lib.rs

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