struct BufferSnapshot {
 146    pub text: text::BufferSnapshot,
 147    pub(crate) syntax: SyntaxSnapshot,
 148    file: Option<Arc<dyn File>>,
 149    diagnostics: SmallVec<[(LanguageServerId, DiagnosticSet); 2]>,
 150    remote_selections: TreeMap<ReplicaId, SelectionSet>,
 151    language: Option<Arc<Language>>,
 152    non_text_state_update_count: usize,
 153}
 154
 155/// The kind and amount of indentation in a particular line. For now,
 156/// assumes that indentation is all the same character.
 157#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 158pub struct IndentSize {
 159    /// The number of bytes that comprise the indentation.
 160    pub len: u32,
 161    /// The kind of whitespace used for indentation.
 162    pub kind: IndentKind,
 163}
 164
 165/// A whitespace character that's used for indentation.
 166#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Default)]
 167pub enum IndentKind {
 168    /// An ASCII space character.
 169    #[default]
 170    Space,
 171    /// An ASCII tab character.
 172    Tab,
 173}
 174
 175/// The shape of a selection cursor.
 176#[derive(Copy, Clone, Debug, Default, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 177#[serde(rename_all = "snake_case")]
 178pub enum CursorShape {
 179    /// A vertical bar
 180    #[default]
 181    Bar,
 182    /// A block that surrounds the following character
 183    Block,
 184    /// An underline that runs along the following character
 185    Underline,
 186    /// A box drawn around the following character
 187    Hollow,
 188}
 189
 190#[derive(Clone, Debug)]
 191struct SelectionSet {
 192    line_mode: bool,
 193    cursor_shape: CursorShape,
 194    selections: Arc<[Selection<Anchor>]>,
 195    lamport_timestamp: clock::Lamport,
 196}
 197
 198/// A diagnostic associated with a certain range of a buffer.
 199#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 200pub struct Diagnostic {
 201    /// The name of the service that produced this diagnostic.
 202    pub source: Option<String>,
 203    /// A machine-readable code that identifies this diagnostic.
 204    pub code: Option<NumberOrString>,
 205    /// Whether this diagnostic is a hint, warning, or error.
 206    pub severity: DiagnosticSeverity,
 207    /// The human-readable message associated with this diagnostic.
 208    pub message: String,
 209    /// An id that identifies the group to which this diagnostic belongs.
 210    ///
 211    /// When a language server produces a diagnostic with
 212    /// one or more associated diagnostics, those diagnostics are all
 213    /// assigned a single group ID.
 214    pub group_id: usize,
 215    /// Whether this diagnostic is the primary diagnostic for its group.
 216    ///
 217    /// In a given group, the primary diagnostic is the top-level diagnostic
 218    /// returned by the language server. The non-primary diagnostics are the
 219    /// associated diagnostics.
 220    pub is_primary: bool,
 221    /// Whether this diagnostic is considered to originate from an analysis of
 222    /// files on disk, as opposed to any unsaved buffer contents. This is a
 223    /// property of a given diagnostic source, and is configured for a given
 224    /// language server via the [`LspAdapter::disk_based_diagnostic_sources`](crate::LspAdapter::disk_based_diagnostic_sources) method
 225    /// for the language server.
 226    pub is_disk_based: bool,
 227    /// Whether this diagnostic marks unnecessary code.
 228    pub is_unnecessary: bool,
 229    /// Data from language server that produced this diagnostic. Passed back to the LS when we request code actions for this diagnostic.
 230    pub data: Option<Value>,
 231}
 232
 233/// An operation used to synchronize this buffer with its other replicas.
 234#[derive(Clone, Debug, PartialEq)]
 235pub enum Operation {
 236    /// A text operation.
 237    Buffer(text::Operation),
 238
 239    /// An update to the buffer's diagnostics.
 240    UpdateDiagnostics {
 241        /// The id of the language server that produced the new diagnostics.
 242        server_id: LanguageServerId,
 243        /// The diagnostics.
 244        diagnostics: Arc<[DiagnosticEntry<Anchor>]>,
 245        /// The buffer's lamport timestamp.
 246        lamport_timestamp: clock::Lamport,
 247    },
 248
 249    /// An update to the most recent selections in this buffer.
 250    UpdateSelections {
 251        /// The selections.
 252        selections: Arc<[Selection<Anchor>]>,
 253        /// The buffer's lamport timestamp.
 254        lamport_timestamp: clock::Lamport,
 255        /// Whether the selections are in 'line mode'.
 256        line_mode: bool,
 257        /// The [`CursorShape`] associated with these selections.
 258        cursor_shape: CursorShape,
 259    },
 260
 261    /// An update to the characters that should trigger autocompletion
 262    /// for this buffer.
 263    UpdateCompletionTriggers {
 264        /// The characters that trigger autocompletion.
 265        triggers: Vec<String>,
 266        /// The buffer's lamport timestamp.
 267        lamport_timestamp: clock::Lamport,
 268        /// The language server ID.
 269        server_id: LanguageServerId,
 270    },
 271}
 272
 273/// An event that occurs in a buffer.
 274#[derive(Clone, Debug, PartialEq)]
 275pub enum BufferEvent {
 276    /// The buffer was changed in a way that must be
 277    /// propagated to its other replicas.
 278    Operation {
 279        operation: Operation,
 280        is_local: bool,
 281    },
 282    /// The buffer was edited.
 283    Edited,
 284    /// The buffer's `dirty` bit changed.
 285    DirtyChanged,
 286    /// The buffer was saved.
 287    Saved,
 288    /// The buffer's file was changed on disk.
 289    FileHandleChanged,
 290    /// The buffer was reloaded.
 291    Reloaded,
 292    /// The buffer is in need of a reload
 293    ReloadNeeded,
 294    /// The buffer's language was changed.
 295    LanguageChanged,
 296    /// The buffer's syntax trees were updated.
 297    Reparsed,
 298    /// The buffer's diagnostics were updated.
 299    DiagnosticsUpdated,
 300    /// The buffer gained or lost editing capabilities.
 301    CapabilityChanged,
 302    /// The buffer was explicitly requested to close.
 303    Closed,
 304    /// The buffer was discarded when closing.
 305    Discarded,
 306}
 307
 308/// The file associated with a buffer.
 309pub trait File: Send + Sync {
 310    /// Returns the [`LocalFile`] associated with this file, if the
 311    /// file is local.
 312    fn as_local(&self) -> Option<&dyn LocalFile>;
 313
 314    /// Returns whether this file is local.
 315    fn is_local(&self) -> bool {
 316        self.as_local().is_some()
 317    }
 318
 319    /// Returns whether the file is new, exists in storage, or has been deleted. Includes metadata
 320    /// only available in some states, such as modification time.
 321    fn disk_state(&self) -> DiskState;
 322
 323    /// Returns the path of this file relative to the worktree's root directory.
 324    fn path(&self) -> &Arc<Path>;
 325
 326    /// Returns the path of this file relative to the worktree's parent directory (this means it
 327    /// includes the name of the worktree's root folder).
 328    fn full_path(&self, cx: &App) -> PathBuf;
 329
 330    /// Returns the last component of this handle's absolute path. If this handle refers to the root
 331    /// of its worktree, then this method will return the name of the worktree itself.
 332    fn file_name<'a>(&'a self, cx: &'a App) -> &'a OsStr;
 333
 334    /// Returns the id of the worktree to which this file belongs.
 335    ///
 336    /// This is needed for looking up project-specific settings.
 337    fn worktree_id(&self, cx: &App) -> WorktreeId;
 338
 339    /// Converts this file into an [`Any`] trait object.
 340    fn as_any(&self) -> &dyn Any;
 341
 342    /// Converts this file into a protobuf message.
 343    fn to_proto(&self, cx: &App) -> rpc::proto::File;
 344
 345    /// Return whether Zed considers this to be a private file.
 346    fn is_private(&self) -> bool;
 347}
 348
 349/// The file's storage status - whether it's stored (`Present`), and if so when it was last
 350/// modified. In the case where the file is not stored, it can be either `New` or `Deleted`. In the
 351/// UI these two states are distinguished. For example, the buffer tab does not display a deletion
 352/// indicator for new files.
 353#[derive(Copy, Clone, Debug, PartialEq)]
 354pub enum DiskState {
 355    /// File created in Zed that has not been saved.
 356    New,
 357    /// File present on the filesystem.
 358    Present { mtime: MTime },
 359    /// Deleted file that was previously present.
 360    Deleted,
 361}
 362
 363impl DiskState {
 364    /// Returns the file's last known modification time on disk.
 365    pub fn mtime(self) -> Option<MTime> {
 366        match self {
 367            DiskState::New => None,
 368            DiskState::Present { mtime } => Some(mtime),
 369            DiskState::Deleted => None,
 370        }
 371    }
 372
 373    pub fn exists(&self) -> bool {
 374        match self {
 375            DiskState::New => false,
 376            DiskState::Present { .. } => true,
 377            DiskState::Deleted => false,
 378        }
 379    }
 380}
 381
 382/// The file associated with a buffer, in the case where the file is on the local disk.
 383pub trait LocalFile: File {
 384    /// Returns the absolute path of this file
 385    fn abs_path(&self, cx: &App) -> PathBuf;
 386
 387    /// Loads the file contents from disk and returns them as a UTF-8 encoded string.
 388    fn load(&self, cx: &App) -> Task<Result<String>>;
 389
 390    /// Loads the file's contents from disk.
 391    fn load_bytes(&self, cx: &App) -> Task<Result<Vec<u8>>>;
 392}
 393
 394/// The auto-indent behavior associated with an editing operation.
 395/// For some editing operations, each affected line of text has its
 396/// indentation recomputed. For other operations, the entire block
 397/// of edited text is adjusted uniformly.
 398#[derive(Clone, Debug)]
 399pub enum AutoindentMode {
 400    /// Indent each line of inserted text.
 401    EachLine,
 402    /// Apply the same indentation adjustment to all of the lines
 403    /// in a given insertion.
 404    Block {
 405        /// The original indentation column of the first line of each
 406        /// insertion, if it has been copied.
 407        ///
 408        /// Knowing this makes it possible to preserve the relative indentation
 409        /// of every line in the insertion from when it was copied.
 410        ///
 411        /// If the original indent column is `a`, and the first line of insertion
 412        /// is then auto-indented to column `b`, then every other line of
 413        /// the insertion will be auto-indented to column `b - a`
 414        original_indent_columns: Vec<Option<u32>>,
 415    },
 416}
 417
 418#[derive(Clone)]
 419struct AutoindentRequest {
 420    before_edit: BufferSnapshot,
 421    entries: Vec<AutoindentRequestEntry>,
 422    is_block_mode: bool,
 423    ignore_empty_lines: bool,
 424}
 425
 426#[derive(Debug, Clone)]
 427struct AutoindentRequestEntry {
 428    /// A range of the buffer whose indentation should be adjusted.
 429    range: Range<Anchor>,
 430    /// Whether or not these lines should be considered brand new, for the
 431    /// purpose of auto-indent. When text is not new, its indentation will
 432    /// only be adjusted if the suggested indentation level has *changed*
 433    /// since the edit was made.
 434    first_line_is_new: bool,
 435    indent_size: IndentSize,
 436    original_indent_column: Option<u32>,
 437}
 438
 439#[derive(Debug)]
 440struct IndentSuggestion {
 441    basis_row: u32,
 442    delta: Ordering,
 443    within_error: bool,
 444}
 445
 446struct BufferChunkHighlights<'a> {
 447    captures: SyntaxMapCaptures<'a>,
 448    next_capture: Option<SyntaxMapCapture<'a>>,
 449    stack: Vec<(usize, HighlightId)>,
 450    highlight_maps: Vec<HighlightMap>,
 451}
 452
 453/// An iterator that yields chunks of a buffer's text, along with their
 454/// syntax highlights and diagnostic status.
 455pub struct BufferChunks<'a> {
 456    buffer_snapshot: Option<&'a BufferSnapshot>,
 457    range: Range<usize>,
 458    chunks: text::Chunks<'a>,
 459    diagnostic_endpoints: Option<Peekable<vec::IntoIter<DiagnosticEndpoint>>>,
 460    error_depth: usize,
 461    warning_depth: usize,
 462    information_depth: usize,
 463    hint_depth: usize,
 464    unnecessary_depth: usize,
 465    highlights: Option<BufferChunkHighlights<'a>>,
 466}
 467
 468/// A chunk of a buffer's text, along with its syntax highlight and
 469/// diagnostic status.
 470#[derive(Clone, Debug, Default)]
 471pub struct Chunk<'a> {
 472    /// The text of the chunk.
 473    pub text: &'a str,
 474    /// The syntax highlighting style of the chunk.
 475    pub syntax_highlight_id: Option<HighlightId>,
 476    /// The highlight style that has been applied to this chunk in
 477    /// the editor.
 478    pub highlight_style: Option<HighlightStyle>,
 479    /// The severity of diagnostic associated with this chunk, if any.
 480    pub diagnostic_severity: Option<DiagnosticSeverity>,
 481    /// Whether this chunk of text is marked as unnecessary.
 482    pub is_unnecessary: bool,
 483    /// Whether this chunk of text was originally a tab character.
 484    pub is_tab: bool,
 485    /// An optional recipe for how the chunk should be presented.
 486    pub renderer: Option<ChunkRenderer>,
 487}
 488
 489/// A recipe for how the chunk should be presented.
 490#[derive(Clone)]
 491pub struct ChunkRenderer {
 492    /// creates a custom element to represent this chunk.
 493    pub render: Arc<dyn Send + Sync + Fn(&mut ChunkRendererContext) -> AnyElement>,
 494    /// If true, the element is constrained to the shaped width of the text.
 495    pub constrain_width: bool,
 496}
 497
 498pub struct ChunkRendererContext<'a, 'b> {
 499    pub window: &'a mut Window,
 500    pub context: &'b mut App,
 501    pub max_width: Pixels,
 502}
 503
 504impl fmt::Debug for ChunkRenderer {
 505    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 506        f.debug_struct("ChunkRenderer")
 507            .field("constrain_width", &self.constrain_width)
 508            .finish()
 509    }
 510}
 511
 512impl Deref for ChunkRendererContext<'_, '_> {
 513    type Target = App;
 514
 515    fn deref(&self) -> &Self::Target {
 516        self.context
 517    }
 518}
 519
 520impl DerefMut for ChunkRendererContext<'_, '_> {
 521    fn deref_mut(&mut self) -> &mut Self::Target {
 522        self.context
 523    }
 524}
 525
 526/// A set of edits to a given version of a buffer, computed asynchronously.
 527#[derive(Debug)]
 528pub struct Diff {
 529    pub(crate) base_version: clock::Global,
 530    line_ending: LineEnding,
 531    pub edits: Vec<(Range<usize>, Arc<str>)>,
 532}
 533
 534#[derive(Clone, Copy)]
 535pub(crate) struct DiagnosticEndpoint {
 536    offset: usize,
 537    is_start: bool,
 538    severity: DiagnosticSeverity,
 539    is_unnecessary: bool,
 540}
 541
 542/// A class of characters, used for characterizing a run of text.
 543#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Debug)]
 544pub enum CharKind {
 545    /// Whitespace.
 546    Whitespace,
 547    /// Punctuation.
 548    Punctuation,
 549    /// Word.
 550    Word,
 551}
 552
 553/// A runnable is a set of data about a region that could be resolved into a task
 554pub struct Runnable {
 555    pub tags: SmallVec<[RunnableTag; 1]>,
 556    pub language: Arc<Language>,
 557    pub buffer: BufferId,
 558}
 559
 560#[derive(Default, Clone, Debug)]
 561pub struct HighlightedText {
 562    pub text: SharedString,
 563    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 564}
 565
 566#[derive(Default, Debug)]
 567struct HighlightedTextBuilder {
 568    pub text: String,
 569    pub highlights: Vec<(Range<usize>, HighlightStyle)>,
 570}
 571
 572impl HighlightedText {
 573    pub fn from_buffer_range<T: ToOffset>(
 574        range: Range<T>,
 575        snapshot: &text::BufferSnapshot,
 576        syntax_snapshot: &SyntaxSnapshot,
 577        override_style: Option<HighlightStyle>,
 578        syntax_theme: &SyntaxTheme,
 579    ) -> Self {
 580        let mut highlighted_text = HighlightedTextBuilder::default();
 581        highlighted_text.add_text_from_buffer_range(
 582            range,
 583            snapshot,
 584            syntax_snapshot,
 585            override_style,
 586            syntax_theme,
 587        );
 588        highlighted_text.build()
 589    }
 590
 591    pub fn to_styled_text(&self, default_style: &TextStyle) -> StyledText {
 592        gpui::StyledText::new(self.text.clone())
 593            .with_default_highlights(default_style, self.highlights.iter().cloned())
 594    }
 595
 596    /// Returns the first line without leading whitespace unless highlighted
 597    /// and a boolean indicating if there are more lines after
 598    pub fn first_line_preview(self) -> (Self, bool) {
 599        let newline_ix = self.text.find('\n').unwrap_or(self.text.len());
 600        let first_line = &self.text[..newline_ix];
 601
 602        // Trim leading whitespace, unless an edit starts prior to it.
