lib.rs

   1pub mod display_map;
   2mod element;
   3pub mod movement;
   4
   5#[cfg(test)]
   6mod test;
   7
   8use buffer::rope::TextDimension;
   9use clock::ReplicaId;
  10pub use display_map::DisplayPoint;
  11use display_map::*;
  12pub use element::*;
  13use gpui::{
  14    action,
  15    geometry::vector::{vec2f, Vector2F},
  16    keymap::Binding,
  17    text_layout, AppContext, ClipboardItem, Element, ElementBox, Entity, ModelHandle,
  18    MutableAppContext, RenderContext, View, ViewContext, WeakViewHandle,
  19};
  20use language::*;
  21use serde::{Deserialize, Serialize};
  22use smallvec::SmallVec;
  23use smol::Timer;
  24use std::{
  25    cell::RefCell,
  26    cmp::{self, Ordering},
  27    collections::HashSet,
  28    iter, mem,
  29    ops::{Range, RangeInclusive},
  30    rc::Rc,
  31    sync::Arc,
  32    time::Duration,
  33};
  34use sum_tree::Bias;
  35use theme::{EditorStyle, SyntaxTheme};
  36use util::post_inc;
  37
  38const CURSOR_BLINK_INTERVAL: Duration = Duration::from_millis(500);
  39const MAX_LINE_LEN: usize = 1024;
  40
  41action!(Cancel);
  42action!(Backspace);
  43action!(Delete);
  44action!(Input, String);
  45action!(Newline);
  46action!(Tab);
  47action!(DeleteLine);
  48action!(DeleteToPreviousWordBoundary);
  49action!(DeleteToNextWordBoundary);
  50action!(DeleteToBeginningOfLine);
  51action!(DeleteToEndOfLine);
  52action!(CutToEndOfLine);
  53action!(DuplicateLine);
  54action!(MoveLineUp);
  55action!(MoveLineDown);
  56action!(Cut);
  57action!(Copy);
  58action!(Paste);
  59action!(Undo);
  60action!(Redo);
  61action!(MoveUp);
  62action!(MoveDown);
  63action!(MoveLeft);
  64action!(MoveRight);
  65action!(MoveToPreviousWordBoundary);
  66action!(MoveToNextWordBoundary);
  67action!(MoveToBeginningOfLine);
  68action!(MoveToEndOfLine);
  69action!(MoveToBeginning);
  70action!(MoveToEnd);
  71action!(SelectUp);
  72action!(SelectDown);
  73action!(SelectLeft);
  74action!(SelectRight);
  75action!(SelectToPreviousWordBoundary);
  76action!(SelectToNextWordBoundary);
  77action!(SelectToBeginningOfLine, bool);
  78action!(SelectToEndOfLine);
  79action!(SelectToBeginning);
  80action!(SelectToEnd);
  81action!(SelectAll);
  82action!(SelectLine);
  83action!(SplitSelectionIntoLines);
  84action!(AddSelectionAbove);
  85action!(AddSelectionBelow);
  86action!(SelectLargerSyntaxNode);
  87action!(SelectSmallerSyntaxNode);
  88action!(MoveToEnclosingBracket);
  89action!(ShowNextDiagnostic);
  90action!(PageUp);
  91action!(PageDown);
  92action!(Fold);
  93action!(Unfold);
  94action!(FoldSelectedRanges);
  95action!(Scroll, Vector2F);
  96action!(Select, SelectPhase);
  97
  98pub fn init(cx: &mut MutableAppContext) {
  99    cx.add_bindings(vec![
 100        Binding::new("escape", Cancel, Some("Editor")),
 101        Binding::new("backspace", Backspace, Some("Editor")),
 102        Binding::new("ctrl-h", Backspace, Some("Editor")),
 103        Binding::new("delete", Delete, Some("Editor")),
 104        Binding::new("ctrl-d", Delete, Some("Editor")),
 105        Binding::new("enter", Newline, Some("Editor && mode == full")),
 106        Binding::new(
 107            "alt-enter",
 108            Input("\n".into()),
 109            Some("Editor && mode == auto_height"),
 110        ),
 111        Binding::new("tab", Tab, Some("Editor")),
 112        Binding::new("ctrl-shift-K", DeleteLine, Some("Editor")),
 113        Binding::new(
 114            "alt-backspace",
 115            DeleteToPreviousWordBoundary,
 116            Some("Editor"),
 117        ),
 118        Binding::new("alt-h", DeleteToPreviousWordBoundary, Some("Editor")),
 119        Binding::new("alt-delete", DeleteToNextWordBoundary, Some("Editor")),
 120        Binding::new("alt-d", DeleteToNextWordBoundary, Some("Editor")),
 121        Binding::new("cmd-backspace", DeleteToBeginningOfLine, Some("Editor")),
 122        Binding::new("cmd-delete", DeleteToEndOfLine, Some("Editor")),
 123        Binding::new("ctrl-k", CutToEndOfLine, Some("Editor")),
 124        Binding::new("cmd-shift-D", DuplicateLine, Some("Editor")),
 125        Binding::new("ctrl-cmd-up", MoveLineUp, Some("Editor")),
 126        Binding::new("ctrl-cmd-down", MoveLineDown, Some("Editor")),
 127        Binding::new("cmd-x", Cut, Some("Editor")),
 128        Binding::new("cmd-c", Copy, Some("Editor")),
 129        Binding::new("cmd-v", Paste, Some("Editor")),
 130        Binding::new("cmd-z", Undo, Some("Editor")),
 131        Binding::new("cmd-shift-Z", Redo, Some("Editor")),
 132        Binding::new("up", MoveUp, Some("Editor")),
 133        Binding::new("down", MoveDown, Some("Editor")),
 134        Binding::new("left", MoveLeft, Some("Editor")),
 135        Binding::new("right", MoveRight, Some("Editor")),
 136        Binding::new("ctrl-p", MoveUp, Some("Editor")),
 137        Binding::new("ctrl-n", MoveDown, Some("Editor")),
 138        Binding::new("ctrl-b", MoveLeft, Some("Editor")),
 139        Binding::new("ctrl-f", MoveRight, Some("Editor")),
 140        Binding::new("alt-left", MoveToPreviousWordBoundary, Some("Editor")),
 141        Binding::new("alt-b", MoveToPreviousWordBoundary, Some("Editor")),
 142        Binding::new("alt-right", MoveToNextWordBoundary, Some("Editor")),
 143        Binding::new("alt-f", MoveToNextWordBoundary, Some("Editor")),
 144        Binding::new("cmd-left", MoveToBeginningOfLine, Some("Editor")),
 145        Binding::new("ctrl-a", MoveToBeginningOfLine, Some("Editor")),
 146        Binding::new("cmd-right", MoveToEndOfLine, Some("Editor")),
 147        Binding::new("ctrl-e", MoveToEndOfLine, Some("Editor")),
 148        Binding::new("cmd-up", MoveToBeginning, Some("Editor")),
 149        Binding::new("cmd-down", MoveToEnd, Some("Editor")),
 150        Binding::new("shift-up", SelectUp, Some("Editor")),
 151        Binding::new("ctrl-shift-P", SelectUp, Some("Editor")),
 152        Binding::new("shift-down", SelectDown, Some("Editor")),
 153        Binding::new("ctrl-shift-N", SelectDown, Some("Editor")),
 154        Binding::new("shift-left", SelectLeft, Some("Editor")),
 155        Binding::new("ctrl-shift-B", SelectLeft, Some("Editor")),
 156        Binding::new("shift-right", SelectRight, Some("Editor")),
 157        Binding::new("ctrl-shift-F", SelectRight, Some("Editor")),
 158        Binding::new(
 159            "alt-shift-left",
 160            SelectToPreviousWordBoundary,
 161            Some("Editor"),
 162        ),
 163        Binding::new("alt-shift-B", SelectToPreviousWordBoundary, Some("Editor")),
 164        Binding::new("alt-shift-right", SelectToNextWordBoundary, Some("Editor")),
 165        Binding::new("alt-shift-F", SelectToNextWordBoundary, Some("Editor")),
 166        Binding::new(
 167            "cmd-shift-left",
 168            SelectToBeginningOfLine(true),
 169            Some("Editor"),
 170        ),
 171        Binding::new(
 172            "ctrl-shift-A",
 173            SelectToBeginningOfLine(true),
 174            Some("Editor"),
 175        ),
 176        Binding::new("cmd-shift-right", SelectToEndOfLine, Some("Editor")),
 177        Binding::new("ctrl-shift-E", SelectToEndOfLine, Some("Editor")),
 178        Binding::new("cmd-shift-up", SelectToBeginning, Some("Editor")),
 179        Binding::new("cmd-shift-down", SelectToEnd, Some("Editor")),
 180        Binding::new("cmd-a", SelectAll, Some("Editor")),
 181        Binding::new("cmd-l", SelectLine, Some("Editor")),
 182        Binding::new("cmd-shift-L", SplitSelectionIntoLines, Some("Editor")),
 183        Binding::new("cmd-alt-up", AddSelectionAbove, Some("Editor")),
 184        Binding::new("cmd-ctrl-p", AddSelectionAbove, Some("Editor")),
 185        Binding::new("cmd-alt-down", AddSelectionBelow, Some("Editor")),
 186        Binding::new("cmd-ctrl-n", AddSelectionBelow, Some("Editor")),
 187        Binding::new("alt-up", SelectLargerSyntaxNode, Some("Editor")),
 188        Binding::new("ctrl-w", SelectLargerSyntaxNode, Some("Editor")),
 189        Binding::new("alt-down", SelectSmallerSyntaxNode, Some("Editor")),
 190        Binding::new("ctrl-shift-W", SelectSmallerSyntaxNode, Some("Editor")),
 191        Binding::new("ctrl-.", ShowNextDiagnostic, Some("Editor")),
 192        Binding::new("ctrl-m", MoveToEnclosingBracket, Some("Editor")),
 193        Binding::new("pageup", PageUp, Some("Editor")),
 194        Binding::new("pagedown", PageDown, Some("Editor")),
 195        Binding::new("alt-cmd-[", Fold, Some("Editor")),
 196        Binding::new("alt-cmd-]", Unfold, Some("Editor")),
 197        Binding::new("alt-cmd-f", FoldSelectedRanges, Some("Editor")),
 198    ]);
 199
 200    cx.add_action(|this: &mut Editor, action: &Scroll, cx| this.set_scroll_position(action.0, cx));
 201    cx.add_action(Editor::select);
 202    cx.add_action(Editor::cancel);
 203    cx.add_action(Editor::handle_input);
 204    cx.add_action(Editor::newline);
 205    cx.add_action(Editor::backspace);
 206    cx.add_action(Editor::delete);
 207    cx.add_action(Editor::tab);
 208    cx.add_action(Editor::delete_line);
 209    cx.add_action(Editor::delete_to_previous_word_boundary);
 210    cx.add_action(Editor::delete_to_next_word_boundary);
 211    cx.add_action(Editor::delete_to_beginning_of_line);
 212    cx.add_action(Editor::delete_to_end_of_line);
 213    cx.add_action(Editor::cut_to_end_of_line);
 214    cx.add_action(Editor::duplicate_line);
 215    cx.add_action(Editor::move_line_up);
 216    cx.add_action(Editor::move_line_down);
 217    cx.add_action(Editor::cut);
 218    cx.add_action(Editor::copy);
 219    cx.add_action(Editor::paste);
 220    cx.add_action(Editor::undo);
 221    cx.add_action(Editor::redo);
 222    cx.add_action(Editor::move_up);
 223    cx.add_action(Editor::move_down);
 224    cx.add_action(Editor::move_left);
 225    cx.add_action(Editor::move_right);
 226    cx.add_action(Editor::move_to_previous_word_boundary);
 227    cx.add_action(Editor::move_to_next_word_boundary);
 228    cx.add_action(Editor::move_to_beginning_of_line);
 229    cx.add_action(Editor::move_to_end_of_line);
 230    cx.add_action(Editor::move_to_beginning);
 231    cx.add_action(Editor::move_to_end);
 232    cx.add_action(Editor::select_up);
 233    cx.add_action(Editor::select_down);
 234    cx.add_action(Editor::select_left);
 235    cx.add_action(Editor::select_right);
 236    cx.add_action(Editor::select_to_previous_word_boundary);
 237    cx.add_action(Editor::select_to_next_word_boundary);
 238    cx.add_action(Editor::select_to_beginning_of_line);
 239    cx.add_action(Editor::select_to_end_of_line);
 240    cx.add_action(Editor::select_to_beginning);
 241    cx.add_action(Editor::select_to_end);
 242    cx.add_action(Editor::select_all);
 243    cx.add_action(Editor::select_line);
 244    cx.add_action(Editor::split_selection_into_lines);
 245    cx.add_action(Editor::add_selection_above);
 246    cx.add_action(Editor::add_selection_below);
 247    cx.add_action(Editor::select_larger_syntax_node);
 248    cx.add_action(Editor::select_smaller_syntax_node);
 249    cx.add_action(Editor::move_to_enclosing_bracket);
 250    cx.add_action(Editor::show_next_diagnostic);
 251    cx.add_action(Editor::page_up);
 252    cx.add_action(Editor::page_down);
 253    cx.add_action(Editor::fold);
 254    cx.add_action(Editor::unfold);
 255    cx.add_action(Editor::fold_selected_ranges);
 256}
 257
 258trait SelectionExt {
 259    fn display_range(&self, map: &DisplayMapSnapshot) -> Range<DisplayPoint>;
 260    fn spanned_rows(
 261        &self,
 262        include_end_if_at_line_start: bool,
 263        map: &DisplayMapSnapshot,
 264    ) -> SpannedRows;
 265}
 266
 267struct SpannedRows {
 268    buffer_rows: Range<u32>,
 269    display_rows: Range<u32>,
 270}
 271
 272#[derive(Clone, Debug)]
 273pub enum SelectPhase {
 274    Begin {
 275        position: DisplayPoint,
 276        add: bool,
 277    },
 278    Update {
 279        position: DisplayPoint,
 280        scroll_position: Vector2F,
 281    },
 282    End,
 283}
 284
 285#[derive(Copy, Clone, PartialEq, Eq)]
 286pub enum EditorMode {
 287    SingleLine,
 288    AutoHeight { max_lines: usize },
 289    Full,
 290}
 291
 292#[derive(Clone)]
 293pub struct EditorSettings {
 294    pub tab_size: usize,
 295    pub style: EditorStyle,
 296}
 297
 298pub struct Editor {
 299    handle: WeakViewHandle<Self>,
 300    buffer: ModelHandle<Buffer>,
 301    display_map: ModelHandle<DisplayMap>,
 302    selection_set_id: SelectionSetId,
 303    pending_selection: Option<Selection<Anchor>>,
 304    next_selection_id: usize,
 305    add_selections_state: Option<AddSelectionsState>,
 306    autoclose_stack: Vec<BracketPairState>,
 307    select_larger_syntax_node_stack: Vec<Box<[Selection<usize>]>>,
 308    active_diagnostics: Option<ActiveDiagnosticGroup>,
 309    scroll_position: Vector2F,
 310    scroll_top_anchor: Anchor,
 311    autoscroll_requested: bool,
 312    build_settings: Rc<RefCell<dyn Fn(&AppContext) -> EditorSettings>>,
 313    focused: bool,
 314    show_local_cursors: bool,
 315    blink_epoch: usize,
 316    blinking_paused: bool,
 317    mode: EditorMode,
 318    placeholder_text: Option<Arc<str>>,
 319}
 320
 321pub struct Snapshot {
 322    pub mode: EditorMode,
 323    pub display_snapshot: DisplayMapSnapshot,
 324    pub placeholder_text: Option<Arc<str>>,
 325    is_focused: bool,
 326    scroll_position: Vector2F,
 327    scroll_top_anchor: Anchor,
 328}
 329
 330struct AddSelectionsState {
 331    above: bool,
 332    stack: Vec<usize>,
 333}
 334
 335#[derive(Debug)]
 336struct BracketPairState {
 337    ranges: AnchorRangeSet,
 338    pair: BracketPair,
 339}
 340
 341#[derive(Debug)]
 342struct ActiveDiagnosticGroup {
 343    primary_range: Range<Anchor>,
 344    block_ids: HashSet<BlockId>,
 345}
 346
 347#[derive(Serialize, Deserialize)]
 348struct ClipboardSelection {
 349    len: usize,
 350    is_entire_line: bool,
 351}
 352
 353impl Editor {
 354    pub fn single_line(
 355        build_settings: impl 'static + Fn(&AppContext) -> EditorSettings,
 356        cx: &mut ViewContext<Self>,
 357    ) -> Self {
 358        let buffer = cx.add_model(|cx| Buffer::new(0, String::new(), cx));
 359        let mut view = Self::for_buffer(buffer, build_settings, cx);
 360        view.mode = EditorMode::SingleLine;
 361        view
 362    }
 363
 364    pub fn auto_height(
 365        max_lines: usize,
 366        build_settings: impl 'static + Fn(&AppContext) -> EditorSettings,
 367        cx: &mut ViewContext<Self>,
 368    ) -> Self {
 369        let buffer = cx.add_model(|cx| Buffer::new(0, String::new(), cx));
 370        let mut view = Self::for_buffer(buffer, build_settings, cx);
 371        view.mode = EditorMode::AutoHeight { max_lines };
 372        view
 373    }
 374
 375    pub fn for_buffer(
 376        buffer: ModelHandle<Buffer>,
 377        build_settings: impl 'static + Fn(&AppContext) -> EditorSettings,
 378        cx: &mut ViewContext<Self>,
 379    ) -> Self {
 380        Self::new(buffer, Rc::new(RefCell::new(build_settings)), cx)
 381    }
 382
 383    pub fn clone(&self, cx: &mut ViewContext<Self>) -> Self {
 384        let mut clone = Self::new(self.buffer.clone(), self.build_settings.clone(), cx);
 385        clone.scroll_position = self.scroll_position;
 386        clone.scroll_top_anchor = self.scroll_top_anchor.clone();
 387        clone
 388    }
 389
 390    pub fn new(
 391        buffer: ModelHandle<Buffer>,
 392        build_settings: Rc<RefCell<dyn Fn(&AppContext) -> EditorSettings>>,
 393        cx: &mut ViewContext<Self>,
 394    ) -> Self {
 395        let settings = build_settings.borrow_mut()(cx);
 396        let display_map = cx.add_model(|cx| {
 397            DisplayMap::new(
 398                buffer.clone(),
 399                settings.tab_size,
 400                settings.style.text.font_id,
 401                settings.style.text.font_size,
 402                None,
 403                cx,
 404            )
 405        });
 406        cx.observe(&buffer, Self::on_buffer_changed).detach();
 407        cx.subscribe(&buffer, Self::on_buffer_event).detach();
 408        cx.observe(&display_map, Self::on_display_map_changed)
 409            .detach();
 410
 411        let mut next_selection_id = 0;
 412        let selection_set_id = buffer.update(cx, |buffer, cx| {
 413            buffer.add_selection_set(
 414                &[Selection {
 415                    id: post_inc(&mut next_selection_id),
 416                    start: 0,
 417                    end: 0,
 418                    reversed: false,
 419                    goal: SelectionGoal::None,
 420                }],
 421                cx,
 422            )
 423        });
 424        Self {
 425            handle: cx.handle().downgrade(),
 426            buffer,
 427            display_map,
 428            selection_set_id,
 429            pending_selection: None,
 430            next_selection_id,
 431            add_selections_state: None,
 432            autoclose_stack: Default::default(),
 433            select_larger_syntax_node_stack: Vec::new(),
 434            active_diagnostics: None,
 435            build_settings,
 436            scroll_position: Vector2F::zero(),
 437            scroll_top_anchor: Anchor::min(),
 438            autoscroll_requested: false,
 439            focused: false,
 440            show_local_cursors: false,
 441            blink_epoch: 0,
 442            blinking_paused: false,
 443            mode: EditorMode::Full,
 444            placeholder_text: None,
 445        }
 446    }
 447
 448    pub fn replica_id(&self, cx: &AppContext) -> ReplicaId {
 449        self.buffer.read(cx).replica_id()
 450    }
 451
 452    pub fn buffer(&self) -> &ModelHandle<Buffer> {
 453        &self.buffer
 454    }
 455
 456    pub fn snapshot(&mut self, cx: &mut MutableAppContext) -> Snapshot {
 457        Snapshot {
 458            mode: self.mode,
 459            display_snapshot: self.display_map.update(cx, |map, cx| map.snapshot(cx)),
 460            scroll_position: self.scroll_position,
 461            scroll_top_anchor: self.scroll_top_anchor.clone(),
 462            placeholder_text: self.placeholder_text.clone(),
 463            is_focused: self
 464                .handle
 465                .upgrade(cx)
 466                .map_or(false, |handle| handle.is_focused(cx)),
 467        }
 468    }
 469
 470    pub fn language<'a>(&self, cx: &'a AppContext) -> Option<&'a Arc<Language>> {
 471        self.buffer.read(cx).language()
 472    }
 473
 474    pub fn set_placeholder_text(
 475        &mut self,
 476        placeholder_text: impl Into<Arc<str>>,
 477        cx: &mut ViewContext<Self>,
 478    ) {
 479        self.placeholder_text = Some(placeholder_text.into());
 480        cx.notify();
 481    }
 482
 483    fn set_scroll_position(&mut self, scroll_position: Vector2F, cx: &mut ViewContext<Self>) {
 484        let map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 485        let scroll_top_buffer_offset =
 486            DisplayPoint::new(scroll_position.y() as u32, 0).to_offset(&map, Bias::Right);
 487        self.scroll_top_anchor = self
 488            .buffer
 489            .read(cx)
 490            .anchor_at(scroll_top_buffer_offset, Bias::Right);
 491        self.scroll_position = vec2f(
 492            scroll_position.x(),
 493            scroll_position.y() - self.scroll_top_anchor.to_display_point(&map).row() as f32,
 494        );
 495
 496        debug_assert_eq!(
 497            compute_scroll_position(&map, self.scroll_position, &self.scroll_top_anchor),
 498            scroll_position
 499        );
 500
 501        cx.notify();
 502    }
 503
 504    pub fn clamp_scroll_left(&mut self, max: f32) -> bool {
 505        if max < self.scroll_position.x() {
 506            self.scroll_position.set_x(max);
 507            true
 508        } else {
 509            false
 510        }
 511    }
 512
 513    pub fn autoscroll_vertically(
 514        &mut self,
 515        viewport_height: f32,
 516        line_height: f32,
 517        cx: &mut ViewContext<Self>,
 518    ) -> bool {
 519        let visible_lines = viewport_height / line_height;
 520        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 521        let mut scroll_position =
 522            compute_scroll_position(&display_map, self.scroll_position, &self.scroll_top_anchor);
 523        let max_scroll_top = if matches!(self.mode, EditorMode::AutoHeight { .. }) {
 524            (display_map.max_point().row() as f32 - visible_lines + 1.).max(0.)
