editor.rs

   1pub mod buffer;
   2pub mod display_map;
   3mod element;
   4pub mod movement;
   5
   6use crate::{
   7    settings::{HighlightId, Settings},
   8    theme::{EditorStyle, Theme},
   9    time::ReplicaId,
  10    util::{post_inc, Bias},
  11    workspace,
  12    worktree::{File, Worktree},
  13};
  14use anyhow::Result;
  15pub use buffer::*;
  16pub use display_map::DisplayPoint;
  17use display_map::*;
  18pub use element::*;
  19use gpui::{
  20    action, color::Color, font_cache::FamilyId, fonts::Properties as FontProperties,
  21    geometry::vector::Vector2F, keymap::Binding, text_layout, AppContext, ClipboardItem, Element,
  22    ElementBox, Entity, FontCache, ModelHandle, MutableAppContext, RenderContext, Task,
  23    TextLayoutCache, View, ViewContext, WeakViewHandle,
  24};
  25use postage::watch;
  26use serde::{Deserialize, Serialize};
  27use smallvec::SmallVec;
  28use smol::Timer;
  29use std::{
  30    cell::RefCell,
  31    cmp::{self, Ordering},
  32    collections::BTreeMap,
  33    fmt::Write,
  34    iter::FromIterator,
  35    mem,
  36    ops::{Range, RangeInclusive},
  37    path::Path,
  38    rc::Rc,
  39    sync::Arc,
  40    time::Duration,
  41};
  42
  43const CURSOR_BLINK_INTERVAL: Duration = Duration::from_millis(500);
  44const MAX_LINE_LEN: usize = 1024;
  45
  46action!(Cancel);
  47action!(Backspace);
  48action!(Delete);
  49action!(Newline, bool);
  50action!(Insert, String);
  51action!(DeleteLine);
  52action!(DeleteToPreviousWordBoundary);
  53action!(DeleteToNextWordBoundary);
  54action!(DeleteToBeginningOfLine);
  55action!(DeleteToEndOfLine);
  56action!(CutToEndOfLine);
  57action!(DuplicateLine);
  58action!(MoveLineUp);
  59action!(MoveLineDown);
  60action!(Cut);
  61action!(Copy);
  62action!(Paste);
  63action!(Undo);
  64action!(Redo);
  65action!(MoveUp);
  66action!(MoveDown);
  67action!(MoveLeft);
  68action!(MoveRight);
  69action!(MoveToPreviousWordBoundary);
  70action!(MoveToNextWordBoundary);
  71action!(MoveToBeginningOfLine);
  72action!(MoveToEndOfLine);
  73action!(MoveToBeginning);
  74action!(MoveToEnd);
  75action!(SelectUp);
  76action!(SelectDown);
  77action!(SelectLeft);
  78action!(SelectRight);
  79action!(SelectToPreviousWordBoundary);
  80action!(SelectToNextWordBoundary);
  81action!(SelectToBeginningOfLine, bool);
  82action!(SelectToEndOfLine);
  83action!(SelectToBeginning);
  84action!(SelectToEnd);
  85action!(SelectAll);
  86action!(SelectLine);
  87action!(SplitSelectionIntoLines);
  88action!(AddSelectionAbove);
  89action!(AddSelectionBelow);
  90action!(SelectLargerSyntaxNode);
  91action!(SelectSmallerSyntaxNode);
  92action!(MoveToEnclosingBracket);
  93action!(PageUp);
  94action!(PageDown);
  95action!(Fold);
  96action!(Unfold);
  97action!(FoldSelectedRanges);
  98action!(Scroll, Vector2F);
  99action!(Select, SelectPhase);
 100
 101pub fn init(cx: &mut MutableAppContext) {
 102    cx.add_bindings(vec![
 103        Binding::new("escape", Cancel, Some("BufferView")),
 104        Binding::new("backspace", Backspace, Some("BufferView")),
 105        Binding::new("ctrl-h", Backspace, Some("BufferView")),
 106        Binding::new("delete", Delete, Some("BufferView")),
 107        Binding::new("ctrl-d", Delete, Some("BufferView")),
 108        Binding::new("enter", Newline(false), Some("BufferView")),
 109        Binding::new("alt-enter", Newline(true), Some("BufferView")),
 110        Binding::new("tab", Insert("\t".into()), Some("BufferView")),
 111        Binding::new("ctrl-shift-K", DeleteLine, Some("BufferView")),
 112        Binding::new(
 113            "alt-backspace",
 114            DeleteToPreviousWordBoundary,
 115            Some("BufferView"),
 116        ),
 117        Binding::new("alt-h", DeleteToPreviousWordBoundary, Some("BufferView")),
 118        Binding::new("alt-delete", DeleteToNextWordBoundary, Some("BufferView")),
 119        Binding::new("alt-d", DeleteToNextWordBoundary, Some("BufferView")),
 120        Binding::new("cmd-backspace", DeleteToBeginningOfLine, Some("BufferView")),
 121        Binding::new("cmd-delete", DeleteToEndOfLine, Some("BufferView")),
 122        Binding::new("ctrl-k", CutToEndOfLine, Some("BufferView")),
 123        Binding::new("cmd-shift-D", DuplicateLine, Some("BufferView")),
 124        Binding::new("ctrl-cmd-up", MoveLineUp, Some("BufferView")),
 125        Binding::new("ctrl-cmd-down", MoveLineDown, Some("BufferView")),
 126        Binding::new("cmd-x", Cut, Some("BufferView")),
 127        Binding::new("cmd-c", Copy, Some("BufferView")),
 128        Binding::new("cmd-v", Paste, Some("BufferView")),
 129        Binding::new("cmd-z", Undo, Some("BufferView")),
 130        Binding::new("cmd-shift-Z", Redo, Some("BufferView")),
 131        Binding::new("up", MoveUp, Some("BufferView")),
 132        Binding::new("down", MoveDown, Some("BufferView")),
 133        Binding::new("left", MoveLeft, Some("BufferView")),
 134        Binding::new("right", MoveRight, Some("BufferView")),
 135        Binding::new("ctrl-p", MoveUp, Some("BufferView")),
 136        Binding::new("ctrl-n", MoveDown, Some("BufferView")),
 137        Binding::new("ctrl-b", MoveLeft, Some("BufferView")),
 138        Binding::new("ctrl-f", MoveRight, Some("BufferView")),
 139        Binding::new("alt-left", MoveToPreviousWordBoundary, Some("BufferView")),
 140        Binding::new("alt-b", MoveToPreviousWordBoundary, Some("BufferView")),
 141        Binding::new("alt-right", MoveToNextWordBoundary, Some("BufferView")),
 142        Binding::new("alt-f", MoveToNextWordBoundary, Some("BufferView")),
 143        Binding::new("cmd-left", MoveToBeginningOfLine, Some("BufferView")),
 144        Binding::new("ctrl-a", MoveToBeginningOfLine, Some("BufferView")),
 145        Binding::new("cmd-right", MoveToEndOfLine, Some("BufferView")),
 146        Binding::new("ctrl-e", MoveToEndOfLine, Some("BufferView")),
 147        Binding::new("cmd-up", MoveToBeginning, Some("BufferView")),
 148        Binding::new("cmd-down", MoveToEnd, Some("BufferView")),
 149        Binding::new("shift-up", SelectUp, Some("BufferView")),
 150        Binding::new("ctrl-shift-P", SelectUp, Some("BufferView")),
 151        Binding::new("shift-down", SelectDown, Some("BufferView")),
 152        Binding::new("ctrl-shift-N", SelectDown, Some("BufferView")),
 153        Binding::new("shift-left", SelectLeft, Some("BufferView")),
 154        Binding::new("ctrl-shift-B", SelectLeft, Some("BufferView")),
 155        Binding::new("shift-right", SelectRight, Some("BufferView")),
 156        Binding::new("ctrl-shift-F", SelectRight, Some("BufferView")),
 157        Binding::new(
 158            "alt-shift-left",
 159            SelectToPreviousWordBoundary,
 160            Some("BufferView"),
 161        ),
 162        Binding::new(
 163            "alt-shift-B",
 164            SelectToPreviousWordBoundary,
 165            Some("BufferView"),
 166        ),
 167        Binding::new(
 168            "alt-shift-right",
 169            SelectToNextWordBoundary,
 170            Some("BufferView"),
 171        ),
 172        Binding::new("alt-shift-F", SelectToNextWordBoundary, Some("BufferView")),
 173        Binding::new(
 174            "cmd-shift-left",
 175            SelectToBeginningOfLine(true),
 176            Some("BufferView"),
 177        ),
 178        Binding::new(
 179            "ctrl-shift-A",
 180            SelectToBeginningOfLine(true),
 181            Some("BufferView"),
 182        ),
 183        Binding::new("cmd-shift-right", SelectToEndOfLine, Some("BufferView")),
 184        Binding::new("ctrl-shift-E", SelectToEndOfLine, Some("BufferView")),
 185        Binding::new("cmd-shift-up", SelectToBeginning, Some("BufferView")),
 186        Binding::new("cmd-shift-down", SelectToEnd, Some("BufferView")),
 187        Binding::new("cmd-a", SelectAll, Some("BufferView")),
 188        Binding::new("cmd-l", SelectLine, Some("BufferView")),
 189        Binding::new("cmd-shift-L", SplitSelectionIntoLines, Some("BufferView")),
 190        Binding::new("cmd-alt-up", AddSelectionAbove, Some("BufferView")),
 191        Binding::new("cmd-ctrl-p", AddSelectionAbove, Some("BufferView")),
 192        Binding::new("cmd-alt-down", AddSelectionBelow, Some("BufferView")),
 193        Binding::new("cmd-ctrl-n", AddSelectionBelow, Some("BufferView")),
 194        Binding::new("alt-up", SelectLargerSyntaxNode, Some("BufferView")),
 195        Binding::new("ctrl-w", SelectLargerSyntaxNode, Some("BufferView")),
 196        Binding::new("alt-down", SelectSmallerSyntaxNode, Some("BufferView")),
 197        Binding::new("ctrl-shift-W", SelectSmallerSyntaxNode, Some("BufferView")),
 198        Binding::new("ctrl-m", MoveToEnclosingBracket, Some("BufferView")),
 199        Binding::new("pageup", PageUp, Some("BufferView")),
 200        Binding::new("pagedown", PageDown, Some("BufferView")),
 201        Binding::new("alt-cmd-[", Fold, Some("BufferView")),
 202        Binding::new("alt-cmd-]", Unfold, Some("BufferView")),
 203        Binding::new("alt-cmd-f", FoldSelectedRanges, Some("BufferView")),
 204    ]);
 205
 206    cx.add_action(|this: &mut Editor, action: &Scroll, cx| this.set_scroll_position(action.0, cx));
 207    cx.add_action(Editor::select);
 208    cx.add_action(Editor::cancel);
 209    cx.add_action(Editor::insert);
 210    cx.add_action(Editor::newline);
 211    cx.add_action(Editor::backspace);
 212    cx.add_action(Editor::delete);
 213    cx.add_action(Editor::delete_line);
 214    cx.add_action(Editor::delete_to_previous_word_boundary);
 215    cx.add_action(Editor::delete_to_next_word_boundary);
 216    cx.add_action(Editor::delete_to_beginning_of_line);
 217    cx.add_action(Editor::delete_to_end_of_line);
 218    cx.add_action(Editor::cut_to_end_of_line);
 219    cx.add_action(Editor::duplicate_line);
 220    cx.add_action(Editor::move_line_up);
 221    cx.add_action(Editor::move_line_down);
 222    cx.add_action(Editor::cut);
 223    cx.add_action(Editor::copy);
 224    cx.add_action(Editor::paste);
 225    cx.add_action(Editor::undo);
 226    cx.add_action(Editor::redo);
 227    cx.add_action(Editor::move_up);