 603        let mut preview_start_ix = first_line.len() - first_line.trim_start().len();
 604        if let Some((first_highlight_range, _)) = self.highlights.first() {
 605            preview_start_ix = preview_start_ix.min(first_highlight_range.start);
 606        }
 607
 608        let preview_text = &first_line[preview_start_ix..];
 609        let preview_highlights = self
 610            .highlights
 611            .into_iter()
 612            .take_while(|(range, _)| range.start < newline_ix)
 613            .filter_map(|(mut range, highlight)| {
 614                range.start = range.start.saturating_sub(preview_start_ix);
 615                range.end = range.end.saturating_sub(preview_start_ix).min(newline_ix);
 616                if range.is_empty() {
 617                    None
 618                } else {
 619                    Some((range, highlight))
 620                }
 621            });
 622
 623        let preview = Self {
 624            text: SharedString::new(preview_text),
 625            highlights: preview_highlights.collect(),
 626        };
 627
 628        (preview, self.text.len() > newline_ix)
 629    }
 630}
 631
 632impl HighlightedTextBuilder {
 633    pub fn build(self) -> HighlightedText {
 634        HighlightedText {
 635            text: self.text.into(),
 636            highlights: self.highlights,
 637        }
 638    }
 639
 640    pub fn add_text_from_buffer_range<T: ToOffset>(
 641        &mut self,
 642        range: Range<T>,
 643        snapshot: &text::BufferSnapshot,
 644        syntax_snapshot: &SyntaxSnapshot,
 645        override_style: Option<HighlightStyle>,
 646        syntax_theme: &SyntaxTheme,
 647    ) {
 648        let range = range.to_offset(snapshot);
 649        for chunk in Self::highlighted_chunks(range, snapshot, syntax_snapshot) {
 650            let start = self.text.len();
 651            self.text.push_str(chunk.text);
 652            let end = self.text.len();
 653
 654            if let Some(mut highlight_style) = chunk
 655                .syntax_highlight_id
 656                .and_then(|id| id.style(syntax_theme))
 657            {
 658                if let Some(override_style) = override_style {
 659                    highlight_style.highlight(override_style);
 660                }
 661                self.highlights.push((start..end, highlight_style));
 662            } else if let Some(override_style) = override_style {
 663                self.highlights.push((start..end, override_style));
 664            }
 665        }
 666    }
 667
 668    fn highlighted_chunks<'a>(
 669        range: Range<usize>,
 670        snapshot: &'a text::BufferSnapshot,
 671        syntax_snapshot: &'a SyntaxSnapshot,
 672    ) -> BufferChunks<'a> {
 673        let captures = syntax_snapshot.captures(range.clone(), snapshot, |grammar| {
 674            grammar.highlights_query.as_ref()
 675        });
 676
 677        let highlight_maps = captures
 678            .grammars()
 679            .iter()
 680            .map(|grammar| grammar.highlight_map())
 681            .collect();
 682
 683        BufferChunks::new(
 684            snapshot.as_rope(),
 685            range,
 686            Some((captures, highlight_maps)),
 687            false,
 688            None,
 689        )
 690    }
 691}
 692
 693#[derive(Clone)]
 694pub struct EditPreview {
 695    old_snapshot: text::BufferSnapshot,
 696    applied_edits_snapshot: text::BufferSnapshot,
 697    syntax_snapshot: SyntaxSnapshot,
 698}
 699
 700impl EditPreview {
 701    pub fn highlight_edits(
 702        &self,
 703        current_snapshot: &BufferSnapshot,
 704        edits: &[(Range<Anchor>, String)],
 705        include_deletions: bool,
 706        cx: &App,
 707    ) -> HighlightedText {
 708        let Some(visible_range_in_preview_snapshot) = self.compute_visible_range(edits) else {
 709            return HighlightedText::default();
 710        };
 711
 712        let mut highlighted_text = HighlightedTextBuilder::default();
 713
 714        let mut offset_in_preview_snapshot = visible_range_in_preview_snapshot.start;
 715
 716        let insertion_highlight_style = HighlightStyle {
 717            background_color: Some(cx.theme().status().created_background),
 718            ..Default::default()
 719        };
 720        let deletion_highlight_style = HighlightStyle {
 721            background_color: Some(cx.theme().status().deleted_background),
 722            ..Default::default()
 723        };
 724        let syntax_theme = cx.theme().syntax();
 725
 726        for (range, edit_text) in edits {
 727            let edit_new_end_in_preview_snapshot = range
 728                .end
 729                .bias_right(&self.old_snapshot)
 730                .to_offset(&self.applied_edits_snapshot);
 731            let edit_start_in_preview_snapshot = edit_new_end_in_preview_snapshot - edit_text.len();
 732
 733            let unchanged_range_in_preview_snapshot =
 734                offset_in_preview_snapshot..edit_start_in_preview_snapshot;
 735            if !unchanged_range_in_preview_snapshot.is_empty() {
 736                highlighted_text.add_text_from_buffer_range(
 737                    unchanged_range_in_preview_snapshot,
 738                    &self.applied_edits_snapshot,
 739                    &self.syntax_snapshot,
 740                    None,
 741                    &syntax_theme,
 742                );
 743            }
 744
 745            let range_in_current_snapshot = range.to_offset(current_snapshot);
 746            if include_deletions && !range_in_current_snapshot.is_empty() {
 747                highlighted_text.add_text_from_buffer_range(
 748                    range_in_current_snapshot,
 749                    &current_snapshot.text,
 750                    &current_snapshot.syntax,
 751                    Some(deletion_highlight_style),
 752                    &syntax_theme,
 753                );
 754            }
 755
 756            if !edit_text.is_empty() {
 757                highlighted_text.add_text_from_buffer_range(
 758                    edit_start_in_preview_snapshot..edit_new_end_in_preview_snapshot,
 759                    &self.applied_edits_snapshot,
 760                    &self.syntax_snapshot,
 761                    Some(insertion_highlight_style),
 762                    &syntax_theme,
 763                );
 764            }
 765
 766            offset_in_preview_snapshot = edit_new_end_in_preview_snapshot;
 767        }
 768
 769        highlighted_text.add_text_from_buffer_range(
 770            offset_in_preview_snapshot..visible_range_in_preview_snapshot.end,
 771            &self.applied_edits_snapshot,
 772            &self.syntax_snapshot,
 773            None,
 774            &syntax_theme,
 775        );
 776
 777        highlighted_text.build()
 778    }
 779
 780    fn compute_visible_range(&self, edits: &[(Range<Anchor>, String)]) -> Option<Range<usize>> {
 781        let (first, _) = edits.first()?;
 782        let (last, _) = edits.last()?;
 783
 784        let start = first
 785            .start
 786            .bias_left(&self.old_snapshot)
 787            .to_point(&self.applied_edits_snapshot);
 788        let end = last
 789            .end
 790            .bias_right(&self.old_snapshot)
 791            .to_point(&self.applied_edits_snapshot);
 792
 793        // Ensure that the first line of the first edit and the last line of the last edit are always fully visible
 794        let range = Point::new(start.row, 0)
 795            ..Point::new(end.row, self.applied_edits_snapshot.line_len(end.row));
 796
 797        Some(range.to_offset(&self.applied_edits_snapshot))
 798    }
 799}
 800
 801#[derive(Clone, Debug, PartialEq, Eq)]
 802pub struct BracketMatch {
 803    pub open_range: Range<usize>,
 804    pub close_range: Range<usize>,
 805    pub newline_only: bool,
 806}
 807
 808impl Buffer {
 809    /// Create a new buffer with the given base text.
 810    pub fn local<T: Into<String>>(base_text: T, cx: &Context<Self>) -> Self {
 811        Self::build(
 812            TextBuffer::new(0, cx.entity_id().as_non_zero_u64().into(), base_text.into()),
 813            None,
 814            Capability::ReadWrite,
 815        )
 816    }
 817
 818    /// Create a new buffer with the given base text that has proper line endings and other normalization applied.
 819    pub fn local_normalized(
 820        base_text_normalized: Rope,
 821        line_ending: LineEnding,
 822        cx: &Context<Self>,
 823    ) -> Self {
 824        Self::build(
 825            TextBuffer::new_normalized(
 826                0,
 827                cx.entity_id().as_non_zero_u64().into(),
 828                line_ending,
 829                base_text_normalized,
 830            ),
 831            None,
 832            Capability::ReadWrite,
 833        )
 834    }
 835
 836    /// Create a new buffer that is a replica of a remote buffer.
 837    pub fn remote(
 838        remote_id: BufferId,
 839        replica_id: ReplicaId,
 840        capability: Capability,
 841        base_text: impl Into<String>,
 842    ) -> Self {
 843        Self::build(
 844            TextBuffer::new(replica_id, remote_id, base_text.into()),
 845            None,
 846            capability,
 847        )
 848    }
 849
 850    /// Create a new buffer that is a replica of a remote buffer, populating its
 851    /// state from the given protobuf message.
 852    pub fn from_proto(
 853        replica_id: ReplicaId,
 854        capability: Capability,
 855        message: proto::BufferState,
 856        file: Option<Arc<dyn File>>,
 857    ) -> Result<Self> {
 858        let buffer_id = BufferId::new(message.id)
 859            .with_context(|| anyhow!("Could not deserialize buffer_id"))?;
 860        let buffer = TextBuffer::new(replica_id, buffer_id, message.base_text);
 861        let mut this = Self::build(buffer, file, capability);
 862        this.text.set_line_ending(proto::deserialize_line_ending(
 863            rpc::proto::LineEnding::from_i32(message.line_ending)
 864                .ok_or_else(|| anyhow!("missing line_ending"))?,
 865        ));
 866        this.saved_version = proto::deserialize_version(&message.saved_version);
 867        this.saved_mtime = message.saved_mtime.map(|time| time.into());
 868        Ok(this)
 869    }
 870
 871    /// Serialize the buffer's state to a protobuf message.
 872    pub fn to_proto(&self, cx: &App) -> proto::BufferState {
 873        proto::BufferState {
 874            id: self.remote_id().into(),
 875            file: self.file.as_ref().map(|f| f.to_proto(cx)),
 876            base_text: self.base_text().to_string(),
 877            line_ending: proto::serialize_line_ending(self.line_ending()) as i32,
 878            saved_version: proto::serialize_version(&self.saved_version),
 879            saved_mtime: self.saved_mtime.map(|time| time.into()),
 880        }
 881    }
 882
 883    /// Serialize as protobufs all of the changes to the buffer since the given version.
 884    pub fn serialize_ops(
 885        &self,
 886        since: Option<clock::Global>,
 887        cx: &App,
 888    ) -> Task<Vec<proto::Operation>> {
 889        let mut operations = Vec::new();
 890        operations.extend(self.deferred_ops.iter().map(proto::serialize_operation));
 891
 892        operations.extend(self.remote_selections.iter().map(|(_, set)| {
 893            proto::serialize_operation(&Operation::UpdateSelections {
 894                selections: set.selections.clone(),
 895                lamport_timestamp: set.lamport_timestamp,
 896                line_mode: set.line_mode,
 897                cursor_shape: set.cursor_shape,
 898            })
 899        }));
 900
 901        for (server_id, diagnostics) in &self.diagnostics {
 902            operations.push(proto::serialize_operation(&Operation::UpdateDiagnostics {
 903                lamport_timestamp: self.diagnostics_timestamp,
 904                server_id: *server_id,
 905                diagnostics: diagnostics.iter().cloned().collect(),
 906            }));
 907        }
 908
 909        for (server_id, completions) in &self.completion_triggers_per_language_server {
 910            operations.push(proto::serialize_operation(
 911                &Operation::UpdateCompletionTriggers {
 912                    triggers: completions.iter().cloned().collect(),
 913                    lamport_timestamp: self.completion_triggers_timestamp,
 914                    server_id: *server_id,
 915                },
 916            ));
 917        }
 918
 919        let text_operations = self.text.operations().clone();
 920        cx.background_spawn(async move {
 921            let since = since.unwrap_or_default();
 922            operations.extend(
 923                text_operations
 924                    .iter()
 925                    .filter(|(_, op)| !since.observed(op.timestamp()))
 926                    .map(|(_, op)| proto::serialize_operation(&Operation::Buffer(op.clone()))),
 927            );
 928            operations.sort_unstable_by_key(proto::lamport_timestamp_for_operation);
 929            operations
 930        })
 931    }
 932
 933    /// Assign a language to the buffer, returning the buffer.
 934    pub fn with_language(mut self, language: Arc<Language>, cx: &mut Context<Self>) -> Self {
 935        self.set_language(Some(language), cx);
 936        self
 937    }
 938
 939    /// Returns the [`Capability`] of this buffer.
 940    pub fn capability(&self) -> Capability {
 941        self.capability
 942    }
 943
 944    /// Whether this buffer can only be read.
 945    pub fn read_only(&self) -> bool {
 946        self.capability == Capability::ReadOnly
 947    }
 948
 949    /// Builds a [`Buffer`] with the given underlying [`TextBuffer`], diff base, [`File`] and [`Capability`].
 950    pub fn build(buffer: TextBuffer, file: Option<Arc<dyn File>>, capability: Capability) -> Self {
 951        let saved_mtime = file.as_ref().and_then(|file| file.disk_state().mtime());
 952        let snapshot = buffer.snapshot();
 953        let syntax_map = Mutex::new(SyntaxMap::new(&snapshot));
 954        Self {
 955            saved_mtime,
 956            saved_version: buffer.version(),
 957            preview_version: buffer.version(),
 958            reload_task: None,
 959            transaction_depth: 0,
 960            was_dirty_before_starting_transaction: None,
 961            has_unsaved_edits: Cell::new((buffer.version(), false)),
 962            text: buffer,
 963            branch_state: None,
 964            file,
 965            capability,
 966            syntax_map,
 967            reparse: None,
 968            non_text_state_update_count: 0,
 969            sync_parse_timeout: Duration::from_millis(1),
 970            parse_status: async_watch::channel(ParseStatus::Idle),
 971            autoindent_requests: Default::default(),
 972            pending_autoindent: Default::default(),
 973            language: None,
 974            remote_selections: Default::default(),
 975            diagnostics: Default::default(),
 976            diagnostics_timestamp: Default::default(),
 977            completion_triggers: Default::default(),
 978            completion_triggers_per_language_server: Default::default(),
 979            completion_triggers_timestamp: Default::default(),
 980            deferred_ops: OperationQueue::new(),
 981            has_conflict: false,
 982            change_bits: Default::default(),
 983            _subscriptions: Vec::new(),
 984        }
 985    }
 986
 987    pub fn build_snapshot(
 988        text: Rope,
 989        language: Option<Arc<Language>>,
 990        language_registry: Option<Arc<LanguageRegistry>>,
 991        cx: &mut App,
 992    ) -> impl Future<Output = BufferSnapshot> {
 993        let entity_id = cx.reserve_entity::<Self>().entity_id();
 994        let buffer_id = entity_id.as_non_zero_u64().into();
 995        async move {
 996            let text =
 997                TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
 998            let mut syntax = SyntaxMap::new(&text).snapshot();
 999            if let Some(language) = language.clone() {
1000                let text = text.clone();
1001                let language = language.clone();
1002                let language_registry = language_registry.clone();
1003                syntax.reparse(&text, language_registry, language);
1004            }
1005            BufferSnapshot {
1006                text,
1007                syntax,
1008                file: None,
1009                diagnostics: Default::default(),
1010                remote_selections: Default::default(),
1011                language,
1012                non_text_state_update_count: 0,
1013            }
1014        }
1015    }
1016
1017    pub fn build_empty_snapshot(cx: &mut App) -> BufferSnapshot {
1018        let entity_id = cx.reserve_entity::<Self>().entity_id();
1019        let buffer_id = entity_id.as_non_zero_u64().into();
1020        let text =
1021            TextBuffer::new_normalized(0, buffer_id, Default::default(), Rope::new()).snapshot();
1022        let syntax = SyntaxMap::new(&text).snapshot();
1023        BufferSnapshot {
1024            text,
1025            syntax,
1026            file: None,
1027            diagnostics: Default::default(),
1028            remote_selections: Default::default(),
1029            language: None,
1030            non_text_state_update_count: 0,
1031        }
1032    }
1033
1034    #[cfg(any(test, feature = "test-support"))]
1035    pub fn build_snapshot_sync(
1036        text: Rope,
1037        language: Option<Arc<Language>>,
1038        language_registry: Option<Arc<LanguageRegistry>>,
1039        cx: &mut App,
1040    ) -> BufferSnapshot {
1041        let entity_id = cx.reserve_entity::<Self>().entity_id();
1042        let buffer_id = entity_id.as_non_zero_u64().into();
1043        let text = TextBuffer::new_normalized(0, buffer_id, Default::default(), text).snapshot();
1044        let mut syntax = SyntaxMap::new(&text).snapshot();
1045        if let Some(language) = language.clone() {
1046            let text = text.clone();
1047            let language = language.clone();
1048            let language_registry = language_registry.clone();
1049            syntax.reparse(&text, language_registry, language);
1050        }
1051        BufferSnapshot {
1052            text,
1053            syntax,
1054            file: None,
1055            diagnostics: Default::default(),
1056            remote_selections: Default::default(),
1057            language,
1058            non_text_state_update_count: 0,
1059        }
1060    }
1061
1062    /// Retrieve a snapshot of the buffer's current state. This is computationally
1063    /// cheap, and allows reading from the buffer on a background thread.
1064    pub fn snapshot(&self) -> BufferSnapshot {
1065        let text = self.text.snapshot();
1066        let mut syntax_map = self.syntax_map.lock();
1067        syntax_map.interpolate(&text);
1068        let syntax = syntax_map.snapshot();
1069
1070        BufferSnapshot {
1071            text,
1072            syntax,
1073            file: self.file.clone(),
1074            remote_selections: self.remote_selections.clone(),
1075            diagnostics: self.diagnostics.clone(),
1076            language: self.language.clone(),
1077            non_text_state_update_count: self.non_text_state_update_count,
1078        }
1079    }
1080
1081    pub fn branch(&mut self, cx: &mut Context<Self>) -> Entity<Self> {
1082        let this = cx.entity();
1083        cx.new(|cx| {
1084            let mut branch = Self {
1085                branch_state: Some(BufferBranchState {
1086                    base_buffer: this.clone(),
1087                    merged_operations: Default::default(),
1088                }),
1089                language: self.language.clone(),
1090                has_conflict: self.has_conflict,
1091                has_unsaved_edits: Cell::new(self.has_unsaved_edits.get_mut().clone()),
1092                _subscriptions: vec![cx.subscribe(&this, Self::on_base_buffer_event)],
1093                ..Self::build(self.text.branch(), self.file.clone(), self.capability())
1094            };
1095            if let Some(language_registry) = self.language_registry() {
1096                branch.set_language_registry(language_registry);
1097            }
1098
1099            // Reparse the branch buffer so that we get syntax highlighting immediately.
1100            branch.reparse(cx);
1101
1102            branch
1103        })
1104    }
1105
1106    pub fn preview_edits(
1107        &self,
1108        edits: Arc<[(Range<Anchor>, String)]>,
1109        cx: &App,
1110    ) -> Task<EditPreview> {
1111        let registry = self.language_registry();
1112        let language = self.language().cloned();
1113        let old_snapshot = self.text.snapshot();
1114        let mut branch_buffer = self.text.branch();
1115        let mut syntax_snapshot = self.syntax_map.lock().snapshot();
1116        cx.background_spawn(async move {
1117            if !edits.is_empty() {
1118                if let Some(language) = language.clone() {
1119                    syntax_snapshot.reparse(&old_snapshot, registry.clone(), language);
1120                }
1121
1122                branch_buffer.edit(edits.iter().cloned());
1123                let snapshot = branch_buffer.snapshot();
1124                syntax_snapshot.interpolate(&snapshot);
1125
1126                if let Some(language) = language {
1127                    syntax_snapshot.reparse(&snapshot, registry, language);
1128                }
1129            }
1130            EditPreview {
1131                old_snapshot,
1132                applied_edits_snapshot: branch_buffer.snapshot(),
1133                syntax_snapshot,
1134            }
1135        })
1136    }
1137
1138    /// Applies all of the changes in this buffer that intersect any of the
1139    /// given `ranges` to its base buffer.
1140    ///
1141    /// If `ranges` is empty, then all changes will be applied. This buffer must
1142    /// be a branch buffer to call this method.
1143    pub fn merge_into_base(&mut self, ranges: Vec<Range<usize>>, cx: &mut Context<Self>) {
1144        let Some(base_buffer) = self.base_buffer() else {
1145            debug_panic!("not a branch buffer");
1146            return;
1147        };
1148
1149        let mut ranges = if ranges.is_empty() {
1150            &[0..usize::MAX]
1151        } else {
1152            ranges.as_slice()
1153        }
1154        .into_iter()
1155        .peekable();
1156
1157        let mut edits = Vec::new();
1158        for edit in self.edits_since::<usize>(&base_buffer.read(cx).version()) {
1159            let mut is_included = false;
1160            while let Some(range) = ranges.peek() {
1161                if range.end < edit.new.start {
1162                    ranges.next().unwrap();
1163                } else {
1164                    if range.start <= edit.new.end {
1165                        is_included = true;
1166                    }
1167                    break;
1168                }
1169            }
1170
1171            if is_included {
1172                edits.push((
1173                    edit.old.clone(),
1174                    self.text_for_range(edit.new.clone()).collect::<String>(),
1175                ));
1176            }
1177        }
1178
1179        let operation = base_buffer.update(cx, |base_buffer, cx| {
1180            // cx.emit(BufferEvent::DiffBaseChanged);
1181            base_buffer.edit(edits, None, cx)
1182        });
1183
1184        if let Some(operation) = operation {
1185            if let Some(BufferBranchState {
1186                merged_operations, ..
1187            }) = &mut self.branch_state
1188            {
1189                merged_operations.push(operation);
1190            }
1191        }
1192    }
1193
1194    fn on_base_buffer_event(
1195        &mut self,
1196        _: Entity<Buffer>,
1197        event: &BufferEvent,
1198        cx: &mut Context<Self>,
1199    ) {
1200        let BufferEvent::Operation { operation, .. } = event else {
1201            return;
1202        };
1203        let Some(BufferBranchState {
1204            merged_operations, ..
1205        }) = &mut self.branch_state
1206        else {
1207            return;
1208        };
1209
1210        let mut operation_to_undo = None;
1211        if let Operation::Buffer(text::Operation::Edit(operation)) = &operation {
1212            if let Ok(ix) = merged_operations.binary_search(&operation.timestamp) {
1213                merged_operations.remove(ix);
1214                operation_to_undo = Some(operation.timestamp);
1215            }
1216        }
1217
1218        self.apply_ops([operation.clone()], cx);
1219
1220        if let Some(timestamp) = operation_to_undo {
1221            let counts = [(timestamp, u32::MAX)].into_iter().collect();
1222            self.undo_operations(counts, cx);
1223        }
1224    }
1225
1226    #[cfg(test)]
1227    pub(crate) fn as_text_snapshot(&self) -> &text::BufferSnapshot {
1228        &self.text
1229    }
1230
1231    /// Retrieve a snapshot of the buffer's raw text, without any
1232    /// language-related state like the syntax tree or diagnostics.
1233    pub fn text_snapshot(&self) -> text::BufferSnapshot {
1234        self.text.snapshot()
1235    }
1236
1237    /// The file associated with the buffer, if any.
1238    pub fn file(&self) -> Option<&Arc<dyn File>> {
1239        self.file.as_ref()
1240    }
1241
1242    /// The version of the buffer that was last saved or reloaded from disk.
1243    pub fn saved_version(&self) -> &clock::Global {
1244        &self.saved_version
1245    }
1246
1247    /// The mtime of the buffer's file when the buffer was last saved or reloaded from disk.
1248    pub fn saved_mtime(&self) -> Option<MTime> {
1249        self.saved_mtime
1250    }
1251
1252    /// Assign a language to the buffer.
1253    pub fn set_language(&mut self, language: Option<Arc<Language>>, cx: &mut Context<Self>) {
1254        self.non_text_state_update_count += 1;
1255        self.syntax_map.lock().clear(&self.text);
1256        self.language = language;
1257        self.was_changed();
1258        self.reparse(cx);
1259        cx.emit(BufferEvent::LanguageChanged);
1260    }
1261
1262    /// Assign a language registry to the buffer. This allows the buffer to retrieve
1263    /// other languages if parts of the buffer are written in different languages.