 525        } else {
 526            display_map.max_point().row().saturating_sub(1) as f32
 527        };
 528        if scroll_position.y() > max_scroll_top {
 529            scroll_position.set_y(max_scroll_top);
 530            self.set_scroll_position(scroll_position, cx);
 531        }
 532
 533        if self.autoscroll_requested {
 534            self.autoscroll_requested = false;
 535        } else {
 536            return false;
 537        }
 538
 539        let mut selections = self.selections::<Point>(cx).peekable();
 540        let first_cursor_top = selections
 541            .peek()
 542            .unwrap()
 543            .head()
 544            .to_display_point(&display_map)
 545            .row() as f32;
 546        let last_cursor_bottom = selections
 547            .last()
 548            .unwrap()
 549            .head()
 550            .to_display_point(&display_map)
 551            .row() as f32
 552            + 1.0;
 553
 554        let margin = if matches!(self.mode, EditorMode::AutoHeight { .. }) {
 555            0.
 556        } else {
 557            ((visible_lines - (last_cursor_bottom - first_cursor_top)) / 2.0)
 558                .floor()
 559                .min(3.0)
 560        };
 561        if margin < 0.0 {
 562            return false;
 563        }
 564
 565        let target_top = (first_cursor_top - margin).max(0.0);
 566        let target_bottom = last_cursor_bottom + margin;
 567        let start_row = scroll_position.y();
 568        let end_row = start_row + visible_lines;
 569
 570        if target_top < start_row {
 571            scroll_position.set_y(target_top);
 572            self.set_scroll_position(scroll_position, cx);
 573        } else if target_bottom >= end_row {
 574            scroll_position.set_y(target_bottom - visible_lines);
 575            self.set_scroll_position(scroll_position, cx);
 576        }
 577
 578        true
 579    }
 580
 581    pub fn autoscroll_horizontally(
 582        &mut self,
 583        start_row: u32,
 584        viewport_width: f32,
 585        scroll_width: f32,
 586        max_glyph_width: f32,
 587        layouts: &[text_layout::Line],
 588        cx: &mut ViewContext<Self>,
 589    ) -> bool {
 590        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 591        let selections = self.selections::<Point>(cx);
 592        let mut target_left = std::f32::INFINITY;
 593        let mut target_right = 0.0_f32;
 594        for selection in selections {
 595            let head = selection.head().to_display_point(&display_map);
 596            let start_column = head.column().saturating_sub(3);
 597            let end_column = cmp::min(display_map.line_len(head.row()), head.column() + 3);
 598            target_left = target_left
 599                .min(layouts[(head.row() - start_row) as usize].x_for_index(start_column as usize));
 600            target_right = target_right.max(
 601                layouts[(head.row() - start_row) as usize].x_for_index(end_column as usize)
 602                    + max_glyph_width,
 603            );
 604        }
 605        target_right = target_right.min(scroll_width);
 606
 607        if target_right - target_left > viewport_width {
 608            return false;
 609        }
 610
 611        let scroll_left = self.scroll_position.x() * max_glyph_width;
 612        let scroll_right = scroll_left + viewport_width;
 613
 614        if target_left < scroll_left {
 615            self.scroll_position.set_x(target_left / max_glyph_width);
 616            true
 617        } else if target_right > scroll_right {
 618            self.scroll_position
 619                .set_x((target_right - viewport_width) / max_glyph_width);
 620            true
 621        } else {
 622            false
 623        }
 624    }
 625
 626    fn select(&mut self, Select(phase): &Select, cx: &mut ViewContext<Self>) {
 627        match phase {
 628            SelectPhase::Begin { position, add } => self.begin_selection(*position, *add, cx),
 629            SelectPhase::Update {
 630                position,
 631                scroll_position,
 632            } => self.update_selection(*position, *scroll_position, cx),
 633            SelectPhase::End => self.end_selection(cx),
 634        }
 635    }
 636
 637    fn begin_selection(&mut self, position: DisplayPoint, add: bool, cx: &mut ViewContext<Self>) {
 638        if !self.focused {
 639            cx.focus_self();
 640            cx.emit(Event::Activate);
 641        }
 642
 643        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 644        let buffer = self.buffer.read(cx);
 645        let cursor = buffer.anchor_before(position.to_point(&display_map));
 646        let selection = Selection {
 647            id: post_inc(&mut self.next_selection_id),
 648            start: cursor.clone(),
 649            end: cursor,
 650            reversed: false,
 651            goal: SelectionGoal::None,
 652        };
 653
 654        if !add {
 655            self.update_selections::<usize>(Vec::new(), false, cx);
 656        }
 657        self.pending_selection = Some(selection);
 658
 659        cx.notify();
 660    }
 661
 662    fn update_selection(
 663        &mut self,
 664        position: DisplayPoint,
 665        scroll_position: Vector2F,
 666        cx: &mut ViewContext<Self>,
 667    ) {
 668        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 669        if let Some(pending_selection) = self.pending_selection.as_mut() {
 670            let buffer = self.buffer.read(cx);
 671            let cursor = buffer.anchor_before(position.to_point(&display_map));
 672            if cursor.cmp(&pending_selection.tail(), buffer).unwrap() < Ordering::Equal {
 673                if !pending_selection.reversed {
 674                    pending_selection.end = pending_selection.start.clone();
 675                    pending_selection.reversed = true;
 676                }
 677                pending_selection.start = cursor;
 678            } else {
 679                if pending_selection.reversed {
 680                    pending_selection.start = pending_selection.end.clone();
 681                    pending_selection.reversed = false;
 682                }
 683                pending_selection.end = cursor;
 684            }
 685        } else {
 686            log::error!("update_selection dispatched with no pending selection");
 687            return;
 688        }
 689
 690        self.set_scroll_position(scroll_position, cx);
 691        cx.notify();
 692    }
 693
 694    fn end_selection(&mut self, cx: &mut ViewContext<Self>) {
 695        if self.pending_selection.is_some() {
 696            let selections = self.selections::<usize>(cx).collect::<Vec<_>>();
 697            self.update_selections(selections, false, cx);
 698        }
 699    }
 700
 701    pub fn is_selecting(&self) -> bool {
 702        self.pending_selection.is_some()
 703    }
 704
 705    pub fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
 706        if let Some(pending_selection) = self.pending_selection.take() {
 707            let buffer = self.buffer.read(cx);
 708            let pending_selection = Selection {
 709                id: pending_selection.id,
 710                start: pending_selection.start.to_point(buffer),
 711                end: pending_selection.end.to_point(buffer),
 712                reversed: pending_selection.reversed,
 713                goal: pending_selection.goal,
 714            };
 715            if self.selections::<Point>(cx).next().is_none() {
 716                self.update_selections(vec![pending_selection], true, cx);
 717            }
 718        } else {
 719            let mut oldest_selection = self.oldest_selection::<usize>(cx);
 720            if self.selection_count(cx) == 1 {
 721                oldest_selection.start = oldest_selection.head().clone();
 722                oldest_selection.end = oldest_selection.head().clone();
 723            }
 724            self.update_selections(vec![oldest_selection], true, cx);
 725        }
 726    }
 727
 728    fn select_ranges<I, T>(&mut self, ranges: I, autoscroll: bool, cx: &mut ViewContext<Self>)
 729    where
 730        I: IntoIterator<Item = Range<T>>,
 731        T: ToOffset,
 732    {
 733        let buffer = self.buffer.read(cx);
 734        let selections = ranges
 735            .into_iter()
 736            .map(|range| {
 737                let mut start = range.start.to_offset(buffer);
 738                let mut end = range.end.to_offset(buffer);
 739                let reversed = if start > end {
 740                    mem::swap(&mut start, &mut end);
 741                    true
 742                } else {
 743                    false
 744                };
 745                Selection {
 746                    id: post_inc(&mut self.next_selection_id),
 747                    start: start,
 748                    end: end,
 749                    reversed,
 750                    goal: SelectionGoal::None,
 751                }
 752            })
 753            .collect();
 754        self.update_selections(selections, autoscroll, cx);
 755    }
 756
 757    #[cfg(test)]
 758    fn select_display_ranges<'a, T>(
 759        &mut self,
 760        ranges: T,
 761        cx: &mut ViewContext<Self>,
 762    ) -> anyhow::Result<()>
 763    where
 764        T: IntoIterator<Item = &'a Range<DisplayPoint>>,
 765    {
 766        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 767        let selections = ranges
 768            .into_iter()
 769            .map(|range| {
 770                let mut start = range.start;
 771                let mut end = range.end;
 772                let reversed = if start > end {
 773                    mem::swap(&mut start, &mut end);
 774                    true
 775                } else {
 776                    false
 777                };
 778                Selection {
 779                    id: post_inc(&mut self.next_selection_id),
 780                    start: start.to_point(&display_map),
 781                    end: end.to_point(&display_map),
 782                    reversed,
 783                    goal: SelectionGoal::None,
 784                }
 785            })
 786            .collect();
 787        self.update_selections(selections, false, cx);
 788        Ok(())
 789    }
 790
 791    pub fn handle_input(&mut self, action: &Input, cx: &mut ViewContext<Self>) {
 792        let text = action.0.as_ref();
 793        if !self.skip_autoclose_end(text, cx) {
 794            self.start_transaction(cx);
 795            self.insert(text, cx);
 796            self.autoclose_pairs(cx);
 797            self.end_transaction(cx);
 798        }
 799    }
 800
 801    pub fn newline(&mut self, _: &Newline, cx: &mut ViewContext<Self>) {
 802        self.start_transaction(cx);
 803        let mut old_selections = SmallVec::<[_; 32]>::new();
 804        {
 805            let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
 806            let buffer = self.buffer.read(cx);
 807            for selection in selections.iter() {
 808                let start_point = selection.start;
 809                let indent = buffer
 810                    .indent_column_for_line(start_point.row)
 811                    .min(start_point.column);
 812                let start = selection.start.to_offset(buffer);
 813                let end = selection.end.to_offset(buffer);
 814
 815                let mut insert_extra_newline = false;
 816                if let Some(language) = buffer.language() {
 817                    let leading_whitespace_len = buffer
 818                        .reversed_chars_at(start)
 819                        .take_while(|c| c.is_whitespace() && *c != '\n')
 820                        .map(|c| c.len_utf8())
 821                        .sum::<usize>();
 822
 823                    let trailing_whitespace_len = buffer
 824                        .chars_at(end)
 825                        .take_while(|c| c.is_whitespace() && *c != '\n')
 826                        .map(|c| c.len_utf8())
 827                        .sum::<usize>();
 828
 829                    insert_extra_newline = language.brackets().iter().any(|pair| {
 830                        let pair_start = pair.start.trim_end();
 831                        let pair_end = pair.end.trim_start();
 832
 833                        pair.newline
 834                            && buffer.contains_str_at(end + trailing_whitespace_len, pair_end)
 835                            && buffer.contains_str_at(
 836                                (start - leading_whitespace_len).saturating_sub(pair_start.len()),
 837                                pair_start,
 838                            )
 839                    });
 840                }
 841
 842                old_selections.push((selection.id, start..end, indent, insert_extra_newline));
 843            }
 844        }
 845
 846        let mut new_selections = Vec::with_capacity(old_selections.len());
 847        self.buffer.update(cx, |buffer, cx| {
 848            let mut delta = 0_isize;
 849            let mut pending_edit: Option<PendingEdit> = None;
 850            for (_, range, indent, insert_extra_newline) in &old_selections {
 851                if pending_edit.as_ref().map_or(false, |pending| {
 852                    pending.indent != *indent
 853                        || pending.insert_extra_newline != *insert_extra_newline
 854                }) {
 855                    let pending = pending_edit.take().unwrap();
 856                    let mut new_text = String::with_capacity(1 + pending.indent as usize);
 857                    new_text.push('\n');
 858                    new_text.extend(iter::repeat(' ').take(pending.indent as usize));
 859                    if pending.insert_extra_newline {
 860                        new_text = new_text.repeat(2);
 861                    }
 862                    buffer.edit_with_autoindent(pending.ranges, new_text, cx);
 863                    delta += pending.delta;
 864                }
 865
 866                let start = (range.start as isize + delta) as usize;
 867                let end = (range.end as isize + delta) as usize;
 868                let mut text_len = *indent as usize + 1;
 869                if *insert_extra_newline {
 870                    text_len *= 2;
 871                }
 872
 873                let pending = pending_edit.get_or_insert_with(Default::default);
 874                pending.delta += text_len as isize - (end - start) as isize;
 875                pending.indent = *indent;
 876                pending.insert_extra_newline = *insert_extra_newline;
 877                pending.ranges.push(start..end);
 878            }
 879
 880            let pending = pending_edit.unwrap();
 881            let mut new_text = String::with_capacity(1 + pending.indent as usize);
 882            new_text.push('\n');
 883            new_text.extend(iter::repeat(' ').take(pending.indent as usize));
 884            if pending.insert_extra_newline {
 885                new_text = new_text.repeat(2);
 886            }
 887            buffer.edit_with_autoindent(pending.ranges, new_text, cx);
 888
 889            let mut delta = 0_isize;
 890            new_selections.extend(old_selections.into_iter().map(
 891                |(id, range, indent, insert_extra_newline)| {
 892                    let start = (range.start as isize + delta) as usize;
 893                    let end = (range.end as isize + delta) as usize;
 894                    let text_before_cursor_len = indent as usize + 1;
 895                    let cursor = start + text_before_cursor_len;
 896                    let text_len = if insert_extra_newline {
 897                        text_before_cursor_len * 2
 898                    } else {
 899                        text_before_cursor_len
 900                    };
 901                    delta += text_len as isize - (end - start) as isize;
 902                    Selection {
 903                        id,
 904                        start: cursor,
 905                        end: cursor,
 906                        reversed: false,
 907                        goal: SelectionGoal::None,
 908                    }
 909                },
 910            ))
 911        });
 912
 913        self.update_selections(new_selections, true, cx);
 914        self.end_transaction(cx);
 915
 916        #[derive(Default)]
 917        struct PendingEdit {
 918            indent: u32,
 919            insert_extra_newline: bool,
 920            delta: isize,
 921            ranges: SmallVec<[Range<usize>; 32]>,
 922        }
 923    }
 924
 925    fn insert(&mut self, text: &str, cx: &mut ViewContext<Self>) {
 926        self.start_transaction(cx);
 927        let old_selections = self.selections::<usize>(cx).collect::<SmallVec<[_; 32]>>();
 928        let mut new_selections = Vec::new();
 929        self.buffer.update(cx, |buffer, cx| {
 930            let edit_ranges = old_selections.iter().map(|s| s.start..s.end);
 931            buffer.edit_with_autoindent(edit_ranges, text, cx);
 932            let text_len = text.len() as isize;
 933            let mut delta = 0_isize;
 934            new_selections = old_selections
 935                .into_iter()
 936                .map(|selection| {
 937                    let start = selection.start as isize;
 938                    let end = selection.end as isize;
 939                    let cursor = (start + delta + text_len) as usize;
 940                    let deleted_count = end - start;
 941                    delta += text_len - deleted_count;
 942                    Selection {
 943                        id: selection.id,
 944                        start: cursor,
 945                        end: cursor,
 946                        reversed: false,
 947                        goal: SelectionGoal::None,
 948                    }
 949                })
 950                .collect();
 951        });
 952
 953        self.update_selections(new_selections, true, cx);
 954        self.end_transaction(cx);
 955    }
 956
 957    fn autoclose_pairs(&mut self, cx: &mut ViewContext<Self>) {
 958        let selections = self.selections::<usize>(cx).collect::<Vec<_>>();
 959        let new_autoclose_pair_state = self.buffer.update(cx, |buffer, cx| {
 960            let autoclose_pair = buffer.language().and_then(|language| {
 961                let first_selection_start = selections.first().unwrap().start;
 962                let pair = language.brackets().iter().find(|pair| {
 963                    buffer.contains_str_at(
 964                        first_selection_start.saturating_sub(pair.start.len()),
 965                        &pair.start,
 966                    )
 967                });
 968                pair.and_then(|pair| {
 969                    let should_autoclose = selections[1..].iter().all(|selection| {
 970                        buffer.contains_str_at(
 971                            selection.start.saturating_sub(pair.start.len()),
 972                            &pair.start,
 973                        )
 974                    });
 975
 976                    if should_autoclose {
 977                        Some(pair.clone())
 978                    } else {
 979                        None
 980                    }
 981                })
 982            });
 983
 984            autoclose_pair.and_then(|pair| {
 985                let selection_ranges = selections
 986                    .iter()
 987                    .map(|selection| {
 988                        let start = selection.start.to_offset(&*buffer);
 989                        start..start
 990                    })
 991                    .collect::<SmallVec<[_; 32]>>();
 992
 993                buffer.edit(selection_ranges, &pair.end, cx);
 994
 995                if pair.end.len() == 1 {
 996                    let mut delta = 0;
 997                    Some(BracketPairState {
 998                        ranges: buffer.anchor_range_set(selections.iter().map(move |selection| {
 999                            let offset = selection.start + delta;
1000                            delta += 1;
1001                            (offset, Bias::Left)..(offset, Bias::Right)
1002                        })),
1003                        pair,
1004                    })
1005                } else {
1006                    None
1007                }
1008            })
1009        });
1010        self.autoclose_stack.extend(new_autoclose_pair_state);
1011    }
1012
1013    fn skip_autoclose_end(&mut self, text: &str, cx: &mut ViewContext<Self>) -> bool {
1014        let old_selections = self.selections::<usize>(cx).collect::<Vec<_>>();
1015        let autoclose_pair_state = if let Some(autoclose_pair_state) = self.autoclose_stack.last() {
1016            autoclose_pair_state
1017        } else {
1018            return false;
1019        };
1020        if text != autoclose_pair_state.pair.end {
1021            return false;
1022        }
1023
1024        debug_assert_eq!(old_selections.len(), autoclose_pair_state.ranges.len());
1025
1026        let buffer = self.buffer.read(cx);
1027        if old_selections
1028            .iter()
1029            .zip(autoclose_pair_state.ranges.ranges::<usize, _>(buffer))
1030            .all(|(selection, autoclose_range)| {
1031                let autoclose_range_end = autoclose_range.end.to_offset(buffer);
1032                selection.is_empty() && selection.start == autoclose_range_end
1033            })
1034        {
1035            let new_selections = old_selections
1036                .into_iter()
1037                .map(|selection| {
1038                    let cursor = selection.start + 1;
1039                    Selection {
1040                        id: selection.id,
1041                        start: cursor,
1042                        end: cursor,
1043                        reversed: false,
1044                        goal: SelectionGoal::None,
1045                    }
1046                })
1047                .collect();
1048            self.autoclose_stack.pop();
1049            self.update_selections(new_selections, true, cx);
1050            true
1051        } else {
1052            false
1053        }
1054    }
1055
1056    pub fn clear(&mut self, cx: &mut ViewContext<Self>) {
1057        self.start_transaction(cx);
1058        self.select_all(&SelectAll, cx);
1059        self.insert("", cx);
1060        self.end_transaction(cx);
1061    }
1062
1063    pub fn backspace(&mut self, _: &Backspace, cx: &mut ViewContext<Self>) {
1064        self.start_transaction(cx);
1065        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1066        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1067        for selection in &mut selections {
1068            if selection.is_empty() {
1069                let head = selection.head().to_display_point(&display_map);
1070                let cursor = movement::left(&display_map, head)
1071                    .unwrap()
1072                    .to_point(&display_map);
1073                selection.set_head(cursor);
1074                selection.goal = SelectionGoal::None;
1075            }
1076        }
1077        self.update_selections(selections, true, cx);
1078        self.insert("", cx);
1079        self.end_transaction(cx);
1080    }
1081
1082    pub fn delete(&mut self, _: &Delete, cx: &mut ViewContext<Self>) {
1083        self.start_transaction(cx);
1084        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1085        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1086        for selection in &mut selections {
1087            if selection.is_empty() {
1088                let head = selection.head().to_display_point(&display_map);
1089                let cursor = movement::right(&display_map, head)
1090                    .unwrap()
1091                    .to_point(&display_map);
1092                selection.set_head(cursor);
1093                selection.goal = SelectionGoal::None;
1094            }
1095        }
1096        self.update_selections(selections, true, cx);
1097        self.insert(&"", cx);
1098        self.end_transaction(cx);
1099    }
1100
1101    pub fn tab(&mut self, _: &Tab, cx: &mut ViewContext<Self>) {
1102        self.start_transaction(cx);
1103        let tab_size = self.build_settings.borrow()(cx).tab_size;
1104        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1105        self.buffer.update(cx, |buffer, cx| {
1106            let mut last_indented_row = None;
1107            for selection in &mut selections {
1108                if selection.is_empty() {
1109                    let char_column = buffer
1110                        .chars_for_range(Point::new(selection.start.row, 0)..selection.start)
1111                        .count();
1112                    let chars_to_next_tab_stop = tab_size - (char_column % tab_size);
1113                    buffer.edit(
1114                        [selection.start..selection.start],
1115                        " ".repeat(chars_to_next_tab_stop),
1116                        cx,
1117                    );
1118                    selection.start.column += chars_to_next_tab_stop as u32;
1119                    selection.end = selection.start;
1120                } else {
1121                    for row in selection.start.row..=selection.end.row {
1122                        if last_indented_row != Some(row) {
1123                            let char_column = buffer.indent_column_for_line(row) as usize;
1124                            let chars_to_next_tab_stop = tab_size - (char_column % tab_size);
1125                            let row_start = Point::new(row, 0);
1126                            buffer.edit(
1127                                [row_start..row_start],
1128                                " ".repeat(chars_to_next_tab_stop),
1129                                cx,
1130                            );
1131                            last_indented_row = Some(row);
1132                        }
1133                    }
1134                }
1135            }
1136        });
1137
1138        self.update_selections(selections, true, cx);
1139        self.end_transaction(cx);
1140    }
1141
1142    pub fn delete_line(&mut self, _: &DeleteLine, cx: &mut ViewContext<Self>) {
1143        self.start_transaction(cx);
1144
1145        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1146        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1147        let buffer = self.buffer.read(cx);
1148
1149        let mut row_delta = 0;
1150        let mut new_cursors = Vec::new();
1151        let mut edit_ranges = Vec::new();
1152        let mut selections = selections.iter().peekable();
1153        while let Some(selection) = selections.next() {
1154            let mut rows = selection.spanned_rows(false, &display_map).buffer_rows;
1155            let goal_display_column = selection.head().to_display_point(&display_map).column();
1156
1157            // Accumulate contiguous regions of rows that we want to delete.