 228    cx.add_action(Editor::move_down);
 229    cx.add_action(Editor::move_left);
 230    cx.add_action(Editor::move_right);
 231    cx.add_action(Editor::move_to_previous_word_boundary);
 232    cx.add_action(Editor::move_to_next_word_boundary);
 233    cx.add_action(Editor::move_to_beginning_of_line);
 234    cx.add_action(Editor::move_to_end_of_line);
 235    cx.add_action(Editor::move_to_beginning);
 236    cx.add_action(Editor::move_to_end);
 237    cx.add_action(Editor::select_up);
 238    cx.add_action(Editor::select_down);
 239    cx.add_action(Editor::select_left);
 240    cx.add_action(Editor::select_right);
 241    cx.add_action(Editor::select_to_previous_word_boundary);
 242    cx.add_action(Editor::select_to_next_word_boundary);
 243    cx.add_action(Editor::select_to_beginning_of_line);
 244    cx.add_action(Editor::select_to_end_of_line);
 245    cx.add_action(Editor::select_to_beginning);
 246    cx.add_action(Editor::select_to_end);
 247    cx.add_action(Editor::select_all);
 248    cx.add_action(Editor::select_line);
 249    cx.add_action(Editor::split_selection_into_lines);
 250    cx.add_action(Editor::add_selection_above);
 251    cx.add_action(Editor::add_selection_below);
 252    cx.add_action(Editor::select_larger_syntax_node);
 253    cx.add_action(Editor::select_smaller_syntax_node);
 254    cx.add_action(Editor::move_to_enclosing_bracket);
 255    cx.add_action(Editor::page_up);
 256    cx.add_action(Editor::page_down);
 257    cx.add_action(Editor::fold);
 258    cx.add_action(Editor::unfold);
 259    cx.add_action(Editor::fold_selected_ranges);
 260}
 261
 262#[derive(Clone, Debug)]
 263pub enum SelectPhase {
 264    Begin {
 265        position: DisplayPoint,
 266        add: bool,
 267    },
 268    Update {
 269        position: DisplayPoint,
 270        scroll_position: Vector2F,
 271    },
 272    End,
 273}
 274
 275enum EditorMode {
 276    SingleLine,
 277    AutoHeight,
 278    Full,
 279}
 280
 281pub struct Editor {
 282    handle: WeakViewHandle<Self>,
 283    buffer: ModelHandle<Buffer>,
 284    display_map: ModelHandle<DisplayMap>,
 285    selection_set_id: SelectionSetId,
 286    pending_selection: Option<Selection>,
 287    next_selection_id: usize,
 288    add_selections_state: Option<AddSelectionsState>,
 289    select_larger_syntax_node_stack: Vec<Vec<Selection>>,
 290    scroll_position: Vector2F,
 291    scroll_top_anchor: Anchor,
 292    autoscroll_requested: bool,
 293    build_style: Option<Rc<RefCell<dyn FnMut(&mut MutableAppContext) -> EditorStyle>>>,
 294    settings: watch::Receiver<Settings>,
 295    focused: bool,
 296    cursors_visible: bool,
 297    blink_epoch: usize,
 298    blinking_paused: bool,
 299    mode: EditorMode,
 300    placeholder_text: Option<Arc<str>>,
 301}
 302
 303pub struct Snapshot {
 304    pub display_snapshot: DisplayMapSnapshot,
 305    pub placeholder_text: Option<Arc<str>>,
 306    pub gutter_visible: bool,
 307    pub auto_height: bool,
 308    pub theme: Arc<Theme>,
 309    pub font_family: FamilyId,
 310    pub font_size: f32,
 311    is_focused: bool,
 312    scroll_position: Vector2F,
 313    scroll_top_anchor: Anchor,
 314}
 315
 316struct AddSelectionsState {
 317    above: bool,
 318    stack: Vec<usize>,
 319}
 320
 321#[derive(Serialize, Deserialize)]
 322struct ClipboardSelection {
 323    len: usize,
 324    is_entire_line: bool,
 325}
 326
 327impl Editor {
 328    pub fn single_line(settings: watch::Receiver<Settings>, cx: &mut ViewContext<Self>) -> Self {
 329        let buffer = cx.add_model(|cx| Buffer::new(0, String::new(), cx));
 330        let mut view = Self::for_buffer(buffer, settings, cx);
 331        view.mode = EditorMode::SingleLine;
 332        view
 333    }
 334
 335    pub fn auto_height(settings: watch::Receiver<Settings>, cx: &mut ViewContext<Self>) -> Self {
 336        let buffer = cx.add_model(|cx| Buffer::new(0, String::new(), cx));
 337        let mut view = Self::for_buffer(buffer, settings, cx);
 338        view.mode = EditorMode::AutoHeight;
 339        view
 340    }
 341
 342    pub fn for_buffer(
 343        buffer: ModelHandle<Buffer>,
 344        settings: watch::Receiver<Settings>,
 345        cx: &mut ViewContext<Self>,
 346    ) -> Self {
 347        let display_map =
 348            cx.add_model(|cx| DisplayMap::new(buffer.clone(), settings.borrow().clone(), None, cx));
 349        cx.observe(&buffer, Self::on_buffer_changed).detach();
 350        cx.subscribe(&buffer, Self::on_buffer_event).detach();
 351        cx.observe(&display_map, Self::on_display_map_changed)
 352            .detach();
 353
 354        let mut next_selection_id = 0;
 355        let selection_set_id = buffer.update(cx, |buffer, cx| {
 356            buffer.add_selection_set(
 357                vec![Selection {
 358                    id: post_inc(&mut next_selection_id),
 359                    start: buffer.anchor_before(0),
 360                    end: buffer.anchor_before(0),
 361                    reversed: false,
 362                    goal: SelectionGoal::None,
 363                }],
 364                cx,
 365            )
 366        });
 367        Self {
 368            handle: cx.handle().downgrade(),
 369            buffer,
 370            display_map,
 371            selection_set_id,
 372            pending_selection: None,
 373            next_selection_id,
 374            add_selections_state: None,
 375            select_larger_syntax_node_stack: Vec::new(),
 376            build_style: None,
 377            scroll_position: Vector2F::zero(),
 378            scroll_top_anchor: Anchor::min(),
 379            autoscroll_requested: false,
 380            settings,
 381            focused: false,
 382            cursors_visible: false,
 383            blink_epoch: 0,
 384            blinking_paused: false,
 385            mode: EditorMode::Full,
 386            placeholder_text: None,
 387        }
 388    }
 389
 390    pub fn with_style(
 391        mut self,
 392        f: impl 'static + FnMut(&mut MutableAppContext) -> EditorStyle,
 393    ) -> Self {
 394        self.build_style = Some(Rc::new(RefCell::new(f)));
 395        self
 396    }
 397
 398    pub fn replica_id(&self, cx: &AppContext) -> ReplicaId {
 399        self.buffer.read(cx).replica_id()
 400    }
 401
 402    pub fn buffer(&self) -> &ModelHandle<Buffer> {
 403        &self.buffer
 404    }
 405
 406    pub fn snapshot(&mut self, cx: &mut MutableAppContext) -> Snapshot {
 407        let settings = self.settings.borrow();
 408
 409        Snapshot {
 410            display_snapshot: self.display_map.update(cx, |map, cx| map.snapshot(cx)),
 411            gutter_visible: matches!(self.mode, EditorMode::Full),
 412            auto_height: matches!(self.mode, EditorMode::AutoHeight),
 413            scroll_position: self.scroll_position,
 414            scroll_top_anchor: self.scroll_top_anchor.clone(),
 415            theme: settings.theme.clone(),
 416            placeholder_text: self.placeholder_text.clone(),
 417            font_family: settings.buffer_font_family,
 418            font_size: settings.buffer_font_size,
 419            is_focused: self
 420                .handle
 421                .upgrade(cx)
 422                .map_or(false, |handle| handle.is_focused(cx)),
 423        }
 424    }
 425
 426    pub fn set_placeholder_text(
 427        &mut self,
 428        placeholder_text: impl Into<Arc<str>>,
 429        cx: &mut ViewContext<Self>,
 430    ) {
 431        self.placeholder_text = Some(placeholder_text.into());
 432        cx.notify();
 433    }
 434
 435    fn set_scroll_position(&mut self, mut scroll_position: Vector2F, cx: &mut ViewContext<Self>) {
 436        let map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 437        let scroll_top_buffer_offset =
 438            DisplayPoint::new(scroll_position.y() as u32, 0).to_buffer_offset(&map, Bias::Right);
 439        self.scroll_top_anchor = self
 440            .buffer
 441            .read(cx)
 442            .anchor_at(scroll_top_buffer_offset, Bias::Right);
 443        scroll_position.set_y(scroll_position.y().fract());
 444        self.scroll_position = scroll_position;
 445        cx.notify();
 446    }
 447
 448    pub fn clamp_scroll_left(&mut self, max: f32) -> bool {
 449        if max < self.scroll_position.x() {
 450            self.scroll_position.set_x(max);
 451            true
 452        } else {
 453            false
 454        }
 455    }
 456
 457    pub fn autoscroll_vertically(
 458        &mut self,
 459        viewport_height: f32,
 460        line_height: f32,
 461        cx: &mut ViewContext<Self>,
 462    ) -> bool {
 463        let visible_lines = viewport_height / line_height;
 464        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 465        let mut scroll_position =
 466            compute_scroll_position(&display_map, self.scroll_position, &self.scroll_top_anchor);
 467        let max_scroll_top = if matches!(self.mode, EditorMode::AutoHeight) {
 468            (display_map.max_point().row() as f32 - visible_lines + 1.).max(0.)
 469        } else {
 470            display_map.max_point().row().saturating_sub(1) as f32
 471        };
 472        if scroll_position.y() > max_scroll_top {
 473            scroll_position.set_y(max_scroll_top);
 474            self.set_scroll_position(scroll_position, cx);
 475        }
 476
 477        if self.autoscroll_requested {
 478            self.autoscroll_requested = false;
 479        } else {
 480            return false;
 481        }
 482
 483        let first_cursor_top = self
 484            .selections(cx)
 485            .first()
 486            .unwrap()
 487            .head()
 488            .to_display_point(&display_map, Bias::Left)
 489            .row() as f32;
 490        let last_cursor_bottom = self
 491            .selections(cx)
 492            .last()
 493            .unwrap()
 494            .head()
 495            .to_display_point(&display_map, Bias::Right)
 496            .row() as f32
 497            + 1.0;
 498
 499        let margin = if matches!(self.mode, EditorMode::AutoHeight) {
 500            0.