1264    pub fn set_language_registry(&self, language_registry: Arc<LanguageRegistry>) {
1265        self.syntax_map
1266            .lock()
1267            .set_language_registry(language_registry);
1268    }
1269
1270    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
1271        self.syntax_map.lock().language_registry()
1272    }
1273
1274    /// Assign the buffer a new [`Capability`].
1275    pub fn set_capability(&mut self, capability: Capability, cx: &mut Context<Self>) {
1276        self.capability = capability;
1277        cx.emit(BufferEvent::CapabilityChanged)
1278    }
1279
1280    /// This method is called to signal that the buffer has been saved.
1281    pub fn did_save(
1282        &mut self,
1283        version: clock::Global,
1284        mtime: Option<MTime>,
1285        cx: &mut Context<Self>,
1286    ) {
1287        self.saved_version = version;
1288        self.has_unsaved_edits
1289            .set((self.saved_version().clone(), false));
1290        self.has_conflict = false;
1291        self.saved_mtime = mtime;
1292        self.was_changed();
1293        cx.emit(BufferEvent::Saved);
1294        cx.notify();
1295    }
1296
1297    /// This method is called to signal that the buffer has been discarded.
1298    pub fn discarded(&self, cx: &mut Context<Self>) {
1299        cx.emit(BufferEvent::Discarded);
1300        cx.notify();
1301    }
1302
1303    /// Reloads the contents of the buffer from disk.
1304    pub fn reload(&mut self, cx: &Context<Self>) -> oneshot::Receiver<Option<Transaction>> {
1305        let (tx, rx) = futures::channel::oneshot::channel();
1306        let prev_version = self.text.version();
1307        self.reload_task = Some(cx.spawn(|this, mut cx| async move {
1308            let Some((new_mtime, new_text)) = this.update(&mut cx, |this, cx| {
1309                let file = this.file.as_ref()?.as_local()?;
1310                Some((file.disk_state().mtime(), file.load(cx)))
1311            })?
1312            else {
1313                return Ok(());
1314            };
1315
1316            let new_text = new_text.await?;
1317            let diff = this
1318                .update(&mut cx, |this, cx| this.diff(new_text.clone(), cx))?
1319                .await;
1320            this.update(&mut cx, |this, cx| {
1321                if this.version() == diff.base_version {
1322                    this.finalize_last_transaction();
1323                    this.apply_diff(diff, cx);
1324                    tx.send(this.finalize_last_transaction().cloned()).ok();
1325                    this.has_conflict = false;
1326                    this.did_reload(this.version(), this.line_ending(), new_mtime, cx);
1327                } else {
1328                    if !diff.edits.is_empty()
1329                        || this
1330                            .edits_since::<usize>(&diff.base_version)
1331                            .next()
1332                            .is_some()
1333                    {
1334                        this.has_conflict = true;
1335                    }
1336
1337                    this.did_reload(prev_version, this.line_ending(), this.saved_mtime, cx);
1338                }
1339
1340                this.reload_task.take();
1341            })
1342        }));
1343        rx
1344    }
1345
1346    /// This method is called to signal that the buffer has been reloaded.
1347    pub fn did_reload(
1348        &mut self,
1349        version: clock::Global,
1350        line_ending: LineEnding,
1351        mtime: Option<MTime>,
1352        cx: &mut Context<Self>,
1353    ) {
1354        self.saved_version = version;
1355        self.has_unsaved_edits
1356            .set((self.saved_version.clone(), false));
1357        self.text.set_line_ending(line_ending);
1358        self.saved_mtime = mtime;
1359        cx.emit(BufferEvent::Reloaded);
1360        cx.notify();
1361    }
1362
1363    /// Updates the [`File`] backing this buffer. This should be called when
1364    /// the file has changed or has been deleted.
1365    pub fn file_updated(&mut self, new_file: Arc<dyn File>, cx: &mut Context<Self>) {
1366        let was_dirty = self.is_dirty();
1367        let mut file_changed = false;
1368
1369        if let Some(old_file) = self.file.as_ref() {
1370            if new_file.path() != old_file.path() {
1371                file_changed = true;
1372            }
1373
1374            let old_state = old_file.disk_state();
1375            let new_state = new_file.disk_state();
1376            if old_state != new_state {
1377                file_changed = true;
1378                if !was_dirty && matches!(new_state, DiskState::Present { .. }) {
1379                    cx.emit(BufferEvent::ReloadNeeded)
1380                }
1381            }
1382        } else {
1383            file_changed = true;
1384        };
1385
1386        self.file = Some(new_file);
1387        if file_changed {
1388            self.was_changed();
1389            self.non_text_state_update_count += 1;
1390            if was_dirty != self.is_dirty() {
1391                cx.emit(BufferEvent::DirtyChanged);
1392            }
1393            cx.emit(BufferEvent::FileHandleChanged);
1394            cx.notify();
1395        }
1396    }
1397
1398    pub fn base_buffer(&self) -> Option<Entity<Self>> {
1399        Some(self.branch_state.as_ref()?.base_buffer.clone())
1400    }
1401
1402    /// Returns the primary [`Language`] assigned to this [`Buffer`].
1403    pub fn language(&self) -> Option<&Arc<Language>> {
1404        self.language.as_ref()
1405    }
1406
1407    /// Returns the [`Language`] at the given location.
1408    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<Arc<Language>> {
1409        let offset = position.to_offset(self);
1410        self.syntax_map
1411            .lock()
1412            .layers_for_range(offset..offset, &self.text, false)
1413            .last()
1414            .map(|info| info.language.clone())
1415            .or_else(|| self.language.clone())
1416    }
1417
1418    /// An integer version number that accounts for all updates besides
1419    /// the buffer's text itself (which is versioned via a version vector).
1420    pub fn non_text_state_update_count(&self) -> usize {
1421        self.non_text_state_update_count
1422    }
1423
1424    /// Whether the buffer is being parsed in the background.
1425    #[cfg(any(test, feature = "test-support"))]
1426    pub fn is_parsing(&self) -> bool {
1427        self.reparse.is_some()
1428    }
1429
1430    /// Indicates whether the buffer contains any regions that may be
1431    /// written in a language that hasn't been loaded yet.
1432    pub fn contains_unknown_injections(&self) -> bool {
1433        self.syntax_map.lock().contains_unknown_injections()
1434    }
1435
1436    #[cfg(test)]
1437    pub fn set_sync_parse_timeout(&mut self, timeout: Duration) {
1438        self.sync_parse_timeout = timeout;
1439    }
1440
1441    /// Called after an edit to synchronize the buffer's main parse tree with
1442    /// the buffer's new underlying state.
1443    ///
1444    /// Locks the syntax map and interpolates the edits since the last reparse
1445    /// into the foreground syntax tree.
1446    ///
1447    /// Then takes a stable snapshot of the syntax map before unlocking it.
1448    /// The snapshot with the interpolated edits is sent to a background thread,
1449    /// where we ask Tree-sitter to perform an incremental parse.
1450    ///
1451    /// Meanwhile, in the foreground, we block the main thread for up to 1ms
1452    /// waiting on the parse to complete. As soon as it completes, we proceed
1453    /// synchronously, unless a 1ms timeout elapses.
1454    ///
1455    /// If we time out waiting on the parse, we spawn a second task waiting
1456    /// until the parse does complete and return with the interpolated tree still
1457    /// in the foreground. When the background parse completes, call back into
1458    /// the main thread and assign the foreground parse state.
1459    ///
1460    /// If the buffer or grammar changed since the start of the background parse,
1461    /// initiate an additional reparse recursively. To avoid concurrent parses
1462    /// for the same buffer, we only initiate a new parse if we are not already
1463    /// parsing in the background.
1464    pub fn reparse(&mut self, cx: &mut Context<Self>) {
1465        if self.reparse.is_some() {
1466            return;
1467        }
1468        let language = if let Some(language) = self.language.clone() {
1469            language
1470        } else {
1471            return;
1472        };
1473
1474        let text = self.text_snapshot();
1475        let parsed_version = self.version();
1476
1477        let mut syntax_map = self.syntax_map.lock();
1478        syntax_map.interpolate(&text);
1479        let language_registry = syntax_map.language_registry();
1480        let mut syntax_snapshot = syntax_map.snapshot();
1481        drop(syntax_map);
1482
1483        let parse_task = cx.background_spawn({
1484            let language = language.clone();
1485            let language_registry = language_registry.clone();
1486            async move {
1487                syntax_snapshot.reparse(&text, language_registry, language);
1488                syntax_snapshot
1489            }
1490        });
1491
1492        self.parse_status.0.send(ParseStatus::Parsing).unwrap();
1493        match cx
1494            .background_executor()
1495            .block_with_timeout(self.sync_parse_timeout, parse_task)
1496        {
1497            Ok(new_syntax_snapshot) => {
1498                self.did_finish_parsing(new_syntax_snapshot, cx);
1499                self.reparse = None;
1500            }
1501            Err(parse_task) => {
1502                self.reparse = Some(cx.spawn(move |this, mut cx| async move {
1503                    let new_syntax_map = parse_task.await;
1504                    this.update(&mut cx, move |this, cx| {
1505                        let grammar_changed =
1506                            this.language.as_ref().map_or(true, |current_language| {
1507                                !Arc::ptr_eq(&language, current_language)
1508                            });
1509                        let language_registry_changed = new_syntax_map
1510                            .contains_unknown_injections()
1511                            && language_registry.map_or(false, |registry| {
1512                                registry.version() != new_syntax_map.language_registry_version()
1513                            });
1514                        let parse_again = language_registry_changed
1515                            || grammar_changed
1516                            || this.version.changed_since(&parsed_version);
1517                        this.did_finish_parsing(new_syntax_map, cx);
1518                        this.reparse = None;
1519                        if parse_again {
1520                            this.reparse(cx);
1521                        }
1522                    })
1523                    .ok();
1524                }));
1525            }
1526        }
1527    }
1528
1529    fn did_finish_parsing(&mut self, syntax_snapshot: SyntaxSnapshot, cx: &mut Context<Self>) {
1530        self.non_text_state_update_count += 1;
1531        self.syntax_map.lock().did_parse(syntax_snapshot);
1532        self.request_autoindent(cx);
1533        self.parse_status.0.send(ParseStatus::Idle).unwrap();
1534        cx.emit(BufferEvent::Reparsed);
1535        cx.notify();
1536    }
1537
1538    pub fn parse_status(&self) -> watch::Receiver<ParseStatus> {
1539        self.parse_status.1.clone()
1540    }
1541
1542    /// Assign to the buffer a set of diagnostics created by a given language server.
1543    pub fn update_diagnostics(
1544        &mut self,
1545        server_id: LanguageServerId,
1546        diagnostics: DiagnosticSet,
1547        cx: &mut Context<Self>,
1548    ) {
1549        let lamport_timestamp = self.text.lamport_clock.tick();
1550        let op = Operation::UpdateDiagnostics {
1551            server_id,
1552            diagnostics: diagnostics.iter().cloned().collect(),
1553            lamport_timestamp,
1554        };
1555        self.apply_diagnostic_update(server_id, diagnostics, lamport_timestamp, cx);
1556        self.send_operation(op, true, cx);
1557    }
1558
1559    fn request_autoindent(&mut self, cx: &mut Context<Self>) {
1560        if let Some(indent_sizes) = self.compute_autoindents() {
1561            let indent_sizes = cx.background_spawn(indent_sizes);
1562            match cx
1563                .background_executor()
1564                .block_with_timeout(Duration::from_micros(500), indent_sizes)
1565            {
1566                Ok(indent_sizes) => self.apply_autoindents(indent_sizes, cx),
1567                Err(indent_sizes) => {
1568                    self.pending_autoindent = Some(cx.spawn(|this, mut cx| async move {
1569                        let indent_sizes = indent_sizes.await;
1570                        this.update(&mut cx, |this, cx| {
1571                            this.apply_autoindents(indent_sizes, cx);
1572                        })
1573                        .ok();
1574                    }));
1575                }
1576            }
1577        } else {
1578            self.autoindent_requests.clear();
1579        }
1580    }
1581
1582    fn compute_autoindents(&self) -> Option<impl Future<Output = BTreeMap<u32, IndentSize>>> {
1583        let max_rows_between_yields = 100;
1584        let snapshot = self.snapshot();
1585        if snapshot.syntax.is_empty() || self.autoindent_requests.is_empty() {
1586            return None;
1587        }
1588
1589        let autoindent_requests = self.autoindent_requests.clone();
1590        Some(async move {
1591            let mut indent_sizes = BTreeMap::<u32, (IndentSize, bool)>::new();
1592            for request in autoindent_requests {
1593                // Resolve each edited range to its row in the current buffer and in the
1594                // buffer before this batch of edits.
1595                let mut row_ranges = Vec::new();
1596                let mut old_to_new_rows = BTreeMap::new();
1597                let mut language_indent_sizes_by_new_row = Vec::new();
1598                for entry in &request.entries {
1599                    let position = entry.range.start;
1600                    let new_row = position.to_point(&snapshot).row;
1601                    let new_end_row = entry.range.end.to_point(&snapshot).row + 1;
1602                    language_indent_sizes_by_new_row.push((new_row, entry.indent_size));
1603
1604                    if !entry.first_line_is_new {
1605                        let old_row = position.to_point(&request.before_edit).row;
1606                        old_to_new_rows.insert(old_row, new_row);
1607                    }
1608                    row_ranges.push((new_row..new_end_row, entry.original_indent_column));
1609                }
1610
1611                // Build a map containing the suggested indentation for each of the edited lines
1612                // with respect to the state of the buffer before these edits. This map is keyed
1613                // by the rows for these lines in the current state of the buffer.
1614                let mut old_suggestions = BTreeMap::<u32, (IndentSize, bool)>::default();
1615                let old_edited_ranges =
1616                    contiguous_ranges(old_to_new_rows.keys().copied(), max_rows_between_yields);
1617                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1618                let mut language_indent_size = IndentSize::default();
1619                for old_edited_range in old_edited_ranges {
1620                    let suggestions = request
1621                        .before_edit
1622                        .suggest_autoindents(old_edited_range.clone())
1623                        .into_iter()
1624                        .flatten();
1625                    for (old_row, suggestion) in old_edited_range.zip(suggestions) {
1626                        if let Some(suggestion) = suggestion {
1627                            let new_row = *old_to_new_rows.get(&old_row).unwrap();
1628
1629                            // Find the indent size based on the language for this row.
1630                            while let Some((row, size)) = language_indent_sizes.peek() {
1631                                if *row > new_row {
1632                                    break;
1633                                }
1634                                language_indent_size = *size;
1635                                language_indent_sizes.next();
1636                            }
1637
1638                            let suggested_indent = old_to_new_rows
1639                                .get(&suggestion.basis_row)
1640                                .and_then(|from_row| {
1641                                    Some(old_suggestions.get(from_row).copied()?.0)
1642                                })
1643                                .unwrap_or_else(|| {
1644                                    request
1645                                        .before_edit
1646                                        .indent_size_for_line(suggestion.basis_row)
1647                                })
1648                                .with_delta(suggestion.delta, language_indent_size);
1649                            old_suggestions
1650                                .insert(new_row, (suggested_indent, suggestion.within_error));
1651                        }
1652                    }
1653                    yield_now().await;
1654                }
1655
1656                // Compute new suggestions for each line, but only include them in the result
1657                // if they differ from the old suggestion for that line.
1658                let mut language_indent_sizes = language_indent_sizes_by_new_row.iter().peekable();
1659                let mut language_indent_size = IndentSize::default();
1660                for (row_range, original_indent_column) in row_ranges {
1661                    let new_edited_row_range = if request.is_block_mode {
1662                        row_range.start..row_range.start + 1
1663                    } else {
1664                        row_range.clone()
1665                    };
1666
1667                    let suggestions = snapshot
1668                        .suggest_autoindents(new_edited_row_range.clone())
1669                        .into_iter()
1670                        .flatten();
1671                    for (new_row, suggestion) in new_edited_row_range.zip(suggestions) {
1672                        if let Some(suggestion) = suggestion {
1673                            // Find the indent size based on the language for this row.
1674                            while let Some((row, size)) = language_indent_sizes.peek() {
1675                                if *row > new_row {
1676                                    break;
1677                                }
1678                                language_indent_size = *size;
1679                                language_indent_sizes.next();
1680                            }
1681
1682                            let suggested_indent = indent_sizes
1683                                .get(&suggestion.basis_row)
1684                                .copied()
1685                                .map(|e| e.0)
1686                                .unwrap_or_else(|| {
1687                                    snapshot.indent_size_for_line(suggestion.basis_row)
1688                                })
1689                                .with_delta(suggestion.delta, language_indent_size);
1690
1691                            if old_suggestions.get(&new_row).map_or(
1692                                true,
1693                                |(old_indentation, was_within_error)| {
1694                                    suggested_indent != *old_indentation
1695                                        && (!suggestion.within_error || *was_within_error)
1696                                },
1697                            ) {
1698                                indent_sizes.insert(
1699                                    new_row,
1700                                    (suggested_indent, request.ignore_empty_lines),
1701                                );
1702                            }
1703                        }
1704                    }
1705
1706                    if let (true, Some(original_indent_column)) =
1707                        (request.is_block_mode, original_indent_column)
1708                    {
1709                        let new_indent =
1710                            if let Some((indent, _)) = indent_sizes.get(&row_range.start) {
1711                                *indent
1712                            } else {
1713                                snapshot.indent_size_for_line(row_range.start)
1714                            };
1715                        let delta = new_indent.len as i64 - original_indent_column as i64;
1716                        if delta != 0 {
1717                            for row in row_range.skip(1) {
1718                                indent_sizes.entry(row).or_insert_with(|| {
1719                                    let mut size = snapshot.indent_size_for_line(row);
1720                                    if size.kind == new_indent.kind {
1721                                        match delta.cmp(&0) {
1722                                            Ordering::Greater => size.len += delta as u32,
1723                                            Ordering::Less => {
1724                                                size.len = size.len.saturating_sub(-delta as u32)
1725                                            }
1726                                            Ordering::Equal => {}
1727                                        }
1728                                    }
1729                                    (size, request.ignore_empty_lines)
1730                                });
1731                            }
1732                        }
1733                    }
1734
1735                    yield_now().await;
1736                }
1737            }
1738
1739            indent_sizes
1740                .into_iter()
1741                .filter_map(|(row, (indent, ignore_empty_lines))| {
1742                    if ignore_empty_lines && snapshot.line_len(row) == 0 {
1743                        None
1744                    } else {
1745                        Some((row, indent))
1746                    }
1747                })
1748                .collect()
1749        })
1750    }
1751
1752    fn apply_autoindents(
1753        &mut self,
1754        indent_sizes: BTreeMap<u32, IndentSize>,
1755        cx: &mut Context<Self>,
1756    ) {
1757        self.autoindent_requests.clear();
1758
1759        let edits: Vec<_> = indent_sizes
1760            .into_iter()
1761            .filter_map(|(row, indent_size)| {
1762                let current_size = indent_size_for_line(self, row);
1763                Self::edit_for_indent_size_adjustment(row, current_size, indent_size)
1764            })
1765            .collect();
1766
1767        let preserve_preview = self.preserve_preview();
1768        self.edit(edits, None, cx);
1769        if preserve_preview {
1770            self.refresh_preview();
1771        }
1772    }
1773
1774    /// Create a minimal edit that will cause the given row to be indented
1775    /// with the given size. After applying this edit, the length of the line
1776    /// will always be at least `new_size.len`.
1777    pub fn edit_for_indent_size_adjustment(
1778        row: u32,
1779        current_size: IndentSize,
1780        new_size: IndentSize,
1781    ) -> Option<(Range<Point>, String)> {
1782        if new_size.kind == current_size.kind {
1783            match new_size.len.cmp(&current_size.len) {
1784                Ordering::Greater => {
1785                    let point = Point::new(row, 0);
1786                    Some((
1787                        point..point,
1788                        iter::repeat(new_size.char())
1789                            .take((new_size.len - current_size.len) as usize)
1790                            .collect::<String>(),
1791                    ))
1792                }
1793
1794                Ordering::Less => Some((
1795                    Point::new(row, 0)..Point::new(row, current_size.len - new_size.len),
1796                    String::new(),
1797                )),
1798
1799                Ordering::Equal => None,
1800            }
1801        } else {
1802            Some((
1803                Point::new(row, 0)..Point::new(row, current_size.len),
1804                iter::repeat(new_size.char())
1805                    .take(new_size.len as usize)
1806                    .collect::<String>(),
1807            ))
1808        }
1809    }
1810
1811    /// Spawns a background task that asynchronously computes a `Diff` between the buffer's text
1812    /// and the given new text.