1158            while let Some(next_selection) = selections.peek() {
1159                let next_rows = next_selection.spanned_rows(false, &display_map).buffer_rows;
1160                if next_rows.start <= rows.end {
1161                    rows.end = next_rows.end;
1162                    selections.next().unwrap();
1163                } else {
1164                    break;
1165                }
1166            }
1167
1168            let mut edit_start = Point::new(rows.start, 0).to_offset(buffer);
1169            let edit_end;
1170            let cursor_buffer_row;
1171            if buffer.max_point().row >= rows.end {
1172                // If there's a line after the range, delete the \n from the end of the row range
1173                // and position the cursor on the next line.
1174                edit_end = Point::new(rows.end, 0).to_offset(buffer);
1175                cursor_buffer_row = rows.start;
1176            } else {
1177                // If there isn't a line after the range, delete the \n from the line before the
1178                // start of the row range and position the cursor there.
1179                edit_start = edit_start.saturating_sub(1);
1180                edit_end = buffer.len();
1181                cursor_buffer_row = rows.start.saturating_sub(1);
1182            }
1183
1184            let mut cursor =
1185                Point::new(cursor_buffer_row - row_delta, 0).to_display_point(&display_map);
1186            *cursor.column_mut() =
1187                cmp::min(goal_display_column, display_map.line_len(cursor.row()));
1188            row_delta += rows.len() as u32;
1189
1190            new_cursors.push((selection.id, cursor.to_point(&display_map)));
1191            edit_ranges.push(edit_start..edit_end);
1192        }
1193
1194        new_cursors.sort_unstable_by_key(|(_, point)| point.clone());
1195        let new_selections = new_cursors
1196            .into_iter()
1197            .map(|(id, cursor)| Selection {
1198                id,
1199                start: cursor,
1200                end: cursor,
1201                reversed: false,
1202                goal: SelectionGoal::None,
1203            })
1204            .collect();
1205        self.buffer
1206            .update(cx, |buffer, cx| buffer.edit(edit_ranges, "", cx));
1207        self.update_selections(new_selections, true, cx);
1208        self.end_transaction(cx);
1209    }
1210
1211    pub fn duplicate_line(&mut self, _: &DuplicateLine, cx: &mut ViewContext<Self>) {
1212        self.start_transaction(cx);
1213
1214        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1215        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1216        let buffer = self.buffer.read(cx);
1217
1218        let mut edits = Vec::new();
1219        let mut selections_iter = selections.iter().peekable();
1220        while let Some(selection) = selections_iter.next() {
1221            // Avoid duplicating the same lines twice.
1222            let mut rows = selection.spanned_rows(false, &display_map).buffer_rows;
1223
1224            while let Some(next_selection) = selections_iter.peek() {
1225                let next_rows = next_selection.spanned_rows(false, &display_map).buffer_rows;
1226                if next_rows.start <= rows.end - 1 {
1227                    rows.end = next_rows.end;
1228                    selections_iter.next().unwrap();
1229                } else {
1230                    break;
1231                }
1232            }
1233
1234            // Copy the text from the selected row region and splice it at the start of the region.
1235            let start = Point::new(rows.start, 0);
1236            let end = Point::new(rows.end - 1, buffer.line_len(rows.end - 1));
1237            let text = buffer
1238                .text_for_range(start..end)
1239                .chain(Some("\n"))
1240                .collect::<String>();
1241            edits.push((start, text, rows.len() as u32));
1242        }
1243
1244        let mut edits_iter = edits.iter().peekable();
1245        let mut row_delta = 0;
1246        for selection in selections.iter_mut() {
1247            while let Some((point, _, line_count)) = edits_iter.peek() {
1248                if *point <= selection.start {
1249                    row_delta += line_count;
1250                    edits_iter.next();
1251                } else {
1252                    break;
1253                }
1254            }
1255            selection.start.row += row_delta;
1256            selection.end.row += row_delta;
1257        }
1258
1259        self.buffer.update(cx, |buffer, cx| {
1260            for (point, text, _) in edits.into_iter().rev() {
1261                buffer.edit(Some(point..point), text, cx);
1262            }
1263        });
1264
1265        self.update_selections(selections, true, cx);
1266        self.end_transaction(cx);
1267    }
1268
1269    pub fn move_line_up(&mut self, _: &MoveLineUp, cx: &mut ViewContext<Self>) {
1270        self.start_transaction(cx);
1271
1272        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1273        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1274        let buffer = self.buffer.read(cx);
1275
1276        let mut edits = Vec::new();
1277        let mut new_selection_ranges = Vec::new();
1278        let mut old_folds = Vec::new();
1279        let mut new_folds = Vec::new();
1280
1281        let mut selections = selections.iter().peekable();
1282        let mut contiguous_selections = Vec::new();
1283        while let Some(selection) = selections.next() {
1284            // Accumulate contiguous regions of rows that we want to move.
1285            contiguous_selections.push(selection.point_range(buffer));
1286            let SpannedRows {
1287                mut buffer_rows,
1288                mut display_rows,
1289            } = selection.spanned_rows(false, &display_map);
1290
1291            while let Some(next_selection) = selections.peek() {
1292                let SpannedRows {
1293                    buffer_rows: next_buffer_rows,
1294                    display_rows: next_display_rows,
1295                } = next_selection.spanned_rows(false, &display_map);
1296                if next_buffer_rows.start <= buffer_rows.end {
1297                    buffer_rows.end = next_buffer_rows.end;
1298                    display_rows.end = next_display_rows.end;
1299                    contiguous_selections.push(next_selection.point_range(buffer));
1300                    selections.next().unwrap();
1301                } else {
1302                    break;
1303                }
1304            }
1305
1306            // Cut the text from the selected rows and paste it at the start of the previous line.
1307            if display_rows.start != 0 {
1308                let start = Point::new(buffer_rows.start, 0).to_offset(buffer);
1309                let end = Point::new(buffer_rows.end - 1, buffer.line_len(buffer_rows.end - 1))
1310                    .to_offset(buffer);
1311
1312                let prev_row_display_start = DisplayPoint::new(display_rows.start - 1, 0);
1313                let prev_row_buffer_start = display_map.prev_row_boundary(prev_row_display_start).1;
1314                let prev_row_buffer_start_offset = prev_row_buffer_start.to_offset(buffer);
1315
1316                let mut text = String::new();
1317                text.extend(buffer.text_for_range(start..end));
1318                text.push('\n');
1319                edits.push((
1320                    prev_row_buffer_start_offset..prev_row_buffer_start_offset,
1321                    text,
1322                ));
1323                edits.push((start - 1..end, String::new()));
1324
1325                let row_delta = buffer_rows.start - prev_row_buffer_start.row;
1326
1327                // Move selections up.
1328                for range in &mut contiguous_selections {
1329                    range.start.row -= row_delta;
1330                    range.end.row -= row_delta;
1331                }
1332
1333                // Move folds up.
1334                old_folds.push(start..end);
1335                for fold in display_map.folds_in_range(start..end) {
1336                    let mut start = fold.start.to_point(buffer);
1337                    let mut end = fold.end.to_point(buffer);
1338                    start.row -= row_delta;
1339                    end.row -= row_delta;
1340                    new_folds.push(start..end);
1341                }
1342            }
1343
1344            new_selection_ranges.extend(contiguous_selections.drain(..));
1345        }
1346
1347        self.unfold_ranges(old_folds, cx);
1348        self.buffer.update(cx, |buffer, cx| {
1349            for (range, text) in edits.into_iter().rev() {
1350                buffer.edit(Some(range), text, cx);
1351            }
1352        });
1353        self.fold_ranges(new_folds, cx);
1354        self.select_ranges(new_selection_ranges, true, cx);
1355
1356        self.end_transaction(cx);
1357    }
1358
1359    pub fn move_line_down(&mut self, _: &MoveLineDown, cx: &mut ViewContext<Self>) {
1360        self.start_transaction(cx);
1361
1362        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1363        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1364        let buffer = self.buffer.read(cx);
1365
1366        let mut edits = Vec::new();
1367        let mut new_selection_ranges = Vec::new();
1368        let mut old_folds = Vec::new();
1369        let mut new_folds = Vec::new();
1370
1371        let mut selections = selections.iter().peekable();
1372        let mut contiguous_selections = Vec::new();
1373        while let Some(selection) = selections.next() {
1374            // Accumulate contiguous regions of rows that we want to move.
1375            contiguous_selections.push(selection.point_range(buffer));
1376            let SpannedRows {
1377                mut buffer_rows,
1378                mut display_rows,
1379            } = selection.spanned_rows(false, &display_map);
1380            while let Some(next_selection) = selections.peek() {
1381                let SpannedRows {
1382                    buffer_rows: next_buffer_rows,
1383                    display_rows: next_display_rows,
1384                } = next_selection.spanned_rows(false, &display_map);
1385                if next_buffer_rows.start <= buffer_rows.end {
1386                    buffer_rows.end = next_buffer_rows.end;
1387                    display_rows.end = next_display_rows.end;
1388                    contiguous_selections.push(next_selection.point_range(buffer));
1389                    selections.next().unwrap();
1390                } else {
1391                    break;
1392                }
1393            }
1394
1395            // Cut the text from the selected rows and paste it at the end of the next line.
1396            if display_rows.end <= display_map.max_point().row() {
1397                let start = Point::new(buffer_rows.start, 0).to_offset(buffer);
1398                let end = Point::new(buffer_rows.end - 1, buffer.line_len(buffer_rows.end - 1))
1399                    .to_offset(buffer);
1400
1401                let next_row_display_end =
1402                    DisplayPoint::new(display_rows.end, display_map.line_len(display_rows.end));
1403                let next_row_buffer_end = display_map.next_row_boundary(next_row_display_end).1;
1404                let next_row_buffer_end_offset = next_row_buffer_end.to_offset(buffer);
1405
1406                let mut text = String::new();
1407                text.push('\n');
1408                text.extend(buffer.text_for_range(start..end));
1409                edits.push((start..end + 1, String::new()));
1410                edits.push((next_row_buffer_end_offset..next_row_buffer_end_offset, text));
1411
1412                let row_delta = next_row_buffer_end.row - buffer_rows.end + 1;
1413
1414                // Move selections down.
1415                for range in &mut contiguous_selections {
1416                    range.start.row += row_delta;
1417                    range.end.row += row_delta;
1418                }
1419
1420                // Move folds down.
1421                old_folds.push(start..end);
1422                for fold in display_map.folds_in_range(start..end) {
1423                    let mut start = fold.start.to_point(buffer);
1424                    let mut end = fold.end.to_point(buffer);
1425                    start.row += row_delta;
1426                    end.row += row_delta;
1427                    new_folds.push(start..end);
1428                }
1429            }
1430
1431            new_selection_ranges.extend(contiguous_selections.drain(..));
1432        }
1433
1434        self.unfold_ranges(old_folds, cx);
1435        self.buffer.update(cx, |buffer, cx| {
1436            for (range, text) in edits.into_iter().rev() {
1437                buffer.edit(Some(range), text, cx);
1438            }
1439        });
1440        self.fold_ranges(new_folds, cx);
1441        self.select_ranges(new_selection_ranges, true, cx);
1442
1443        self.end_transaction(cx);
1444    }
1445
1446    pub fn cut(&mut self, _: &Cut, cx: &mut ViewContext<Self>) {
1447        self.start_transaction(cx);
1448        let mut text = String::new();
1449        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1450        let mut clipboard_selections = Vec::with_capacity(selections.len());
1451        {
1452            let buffer = self.buffer.read(cx);
1453            let max_point = buffer.max_point();
1454            for selection in &mut selections {
1455                let is_entire_line = selection.is_empty();
1456                if is_entire_line {
1457                    selection.start = Point::new(selection.start.row, 0);
1458                    selection.end = cmp::min(max_point, Point::new(selection.end.row + 1, 0));
1459                }
1460                let mut len = 0;
1461                for chunk in buffer.text_for_range(selection.start..selection.end) {
1462                    text.push_str(chunk);
1463                    len += chunk.len();
1464                }
1465                clipboard_selections.push(ClipboardSelection {
1466                    len,
1467                    is_entire_line,
1468                });
1469            }
1470        }
1471        self.update_selections(selections, true, cx);
1472        self.insert("", cx);
1473        self.end_transaction(cx);
1474
1475        cx.as_mut()
1476            .write_to_clipboard(ClipboardItem::new(text).with_metadata(clipboard_selections));
1477    }
1478
1479    pub fn copy(&mut self, _: &Copy, cx: &mut ViewContext<Self>) {
1480        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1481        let buffer = self.buffer.read(cx);
1482        let max_point = buffer.max_point();
1483        let mut text = String::new();
1484        let mut clipboard_selections = Vec::with_capacity(selections.len());
1485        for selection in selections.iter() {
1486            let mut start = selection.start;
1487            let mut end = selection.end;
1488            let is_entire_line = selection.is_empty();
1489            if is_entire_line {
1490                start = Point::new(start.row, 0);
1491                end = cmp::min(max_point, Point::new(start.row + 1, 0));
1492            }
1493            let mut len = 0;
1494            for chunk in buffer.text_for_range(start..end) {
1495                text.push_str(chunk);
1496                len += chunk.len();
1497            }
1498            clipboard_selections.push(ClipboardSelection {
1499                len,
1500                is_entire_line,
1501            });
1502        }
1503
1504        cx.as_mut()
1505            .write_to_clipboard(ClipboardItem::new(text).with_metadata(clipboard_selections));
1506    }
1507
1508    pub fn paste(&mut self, _: &Paste, cx: &mut ViewContext<Self>) {
1509        if let Some(item) = cx.as_mut().read_from_clipboard() {
1510            let clipboard_text = item.text();
1511            if let Some(mut clipboard_selections) = item.metadata::<Vec<ClipboardSelection>>() {
1512                let mut selections = self.selections::<usize>(cx).collect::<Vec<_>>();
1513                let all_selections_were_entire_line =
1514                    clipboard_selections.iter().all(|s| s.is_entire_line);
1515                if clipboard_selections.len() != selections.len() {
1516                    clipboard_selections.clear();
1517                }
1518
1519                let mut delta = 0_isize;
1520                let mut start_offset = 0;
1521                for (i, selection) in selections.iter_mut().enumerate() {
1522                    let to_insert;
1523                    let entire_line;
1524                    if let Some(clipboard_selection) = clipboard_selections.get(i) {
1525                        let end_offset = start_offset + clipboard_selection.len;
1526                        to_insert = &clipboard_text[start_offset..end_offset];
1527                        entire_line = clipboard_selection.is_entire_line;
1528                        start_offset = end_offset
1529                    } else {
1530                        to_insert = clipboard_text.as_str();
1531                        entire_line = all_selections_were_entire_line;
1532                    }
1533
1534                    selection.start = (selection.start as isize + delta) as usize;
1535                    selection.end = (selection.end as isize + delta) as usize;
1536
1537                    self.buffer.update(cx, |buffer, cx| {
1538                        // If the corresponding selection was empty when this slice of the
1539                        // clipboard text was written, then the entire line containing the
1540                        // selection was copied. If this selection is also currently empty,
1541                        // then paste the line before the current line of the buffer.