 501        } else {
 502            ((visible_lines - (last_cursor_bottom - first_cursor_top)) / 2.0)
 503                .floor()
 504                .min(3.0)
 505        };
 506        if margin < 0.0 {
 507            return false;
 508        }
 509
 510        let target_top = (first_cursor_top - margin).max(0.0);
 511        let target_bottom = last_cursor_bottom + margin;
 512        let start_row = scroll_position.y();
 513        let end_row = start_row + visible_lines;
 514
 515        if target_top < start_row {
 516            scroll_position.set_y(target_top);
 517            self.set_scroll_position(scroll_position, cx);
 518        } else if target_bottom >= end_row {
 519            scroll_position.set_y(target_bottom - visible_lines);
 520            self.set_scroll_position(scroll_position, cx);
 521        }
 522
 523        true
 524    }
 525
 526    pub fn autoscroll_horizontally(
 527        &mut self,
 528        start_row: u32,
 529        viewport_width: f32,
 530        scroll_width: f32,
 531        max_glyph_width: f32,
 532        layouts: &[text_layout::Line],
 533        cx: &mut MutableAppContext,
 534    ) -> bool {
 535        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 536        let mut target_left = std::f32::INFINITY;
 537        let mut target_right = 0.0_f32;
 538        for selection in self.selections(cx) {
 539            let head = selection.head().to_display_point(&display_map, Bias::Left);
 540            let start_column = head.column().saturating_sub(3);
 541            let end_column = cmp::min(display_map.line_len(head.row()), head.column() + 3);
 542            target_left = target_left
 543                .min(layouts[(head.row() - start_row) as usize].x_for_index(start_column as usize));
 544            target_right = target_right.max(
 545                layouts[(head.row() - start_row) as usize].x_for_index(end_column as usize)
 546                    + max_glyph_width,
 547            );
 548        }
 549        target_right = target_right.min(scroll_width);
 550
 551        if target_right - target_left > viewport_width {
 552            return false;
 553        }
 554
 555        let scroll_left = self.scroll_position.x() * max_glyph_width;
 556        let scroll_right = scroll_left + viewport_width;
 557
 558        if target_left < scroll_left {
 559            self.scroll_position.set_x(target_left / max_glyph_width);
 560            true
 561        } else if target_right > scroll_right {
 562            self.scroll_position
 563                .set_x((target_right - viewport_width) / max_glyph_width);
 564            true
 565        } else {
 566            false
 567        }
 568    }
 569
 570    fn select(&mut self, Select(phase): &Select, cx: &mut ViewContext<Self>) {
 571        match phase {
 572            SelectPhase::Begin { position, add } => self.begin_selection(*position, *add, cx),
 573            SelectPhase::Update {
 574                position,
 575                scroll_position,
 576            } => self.update_selection(*position, *scroll_position, cx),
 577            SelectPhase::End => self.end_selection(cx),
 578        }
 579    }
 580
 581    fn begin_selection(&mut self, position: DisplayPoint, add: bool, cx: &mut ViewContext<Self>) {
 582        if !self.focused {
 583            cx.focus_self();
 584            cx.emit(Event::Activate);
 585        }
 586
 587        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 588        let cursor = display_map.anchor_before(position, Bias::Left);
 589        let selection = Selection {
 590            id: post_inc(&mut self.next_selection_id),
 591            start: cursor.clone(),
 592            end: cursor,
 593            reversed: false,
 594            goal: SelectionGoal::None,
 595        };
 596
 597        if !add {
 598            self.update_selections(Vec::new(), false, cx);
 599        }
 600        self.pending_selection = Some(selection);
 601
 602        cx.notify();
 603    }
 604
 605    fn update_selection(
 606        &mut self,
 607        position: DisplayPoint,
 608        scroll_position: Vector2F,
 609        cx: &mut ViewContext<Self>,
 610    ) {
 611        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 612        let buffer = self.buffer.read(cx);
 613        let cursor = display_map.anchor_before(position, Bias::Left);
 614        if let Some(selection) = self.pending_selection.as_mut() {
 615            selection.set_head(buffer, cursor);
 616        } else {
 617            log::error!("update_selection dispatched with no pending selection");
 618            return;
 619        }
 620
 621        self.set_scroll_position(scroll_position, cx);
 622        cx.notify();
 623    }
 624
 625    fn end_selection(&mut self, cx: &mut ViewContext<Self>) {
 626        if let Some(selection) = self.pending_selection.take() {
 627            let mut selections = self.selections(cx.as_ref()).to_vec();
 628            let ix = self.selection_insertion_index(&selections, &selection.start, cx.as_ref());
 629            selections.insert(ix, selection);
 630            self.update_selections(selections, false, cx);
 631        } else {
 632            log::error!("end_selection dispatched with no pending selection");
 633        }
 634    }
 635
 636    pub fn is_selecting(&self) -> bool {
 637        self.pending_selection.is_some()
 638    }
 639
 640    pub fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
 641        let selections = self.selections(cx.as_ref());
 642        if let Some(pending_selection) = self.pending_selection.take() {
 643            if selections.is_empty() {
 644                self.update_selections(vec![pending_selection], true, cx);
 645            }
 646        } else {
 647            let mut oldest_selection = selections.iter().min_by_key(|s| s.id).unwrap().clone();
 648            if selections.len() == 1 {
 649                oldest_selection.start = oldest_selection.head().clone();
 650                oldest_selection.end = oldest_selection.head().clone();
 651            }
 652            self.update_selections(vec![oldest_selection], true, cx);
 653        }
 654    }
 655
 656    fn select_ranges<I, T>(&mut self, ranges: I, autoscroll: bool, cx: &mut ViewContext<Self>)
 657    where
 658        I: IntoIterator<Item = Range<T>>,
 659        T: ToOffset,
 660    {
 661        let buffer = self.buffer.read(cx);
 662        let mut selections = Vec::new();
 663        for range in ranges {
 664            let mut start = range.start.to_offset(buffer);
 665            let mut end = range.end.to_offset(buffer);
 666            let reversed = if start > end {
 667                mem::swap(&mut start, &mut end);
 668                true
 669            } else {
 670                false
 671            };
 672            selections.push(Selection {
 673                id: post_inc(&mut self.next_selection_id),
 674                start: buffer.anchor_before(start),
 675                end: buffer.anchor_before(end),
 676                reversed,
 677                goal: SelectionGoal::None,
 678            });
 679        }
 680        self.update_selections(selections, autoscroll, cx);
 681    }
 682
 683    #[cfg(test)]
 684    fn select_display_ranges<'a, T>(&mut self, ranges: T, cx: &mut ViewContext<Self>) -> Result<()>
 685    where
 686        T: IntoIterator<Item = &'a Range<DisplayPoint>>,
 687    {
 688        let mut selections = Vec::new();
 689        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 690        for range in ranges {
 691            let mut start = range.start;
 692            let mut end = range.end;
 693            let reversed = if start > end {
 694                mem::swap(&mut start, &mut end);
 695                true
 696            } else {
 697                false
 698            };
 699
 700            selections.push(Selection {
 701                id: post_inc(&mut self.next_selection_id),
 702                start: display_map.anchor_before(start, Bias::Left),
 703                end: display_map.anchor_before(end, Bias::Left),
 704                reversed,
 705                goal: SelectionGoal::None,
 706            });
 707        }
 708        self.update_selections(selections, false, cx);
 709        Ok(())
 710    }
 711
 712    pub fn insert(&mut self, action: &Insert, cx: &mut ViewContext<Self>) {
 713        let mut old_selections = SmallVec::<[_; 32]>::new();
 714        {
 715            let buffer = self.buffer.read(cx);
 716            for selection in self.selections(cx.as_ref()) {
 717                let start = selection.start.to_offset(buffer);
 718                let end = selection.end.to_offset(buffer);
 719                old_selections.push((selection.id, start..end));
 720            }
 721        }
 722
 723        self.start_transaction(cx);
 724        let mut new_selections = Vec::new();
 725        self.buffer.update(cx, |buffer, cx| {
 726            let edit_ranges = old_selections.iter().map(|(_, range)| range.clone());
 727            buffer.edit(edit_ranges, action.0.as_str(), cx);
 728            let text_len = action.0.len() as isize;
 729            let mut delta = 0_isize;
 730            new_selections = old_selections
 731                .into_iter()
 732                .map(|(id, range)| {
 733                    let start = range.start as isize;
 734                    let end = range.end as isize;
 735                    let anchor = buffer.anchor_before((start + delta + text_len) as usize);
 736                    let deleted_count = end - start;
 737                    delta += text_len - deleted_count;
 738                    Selection {
 739                        id,
 740                        start: anchor.clone(),
 741                        end: anchor,
 742                        reversed: false,
 743                        goal: SelectionGoal::None,
 744                    }
 745                })
 746                .collect();
 747        });
 748
 749        self.update_selections(new_selections, true, cx);
 750        self.end_transaction(cx);
 751    }
 752
 753    pub fn clear(&mut self, cx: &mut ViewContext<Self>) {
 754        self.start_transaction(cx);
 755        self.select_all(&SelectAll, cx);
 756        self.insert(&Insert(String::new()), cx);
 757        self.end_transaction(cx);
 758    }
 759
 760    fn newline(&mut self, Newline(insert_newline): &Newline, cx: &mut ViewContext<Self>) {
 761        match self.mode {
 762            EditorMode::SingleLine => cx.propagate_action(),
 763            EditorMode::AutoHeight => {
 764                if *insert_newline {
 765                    self.insert(&Insert("\n".into()), cx);
 766                } else {
 767                    cx.propagate_action();
 768                }
 769            }
 770            EditorMode::Full => self.insert(&Insert("\n".into()), cx),
 771        }
 772    }
 773
 774    pub fn backspace(&mut self, _: &Backspace, cx: &mut ViewContext<Self>) {
 775        self.start_transaction(cx);
 776        let mut selections = self.selections(cx.as_ref()).to_vec();
 777        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 778        {
 779            let buffer = self.buffer.read(cx);
 780            for selection in &mut selections {
 781                let range = selection.point_range(buffer);
 782                if range.start == range.end {
 783                    let head = selection.head().to_display_point(&display_map, Bias::Left);
 784                    let cursor = display_map
 785                        .anchor_before(movement::left(&display_map, head).unwrap(), Bias::Left);
 786                    selection.set_head(&buffer, cursor);
 787                    selection.goal = SelectionGoal::None;
 788                }
 789            }
 790        }
 791
 792        self.update_selections(selections, true, cx);
 793        self.insert(&Insert(String::new()), cx);
 794        self.end_transaction(cx);
 795    }
 796
 797    pub fn delete(&mut self, _: &Delete, cx: &mut ViewContext<Self>) {
 798        self.start_transaction(cx);
 799        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 800        let mut selections = self.selections(cx.as_ref()).to_vec();
 801        {
 802            let buffer = self.buffer.read(cx);
 803            for selection in &mut selections {
 804                let range = selection.point_range(buffer);
 805                if range.start == range.end {
 806                    let head = selection.head().to_display_point(&display_map, Bias::Left);
 807                    let cursor = display_map
 808                        .anchor_before(movement::right(&display_map, head).unwrap(), Bias::Right);
 809                    selection.set_head(&buffer, cursor);
 810                    selection.goal = SelectionGoal::None;
 811                }
 812            }
 813        }
 814
 815        self.update_selections(selections, true, cx);
 816        self.insert(&Insert(String::new()), cx);
 817        self.end_transaction(cx);
 818    }
 819
 820    pub fn delete_line(&mut self, _: &DeleteLine, cx: &mut ViewContext<Self>) {
 821        self.start_transaction(cx);
 822
 823        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 824        let app = cx.as_ref();
 825        let buffer = self.buffer.read(app);
 826
 827        let mut new_cursors = Vec::new();
 828        let mut edit_ranges = Vec::new();
 829
 830        let mut selections = self.selections(app).iter().peekable();
 831        while let Some(selection) = selections.next() {
 832            let mut rows = selection.spanned_rows(false, &display_map).buffer_rows;
 833            let goal_display_column = selection
 834                .head()
 835                .to_display_point(&display_map, Bias::Left)
 836                .column();
 837
 838            // Accumulate contiguous regions of rows that we want to delete.
 839            while let Some(next_selection) = selections.peek() {
 840                let next_rows = next_selection.spanned_rows(false, &display_map).buffer_rows;
 841                if next_rows.start <= rows.end {
 842                    rows.end = next_rows.end;
 843                    selections.next().unwrap();
 844                } else {
 845                    break;
 846                }
 847            }
 848
 849            let mut edit_start = Point::new(rows.start, 0).to_offset(buffer);
 850            let edit_end;
 851            let cursor_buffer_row;
 852            if buffer.max_point().row >= rows.end {
 853                // If there's a line after the range, delete the \n from the end of the row range
 854                // and position the cursor on the next line.
 855                edit_end = Point::new(rows.end, 0).to_offset(buffer);
 856                cursor_buffer_row = rows.end;
 857            } else {
 858                // If there isn't a line after the range, delete the \n from the line before the
 859                // start of the row range and position the cursor there.
 860                edit_start = edit_start.saturating_sub(1);
 861                edit_end = buffer.len();
 862                cursor_buffer_row = rows.start.saturating_sub(1);
 863            }
 864
 865            let mut cursor =
 866                Point::new(cursor_buffer_row, 0).to_display_point(&display_map, Bias::Left);
 867            *cursor.column_mut() =
 868                cmp::min(goal_display_column, display_map.line_len(cursor.row()));
 869
 870            new_cursors.push((
 871                selection.id,
 872                cursor.to_buffer_point(&display_map, Bias::Left),
 873            ));
 874            edit_ranges.push(edit_start..edit_end);
 875        }
 876
 877        new_cursors.sort_unstable_by_key(|(_, range)| range.clone());
 878        let new_selections = new_cursors
 879            .into_iter()
 880            .map(|(id, cursor)| {
 881                let anchor = buffer.anchor_before(cursor);
 882                Selection {
 883                    id,
 884                    start: anchor.clone(),
 885                    end: anchor,
 886                    reversed: false,
 887                    goal: SelectionGoal::None,
 888                }
 889            })
 890            .collect();
 891        self.buffer
 892            .update(cx, |buffer, cx| buffer.edit(edit_ranges, "", cx));
 893        self.update_selections(new_selections, true, cx);
 894        self.end_transaction(cx);
 895    }
 896
 897    pub fn duplicate_line(&mut self, _: &DuplicateLine, cx: &mut ViewContext<Self>) {
 898        self.start_transaction(cx);
 899
 900        let mut selections = self.selections(cx.as_ref()).to_vec();
 901        {
 902            // Temporarily bias selections right to allow newly duplicate lines to push them down
 903            // when the selections are at the beginning of a line.
 904            let buffer = self.buffer.read(cx);
 905            for selection in &mut selections {
 906                selection.start = selection.start.bias_right(buffer);
 907                selection.end = selection.end.bias_right(buffer);
 908            }
 909        }
 910        self.update_selections(selections.clone(), false, cx);
 911
 912        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 913        let buffer = self.buffer.read(cx);
 914
 915        let mut edits = Vec::new();
 916        let mut selections_iter = selections.iter_mut().peekable();
 917        while let Some(selection) = selections_iter.next() {
 918            // Avoid duplicating the same lines twice.
 919            let mut rows = selection.spanned_rows(false, &display_map).buffer_rows;
 920            while let Some(next_selection) = selections_iter.peek() {
 921                let next_rows = next_selection.spanned_rows(false, &display_map).buffer_rows;
 922                if next_rows.start <= rows.end - 1 {
 923                    rows.end = next_rows.end;
 924                    selections_iter.next().unwrap();
 925                } else {
 926                    break;
 927                }
 928            }
 929
 930            // Copy the text from the selected row region and splice it at the start of the region.
 931            let start = Point::new(rows.start, 0);
 932            let end = Point::new(rows.end - 1, buffer.line_len(rows.end - 1));
 933            let text = buffer
 934                .text_for_range(start..end)
 935                .chain(Some("\n"))
 936                .collect::<String>();
 937            edits.push((start, text));
 938        }
 939
 940        self.buffer.update(cx, |buffer, cx| {
 941            for (offset, text) in edits.into_iter().rev() {
 942                buffer.edit(Some(offset..offset), text, cx);
 943            }
 944        });
 945
 946        // Restore bias on selections.