1813    pub fn diff(&self, mut new_text: String, cx: &App) -> Task<Diff> {
1814        let old_text = self.as_rope().clone();
1815        let base_version = self.version();
1816        cx.background_executor()
1817            .spawn_labeled(*BUFFER_DIFF_TASK, async move {
1818                let old_text = old_text.to_string();
1819                let line_ending = LineEnding::detect(&new_text);
1820                LineEnding::normalize(&mut new_text);
1821                let edits = text_diff(&old_text, &new_text);
1822                Diff {
1823                    base_version,
1824                    line_ending,
1825                    edits,
1826                }
1827            })
1828    }
1829
1830    /// Spawns a background task that searches the buffer for any whitespace
1831    /// at the ends of a lines, and returns a `Diff` that removes that whitespace.
1832    pub fn remove_trailing_whitespace(&self, cx: &App) -> Task<Diff> {
1833        let old_text = self.as_rope().clone();
1834        let line_ending = self.line_ending();
1835        let base_version = self.version();
1836        cx.background_spawn(async move {
1837            let ranges = trailing_whitespace_ranges(&old_text);
1838            let empty = Arc::<str>::from("");
1839            Diff {
1840                base_version,
1841                line_ending,
1842                edits: ranges
1843                    .into_iter()
1844                    .map(|range| (range, empty.clone()))
1845                    .collect(),
1846            }
1847        })
1848    }
1849
1850    /// Ensures that the buffer ends with a single newline character, and
1851    /// no other whitespace.
1852    pub fn ensure_final_newline(&mut self, cx: &mut Context<Self>) {
1853        let len = self.len();
1854        let mut offset = len;
1855        for chunk in self.as_rope().reversed_chunks_in_range(0..len) {
1856            let non_whitespace_len = chunk
1857                .trim_end_matches(|c: char| c.is_ascii_whitespace())
1858                .len();
1859            offset -= chunk.len();
1860            offset += non_whitespace_len;
1861            if non_whitespace_len != 0 {
1862                if offset == len - 1 && chunk.get(non_whitespace_len..) == Some("\n") {
1863                    return;
1864                }
1865                break;
1866            }
1867        }
1868        self.edit([(offset..len, "\n")], None, cx);
1869    }
1870
1871    /// Applies a diff to the buffer. If the buffer has changed since the given diff was
1872    /// calculated, then adjust the diff to account for those changes, and discard any
1873    /// parts of the diff that conflict with those changes.
1874    pub fn apply_diff(&mut self, diff: Diff, cx: &mut Context<Self>) -> Option<TransactionId> {
1875        // Check for any edits to the buffer that have occurred since this diff
1876        // was computed.
1877        let snapshot = self.snapshot();
1878        let mut edits_since = snapshot.edits_since::<usize>(&diff.base_version).peekable();
1879        let mut delta = 0;
1880        let adjusted_edits = diff.edits.into_iter().filter_map(|(range, new_text)| {
1881            while let Some(edit_since) = edits_since.peek() {
1882                // If the edit occurs after a diff hunk, then it does not
1883                // affect that hunk.
1884                if edit_since.old.start > range.end {
1885                    break;
1886                }
1887                // If the edit precedes the diff hunk, then adjust the hunk
1888                // to reflect the edit.
1889                else if edit_since.old.end < range.start {
1890                    delta += edit_since.new_len() as i64 - edit_since.old_len() as i64;
1891                    edits_since.next();
1892                }
1893                // If the edit intersects a diff hunk, then discard that hunk.
1894                else {
1895                    return None;
1896                }
1897            }
1898
1899            let start = (range.start as i64 + delta) as usize;
1900            let end = (range.end as i64 + delta) as usize;
1901            Some((start..end, new_text))
1902        });
1903
1904        self.start_transaction();
1905        self.text.set_line_ending(diff.line_ending);
1906        self.edit(adjusted_edits, None, cx);
1907        self.end_transaction(cx)
1908    }
1909
1910    fn has_unsaved_edits(&self) -> bool {
1911        let (last_version, has_unsaved_edits) = self.has_unsaved_edits.take();
1912
1913        if last_version == self.version {
1914            self.has_unsaved_edits
1915                .set((last_version, has_unsaved_edits));
1916            return has_unsaved_edits;
1917        }
1918
1919        let has_edits = self.has_edits_since(&self.saved_version);
1920        self.has_unsaved_edits
1921            .set((self.version.clone(), has_edits));
1922        has_edits
1923    }
1924
1925    /// Checks if the buffer has unsaved changes.
1926    pub fn is_dirty(&self) -> bool {
1927        if self.capability == Capability::ReadOnly {
1928            return false;
1929        }
1930        if self.has_conflict || self.has_unsaved_edits() {
1931            return true;
1932        }
1933        match self.file.as_ref().map(|f| f.disk_state()) {
1934            Some(DiskState::New) => !self.is_empty(),
1935            Some(DiskState::Deleted) => true,
1936            _ => false,
1937        }
1938    }
1939
1940    /// Checks if the buffer and its file have both changed since the buffer
1941    /// was last saved or reloaded.
1942    pub fn has_conflict(&self) -> bool {
1943        if self.has_conflict {
1944            return true;
1945        }
1946        let Some(file) = self.file.as_ref() else {
1947            return false;
1948        };
1949        match file.disk_state() {
1950            DiskState::New => false,
1951            DiskState::Present { mtime } => match self.saved_mtime {
1952                Some(saved_mtime) => {
1953                    mtime.bad_is_greater_than(saved_mtime) && self.has_unsaved_edits()
1954                }
1955                None => true,
1956            },
1957            DiskState::Deleted => true,
1958        }
1959    }
1960
1961    /// Gets a [`Subscription`] that tracks all of the changes to the buffer's text.
1962    pub fn subscribe(&mut self) -> Subscription {
1963        self.text.subscribe()
1964    }
1965
1966    /// Adds a bit to the list of bits that are set when the buffer's text changes.
1967    ///
1968    /// This allows downstream code to check if the buffer's text has changed without
1969    /// waiting for an effect cycle, which would be required if using eents.
1970    pub fn record_changes(&mut self, bit: rc::Weak<Cell<bool>>) {
1971        self.change_bits.push(bit);
1972    }
1973
1974    fn was_changed(&mut self) {
1975        self.change_bits.retain(|change_bit| {
1976            change_bit.upgrade().map_or(false, |bit| {
1977                bit.replace(true);
1978                true
1979            })
1980        });
1981    }
1982
1983    /// Starts a transaction, if one is not already in-progress. When undoing or
1984    /// redoing edits, all of the edits performed within a transaction are undone
1985    /// or redone together.
1986    pub fn start_transaction(&mut self) -> Option<TransactionId> {
1987        self.start_transaction_at(Instant::now())
1988    }
1989
1990    /// Starts a transaction, providing the current time. Subsequent transactions
1991    /// that occur within a short period of time will be grouped together. This
1992    /// is controlled by the buffer's undo grouping duration.
1993    pub fn start_transaction_at(&mut self, now: Instant) -> Option<TransactionId> {
1994        self.transaction_depth += 1;
1995        if self.was_dirty_before_starting_transaction.is_none() {
1996            self.was_dirty_before_starting_transaction = Some(self.is_dirty());
1997        }
1998        self.text.start_transaction_at(now)
1999    }
2000
2001    /// Terminates the current transaction, if this is the outermost transaction.
2002    pub fn end_transaction(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2003        self.end_transaction_at(Instant::now(), cx)
2004    }
2005
2006    /// Terminates the current transaction, providing the current time. Subsequent transactions
2007    /// that occur within a short period of time will be grouped together. This
2008    /// is controlled by the buffer's undo grouping duration.
2009    pub fn end_transaction_at(
2010        &mut self,
2011        now: Instant,
2012        cx: &mut Context<Self>,
2013    ) -> Option<TransactionId> {
2014        assert!(self.transaction_depth > 0);
2015        self.transaction_depth -= 1;
2016        let was_dirty = if self.transaction_depth == 0 {
2017            self.was_dirty_before_starting_transaction.take().unwrap()
2018        } else {
2019            false
2020        };
2021        if let Some((transaction_id, start_version)) = self.text.end_transaction_at(now) {
2022            self.did_edit(&start_version, was_dirty, cx);
2023            Some(transaction_id)
2024        } else {
2025            None
2026        }
2027    }
2028
2029    /// Manually add a transaction to the buffer's undo history.
2030    pub fn push_transaction(&mut self, transaction: Transaction, now: Instant) {
2031        self.text.push_transaction(transaction, now);
2032    }
2033
2034    /// Prevent the last transaction from being grouped with any subsequent transactions,
2035    /// even if they occur with the buffer's undo grouping duration.
2036    pub fn finalize_last_transaction(&mut self) -> Option<&Transaction> {
2037        self.text.finalize_last_transaction()
2038    }
2039
2040    /// Manually group all changes since a given transaction.
2041    pub fn group_until_transaction(&mut self, transaction_id: TransactionId) {
2042        self.text.group_until_transaction(transaction_id);
2043    }
2044
2045    /// Manually remove a transaction from the buffer's undo history
2046    pub fn forget_transaction(&mut self, transaction_id: TransactionId) {
2047        self.text.forget_transaction(transaction_id);
2048    }
2049
2050    /// Manually merge two adjacent transactions in the buffer's undo history.
2051    pub fn merge_transactions(&mut self, transaction: TransactionId, destination: TransactionId) {
2052        self.text.merge_transactions(transaction, destination);
2053    }
2054
2055    /// Waits for the buffer to receive operations with the given timestamps.
2056    pub fn wait_for_edits(
2057        &mut self,
2058        edit_ids: impl IntoIterator<Item = clock::Lamport>,
2059    ) -> impl Future<Output = Result<()>> {
2060        self.text.wait_for_edits(edit_ids)
2061    }
2062
2063    /// Waits for the buffer to receive the operations necessary for resolving the given anchors.
2064    pub fn wait_for_anchors(
2065        &mut self,
2066        anchors: impl IntoIterator<Item = Anchor>,
2067    ) -> impl 'static + Future<Output = Result<()>> {
2068        self.text.wait_for_anchors(anchors)
2069    }
2070
2071    /// Waits for the buffer to receive operations up to the given version.
2072    pub fn wait_for_version(&mut self, version: clock::Global) -> impl Future<Output = Result<()>> {
2073        self.text.wait_for_version(version)
2074    }
2075
2076    /// Forces all futures returned by [`Buffer::wait_for_version`], [`Buffer::wait_for_edits`], or
2077    /// [`Buffer::wait_for_version`] to resolve with an error.
2078    pub fn give_up_waiting(&mut self) {
2079        self.text.give_up_waiting();
2080    }
2081
2082    /// Stores a set of selections that should be broadcasted to all of the buffer's replicas.
2083    pub fn set_active_selections(
2084        &mut self,
2085        selections: Arc<[Selection<Anchor>]>,
2086        line_mode: bool,
2087        cursor_shape: CursorShape,
2088        cx: &mut Context<Self>,
2089    ) {
2090        let lamport_timestamp = self.text.lamport_clock.tick();
2091        self.remote_selections.insert(
2092            self.text.replica_id(),
2093            SelectionSet {
2094                selections: selections.clone(),
2095                lamport_timestamp,
2096                line_mode,
2097                cursor_shape,
2098            },
2099        );
2100        self.send_operation(
2101            Operation::UpdateSelections {
2102                selections,
2103                line_mode,
2104                lamport_timestamp,
2105                cursor_shape,
2106            },
2107            true,
2108            cx,
2109        );
2110        self.non_text_state_update_count += 1;
2111        cx.notify();
2112    }
2113
2114    /// Clears the selections, so that other replicas of the buffer do not see any selections for
2115    /// this replica.
2116    pub fn remove_active_selections(&mut self, cx: &mut Context<Self>) {
2117        if self
2118            .remote_selections
2119            .get(&self.text.replica_id())
2120            .map_or(true, |set| !set.selections.is_empty())
2121        {
2122            self.set_active_selections(Arc::default(), false, Default::default(), cx);
2123        }
2124    }
2125
2126    /// Replaces the buffer's entire text.
2127    pub fn set_text<T>(&mut self, text: T, cx: &mut Context<Self>) -> Option<clock::Lamport>
2128    where
2129        T: Into<Arc<str>>,
2130    {
2131        self.autoindent_requests.clear();
2132        self.edit([(0..self.len(), text)], None, cx)
2133    }
2134
2135    /// Applies the given edits to the buffer. Each edit is specified as a range of text to
2136    /// delete, and a string of text to insert at that location.
2137    ///
2138    /// If an [`AutoindentMode`] is provided, then the buffer will enqueue an auto-indent
2139    /// request for the edited ranges, which will be processed when the buffer finishes
2140    /// parsing.
2141    ///
2142    /// Parsing takes place at the end of a transaction, and may compute synchronously
2143    /// or asynchronously, depending on the changes.
2144    pub fn edit<I, S, T>(
2145        &mut self,
2146        edits_iter: I,
2147        autoindent_mode: Option<AutoindentMode>,
2148        cx: &mut Context<Self>,
2149    ) -> Option<clock::Lamport>
2150    where
2151        I: IntoIterator<Item = (Range<S>, T)>,
2152        S: ToOffset,
2153        T: Into<Arc<str>>,
2154    {
2155        // Skip invalid edits and coalesce contiguous ones.
2156        let mut edits: Vec<(Range<usize>, Arc<str>)> = Vec::new();
2157        for (range, new_text) in edits_iter {
2158            let mut range = range.start.to_offset(self)..range.end.to_offset(self);
2159            if range.start > range.end {
2160                mem::swap(&mut range.start, &mut range.end);
2161            }
2162            let new_text = new_text.into();
2163            if !new_text.is_empty() || !range.is_empty() {
2164                if let Some((prev_range, prev_text)) = edits.last_mut() {
2165                    if prev_range.end >= range.start {
2166                        prev_range.end = cmp::max(prev_range.end, range.end);
2167                        *prev_text = format!("{prev_text}{new_text}").into();
2168                    } else {
2169                        edits.push((range, new_text));
2170                    }
2171                } else {
2172                    edits.push((range, new_text));
2173                }
2174            }
2175        }
2176        if edits.is_empty() {
2177            return None;
2178        }
2179
2180        self.start_transaction();
2181        self.pending_autoindent.take();
2182        let autoindent_request = autoindent_mode
2183            .and_then(|mode| self.language.as_ref().map(|_| (self.snapshot(), mode)));
2184
2185        let edit_operation = self.text.edit(edits.iter().cloned());
2186        let edit_id = edit_operation.timestamp();
2187
2188        if let Some((before_edit, mode)) = autoindent_request {
2189            let mut delta = 0isize;
2190            let entries = edits
2191                .into_iter()
2192                .enumerate()
2193                .zip(&edit_operation.as_edit().unwrap().new_text)
2194                .map(|((ix, (range, _)), new_text)| {
2195                    let new_text_length = new_text.len();
2196                    let old_start = range.start.to_point(&before_edit);
2197                    let new_start = (delta + range.start as isize) as usize;
2198                    let range_len = range.end - range.start;
2199                    delta += new_text_length as isize - range_len as isize;
2200
2201                    // Decide what range of the insertion to auto-indent, and whether
2202                    // the first line of the insertion should be considered a newly-inserted line
2203                    // or an edit to an existing line.
2204                    let mut range_of_insertion_to_indent = 0..new_text_length;
2205                    let mut first_line_is_new = true;
2206
2207                    let old_line_start = before_edit.indent_size_for_line(old_start.row).len;
2208                    let old_line_end = before_edit.line_len(old_start.row);
2209
2210                    if old_start.column > old_line_start {
2211                        first_line_is_new = false;
2212                    }
2213
2214                    if !new_text.contains('\n')
2215                        && (old_start.column + (range_len as u32) < old_line_end
2216                            || old_line_end == old_line_start)
2217                    {
2218                        first_line_is_new = false;
2219                    }
2220
2221                    // When inserting text starting with a newline, avoid auto-indenting the
2222                    // previous line.
2223                    if new_text.starts_with('\n') {
2224                        range_of_insertion_to_indent.start += 1;
2225                        first_line_is_new = true;
2226                    }
2227
2228                    let mut original_indent_column = None;
2229                    if let AutoindentMode::Block {
2230                        original_indent_columns,
2231                    } = &mode
2232                    {
2233                        original_indent_column = Some(
2234                            original_indent_columns
2235                                .get(ix)
2236                                .copied()
2237                                .flatten()
2238                                .unwrap_or_else(|| {
2239                                    indent_size_for_text(
2240                                        new_text[range_of_insertion_to_indent.clone()].chars(),
2241                                    )
2242                                    .len
2243                                }),
2244                        );
2245
2246                        // Avoid auto-indenting the line after the edit.
2247                        if new_text[range_of_insertion_to_indent.clone()].ends_with('\n') {
2248                            range_of_insertion_to_indent.end -= 1;
2249                        }
2250                    }
2251
2252                    AutoindentRequestEntry {
2253                        first_line_is_new,
2254                        original_indent_column,
2255                        indent_size: before_edit.language_indent_size_at(range.start, cx),
2256                        range: self.anchor_before(new_start + range_of_insertion_to_indent.start)
2257                            ..self.anchor_after(new_start + range_of_insertion_to_indent.end),
2258                    }
2259                })
2260                .collect();
2261
2262            self.autoindent_requests.push(Arc::new(AutoindentRequest {
2263                before_edit,
2264                entries,
2265                is_block_mode: matches!(mode, AutoindentMode::Block { .. }),
2266                ignore_empty_lines: false,
2267            }));
2268        }
2269
2270        self.end_transaction(cx);
2271        self.send_operation(Operation::Buffer(edit_operation), true, cx);
2272        Some(edit_id)
2273    }
2274
2275    fn did_edit(&mut self, old_version: &clock::Global, was_dirty: bool, cx: &mut Context<Self>) {
2276        if self.edits_since::<usize>(old_version).next().is_none() {
2277            return;
2278        }
2279
2280        self.reparse(cx);
2281
2282        cx.emit(BufferEvent::Edited);
2283        if was_dirty != self.is_dirty() {
2284            cx.emit(BufferEvent::DirtyChanged);
2285        }
2286        cx.notify();
2287    }
2288
2289    pub fn autoindent_ranges<I, T>(&mut self, ranges: I, cx: &mut Context<Self>)
2290    where
2291        I: IntoIterator<Item = Range<T>>,
2292        T: ToOffset + Copy,
2293    {
2294        let before_edit = self.snapshot();
2295        let entries = ranges
2296            .into_iter()
2297            .map(|range| AutoindentRequestEntry {
2298                range: before_edit.anchor_before(range.start)..before_edit.anchor_after(range.end),
2299                first_line_is_new: true,
2300                indent_size: before_edit.language_indent_size_at(range.start, cx),
2301                original_indent_column: None,
2302            })
2303            .collect();
2304        self.autoindent_requests.push(Arc::new(AutoindentRequest {
2305            before_edit,
2306            entries,
2307            is_block_mode: false,
2308            ignore_empty_lines: true,
2309        }));
2310        self.request_autoindent(cx);
2311    }
2312
2313    // Inserts newlines at the given position to create an empty line, returning the start of the new line.
2314    // You can also request the insertion of empty lines above and below the line starting at the returned point.
2315    pub fn insert_empty_line(
2316        &mut self,
2317        position: impl ToPoint,
2318        space_above: bool,
2319        space_below: bool,
2320        cx: &mut Context<Self>,
2321    ) -> Point {
2322        let mut position = position.to_point(self);
2323
2324        self.start_transaction();
2325
2326        self.edit(
2327            [(position..position, "\n")],
2328            Some(AutoindentMode::EachLine),
2329            cx,
2330        );
2331
2332        if position.column > 0 {
2333            position += Point::new(1, 0);
2334        }
2335
2336        if !self.is_line_blank(position.row) {
2337            self.edit(
2338                [(position..position, "\n")],
2339                Some(AutoindentMode::EachLine),
2340                cx,
2341            );
2342        }
2343
2344        if space_above && position.row > 0 && !self.is_line_blank(position.row - 1) {
2345            self.edit(
2346                [(position..position, "\n")],
2347                Some(AutoindentMode::EachLine),
2348                cx,
2349            );
2350            position.row += 1;
2351        }
2352
2353        if space_below
2354            && (position.row == self.max_point().row || !self.is_line_blank(position.row + 1))
2355        {
2356            self.edit(
2357                [(position..position, "\n")],
2358                Some(AutoindentMode::EachLine),
2359                cx,
2360            );
2361        }
2362
2363        self.end_transaction(cx);
2364
2365        position
2366    }
2367
2368    /// Applies the given remote operations to the buffer.