1542                        let range = if selection.is_empty() && entire_line {
1543                            let column = selection.start.to_point(&*buffer).column as usize;
1544                            let line_start = selection.start - column;
1545                            line_start..line_start
1546                        } else {
1547                            selection.start..selection.end
1548                        };
1549
1550                        delta += to_insert.len() as isize - range.len() as isize;
1551                        buffer.edit([range], to_insert, cx);
1552                        selection.start += to_insert.len();
1553                        selection.end = selection.start;
1554                    });
1555                }
1556                self.update_selections(selections, true, cx);
1557            } else {
1558                self.insert(clipboard_text, cx);
1559            }
1560        }
1561    }
1562
1563    pub fn undo(&mut self, _: &Undo, cx: &mut ViewContext<Self>) {
1564        self.buffer.update(cx, |buffer, cx| buffer.undo(cx));
1565        self.request_autoscroll(cx);
1566    }
1567
1568    pub fn redo(&mut self, _: &Redo, cx: &mut ViewContext<Self>) {
1569        self.buffer.update(cx, |buffer, cx| buffer.redo(cx));
1570        self.request_autoscroll(cx);
1571    }
1572
1573    pub fn move_left(&mut self, _: &MoveLeft, cx: &mut ViewContext<Self>) {
1574        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1575        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1576        for selection in &mut selections {
1577            let start = selection.start.to_display_point(&display_map);
1578            let end = selection.end.to_display_point(&display_map);
1579
1580            if start != end {
1581                selection.end = selection.start.clone();
1582            } else {
1583                let cursor = movement::left(&display_map, start)
1584                    .unwrap()
1585                    .to_point(&display_map);
1586                selection.start = cursor.clone();
1587                selection.end = cursor;
1588            }
1589            selection.reversed = false;
1590            selection.goal = SelectionGoal::None;
1591        }
1592        self.update_selections(selections, true, cx);
1593    }
1594
1595    pub fn select_left(&mut self, _: &SelectLeft, cx: &mut ViewContext<Self>) {
1596        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1597        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1598        for selection in &mut selections {
1599            let head = selection.head().to_display_point(&display_map);
1600            let cursor = movement::left(&display_map, head)
1601                .unwrap()
1602                .to_point(&display_map);
1603            selection.set_head(cursor);
1604            selection.goal = SelectionGoal::None;
1605        }
1606        self.update_selections(selections, true, cx);
1607    }
1608
1609    pub fn move_right(&mut self, _: &MoveRight, cx: &mut ViewContext<Self>) {
1610        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1611        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1612        for selection in &mut selections {
1613            let start = selection.start.to_display_point(&display_map);
1614            let end = selection.end.to_display_point(&display_map);
1615
1616            if start != end {
1617                selection.start = selection.end.clone();
1618            } else {
1619                let cursor = movement::right(&display_map, end)
1620                    .unwrap()
1621                    .to_point(&display_map);
1622                selection.start = cursor;
1623                selection.end = cursor;
1624            }
1625            selection.reversed = false;
1626            selection.goal = SelectionGoal::None;
1627        }
1628        self.update_selections(selections, true, cx);
1629    }
1630
1631    pub fn select_right(&mut self, _: &SelectRight, cx: &mut ViewContext<Self>) {
1632        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1633        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1634        for selection in &mut selections {
1635            let head = selection.head().to_display_point(&display_map);
1636            let cursor = movement::right(&display_map, head)
1637                .unwrap()
1638                .to_point(&display_map);
1639            selection.set_head(cursor);
1640            selection.goal = SelectionGoal::None;
1641        }
1642        self.update_selections(selections, true, cx);
1643    }
1644
1645    pub fn move_up(&mut self, _: &MoveUp, cx: &mut ViewContext<Self>) {
1646        if matches!(self.mode, EditorMode::SingleLine) {
1647            cx.propagate_action();
1648            return;
1649        }
1650
1651        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1652        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1653        for selection in &mut selections {
1654            let start = selection.start.to_display_point(&display_map);
1655            let end = selection.end.to_display_point(&display_map);
1656            if start != end {
1657                selection.goal = SelectionGoal::None;
1658            }
1659
1660            let (start, goal) = movement::up(&display_map, start, selection.goal).unwrap();
1661            let cursor = start.to_point(&display_map);
1662            selection.start = cursor;
1663            selection.end = cursor;
1664            selection.goal = goal;
1665            selection.reversed = false;
1666        }
1667        self.update_selections(selections, true, cx);
1668    }
1669
1670    pub fn select_up(&mut self, _: &SelectUp, cx: &mut ViewContext<Self>) {
1671        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1672        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1673        for selection in &mut selections {
1674            let head = selection.head().to_display_point(&display_map);
1675            let (head, goal) = movement::up(&display_map, head, selection.goal).unwrap();
1676            let cursor = head.to_point(&display_map);
1677            selection.set_head(cursor);
1678            selection.goal = goal;
1679        }
1680        self.update_selections(selections, true, cx);
1681    }
1682
1683    pub fn move_down(&mut self, _: &MoveDown, cx: &mut ViewContext<Self>) {
1684        if matches!(self.mode, EditorMode::SingleLine) {
1685            cx.propagate_action();
1686            return;
1687        }
1688
1689        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1690        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1691        for selection in &mut selections {
1692            let start = selection.start.to_display_point(&display_map);
1693            let end = selection.end.to_display_point(&display_map);
1694            if start != end {
1695                selection.goal = SelectionGoal::None;
1696            }
1697
1698            let (start, goal) = movement::down(&display_map, end, selection.goal).unwrap();
1699            let cursor = start.to_point(&display_map);
1700            selection.start = cursor;
1701            selection.end = cursor;
1702            selection.goal = goal;
1703            selection.reversed = false;
1704        }
1705        self.update_selections(selections, true, cx);
1706    }
1707
1708    pub fn select_down(&mut self, _: &SelectDown, cx: &mut ViewContext<Self>) {
1709        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1710        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1711        for selection in &mut selections {
1712            let head = selection.head().to_display_point(&display_map);
1713            let (head, goal) = movement::down(&display_map, head, selection.goal).unwrap();
1714            let cursor = head.to_point(&display_map);
1715            selection.set_head(cursor);
1716            selection.goal = goal;
1717        }
1718        self.update_selections(selections, true, cx);
1719    }
1720
1721    pub fn move_to_previous_word_boundary(
1722        &mut self,
1723        _: &MoveToPreviousWordBoundary,
1724        cx: &mut ViewContext<Self>,
1725    ) {
1726        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1727        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1728        for selection in &mut selections {
1729            let head = selection.head().to_display_point(&display_map);
1730            let new_head = movement::prev_word_boundary(&display_map, head).unwrap();
1731            let cursor = new_head.to_point(&display_map);
1732            selection.start = cursor.clone();
1733            selection.end = cursor;
1734            selection.reversed = false;
1735            selection.goal = SelectionGoal::None;
1736        }
1737        self.update_selections(selections, true, cx);
1738    }
1739
1740    pub fn select_to_previous_word_boundary(
1741        &mut self,
1742        _: &SelectToPreviousWordBoundary,
1743        cx: &mut ViewContext<Self>,
1744    ) {
1745        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1746        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1747        for selection in &mut selections {
1748            let head = selection.head().to_display_point(&display_map);
1749            let new_head = movement::prev_word_boundary(&display_map, head).unwrap();
1750            let cursor = new_head.to_point(&display_map);
1751            selection.set_head(cursor);
1752            selection.goal = SelectionGoal::None;
1753        }
1754        self.update_selections(selections, true, cx);
1755    }
1756
1757    pub fn delete_to_previous_word_boundary(
1758        &mut self,
1759        _: &DeleteToPreviousWordBoundary,
1760        cx: &mut ViewContext<Self>,
1761    ) {
1762        self.start_transaction(cx);
1763        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1764        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1765        for selection in &mut selections {
1766            if selection.is_empty() {
1767                let head = selection.head().to_display_point(&display_map);
1768                let new_head = movement::prev_word_boundary(&display_map, head).unwrap();
1769                let cursor = new_head.to_point(&display_map);
1770                selection.set_head(cursor);
1771                selection.goal = SelectionGoal::None;
1772            }
1773        }
1774        self.update_selections(selections, true, cx);
1775        self.insert("", cx);
1776        self.end_transaction(cx);
1777    }
1778
1779    pub fn move_to_next_word_boundary(
1780        &mut self,
1781        _: &MoveToNextWordBoundary,
1782        cx: &mut ViewContext<Self>,
1783    ) {
1784        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1785        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1786        for selection in &mut selections {
1787            let head = selection.head().to_display_point(&display_map);
1788            let new_head = movement::next_word_boundary(&display_map, head).unwrap();
1789            let cursor = new_head.to_point(&display_map);
1790            selection.start = cursor;
1791            selection.end = cursor;
1792            selection.reversed = false;
1793            selection.goal = SelectionGoal::None;
1794        }
1795        self.update_selections(selections, true, cx);
1796    }
1797
1798    pub fn select_to_next_word_boundary(
1799        &mut self,
1800        _: &SelectToNextWordBoundary,
1801        cx: &mut ViewContext<Self>,
1802    ) {
1803        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1804        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1805        for selection in &mut selections {
1806            let head = selection.head().to_display_point(&display_map);
1807            let new_head = movement::next_word_boundary(&display_map, head).unwrap();
1808            let cursor = new_head.to_point(&display_map);
1809            selection.set_head(cursor);
1810            selection.goal = SelectionGoal::None;
1811        }
1812        self.update_selections(selections, true, cx);
1813    }
1814
1815    pub fn delete_to_next_word_boundary(
1816        &mut self,
1817        _: &DeleteToNextWordBoundary,
1818        cx: &mut ViewContext<Self>,
1819    ) {
1820        self.start_transaction(cx);
1821        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1822        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1823        for selection in &mut selections {
1824            if selection.is_empty() {
1825                let head = selection.head().to_display_point(&display_map);
1826                let new_head = movement::next_word_boundary(&display_map, head).unwrap();
1827                let cursor = new_head.to_point(&display_map);
1828                selection.set_head(cursor);
1829                selection.goal = SelectionGoal::None;
1830            }
1831        }
1832        self.update_selections(selections, true, cx);
1833        self.insert("", cx);
1834        self.end_transaction(cx);
1835    }
1836
1837    pub fn move_to_beginning_of_line(
1838        &mut self,
1839        _: &MoveToBeginningOfLine,
1840        cx: &mut ViewContext<Self>,
1841    ) {
1842        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1843        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1844        for selection in &mut selections {
1845            let head = selection.head().to_display_point(&display_map);
1846            let new_head = movement::line_beginning(&display_map, head, true).unwrap();
1847            let cursor = new_head.to_point(&display_map);
1848            selection.start = cursor;
1849            selection.end = cursor;
1850            selection.reversed = false;
1851            selection.goal = SelectionGoal::None;
1852        }
1853        self.update_selections(selections, true, cx);
1854    }
1855
1856    pub fn select_to_beginning_of_line(
1857        &mut self,
1858        SelectToBeginningOfLine(toggle_indent): &SelectToBeginningOfLine,
1859        cx: &mut ViewContext<Self>,
1860    ) {
1861        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1862        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1863        for selection in &mut selections {
1864            let head = selection.head().to_display_point(&display_map);
1865            let new_head = movement::line_beginning(&display_map, head, *toggle_indent).unwrap();
1866            selection.set_head(new_head.to_point(&display_map));
1867            selection.goal = SelectionGoal::None;
1868        }
1869        self.update_selections(selections, true, cx);
1870    }
1871
1872    pub fn delete_to_beginning_of_line(
1873        &mut self,
1874        _: &DeleteToBeginningOfLine,
1875        cx: &mut ViewContext<Self>,
1876    ) {
1877        self.start_transaction(cx);
1878        self.select_to_beginning_of_line(&SelectToBeginningOfLine(false), cx);
1879        self.backspace(&Backspace, cx);
1880        self.end_transaction(cx);
1881    }
1882
1883    pub fn move_to_end_of_line(&mut self, _: &MoveToEndOfLine, cx: &mut ViewContext<Self>) {
1884        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1885        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1886        {
1887            for selection in &mut selections {
1888                let head = selection.head().to_display_point(&display_map);
1889                let new_head = movement::line_end(&display_map, head).unwrap();
1890                let anchor = new_head.to_point(&display_map);
1891                selection.start = anchor.clone();
1892                selection.end = anchor;
1893                selection.reversed = false;
1894                selection.goal = SelectionGoal::None;
1895            }
1896        }
1897        self.update_selections(selections, true, cx);
1898    }
1899
1900    pub fn select_to_end_of_line(&mut self, _: &SelectToEndOfLine, cx: &mut ViewContext<Self>) {
1901        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1902        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1903        for selection in &mut selections {
1904            let head = selection.head().to_display_point(&display_map);
1905            let new_head = movement::line_end(&display_map, head).unwrap();
1906            selection.set_head(new_head.to_point(&display_map));
1907            selection.goal = SelectionGoal::None;
1908        }
1909        self.update_selections(selections, true, cx);
1910    }
1911
1912    pub fn delete_to_end_of_line(&mut self, _: &DeleteToEndOfLine, cx: &mut ViewContext<Self>) {
1913        self.start_transaction(cx);
1914        self.select_to_end_of_line(&SelectToEndOfLine, cx);
1915        self.delete(&Delete, cx);
1916        self.end_transaction(cx);
1917    }
1918
1919    pub fn cut_to_end_of_line(&mut self, _: &CutToEndOfLine, cx: &mut ViewContext<Self>) {
1920        self.start_transaction(cx);
1921        self.select_to_end_of_line(&SelectToEndOfLine, cx);
1922        self.cut(&Cut, cx);
1923        self.end_transaction(cx);
1924    }
1925
1926    pub fn move_to_beginning(&mut self, _: &MoveToBeginning, cx: &mut ViewContext<Self>) {
1927        let selection = Selection {
1928            id: post_inc(&mut self.next_selection_id),
1929            start: 0,
1930            end: 0,
1931            reversed: false,
1932            goal: SelectionGoal::None,
1933        };
1934        self.update_selections(vec![selection], true, cx);
1935    }
1936
1937    pub fn select_to_beginning(&mut self, _: &SelectToBeginning, cx: &mut ViewContext<Self>) {
1938        let mut selection = self.selections::<Point>(cx).last().unwrap().clone();
1939        selection.set_head(Point::zero());
1940        self.update_selections(vec![selection], true, cx);
1941    }
1942
1943    pub fn move_to_end(&mut self, _: &MoveToEnd, cx: &mut ViewContext<Self>) {
1944        let buffer = self.buffer.read(cx);
1945        let cursor = buffer.len();
1946        let selection = Selection {
1947            id: post_inc(&mut self.next_selection_id),
1948            start: cursor,
1949            end: cursor,
1950            reversed: false,
1951            goal: SelectionGoal::None,
1952        };
1953        self.update_selections(vec![selection], true, cx);
1954    }
1955
1956    pub fn select_to_end(&mut self, _: &SelectToEnd, cx: &mut ViewContext<Self>) {
1957        let mut selection = self.selections::<usize>(cx).last().unwrap().clone();
1958        selection.set_head(self.buffer.read(cx).len());
1959        self.update_selections(vec![selection], true, cx);
1960    }
1961
1962    pub fn select_all(&mut self, _: &SelectAll, cx: &mut ViewContext<Self>) {
1963        let selection = Selection {
1964            id: post_inc(&mut self.next_selection_id),
1965            start: 0,
1966            end: self.buffer.read(cx).len(),
1967            reversed: false,
1968            goal: SelectionGoal::None,
1969        };
1970        self.update_selections(vec![selection], false, cx);
1971    }
1972
1973    pub fn select_line(&mut self, _: &SelectLine, cx: &mut ViewContext<Self>) {
1974        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1975        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1976        let buffer = self.buffer.read(cx);
1977        let max_point = buffer.max_point();
1978        for selection in &mut selections {
1979            let rows = selection.spanned_rows(true, &display_map).buffer_rows;
1980            selection.start = Point::new(rows.start, 0);
1981            selection.end = cmp::min(max_point, Point::new(rows.end, 0));
1982            selection.reversed = false;
1983        }
1984        self.update_selections(selections, true, cx);
1985    }
1986
1987    pub fn split_selection_into_lines(
1988        &mut self,
1989        _: &SplitSelectionIntoLines,
1990        cx: &mut ViewContext<Self>,
1991    ) {
1992        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
1993        let buffer = self.buffer.read(cx);
1994
1995        let mut to_unfold = Vec::new();
1996        let mut new_selections = Vec::new();
1997        for selection in selections.iter() {
1998            if selection.start.row != selection.end.row {
1999                new_selections.push(Selection {
2000                    id: post_inc(&mut self.next_selection_id),
2001                    start: selection.start,
2002                    end: selection.start,
2003                    reversed: false,
2004                    goal: SelectionGoal::None,
2005                });
2006            }
2007            for row in selection.start.row + 1..selection.end.row {
2008                let cursor = Point::new(row, buffer.line_len(row));
2009                new_selections.push(Selection {
2010                    id: post_inc(&mut self.next_selection_id),
2011                    start: cursor,
2012                    end: cursor,
2013                    reversed: false,
2014                    goal: SelectionGoal::None,
2015                });
2016            }
2017            new_selections.push(Selection {
2018                id: selection.id,
2019                start: selection.end,
2020                end: selection.end,
2021                reversed: false,
2022                goal: SelectionGoal::None,
2023            });
2024            to_unfold.push(selection.start..selection.end);
2025        }
2026        self.unfold_ranges(to_unfold, cx);
2027        self.update_selections(new_selections, true, cx);
2028    }
2029
2030    pub fn add_selection_above(&mut self, _: &AddSelectionAbove, cx: &mut ViewContext<Self>) {
2031        self.add_selection(true, cx);
2032    }
2033
2034    pub fn add_selection_below(&mut self, _: &AddSelectionBelow, cx: &mut ViewContext<Self>) {
2035        self.add_selection(false, cx);
2036    }
2037
2038    fn add_selection(&mut self, above: bool, cx: &mut ViewContext<Self>) {
2039        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2040        let mut selections = self.selections::<Point>(cx).collect::<Vec<_>>();
2041        let mut state = self.add_selections_state.take().unwrap_or_else(|| {
2042            let oldest_selection = selections.iter().min_by_key(|s| s.id).unwrap().clone();
2043            let range = oldest_selection.display_range(&display_map).sorted();
2044            let columns = cmp::min(range.start.column(), range.end.column())
2045                ..cmp::max(range.start.column(), range.end.column());
2046
2047            selections.clear();
2048            let mut stack = Vec::new();
2049            for row in range.start.row()..=range.end.row() {
2050                if let Some(selection) = self.build_columnar_selection(
2051                    &display_map,
2052                    row,
2053                    &columns,
2054                    oldest_selection.reversed,
2055                ) {
2056                    stack.push(selection.id);
2057                    selections.push(selection);
2058                }
2059            }
2060
2061            if above {
2062                stack.reverse();
2063            }
2064
2065            AddSelectionsState { above, stack }
2066        });
2067
2068        let last_added_selection = *state.stack.last().unwrap();
2069        let mut new_selections = Vec::new();
2070        if above == state.above {
2071            let end_row = if above {
2072                0
2073            } else {
2074                display_map.max_point().row()
2075            };
2076
2077            'outer: for selection in selections {
2078                if selection.id == last_added_selection {
2079                    let range = selection.display_range(&display_map).sorted();
2080                    debug_assert_eq!(range.start.row(), range.end.row());
2081                    let mut row = range.start.row();
2082                    let columns = if let SelectionGoal::ColumnRange { start, end } = selection.goal
2083                    {
2084                        start..end
2085                    } else {
2086                        cmp::min(range.start.column(), range.end.column())
2087                            ..cmp::max(range.start.column(), range.end.column())
2088                    };
2089
2090                    while row != end_row {
2091                        if above {
2092                            row -= 1;
2093                        } else {
2094                            row += 1;
2095                        }
2096
2097                        if let Some(new_selection) = self.build_columnar_selection(
2098                            &display_map,
2099                            row,
2100                            &columns,
2101                            selection.reversed,
2102                        ) {
2103                            state.stack.push(new_selection.id);
2104                            if above {
2105                                new_selections.push(new_selection);
2106                                new_selections.push(selection);
2107                            } else {
2108                                new_selections.push(selection);
2109                                new_selections.push(new_selection);
2110                            }
2111
2112                            continue 'outer;
2113                        }
2114                    }
2115                }
2116
2117                new_selections.push(selection);
2118            }
2119        } else {
2120            new_selections = selections;
2121            new_selections.retain(|s| s.id != last_added_selection);
2122            state.stack.pop();
2123        }
2124
2125        self.update_selections(new_selections, true, cx);
2126        if state.stack.len() > 1 {
2127            self.add_selections_state = Some(state);
2128        }
2129    }
2130
2131    pub fn select_larger_syntax_node(
2132        &mut self,
2133        _: &SelectLargerSyntaxNode,
2134        cx: &mut ViewContext<Self>,
2135    ) {
2136        let old_selections = self.selections::<usize>(cx).collect::<Box<_>>();
2137        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2138        let buffer = self.buffer.read(cx);
2139
2140        let mut stack = mem::take(&mut self.select_larger_syntax_node_stack);
2141        let mut selected_larger_node = false;
2142        let mut new_selections = old_selections
2143            .iter()
2144            .map(|selection| {
2145                let old_range = selection.start..selection.end;
2146                let mut new_range = old_range.clone();
2147                while let Some(containing_range) =
2148                    buffer.range_for_syntax_ancestor(new_range.clone())
2149                {
2150                    new_range = containing_range;
2151                    if !display_map.intersects_fold(new_range.start)
2152                        && !display_map.intersects_fold(new_range.end)
2153                    {
2154                        break;
2155                    }
2156                }
2157
2158                selected_larger_node |= new_range != old_range;
2159                Selection {
2160                    id: selection.id,
2161                    start: new_range.start,
2162                    end: new_range.end,
2163                    goal: SelectionGoal::None,
2164                    reversed: selection.reversed,
2165                }
2166            })
2167            .collect::<Vec<_>>();
2168
2169        if selected_larger_node {
2170            stack.push(old_selections);
2171            new_selections.sort_unstable_by_key(|selection| selection.start);
2172            self.update_selections(new_selections, true, cx);
2173        }
2174        self.select_larger_syntax_node_stack = stack;
2175    }
2176
2177    pub fn select_smaller_syntax_node(
2178        &mut self,
2179        _: &SelectSmallerSyntaxNode,
2180        cx: &mut ViewContext<Self>,
2181    ) {
2182        let mut stack = mem::take(&mut self.select_larger_syntax_node_stack);
2183        if let Some(selections) = stack.pop() {
2184            self.update_selections(selections.to_vec(), true, cx);
2185        }
2186        self.select_larger_syntax_node_stack = stack;
2187    }
2188
2189    pub fn move_to_enclosing_bracket(
2190        &mut self,
2191        _: &MoveToEnclosingBracket,
2192        cx: &mut ViewContext<Self>,
2193    ) {
2194        let mut selections = self.selections::<usize>(cx).collect::<Vec<_>>();
2195        let buffer = self.buffer.read(cx.as_ref());
2196        for selection in &mut selections {
2197            if let Some((open_range, close_range)) =
2198                buffer.enclosing_bracket_ranges(selection.start..selection.end)
2199            {
2200                let close_range = close_range.to_inclusive();
2201                let destination = if close_range.contains(&selection.start)
2202                    && close_range.contains(&selection.end)
2203                {
2204                    open_range.end
2205                } else {
2206                    *close_range.start()
2207                };
2208                selection.start = destination;
2209                selection.end = destination;
2210            }
2211        }
2212
2213        self.update_selections(selections, true, cx);
2214    }
2215
2216    pub fn show_next_diagnostic(&mut self, _: &ShowNextDiagnostic, cx: &mut ViewContext<Self>) {
2217        let selection = self.newest_selection::<usize>(cx);
2218        let buffer = self.buffer.read(cx.as_ref());
2219        let active_primary_range = self.active_diagnostics.as_ref().map(|active_diagnostics| {
2220            active_diagnostics
2221                .primary_range
2222                .to_offset(buffer)
2223                .to_inclusive()
2224        });
2225        let mut search_start = if let Some(active_primary_range) = active_primary_range.as_ref() {
2226            if active_primary_range.contains(&selection.head()) {
2227                *active_primary_range.end()
2228            } else {
2229                selection.head()
2230            }
2231        } else {
2232            selection.head()
2233        };
2234
2235        loop {
2236            let next_group = buffer
2237                .diagnostics_in_range::<_, usize>(search_start..buffer.len())
2238                .filter(|(_, diagnostic)| diagnostic.is_primary)
2239                .skip_while(|(range, _)| {
2240                    Some(range.end) == active_primary_range.as_ref().map(|r| *r.end())
2241                })
2242                .next()
2243                .map(|(range, diagnostic)| (range, diagnostic.group_id));
2244
2245            if let Some((primary_range, group_id)) = next_group {
2246                self.dismiss_diagnostics(cx);
2247                self.active_diagnostics = self.display_map.update(cx, |display_map, cx| {
2248                    let buffer = self.buffer.read(cx);
2249                    let diagnostic_group = buffer
2250                        .diagnostic_group::<Point>(group_id)
2251                        .map(|(range, diagnostic)| (range, diagnostic.message.clone()))
2252                        .collect::<Vec<_>>();
2253                    let primary_range = buffer.anchor_after(primary_range.start)
2254                        ..buffer.anchor_before(primary_range.end);
2255
2256                    let block_ids = display_map
2257                        .insert_blocks(
2258                            diagnostic_group
2259                                .iter()
2260                                .map(|(range, message)| BlockProperties {
2261                                    position: range.start,
2262                                    text: message.as_str(),
2263                                    runs: vec![],
2264                                    disposition: BlockDisposition::Above,
2265                                }),
2266                            cx,
2267                        )
2268                        .into_iter()
2269                        .collect();
2270
2271                    Some(ActiveDiagnosticGroup {
2272                        primary_range,
2273                        block_ids,
2274                    })
2275                });
2276
2277                self.update_selections(
2278                    vec![Selection {
2279                        id: selection.id,
2280                        start: primary_range.start,
2281                        end: primary_range.start,
2282                        reversed: false,
2283                        goal: SelectionGoal::None,
2284                    }],
2285                    true,
2286                    cx,
2287                );
2288                break;
2289            } else if search_start == 0 {
2290                break;
2291            } else {
2292                // Cycle around to the start of the buffer.