 947        let buffer = self.buffer.read(cx);
 948        for selection in &mut selections {
 949            selection.start = selection.start.bias_left(buffer);
 950            selection.end = selection.end.bias_left(buffer);
 951        }
 952        self.update_selections(selections, true, cx);
 953
 954        self.end_transaction(cx);
 955    }
 956
 957    pub fn move_line_up(&mut self, _: &MoveLineUp, cx: &mut ViewContext<Self>) {
 958        self.start_transaction(cx);
 959
 960        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
 961        let app = cx.as_ref();
 962        let buffer = self.buffer.read(cx);
 963
 964        let mut edits = Vec::new();
 965        let mut new_selection_ranges = Vec::new();
 966        let mut old_folds = Vec::new();
 967        let mut new_folds = Vec::new();
 968
 969        let mut selections = self.selections(app).iter().peekable();
 970        let mut contiguous_selections = Vec::new();
 971        while let Some(selection) = selections.next() {
 972            // Accumulate contiguous regions of rows that we want to move.
 973            contiguous_selections.push(selection.point_range(buffer));
 974            let SpannedRows {
 975                mut buffer_rows,
 976                mut display_rows,
 977            } = selection.spanned_rows(false, &display_map);
 978
 979            while let Some(next_selection) = selections.peek() {
 980                let SpannedRows {
 981                    buffer_rows: next_buffer_rows,
 982                    display_rows: next_display_rows,
 983                } = next_selection.spanned_rows(false, &display_map);
 984                if next_buffer_rows.start <= buffer_rows.end {
 985                    buffer_rows.end = next_buffer_rows.end;
 986                    display_rows.end = next_display_rows.end;
 987                    contiguous_selections.push(next_selection.point_range(buffer));
 988                    selections.next().unwrap();
 989                } else {
 990                    break;
 991                }
 992            }
 993
 994            // Cut the text from the selected rows and paste it at the start of the previous line.
 995            if display_rows.start != 0 {
 996                let start = Point::new(buffer_rows.start, 0).to_offset(buffer);
 997                let end = Point::new(buffer_rows.end - 1, buffer.line_len(buffer_rows.end - 1))
 998                    .to_offset(buffer);
 999
1000                let prev_row_display_start = DisplayPoint::new(display_rows.start - 1, 0);
1001                let prev_row_buffer_start = display_map.prev_row_boundary(prev_row_display_start).1;
1002                let prev_row_buffer_start_offset = prev_row_buffer_start.to_offset(buffer);
1003
1004                let mut text = String::new();
1005                text.extend(buffer.text_for_range(start..end));
1006                text.push('\n');
1007                edits.push((
1008                    prev_row_buffer_start_offset..prev_row_buffer_start_offset,
1009                    text,
1010                ));
1011                edits.push((start - 1..end, String::new()));
1012
1013                let row_delta = buffer_rows.start - prev_row_buffer_start.row;
1014
1015                // Move selections up.
1016                for range in &mut contiguous_selections {
1017                    range.start.row -= row_delta;
1018                    range.end.row -= row_delta;
1019                }
1020
1021                // Move folds up.
1022                old_folds.push(start..end);
1023                for fold in display_map.folds_in_range(start..end) {
1024                    let mut start = fold.start.to_point(buffer);
1025                    let mut end = fold.end.to_point(buffer);
1026                    start.row -= row_delta;
1027                    end.row -= row_delta;
1028                    new_folds.push(start..end);
1029                }
1030            }
1031
1032            new_selection_ranges.extend(contiguous_selections.drain(..));
1033        }
1034
1035        self.unfold_ranges(old_folds, cx);
1036        self.buffer.update(cx, |buffer, cx| {
1037            for (range, text) in edits.into_iter().rev() {
1038                buffer.edit(Some(range), text, cx);
1039            }
1040        });
1041        self.fold_ranges(new_folds, cx);
1042        self.select_ranges(new_selection_ranges, true, cx);
1043
1044        self.end_transaction(cx);
1045    }
1046
1047    pub fn move_line_down(&mut self, _: &MoveLineDown, cx: &mut ViewContext<Self>) {
1048        self.start_transaction(cx);
1049
1050        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1051        let app = cx.as_ref();
1052        let buffer = self.buffer.read(cx);
1053
1054        let mut edits = Vec::new();
1055        let mut new_selection_ranges = Vec::new();
1056        let mut old_folds = Vec::new();
1057        let mut new_folds = Vec::new();
1058
1059        let mut selections = self.selections(app).iter().peekable();
1060        let mut contiguous_selections = Vec::new();
1061        while let Some(selection) = selections.next() {
1062            // Accumulate contiguous regions of rows that we want to move.
1063            contiguous_selections.push(selection.point_range(buffer));
1064            let SpannedRows {
1065                mut buffer_rows,
1066                mut display_rows,
1067            } = selection.spanned_rows(false, &display_map);
1068            while let Some(next_selection) = selections.peek() {
1069                let SpannedRows {
1070                    buffer_rows: next_buffer_rows,
1071                    display_rows: next_display_rows,
1072                } = next_selection.spanned_rows(false, &display_map);
1073                if next_buffer_rows.start <= buffer_rows.end {
1074                    buffer_rows.end = next_buffer_rows.end;
1075                    display_rows.end = next_display_rows.end;
1076                    contiguous_selections.push(next_selection.point_range(buffer));
1077                    selections.next().unwrap();
1078                } else {
1079                    break;
1080                }
1081            }
1082
1083            // Cut the text from the selected rows and paste it at the end of the next line.
1084            if display_rows.end <= display_map.max_point().row() {
1085                let start = Point::new(buffer_rows.start, 0).to_offset(buffer);
1086                let end = Point::new(buffer_rows.end - 1, buffer.line_len(buffer_rows.end - 1))
1087                    .to_offset(buffer);
1088
1089                let next_row_display_end =
1090                    DisplayPoint::new(display_rows.end, display_map.line_len(display_rows.end));
1091                let next_row_buffer_end = display_map.next_row_boundary(next_row_display_end).1;
1092                let next_row_buffer_end_offset = next_row_buffer_end.to_offset(buffer);
1093
1094                let mut text = String::new();
1095                text.push('\n');
1096                text.extend(buffer.text_for_range(start..end));
1097                edits.push((start..end + 1, String::new()));
1098                edits.push((next_row_buffer_end_offset..next_row_buffer_end_offset, text));
1099
1100                let row_delta = next_row_buffer_end.row - buffer_rows.end + 1;
1101
1102                // Move selections down.
1103                for range in &mut contiguous_selections {
1104                    range.start.row += row_delta;
1105                    range.end.row += row_delta;
1106                }
1107
1108                // Move folds down.
1109                old_folds.push(start..end);
1110                for fold in display_map.folds_in_range(start..end) {
1111                    let mut start = fold.start.to_point(buffer);
1112                    let mut end = fold.end.to_point(buffer);
1113                    start.row += row_delta;
1114                    end.row += row_delta;
1115                    new_folds.push(start..end);
1116                }
1117            }
1118
1119            new_selection_ranges.extend(contiguous_selections.drain(..));
1120        }
1121
1122        self.unfold_ranges(old_folds, cx);
1123        self.buffer.update(cx, |buffer, cx| {
1124            for (range, text) in edits.into_iter().rev() {
1125                buffer.edit(Some(range), text, cx);
1126            }
1127        });
1128        self.fold_ranges(new_folds, cx);
1129        self.select_ranges(new_selection_ranges, true, cx);
1130
1131        self.end_transaction(cx);
1132    }
1133
1134    pub fn cut(&mut self, _: &Cut, cx: &mut ViewContext<Self>) {
1135        self.start_transaction(cx);
1136        let mut text = String::new();
1137        let mut selections = self.selections(cx.as_ref()).to_vec();
1138        let mut clipboard_selections = Vec::with_capacity(selections.len());
1139        {
1140            let buffer = self.buffer.read(cx);
1141            let max_point = buffer.max_point();
1142            for selection in &mut selections {
1143                let mut start = selection.start.to_point(buffer);
1144                let mut end = selection.end.to_point(buffer);
1145                let is_entire_line = start == end;
1146                if is_entire_line {
1147                    start = Point::new(start.row, 0);
1148                    end = cmp::min(max_point, Point::new(start.row + 1, 0));
1149                    selection.start = buffer.anchor_before(start);
1150                    selection.end = buffer.anchor_before(end);
1151                }
1152                let mut len = 0;
1153                for chunk in buffer.text_for_range(start..end) {
1154                    text.push_str(chunk);
1155                    len += chunk.len();
1156                }
1157                clipboard_selections.push(ClipboardSelection {
1158                    len,
1159                    is_entire_line,
1160                });
1161            }
1162        }
1163        self.update_selections(selections, true, cx);
1164        self.insert(&Insert(String::new()), cx);
1165        self.end_transaction(cx);
1166
1167        cx.as_mut()
1168            .write_to_clipboard(ClipboardItem::new(text).with_metadata(clipboard_selections));
1169    }
1170
1171    pub fn copy(&mut self, _: &Copy, cx: &mut ViewContext<Self>) {
1172        let buffer = self.buffer.read(cx);
1173        let max_point = buffer.max_point();
1174        let mut text = String::new();
1175        let selections = self.selections(cx.as_ref());
1176        let mut clipboard_selections = Vec::with_capacity(selections.len());
1177        for selection in selections {
1178            let mut start = selection.start.to_point(buffer);
1179            let mut end = selection.end.to_point(buffer);
1180            let is_entire_line = start == end;
1181            if is_entire_line {
1182                start = Point::new(start.row, 0);
1183                end = cmp::min(max_point, Point::new(start.row + 1, 0));
1184            }
1185            let mut len = 0;
1186            for chunk in buffer.text_for_range(start..end) {
1187                text.push_str(chunk);
1188                len += chunk.len();
1189            }
1190            clipboard_selections.push(ClipboardSelection {
1191                len,
1192                is_entire_line,
1193            });
1194        }
1195
1196        cx.as_mut()
1197            .write_to_clipboard(ClipboardItem::new(text).with_metadata(clipboard_selections));
1198    }
1199
1200    pub fn paste(&mut self, _: &Paste, cx: &mut ViewContext<Self>) {
1201        if let Some(item) = cx.as_mut().read_from_clipboard() {
1202            let clipboard_text = item.text();
1203            if let Some(mut clipboard_selections) = item.metadata::<Vec<ClipboardSelection>>() {
1204                let selections = self.selections(cx.as_ref()).to_vec();
1205                if clipboard_selections.len() != selections.len() {
1206                    let merged_selection = ClipboardSelection {
1207                        len: clipboard_selections.iter().map(|s| s.len).sum(),
1208                        is_entire_line: clipboard_selections.iter().all(|s| s.is_entire_line),
1209                    };
1210                    clipboard_selections.clear();
1211                    clipboard_selections.push(merged_selection);
1212                }
1213
1214                self.start_transaction(cx);
1215                let mut new_selections = Vec::with_capacity(selections.len());
1216                let mut clipboard_chars = clipboard_text.chars().cycle();
1217                for (selection, clipboard_selection) in
1218                    selections.iter().zip(clipboard_selections.iter().cycle())
1219                {
1220                    let to_insert =
1221                        String::from_iter(clipboard_chars.by_ref().take(clipboard_selection.len));
1222
1223                    self.buffer.update(cx, |buffer, cx| {
1224                        let selection_start = selection.start.to_point(&*buffer);
1225                        let selection_end = selection.end.to_point(&*buffer);
1226
1227                        // If the corresponding selection was empty when this slice of the
1228                        // clipboard text was written, then the entire line containing the
1229                        // selection was copied. If this selection is also currently empty,
1230                        // then paste the line before the current line of the buffer.