2369    pub fn apply_ops<I: IntoIterator<Item = Operation>>(&mut self, ops: I, cx: &mut Context<Self>) {
2370        self.pending_autoindent.take();
2371        let was_dirty = self.is_dirty();
2372        let old_version = self.version.clone();
2373        let mut deferred_ops = Vec::new();
2374        let buffer_ops = ops
2375            .into_iter()
2376            .filter_map(|op| match op {
2377                Operation::Buffer(op) => Some(op),
2378                _ => {
2379                    if self.can_apply_op(&op) {
2380                        self.apply_op(op, cx);
2381                    } else {
2382                        deferred_ops.push(op);
2383                    }
2384                    None
2385                }
2386            })
2387            .collect::<Vec<_>>();
2388        for operation in buffer_ops.iter() {
2389            self.send_operation(Operation::Buffer(operation.clone()), false, cx);
2390        }
2391        self.text.apply_ops(buffer_ops);
2392        self.deferred_ops.insert(deferred_ops);
2393        self.was_changed();
2394        self.flush_deferred_ops(cx);
2395        self.did_edit(&old_version, was_dirty, cx);
2396        // Notify independently of whether the buffer was edited as the operations could include a
2397        // selection update.
2398        cx.notify();
2399    }
2400
2401    fn flush_deferred_ops(&mut self, cx: &mut Context<Self>) {
2402        let mut deferred_ops = Vec::new();
2403        for op in self.deferred_ops.drain().iter().cloned() {
2404            if self.can_apply_op(&op) {
2405                self.apply_op(op, cx);
2406            } else {
2407                deferred_ops.push(op);
2408            }
2409        }
2410        self.deferred_ops.insert(deferred_ops);
2411    }
2412
2413    pub fn has_deferred_ops(&self) -> bool {
2414        !self.deferred_ops.is_empty() || self.text.has_deferred_ops()
2415    }
2416
2417    fn can_apply_op(&self, operation: &Operation) -> bool {
2418        match operation {
2419            Operation::Buffer(_) => {
2420                unreachable!("buffer operations should never be applied at this layer")
2421            }
2422            Operation::UpdateDiagnostics {
2423                diagnostics: diagnostic_set,
2424                ..
2425            } => diagnostic_set.iter().all(|diagnostic| {
2426                self.text.can_resolve(&diagnostic.range.start)
2427                    && self.text.can_resolve(&diagnostic.range.end)
2428            }),
2429            Operation::UpdateSelections { selections, .. } => selections
2430                .iter()
2431                .all(|s| self.can_resolve(&s.start) && self.can_resolve(&s.end)),
2432            Operation::UpdateCompletionTriggers { .. } => true,
2433        }
2434    }
2435
2436    fn apply_op(&mut self, operation: Operation, cx: &mut Context<Self>) {
2437        match operation {
2438            Operation::Buffer(_) => {
2439                unreachable!("buffer operations should never be applied at this layer")
2440            }
2441            Operation::UpdateDiagnostics {
2442                server_id,
2443                diagnostics: diagnostic_set,
2444                lamport_timestamp,
2445            } => {
2446                let snapshot = self.snapshot();
2447                self.apply_diagnostic_update(
2448                    server_id,
2449                    DiagnosticSet::from_sorted_entries(diagnostic_set.iter().cloned(), &snapshot),
2450                    lamport_timestamp,
2451                    cx,
2452                );
2453            }
2454            Operation::UpdateSelections {
2455                selections,
2456                lamport_timestamp,
2457                line_mode,
2458                cursor_shape,
2459            } => {
2460                if let Some(set) = self.remote_selections.get(&lamport_timestamp.replica_id) {
2461                    if set.lamport_timestamp > lamport_timestamp {
2462                        return;
2463                    }
2464                }
2465
2466                self.remote_selections.insert(
2467                    lamport_timestamp.replica_id,
2468                    SelectionSet {
2469                        selections,
2470                        lamport_timestamp,
2471                        line_mode,
2472                        cursor_shape,
2473                    },
2474                );
2475                self.text.lamport_clock.observe(lamport_timestamp);
2476                self.non_text_state_update_count += 1;
2477            }
2478            Operation::UpdateCompletionTriggers {
2479                triggers,
2480                lamport_timestamp,
2481                server_id,
2482            } => {
2483                if triggers.is_empty() {
2484                    self.completion_triggers_per_language_server
2485                        .remove(&server_id);
2486                    self.completion_triggers = self
2487                        .completion_triggers_per_language_server
2488                        .values()
2489                        .flat_map(|triggers| triggers.into_iter().cloned())
2490                        .collect();
2491                } else {
2492                    self.completion_triggers_per_language_server
2493                        .insert(server_id, triggers.iter().cloned().collect());
2494                    self.completion_triggers.extend(triggers);
2495                }
2496                self.text.lamport_clock.observe(lamport_timestamp);
2497            }
2498        }
2499    }
2500
2501    fn apply_diagnostic_update(
2502        &mut self,
2503        server_id: LanguageServerId,
2504        diagnostics: DiagnosticSet,
2505        lamport_timestamp: clock::Lamport,
2506        cx: &mut Context<Self>,
2507    ) {
2508        if lamport_timestamp > self.diagnostics_timestamp {
2509            let ix = self.diagnostics.binary_search_by_key(&server_id, |e| e.0);
2510            if diagnostics.is_empty() {
2511                if let Ok(ix) = ix {
2512                    self.diagnostics.remove(ix);
2513                }
2514            } else {
2515                match ix {
2516                    Err(ix) => self.diagnostics.insert(ix, (server_id, diagnostics)),
2517                    Ok(ix) => self.diagnostics[ix].1 = diagnostics,
2518                };
2519            }
2520            self.diagnostics_timestamp = lamport_timestamp;
2521            self.non_text_state_update_count += 1;
2522            self.text.lamport_clock.observe(lamport_timestamp);
2523            cx.notify();
2524            cx.emit(BufferEvent::DiagnosticsUpdated);
2525        }
2526    }
2527
2528    fn send_operation(&mut self, operation: Operation, is_local: bool, cx: &mut Context<Self>) {
2529        self.was_changed();
2530        cx.emit(BufferEvent::Operation {
2531            operation,
2532            is_local,
2533        });
2534    }
2535
2536    /// Removes the selections for a given peer.
2537    pub fn remove_peer(&mut self, replica_id: ReplicaId, cx: &mut Context<Self>) {
2538        self.remote_selections.remove(&replica_id);
2539        cx.notify();
2540    }
2541
2542    /// Undoes the most recent transaction.
2543    pub fn undo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2544        let was_dirty = self.is_dirty();
2545        let old_version = self.version.clone();
2546
2547        if let Some((transaction_id, operation)) = self.text.undo() {
2548            self.send_operation(Operation::Buffer(operation), true, cx);
2549            self.did_edit(&old_version, was_dirty, cx);
2550            Some(transaction_id)
2551        } else {
2552            None
2553        }
2554    }
2555
2556    /// Manually undoes a specific transaction in the buffer's undo history.
2557    pub fn undo_transaction(
2558        &mut self,
2559        transaction_id: TransactionId,
2560        cx: &mut Context<Self>,
2561    ) -> bool {
2562        let was_dirty = self.is_dirty();
2563        let old_version = self.version.clone();
2564        if let Some(operation) = self.text.undo_transaction(transaction_id) {
2565            self.send_operation(Operation::Buffer(operation), true, cx);
2566            self.did_edit(&old_version, was_dirty, cx);
2567            true
2568        } else {
2569            false
2570        }
2571    }
2572
2573    /// Manually undoes all changes after a given transaction in the buffer's undo history.
2574    pub fn undo_to_transaction(
2575        &mut self,
2576        transaction_id: TransactionId,
2577        cx: &mut Context<Self>,
2578    ) -> bool {
2579        let was_dirty = self.is_dirty();
2580        let old_version = self.version.clone();
2581
2582        let operations = self.text.undo_to_transaction(transaction_id);
2583        let undone = !operations.is_empty();
2584        for operation in operations {
2585            self.send_operation(Operation::Buffer(operation), true, cx);
2586        }
2587        if undone {
2588            self.did_edit(&old_version, was_dirty, cx)
2589        }
2590        undone
2591    }
2592
2593    pub fn undo_operations(&mut self, counts: HashMap<Lamport, u32>, cx: &mut Context<Buffer>) {
2594        let was_dirty = self.is_dirty();
2595        let operation = self.text.undo_operations(counts);
2596        let old_version = self.version.clone();
2597        self.send_operation(Operation::Buffer(operation), true, cx);
2598        self.did_edit(&old_version, was_dirty, cx);
2599    }
2600
2601    /// Manually redoes a specific transaction in the buffer's redo history.
2602    pub fn redo(&mut self, cx: &mut Context<Self>) -> Option<TransactionId> {
2603        let was_dirty = self.is_dirty();
2604        let old_version = self.version.clone();
2605
2606        if let Some((transaction_id, operation)) = self.text.redo() {
2607            self.send_operation(Operation::Buffer(operation), true, cx);
2608            self.did_edit(&old_version, was_dirty, cx);
2609            Some(transaction_id)
2610        } else {
2611            None
2612        }
2613    }
2614
2615    /// Manually undoes all changes until a given transaction in the buffer's redo history.
2616    pub fn redo_to_transaction(
2617        &mut self,
2618        transaction_id: TransactionId,
2619        cx: &mut Context<Self>,
2620    ) -> bool {
2621        let was_dirty = self.is_dirty();
2622        let old_version = self.version.clone();
2623
2624        let operations = self.text.redo_to_transaction(transaction_id);
2625        let redone = !operations.is_empty();
2626        for operation in operations {
2627            self.send_operation(Operation::Buffer(operation), true, cx);
2628        }
2629        if redone {
2630            self.did_edit(&old_version, was_dirty, cx)
2631        }
2632        redone
2633    }
2634
2635    /// Override current completion triggers with the user-provided completion triggers.
2636    pub fn set_completion_triggers(
2637        &mut self,
2638        server_id: LanguageServerId,
2639        triggers: BTreeSet<String>,
2640        cx: &mut Context<Self>,
2641    ) {
2642        self.completion_triggers_timestamp = self.text.lamport_clock.tick();
2643        if triggers.is_empty() {
2644            self.completion_triggers_per_language_server
2645                .remove(&server_id);
2646            self.completion_triggers = self
2647                .completion_triggers_per_language_server
2648                .values()
2649                .flat_map(|triggers| triggers.into_iter().cloned())
2650                .collect();
2651        } else {
2652            self.completion_triggers_per_language_server
2653                .insert(server_id, triggers.clone());
2654            self.completion_triggers.extend(triggers.iter().cloned());
2655        }
2656        self.send_operation(
2657            Operation::UpdateCompletionTriggers {
2658                triggers: triggers.iter().cloned().collect(),
2659                lamport_timestamp: self.completion_triggers_timestamp,
2660                server_id,
2661            },
2662            true,
2663            cx,
2664        );
2665        cx.notify();
2666    }
2667
2668    /// Returns a list of strings which trigger a completion menu for this language.
2669    /// Usually this is driven by LSP server which returns a list of trigger characters for completions.
2670    pub fn completion_triggers(&self) -> &BTreeSet<String> {
2671        &self.completion_triggers
2672    }
2673
2674    /// Call this directly after performing edits to prevent the preview tab
2675    /// from being dismissed by those edits. It causes `should_dismiss_preview`
2676    /// to return false until there are additional edits.
2677    pub fn refresh_preview(&mut self) {
2678        self.preview_version = self.version.clone();
2679    }
2680
2681    /// Whether we should preserve the preview status of a tab containing this buffer.
2682    pub fn preserve_preview(&self) -> bool {
2683        !self.has_edits_since(&self.preview_version)
2684    }
2685}
2686
2687#[doc(hidden)]
2688#[cfg(any(test, feature = "test-support"))]
2689impl Buffer {
2690    pub fn edit_via_marked_text(
2691        &mut self,
2692        marked_string: &str,
2693        autoindent_mode: Option<AutoindentMode>,
2694        cx: &mut Context<Self>,
2695    ) {
2696        let edits = self.edits_for_marked_text(marked_string);
2697        self.edit(edits, autoindent_mode, cx);
2698    }
2699
2700    pub fn set_group_interval(&mut self, group_interval: Duration) {
2701        self.text.set_group_interval(group_interval);
2702    }
2703
2704    pub fn randomly_edit<T>(&mut self, rng: &mut T, old_range_count: usize, cx: &mut Context<Self>)
2705    where
2706        T: rand::Rng,
2707    {
2708        let mut edits: Vec<(Range<usize>, String)> = Vec::new();
2709        let mut last_end = None;
2710        for _ in 0..old_range_count {
2711            if last_end.map_or(false, |last_end| last_end >= self.len()) {
2712                break;
2713            }
2714
2715            let new_start = last_end.map_or(0, |last_end| last_end + 1);
2716            let mut range = self.random_byte_range(new_start, rng);
2717            if rng.gen_bool(0.2) {
2718                mem::swap(&mut range.start, &mut range.end);
2719            }
2720            last_end = Some(range.end);
2721
2722            let new_text_len = rng.gen_range(0..10);
2723            let mut new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect();
2724            new_text = new_text.to_uppercase();
2725
2726            edits.push((range, new_text));
2727        }
2728        log::info!("mutating buffer {} with {:?}", self.replica_id(), edits);
2729        self.edit(edits, None, cx);
2730    }
2731
2732    pub fn randomly_undo_redo(&mut self, rng: &mut impl rand::Rng, cx: &mut Context<Self>) {
2733        let was_dirty = self.is_dirty();
2734        let old_version = self.version.clone();
2735
2736        let ops = self.text.randomly_undo_redo(rng);
2737        if !ops.is_empty() {
2738            for op in ops {
2739                self.send_operation(Operation::Buffer(op), true, cx);
2740                self.did_edit(&old_version, was_dirty, cx);
2741            }
2742        }
2743    }
2744}
2745
2746impl EventEmitter<BufferEvent> for Buffer {}
2747
2748impl Deref for Buffer {
2749    type Target = TextBuffer;
2750
2751    fn deref(&self) -> &Self::Target {
2752        &self.text
2753    }
2754}
2755
2756impl BufferSnapshot {
2757    /// Returns [`IndentSize`] for a given line that respects user settings and
2758    /// language preferences.
2759    pub fn indent_size_for_line(&self, row: u32) -> IndentSize {
2760        indent_size_for_line(self, row)
2761    }
2762
2763    /// Returns [`IndentSize`] for a given position that respects user settings
2764    /// and language preferences.
2765    pub fn language_indent_size_at<T: ToOffset>(&self, position: T, cx: &App) -> IndentSize {
2766        let settings = language_settings(
2767            self.language_at(position).map(|l| l.name()),
2768            self.file(),
2769            cx,
2770        );
2771        if settings.hard_tabs {
2772            IndentSize::tab()
2773        } else {
2774            IndentSize::spaces(settings.tab_size.get())
2775        }
2776    }
2777
2778    /// Retrieve the suggested indent size for all of the given rows. The unit of indentation
2779    /// is passed in as `single_indent_size`.
2780    pub fn suggested_indents(
2781        &self,
2782        rows: impl Iterator<Item = u32>,
2783        single_indent_size: IndentSize,
2784    ) -> BTreeMap<u32, IndentSize> {
2785        let mut result = BTreeMap::new();
2786
2787        for row_range in contiguous_ranges(rows, 10) {
2788            let suggestions = match self.suggest_autoindents(row_range.clone()) {
2789                Some(suggestions) => suggestions,
2790                _ => break,
2791            };
2792
2793            for (row, suggestion) in row_range.zip(suggestions) {
2794                let indent_size = if let Some(suggestion) = suggestion {
2795                    result
2796                        .get(&suggestion.basis_row)
2797                        .copied()
2798                        .unwrap_or_else(|| self.indent_size_for_line(suggestion.basis_row))
2799                        .with_delta(suggestion.delta, single_indent_size)
2800                } else {
2801                    self.indent_size_for_line(row)
2802                };
2803
2804                result.insert(row, indent_size);
2805            }
2806        }
2807
2808        result
2809    }
2810
2811    fn suggest_autoindents(
2812        &self,
2813        row_range: Range<u32>,
2814    ) -> Option<impl Iterator<Item = Option<IndentSuggestion>> + '_> {
2815        let config = &self.language.as_ref()?.config;
2816        let prev_non_blank_row = self.prev_non_blank_row(row_range.start);
2817
2818        // Find the suggested indentation ranges based on the syntax tree.
2819        let start = Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0);
2820        let end = Point::new(row_range.end, 0);
2821        let range = (start..end).to_offset(&self.text);
2822        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2823            Some(&grammar.indents_config.as_ref()?.query)
2824        });
2825        let indent_configs = matches
2826            .grammars()
2827            .iter()
2828            .map(|grammar| grammar.indents_config.as_ref().unwrap())
2829            .collect::<Vec<_>>();
2830
2831        let mut indent_ranges = Vec::<Range<Point>>::new();
2832        let mut outdent_positions = Vec::<Point>::new();
2833        while let Some(mat) = matches.peek() {
2834            let mut start: Option<Point> = None;
2835            let mut end: Option<Point> = None;
2836
2837            let config = &indent_configs[mat.grammar_index];
2838            for capture in mat.captures {
2839                if capture.index == config.indent_capture_ix {
2840                    start.get_or_insert(Point::from_ts_point(capture.node.start_position()));
2841                    end.get_or_insert(Point::from_ts_point(capture.node.end_position()));
2842                } else if Some(capture.index) == config.start_capture_ix {
2843                    start = Some(Point::from_ts_point(capture.node.end_position()));
2844                } else if Some(capture.index) == config.end_capture_ix {
2845                    end = Some(Point::from_ts_point(capture.node.start_position()));
2846                } else if Some(capture.index) == config.outdent_capture_ix {
2847                    outdent_positions.push(Point::from_ts_point(capture.node.start_position()));
2848                }
2849            }
2850
2851            matches.advance();
2852            if let Some((start, end)) = start.zip(end) {
2853                if start.row == end.row {
2854                    continue;
2855                }
2856
2857                let range = start..end;
2858                match indent_ranges.binary_search_by_key(&range.start, |r| r.start) {
2859                    Err(ix) => indent_ranges.insert(ix, range),
2860                    Ok(ix) => {
2861                        let prev_range = &mut indent_ranges[ix];
2862                        prev_range.end = prev_range.end.max(range.end);
2863                    }
2864                }
2865            }
2866        }
2867
2868        let mut error_ranges = Vec::<Range<Point>>::new();
2869        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
2870            grammar.error_query.as_ref()
2871        });
2872        while let Some(mat) = matches.peek() {
2873            let node = mat.captures[0].node;
2874            let start = Point::from_ts_point(node.start_position());
2875            let end = Point::from_ts_point(node.end_position());
2876            let range = start..end;
2877            let ix = match error_ranges.binary_search_by_key(&range.start, |r| r.start) {
2878                Ok(ix) | Err(ix) => ix,
2879            };
2880            let mut end_ix = ix;
2881            while let Some(existing_range) = error_ranges.get(end_ix) {
2882                if existing_range.end < end {
2883                    end_ix += 1;
2884                } else {
2885                    break;
2886                }
2887            }
2888            error_ranges.splice(ix..end_ix, [range]);
2889            matches.advance();
2890        }
2891
2892        outdent_positions.sort();
2893        for outdent_position in outdent_positions {
2894            // find the innermost indent range containing this outdent_position
2895            // set its end to the outdent position
2896            if let Some(range_to_truncate) = indent_ranges
2897                .iter_mut()
2898                .filter(|indent_range| indent_range.contains(&outdent_position))
2899                .last()
2900            {
2901                range_to_truncate.end = outdent_position;
2902            }
2903        }
2904
2905        // Find the suggested indentation increases and decreased based on regexes.