2293                search_start = 0;
2294            }
2295        }
2296    }
2297
2298    fn dismiss_diagnostics(&mut self, cx: &mut ViewContext<Self>) {
2299        if let Some(active_diagnostic_group) = self.active_diagnostics.take() {
2300            self.display_map.update(cx, |display_map, cx| {
2301                display_map.remove_blocks(active_diagnostic_group.block_ids, cx);
2302            });
2303            cx.notify();
2304        }
2305    }
2306
2307    fn build_columnar_selection(
2308        &mut self,
2309        display_map: &DisplayMapSnapshot,
2310        row: u32,
2311        columns: &Range<u32>,
2312        reversed: bool,
2313    ) -> Option<Selection<Point>> {
2314        let is_empty = columns.start == columns.end;
2315        let line_len = display_map.line_len(row);
2316        if columns.start < line_len || (is_empty && columns.start == line_len) {
2317            let start = DisplayPoint::new(row, columns.start);
2318            let end = DisplayPoint::new(row, cmp::min(columns.end, line_len));
2319            Some(Selection {
2320                id: post_inc(&mut self.next_selection_id),
2321                start: start.to_point(display_map),
2322                end: end.to_point(display_map),
2323                reversed,
2324                goal: SelectionGoal::ColumnRange {
2325                    start: columns.start,
2326                    end: columns.end,
2327                },
2328            })
2329        } else {
2330            None
2331        }
2332    }
2333
2334    pub fn active_selection_sets<'a>(
2335        &'a self,
2336        cx: &'a AppContext,
2337    ) -> impl 'a + Iterator<Item = SelectionSetId> {
2338        let buffer = self.buffer.read(cx);
2339        let replica_id = buffer.replica_id();
2340        buffer
2341            .selection_sets()
2342            .filter(move |(set_id, set)| {
2343                set.active && (set_id.replica_id != replica_id || **set_id == self.selection_set_id)
2344            })
2345            .map(|(set_id, _)| *set_id)
2346    }
2347
2348    pub fn selections_in_range<'a>(
2349        &'a self,
2350        set_id: SelectionSetId,
2351        range: Range<DisplayPoint>,
2352        cx: &'a mut MutableAppContext,
2353    ) -> impl 'a + Iterator<Item = Range<DisplayPoint>> {
2354        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2355        let buffer = self.buffer.read(cx);
2356        let selections = self
2357            .selection_set(cx)
2358            .selections::<Point, _>(buffer)
2359            .collect::<Vec<_>>();
2360        let start = range.start.to_point(&display_map);
2361        let start_index = self.selection_insertion_index(&selections, start);
2362        let pending_selection = if set_id.replica_id == self.buffer.read(cx).replica_id() {
2363            self.pending_selection.as_ref().and_then(|pending| {
2364                let mut selection_start = pending.start.to_display_point(&display_map);
2365                let mut selection_end = pending.end.to_display_point(&display_map);
2366                if pending.reversed {
2367                    mem::swap(&mut selection_start, &mut selection_end);
2368                }
2369                if selection_start <= range.end || selection_end <= range.end {
2370                    Some(selection_start..selection_end)
2371                } else {
2372                    None
2373                }
2374            })
2375        } else {
2376            None
2377        };
2378        selections
2379            .into_iter()
2380            .skip(start_index)
2381            .map(move |s| s.display_range(&display_map))
2382            .take_while(move |r| r.start <= range.end || r.end <= range.end)
2383            .chain(pending_selection)
2384    }
2385
2386    fn selection_insertion_index(&self, selections: &[Selection<Point>], start: Point) -> usize {
2387        match selections.binary_search_by_key(&start, |probe| probe.start) {
2388            Ok(index) => index,
2389            Err(index) => {
2390                if index > 0 && selections[index - 1].end > start {
2391                    index - 1
2392                } else {
2393                    index
2394                }
2395            }
2396        }
2397    }
2398
2399    pub fn selections<'a, D>(&self, cx: &'a AppContext) -> impl 'a + Iterator<Item = Selection<D>>
2400    where
2401        D: 'a + TextDimension<'a> + Ord,
2402    {
2403        let buffer = self.buffer.read(cx);
2404        let mut selections = self.selection_set(cx).selections::<D, _>(buffer).peekable();
2405        let mut pending_selection = self.pending_selection(cx);
2406        iter::from_fn(move || {
2407            if let Some(pending) = pending_selection.as_mut() {
2408                while let Some(next_selection) = selections.peek() {
2409                    if pending.start <= next_selection.end && pending.end >= next_selection.start {
2410                        let next_selection = selections.next().unwrap();
2411                        if next_selection.start < pending.start {
2412                            pending.start = next_selection.start;
2413                        }
2414                        if next_selection.end > pending.end {
2415                            pending.end = next_selection.end;
2416                        }
2417                    } else if next_selection.end < pending.start {
2418                        return selections.next();
2419                    } else {
2420                        break;
2421                    }
2422                }
2423
2424                pending_selection.take()
2425            } else {
2426                selections.next()
2427            }
2428        })
2429    }
2430
2431    fn pending_selection<'a, D>(&self, cx: &'a AppContext) -> Option<Selection<D>>
2432    where
2433        D: 'a + TextDimension<'a>,
2434    {
2435        let buffer = self.buffer.read(cx);
2436        self.pending_selection.as_ref().map(|selection| Selection {
2437            id: selection.id,
2438            start: selection.start.summary::<D, _>(buffer),
2439            end: selection.end.summary::<D, _>(buffer),
2440            reversed: selection.reversed,
2441            goal: selection.goal,
2442        })
2443    }
2444
2445    fn selection_count<'a>(&self, cx: &'a AppContext) -> usize {
2446        let mut selection_count = self.selection_set(cx).len();
2447        if self.pending_selection.is_some() {
2448            selection_count += 1;
2449        }
2450        selection_count
2451    }
2452
2453    pub fn oldest_selection<'a, T>(&self, cx: &'a AppContext) -> Selection<T>
2454    where
2455        T: 'a + TextDimension<'a>,
2456    {
2457        let buffer = self.buffer.read(cx);
2458        self.selection_set(cx)
2459            .oldest_selection(buffer)
2460            .or_else(|| self.pending_selection(cx))
2461            .unwrap()
2462    }
2463
2464    pub fn newest_selection<'a, T>(&self, cx: &'a AppContext) -> Selection<T>
2465    where
2466        T: 'a + TextDimension<'a>,
2467    {
2468        let buffer = self.buffer.read(cx);
2469        self.pending_selection(cx)
2470            .or_else(|| self.selection_set(cx).newest_selection(buffer))
2471            .unwrap()
2472    }
2473
2474    fn selection_set<'a>(&self, cx: &'a AppContext) -> &'a SelectionSet {
2475        self.buffer
2476            .read(cx)
2477            .selection_set(self.selection_set_id)
2478            .unwrap()
2479    }
2480
2481    fn update_selections<T>(
2482        &mut self,
2483        mut selections: Vec<Selection<T>>,
2484        autoscroll: bool,
2485        cx: &mut ViewContext<Self>,
2486    ) where
2487        T: ToOffset + ToPoint + Ord + std::marker::Copy + std::fmt::Debug,
2488    {
2489        // Merge overlapping selections.
2490        let buffer = self.buffer.read(cx);
2491        let mut i = 1;
2492        while i < selections.len() {
2493            if selections[i - 1].end >= selections[i].start {
2494                let removed = selections.remove(i);
2495                if removed.start < selections[i - 1].start {
2496                    selections[i - 1].start = removed.start;
2497                }
2498                if removed.end > selections[i - 1].end {
2499                    selections[i - 1].end = removed.end;
2500                }
2501            } else {
2502                i += 1;
2503            }
2504        }
2505
2506        self.pending_selection = None;
2507        self.add_selections_state = None;
2508        self.select_larger_syntax_node_stack.clear();
2509        while let Some(autoclose_pair_state) = self.autoclose_stack.last() {
2510            let all_selections_inside_autoclose_ranges =
2511                if selections.len() == autoclose_pair_state.ranges.len() {
2512                    selections
2513                        .iter()
2514                        .zip(autoclose_pair_state.ranges.ranges::<Point, _>(buffer))
2515                        .all(|(selection, autoclose_range)| {
2516                            let head = selection.head().to_point(&*buffer);
2517                            autoclose_range.start <= head && autoclose_range.end >= head
2518                        })
2519                } else {
2520                    false
2521                };
2522
2523            if all_selections_inside_autoclose_ranges {
2524                break;
2525            } else {
2526                self.autoclose_stack.pop();
2527            }
2528        }
2529
2530        if autoscroll {
2531            self.request_autoscroll(cx);
2532        }
2533        self.pause_cursor_blinking(cx);
2534
2535        self.buffer.update(cx, |buffer, cx| {
2536            buffer
2537                .update_selection_set(self.selection_set_id, &selections, cx)
2538                .unwrap();
2539        });
2540    }
2541
2542    fn request_autoscroll(&mut self, cx: &mut ViewContext<Self>) {
2543        self.autoscroll_requested = true;
2544        cx.notify();
2545    }
2546
2547    fn start_transaction(&mut self, cx: &mut ViewContext<Self>) {
2548        self.end_selection(cx);
2549        self.buffer.update(cx, |buffer, _| {
2550            buffer
2551                .start_transaction(Some(self.selection_set_id))
2552                .unwrap()
2553        });
2554    }
2555
2556    fn end_transaction(&self, cx: &mut ViewContext<Self>) {
2557        self.buffer.update(cx, |buffer, cx| {
2558            buffer
2559                .end_transaction(Some(self.selection_set_id), cx)
2560                .unwrap()
2561        });
2562    }
2563
2564    pub fn page_up(&mut self, _: &PageUp, _: &mut ViewContext<Self>) {
2565        log::info!("Editor::page_up");
2566    }
2567
2568    pub fn page_down(&mut self, _: &PageDown, _: &mut ViewContext<Self>) {
2569        log::info!("Editor::page_down");
2570    }
2571
2572    pub fn fold(&mut self, _: &Fold, cx: &mut ViewContext<Self>) {
2573        let mut fold_ranges = Vec::new();
2574
2575        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
2576        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2577        for selection in selections {
2578            let range = selection.display_range(&display_map).sorted();
2579            let buffer_start_row = range.start.to_point(&display_map).row;
2580
2581            for row in (0..=range.end.row()).rev() {
2582                if self.is_line_foldable(&display_map, row) && !display_map.is_line_folded(row) {
2583                    let fold_range = self.foldable_range_for_line(&display_map, row);
2584                    if fold_range.end.row >= buffer_start_row {
2585                        fold_ranges.push(fold_range);
2586                        if row <= range.start.row() {
2587                            break;
2588                        }
2589                    }
2590                }
2591            }
2592        }
2593
2594        self.fold_ranges(fold_ranges, cx);
2595    }
2596
2597    pub fn unfold(&mut self, _: &Unfold, cx: &mut ViewContext<Self>) {
2598        let selections = self.selections::<Point>(cx).collect::<Vec<_>>();
2599        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2600        let buffer = self.buffer.read(cx);
2601        let ranges = selections
2602            .iter()
2603            .map(|s| {
2604                let range = s.display_range(&display_map).sorted();
2605                let mut start = range.start.to_point(&display_map);
2606                let mut end = range.end.to_point(&display_map);
2607                start.column = 0;
2608                end.column = buffer.line_len(end.row);
2609                start..end
2610            })
2611            .collect::<Vec<_>>();
2612        self.unfold_ranges(ranges, cx);
2613    }
2614
2615    fn is_line_foldable(&self, display_map: &DisplayMapSnapshot, display_row: u32) -> bool {
2616        let max_point = display_map.max_point();
2617        if display_row >= max_point.row() {
2618            false
2619        } else {
2620            let (start_indent, is_blank) = display_map.line_indent(display_row);
2621            if is_blank {
2622                false
2623            } else {
2624                for display_row in display_row + 1..=max_point.row() {
2625                    let (indent, is_blank) = display_map.line_indent(display_row);
2626                    if !is_blank {
2627                        return indent > start_indent;
2628                    }
2629                }
2630                false
2631            }
2632        }
2633    }
2634
2635    fn foldable_range_for_line(
2636        &self,
2637        display_map: &DisplayMapSnapshot,
2638        start_row: u32,
2639    ) -> Range<Point> {
2640        let max_point = display_map.max_point();
2641
2642        let (start_indent, _) = display_map.line_indent(start_row);
2643        let start = DisplayPoint::new(start_row, display_map.line_len(start_row));
2644        let mut end = None;
2645        for row in start_row + 1..=max_point.row() {
2646            let (indent, is_blank) = display_map.line_indent(row);
2647            if !is_blank && indent <= start_indent {
2648                end = Some(DisplayPoint::new(row - 1, display_map.line_len(row - 1)));
2649                break;
2650            }
2651        }
2652
2653        let end = end.unwrap_or(max_point);
2654        return start.to_point(display_map)..end.to_point(display_map);
2655    }
2656
2657    pub fn fold_selected_ranges(&mut self, _: &FoldSelectedRanges, cx: &mut ViewContext<Self>) {
2658        let selections = self.selections::<Point>(cx);
2659        let ranges = selections.map(|s| s.start..s.end).collect();
2660        self.fold_ranges(ranges, cx);
2661    }
2662
2663    fn fold_ranges<T: ToOffset>(&mut self, ranges: Vec<Range<T>>, cx: &mut ViewContext<Self>) {
2664        if !ranges.is_empty() {
2665            self.display_map.update(cx, |map, cx| map.fold(ranges, cx));
2666            self.autoscroll_requested = true;
2667            cx.notify();
2668        }
2669    }
2670
2671    fn unfold_ranges<T: ToOffset>(&mut self, ranges: Vec<Range<T>>, cx: &mut ViewContext<Self>) {
2672        if !ranges.is_empty() {
2673            self.display_map
2674                .update(cx, |map, cx| map.unfold(ranges, cx));
2675            self.autoscroll_requested = true;
2676            cx.notify();
2677        }
2678    }
2679
2680    pub fn longest_row(&self, cx: &mut MutableAppContext) -> u32 {
2681        self.display_map
2682            .update(cx, |map, cx| map.snapshot(cx))
2683            .longest_row()
2684    }
2685
2686    pub fn max_point(&self, cx: &mut MutableAppContext) -> DisplayPoint {
2687        self.display_map
2688            .update(cx, |map, cx| map.snapshot(cx))
2689            .max_point()
2690    }
2691
2692    pub fn text(&self, cx: &AppContext) -> String {
2693        self.buffer.read(cx).text()
2694    }
2695
2696    pub fn display_text(&self, cx: &mut MutableAppContext) -> String {
2697        self.display_map
2698            .update(cx, |map, cx| map.snapshot(cx))
2699            .text()
2700    }
2701
2702    // pub fn font_size(&self) -> f32 {
2703    //     self.settings.font_size
2704    // }
2705
2706    pub fn set_wrap_width(&self, width: f32, cx: &mut MutableAppContext) -> bool {
2707        self.display_map
2708            .update(cx, |map, cx| map.set_wrap_width(Some(width), cx))
2709    }
2710
2711    fn next_blink_epoch(&mut self) -> usize {
2712        self.blink_epoch += 1;
2713        self.blink_epoch
2714    }
2715
2716    fn pause_cursor_blinking(&mut self, cx: &mut ViewContext<Self>) {
2717        self.show_local_cursors = true;
2718        cx.notify();
2719
2720        let epoch = self.next_blink_epoch();
2721        cx.spawn(|this, mut cx| {
2722            let this = this.downgrade();
2723            async move {
2724                Timer::after(CURSOR_BLINK_INTERVAL).await;
2725                if let Some(this) = cx.read(|cx| this.upgrade(cx)) {
2726                    this.update(&mut cx, |this, cx| this.resume_cursor_blinking(epoch, cx))
2727                }
2728            }
2729        })
2730        .detach();
2731    }
2732
2733    fn resume_cursor_blinking(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
2734        if epoch == self.blink_epoch {
2735            self.blinking_paused = false;
2736            self.blink_cursors(epoch, cx);
2737        }
2738    }
2739
2740    fn blink_cursors(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
2741        if epoch == self.blink_epoch && self.focused && !self.blinking_paused {
2742            self.show_local_cursors = !self.show_local_cursors;
2743            cx.notify();
2744
2745            let epoch = self.next_blink_epoch();
2746            cx.spawn(|this, mut cx| {
2747                let this = this.downgrade();
2748                async move {
2749                    Timer::after(CURSOR_BLINK_INTERVAL).await;
2750                    if let Some(this) = cx.read(|cx| this.upgrade(cx)) {
2751                        this.update(&mut cx, |this, cx| this.blink_cursors(epoch, cx));
2752                    }
2753                }
2754            })
2755            .detach();
2756        }
2757    }
2758
2759    pub fn show_local_cursors(&self) -> bool {
2760        self.show_local_cursors
2761    }
2762
2763    fn on_buffer_changed(&mut self, _: ModelHandle<Buffer>, cx: &mut ViewContext<Self>) {
2764        cx.notify();
2765    }
2766
2767    fn on_buffer_event(
2768        &mut self,
2769        _: ModelHandle<Buffer>,
2770        event: &language::Event,
2771        cx: &mut ViewContext<Self>,
2772    ) {
2773        match event {
2774            language::Event::Edited => cx.emit(Event::Edited),
2775            language::Event::Dirtied => cx.emit(Event::Dirtied),
2776            language::Event::Saved => cx.emit(Event::Saved),
2777            language::Event::FileHandleChanged => cx.emit(Event::FileHandleChanged),
2778            language::Event::Reloaded => cx.emit(Event::FileHandleChanged),
2779            language::Event::Closed => cx.emit(Event::Closed),
2780            language::Event::Reparsed => {}
2781        }
2782    }
2783
2784    fn on_display_map_changed(&mut self, _: ModelHandle<DisplayMap>, cx: &mut ViewContext<Self>) {
2785        cx.notify();
2786    }
2787}
2788
2789impl Snapshot {
2790    pub fn is_empty(&self) -> bool {
2791        self.display_snapshot.is_empty()
2792    }
2793
2794    pub fn is_focused(&self) -> bool {
2795        self.is_focused
2796    }
2797
2798    pub fn placeholder_text(&self) -> Option<&Arc<str>> {
2799        self.placeholder_text.as_ref()
2800    }
2801
2802    pub fn buffer_row_count(&self) -> u32 {
2803        self.display_snapshot.buffer_row_count()
2804    }
2805
2806    pub fn buffer_rows(&self, start_row: u32) -> BufferRows {
2807        self.display_snapshot.buffer_rows(start_row)
2808    }
2809
2810    pub fn chunks<'a>(
2811        &'a self,
2812        display_rows: Range<u32>,
2813        theme: Option<&'a SyntaxTheme>,
2814    ) -> display_map::Chunks<'a> {
2815        self.display_snapshot.chunks(display_rows, theme)
2816    }
2817
2818    pub fn scroll_position(&self) -> Vector2F {
2819        compute_scroll_position(
2820            &self.display_snapshot,
2821            self.scroll_position,
2822            &self.scroll_top_anchor,
2823        )
2824    }
2825
2826    pub fn max_point(&self) -> DisplayPoint {
2827        self.display_snapshot.max_point()
2828    }
2829
2830    pub fn longest_row(&self) -> u32 {
2831        self.display_snapshot.longest_row()
2832    }
2833
2834    pub fn line_len(&self, display_row: u32) -> u32 {
2835        self.display_snapshot.line_len(display_row)
2836    }
2837
2838    pub fn line(&self, display_row: u32) -> String {
2839        self.display_snapshot.line(display_row)
2840    }
2841
2842    pub fn prev_row_boundary(&self, point: DisplayPoint) -> (DisplayPoint, Point) {
2843        self.display_snapshot.prev_row_boundary(point)
2844    }
2845
2846    pub fn next_row_boundary(&self, point: DisplayPoint) -> (DisplayPoint, Point) {
2847        self.display_snapshot.next_row_boundary(point)
2848    }
2849}
2850
2851impl EditorSettings {
2852    #[cfg(any(test, feature = "test-support"))]
2853    pub fn test(cx: &AppContext) -> Self {
2854        Self {
2855            tab_size: 4,
2856            style: {
2857                let font_cache: &gpui::FontCache = cx.font_cache();
2858                let font_family_name = Arc::from("Monaco");
2859                let font_properties = Default::default();
2860                let font_family_id = font_cache.load_family(&[&font_family_name]).unwrap();
2861                let font_id = font_cache
2862                    .select_font(font_family_id, &font_properties)
2863                    .unwrap();
2864                EditorStyle {
2865                    text: gpui::fonts::TextStyle {
2866                        font_family_name,
2867                        font_family_id,
2868                        font_id,
2869                        font_size: 14.,
2870                        color: gpui::color::Color::from_u32(0xff0000ff),
2871                        font_properties,
2872                        underline: None,
2873                    },