1231                        let new_selection_start = selection.end.bias_right(buffer);
1232                        if selection_start == selection_end && clipboard_selection.is_entire_line {
1233                            let line_start = Point::new(selection_start.row, 0);
1234                            buffer.edit(Some(line_start..line_start), to_insert, cx);
1235                        } else {
1236                            buffer.edit(Some(&selection.start..&selection.end), to_insert, cx);
1237                        };
1238
1239                        let new_selection_start = new_selection_start.bias_left(buffer);
1240                        new_selections.push(Selection {
1241                            id: selection.id,
1242                            start: new_selection_start.clone(),
1243                            end: new_selection_start,
1244                            reversed: false,
1245                            goal: SelectionGoal::None,
1246                        });
1247                    });
1248                }
1249                self.update_selections(new_selections, true, cx);
1250                self.end_transaction(cx);
1251            } else {
1252                self.insert(&Insert(clipboard_text.into()), cx);
1253            }
1254        }
1255    }
1256
1257    pub fn undo(&mut self, _: &Undo, cx: &mut ViewContext<Self>) {
1258        self.buffer.update(cx, |buffer, cx| buffer.undo(cx));
1259    }
1260
1261    pub fn redo(&mut self, _: &Redo, cx: &mut ViewContext<Self>) {
1262        self.buffer.update(cx, |buffer, cx| buffer.redo(cx));
1263    }
1264
1265    pub fn move_left(&mut self, _: &MoveLeft, cx: &mut ViewContext<Self>) {
1266        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1267        let app = cx.as_ref();
1268        let mut selections = self.selections(app).to_vec();
1269        {
1270            for selection in &mut selections {
1271                let start = selection.start.to_display_point(&display_map, Bias::Left);
1272                let end = selection.end.to_display_point(&display_map, Bias::Left);
1273
1274                if start != end {
1275                    selection.end = selection.start.clone();
1276                } else {
1277                    let cursor = display_map
1278                        .anchor_before(movement::left(&display_map, start).unwrap(), Bias::Left);
1279                    selection.start = cursor.clone();
1280                    selection.end = cursor;
1281                }
1282                selection.reversed = false;
1283                selection.goal = SelectionGoal::None;
1284            }
1285        }
1286        self.update_selections(selections, true, cx);
1287    }
1288
1289    pub fn select_left(&mut self, _: &SelectLeft, cx: &mut ViewContext<Self>) {
1290        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1291        let mut selections = self.selections(cx.as_ref()).to_vec();
1292        {
1293            let buffer = self.buffer.read(cx);
1294            for selection in &mut selections {
1295                let head = selection.head().to_display_point(&display_map, Bias::Left);
1296                let cursor = display_map
1297                    .anchor_before(movement::left(&display_map, head).unwrap(), Bias::Left);
1298                selection.set_head(&buffer, cursor);
1299                selection.goal = SelectionGoal::None;
1300            }
1301        }
1302        self.update_selections(selections, true, cx);
1303    }
1304
1305    pub fn move_right(&mut self, _: &MoveRight, cx: &mut ViewContext<Self>) {
1306        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1307        let mut selections = self.selections(cx.as_ref()).to_vec();
1308        {
1309            for selection in &mut selections {
1310                let start = selection.start.to_display_point(&display_map, Bias::Left);
1311                let end = selection.end.to_display_point(&display_map, Bias::Left);
1312
1313                if start != end {
1314                    selection.start = selection.end.clone();
1315                } else {
1316                    let cursor = display_map
1317                        .anchor_before(movement::right(&display_map, end).unwrap(), Bias::Right);
1318                    selection.start = cursor.clone();
1319                    selection.end = cursor;
1320                }
1321                selection.reversed = false;
1322                selection.goal = SelectionGoal::None;
1323            }
1324        }
1325        self.update_selections(selections, true, cx);
1326    }
1327
1328    pub fn select_right(&mut self, _: &SelectRight, cx: &mut ViewContext<Self>) {
1329        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1330        let mut selections = self.selections(cx.as_ref()).to_vec();
1331        {
1332            let app = cx.as_ref();
1333            let buffer = self.buffer.read(app);
1334            for selection in &mut selections {
1335                let head = selection.head().to_display_point(&display_map, Bias::Left);
1336                let cursor = display_map
1337                    .anchor_before(movement::right(&display_map, head).unwrap(), Bias::Right);
1338                selection.set_head(&buffer, cursor);
1339                selection.goal = SelectionGoal::None;
1340            }
1341        }
1342        self.update_selections(selections, true, cx);
1343    }
1344
1345    pub fn move_up(&mut self, _: &MoveUp, cx: &mut ViewContext<Self>) {
1346        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1347        if matches!(self.mode, EditorMode::SingleLine) {
1348            cx.propagate_action();
1349        } else {
1350            let mut selections = self.selections(cx.as_ref()).to_vec();
1351            {
1352                for selection in &mut selections {
1353                    let start = selection.start.to_display_point(&display_map, Bias::Left);
1354                    let end = selection.end.to_display_point(&display_map, Bias::Left);
1355                    if start != end {
1356                        selection.goal = SelectionGoal::None;
1357                    }
1358
1359                    let (start, goal) = movement::up(&display_map, start, selection.goal).unwrap();
1360                    let cursor = display_map.anchor_before(start, Bias::Left);
1361                    selection.start = cursor.clone();
1362                    selection.end = cursor;
1363                    selection.goal = goal;
1364                    selection.reversed = false;
1365                }
1366            }
1367            self.update_selections(selections, true, cx);
1368        }
1369    }
1370
1371    pub fn select_up(&mut self, _: &SelectUp, cx: &mut ViewContext<Self>) {
1372        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1373        let mut selections = self.selections(cx.as_ref()).to_vec();
1374        {
1375            let app = cx.as_ref();
1376            let buffer = self.buffer.read(app);
1377            for selection in &mut selections {
1378                let head = selection.head().to_display_point(&display_map, Bias::Left);
1379                let (head, goal) = movement::up(&display_map, head, selection.goal).unwrap();
1380                selection.set_head(&buffer, display_map.anchor_before(head, Bias::Left));
1381                selection.goal = goal;
1382            }
1383        }
1384        self.update_selections(selections, true, cx);
1385    }
1386
1387    pub fn move_down(&mut self, _: &MoveDown, cx: &mut ViewContext<Self>) {
1388        if matches!(self.mode, EditorMode::SingleLine) {
1389            cx.propagate_action();
1390        } else {
1391            let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1392            let mut selections = self.selections(cx.as_ref()).to_vec();
1393            {
1394                for selection in &mut selections {
1395                    let start = selection.start.to_display_point(&display_map, Bias::Left);
1396                    let end = selection.end.to_display_point(&display_map, Bias::Left);
1397                    if start != end {
1398                        selection.goal = SelectionGoal::None;
1399                    }
1400
1401                    let (start, goal) = movement::down(&display_map, end, selection.goal).unwrap();
1402                    let cursor = display_map.anchor_before(start, Bias::Right);
1403                    selection.start = cursor.clone();
1404                    selection.end = cursor;
1405                    selection.goal = goal;
1406                    selection.reversed = false;
1407                }
1408            }
1409            self.update_selections(selections, true, cx);
1410        }
1411    }
1412
1413    pub fn select_down(&mut self, _: &SelectDown, cx: &mut ViewContext<Self>) {
1414        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1415        let mut selections = self.selections(cx).to_vec();
1416        {
1417            let app = cx.as_ref();
1418            let buffer = self.buffer.read(app);
1419            for selection in &mut selections {
1420                let head = selection.head().to_display_point(&display_map, Bias::Left);
1421                let (head, goal) = movement::down(&display_map, head, selection.goal).unwrap();
1422                selection.set_head(&buffer, display_map.anchor_before(head, Bias::Right));
1423                selection.goal = goal;
1424            }
1425        }
1426        self.update_selections(selections, true, cx);
1427    }
1428
1429    pub fn move_to_previous_word_boundary(
1430        &mut self,
1431        _: &MoveToPreviousWordBoundary,
1432        cx: &mut ViewContext<Self>,
1433    ) {
1434        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1435        let mut selections = self.selections(cx).to_vec();
1436        {
1437            for selection in &mut selections {
1438                let head = selection.head().to_display_point(&display_map, Bias::Left);
1439                let new_head = movement::prev_word_boundary(&display_map, head).unwrap();
1440                let anchor = display_map.anchor_before(new_head, Bias::Left);
1441                selection.start = anchor.clone();
1442                selection.end = anchor;
1443                selection.reversed = false;
1444                selection.goal = SelectionGoal::None;
1445            }
1446        }
1447        self.update_selections(selections, true, cx);
1448    }
1449
1450    pub fn select_to_previous_word_boundary(
1451        &mut self,
1452        _: &SelectToPreviousWordBoundary,
1453        cx: &mut ViewContext<Self>,
1454    ) {
1455        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1456        let mut selections = self.selections(cx).to_vec();
1457        {
1458            let buffer = self.buffer.read(cx);
1459            for selection in &mut selections {
1460                let head = selection.head().to_display_point(&display_map, Bias::Left);
1461                let new_head = movement::prev_word_boundary(&display_map, head).unwrap();
1462                let anchor = display_map.anchor_before(new_head, Bias::Left);
1463                selection.set_head(buffer, anchor);
1464                selection.goal = SelectionGoal::None;
1465            }
1466        }
1467        self.update_selections(selections, true, cx);
1468    }
1469
1470    pub fn delete_to_previous_word_boundary(
1471        &mut self,
1472        _: &DeleteToPreviousWordBoundary,
1473        cx: &mut ViewContext<Self>,
1474    ) {
1475        self.start_transaction(cx);
1476        self.select_to_previous_word_boundary(&SelectToPreviousWordBoundary, cx);
1477        self.backspace(&Backspace, cx);
1478        self.end_transaction(cx);
1479    }
1480
1481    pub fn move_to_next_word_boundary(
1482        &mut self,
1483        _: &MoveToNextWordBoundary,
1484        cx: &mut ViewContext<Self>,
1485    ) {
1486        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1487        let mut selections = self.selections(cx).to_vec();
1488        {
1489            for selection in &mut selections {
1490                let head = selection.head().to_display_point(&display_map, Bias::Left);
1491                let new_head = movement::next_word_boundary(&display_map, head).unwrap();
1492                let anchor = display_map.anchor_before(new_head, Bias::Left);
1493                selection.start = anchor.clone();
1494                selection.end = anchor;
1495                selection.reversed = false;
1496                selection.goal = SelectionGoal::None;
1497            }
1498        }
1499        self.update_selections(selections, true, cx);
1500    }
1501
1502    pub fn select_to_next_word_boundary(
1503        &mut self,
1504        _: &SelectToNextWordBoundary,
1505        cx: &mut ViewContext<Self>,
1506    ) {
1507        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1508        let mut selections = self.selections(cx).to_vec();
1509        {
1510            let buffer = self.buffer.read(cx);
1511            for selection in &mut selections {
1512                let head = selection.head().to_display_point(&display_map, Bias::Left);
1513                let new_head = movement::next_word_boundary(&display_map, head).unwrap();
1514                let anchor = display_map.anchor_before(new_head, Bias::Left);
1515                selection.set_head(buffer, anchor);
1516                selection.goal = SelectionGoal::None;
1517            }
1518        }
1519        self.update_selections(selections, true, cx);
1520    }
1521
1522    pub fn delete_to_next_word_boundary(
1523        &mut self,
1524        _: &DeleteToNextWordBoundary,
1525        cx: &mut ViewContext<Self>,
1526    ) {
1527        self.start_transaction(cx);
1528        self.select_to_next_word_boundary(&SelectToNextWordBoundary, cx);
1529        self.delete(&Delete, cx);
1530        self.end_transaction(cx);
1531    }
1532
1533    pub fn move_to_beginning_of_line(
1534        &mut self,
1535        _: &MoveToBeginningOfLine,
1536        cx: &mut ViewContext<Self>,
1537    ) {
1538        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1539        let mut selections = self.selections(cx).to_vec();
1540        {
1541            for selection in &mut selections {
1542                let head = selection.head().to_display_point(&display_map, Bias::Left);
1543                let new_head = movement::line_beginning(&display_map, head, true).unwrap();
1544                let anchor = display_map.anchor_before(new_head, Bias::Left);
1545                selection.start = anchor.clone();
1546                selection.end = anchor;
1547                selection.reversed = false;
1548                selection.goal = SelectionGoal::None;
1549            }
1550        }
1551        self.update_selections(selections, true, cx);
1552    }
1553
1554    pub fn select_to_beginning_of_line(
1555        &mut self,
1556        SelectToBeginningOfLine(toggle_indent): &SelectToBeginningOfLine,
1557        cx: &mut ViewContext<Self>,
1558    ) {
1559        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1560        let mut selections = self.selections(cx).to_vec();
1561        {
1562            let buffer = self.buffer.read(cx);
1563            for selection in &mut selections {
1564                let head = selection.head().to_display_point(&display_map, Bias::Left);
1565                let new_head =
1566                    movement::line_beginning(&display_map, head, *toggle_indent).unwrap();
1567                let anchor = display_map.anchor_before(new_head, Bias::Left);
1568                selection.set_head(buffer, anchor);
1569                selection.goal = SelectionGoal::None;
1570            }
1571        }
1572        self.update_selections(selections, true, cx);
1573    }
1574
1575    pub fn delete_to_beginning_of_line(
1576        &mut self,
1577        _: &DeleteToBeginningOfLine,
1578        cx: &mut ViewContext<Self>,
1579    ) {
1580        self.start_transaction(cx);
1581        self.select_to_beginning_of_line(&SelectToBeginningOfLine(false), cx);
1582        self.backspace(&Backspace, cx);
1583        self.end_transaction(cx);
1584    }
1585
1586    pub fn move_to_end_of_line(&mut self, _: &MoveToEndOfLine, cx: &mut ViewContext<Self>) {
1587        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1588        let mut selections = self.selections(cx).to_vec();
1589        {
1590            for selection in &mut selections {
1591                let head = selection.head().to_display_point(&display_map, Bias::Left);
1592                let new_head = movement::line_end(&display_map, head).unwrap();
1593                let anchor = display_map.anchor_before(new_head, Bias::Left);
1594                selection.start = anchor.clone();
1595                selection.end = anchor;