2906        let mut indent_change_rows = Vec::<(u32, Ordering)>::new();
2907        self.for_each_line(
2908            Point::new(prev_non_blank_row.unwrap_or(row_range.start), 0)
2909                ..Point::new(row_range.end, 0),
2910            |row, line| {
2911                if config
2912                    .decrease_indent_pattern
2913                    .as_ref()
2914                    .map_or(false, |regex| regex.is_match(line))
2915                {
2916                    indent_change_rows.push((row, Ordering::Less));
2917                }
2918                if config
2919                    .increase_indent_pattern
2920                    .as_ref()
2921                    .map_or(false, |regex| regex.is_match(line))
2922                {
2923                    indent_change_rows.push((row + 1, Ordering::Greater));
2924                }
2925            },
2926        );
2927
2928        let mut indent_changes = indent_change_rows.into_iter().peekable();
2929        let mut prev_row = if config.auto_indent_using_last_non_empty_line {
2930            prev_non_blank_row.unwrap_or(0)
2931        } else {
2932            row_range.start.saturating_sub(1)
2933        };
2934        let mut prev_row_start = Point::new(prev_row, self.indent_size_for_line(prev_row).len);
2935        Some(row_range.map(move |row| {
2936            let row_start = Point::new(row, self.indent_size_for_line(row).len);
2937
2938            let mut indent_from_prev_row = false;
2939            let mut outdent_from_prev_row = false;
2940            let mut outdent_to_row = u32::MAX;
2941            let mut from_regex = false;
2942
2943            while let Some((indent_row, delta)) = indent_changes.peek() {
2944                match indent_row.cmp(&row) {
2945                    Ordering::Equal => match delta {
2946                        Ordering::Less => {
2947                            from_regex = true;
2948                            outdent_from_prev_row = true
2949                        }
2950                        Ordering::Greater => {
2951                            indent_from_prev_row = true;
2952                            from_regex = true
2953                        }
2954                        _ => {}
2955                    },
2956
2957                    Ordering::Greater => break,
2958                    Ordering::Less => {}
2959                }
2960
2961                indent_changes.next();
2962            }
2963
2964            for range in &indent_ranges {
2965                if range.start.row >= row {
2966                    break;
2967                }
2968                if range.start.row == prev_row && range.end > row_start {
2969                    indent_from_prev_row = true;
2970                }
2971                if range.end > prev_row_start && range.end <= row_start {
2972                    outdent_to_row = outdent_to_row.min(range.start.row);
2973                }
2974            }
2975
2976            let within_error = error_ranges
2977                .iter()
2978                .any(|e| e.start.row < row && e.end > row_start);
2979
2980            let suggestion = if outdent_to_row == prev_row
2981                || (outdent_from_prev_row && indent_from_prev_row)
2982            {
2983                Some(IndentSuggestion {
2984                    basis_row: prev_row,
2985                    delta: Ordering::Equal,
2986                    within_error: within_error && !from_regex,
2987                })
2988            } else if indent_from_prev_row {
2989                Some(IndentSuggestion {
2990                    basis_row: prev_row,
2991                    delta: Ordering::Greater,
2992                    within_error: within_error && !from_regex,
2993                })
2994            } else if outdent_to_row < prev_row {
2995                Some(IndentSuggestion {
2996                    basis_row: outdent_to_row,
2997                    delta: Ordering::Equal,
2998                    within_error: within_error && !from_regex,
2999                })
3000            } else if outdent_from_prev_row {
3001                Some(IndentSuggestion {
3002                    basis_row: prev_row,
3003                    delta: Ordering::Less,
3004                    within_error: within_error && !from_regex,
3005                })
3006            } else if config.auto_indent_using_last_non_empty_line || !self.is_line_blank(prev_row)
3007            {
3008                Some(IndentSuggestion {
3009                    basis_row: prev_row,
3010                    delta: Ordering::Equal,
3011                    within_error: within_error && !from_regex,
3012                })
3013            } else {
3014                None
3015            };
3016
3017            prev_row = row;
3018            prev_row_start = row_start;
3019            suggestion
3020        }))
3021    }
3022
3023    fn prev_non_blank_row(&self, mut row: u32) -> Option<u32> {
3024        while row > 0 {
3025            row -= 1;
3026            if !self.is_line_blank(row) {
3027                return Some(row);
3028            }
3029        }
3030        None
3031    }
3032
3033    fn get_highlights(&self, range: Range<usize>) -> (SyntaxMapCaptures, Vec<HighlightMap>) {
3034        let captures = self.syntax.captures(range, &self.text, |grammar| {
3035            grammar.highlights_query.as_ref()
3036        });
3037        let highlight_maps = captures
3038            .grammars()
3039            .iter()
3040            .map(|grammar| grammar.highlight_map())
3041            .collect();
3042        (captures, highlight_maps)
3043    }
3044
3045    /// Iterates over chunks of text in the given range of the buffer. Text is chunked
3046    /// in an arbitrary way due to being stored in a [`Rope`](text::Rope). The text is also
3047    /// returned in chunks where each chunk has a single syntax highlighting style and
3048    /// diagnostic status.
3049    pub fn chunks<T: ToOffset>(&self, range: Range<T>, language_aware: bool) -> BufferChunks {
3050        let range = range.start.to_offset(self)..range.end.to_offset(self);
3051
3052        let mut syntax = None;
3053        if language_aware {
3054            syntax = Some(self.get_highlights(range.clone()));
3055        }
3056        // We want to look at diagnostic spans only when iterating over language-annotated chunks.
3057        let diagnostics = language_aware;
3058        BufferChunks::new(self.text.as_rope(), range, syntax, diagnostics, Some(self))
3059    }
3060
3061    pub fn highlighted_text_for_range<T: ToOffset>(
3062        &self,
3063        range: Range<T>,
3064        override_style: Option<HighlightStyle>,
3065        syntax_theme: &SyntaxTheme,
3066    ) -> HighlightedText {
3067        HighlightedText::from_buffer_range(
3068            range,
3069            &self.text,
3070            &self.syntax,
3071            override_style,
3072            syntax_theme,
3073        )
3074    }
3075
3076    /// Invokes the given callback for each line of text in the given range of the buffer.
3077    /// Uses callback to avoid allocating a string for each line.
3078    fn for_each_line(&self, range: Range<Point>, mut callback: impl FnMut(u32, &str)) {
3079        let mut line = String::new();
3080        let mut row = range.start.row;
3081        for chunk in self
3082            .as_rope()
3083            .chunks_in_range(range.to_offset(self))
3084            .chain(["\n"])
3085        {
3086            for (newline_ix, text) in chunk.split('\n').enumerate() {
3087                if newline_ix > 0 {
3088                    callback(row, &line);
3089                    row += 1;
3090                    line.clear();
3091                }
3092                line.push_str(text);
3093            }
3094        }
3095    }
3096
3097    /// Iterates over every [`SyntaxLayer`] in the buffer.
3098    pub fn syntax_layers(&self) -> impl Iterator<Item = SyntaxLayer> + '_ {
3099        self.syntax
3100            .layers_for_range(0..self.len(), &self.text, true)
3101    }
3102
3103    pub fn syntax_layer_at<D: ToOffset>(&self, position: D) -> Option<SyntaxLayer> {
3104        let offset = position.to_offset(self);
3105        self.syntax
3106            .layers_for_range(offset..offset, &self.text, false)
3107            .filter(|l| l.node().end_byte() > offset)
3108            .last()
3109    }
3110
3111    pub fn smallest_syntax_layer_containing<D: ToOffset>(
3112        &self,
3113        range: Range<D>,
3114    ) -> Option<SyntaxLayer> {
3115        let range = range.to_offset(self);
3116        return self
3117            .syntax
3118            .layers_for_range(range, &self.text, false)
3119            .max_by(|a, b| {
3120                if a.depth != b.depth {
3121                    a.depth.cmp(&b.depth)
3122                } else if a.offset.0 != b.offset.0 {
3123                    a.offset.0.cmp(&b.offset.0)
3124                } else {
3125                    a.node().end_byte().cmp(&b.node().end_byte()).reverse()
3126                }
3127            });
3128    }
3129
3130    /// Returns the main [`Language`].
3131    pub fn language(&self) -> Option<&Arc<Language>> {
3132        self.language.as_ref()
3133    }
3134
3135    /// Returns the [`Language`] at the given location.
3136    pub fn language_at<D: ToOffset>(&self, position: D) -> Option<&Arc<Language>> {
3137        self.syntax_layer_at(position)
3138            .map(|info| info.language)
3139            .or(self.language.as_ref())
3140    }
3141
3142    /// Returns the settings for the language at the given location.
3143    pub fn settings_at<'a, D: ToOffset>(
3144        &'a self,
3145        position: D,
3146        cx: &'a App,
3147    ) -> Cow<'a, LanguageSettings> {
3148        language_settings(
3149            self.language_at(position).map(|l| l.name()),
3150            self.file.as_ref(),
3151            cx,
3152        )
3153    }
3154
3155    pub fn char_classifier_at<T: ToOffset>(&self, point: T) -> CharClassifier {
3156        CharClassifier::new(self.language_scope_at(point))
3157    }
3158
3159    /// Returns the [`LanguageScope`] at the given location.
3160    pub fn language_scope_at<D: ToOffset>(&self, position: D) -> Option<LanguageScope> {
3161        let offset = position.to_offset(self);
3162        let mut scope = None;
3163        let mut smallest_range: Option<Range<usize>> = None;
3164
3165        // Use the layer that has the smallest node intersecting the given point.
3166        for layer in self
3167            .syntax
3168            .layers_for_range(offset..offset, &self.text, false)
3169        {
3170            let mut cursor = layer.node().walk();
3171
3172            let mut range = None;
3173            loop {
3174                let child_range = cursor.node().byte_range();
3175                if !child_range.to_inclusive().contains(&offset) {
3176                    break;
3177                }
3178
3179                range = Some(child_range);
3180                if cursor.goto_first_child_for_byte(offset).is_none() {
3181                    break;
3182                }
3183            }
3184
3185            if let Some(range) = range {
3186                if smallest_range
3187                    .as_ref()
3188                    .map_or(true, |smallest_range| range.len() < smallest_range.len())
3189                {
3190                    smallest_range = Some(range);
3191                    scope = Some(LanguageScope {
3192                        language: layer.language.clone(),
3193                        override_id: layer.override_id(offset, &self.text),
3194                    });
3195                }
3196            }
3197        }
3198
3199        scope.or_else(|| {
3200            self.language.clone().map(|language| LanguageScope {
3201                language,
3202                override_id: None,
3203            })
3204        })
3205    }
3206
3207    /// Returns a tuple of the range and character kind of the word
3208    /// surrounding the given position.
3209    pub fn surrounding_word<T: ToOffset>(&self, start: T) -> (Range<usize>, Option<CharKind>) {
3210        let mut start = start.to_offset(self);
3211        let mut end = start;
3212        let mut next_chars = self.chars_at(start).peekable();
3213        let mut prev_chars = self.reversed_chars_at(start).peekable();
3214
3215        let classifier = self.char_classifier_at(start);
3216        let word_kind = cmp::max(
3217            prev_chars.peek().copied().map(|c| classifier.kind(c)),
3218            next_chars.peek().copied().map(|c| classifier.kind(c)),
3219        );
3220
3221        for ch in prev_chars {
3222            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3223                start -= ch.len_utf8();
3224            } else {
3225                break;
3226            }
3227        }
3228
3229        for ch in next_chars {
3230            if Some(classifier.kind(ch)) == word_kind && ch != '\n' {
3231                end += ch.len_utf8();
3232            } else {
3233                break;
3234            }
3235        }
3236
3237        (start..end, word_kind)
3238    }
3239
3240    /// Returns the closest syntax node enclosing the given range.
3241    pub fn syntax_ancestor<'a, T: ToOffset>(
3242        &'a self,
3243        range: Range<T>,
3244    ) -> Option<tree_sitter::Node<'a>> {
3245        let range = range.start.to_offset(self)..range.end.to_offset(self);
3246        let mut result: Option<tree_sitter::Node<'a>> = None;
3247        'outer: for layer in self
3248            .syntax
3249            .layers_for_range(range.clone(), &self.text, true)
3250        {
3251            let mut cursor = layer.node().walk();
3252
3253            // Descend to the first leaf that touches the start of the range,
3254            // and if the range is non-empty, extends beyond the start.
3255            while cursor.goto_first_child_for_byte(range.start).is_some() {
3256                if !range.is_empty() && cursor.node().end_byte() == range.start {
3257                    cursor.goto_next_sibling();
3258                }
3259            }
3260
3261            // Ascend to the smallest ancestor that strictly contains the range.
3262            loop {
3263                let node_range = cursor.node().byte_range();
3264                if node_range.start <= range.start
3265                    && node_range.end >= range.end
3266                    && node_range.len() > range.len()
3267                {
3268                    break;
3269                }
3270                if !cursor.goto_parent() {
3271                    continue 'outer;
3272                }
3273            }
3274
3275            let left_node = cursor.node();
3276            let mut layer_result = left_node;
3277
3278            // For an empty range, try to find another node immediately to the right of the range.
3279            if left_node.end_byte() == range.start {
3280                let mut right_node = None;
3281                while !cursor.goto_next_sibling() {
3282                    if !cursor.goto_parent() {
3283                        break;
3284                    }
3285                }
3286
3287                while cursor.node().start_byte() == range.start {
3288                    right_node = Some(cursor.node());
3289                    if !cursor.goto_first_child() {
3290                        break;
3291                    }
3292                }
3293
3294                // If there is a candidate node on both sides of the (empty) range, then
3295                // decide between the two by favoring a named node over an anonymous token.
3296                // If both nodes are the same in that regard, favor the right one.
3297                if let Some(right_node) = right_node {
3298                    if right_node.is_named() || !left_node.is_named() {
3299                        layer_result = right_node;
3300                    }
3301                }
3302            }
3303
3304            if let Some(previous_result) = &result {
3305                if previous_result.byte_range().len() < layer_result.byte_range().len() {
3306                    continue;
3307                }
3308            }
3309            result = Some(layer_result);
3310        }
3311
3312        result
3313    }
3314
3315    /// Returns the outline for the buffer.
3316    ///
3317    /// This method allows passing an optional [`SyntaxTheme`] to
3318    /// syntax-highlight the returned symbols.
3319    pub fn outline(&self, theme: Option<&SyntaxTheme>) -> Option<Outline<Anchor>> {
3320        self.outline_items_containing(0..self.len(), true, theme)
3321            .map(Outline::new)
3322    }
3323
3324    /// Returns all the symbols that contain the given position.
3325    ///
3326    /// This method allows passing an optional [`SyntaxTheme`] to
3327    /// syntax-highlight the returned symbols.
3328    pub fn symbols_containing<T: ToOffset>(
3329        &self,
3330        position: T,
3331        theme: Option<&SyntaxTheme>,
3332    ) -> Option<Vec<OutlineItem<Anchor>>> {
3333        let position = position.to_offset(self);
3334        let mut items = self.outline_items_containing(
3335            position.saturating_sub(1)..self.len().min(position + 1),
3336            false,
3337            theme,
3338        )?;
3339        let mut prev_depth = None;
3340        items.retain(|item| {
3341            let result = prev_depth.map_or(true, |prev_depth| item.depth > prev_depth);
3342            prev_depth = Some(item.depth);
3343            result
3344        });
3345        Some(items)
3346    }
3347
3348    pub fn outline_range_containing<T: ToOffset>(&self, range: Range<T>) -> Option<Range<Point>> {
3349        let range = range.to_offset(self);
3350        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3351            grammar.outline_config.as_ref().map(|c| &c.query)
3352        });
3353        let configs = matches
3354            .grammars()
3355            .iter()
3356            .map(|g| g.outline_config.as_ref().unwrap())
3357            .collect::<Vec<_>>();
3358
3359        while let Some(mat) = matches.peek() {
3360            let config = &configs[mat.grammar_index];
3361            let containing_item_node = maybe!({
3362                let item_node = mat.captures.iter().find_map(|cap| {
3363                    if cap.index == config.item_capture_ix {
3364                        Some(cap.node)
3365                    } else {
3366                        None
3367                    }
3368                })?;
3369
3370                let item_byte_range = item_node.byte_range();
3371                if item_byte_range.end < range.start || item_byte_range.start > range.end {
3372                    None
3373                } else {
3374                    Some(item_node)
3375                }
3376            });
3377
3378            if let Some(item_node) = containing_item_node {
3379                return Some(
3380                    Point::from_ts_point(item_node.start_position())
3381                        ..Point::from_ts_point(item_node.end_position()),
3382                );
3383            }
3384
3385            matches.advance();
3386        }
3387        None
3388    }
3389
3390    pub fn outline_items_containing<T: ToOffset>(
3391        &self,
3392        range: Range<T>,
3393        include_extra_context: bool,
3394        theme: Option<&SyntaxTheme>,
3395    ) -> Option<Vec<OutlineItem<Anchor>>> {
3396        let range = range.to_offset(self);
3397        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3398            grammar.outline_config.as_ref().map(|c| &c.query)
3399        });
3400        let configs = matches
3401            .grammars()
3402            .iter()
3403            .map(|g| g.outline_config.as_ref().unwrap())
3404            .collect::<Vec<_>>();
3405
3406        let mut items = Vec::new();
3407        let mut annotation_row_ranges: Vec<Range<u32>> = Vec::new();
3408        while let Some(mat) = matches.peek() {
3409            let config = &configs[mat.grammar_index];
3410            if let Some(item) =
3411                self.next_outline_item(config, &mat, &range, include_extra_context, theme)
3412            {
3413                items.push(item);
3414            } else if let Some(capture) = mat
3415                .captures
3416                .iter()
3417                .find(|capture| Some(capture.index) == config.annotation_capture_ix)
3418            {
3419                let capture_range = capture.node.start_position()..capture.node.end_position();
3420                let mut capture_row_range =
3421                    capture_range.start.row as u32..capture_range.end.row as u32;
3422                if capture_range.end.row > capture_range.start.row && capture_range.end.column == 0
3423                {
3424                    capture_row_range.end -= 1;
3425                }
3426                if let Some(last_row_range) = annotation_row_ranges.last_mut() {
3427                    if last_row_range.end >= capture_row_range.start.saturating_sub(1) {
3428                        last_row_range.end = capture_row_range.end;
3429                    } else {
3430                        annotation_row_ranges.push(capture_row_range);
3431                    }
3432                } else {
3433                    annotation_row_ranges.push(capture_row_range);
3434                }
3435            }
3436            matches.advance();
3437        }
3438
3439        items.sort_by_key(|item| (item.range.start, Reverse(item.range.end)));
3440
3441        // Assign depths based on containment relationships and convert to anchors.