2874                    placeholder_text: None,
2875                    background: Default::default(),
2876                    gutter_background: Default::default(),
2877                    active_line_background: Default::default(),
2878                    line_number: Default::default(),
2879                    line_number_active: Default::default(),
2880                    selection: Default::default(),
2881                    guest_selections: Default::default(),
2882                    syntax: Default::default(),
2883                    error_underline: Default::default(),
2884                    warning_underline: Default::default(),
2885                    information_underline: Default::default(),
2886                    hint_underline: Default::default(),
2887                }
2888            },
2889        }
2890    }
2891}
2892
2893fn compute_scroll_position(
2894    snapshot: &DisplayMapSnapshot,
2895    mut scroll_position: Vector2F,
2896    scroll_top_anchor: &Anchor,
2897) -> Vector2F {
2898    let scroll_top = scroll_top_anchor.to_display_point(snapshot).row() as f32;
2899    scroll_position.set_y(scroll_top + scroll_position.y());
2900    scroll_position
2901}
2902
2903pub enum Event {
2904    Activate,
2905    Edited,
2906    Blurred,
2907    Dirtied,
2908    Saved,
2909    FileHandleChanged,
2910    Closed,
2911}
2912
2913impl Entity for Editor {
2914    type Event = Event;
2915
2916    fn release(&mut self, cx: &mut MutableAppContext) {
2917        self.buffer.update(cx, |buffer, cx| {
2918            buffer
2919                .remove_selection_set(self.selection_set_id, cx)
2920                .unwrap();
2921        });
2922    }
2923}
2924
2925impl View for Editor {
2926    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
2927        let settings = self.build_settings.borrow_mut()(cx);
2928        self.display_map.update(cx, |map, cx| {
2929            map.set_font(
2930                settings.style.text.font_id,
2931                settings.style.text.font_size,
2932                cx,
2933            )
2934        });
2935        EditorElement::new(self.handle.clone(), settings).boxed()
2936    }
2937
2938    fn ui_name() -> &'static str {
2939        "Editor"
2940    }
2941
2942    fn on_focus(&mut self, cx: &mut ViewContext<Self>) {
2943        self.focused = true;
2944        self.blink_cursors(self.blink_epoch, cx);
2945        self.buffer.update(cx, |buffer, cx| {
2946            buffer
2947                .set_active_selection_set(Some(self.selection_set_id), cx)
2948                .unwrap();
2949        });
2950    }
2951
2952    fn on_blur(&mut self, cx: &mut ViewContext<Self>) {
2953        self.focused = false;
2954        self.show_local_cursors = false;
2955        self.buffer.update(cx, |buffer, cx| {
2956            buffer.set_active_selection_set(None, cx).unwrap();
2957        });
2958        cx.emit(Event::Blurred);
2959        cx.notify();
2960    }
2961
2962    fn keymap_context(&self, _: &AppContext) -> gpui::keymap::Context {
2963        let mut cx = Self::default_keymap_context();
2964        let mode = match self.mode {
2965            EditorMode::SingleLine => "single_line",
2966            EditorMode::AutoHeight { .. } => "auto_height",
2967            EditorMode::Full => "full",
2968        };
2969        cx.map.insert("mode".into(), mode.into());
2970        cx
2971    }
2972}
2973
2974impl SelectionExt for Selection<Point> {
2975    fn display_range(&self, map: &DisplayMapSnapshot) -> Range<DisplayPoint> {
2976        let start = self.start.to_display_point(map);
2977        let end = self.end.to_display_point(map);
2978        if self.reversed {
2979            end..start
2980        } else {
2981            start..end
2982        }
2983    }
2984
2985    fn spanned_rows(
2986        &self,
2987        include_end_if_at_line_start: bool,
2988        map: &DisplayMapSnapshot,
2989    ) -> SpannedRows {
2990        let display_start = self.start.to_display_point(map);
2991        let mut display_end = self.end.to_display_point(map);
2992        if !include_end_if_at_line_start
2993            && display_end.row() != map.max_point().row()
2994            && display_start.row() != display_end.row()
2995            && display_end.column() == 0
2996        {
2997            *display_end.row_mut() -= 1;
2998        }
2999
3000        let (display_start, buffer_start) = map.prev_row_boundary(display_start);
3001        let (display_end, buffer_end) = map.next_row_boundary(display_end);
3002
3003        SpannedRows {
3004            buffer_rows: buffer_start.row..buffer_end.row + 1,
3005            display_rows: display_start.row()..display_end.row() + 1,
3006        }
3007    }
3008}
3009
3010#[cfg(test)]
3011mod tests {
3012    use super::*;
3013    use crate::test::sample_text;
3014    use buffer::Point;
3015    use unindent::Unindent;
3016
3017    #[gpui::test]
3018    fn test_selection_with_mouse(cx: &mut gpui::MutableAppContext) {
3019        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
3020        let settings = EditorSettings::test(cx);
3021        let (_, editor) =
3022            cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3023
3024        editor.update(cx, |view, cx| {
3025            view.begin_selection(DisplayPoint::new(2, 2), false, cx);
3026        });
3027
3028        assert_eq!(
3029            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3030            [DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2)]
3031        );
3032
3033        editor.update(cx, |view, cx| {
3034            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
3035        });
3036
3037        assert_eq!(
3038            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3039            [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
3040        );
3041
3042        editor.update(cx, |view, cx| {
3043            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
3044        });
3045
3046        assert_eq!(
3047            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3048            [DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1)]
3049        );
3050
3051        editor.update(cx, |view, cx| {
3052            view.end_selection(cx);
3053            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
3054        });
3055
3056        assert_eq!(
3057            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3058            [DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1)]
3059        );
3060
3061        editor.update(cx, |view, cx| {
3062            view.begin_selection(DisplayPoint::new(3, 3), true, cx);
3063            view.update_selection(DisplayPoint::new(0, 0), Vector2F::zero(), cx);
3064        });
3065
3066        assert_eq!(
3067            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3068            [
3069                DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1),
3070                DisplayPoint::new(3, 3)..DisplayPoint::new(0, 0)
3071            ]
3072        );
3073
3074        editor.update(cx, |view, cx| {
3075            view.end_selection(cx);
3076        });
3077
3078        assert_eq!(
3079            editor.update(cx, |view, cx| view.selection_ranges(cx)),
3080            [DisplayPoint::new(3, 3)..DisplayPoint::new(0, 0)]
3081        );
3082    }
3083
3084    #[gpui::test]
3085    fn test_canceling_pending_selection(cx: &mut gpui::MutableAppContext) {
3086        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
3087        let settings = EditorSettings::test(cx);
3088        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3089
3090        view.update(cx, |view, cx| {
3091            view.begin_selection(DisplayPoint::new(2, 2), false, cx);
3092            assert_eq!(
3093                view.selection_ranges(cx),
3094                [DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2)]
3095            );
3096        });
3097
3098        view.update(cx, |view, cx| {
3099            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
3100            assert_eq!(
3101                view.selection_ranges(cx),
3102                [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
3103            );
3104        });
3105
3106        view.update(cx, |view, cx| {
3107            view.cancel(&Cancel, cx);
3108            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
3109            assert_eq!(
3110                view.selection_ranges(cx),
3111                [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
3112            );
3113        });
3114    }
3115
3116    #[gpui::test]
3117    fn test_cancel(cx: &mut gpui::MutableAppContext) {
3118        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
3119        let settings = EditorSettings::test(cx);
3120        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3121
3122        view.update(cx, |view, cx| {
3123            view.begin_selection(DisplayPoint::new(3, 4), false, cx);
3124            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
3125            view.end_selection(cx);
3126
3127            view.begin_selection(DisplayPoint::new(0, 1), true, cx);
3128            view.update_selection(DisplayPoint::new(0, 3), Vector2F::zero(), cx);
3129            view.end_selection(cx);
3130            assert_eq!(
3131                view.selection_ranges(cx),
3132                [
3133                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
3134                    DisplayPoint::new(3, 4)..DisplayPoint::new(1, 1),
3135                ]
3136            );
3137        });
3138
3139        view.update(cx, |view, cx| {
3140            view.cancel(&Cancel, cx);
3141            assert_eq!(
3142                view.selection_ranges(cx),
3143                [DisplayPoint::new(3, 4)..DisplayPoint::new(1, 1)]
3144            );
3145        });
3146
3147        view.update(cx, |view, cx| {
3148            view.cancel(&Cancel, cx);
3149            assert_eq!(
3150                view.selection_ranges(cx),
3151                [DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1)]
3152            );
3153        });
3154    }
3155
3156    #[gpui::test]
3157    fn test_fold(cx: &mut gpui::MutableAppContext) {
3158        let buffer = cx.add_model(|cx| {
3159            Buffer::new(
3160                0,
3161                "
3162                    impl Foo {
3163                        // Hello!
3164
3165                        fn a() {
3166                            1
3167                        }
3168
3169                        fn b() {
3170                            2
3171                        }
3172
3173                        fn c() {
3174                            3
3175                        }
3176                    }
3177                "
3178                .unindent(),
3179                cx,
3180            )
3181        });
3182        let settings = EditorSettings::test(&cx);
3183        let (_, view) = cx.add_window(Default::default(), |cx| {
3184            build_editor(buffer.clone(), settings, cx)
3185        });
3186
3187        view.update(cx, |view, cx| {
3188            view.select_display_ranges(&[DisplayPoint::new(8, 0)..DisplayPoint::new(12, 0)], cx)
3189                .unwrap();
3190            view.fold(&Fold, cx);
3191            assert_eq!(
3192                view.display_text(cx),
3193                "
3194                    impl Foo {
3195                        // Hello!
3196
3197                        fn a() {
3198                            1
3199                        }
3200
3201                        fn b() {…
3202                        }
3203
3204                        fn c() {…
3205                        }
3206                    }
3207                "
3208                .unindent(),
3209            );
3210
3211            view.fold(&Fold, cx);
3212            assert_eq!(
3213                view.display_text(cx),
3214                "
3215                    impl Foo {…
3216                    }
3217                "
3218                .unindent(),
3219            );
3220
3221            view.unfold(&Unfold, cx);
3222            assert_eq!(
3223                view.display_text(cx),
3224                "
3225                    impl Foo {
3226                        // Hello!
3227
3228                        fn a() {
3229                            1
3230                        }
3231
3232                        fn b() {…
3233                        }
3234
3235                        fn c() {…
3236                        }
3237                    }
3238                "
3239                .unindent(),
3240            );
3241
3242            view.unfold(&Unfold, cx);
3243            assert_eq!(view.display_text(cx), buffer.read(cx).text());
3244        });
3245    }
3246
3247    #[gpui::test]
3248    fn test_move_cursor(cx: &mut gpui::MutableAppContext) {
3249        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 6), cx));
3250        let settings = EditorSettings::test(&cx);
3251        let (_, view) = cx.add_window(Default::default(), |cx| {
3252            build_editor(buffer.clone(), settings, cx)
3253        });
3254
3255        buffer.update(cx, |buffer, cx| {
3256            buffer.edit(
3257                vec![
3258                    Point::new(1, 0)..Point::new(1, 0),
3259                    Point::new(1, 1)..Point::new(1, 1),
3260                ],
3261                "\t",
3262                cx,
3263            );
3264        });
3265
3266        view.update(cx, |view, cx| {
3267            assert_eq!(
3268                view.selection_ranges(cx),
3269                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
3270            );
3271
3272            view.move_down(&MoveDown, cx);
3273            assert_eq!(
3274                view.selection_ranges(cx),
3275                &[DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0)]
3276            );
3277
3278            view.move_right(&MoveRight, cx);
3279            assert_eq!(
3280                view.selection_ranges(cx),
3281                &[DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4)]
3282            );
3283
3284            view.move_left(&MoveLeft, cx);
3285            assert_eq!(
3286                view.selection_ranges(cx),
3287                &[DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0)]
3288            );
3289
3290            view.move_up(&MoveUp, cx);
3291            assert_eq!(
3292                view.selection_ranges(cx),
3293                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
3294            );
3295
3296            view.move_to_end(&MoveToEnd, cx);
3297            assert_eq!(
3298                view.selection_ranges(cx),
3299                &[DisplayPoint::new(5, 6)..DisplayPoint::new(5, 6)]
3300            );
3301
3302            view.move_to_beginning(&MoveToBeginning, cx);
3303            assert_eq!(
3304                view.selection_ranges(cx),
3305                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
3306            );
3307
3308            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 2)], cx)
3309                .unwrap();
3310            view.select_to_beginning(&SelectToBeginning, cx);
3311            assert_eq!(
3312                view.selection_ranges(cx),
3313                &[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 0)]
3314            );
3315
3316            view.select_to_end(&SelectToEnd, cx);
3317            assert_eq!(
3318                view.selection_ranges(cx),
3319                &[DisplayPoint::new(0, 1)..DisplayPoint::new(5, 6)]
3320            );
3321        });
3322    }
3323
3324    #[gpui::test]
3325    fn test_move_cursor_multibyte(cx: &mut gpui::MutableAppContext) {
3326        let buffer = cx.add_model(|cx| Buffer::new(0, "ⓐⓑⓒⓓⓔ\nabcde\nαβγδε\n", cx));
3327        let settings = EditorSettings::test(&cx);
3328        let (_, view) = cx.add_window(Default::default(), |cx| {
3329            build_editor(buffer.clone(), settings, cx)
3330        });
3331
3332        assert_eq!('ⓐ'.len_utf8(), 3);
3333        assert_eq!('α'.len_utf8(), 2);
3334
3335        view.update(cx, |view, cx| {
3336            view.fold_ranges(
3337                vec![
3338                    Point::new(0, 6)..Point::new(0, 12),
3339                    Point::new(1, 2)..Point::new(1, 4),
3340                    Point::new(2, 4)..Point::new(2, 8),
3341                ],
3342                cx,
3343            );
3344            assert_eq!(view.display_text(cx), "ⓐⓑ…ⓔ\nab…e\nαβ…ε\n");
3345
3346            view.move_right(&MoveRight, cx);
3347            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "".len())]);
3348            view.move_right(&MoveRight, cx);
3349            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ".len())]);
3350            view.move_right(&MoveRight, cx);
3351            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…".len())]);
3352
3353            view.move_down(&MoveDown, cx);
3354            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab…".len())]);
3355            view.move_left(&MoveLeft, cx);
3356            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab".len())]);
3357            view.move_left(&MoveLeft, cx);
3358            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "a".len())]);
3359
3360            view.move_down(&MoveDown, cx);
3361            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "α".len())]);
3362            view.move_right(&MoveRight, cx);
3363            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ".len())]);
3364            view.move_right(&MoveRight, cx);
3365            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ…".len())]);
3366            view.move_right(&MoveRight, cx);
3367            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ…ε".len())]);
3368
3369            view.move_up(&MoveUp, cx);
3370            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab…e".len())]);
3371            view.move_up(&MoveUp, cx);
3372            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…ⓔ".len())]);
3373            view.move_left(&MoveLeft, cx);
3374            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…".len())]);
3375            view.move_left(&MoveLeft, cx);
3376            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ".len())]);
3377            view.move_left(&MoveLeft, cx);
3378            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "".len())]);
3379        });
3380    }
3381
3382    #[gpui::test]
3383    fn test_move_cursor_different_line_lengths(cx: &mut gpui::MutableAppContext) {
3384        let buffer = cx.add_model(|cx| Buffer::new(0, "ⓐⓑⓒⓓⓔ\nabcd\nαβγ\nabcd\nⓐⓑⓒⓓⓔ\n", cx));
3385        let settings = EditorSettings::test(&cx);
3386        let (_, view) = cx.add_window(Default::default(), |cx| {
3387            build_editor(buffer.clone(), settings, cx)
3388        });
3389        view.update(cx, |view, cx| {
3390            view.select_display_ranges(&[empty_range(0, "ⓐⓑⓒⓓⓔ".len())], cx)
3391                .unwrap();
3392
3393            view.move_down(&MoveDown, cx);
3394            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "abcd".len())]);
3395
3396            view.move_down(&MoveDown, cx);
3397            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβγ".len())]);
3398
3399            view.move_down(&MoveDown, cx);
3400            assert_eq!(view.selection_ranges(cx), &[empty_range(3, "abcd".len())]);
3401
3402            view.move_down(&MoveDown, cx);
3403            assert_eq!(view.selection_ranges(cx), &[empty_range(4, "ⓐⓑⓒⓓⓔ".len())]);
3404
3405            view.move_up(&MoveUp, cx);
3406            assert_eq!(view.selection_ranges(cx), &[empty_range(3, "abcd".len())]);
3407
3408            view.move_up(&MoveUp, cx);
3409            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβγ".len())]);
3410        });
3411    }
3412
3413    #[gpui::test]
3414    fn test_beginning_end_of_line(cx: &mut gpui::MutableAppContext) {
3415        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\n  def", cx));
3416        let settings = EditorSettings::test(&cx);
3417        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3418        view.update(cx, |view, cx| {
3419            view.select_display_ranges(
3420                &[
3421                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3422                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4),
3423                ],
3424                cx,
3425            )
3426            .unwrap();
3427        });
3428
3429        view.update(cx, |view, cx| {
3430            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3431            assert_eq!(
3432                view.selection_ranges(cx),
3433                &[
3434                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3435                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3436                ]
3437            );
3438        });
3439
3440        view.update(cx, |view, cx| {
3441            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3442            assert_eq!(
3443                view.selection_ranges(cx),
3444                &[
3445                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3446                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3447                ]
3448            );
3449        });
3450
3451        view.update(cx, |view, cx| {
3452            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3453            assert_eq!(
3454                view.selection_ranges(cx),
3455                &[
3456                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3457                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3458                ]
3459            );
3460        });
3461
3462        view.update(cx, |view, cx| {
3463            view.move_to_end_of_line(&MoveToEndOfLine, cx);
3464            assert_eq!(
3465                view.selection_ranges(cx),
3466                &[
3467                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3468                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
3469                ]
3470            );
3471        });
3472
3473        // Moving to the end of line again is a no-op.