1596                selection.reversed = false;
1597                selection.goal = SelectionGoal::None;
1598            }
1599        }
1600        self.update_selections(selections, true, cx);
1601    }
1602
1603    pub fn select_to_end_of_line(&mut self, _: &SelectToEndOfLine, cx: &mut ViewContext<Self>) {
1604        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1605        let mut selections = self.selections(cx).to_vec();
1606        {
1607            let buffer = self.buffer.read(cx);
1608            for selection in &mut selections {
1609                let head = selection.head().to_display_point(&display_map, Bias::Left);
1610                let new_head = movement::line_end(&display_map, head).unwrap();
1611                let anchor = display_map.anchor_before(new_head, Bias::Left);
1612                selection.set_head(buffer, anchor);
1613                selection.goal = SelectionGoal::None;
1614            }
1615        }
1616        self.update_selections(selections, true, cx);
1617    }
1618
1619    pub fn delete_to_end_of_line(&mut self, _: &DeleteToEndOfLine, cx: &mut ViewContext<Self>) {
1620        self.start_transaction(cx);
1621        self.select_to_end_of_line(&SelectToEndOfLine, cx);
1622        self.delete(&Delete, cx);
1623        self.end_transaction(cx);
1624    }
1625
1626    pub fn cut_to_end_of_line(&mut self, _: &CutToEndOfLine, cx: &mut ViewContext<Self>) {
1627        self.start_transaction(cx);
1628        self.select_to_end_of_line(&SelectToEndOfLine, cx);
1629        self.cut(&Cut, cx);
1630        self.end_transaction(cx);
1631    }
1632
1633    pub fn move_to_beginning(&mut self, _: &MoveToBeginning, cx: &mut ViewContext<Self>) {
1634        let buffer = self.buffer.read(cx);
1635        let cursor = buffer.anchor_before(Point::new(0, 0));
1636        let selection = Selection {
1637            id: post_inc(&mut self.next_selection_id),
1638            start: cursor.clone(),
1639            end: cursor,
1640            reversed: false,
1641            goal: SelectionGoal::None,
1642        };
1643        self.update_selections(vec![selection], true, cx);
1644    }
1645
1646    pub fn select_to_beginning(&mut self, _: &SelectToBeginning, cx: &mut ViewContext<Self>) {
1647        let mut selection = self.selections(cx.as_ref()).last().unwrap().clone();
1648        selection.set_head(self.buffer.read(cx), Anchor::min());
1649        self.update_selections(vec![selection], true, cx);
1650    }
1651
1652    pub fn move_to_end(&mut self, _: &MoveToEnd, cx: &mut ViewContext<Self>) {
1653        let buffer = self.buffer.read(cx);
1654        let cursor = buffer.anchor_before(buffer.max_point());
1655        let selection = Selection {
1656            id: post_inc(&mut self.next_selection_id),
1657            start: cursor.clone(),
1658            end: cursor,
1659            reversed: false,
1660            goal: SelectionGoal::None,
1661        };
1662        self.update_selections(vec![selection], true, cx);
1663    }
1664
1665    pub fn select_to_end(&mut self, _: &SelectToEnd, cx: &mut ViewContext<Self>) {
1666        let mut selection = self.selections(cx.as_ref()).last().unwrap().clone();
1667        selection.set_head(self.buffer.read(cx), Anchor::max());
1668        self.update_selections(vec![selection], true, cx);
1669    }
1670
1671    pub fn select_all(&mut self, _: &SelectAll, cx: &mut ViewContext<Self>) {
1672        let selection = Selection {
1673            id: post_inc(&mut self.next_selection_id),
1674            start: Anchor::min(),
1675            end: Anchor::max(),
1676            reversed: false,
1677            goal: SelectionGoal::None,
1678        };
1679        self.update_selections(vec![selection], false, cx);
1680    }
1681
1682    pub fn select_line(&mut self, _: &SelectLine, cx: &mut ViewContext<Self>) {
1683        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1684        let buffer = self.buffer.read(cx);
1685        let mut selections = self.selections(cx).to_vec();
1686        let max_point = buffer.max_point();
1687        for selection in &mut selections {
1688            let rows = selection.spanned_rows(true, &display_map).buffer_rows;
1689            selection.start = buffer.anchor_before(Point::new(rows.start, 0));
1690            selection.end = buffer.anchor_before(cmp::min(max_point, Point::new(rows.end, 0)));
1691            selection.reversed = false;
1692        }
1693        self.update_selections(selections, true, cx);
1694    }
1695
1696    pub fn split_selection_into_lines(
1697        &mut self,
1698        _: &SplitSelectionIntoLines,
1699        cx: &mut ViewContext<Self>,
1700    ) {
1701        let app = cx.as_ref();
1702        let buffer = self.buffer.read(app);
1703
1704        let mut to_unfold = Vec::new();
1705        let mut new_selections = Vec::new();
1706        for selection in self.selections(app) {
1707            let range = selection.point_range(buffer).sorted();
1708            if range.start.row != range.end.row {
1709                new_selections.push(Selection {
1710                    id: post_inc(&mut self.next_selection_id),
1711                    start: selection.start.clone(),
1712                    end: selection.start.clone(),
1713                    reversed: false,
1714                    goal: SelectionGoal::None,
1715                });
1716            }
1717            for row in range.start.row + 1..range.end.row {
1718                let cursor = buffer.anchor_before(Point::new(row, buffer.line_len(row)));
1719                new_selections.push(Selection {
1720                    id: post_inc(&mut self.next_selection_id),
1721                    start: cursor.clone(),
1722                    end: cursor,
1723                    reversed: false,
1724                    goal: SelectionGoal::None,
1725                });
1726            }
1727            new_selections.push(Selection {
1728                id: selection.id,
1729                start: selection.end.clone(),
1730                end: selection.end.clone(),
1731                reversed: false,
1732                goal: SelectionGoal::None,
1733            });
1734            to_unfold.push(range);
1735        }
1736        self.unfold_ranges(to_unfold, cx);
1737        self.update_selections(new_selections, true, cx);
1738    }
1739
1740    pub fn add_selection_above(&mut self, _: &AddSelectionAbove, cx: &mut ViewContext<Self>) {
1741        self.add_selection(true, cx);
1742    }
1743
1744    pub fn add_selection_below(&mut self, _: &AddSelectionBelow, cx: &mut ViewContext<Self>) {
1745        self.add_selection(false, cx);
1746    }
1747
1748    fn add_selection(&mut self, above: bool, cx: &mut ViewContext<Self>) {
1749        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1750        let mut selections = self.selections(cx).to_vec();
1751        let mut state = self.add_selections_state.take().unwrap_or_else(|| {
1752            let oldest_selection = selections.iter().min_by_key(|s| s.id).unwrap().clone();
1753            let range = oldest_selection.display_range(&display_map).sorted();
1754            let columns = cmp::min(range.start.column(), range.end.column())
1755                ..cmp::max(range.start.column(), range.end.column());
1756
1757            selections.clear();
1758            let mut stack = Vec::new();
1759            for row in range.start.row()..=range.end.row() {
1760                if let Some(selection) = self.build_columnar_selection(
1761                    &display_map,
1762                    row,
1763                    &columns,
1764                    oldest_selection.reversed,
1765                ) {
1766                    stack.push(selection.id);
1767                    selections.push(selection);
1768                }
1769            }
1770
1771            if above {
1772                stack.reverse();
1773            }
1774
1775            AddSelectionsState { above, stack }
1776        });
1777
1778        let last_added_selection = *state.stack.last().unwrap();
1779        let mut new_selections = Vec::new();
1780        if above == state.above {
1781            let end_row = if above {
1782                0
1783            } else {
1784                display_map.max_point().row()
1785            };
1786
1787            'outer: for selection in selections {
1788                if selection.id == last_added_selection {
1789                    let range = selection.display_range(&display_map).sorted();
1790                    debug_assert_eq!(range.start.row(), range.end.row());
1791                    let mut row = range.start.row();
1792                    let columns = if let SelectionGoal::ColumnRange { start, end } = selection.goal
1793                    {
1794                        start..end
1795                    } else {
1796                        cmp::min(range.start.column(), range.end.column())
1797                            ..cmp::max(range.start.column(), range.end.column())
1798                    };
1799
1800                    while row != end_row {
1801                        if above {
1802                            row -= 1;
1803                        } else {
1804                            row += 1;
1805                        }
1806
1807                        if let Some(new_selection) = self.build_columnar_selection(
1808                            &display_map,
1809                            row,
1810                            &columns,
1811                            selection.reversed,
1812                        ) {
1813                            state.stack.push(new_selection.id);
1814                            if above {
1815                                new_selections.push(new_selection);
1816                                new_selections.push(selection);
1817                            } else {
1818                                new_selections.push(selection);
1819                                new_selections.push(new_selection);
1820                            }
1821
1822                            continue 'outer;
1823                        }
1824                    }
1825                }
1826
1827                new_selections.push(selection);
1828            }
1829        } else {
1830            new_selections = selections;
1831            new_selections.retain(|s| s.id != last_added_selection);
1832            state.stack.pop();
1833        }
1834
1835        self.update_selections(new_selections, true, cx);
1836        if state.stack.len() > 1 {
1837            self.add_selections_state = Some(state);
1838        }
1839    }
1840
1841    pub fn select_larger_syntax_node(
1842        &mut self,
1843        _: &SelectLargerSyntaxNode,
1844        cx: &mut ViewContext<Self>,
1845    ) {
1846        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1847        let buffer = self.buffer.read(cx);
1848
1849        let mut stack = mem::take(&mut self.select_larger_syntax_node_stack);
1850        let mut selected_larger_node = false;
1851        let old_selections = self.selections(cx).to_vec();
1852        let mut new_selection_ranges = Vec::new();
1853        for selection in &old_selections {
1854            let old_range = selection.start.to_offset(buffer)..selection.end.to_offset(buffer);
1855            let mut new_range = old_range.clone();
1856            while let Some(containing_range) = buffer.range_for_syntax_ancestor(new_range.clone()) {
1857                new_range = containing_range;
1858                if !display_map.intersects_fold(new_range.start)
1859                    && !display_map.intersects_fold(new_range.end)
1860                {
1861                    break;
1862                }
1863            }
1864
1865            selected_larger_node |= new_range != old_range;
1866            new_selection_ranges.push((selection.id, new_range, selection.reversed));
1867        }
1868
1869        if selected_larger_node {
1870            stack.push(old_selections);
1871            new_selection_ranges.sort_unstable_by_key(|(_, range, _)| range.start.clone());
1872            let new_selections = new_selection_ranges
1873                .into_iter()
1874                .map(|(id, range, reversed)| Selection {
1875                    id,
1876                    start: buffer.anchor_before(range.start),
1877                    end: buffer.anchor_before(range.end),
1878                    reversed,
1879                    goal: SelectionGoal::None,
1880                })
1881                .collect();
1882            self.update_selections(new_selections, true, cx);
1883        }
1884        self.select_larger_syntax_node_stack = stack;
1885    }
1886
1887    pub fn select_smaller_syntax_node(
1888        &mut self,
1889        _: &SelectSmallerSyntaxNode,
1890        cx: &mut ViewContext<Self>,
1891    ) {
1892        let mut stack = mem::take(&mut self.select_larger_syntax_node_stack);
1893        if let Some(selections) = stack.pop() {
1894            self.update_selections(selections, true, cx);
1895        }
1896        self.select_larger_syntax_node_stack = stack;
1897    }
1898
1899    pub fn move_to_enclosing_bracket(
1900        &mut self,
1901        _: &MoveToEnclosingBracket,
1902        cx: &mut ViewContext<Self>,
1903    ) {
1904        let buffer = self.buffer.read(cx.as_ref());
1905        let mut selections = self.selections(cx.as_ref()).to_vec();
1906        for selection in &mut selections {
1907            let selection_range = selection.offset_range(buffer);
1908            if let Some((open_range, close_range)) =
1909                buffer.enclosing_bracket_ranges(selection_range.clone())
1910            {
1911                let close_range = close_range.to_inclusive();
1912                let destination = if close_range.contains(&selection_range.start)
1913                    && close_range.contains(&selection_range.end)
1914                {
1915                    open_range.end
1916                } else {
1917                    *close_range.start()
1918                };
1919                selection.start = buffer.anchor_before(destination);
1920                selection.end = selection.start.clone();
1921            }
1922        }
1923
1924        self.update_selections(selections, true, cx);
1925    }
1926
1927    fn build_columnar_selection(
1928        &mut self,
1929        display_map: &DisplayMapSnapshot,
1930        row: u32,
1931        columns: &Range<u32>,
1932        reversed: bool,
1933    ) -> Option<Selection> {
1934        let is_empty = columns.start == columns.end;
1935        let line_len = display_map.line_len(row);
1936        if columns.start < line_len || (is_empty && columns.start == line_len) {
1937            let start = DisplayPoint::new(row, columns.start);
1938            let end = DisplayPoint::new(row, cmp::min(columns.end, line_len));
1939            Some(Selection {
1940                id: post_inc(&mut self.next_selection_id),
1941                start: display_map.anchor_before(start, Bias::Left),
1942                end: display_map.anchor_before(end, Bias::Left),
1943                reversed,
1944                goal: SelectionGoal::ColumnRange {
1945                    start: columns.start,
1946                    end: columns.end,
1947                },
1948            })
1949        } else {
1950            None
1951        }
1952    }
1953
1954    pub fn active_selection_sets<'a>(
1955        &'a self,
1956        cx: &'a AppContext,
1957    ) -> impl 'a + Iterator<Item = SelectionSetId> {
1958        self.buffer
1959            .read(cx)
1960            .selection_sets()
1961            .filter(|(_, set)| set.active)
1962            .map(|(set_id, _)| *set_id)
1963    }
1964
1965    pub fn selections_in_range<'a>(
1966        &'a self,
1967        set_id: SelectionSetId,
1968        range: Range<DisplayPoint>,
1969        cx: &'a mut MutableAppContext,
1970    ) -> impl 'a + Iterator<Item = Range<DisplayPoint>> {
1971        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
1972        let buffer = self.buffer.read(cx);
1973        let selections = &buffer.selection_set(set_id).unwrap().selections;
1974        let start = display_map.anchor_before(range.start, Bias::Left);
1975        let start_index = self.selection_insertion_index(selections, &start, cx);
1976        let pending_selection = if set_id.replica_id == self.buffer.read(cx).replica_id() {
1977            self.pending_selection.as_ref().and_then(|s| {
1978                let selection_range = s.display_range(&display_map);
1979                if selection_range.start <= range.end || selection_range.end <= range.end {
1980                    Some(selection_range)
1981                } else {
1982                    None
1983                }
1984            })
1985        } else {
1986            None
1987        };
1988        selections[start_index..]