3442        let mut item_ends_stack = Vec::<Point>::new();
3443        let mut anchor_items = Vec::new();
3444        let mut annotation_row_ranges = annotation_row_ranges.into_iter().peekable();
3445        for item in items {
3446            while let Some(last_end) = item_ends_stack.last().copied() {
3447                if last_end < item.range.end {
3448                    item_ends_stack.pop();
3449                } else {
3450                    break;
3451                }
3452            }
3453
3454            let mut annotation_row_range = None;
3455            while let Some(next_annotation_row_range) = annotation_row_ranges.peek() {
3456                let row_preceding_item = item.range.start.row.saturating_sub(1);
3457                if next_annotation_row_range.end < row_preceding_item {
3458                    annotation_row_ranges.next();
3459                } else {
3460                    if next_annotation_row_range.end == row_preceding_item {
3461                        annotation_row_range = Some(next_annotation_row_range.clone());
3462                        annotation_row_ranges.next();
3463                    }
3464                    break;
3465                }
3466            }
3467
3468            anchor_items.push(OutlineItem {
3469                depth: item_ends_stack.len(),
3470                range: self.anchor_after(item.range.start)..self.anchor_before(item.range.end),
3471                text: item.text,
3472                highlight_ranges: item.highlight_ranges,
3473                name_ranges: item.name_ranges,
3474                body_range: item.body_range.map(|body_range| {
3475                    self.anchor_after(body_range.start)..self.anchor_before(body_range.end)
3476                }),
3477                annotation_range: annotation_row_range.map(|annotation_range| {
3478                    self.anchor_after(Point::new(annotation_range.start, 0))
3479                        ..self.anchor_before(Point::new(
3480                            annotation_range.end,
3481                            self.line_len(annotation_range.end),
3482                        ))
3483                }),
3484            });
3485            item_ends_stack.push(item.range.end);
3486        }
3487
3488        Some(anchor_items)
3489    }
3490
3491    fn next_outline_item(
3492        &self,
3493        config: &OutlineConfig,
3494        mat: &SyntaxMapMatch,
3495        range: &Range<usize>,
3496        include_extra_context: bool,
3497        theme: Option<&SyntaxTheme>,
3498    ) -> Option<OutlineItem<Point>> {
3499        let item_node = mat.captures.iter().find_map(|cap| {
3500            if cap.index == config.item_capture_ix {
3501                Some(cap.node)
3502            } else {
3503                None
3504            }
3505        })?;
3506
3507        let item_byte_range = item_node.byte_range();
3508        if item_byte_range.end < range.start || item_byte_range.start > range.end {
3509            return None;
3510        }
3511        let item_point_range = Point::from_ts_point(item_node.start_position())
3512            ..Point::from_ts_point(item_node.end_position());
3513
3514        let mut open_point = None;
3515        let mut close_point = None;
3516        let mut buffer_ranges = Vec::new();
3517        for capture in mat.captures {
3518            let node_is_name;
3519            if capture.index == config.name_capture_ix {
3520                node_is_name = true;
3521            } else if Some(capture.index) == config.context_capture_ix
3522                || (Some(capture.index) == config.extra_context_capture_ix && include_extra_context)
3523            {
3524                node_is_name = false;
3525            } else {
3526                if Some(capture.index) == config.open_capture_ix {
3527                    open_point = Some(Point::from_ts_point(capture.node.end_position()));
3528                } else if Some(capture.index) == config.close_capture_ix {
3529                    close_point = Some(Point::from_ts_point(capture.node.start_position()));
3530                }
3531
3532                continue;
3533            }
3534
3535            let mut range = capture.node.start_byte()..capture.node.end_byte();
3536            let start = capture.node.start_position();
3537            if capture.node.end_position().row > start.row {
3538                range.end = range.start + self.line_len(start.row as u32) as usize - start.column;
3539            }
3540
3541            if !range.is_empty() {
3542                buffer_ranges.push((range, node_is_name));
3543            }
3544        }
3545        if buffer_ranges.is_empty() {
3546            return None;
3547        }
3548        let mut text = String::new();
3549        let mut highlight_ranges = Vec::new();
3550        let mut name_ranges = Vec::new();
3551        let mut chunks = self.chunks(
3552            buffer_ranges.first().unwrap().0.start..buffer_ranges.last().unwrap().0.end,
3553            true,
3554        );
3555        let mut last_buffer_range_end = 0;
3556
3557        for (buffer_range, is_name) in buffer_ranges {
3558            let space_added = !text.is_empty() && buffer_range.start > last_buffer_range_end;
3559            if space_added {
3560                text.push(' ');
3561            }
3562            let before_append_len = text.len();
3563            let mut offset = buffer_range.start;
3564            chunks.seek(buffer_range.clone());
3565            for mut chunk in chunks.by_ref() {
3566                if chunk.text.len() > buffer_range.end - offset {
3567                    chunk.text = &chunk.text[0..(buffer_range.end - offset)];
3568                    offset = buffer_range.end;
3569                } else {
3570                    offset += chunk.text.len();
3571                }
3572                let style = chunk
3573                    .syntax_highlight_id
3574                    .zip(theme)
3575                    .and_then(|(highlight, theme)| highlight.style(theme));
3576                if let Some(style) = style {
3577                    let start = text.len();
3578                    let end = start + chunk.text.len();
3579                    highlight_ranges.push((start..end, style));
3580                }
3581                text.push_str(chunk.text);
3582                if offset >= buffer_range.end {
3583                    break;
3584                }
3585            }
3586            if is_name {
3587                let after_append_len = text.len();
3588                let start = if space_added && !name_ranges.is_empty() {
3589                    before_append_len - 1
3590                } else {
3591                    before_append_len
3592                };
3593                name_ranges.push(start..after_append_len);
3594            }
3595            last_buffer_range_end = buffer_range.end;
3596        }
3597
3598        Some(OutlineItem {
3599            depth: 0, // We'll calculate the depth later
3600            range: item_point_range,
3601            text,
3602            highlight_ranges,
3603            name_ranges,
3604            body_range: open_point.zip(close_point).map(|(start, end)| start..end),
3605            annotation_range: None,
3606        })
3607    }
3608
3609    pub fn function_body_fold_ranges<T: ToOffset>(
3610        &self,
3611        within: Range<T>,
3612    ) -> impl Iterator<Item = Range<usize>> + '_ {
3613        self.text_object_ranges(within, TreeSitterOptions::default())
3614            .filter_map(|(range, obj)| (obj == TextObject::InsideFunction).then_some(range))
3615    }
3616
3617    /// For each grammar in the language, runs the provided
3618    /// [`tree_sitter::Query`] against the given range.
3619    pub fn matches(
3620        &self,
3621        range: Range<usize>,
3622        query: fn(&Grammar) -> Option<&tree_sitter::Query>,
3623    ) -> SyntaxMapMatches {
3624        self.syntax.matches(range, self, query)
3625    }
3626
3627    pub fn all_bracket_ranges(
3628        &self,
3629        range: Range<usize>,
3630    ) -> impl Iterator<Item = BracketMatch> + '_ {
3631        let mut matches = self.syntax.matches(range.clone(), &self.text, |grammar| {
3632            grammar.brackets_config.as_ref().map(|c| &c.query)
3633        });
3634        let configs = matches
3635            .grammars()
3636            .iter()
3637            .map(|grammar| grammar.brackets_config.as_ref().unwrap())
3638            .collect::<Vec<_>>();
3639
3640        iter::from_fn(move || {
3641            while let Some(mat) = matches.peek() {
3642                let mut open = None;
3643                let mut close = None;
3644                let config = &configs[mat.grammar_index];
3645                let pattern = &config.patterns[mat.pattern_index];
3646                for capture in mat.captures {
3647                    if capture.index == config.open_capture_ix {
3648                        open = Some(capture.node.byte_range());
3649                    } else if capture.index == config.close_capture_ix {
3650                        close = Some(capture.node.byte_range());
3651                    }
3652                }
3653
3654                matches.advance();
3655
3656                let Some((open_range, close_range)) = open.zip(close) else {
3657                    continue;
3658                };
3659
3660                let bracket_range = open_range.start..=close_range.end;
3661                if !bracket_range.overlaps(&range) {
3662                    continue;
3663                }
3664
3665                return Some(BracketMatch {
3666                    open_range,
3667                    close_range,
3668                    newline_only: pattern.newline_only,
3669                });
3670            }
3671            None
3672        })
3673    }
3674
3675    /// Returns bracket range pairs overlapping or adjacent to `range`
3676    pub fn bracket_ranges<T: ToOffset>(
3677        &self,
3678        range: Range<T>,
3679    ) -> impl Iterator<Item = BracketMatch> + '_ {
3680        // Find bracket pairs that *inclusively* contain the given range.
3681        let range = range.start.to_offset(self).saturating_sub(1)
3682            ..self.len().min(range.end.to_offset(self) + 1);
3683        self.all_bracket_ranges(range)
3684            .filter(|pair| !pair.newline_only)
3685    }
3686
3687    pub fn text_object_ranges<T: ToOffset>(
3688        &self,
3689        range: Range<T>,
3690        options: TreeSitterOptions,
3691    ) -> impl Iterator<Item = (Range<usize>, TextObject)> + '_ {
3692        let range = range.start.to_offset(self).saturating_sub(1)
3693            ..self.len().min(range.end.to_offset(self) + 1);
3694
3695        let mut matches =
3696            self.syntax
3697                .matches_with_options(range.clone(), &self.text, options, |grammar| {
3698                    grammar.text_object_config.as_ref().map(|c| &c.query)
3699                });
3700
3701        let configs = matches
3702            .grammars()
3703            .iter()
3704            .map(|grammar| grammar.text_object_config.as_ref())
3705            .collect::<Vec<_>>();
3706
3707        let mut captures = Vec::<(Range<usize>, TextObject)>::new();
3708
3709        iter::from_fn(move || loop {
3710            while let Some(capture) = captures.pop() {
3711                if capture.0.overlaps(&range) {
3712                    return Some(capture);
3713                }
3714            }
3715
3716            let mat = matches.peek()?;
3717
3718            let Some(config) = configs[mat.grammar_index].as_ref() else {
3719                matches.advance();
3720                continue;
3721            };
3722
3723            for capture in mat.captures {
3724                let Some(ix) = config
3725                    .text_objects_by_capture_ix
3726                    .binary_search_by_key(&capture.index, |e| e.0)
3727                    .ok()
3728                else {
3729                    continue;
3730                };
3731                let text_object = config.text_objects_by_capture_ix[ix].1;
3732                let byte_range = capture.node.byte_range();
3733
3734                let mut found = false;
3735                for (range, existing) in captures.iter_mut() {
3736                    if existing == &text_object {
3737                        range.start = range.start.min(byte_range.start);
3738                        range.end = range.end.max(byte_range.end);
3739                        found = true;
3740                        break;
3741                    }
3742                }
3743
3744                if !found {
3745                    captures.push((byte_range, text_object));
3746                }
3747            }
3748
3749            matches.advance();
3750        })
3751    }
3752
3753    /// Returns enclosing bracket ranges containing the given range
3754    pub fn enclosing_bracket_ranges<T: ToOffset>(
3755        &self,
3756        range: Range<T>,
3757    ) -> impl Iterator<Item = BracketMatch> + '_ {
3758        let range = range.start.to_offset(self)..range.end.to_offset(self);
3759
3760        self.bracket_ranges(range.clone()).filter(move |pair| {
3761            pair.open_range.start <= range.start && pair.close_range.end >= range.end
3762        })
3763    }
3764
3765    /// Returns the smallest enclosing bracket ranges containing the given range or None if no brackets contain range
3766    ///
3767    /// Can optionally pass a range_filter to filter the ranges of brackets to consider
3768    pub fn innermost_enclosing_bracket_ranges<T: ToOffset>(
3769        &self,
3770        range: Range<T>,
3771        range_filter: Option<&dyn Fn(Range<usize>, Range<usize>) -> bool>,
3772    ) -> Option<(Range<usize>, Range<usize>)> {
3773        let range = range.start.to_offset(self)..range.end.to_offset(self);
3774
3775        // Get the ranges of the innermost pair of brackets.
3776        let mut result: Option<(Range<usize>, Range<usize>)> = None;
3777
3778        for pair in self.enclosing_bracket_ranges(range.clone()) {
3779            if let Some(range_filter) = range_filter {
3780                if !range_filter(pair.open_range.clone(), pair.close_range.clone()) {
3781                    continue;
3782                }
3783            }
3784
3785            let len = pair.close_range.end - pair.open_range.start;
3786
3787            if let Some((existing_open, existing_close)) = &result {
3788                let existing_len = existing_close.end - existing_open.start;
3789                if len > existing_len {
3790                    continue;
3791                }
3792            }
3793
3794            result = Some((pair.open_range, pair.close_range));
3795        }
3796
3797        result
3798    }
3799
3800    /// Returns anchor ranges for any matches of the redaction query.
3801    /// The buffer can be associated with multiple languages, and the redaction query associated with each
3802    /// will be run on the relevant section of the buffer.
3803    pub fn redacted_ranges<T: ToOffset>(
3804        &self,
3805        range: Range<T>,
3806    ) -> impl Iterator<Item = Range<usize>> + '_ {
3807        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3808        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3809            grammar
3810                .redactions_config
3811                .as_ref()
3812                .map(|config| &config.query)
3813        });
3814
3815        let configs = syntax_matches
3816            .grammars()
3817            .iter()
3818            .map(|grammar| grammar.redactions_config.as_ref())
3819            .collect::<Vec<_>>();
3820
3821        iter::from_fn(move || {
3822            let redacted_range = syntax_matches
3823                .peek()
3824                .and_then(|mat| {
3825                    configs[mat.grammar_index].and_then(|config| {
3826                        mat.captures
3827                            .iter()
3828                            .find(|capture| capture.index == config.redaction_capture_ix)
3829                    })
3830                })
3831                .map(|mat| mat.node.byte_range());
3832            syntax_matches.advance();
3833            redacted_range
3834        })
3835    }
3836
3837    pub fn injections_intersecting_range<T: ToOffset>(
3838        &self,
3839        range: Range<T>,
3840    ) -> impl Iterator<Item = (Range<usize>, &Arc<Language>)> + '_ {
3841        let offset_range = range.start.to_offset(self)..range.end.to_offset(self);
3842
3843        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3844            grammar
3845                .injection_config
3846                .as_ref()
3847                .map(|config| &config.query)
3848        });
3849
3850        let configs = syntax_matches
3851            .grammars()
3852            .iter()
3853            .map(|grammar| grammar.injection_config.as_ref())
3854            .collect::<Vec<_>>();
3855
3856        iter::from_fn(move || {
3857            let ranges = syntax_matches.peek().and_then(|mat| {
3858                let config = &configs[mat.grammar_index]?;
3859                let content_capture_range = mat.captures.iter().find_map(|capture| {
3860                    if capture.index == config.content_capture_ix {
3861                        Some(capture.node.byte_range())
3862                    } else {
3863                        None
3864                    }
3865                })?;
3866                let language = self.language_at(content_capture_range.start)?;
3867                Some((content_capture_range, language))
3868            });
3869            syntax_matches.advance();
3870            ranges
3871        })
3872    }
3873
3874    pub fn runnable_ranges(
3875        &self,
3876        offset_range: Range<usize>,
3877    ) -> impl Iterator<Item = RunnableRange> + '_ {
3878        let mut syntax_matches = self.syntax.matches(offset_range, self, |grammar| {
3879            grammar.runnable_config.as_ref().map(|config| &config.query)
3880        });
3881
3882        let test_configs = syntax_matches
3883            .grammars()
3884            .iter()
3885            .map(|grammar| grammar.runnable_config.as_ref())
3886            .collect::<Vec<_>>();
3887
3888        iter::from_fn(move || loop {
3889            let mat = syntax_matches.peek()?;
3890
3891            let test_range = test_configs[mat.grammar_index].and_then(|test_configs| {
3892                let mut run_range = None;
3893                let full_range = mat.captures.iter().fold(
3894                    Range {
3895                        start: usize::MAX,
3896                        end: 0,
3897                    },
3898                    |mut acc, next| {
3899                        let byte_range = next.node.byte_range();
3900                        if acc.start > byte_range.start {
3901                            acc.start = byte_range.start;
3902                        }
3903                        if acc.end < byte_range.end {
3904                            acc.end = byte_range.end;
3905                        }
3906                        acc
3907                    },
3908                );
3909                if full_range.start > full_range.end {
3910                    // We did not find a full spanning range of this match.
3911                    return None;
3912                }
3913                let extra_captures: SmallVec<[_; 1]> =
3914                    SmallVec::from_iter(mat.captures.iter().filter_map(|capture| {
3915                        test_configs
3916                            .extra_captures
3917                            .get(capture.index as usize)
3918                            .cloned()
3919                            .and_then(|tag_name| match tag_name {
3920                                RunnableCapture::Named(name) => {
3921                                    Some((capture.node.byte_range(), name))
3922                                }
3923                                RunnableCapture::Run => {
3924                                    let _ = run_range.insert(capture.node.byte_range());
3925                                    None
3926                                }
3927                            })
3928                    }));
3929                let run_range = run_range?;
3930                let tags = test_configs
3931                    .query
3932                    .property_settings(mat.pattern_index)
3933                    .iter()
3934                    .filter_map(|property| {
3935                        if *property.key == *"tag" {
3936                            property
3937                                .value
3938                                .as_ref()
3939                                .map(|value| RunnableTag(value.to_string().into()))
3940                        } else {
3941                            None
3942                        }
3943                    })
3944                    .collect();
3945                let extra_captures = extra_captures
3946                    .into_iter()
3947                    .map(|(range, name)| {
3948                        (
3949                            name.to_string(),
3950                            self.text_for_range(range.clone()).collect::<String>(),
3951                        )
3952                    })
3953                    .collect();
3954                // All tags should have the same range.
3955                Some(RunnableRange {
3956                    run_range,
3957                    full_range,
3958                    runnable: Runnable {
3959                        tags,
3960                        language: mat.language,
3961                        buffer: self.remote_id(),
3962                    },
3963                    extra_captures,
3964                    buffer_id: self.remote_id(),
3965                })
3966            });
3967
3968            syntax_matches.advance();
3969            if test_range.is_some() {
3970                // It's fine for us to short-circuit on .peek()? returning None. We don't want to return None from this iter if we
3971                // had a capture that did not contain a run marker, hence we'll just loop around for the next capture.
3972                return test_range;
3973            }
3974        })
3975    }
3976
3977    /// Returns selections for remote peers intersecting the given range.
3978    #[allow(clippy::type_complexity)]
3979    pub fn selections_in_range(
3980        &self,
3981        range: Range<Anchor>,
3982        include_local: bool,
3983    ) -> impl Iterator<
3984        Item = (
3985            ReplicaId,
3986            bool,
3987            CursorShape,
3988            impl Iterator<Item = &Selection<Anchor>> + '_,
3989        ),
3990    > + '_ {
3991        self.remote_selections
3992            .iter()
3993            .filter(move |(replica_id, set)| {
3994                (include_local || **replica_id != self.text.replica_id())
3995                    && !set.selections.is_empty()
3996            })
3997            .map(move |(replica_id, set)| {
3998                let start_ix = match set.selections.binary_search_by(|probe| {
3999                    probe.end.cmp(&range.start, self).then(Ordering::Greater)
4000                }) {
4001                    Ok(ix) | Err(ix) => ix,
4002                };
4003                let end_ix = match set.selections.binary_search_by(|probe| {
4004                    probe.start.cmp(&range.end, self).then(Ordering::Less)
4005                }) {
4006                    Ok(ix) | Err(ix) => ix,
4007                };
4008
4009                (
4010                    *replica_id,
4011                    set.line_mode,
4012                    set.cursor_shape,
4013                    set.selections[start_ix..end_ix].iter(),
4014                )
4015            })
4016    }
4017
4018    /// Returns if the buffer contains any diagnostics.
4019    pub fn has_diagnostics(&self) -> bool {
4020        !self.diagnostics.is_empty()
4021    }
4022
4023    /// Returns all the diagnostics intersecting the given range.
4024    pub fn diagnostics_in_range<'a, T, O>(
4025        &'a self,
4026        search_range: Range<T>,
4027        reversed: bool,
4028    ) -> impl 'a + Iterator<Item = DiagnosticEntry<O>>
4029    where
4030        T: 'a + Clone + ToOffset,
4031        O: 'a + FromAnchor,
4032    {
4033        let mut iterators: Vec<_> = self
4034            .diagnostics
4035            .iter()
4036            .map(|(_, collection)| {
4037                collection
4038                    .range::<T, text::Anchor>(search_range.clone(), self, true, reversed)
4039                    .peekable()
4040            })
4041            .collect();
4042
4043        std::iter::from_fn(move || {
4044            let (next_ix, _) = iterators
4045                .iter_mut()
4046                .enumerate()
4047                .flat_map(|(ix, iter)| Some((ix, iter.peek()?)))
4048                .min_by(|(_, a), (_, b)| {
4049                    let cmp = a
4050                        .range
4051                        .start
4052                        .cmp(&b.range.start, self)
4053                        // when range is equal, sort by diagnostic severity
4054                        .then(a.diagnostic.severity.cmp(&b.diagnostic.severity))
4055                        // and stabilize order with group_id
4056                        .then(a.diagnostic.group_id.cmp(&b.diagnostic.group_id));
4057                    if reversed {
4058                        cmp.reverse()
4059                    } else {
4060                        cmp
4061                    }
4062                })?;
4063            iterators[next_ix]
4064                .next()
4065                .map(|DiagnosticEntry { range, diagnostic }| DiagnosticEntry {
4066                    diagnostic,
4067                    range: FromAnchor::from_anchor(&range.start, self)
4068                        ..FromAnchor::from_anchor(&range.end, self),
4069                })
4070        })
4071    }
4072
4073    /// Returns all the diagnostic groups associated with the given
4074    /// language server ID. If no language server ID is provided,
4075    /// all diagnostics groups are returned.
4076    pub fn diagnostic_groups(
4077        &self,
4078        language_server_id: Option<LanguageServerId>,
4079    ) -> Vec<(LanguageServerId, DiagnosticGroup<Anchor>)> {
4080        let mut groups = Vec::new();
4081
4082        if let Some(language_server_id) = language_server_id {
4083            if let Ok(ix) = self
4084                .diagnostics
4085                .binary_search_by_key(&language_server_id, |e| e.0)
4086            {
4087                self.diagnostics[ix]
4088                    .1
4089                    .groups(language_server_id, &mut groups, self);
4090            }
4091        } else {
4092            for (language_server_id, diagnostics) in self.diagnostics.iter() {
4093                diagnostics.groups(*language_server_id, &mut groups, self);
4094            }
4095        }
4096
4097        groups.sort_by(|(id_a, group_a), (id_b, group_b)| {
4098            let a_start = &group_a.entries[group_a.primary_ix].range.start;
4099            let b_start = &group_b.entries[group_b.primary_ix].range.start;
4100            a_start.cmp(b_start, self).then_with(|| id_a.cmp(id_b))
4101        });
4102
4103        groups
4104    }
4105
4106    /// Returns an iterator over the diagnostics for the given group.
4107    pub fn diagnostic_group<O>(
4108        &self,
4109        group_id: usize,
4110    ) -> impl Iterator<Item = DiagnosticEntry<O>> + '_
4111    where
4112        O: FromAnchor + 'static,
4113    {
4114        self.diagnostics
4115            .iter()
4116            .flat_map(move |(_, set)| set.group(group_id, self))
4117    }
4118
4119    /// An integer version number that accounts for all updates besides
4120    /// the buffer's text itself (which is versioned via a version vector).