3474        view.update(cx, |view, cx| {
3475            view.move_to_end_of_line(&MoveToEndOfLine, cx);
3476            assert_eq!(
3477                view.selection_ranges(cx),
3478                &[
3479                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3480                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
3481                ]
3482            );
3483        });
3484
3485        view.update(cx, |view, cx| {
3486            view.move_left(&MoveLeft, cx);
3487            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3488            assert_eq!(
3489                view.selection_ranges(cx),
3490                &[
3491                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3492                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 2),
3493                ]
3494            );
3495        });
3496
3497        view.update(cx, |view, cx| {
3498            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3499            assert_eq!(
3500                view.selection_ranges(cx),
3501                &[
3502                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3503                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 0),
3504                ]
3505            );
3506        });
3507
3508        view.update(cx, |view, cx| {
3509            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3510            assert_eq!(
3511                view.selection_ranges(cx),
3512                &[
3513                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3514                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 2),
3515                ]
3516            );
3517        });
3518
3519        view.update(cx, |view, cx| {
3520            view.select_to_end_of_line(&SelectToEndOfLine, cx);
3521            assert_eq!(
3522                view.selection_ranges(cx),
3523                &[
3524                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 3),
3525                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 5),
3526                ]
3527            );
3528        });
3529
3530        view.update(cx, |view, cx| {
3531            view.delete_to_end_of_line(&DeleteToEndOfLine, cx);
3532            assert_eq!(view.display_text(cx), "ab\n  de");
3533            assert_eq!(
3534                view.selection_ranges(cx),
3535                &[
3536                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3537                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4),
3538                ]
3539            );
3540        });
3541
3542        view.update(cx, |view, cx| {
3543            view.delete_to_beginning_of_line(&DeleteToBeginningOfLine, cx);
3544            assert_eq!(view.display_text(cx), "\n");
3545            assert_eq!(
3546                view.selection_ranges(cx),
3547                &[
3548                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3549                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3550                ]
3551            );
3552        });
3553    }
3554
3555    #[gpui::test]
3556    fn test_prev_next_word_boundary(cx: &mut gpui::MutableAppContext) {
3557        let buffer =
3558            cx.add_model(|cx| Buffer::new(0, "use std::str::{foo, bar}\n\n  {baz.qux()}", cx));
3559        let settings = EditorSettings::test(&cx);
3560        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3561        view.update(cx, |view, cx| {
3562            view.select_display_ranges(
3563                &[
3564                    DisplayPoint::new(0, 11)..DisplayPoint::new(0, 11),
3565                    DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4),
3566                ],
3567                cx,
3568            )
3569            .unwrap();
3570        });
3571
3572        view.update(cx, |view, cx| {
3573            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3574            assert_eq!(
3575                view.selection_ranges(cx),
3576                &[
3577                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 9),
3578                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 3),
3579                ]
3580            );
3581        });
3582
3583        view.update(cx, |view, cx| {
3584            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3585            assert_eq!(
3586                view.selection_ranges(cx),
3587                &[
3588                    DisplayPoint::new(0, 7)..DisplayPoint::new(0, 7),
3589                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2),
3590                ]
3591            );
3592        });
3593
3594        view.update(cx, |view, cx| {
3595            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3596            assert_eq!(
3597                view.selection_ranges(cx),
3598                &[
3599                    DisplayPoint::new(0, 4)..DisplayPoint::new(0, 4),
3600                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 0),
3601                ]
3602            );
3603        });
3604
3605        view.update(cx, |view, cx| {
3606            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3607            assert_eq!(
3608                view.selection_ranges(cx),
3609                &[
3610                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3611                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3612                ]
3613            );
3614        });
3615
3616        view.update(cx, |view, cx| {
3617            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3618            assert_eq!(
3619                view.selection_ranges(cx),
3620                &[
3621                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3622                    DisplayPoint::new(0, 23)..DisplayPoint::new(0, 23),
3623                ]
3624            );
3625        });
3626
3627        view.update(cx, |view, cx| {
3628            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3629            assert_eq!(
3630                view.selection_ranges(cx),
3631                &[
3632                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3633                    DisplayPoint::new(0, 24)..DisplayPoint::new(0, 24),
3634                ]
3635            );
3636        });
3637
3638        view.update(cx, |view, cx| {
3639            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3640            assert_eq!(
3641                view.selection_ranges(cx),
3642                &[
3643                    DisplayPoint::new(0, 7)..DisplayPoint::new(0, 7),
3644                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3645                ]
3646            );
3647        });
3648
3649        view.update(cx, |view, cx| {
3650            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3651            assert_eq!(
3652                view.selection_ranges(cx),
3653                &[
3654                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 9),
3655                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 3),
3656                ]
3657            );
3658        });
3659
3660        view.update(cx, |view, cx| {
3661            view.move_right(&MoveRight, cx);
3662            view.select_to_previous_word_boundary(&SelectToPreviousWordBoundary, cx);
3663            assert_eq!(
3664                view.selection_ranges(cx),
3665                &[
3666                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 9),
3667                    DisplayPoint::new(2, 4)..DisplayPoint::new(2, 3),
3668                ]
3669            );
3670        });
3671
3672        view.update(cx, |view, cx| {
3673            view.select_to_previous_word_boundary(&SelectToPreviousWordBoundary, cx);
3674            assert_eq!(
3675                view.selection_ranges(cx),
3676                &[
3677                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 7),
3678                    DisplayPoint::new(2, 4)..DisplayPoint::new(2, 2),
3679                ]
3680            );
3681        });
3682
3683        view.update(cx, |view, cx| {
3684            view.select_to_next_word_boundary(&SelectToNextWordBoundary, cx);
3685            assert_eq!(
3686                view.selection_ranges(cx),
3687                &[
3688                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 9),
3689                    DisplayPoint::new(2, 4)..DisplayPoint::new(2, 3),
3690                ]
3691            );
3692        });
3693    }
3694
3695    #[gpui::test]
3696    fn test_prev_next_word_bounds_with_soft_wrap(cx: &mut gpui::MutableAppContext) {
3697        let buffer =
3698            cx.add_model(|cx| Buffer::new(0, "use one::{\n    two::three::four::five\n};", cx));
3699        let settings = EditorSettings::test(&cx);
3700        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3701
3702        view.update(cx, |view, cx| {
3703            view.set_wrap_width(140., cx);
3704            assert_eq!(
3705                view.display_text(cx),
3706                "use one::{\n    two::three::\n    four::five\n};"
3707            );
3708
3709            view.select_display_ranges(&[DisplayPoint::new(1, 7)..DisplayPoint::new(1, 7)], cx)
3710                .unwrap();
3711
3712            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3713            assert_eq!(
3714                view.selection_ranges(cx),
3715                &[DisplayPoint::new(1, 9)..DisplayPoint::new(1, 9)]
3716            );
3717
3718            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3719            assert_eq!(
3720                view.selection_ranges(cx),
3721                &[DisplayPoint::new(1, 14)..DisplayPoint::new(1, 14)]
3722            );
3723
3724            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3725            assert_eq!(
3726                view.selection_ranges(cx),
3727                &[DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4)]
3728            );
3729
3730            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3731            assert_eq!(
3732                view.selection_ranges(cx),
3733                &[DisplayPoint::new(2, 8)..DisplayPoint::new(2, 8)]
3734            );
3735
3736            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3737            assert_eq!(
3738                view.selection_ranges(cx),
3739                &[DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4)]
3740            );
3741
3742            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3743            assert_eq!(
3744                view.selection_ranges(cx),
3745                &[DisplayPoint::new(1, 14)..DisplayPoint::new(1, 14)]
3746            );
3747        });
3748    }
3749
3750    #[gpui::test]
3751    fn test_delete_to_word_boundary(cx: &mut gpui::MutableAppContext) {
3752        let buffer = cx.add_model(|cx| Buffer::new(0, "one two three four", cx));
3753        let settings = EditorSettings::test(&cx);
3754        let (_, view) = cx.add_window(Default::default(), |cx| {
3755            build_editor(buffer.clone(), settings, cx)
3756        });
3757
3758        view.update(cx, |view, cx| {
3759            view.select_display_ranges(
3760                &[
3761                    // an empty selection - the preceding word fragment is deleted
3762                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3763                    // characters selected - they are deleted
3764                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 12),
3765                ],
3766                cx,
3767            )
3768            .unwrap();
3769            view.delete_to_previous_word_boundary(&DeleteToPreviousWordBoundary, cx);
3770        });
3771
3772        assert_eq!(buffer.read(cx).text(), "e two te four");
3773
3774        view.update(cx, |view, cx| {
3775            view.select_display_ranges(
3776                &[
3777                    // an empty selection - the following word fragment is deleted
3778                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3779                    // characters selected - they are deleted
3780                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 10),
3781                ],
3782                cx,
3783            )
3784            .unwrap();
3785            view.delete_to_next_word_boundary(&DeleteToNextWordBoundary, cx);
3786        });
3787
3788        assert_eq!(buffer.read(cx).text(), "e t te our");
3789    }
3790
3791    #[gpui::test]
3792    fn test_newline(cx: &mut gpui::MutableAppContext) {
3793        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaa\n    bbbb\n", cx));
3794        let settings = EditorSettings::test(&cx);
3795        let (_, view) = cx.add_window(Default::default(), |cx| {
3796            build_editor(buffer.clone(), settings, cx)
3797        });
3798
3799        view.update(cx, |view, cx| {
3800            view.select_display_ranges(
3801                &[
3802                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3803                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3804                    DisplayPoint::new(1, 6)..DisplayPoint::new(1, 6),
3805                ],
3806                cx,
3807            )
3808            .unwrap();
3809
3810            view.newline(&Newline, cx);
3811            assert_eq!(view.text(cx), "aa\naa\n  \n    bb\n    bb\n");
3812        });
3813    }
3814
3815    #[gpui::test]
3816    fn test_backspace(cx: &mut gpui::MutableAppContext) {
3817        let buffer = cx.add_model(|cx| {
3818            Buffer::new(
3819                0,
3820                "one two three\nfour five six\nseven eight nine\nten\n",
3821                cx,
3822            )
3823        });
3824        let settings = EditorSettings::test(&cx);
3825        let (_, view) = cx.add_window(Default::default(), |cx| {
3826            build_editor(buffer.clone(), settings, cx)
3827        });
3828
3829        view.update(cx, |view, cx| {
3830            view.select_display_ranges(
3831                &[
3832                    // an empty selection - the preceding character is deleted
3833                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3834                    // one character selected - it is deleted
3835                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
3836                    // a line suffix selected - it is deleted
3837                    DisplayPoint::new(2, 6)..DisplayPoint::new(3, 0),
3838                ],
3839                cx,
3840            )
3841            .unwrap();
3842            view.backspace(&Backspace, cx);
3843        });
3844
3845        assert_eq!(
3846            buffer.read(cx).text(),
3847            "oe two three\nfou five six\nseven ten\n"
3848        );
3849    }
3850
3851    #[gpui::test]
3852    fn test_delete(cx: &mut gpui::MutableAppContext) {
3853        let buffer = cx.add_model(|cx| {
3854            Buffer::new(
3855                0,
3856                "one two three\nfour five six\nseven eight nine\nten\n",
3857                cx,
3858            )
3859        });
3860        let settings = EditorSettings::test(&cx);
3861        let (_, view) = cx.add_window(Default::default(), |cx| {
3862            build_editor(buffer.clone(), settings, cx)
3863        });
3864
3865        view.update(cx, |view, cx| {
3866            view.select_display_ranges(
3867                &[
3868                    // an empty selection - the following character is deleted
3869                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3870                    // one character selected - it is deleted
3871                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
3872                    // a line suffix selected - it is deleted
3873                    DisplayPoint::new(2, 6)..DisplayPoint::new(3, 0),
3874                ],
3875                cx,
3876            )
3877            .unwrap();
3878            view.delete(&Delete, cx);
3879        });
3880
3881        assert_eq!(
3882            buffer.read(cx).text(),
3883            "on two three\nfou five six\nseven ten\n"
3884        );
3885    }
3886
3887    #[gpui::test]
3888    fn test_delete_line(cx: &mut gpui::MutableAppContext) {
3889        let settings = EditorSettings::test(&cx);
3890        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3891        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3892        view.update(cx, |view, cx| {
3893            view.select_display_ranges(
3894                &[
3895                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3896                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 1),
3897                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3898                ],
3899                cx,
3900            )
3901            .unwrap();
3902            view.delete_line(&DeleteLine, cx);
3903            assert_eq!(view.display_text(cx), "ghi");
3904            assert_eq!(
3905                view.selection_ranges(cx),
3906                vec![
3907                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3908                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)
3909                ]
3910            );
3911        });
3912
3913        let settings = EditorSettings::test(&cx);
3914        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3915        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3916        view.update(cx, |view, cx| {
3917            view.select_display_ranges(&[DisplayPoint::new(2, 0)..DisplayPoint::new(0, 1)], cx)
3918                .unwrap();
3919            view.delete_line(&DeleteLine, cx);
3920            assert_eq!(view.display_text(cx), "ghi\n");
3921            assert_eq!(
3922                view.selection_ranges(cx),
3923                vec![DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)]
3924            );
3925        });
3926    }
3927
3928    #[gpui::test]
3929    fn test_duplicate_line(cx: &mut gpui::MutableAppContext) {
3930        let settings = EditorSettings::test(&cx);
3931        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3932        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3933        view.update(cx, |view, cx| {
3934            view.select_display_ranges(
3935                &[
3936                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
3937                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3938                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3939                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3940                ],
3941                cx,
3942            )
3943            .unwrap();
3944            view.duplicate_line(&DuplicateLine, cx);
3945            assert_eq!(view.display_text(cx), "abc\nabc\ndef\ndef\nghi\n\n");
3946            assert_eq!(
3947                view.selection_ranges(cx),
3948                vec![
3949                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 1),
3950                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3951                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3952                    DisplayPoint::new(6, 0)..DisplayPoint::new(6, 0),
3953                ]
3954            );
3955        });
3956
3957        let settings = EditorSettings::test(&cx);
3958        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3959        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3960        view.update(cx, |view, cx| {
3961            view.select_display_ranges(
3962                &[
3963                    DisplayPoint::new(0, 1)..DisplayPoint::new(1, 1),
3964                    DisplayPoint::new(1, 2)..DisplayPoint::new(2, 1),
3965                ],
3966                cx,
3967            )
3968            .unwrap();
3969            view.duplicate_line(&DuplicateLine, cx);
3970            assert_eq!(view.display_text(cx), "abc\ndef\nghi\nabc\ndef\nghi\n");
3971            assert_eq!(
3972                view.selection_ranges(cx),
3973                vec![
3974                    DisplayPoint::new(3, 1)..DisplayPoint::new(4, 1),
3975                    DisplayPoint::new(4, 2)..DisplayPoint::new(5, 1),
3976                ]
3977            );
3978        });
3979    }
3980
3981    #[gpui::test]
3982    fn test_move_line_up_down(cx: &mut gpui::MutableAppContext) {
3983        let settings = EditorSettings::test(&cx);
3984        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(10, 5), cx));
3985        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
3986        view.update(cx, |view, cx| {
3987            view.fold_ranges(
3988                vec![
3989                    Point::new(0, 2)..Point::new(1, 2),
3990                    Point::new(2, 3)..Point::new(4, 1),
3991                    Point::new(7, 0)..Point::new(8, 4),
3992                ],
3993                cx,
3994            );
3995            view.select_display_ranges(
3996                &[
3997                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3998                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
3999                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
4000                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2),
4001                ],
4002                cx,
4003            )
4004            .unwrap();
4005            assert_eq!(
4006                view.display_text(cx),
4007                "aa…bbb\nccc…eeee\nfffff\nggggg\n…i\njjjjj"
4008            );
4009
4010            view.move_line_up(&MoveLineUp, cx);
4011            assert_eq!(
4012                view.display_text(cx),
4013                "aa…bbb\nccc…eeee\nggggg\n…i\njjjjj\nfffff"
4014            );
4015            assert_eq!(
4016                view.selection_ranges(cx),
4017                vec![
4018                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4019                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4020                    DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3),
4021                    DisplayPoint::new(4, 0)..DisplayPoint::new(4, 2)
4022                ]
4023            );
4024        });
4025
4026        view.update(cx, |view, cx| {
4027            view.move_line_down(&MoveLineDown, cx);
4028            assert_eq!(
4029                view.display_text(cx),
4030                "ccc…eeee\naa…bbb\nfffff\nggggg\n…i\njjjjj"
4031            );
4032            assert_eq!(
4033                view.selection_ranges(cx),
4034                vec![
4035                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
4036                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
4037                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
4038                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2)
4039                ]
4040            );
4041        });
4042
4043        view.update(cx, |view, cx| {
4044            view.move_line_down(&MoveLineDown, cx);
4045            assert_eq!(
4046                view.display_text(cx),
4047                "ccc…eeee\nfffff\naa…bbb\nggggg\n…i\njjjjj"
4048            );
4049            assert_eq!(
4050                view.selection_ranges(cx),
4051                vec![
4052                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4053                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
4054                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
4055                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2)
4056                ]
4057            );
4058        });
4059
4060        view.update(cx, |view, cx| {
4061            view.move_line_up(&MoveLineUp, cx);
4062            assert_eq!(
4063                view.display_text(cx),
4064                "ccc…eeee\naa…bbb\nggggg\n…i\njjjjj\nfffff"
4065            );
4066            assert_eq!(
4067                view.selection_ranges(cx),
4068                vec![
4069                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
4070                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4071                    DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3),
4072                    DisplayPoint::new(4, 0)..DisplayPoint::new(4, 2)
4073                ]
4074            );
4075        });
4076    }
4077
4078    #[gpui::test]
4079    fn test_clipboard(cx: &mut gpui::MutableAppContext) {
4080        let buffer = cx.add_model(|cx| Buffer::new(0, "one✅ two three four five six ", cx));
4081        let settings = EditorSettings::test(&cx);
4082        let view = cx
4083            .add_window(Default::default(), |cx| {
4084                build_editor(buffer.clone(), settings, cx)
4085            })
4086            .1;
4087
4088        // Cut with three selections. Clipboard text is divided into three slices.
4089        view.update(cx, |view, cx| {
4090            view.select_ranges(vec![0..7, 11..17, 22..27], false, cx);
4091            view.cut(&Cut, cx);
4092            assert_eq!(view.display_text(cx), "two four six ");
4093        });
4094
4095        // Paste with three cursors. Each cursor pastes one slice of the clipboard text.
4096        view.update(cx, |view, cx| {
4097            view.select_ranges(vec![4..4, 9..9, 13..13], false, cx);
4098            view.paste(&Paste, cx);
4099            assert_eq!(view.display_text(cx), "two one✅ four three six five ");
4100            assert_eq!(
4101                view.selection_ranges(cx),
4102                &[
4103                    DisplayPoint::new(0, 11)..DisplayPoint::new(0, 11),
4104                    DisplayPoint::new(0, 22)..DisplayPoint::new(0, 22),
4105                    DisplayPoint::new(0, 31)..DisplayPoint::new(0, 31)
4106                ]
4107            );
4108        });
4109
4110        // Paste again but with only two cursors. Since the number of cursors doesn't
4111        // match the number of slices in the clipboard, the entire clipboard text
4112        // is pasted at each cursor.
4113        view.update(cx, |view, cx| {
4114            view.select_ranges(vec![0..0, 31..31], false, cx);
4115            view.handle_input(&Input("( ".into()), cx);
4116            view.paste(&Paste, cx);
4117            view.handle_input(&Input(") ".into()), cx);
4118            assert_eq!(
4119                view.display_text(cx),
4120                "( one✅ three five ) two one✅ four three six five ( one✅ three five ) "
4121            );
4122        });
4123
4124        view.update(cx, |view, cx| {
4125            view.select_ranges(vec![0..0], false, cx);
4126            view.handle_input(&Input("123\n4567\n89\n".into()), cx);
4127            assert_eq!(
4128                view.display_text(cx),
4129                "123\n4567\n89\n( one✅ three five ) two one✅ four three six five ( one✅ three five ) "
4130            );
4131        });
4132
4133        // Cut with three selections, one of which is full-line.
4134        view.update(cx, |view, cx| {
4135            view.select_display_ranges(
4136                &[
4137                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 2),
4138                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
4139                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 1),
4140                ],
4141                cx,
4142            )
4143            .unwrap();
4144            view.cut(&Cut, cx);
4145            assert_eq!(
4146                view.display_text(cx),
4147                "13\n9\n( one✅ three five ) two one✅ four three six five ( one✅ three five ) "
4148            );
4149        });
4150
4151        // Paste with three selections, noticing how the copied selection that was full-line
4152        // gets inserted before the second cursor.