1989            .iter()
1990            .map(move |s| s.display_range(&display_map))
1991            .take_while(move |r| r.start <= range.end || r.end <= range.end)
1992            .chain(pending_selection)
1993    }
1994
1995    fn selection_insertion_index(
1996        &self,
1997        selections: &[Selection],
1998        start: &Anchor,
1999        cx: &AppContext,
2000    ) -> usize {
2001        let buffer = self.buffer.read(cx);
2002        match selections.binary_search_by(|probe| probe.start.cmp(&start, buffer).unwrap()) {
2003            Ok(index) => index,
2004            Err(index) => {
2005                if index > 0
2006                    && selections[index - 1].end.cmp(&start, buffer).unwrap() == Ordering::Greater
2007                {
2008                    index - 1
2009                } else {
2010                    index
2011                }
2012            }
2013        }
2014    }
2015
2016    fn selections<'a>(&self, cx: &'a AppContext) -> &'a [Selection] {
2017        let buffer = self.buffer.read(cx);
2018        &buffer
2019            .selection_set(self.selection_set_id)
2020            .unwrap()
2021            .selections
2022    }
2023
2024    fn update_selections(
2025        &mut self,
2026        mut selections: Vec<Selection>,
2027        autoscroll: bool,
2028        cx: &mut ViewContext<Self>,
2029    ) {
2030        // Merge overlapping selections.
2031        let buffer = self.buffer.read(cx);
2032        let mut i = 1;
2033        while i < selections.len() {
2034            if selections[i - 1]
2035                .end
2036                .cmp(&selections[i].start, buffer)
2037                .unwrap()
2038                >= Ordering::Equal
2039            {
2040                let removed = selections.remove(i);
2041                if removed.start.cmp(&selections[i - 1].start, buffer).unwrap() < Ordering::Equal {
2042                    selections[i - 1].start = removed.start;
2043                }
2044                if removed.end.cmp(&selections[i - 1].end, buffer).unwrap() > Ordering::Equal {
2045                    selections[i - 1].end = removed.end;
2046                }
2047            } else {
2048                i += 1;
2049            }
2050        }
2051
2052        self.buffer.update(cx, |buffer, cx| {
2053            buffer
2054                .update_selection_set(self.selection_set_id, selections, cx)
2055                .unwrap();
2056        });
2057        self.pause_cursor_blinking(cx);
2058
2059        if autoscroll {
2060            self.autoscroll_requested = true;
2061            cx.notify();
2062        }
2063
2064        self.add_selections_state = None;
2065        self.select_larger_syntax_node_stack.clear();
2066    }
2067
2068    fn start_transaction(&self, cx: &mut ViewContext<Self>) {
2069        self.buffer.update(cx, |buffer, _| {
2070            buffer
2071                .start_transaction(Some(self.selection_set_id))
2072                .unwrap()
2073        });
2074    }
2075
2076    fn end_transaction(&self, cx: &mut ViewContext<Self>) {
2077        self.buffer.update(cx, |buffer, cx| {
2078            buffer
2079                .end_transaction(Some(self.selection_set_id), cx)
2080                .unwrap()
2081        });
2082    }
2083
2084    pub fn page_up(&mut self, _: &PageUp, _: &mut ViewContext<Self>) {
2085        log::info!("BufferView::page_up");
2086    }
2087
2088    pub fn page_down(&mut self, _: &PageDown, _: &mut ViewContext<Self>) {
2089        log::info!("BufferView::page_down");
2090    }
2091
2092    pub fn fold(&mut self, _: &Fold, cx: &mut ViewContext<Self>) {
2093        let mut fold_ranges = Vec::new();
2094
2095        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2096        for selection in self.selections(cx) {
2097            let range = selection.display_range(&display_map).sorted();
2098            let buffer_start_row = range.start.to_buffer_point(&display_map, Bias::Left).row;
2099
2100            for row in (0..=range.end.row()).rev() {
2101                if self.is_line_foldable(&display_map, row) && !display_map.is_line_folded(row) {
2102                    let fold_range = self.foldable_range_for_line(&display_map, row);
2103                    if fold_range.end.row >= buffer_start_row {
2104                        fold_ranges.push(fold_range);
2105                        if row <= range.start.row() {
2106                            break;
2107                        }
2108                    }
2109                }
2110            }
2111        }
2112
2113        self.fold_ranges(fold_ranges, cx);
2114    }
2115
2116    pub fn unfold(&mut self, _: &Unfold, cx: &mut ViewContext<Self>) {
2117        let display_map = self.display_map.update(cx, |map, cx| map.snapshot(cx));
2118        let buffer = self.buffer.read(cx);
2119        let ranges = self
2120            .selections(cx)
2121            .iter()
2122            .map(|s| {
2123                let range = s.display_range(&display_map).sorted();
2124                let mut start = range.start.to_buffer_point(&display_map, Bias::Left);
2125                let mut end = range.end.to_buffer_point(&display_map, Bias::Left);
2126                start.column = 0;
2127                end.column = buffer.line_len(end.row);
2128                start..end
2129            })
2130            .collect::<Vec<_>>();
2131        self.unfold_ranges(ranges, cx);
2132    }
2133
2134    fn is_line_foldable(&self, display_map: &DisplayMapSnapshot, display_row: u32) -> bool {
2135        let max_point = display_map.max_point();
2136        if display_row >= max_point.row() {
2137            false
2138        } else {
2139            let (start_indent, is_blank) = display_map.line_indent(display_row);
2140            if is_blank {
2141                false
2142            } else {
2143                for display_row in display_row + 1..=max_point.row() {
2144                    let (indent, is_blank) = display_map.line_indent(display_row);
2145                    if !is_blank {
2146                        return indent > start_indent;
2147                    }
2148                }
2149                false
2150            }
2151        }
2152    }
2153
2154    fn foldable_range_for_line(
2155        &self,
2156        display_map: &DisplayMapSnapshot,
2157        start_row: u32,
2158    ) -> Range<Point> {
2159        let max_point = display_map.max_point();
2160
2161        let (start_indent, _) = display_map.line_indent(start_row);
2162        let start = DisplayPoint::new(start_row, display_map.line_len(start_row));
2163        let mut end = None;
2164        for row in start_row + 1..=max_point.row() {
2165            let (indent, is_blank) = display_map.line_indent(row);
2166            if !is_blank && indent <= start_indent {
2167                end = Some(DisplayPoint::new(row - 1, display_map.line_len(row - 1)));
2168                break;
2169            }
2170        }
2171
2172        let end = end.unwrap_or(max_point);
2173        return start.to_buffer_point(display_map, Bias::Left)
2174            ..end.to_buffer_point(display_map, Bias::Left);
2175    }
2176
2177    pub fn fold_selected_ranges(&mut self, _: &FoldSelectedRanges, cx: &mut ViewContext<Self>) {
2178        let buffer = self.buffer.read(cx);
2179        let ranges = self
2180            .selections(cx.as_ref())
2181            .iter()
2182            .map(|s| s.point_range(buffer).sorted())
2183            .collect();
2184        self.fold_ranges(ranges, cx);
2185    }
2186
2187    fn fold_ranges<T: ToOffset>(&mut self, ranges: Vec<Range<T>>, cx: &mut ViewContext<Self>) {
2188        if !ranges.is_empty() {
2189            self.display_map.update(cx, |map, cx| map.fold(ranges, cx));
2190            self.autoscroll_requested = true;
2191            cx.notify();
2192        }
2193    }
2194
2195    fn unfold_ranges<T: ToOffset>(&mut self, ranges: Vec<Range<T>>, cx: &mut ViewContext<Self>) {
2196        if !ranges.is_empty() {
2197            self.display_map
2198                .update(cx, |map, cx| map.unfold(ranges, cx));
2199            self.autoscroll_requested = true;
2200            cx.notify();
2201        }
2202    }
2203
2204    pub fn longest_row(&self, cx: &mut MutableAppContext) -> u32 {
2205        self.display_map
2206            .update(cx, |map, cx| map.snapshot(cx))
2207            .longest_row()
2208    }
2209
2210    pub fn max_point(&self, cx: &mut MutableAppContext) -> DisplayPoint {
2211        self.display_map
2212            .update(cx, |map, cx| map.snapshot(cx))
2213            .max_point()
2214    }
2215
2216    pub fn text(&self, cx: &AppContext) -> String {
2217        self.buffer.read(cx).text()
2218    }
2219
2220    pub fn display_text(&self, cx: &mut MutableAppContext) -> String {
2221        self.display_map
2222            .update(cx, |map, cx| map.snapshot(cx))
2223            .text()
2224    }
2225
2226    pub fn font_size(&self) -> f32 {
2227        self.settings.borrow().buffer_font_size
2228    }
2229
2230    pub fn set_wrap_width(&self, width: f32, cx: &mut MutableAppContext) -> bool {
2231        self.display_map
2232            .update(cx, |map, cx| map.set_wrap_width(Some(width), cx))
2233    }
2234
2235    fn next_blink_epoch(&mut self) -> usize {
2236        self.blink_epoch += 1;
2237        self.blink_epoch
2238    }
2239
2240    fn pause_cursor_blinking(&mut self, cx: &mut ViewContext<Self>) {
2241        self.cursors_visible = true;
2242        cx.notify();
2243
2244        let epoch = self.next_blink_epoch();
2245        cx.spawn(|this, mut cx| {
2246            let this = this.downgrade();
2247            async move {
2248                Timer::after(CURSOR_BLINK_INTERVAL).await;
2249                if let Some(this) = cx.read(|cx| this.upgrade(cx)) {
2250                    this.update(&mut cx, |this, cx| this.resume_cursor_blinking(epoch, cx))
2251                }
2252            }
2253        })
2254        .detach();
2255    }
2256
2257    fn resume_cursor_blinking(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
2258        if epoch == self.blink_epoch {
2259            self.blinking_paused = false;
2260            self.blink_cursors(epoch, cx);
2261        }
2262    }
2263
2264    fn blink_cursors(&mut self, epoch: usize, cx: &mut ViewContext<Self>) {
2265        if epoch == self.blink_epoch && self.focused && !self.blinking_paused {
2266            self.cursors_visible = !self.cursors_visible;
2267            cx.notify();
2268
2269            let epoch = self.next_blink_epoch();
2270            cx.spawn(|this, mut cx| {
2271                let this = this.downgrade();
2272                async move {
2273                    Timer::after(CURSOR_BLINK_INTERVAL).await;
2274                    if let Some(this) = cx.read(|cx| this.upgrade(cx)) {
2275                        this.update(&mut cx, |this, cx| this.blink_cursors(epoch, cx));
2276                    }
2277                }
2278            })
2279            .detach();
2280        }
2281    }
2282
2283    pub fn cursors_visible(&self) -> bool {
2284        self.cursors_visible
2285    }
2286
2287    fn on_buffer_changed(&mut self, _: ModelHandle<Buffer>, cx: &mut ViewContext<Self>) {
2288        cx.notify();
2289    }
2290
2291    fn on_buffer_event(
2292        &mut self,
2293        _: ModelHandle<Buffer>,
2294        event: &buffer::Event,
2295        cx: &mut ViewContext<Self>,
2296    ) {
2297        match event {
2298            buffer::Event::Edited => cx.emit(Event::Edited),
2299            buffer::Event::Dirtied => cx.emit(Event::Dirtied),
2300            buffer::Event::Saved => cx.emit(Event::Saved),
2301            buffer::Event::FileHandleChanged => cx.emit(Event::FileHandleChanged),
2302            buffer::Event::Reloaded => cx.emit(Event::FileHandleChanged),
2303            buffer::Event::Reparsed => {}
2304        }
2305    }
2306
2307    fn on_display_map_changed(&mut self, _: ModelHandle<DisplayMap>, cx: &mut ViewContext<Self>) {
2308        cx.notify();
2309    }
2310}
2311
2312impl Snapshot {
2313    pub fn scroll_position(&self) -> Vector2F {
2314        compute_scroll_position(
2315            &self.display_snapshot,
2316            self.scroll_position,
2317            &self.scroll_top_anchor,
2318        )
2319    }
2320
2321    pub fn max_point(&self) -> DisplayPoint {
2322        self.display_snapshot.max_point()
2323    }
2324
2325    pub fn longest_row(&self) -> u32 {
2326        self.display_snapshot.longest_row()
2327    }
2328
2329    pub fn line_len(&self, display_row: u32) -> u32 {
2330        self.display_snapshot.line_len(display_row)
2331    }
2332
2333    pub fn font_ascent(&self, font_cache: &FontCache) -> f32 {
2334        let font_id = font_cache.default_font(self.font_family);
2335        let ascent = font_cache.metric(font_id, |m| m.ascent);
2336        font_cache.scale_metric(ascent, font_id, self.font_size)
2337    }
2338
2339    pub fn font_descent(&self, font_cache: &FontCache) -> f32 {
2340        let font_id = font_cache.default_font(self.font_family);
2341        let descent = font_cache.metric(font_id, |m| m.descent);
2342        font_cache.scale_metric(descent, font_id, self.font_size)
2343    }
2344
2345    pub fn line_height(&self, font_cache: &FontCache) -> f32 {
2346        let font_id = font_cache.default_font(self.font_family);
2347        font_cache.line_height(font_id, self.font_size)
2348    }
2349
2350    pub fn em_width(&self, font_cache: &FontCache) -> f32 {
2351        let font_id = font_cache.default_font(self.font_family);
2352        font_cache.em_width(font_id, self.font_size)
2353    }
2354
2355    // TODO: Can we make this not return a result?