4121    pub fn non_text_state_update_count(&self) -> usize {
4122        self.non_text_state_update_count
4123    }
4124
4125    /// Returns a snapshot of underlying file.
4126    pub fn file(&self) -> Option<&Arc<dyn File>> {
4127        self.file.as_ref()
4128    }
4129
4130    /// Resolves the file path (relative to the worktree root) associated with the underlying file.
4131    pub fn resolve_file_path(&self, cx: &App, include_root: bool) -> Option<PathBuf> {
4132        if let Some(file) = self.file() {
4133            if file.path().file_name().is_none() || include_root {
4134                Some(file.full_path(cx))
4135            } else {
4136                Some(file.path().to_path_buf())
4137            }
4138        } else {
4139            None
4140        }
4141    }
4142}
4143
4144fn indent_size_for_line(text: &text::BufferSnapshot, row: u32) -> IndentSize {
4145    indent_size_for_text(text.chars_at(Point::new(row, 0)))
4146}
4147
4148fn indent_size_for_text(text: impl Iterator<Item = char>) -> IndentSize {
4149    let mut result = IndentSize::spaces(0);
4150    for c in text {
4151        let kind = match c {
4152            ' ' => IndentKind::Space,
4153            '\t' => IndentKind::Tab,
4154            _ => break,
4155        };
4156        if result.len == 0 {
4157            result.kind = kind;
4158        }
4159        result.len += 1;
4160    }
4161    result
4162}
4163
4164impl Clone for BufferSnapshot {
4165    fn clone(&self) -> Self {
4166        Self {
4167            text: self.text.clone(),
4168            syntax: self.syntax.clone(),
4169            file: self.file.clone(),
4170            remote_selections: self.remote_selections.clone(),
4171            diagnostics: self.diagnostics.clone(),
4172            language: self.language.clone(),
4173            non_text_state_update_count: self.non_text_state_update_count,
4174        }
4175    }
4176}
4177
4178impl Deref for BufferSnapshot {
4179    type Target = text::BufferSnapshot;
4180
4181    fn deref(&self) -> &Self::Target {
4182        &self.text
4183    }
4184}
4185
4186unsafe impl Send for BufferChunks<'_> {}
4187
4188impl<'a> BufferChunks<'a> {
4189    pub(crate) fn new(
4190        text: &'a Rope,
4191        range: Range<usize>,
4192        syntax: Option<(SyntaxMapCaptures<'a>, Vec<HighlightMap>)>,
4193        diagnostics: bool,
4194        buffer_snapshot: Option<&'a BufferSnapshot>,
4195    ) -> Self {
4196        let mut highlights = None;
4197        if let Some((captures, highlight_maps)) = syntax {
4198            highlights = Some(BufferChunkHighlights {
4199                captures,
4200                next_capture: None,
4201                stack: Default::default(),
4202                highlight_maps,
4203            })
4204        }
4205
4206        let diagnostic_endpoints = diagnostics.then(|| Vec::new().into_iter().peekable());
4207        let chunks = text.chunks_in_range(range.clone());
4208
4209        let mut this = BufferChunks {
4210            range,
4211            buffer_snapshot,
4212            chunks,
4213            diagnostic_endpoints,
4214            error_depth: 0,
4215            warning_depth: 0,
4216            information_depth: 0,
4217            hint_depth: 0,
4218            unnecessary_depth: 0,
4219            highlights,
4220        };
4221        this.initialize_diagnostic_endpoints();
4222        this
4223    }
4224
4225    /// Seeks to the given byte offset in the buffer.
4226    pub fn seek(&mut self, range: Range<usize>) {
4227        let old_range = std::mem::replace(&mut self.range, range.clone());
4228        self.chunks.set_range(self.range.clone());
4229        if let Some(highlights) = self.highlights.as_mut() {
4230            if old_range.start <= self.range.start && old_range.end >= self.range.end {
4231                // Reuse existing highlights stack, as the new range is a subrange of the old one.
4232                highlights
4233                    .stack
4234                    .retain(|(end_offset, _)| *end_offset > range.start);
4235                if let Some(capture) = &highlights.next_capture {
4236                    if range.start >= capture.node.start_byte() {
4237                        let next_capture_end = capture.node.end_byte();
4238                        if range.start < next_capture_end {
4239                            highlights.stack.push((
4240                                next_capture_end,
4241                                highlights.highlight_maps[capture.grammar_index].get(capture.index),
4242                            ));
4243                        }
4244                        highlights.next_capture.take();
4245                    }
4246                }
4247            } else if let Some(snapshot) = self.buffer_snapshot {
4248                let (captures, highlight_maps) = snapshot.get_highlights(self.range.clone());
4249                *highlights = BufferChunkHighlights {
4250                    captures,
4251                    next_capture: None,
4252                    stack: Default::default(),
4253                    highlight_maps,
4254                };
4255            } else {
4256                // We cannot obtain new highlights for a language-aware buffer iterator, as we don't have a buffer snapshot.
4257                // Seeking such BufferChunks is not supported.
4258                debug_assert!(false, "Attempted to seek on a language-aware buffer iterator without associated buffer snapshot");
4259            }
4260
4261            highlights.captures.set_byte_range(self.range.clone());
4262            self.initialize_diagnostic_endpoints();
4263        }
4264    }
4265
4266    fn initialize_diagnostic_endpoints(&mut self) {
4267        if let Some(diagnostics) = self.diagnostic_endpoints.as_mut() {
4268            if let Some(buffer) = self.buffer_snapshot {
4269                let mut diagnostic_endpoints = Vec::new();
4270                for entry in buffer.diagnostics_in_range::<_, usize>(self.range.clone(), false) {
4271                    diagnostic_endpoints.push(DiagnosticEndpoint {
4272                        offset: entry.range.start,
4273                        is_start: true,
4274                        severity: entry.diagnostic.severity,
4275                        is_unnecessary: entry.diagnostic.is_unnecessary,
4276                    });
4277                    diagnostic_endpoints.push(DiagnosticEndpoint {
4278                        offset: entry.range.end,
4279                        is_start: false,
4280                        severity: entry.diagnostic.severity,
4281                        is_unnecessary: entry.diagnostic.is_unnecessary,
4282                    });
4283                }
4284                diagnostic_endpoints
4285                    .sort_unstable_by_key(|endpoint| (endpoint.offset, !endpoint.is_start));
4286                *diagnostics = diagnostic_endpoints.into_iter().peekable();
4287                self.hint_depth = 0;
4288                self.error_depth = 0;
4289                self.warning_depth = 0;
4290                self.information_depth = 0;
4291            }
4292        }
4293    }
4294
4295    /// The current byte offset in the buffer.
4296    pub fn offset(&self) -> usize {
4297        self.range.start
4298    }
4299
4300    pub fn range(&self) -> Range<usize> {
4301        self.range.clone()
4302    }
4303
4304    fn update_diagnostic_depths(&mut self, endpoint: DiagnosticEndpoint) {
4305        let depth = match endpoint.severity {
4306            DiagnosticSeverity::ERROR => &mut self.error_depth,
4307            DiagnosticSeverity::WARNING => &mut self.warning_depth,
4308            DiagnosticSeverity::INFORMATION => &mut self.information_depth,
4309            DiagnosticSeverity::HINT => &mut self.hint_depth,
4310            _ => return,
4311        };
4312        if endpoint.is_start {
4313            *depth += 1;
4314        } else {
4315            *depth -= 1;
4316        }
4317
4318        if endpoint.is_unnecessary {
4319            if endpoint.is_start {
4320                self.unnecessary_depth += 1;
4321            } else {
4322                self.unnecessary_depth -= 1;
4323            }
4324        }
4325    }
4326
4327    fn current_diagnostic_severity(&self) -> Option<DiagnosticSeverity> {
4328        if self.error_depth > 0 {
4329            Some(DiagnosticSeverity::ERROR)
4330        } else if self.warning_depth > 0 {
4331            Some(DiagnosticSeverity::WARNING)
4332        } else if self.information_depth > 0 {
4333            Some(DiagnosticSeverity::INFORMATION)
4334        } else if self.hint_depth > 0 {
4335            Some(DiagnosticSeverity::HINT)
4336        } else {
4337            None
4338        }
4339    }
4340
4341    fn current_code_is_unnecessary(&self) -> bool {
4342        self.unnecessary_depth > 0
4343    }
4344}
4345
4346impl<'a> Iterator for BufferChunks<'a> {
4347    type Item = Chunk<'a>;
4348
4349    fn next(&mut self) -> Option<Self::Item> {
4350        let mut next_capture_start = usize::MAX;
4351        let mut next_diagnostic_endpoint = usize::MAX;
4352
4353        if let Some(highlights) = self.highlights.as_mut() {
4354            while let Some((parent_capture_end, _)) = highlights.stack.last() {
4355                if *parent_capture_end <= self.range.start {
4356                    highlights.stack.pop();
4357                } else {
4358                    break;
4359                }
4360            }
4361
4362            if highlights.next_capture.is_none() {
4363                highlights.next_capture = highlights.captures.next();
4364            }
4365
4366            while let Some(capture) = highlights.next_capture.as_ref() {
4367                if self.range.start < capture.node.start_byte() {
4368                    next_capture_start = capture.node.start_byte();
4369                    break;
4370                } else {
4371                    let highlight_id =
4372                        highlights.highlight_maps[capture.grammar_index].get(capture.index);
4373                    highlights
4374                        .stack
4375                        .push((capture.node.end_byte(), highlight_id));
4376                    highlights.next_capture = highlights.captures.next();
4377                }
4378            }
4379        }
4380
4381        let mut diagnostic_endpoints = std::mem::take(&mut self.diagnostic_endpoints);
4382        if let Some(diagnostic_endpoints) = diagnostic_endpoints.as_mut() {
4383            while let Some(endpoint) = diagnostic_endpoints.peek().copied() {
4384                if endpoint.offset <= self.range.start {
4385                    self.update_diagnostic_depths(endpoint);
4386                    diagnostic_endpoints.next();
4387                } else {
4388                    next_diagnostic_endpoint = endpoint.offset;
4389                    break;
4390                }
4391            }
4392        }
4393        self.diagnostic_endpoints = diagnostic_endpoints;
4394
4395        if let Some(chunk) = self.chunks.peek() {
4396            let chunk_start = self.range.start;
4397            let mut chunk_end = (self.chunks.offset() + chunk.len())
4398                .min(next_capture_start)
4399                .min(next_diagnostic_endpoint);
4400            let mut highlight_id = None;
4401            if let Some(highlights) = self.highlights.as_ref() {
4402                if let Some((parent_capture_end, parent_highlight_id)) = highlights.stack.last() {
4403                    chunk_end = chunk_end.min(*parent_capture_end);
4404                    highlight_id = Some(*parent_highlight_id);
4405                }
4406            }
4407
4408            let slice =
4409                &chunk[chunk_start - self.chunks.offset()..chunk_end - self.chunks.offset()];
4410            self.range.start = chunk_end;
4411            if self.range.start == self.chunks.offset() + chunk.len() {
4412                self.chunks.next().unwrap();
4413            }
4414
4415            Some(Chunk {
4416                text: slice,
4417                syntax_highlight_id: highlight_id,
4418                diagnostic_severity: self.current_diagnostic_severity(),
4419                is_unnecessary: self.current_code_is_unnecessary(),
4420                ..Default::default()
4421            })
4422        } else {
4423            None
4424        }
4425    }
4426}
4427
4428impl operation_queue::Operation for Operation {
4429    fn lamport_timestamp(&self) -> clock::Lamport {
4430        match self {
4431            Operation::Buffer(_) => {
4432                unreachable!("buffer operations should never be deferred at this layer")
4433            }
4434            Operation::UpdateDiagnostics {
4435                lamport_timestamp, ..
4436            }
4437            | Operation::UpdateSelections {
4438                lamport_timestamp, ..
4439            }
4440            | Operation::UpdateCompletionTriggers {
4441                lamport_timestamp, ..
4442            } => *lamport_timestamp,
4443        }
4444    }
4445}
4446
4447impl Default for Diagnostic {
4448    fn default() -> Self {
4449        Self {
4450            source: Default::default(),
4451            code: None,
4452            severity: DiagnosticSeverity::ERROR,
4453            message: Default::default(),
4454            group_id: 0,
4455            is_primary: false,
4456            is_disk_based: false,
4457            is_unnecessary: false,
4458            data: None,
4459        }
4460    }
4461}
4462
4463impl IndentSize {
4464    /// Returns an [`IndentSize`] representing the given spaces.
4465    pub fn spaces(len: u32) -> Self {
4466        Self {
4467            len,
4468            kind: IndentKind::Space,
4469        }
4470    }
4471
4472    /// Returns an [`IndentSize`] representing a tab.
4473    pub fn tab() -> Self {
4474        Self {
4475            len: 1,
4476            kind: IndentKind::Tab,
4477        }
4478    }
4479
4480    /// An iterator over the characters represented by this [`IndentSize`].
4481    pub fn chars(&self) -> impl Iterator<Item = char> {
4482        iter::repeat(self.char()).take(self.len as usize)
4483    }
4484
4485    /// The character representation of this [`IndentSize`].
4486    pub fn char(&self) -> char {
4487        match self.kind {
4488            IndentKind::Space => ' ',
4489            IndentKind::Tab => '\t',
4490        }
4491    }
4492
4493    /// Consumes the current [`IndentSize`] and returns a new one that has
4494    /// been shrunk or enlarged by the given size along the given direction.
4495    pub fn with_delta(mut self, direction: Ordering, size: IndentSize) -> Self {
4496        match direction {
4497            Ordering::Less => {
4498                if self.kind == size.kind && self.len >= size.len {
4499                    self.len -= size.len;
4500                }
4501            }
4502            Ordering::Equal => {}
4503            Ordering::Greater => {
4504                if self.len == 0 {
4505                    self = size;
4506                } else if self.kind == size.kind {
4507                    self.len += size.len;
4508                }
4509            }
4510        }
4511        self
4512    }
4513
4514    pub fn len_with_expanded_tabs(&self, tab_size: NonZeroU32) -> usize {
4515        match self.kind {
4516            IndentKind::Space => self.len as usize,
4517            IndentKind::Tab => self.len as usize * tab_size.get() as usize,
4518        }
4519    }
4520}
4521
4522#[cfg(any(test, feature = "test-support"))]
4523pub struct TestFile {
4524    pub path: Arc<Path>,
4525    pub root_name: String,
4526    pub local_root: Option<PathBuf>,
4527}
4528
4529#[cfg(any(test, feature = "test-support"))]
4530impl File for TestFile {
4531    fn path(&self) -> &Arc<Path> {
4532        &self.path
4533    }
4534
4535    fn full_path(&self, _: &gpui::App) -> PathBuf {
4536        PathBuf::from(&self.root_name).join(self.path.as_ref())
4537    }
4538
4539    fn as_local(&self) -> Option<&dyn LocalFile> {
4540        if self.local_root.is_some() {
4541            Some(self)
4542        } else {
4543            None
4544        }
4545    }
4546
4547    fn disk_state(&self) -> DiskState {
4548        unimplemented!()
4549    }
4550
4551    fn file_name<'a>(&'a self, _: &'a gpui::App) -> &'a std::ffi::OsStr {
4552        self.path().file_name().unwrap_or(self.root_name.as_ref())
4553    }
4554
4555    fn worktree_id(&self, _: &App) -> WorktreeId {
4556        WorktreeId::from_usize(0)
4557    }
4558
4559    fn as_any(&self) -> &dyn std::any::Any {
4560        unimplemented!()
4561    }
4562
4563    fn to_proto(&self, _: &App) -> rpc::proto::File {
4564        unimplemented!()
4565    }
4566
4567    fn is_private(&self) -> bool {
4568        false
4569    }
4570}
4571
4572#[cfg(any(test, feature = "test-support"))]
4573impl LocalFile for TestFile {
4574    fn abs_path(&self, _cx: &App) -> PathBuf {
4575        PathBuf::from(self.local_root.as_ref().unwrap())
4576            .join(&self.root_name)
4577            .join(self.path.as_ref())
4578    }
4579
4580    fn load(&self, _cx: &App) -> Task<Result<String>> {
4581        unimplemented!()
4582    }
4583
4584    fn load_bytes(&self, _cx: &App) -> Task<Result<Vec<u8>>> {
4585        unimplemented!()
4586    }
4587}
4588
4589pub(crate) fn contiguous_ranges(
4590    values: impl Iterator<Item = u32>,
4591    max_len: usize,
4592) -> impl Iterator<Item = Range<u32>> {
4593    let mut values = values;
4594    let mut current_range: Option<Range<u32>> = None;
4595    std::iter::from_fn(move || loop {
4596        if let Some(value) = values.next() {
4597            if let Some(range) = &mut current_range {
4598                if value == range.end && range.len() < max_len {
4599                    range.end += 1;
4600                    continue;
4601                }
4602            }
4603
4604            let prev_range = current_range.clone();
4605            current_range = Some(value..(value + 1));
4606            if prev_range.is_some() {
4607                return prev_range;
4608            }
4609        } else {
4610            return current_range.take();
4611        }
4612    })
4613}
4614
4615#[derive(Default, Debug)]
4616pub struct CharClassifier {
4617    scope: Option<LanguageScope>,
4618    for_completion: bool,
4619    ignore_punctuation: bool,
4620}
4621
4622impl CharClassifier {
4623    pub fn new(scope: Option<LanguageScope>) -> Self {
4624        Self {
4625            scope,
4626            for_completion: false,
4627            ignore_punctuation: false,
4628        }
4629    }
4630
4631    pub fn for_completion(self, for_completion: bool) -> Self {
4632        Self {
4633            for_completion,
4634            ..self
4635        }
4636    }
4637
4638    pub fn ignore_punctuation(self, ignore_punctuation: bool) -> Self {
4639        Self {
4640            ignore_punctuation,
4641            ..self
4642        }
4643    }
4644
4645    pub fn is_whitespace(&self, c: char) -> bool {
4646        self.kind(c) == CharKind::Whitespace
4647    }
4648
4649    pub fn is_word(&self, c: char) -> bool {
4650        self.kind(c) == CharKind::Word
4651    }
4652
4653    pub fn is_punctuation(&self, c: char) -> bool {
4654        self.kind(c) == CharKind::Punctuation
4655    }
4656
4657    pub fn kind_with(&self, c: char, ignore_punctuation: bool) -> CharKind {
4658        if c.is_whitespace() {
4659            return CharKind::Whitespace;
4660        } else if c.is_alphanumeric() || c == '_' {
4661            return CharKind::Word;
4662        }
4663
4664        if let Some(scope) = &self.scope {
4665            if let Some(characters) = scope.word_characters() {
4666                if characters.contains(&c) {
4667                    if c == '-' && !self.for_completion && !ignore_punctuation {
4668                        return CharKind::Punctuation;
4669                    }
4670                    return CharKind::Word;
4671                }
4672            }
4673        }
4674
4675        if ignore_punctuation {
4676            CharKind::Word
4677        } else {
4678            CharKind::Punctuation
4679        }
4680    }
4681
4682    pub fn kind(&self, c: char) -> CharKind {
4683        self.kind_with(c, self.ignore_punctuation)
4684    }
4685}
4686
4687/// Find all of the ranges of whitespace that occur at the ends of lines
4688/// in the given rope.
4689///
4690/// This could also be done with a regex search, but this implementation
4691/// avoids copying text.
4692pub fn trailing_whitespace_ranges(rope: &Rope) -> Vec<Range<usize>> {
4693    let mut ranges = Vec::new();
4694
4695    let mut offset = 0;
4696    let mut prev_chunk_trailing_whitespace_range = 0..0;
4697    for chunk in rope.chunks() {
4698        let mut prev_line_trailing_whitespace_range = 0..0;
4699        for (i, line) in chunk.split('\n').enumerate() {
4700            let line_end_offset = offset + line.len();
4701            let trimmed_line_len = line.trim_end_matches([' ', '\t']).len();
4702            let mut trailing_whitespace_range = (offset + trimmed_line_len)..line_end_offset;
4703
4704            if i == 0 && trimmed_line_len == 0 {
4705                trailing_whitespace_range.start = prev_chunk_trailing_whitespace_range.start;
4706            }
4707            if !prev_line_trailing_whitespace_range.is_empty() {
4708                ranges.push(prev_line_trailing_whitespace_range);
4709            }
4710
4711            offset = line_end_offset + 1;
4712            prev_line_trailing_whitespace_range = trailing_whitespace_range;
4713        }
4714
4715        offset -= 1;
4716        prev_chunk_trailing_whitespace_range = prev_line_trailing_whitespace_range;
4717    }
4718
4719    if !prev_chunk_trailing_whitespace_range.is_empty() {
4720        ranges.push(prev_chunk_trailing_whitespace_range);
4721    }
4722
4723    ranges
4724}