4153        view.update(cx, |view, cx| {
4154            view.select_display_ranges(
4155                &[
4156                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4157                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
4158                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 3),
4159                ],
4160                cx,
4161            )
4162            .unwrap();
4163            view.paste(&Paste, cx);
4164            assert_eq!(
4165                view.display_text(cx),
4166                "123\n4567\n9\n( 8ne✅ three five ) two one✅ four three six five ( one✅ three five ) "
4167            );
4168            assert_eq!(
4169                view.selection_ranges(cx),
4170                &[
4171                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4172                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4173                    DisplayPoint::new(3, 3)..DisplayPoint::new(3, 3),
4174                ]
4175            );
4176        });
4177
4178        // Copy with a single cursor only, which writes the whole line into the clipboard.
4179        view.update(cx, |view, cx| {
4180            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)], cx)
4181                .unwrap();
4182            view.copy(&Copy, cx);
4183        });
4184
4185        // Paste with three selections, noticing how the copied full-line selection is inserted
4186        // before the empty selections but replaces the selection that is non-empty.
4187        view.update(cx, |view, cx| {
4188            view.select_display_ranges(
4189                &[
4190                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4191                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 2),
4192                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4193                ],
4194                cx,
4195            )
4196            .unwrap();
4197            view.paste(&Paste, cx);
4198            assert_eq!(
4199                view.display_text(cx),
4200                "123\n123\n123\n67\n123\n9\n( 8ne✅ three five ) two one✅ four three six five ( one✅ three five ) "
4201            );
4202            assert_eq!(
4203                view.selection_ranges(cx),
4204                &[
4205                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
4206                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
4207                    DisplayPoint::new(5, 1)..DisplayPoint::new(5, 1),
4208                ]
4209            );
4210        });
4211    }
4212
4213    #[gpui::test]
4214    fn test_select_all(cx: &mut gpui::MutableAppContext) {
4215        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\nde\nfgh", cx));
4216        let settings = EditorSettings::test(&cx);
4217        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
4218        view.update(cx, |view, cx| {
4219            view.select_all(&SelectAll, cx);
4220            assert_eq!(
4221                view.selection_ranges(cx),
4222                &[DisplayPoint::new(0, 0)..DisplayPoint::new(2, 3)]
4223            );
4224        });
4225    }
4226
4227    #[gpui::test]
4228    fn test_select_line(cx: &mut gpui::MutableAppContext) {
4229        let settings = EditorSettings::test(&cx);
4230        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 5), cx));
4231        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
4232        view.update(cx, |view, cx| {
4233            view.select_display_ranges(
4234                &[
4235                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
4236                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4237                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
4238                    DisplayPoint::new(4, 2)..DisplayPoint::new(4, 2),
4239                ],
4240                cx,
4241            )
4242            .unwrap();
4243            view.select_line(&SelectLine, cx);
4244            assert_eq!(
4245                view.selection_ranges(cx),
4246                vec![
4247                    DisplayPoint::new(0, 0)..DisplayPoint::new(2, 0),
4248                    DisplayPoint::new(4, 0)..DisplayPoint::new(5, 0),
4249                ]
4250            );
4251        });
4252
4253        view.update(cx, |view, cx| {
4254            view.select_line(&SelectLine, cx);
4255            assert_eq!(
4256                view.selection_ranges(cx),
4257                vec![
4258                    DisplayPoint::new(0, 0)..DisplayPoint::new(3, 0),
4259                    DisplayPoint::new(4, 0)..DisplayPoint::new(5, 5),
4260                ]
4261            );
4262        });
4263
4264        view.update(cx, |view, cx| {
4265            view.select_line(&SelectLine, cx);
4266            assert_eq!(
4267                view.selection_ranges(cx),
4268                vec![DisplayPoint::new(0, 0)..DisplayPoint::new(5, 5)]
4269            );
4270        });
4271    }
4272
4273    #[gpui::test]
4274    fn test_split_selection_into_lines(cx: &mut gpui::MutableAppContext) {
4275        let settings = EditorSettings::test(&cx);
4276        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(9, 5), cx));
4277        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
4278        view.update(cx, |view, cx| {
4279            view.fold_ranges(
4280                vec![
4281                    Point::new(0, 2)..Point::new(1, 2),
4282                    Point::new(2, 3)..Point::new(4, 1),
4283                    Point::new(7, 0)..Point::new(8, 4),
4284                ],
4285                cx,
4286            );
4287            view.select_display_ranges(
4288                &[
4289                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
4290                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4291                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
4292                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 4),
4293                ],
4294                cx,
4295            )
4296            .unwrap();
4297            assert_eq!(view.display_text(cx), "aa…bbb\nccc…eeee\nfffff\nggggg\n…i");
4298        });
4299
4300        view.update(cx, |view, cx| {
4301            view.split_selection_into_lines(&SplitSelectionIntoLines, cx);
4302            assert_eq!(
4303                view.display_text(cx),
4304                "aaaaa\nbbbbb\nccc…eeee\nfffff\nggggg\n…i"
4305            );
4306            assert_eq!(
4307                view.selection_ranges(cx),
4308                [
4309                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4310                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4311                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 0),
4312                    DisplayPoint::new(5, 4)..DisplayPoint::new(5, 4)
4313                ]
4314            );
4315        });
4316
4317        view.update(cx, |view, cx| {
4318            view.select_display_ranges(&[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 1)], cx)
4319                .unwrap();
4320            view.split_selection_into_lines(&SplitSelectionIntoLines, cx);
4321            assert_eq!(
4322                view.display_text(cx),
4323                "aaaaa\nbbbbb\nccccc\nddddd\neeeee\nfffff\nggggg\nhhhhh\niiiii"
4324            );
4325            assert_eq!(
4326                view.selection_ranges(cx),
4327                [
4328                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4329                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
4330                    DisplayPoint::new(2, 5)..DisplayPoint::new(2, 5),
4331                    DisplayPoint::new(3, 5)..DisplayPoint::new(3, 5),
4332                    DisplayPoint::new(4, 5)..DisplayPoint::new(4, 5),
4333                    DisplayPoint::new(5, 5)..DisplayPoint::new(5, 5),
4334                    DisplayPoint::new(6, 5)..DisplayPoint::new(6, 5),
4335                    DisplayPoint::new(7, 0)..DisplayPoint::new(7, 0)
4336                ]
4337            );
4338        });
4339    }
4340
4341    #[gpui::test]
4342    fn test_add_selection_above_below(cx: &mut gpui::MutableAppContext) {
4343        let settings = EditorSettings::test(&cx);
4344        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndefghi\n\njk\nlmno\n", cx));
4345        let (_, view) = cx.add_window(Default::default(), |cx| build_editor(buffer, settings, cx));
4346
4347        view.update(cx, |view, cx| {
4348            view.select_display_ranges(&[DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)], cx)
4349                .unwrap();
4350        });
4351        view.update(cx, |view, cx| {
4352            view.add_selection_above(&AddSelectionAbove, cx);
4353            assert_eq!(
4354                view.selection_ranges(cx),
4355                vec![
4356                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
4357                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)
4358                ]
4359            );
4360        });
4361
4362        view.update(cx, |view, cx| {
4363            view.add_selection_above(&AddSelectionAbove, cx);
4364            assert_eq!(
4365                view.selection_ranges(cx),
4366                vec![
4367                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
4368                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)
4369                ]
4370            );
4371        });
4372
4373        view.update(cx, |view, cx| {
4374            view.add_selection_below(&AddSelectionBelow, cx);
4375            assert_eq!(
4376                view.selection_ranges(cx),
4377                vec![DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)]
4378            );
4379        });
4380
4381        view.update(cx, |view, cx| {
4382            view.add_selection_below(&AddSelectionBelow, cx);
4383            assert_eq!(
4384                view.selection_ranges(cx),
4385                vec![
4386                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3),
4387                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 3)
4388                ]
4389            );
4390        });
4391
4392        view.update(cx, |view, cx| {
4393            view.add_selection_below(&AddSelectionBelow, cx);
4394            assert_eq!(
4395                view.selection_ranges(cx),
4396                vec![
4397                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3),
4398                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 3)
4399                ]
4400            );
4401        });
4402
4403        view.update(cx, |view, cx| {
4404            view.select_display_ranges(&[DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)], cx)
4405                .unwrap();
4406        });
4407        view.update(cx, |view, cx| {
4408            view.add_selection_below(&AddSelectionBelow, cx);
4409            assert_eq!(
4410                view.selection_ranges(cx),
4411                vec![
4412                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
4413                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 3)
4414                ]
4415            );
4416        });
4417
4418        view.update(cx, |view, cx| {
4419            view.add_selection_below(&AddSelectionBelow, cx);
4420            assert_eq!(
4421                view.selection_ranges(cx),
4422                vec![
4423                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
4424                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 3)
4425                ]
4426            );
4427        });
4428
4429        view.update(cx, |view, cx| {
4430            view.add_selection_above(&AddSelectionAbove, cx);
4431            assert_eq!(
4432                view.selection_ranges(cx),
4433                vec![DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)]
4434            );
4435        });
4436
4437        view.update(cx, |view, cx| {
4438            view.add_selection_above(&AddSelectionAbove, cx);
4439            assert_eq!(
4440                view.selection_ranges(cx),
4441                vec![DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)]
4442            );
4443        });
4444
4445        view.update(cx, |view, cx| {
4446            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(1, 4)], cx)
4447                .unwrap();
4448            view.add_selection_below(&AddSelectionBelow, cx);
4449            assert_eq!(
4450                view.selection_ranges(cx),
4451                vec![
4452                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4453                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4454                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4455                ]
4456            );
4457        });
4458
4459        view.update(cx, |view, cx| {
4460            view.add_selection_below(&AddSelectionBelow, cx);
4461            assert_eq!(
4462                view.selection_ranges(cx),
4463                vec![
4464                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4465                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4466                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4467                    DisplayPoint::new(4, 1)..DisplayPoint::new(4, 4),
4468                ]
4469            );
4470        });
4471
4472        view.update(cx, |view, cx| {
4473            view.add_selection_above(&AddSelectionAbove, cx);
4474            assert_eq!(
4475                view.selection_ranges(cx),
4476                vec![
4477                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4478                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4479                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4480                ]
4481            );
4482        });
4483
4484        view.update(cx, |view, cx| {
4485            view.select_display_ranges(&[DisplayPoint::new(4, 3)..DisplayPoint::new(1, 1)], cx)
4486                .unwrap();
4487        });
4488        view.update(cx, |view, cx| {
4489            view.add_selection_above(&AddSelectionAbove, cx);
4490            assert_eq!(
4491                view.selection_ranges(cx),
4492                vec![
4493                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 1),
4494                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 1),
4495                    DisplayPoint::new(3, 2)..DisplayPoint::new(3, 1),
4496                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 1),
4497                ]
4498            );
4499        });
4500
4501        view.update(cx, |view, cx| {
4502            view.add_selection_below(&AddSelectionBelow, cx);
4503            assert_eq!(
4504                view.selection_ranges(cx),
4505                vec![
4506                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 1),
4507                    DisplayPoint::new(3, 2)..DisplayPoint::new(3, 1),
4508                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 1),
4509                ]
4510            );
4511        });
4512    }
4513
4514    #[gpui::test]
4515    async fn test_select_larger_smaller_syntax_node(mut cx: gpui::TestAppContext) {
4516        let settings = cx.read(EditorSettings::test);
4517        let language = Some(Arc::new(Language::new(
4518            LanguageConfig::default(),
4519            tree_sitter_rust::language(),
4520        )));
4521
4522        let text = r#"
4523            use mod1::mod2::{mod3, mod4};
4524
4525            fn fn_1(param1: bool, param2: &str) {
4526                let var1 = "text";
4527            }
4528        "#
4529        .unindent();
4530
4531        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx).with_language(language, None, cx));
4532        let (_, view) = cx.add_window(|cx| build_editor(buffer, settings, cx));
4533        view.condition(&cx, |view, cx| !view.buffer.read(cx).is_parsing())
4534            .await;
4535
4536        view.update(&mut cx, |view, cx| {
4537            view.select_display_ranges(
4538                &[
4539                    DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4540                    DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4541                    DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4542                ],
4543                cx,
4544            )
4545            .unwrap();
4546            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4547        });
4548        assert_eq!(
4549            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4550            &[
4551                DisplayPoint::new(0, 23)..DisplayPoint::new(0, 27),
4552                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4553                DisplayPoint::new(3, 15)..DisplayPoint::new(3, 21),
4554            ]
4555        );
4556
4557        view.update(&mut cx, |view, cx| {
4558            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4559        });
4560        assert_eq!(
4561            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4562            &[
4563                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4564                DisplayPoint::new(4, 1)..DisplayPoint::new(2, 0),
4565            ]
4566        );
4567
4568        view.update(&mut cx, |view, cx| {
4569            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4570        });
4571        assert_eq!(
4572            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4573            &[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 0)]
4574        );
4575
4576        // Trying to expand the selected syntax node one more time has no effect.
4577        view.update(&mut cx, |view, cx| {
4578            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4579        });
4580        assert_eq!(
4581            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4582            &[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 0)]
4583        );
4584
4585        view.update(&mut cx, |view, cx| {
4586            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4587        });
4588        assert_eq!(
4589            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4590            &[
4591                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4592                DisplayPoint::new(4, 1)..DisplayPoint::new(2, 0),
4593            ]
4594        );
4595
4596        view.update(&mut cx, |view, cx| {
4597            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4598        });
4599        assert_eq!(
4600            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4601            &[
4602                DisplayPoint::new(0, 23)..DisplayPoint::new(0, 27),
4603                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4604                DisplayPoint::new(3, 15)..DisplayPoint::new(3, 21),
4605            ]
4606        );
4607
4608        view.update(&mut cx, |view, cx| {
4609            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4610        });
4611        assert_eq!(
4612            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4613            &[
4614                DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4615                DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4616                DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4617            ]
4618        );
4619
4620        // Trying to shrink the selected syntax node one more time has no effect.
4621        view.update(&mut cx, |view, cx| {
4622            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4623        });
4624        assert_eq!(
4625            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4626            &[
4627                DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4628                DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4629                DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4630            ]
4631        );
4632
4633        // Ensure that we keep expanding the selection if the larger selection starts or ends within
4634        // a fold.
4635        view.update(&mut cx, |view, cx| {
4636            view.fold_ranges(
4637                vec![
4638                    Point::new(0, 21)..Point::new(0, 24),
4639                    Point::new(3, 20)..Point::new(3, 22),
4640                ],
4641                cx,
4642            );
4643            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4644        });
4645        assert_eq!(
4646            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4647            &[
4648                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4649                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4650                DisplayPoint::new(3, 4)..DisplayPoint::new(3, 23),
4651            ]
4652        );
4653    }
4654
4655    #[gpui::test]
4656    async fn test_autoclose_pairs(mut cx: gpui::TestAppContext) {
4657        let settings = cx.read(EditorSettings::test);
4658        let language = Some(Arc::new(Language::new(
4659            LanguageConfig {
4660                brackets: vec![
4661                    BracketPair {
4662                        start: "{".to_string(),
4663                        end: "}".to_string(),
4664                        close: true,
4665                        newline: true,
4666                    },
4667                    BracketPair {
4668                        start: "/*".to_string(),
4669                        end: " */".to_string(),
4670                        close: true,
4671                        newline: true,
4672                    },
4673                ],
4674                ..Default::default()
4675            },
4676            tree_sitter_rust::language(),
4677        )));
4678
4679        let text = r#"
4680            a
4681
4682            /
4683
4684        "#
4685        .unindent();
4686
4687        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx).with_language(language, None, cx));
4688        let (_, view) = cx.add_window(|cx| build_editor(buffer, settings, cx));
4689        view.condition(&cx, |view, cx| !view.buffer.read(cx).is_parsing())
4690            .await;
4691
4692        view.update(&mut cx, |view, cx| {
4693            view.select_display_ranges(
4694                &[
4695                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
4696                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
4697                ],
4698                cx,
4699            )
4700            .unwrap();
4701            view.handle_input(&Input("{".to_string()), cx);
4702            view.handle_input(&Input("{".to_string()), cx);
4703            view.handle_input(&Input("{".to_string()), cx);
4704            assert_eq!(
4705                view.text(cx),
4706                "
4707                {{{}}}
4708                {{{}}}
4709                /
4710
4711                "
4712                .unindent()
4713            );
4714
4715            view.move_right(&MoveRight, cx);
4716            view.handle_input(&Input("}".to_string()), cx);
4717            view.handle_input(&Input("}".to_string()), cx);
4718            view.handle_input(&Input("}".to_string()), cx);
4719            assert_eq!(
4720                view.text(cx),
4721                "
4722                {{{}}}}
4723                {{{}}}}
4724                /
4725
4726                "
4727                .unindent()
4728            );
4729
4730            view.undo(&Undo, cx);
4731            view.handle_input(&Input("/".to_string()), cx);
4732            view.handle_input(&Input("*".to_string()), cx);
4733            assert_eq!(
4734                view.text(cx),
4735                "
4736                /* */
4737                /* */
4738                /
4739
4740                "
4741                .unindent()
4742            );
4743
4744            view.undo(&Undo, cx);
4745            view.select_display_ranges(
4746                &[
4747                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
4748                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
4749                ],
4750                cx,
4751            )
4752            .unwrap();
4753            view.handle_input(&Input("*".to_string()), cx);
4754            assert_eq!(
4755                view.text(cx),
4756                "
4757                a
4758
4759                /*
4760                *
4761                "
4762                .unindent()
4763            );
4764        });
4765    }
4766
4767    #[gpui::test]
4768    async fn test_extra_newline_insertion(mut cx: gpui::TestAppContext) {
4769        let settings = cx.read(EditorSettings::test);
4770        let language = Some(Arc::new(Language::new(
4771            LanguageConfig {
4772                brackets: vec![
4773                    BracketPair {
4774                        start: "{".to_string(),
4775                        end: "}".to_string(),
4776                        close: true,
4777                        newline: true,
4778                    },
4779                    BracketPair {
4780                        start: "/* ".to_string(),
4781                        end: " */".to_string(),
4782                        close: true,
4783                        newline: true,
4784                    },
4785                ],
4786                ..Default::default()
4787            },
4788            tree_sitter_rust::language(),
4789        )));
4790
4791        let text = concat!(
4792            "{   }\n",     // Suppress rustfmt
4793            "  x\n",       //
4794            "  /*   */\n", //
4795            "x\n",         //
4796            "{{} }\n",     //
4797        );
4798
4799        let buffer = cx.add_model(|cx| Buffer::new(0, text, cx).with_language(language, None, cx));
4800        let (_, view) = cx.add_window(|cx| build_editor(buffer, settings, cx));
4801        view.condition(&cx, |view, cx| !view.buffer.read(cx).is_parsing())
4802            .await;
4803
4804        view.update(&mut cx, |view, cx| {
4805            view.select_display_ranges(
4806                &[
4807                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 3),
4808                    DisplayPoint::new(2, 5)..DisplayPoint::new(2, 5),
4809                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 4),
4810                ],
4811                cx,
4812            )
4813            .unwrap();
4814            view.newline(&Newline, cx);
4815
4816            assert_eq!(
4817                view.buffer().read(cx).text(),
4818                concat!(
4819                    "{ \n",    // Suppress rustfmt
4820                    "\n",      //
4821                    "}\n",     //
4822                    "  x\n",   //
4823                    "  /* \n", //
4824                    "  \n",    //
4825                    "  */\n",  //
4826                    "x\n",     //
4827                    "{{} \n",  //
4828                    "}\n",     //
4829                )
4830            );
4831        });
4832    }
4833
4834    impl Editor {
4835        fn selection_ranges(&self, cx: &mut MutableAppContext) -> Vec<Range<DisplayPoint>> {
4836            self.selections_in_range(
4837                self.selection_set_id,
4838                DisplayPoint::zero()..self.max_point(cx),
4839                cx,
4840            )
4841            .collect::<Vec<_>>()
4842        }
4843    }
4844
4845    fn empty_range(row: usize, column: usize) -> Range<DisplayPoint> {
4846        let point = DisplayPoint::new(row as u32, column as u32);
4847        point..point
4848    }
4849
4850    fn build_editor(
4851        buffer: ModelHandle<Buffer>,
4852        settings: EditorSettings,
4853        cx: &mut ViewContext<Editor>,
4854    ) -> Editor {
4855        Editor::for_buffer(buffer, move |_| settings.clone(), cx)
4856    }
4857}
4858
4859trait RangeExt<T> {
4860    fn sorted(&self) -> Range<T>;
4861    fn to_inclusive(&self) -> RangeInclusive<T>;
4862}
4863
4864impl<T: Ord + Clone> RangeExt<T> for Range<T> {
4865    fn sorted(&self) -> Self {
4866        cmp::min(&self.start, &self.end).clone()..cmp::max(&self.start, &self.end).clone()
4867    }
4868
4869    fn to_inclusive(&self) -> RangeInclusive<T> {
4870        self.start.clone()..=self.end.clone()
4871    }
4872}