2356    pub fn max_line_number_width(
2357        &self,
2358        font_cache: &FontCache,
2359        layout_cache: &TextLayoutCache,
2360    ) -> Result<f32> {
2361        let font_size = self.font_size;
2362        let font_id = font_cache.select_font(self.font_family, &FontProperties::new())?;
2363        let digit_count = (self.display_snapshot.buffer_row_count() as f32)
2364            .log10()
2365            .floor() as usize
2366            + 1;
2367
2368        Ok(layout_cache
2369            .layout_str(
2370                "1".repeat(digit_count).as_str(),
2371                font_size,
2372                &[(digit_count, font_id, Color::black())],
2373            )
2374            .width())
2375    }
2376
2377    pub fn layout_line_numbers(
2378        &self,
2379        rows: Range<u32>,
2380        active_rows: &BTreeMap<u32, bool>,
2381        font_cache: &FontCache,
2382        layout_cache: &TextLayoutCache,
2383        theme: &Theme,
2384    ) -> Result<Vec<Option<text_layout::Line>>> {
2385        let font_id = font_cache.select_font(self.font_family, &FontProperties::new())?;
2386
2387        let mut layouts = Vec::with_capacity(rows.len());
2388        let mut line_number = String::new();
2389        for (ix, (buffer_row, soft_wrapped)) in self
2390            .display_snapshot
2391            .buffer_rows(rows.start)
2392            .take((rows.end - rows.start) as usize)
2393            .enumerate()
2394        {
2395            let display_row = rows.start + ix as u32;
2396            let color = if active_rows.contains_key(&display_row) {
2397                theme.editor.line_number_active
2398            } else {
2399                theme.editor.line_number
2400            };
2401            if soft_wrapped {
2402                layouts.push(None);
2403            } else {
2404                line_number.clear();
2405                write!(&mut line_number, "{}", buffer_row + 1).unwrap();
2406                layouts.push(Some(layout_cache.layout_str(
2407                    &line_number,
2408                    self.font_size,
2409                    &[(line_number.len(), font_id, color)],
2410                )));
2411            }
2412        }
2413
2414        Ok(layouts)
2415    }
2416
2417    pub fn layout_lines(
2418        &mut self,
2419        mut rows: Range<u32>,
2420        style: &EditorStyle,
2421        font_cache: &FontCache,
2422        layout_cache: &TextLayoutCache,
2423    ) -> Result<Vec<text_layout::Line>> {
2424        rows.end = cmp::min(rows.end, self.display_snapshot.max_point().row() + 1);
2425        if rows.start >= rows.end {
2426            return Ok(Vec::new());
2427        }
2428
2429        // When the editor is empty and unfocused, then show the placeholder.
2430        if self.display_snapshot.is_empty() && !self.is_focused {
2431            let placeholder_lines = self
2432                .placeholder_text
2433                .as_ref()
2434                .map_or("", AsRef::as_ref)
2435                .split('\n')
2436                .skip(rows.start as usize)
2437                .take(rows.len());
2438            let font_id = font_cache
2439                .select_font(self.font_family, &style.placeholder_text.font_properties)?;
2440            return Ok(placeholder_lines
2441                .into_iter()
2442                .map(|line| {
2443                    layout_cache.layout_str(
2444                        line,
2445                        self.font_size,
2446                        &[(line.len(), font_id, style.placeholder_text.color)],
2447                    )
2448                })
2449                .collect());
2450        }
2451
2452        let mut prev_font_properties = FontProperties::new();
2453        let mut prev_font_id = font_cache
2454            .select_font(self.font_family, &prev_font_properties)
2455            .unwrap();
2456
2457        let mut layouts = Vec::with_capacity(rows.len());
2458        let mut line = String::new();
2459        let mut styles = Vec::new();
2460        let mut row = rows.start;
2461        let mut line_exceeded_max_len = false;
2462        let chunks = self
2463            .display_snapshot
2464            .highlighted_chunks_for_rows(rows.clone());
2465
2466        'outer: for (chunk, style_ix) in chunks.chain(Some(("\n", HighlightId::default()))) {
2467            for (ix, mut line_chunk) in chunk.split('\n').enumerate() {
2468                if ix > 0 {
2469                    layouts.push(layout_cache.layout_str(&line, self.font_size, &styles));
2470                    line.clear();
2471                    styles.clear();
2472                    row += 1;
2473                    line_exceeded_max_len = false;
2474                    if row == rows.end {
2475                        break 'outer;
2476                    }
2477                }
2478
2479                if !line_chunk.is_empty() && !line_exceeded_max_len {
2480                    let style = self
2481                        .theme
2482                        .syntax
2483                        .highlight_style(style_ix)
2484                        .unwrap_or(style.text.clone());
2485                    // Avoid a lookup if the font properties match the previous ones.
2486                    let font_id = if style.font_properties == prev_font_properties {
2487                        prev_font_id
2488                    } else {
2489                        font_cache.select_font(self.font_family, &style.font_properties)?
2490                    };
2491
2492                    if line.len() + line_chunk.len() > MAX_LINE_LEN {
2493                        let mut chunk_len = MAX_LINE_LEN - line.len();
2494                        while !line_chunk.is_char_boundary(chunk_len) {
2495                            chunk_len -= 1;
2496                        }
2497                        line_chunk = &line_chunk[..chunk_len];
2498                        line_exceeded_max_len = true;
2499                    }
2500
2501                    line.push_str(line_chunk);
2502                    styles.push((line_chunk.len(), font_id, style.color));
2503                    prev_font_id = font_id;
2504                    prev_font_properties = style.font_properties;
2505                }
2506            }
2507        }
2508
2509        Ok(layouts)
2510    }
2511
2512    pub fn layout_line(
2513        &self,
2514        row: u32,
2515        font_cache: &FontCache,
2516        layout_cache: &TextLayoutCache,
2517    ) -> Result<text_layout::Line> {
2518        let font_id = font_cache.select_font(self.font_family, &FontProperties::new())?;
2519
2520        let mut line = self.display_snapshot.line(row);
2521
2522        if line.len() > MAX_LINE_LEN {
2523            let mut len = MAX_LINE_LEN;
2524            while !line.is_char_boundary(len) {
2525                len -= 1;
2526            }
2527            line.truncate(len);
2528        }
2529
2530        Ok(layout_cache.layout_str(
2531            &line,
2532            self.font_size,
2533            &[(
2534                self.display_snapshot.line_len(row) as usize,
2535                font_id,
2536                Color::black(),
2537            )],
2538        ))
2539    }
2540
2541    pub fn prev_row_boundary(&self, point: DisplayPoint) -> (DisplayPoint, Point) {
2542        self.display_snapshot.prev_row_boundary(point)
2543    }
2544
2545    pub fn next_row_boundary(&self, point: DisplayPoint) -> (DisplayPoint, Point) {
2546        self.display_snapshot.next_row_boundary(point)
2547    }
2548}
2549
2550fn compute_scroll_position(
2551    snapshot: &DisplayMapSnapshot,
2552    mut scroll_position: Vector2F,
2553    scroll_top_anchor: &Anchor,
2554) -> Vector2F {
2555    let scroll_top = scroll_top_anchor
2556        .to_display_point(snapshot, Bias::Left)
2557        .row() as f32;
2558    scroll_position.set_y(scroll_top + scroll_position.y());
2559    scroll_position
2560}
2561
2562pub enum Event {
2563    Activate,
2564    Edited,
2565    Blurred,
2566    Dirtied,
2567    Saved,
2568    FileHandleChanged,
2569}
2570
2571impl Entity for Editor {
2572    type Event = Event;
2573
2574    fn release(&mut self, cx: &mut MutableAppContext) {
2575        self.buffer.update(cx, |buffer, cx| {
2576            buffer
2577                .remove_selection_set(self.selection_set_id, cx)
2578                .unwrap();
2579        });
2580    }
2581}
2582
2583impl View for Editor {
2584    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
2585        let style = self
2586            .build_style
2587            .as_ref()
2588            .map_or(Default::default(), |build| (build.borrow_mut())(cx));
2589        EditorElement::new(self.handle.clone(), style).boxed()
2590    }
2591
2592    fn ui_name() -> &'static str {
2593        "BufferView"
2594    }
2595
2596    fn on_focus(&mut self, cx: &mut ViewContext<Self>) {
2597        self.focused = true;
2598        self.blink_cursors(self.blink_epoch, cx);
2599        self.buffer.update(cx, |buffer, cx| {
2600            buffer
2601                .set_active_selection_set(Some(self.selection_set_id), cx)
2602                .unwrap();
2603        });
2604    }
2605
2606    fn on_blur(&mut self, cx: &mut ViewContext<Self>) {
2607        self.focused = false;
2608        self.cursors_visible = false;
2609        self.buffer.update(cx, |buffer, cx| {
2610            buffer.set_active_selection_set(None, cx).unwrap();
2611        });
2612        cx.emit(Event::Blurred);
2613        cx.notify();
2614    }
2615}
2616
2617impl workspace::Item for Buffer {
2618    type View = Editor;
2619
2620    fn file(&self) -> Option<&File> {
2621        self.file()
2622    }
2623
2624    fn build_view(
2625        handle: ModelHandle<Self>,
2626        settings: watch::Receiver<Settings>,
2627        cx: &mut ViewContext<Self::View>,
2628    ) -> Self::View {
2629        Editor::for_buffer(handle, settings.clone(), cx)
2630            .with_style(move |_| settings.borrow().theme.editor.clone())
2631    }
2632}
2633
2634impl workspace::ItemView for Editor {
2635    fn should_activate_item_on_event(event: &Self::Event) -> bool {
2636        matches!(event, Event::Activate)
2637    }
2638
2639    fn should_update_tab_on_event(event: &Self::Event) -> bool {
2640        matches!(
2641            event,
2642            Event::Saved | Event::Dirtied | Event::FileHandleChanged
2643        )
2644    }
2645
2646    fn title(&self, cx: &AppContext) -> std::string::String {
2647        let filename = self
2648            .buffer
2649            .read(cx)
2650            .file()
2651            .and_then(|file| file.file_name(cx));
2652        if let Some(name) = filename {
2653            name.to_string_lossy().into()
2654        } else {
2655            "untitled".into()
2656        }
2657    }
2658
2659    fn entry_id(&self, cx: &AppContext) -> Option<(usize, Arc<Path>)> {
2660        self.buffer.read(cx).file().map(|file| file.entry_id())
2661    }
2662
2663    fn clone_on_split(&self, cx: &mut ViewContext<Self>) -> Option<Self>
2664    where
2665        Self: Sized,
2666    {
2667        let mut clone = Editor::for_buffer(self.buffer.clone(), self.settings.clone(), cx);
2668        clone.scroll_position = self.scroll_position;
2669        clone.scroll_top_anchor = self.scroll_top_anchor.clone();
2670        clone.build_style = self.build_style.clone();
2671        Some(clone)
2672    }
2673
2674    fn save(&mut self, cx: &mut ViewContext<Self>) -> Result<Task<Result<()>>> {
2675        let save = self.buffer.update(cx, |b, cx| b.save(cx))?;
2676        Ok(cx.spawn(|_, _| async move {
2677            save.await?;
2678            Ok(())
2679        }))
2680    }
2681
2682    fn save_as(
2683        &mut self,
2684        worktree: &ModelHandle<Worktree>,
2685        path: &Path,
2686        cx: &mut ViewContext<Self>,
2687    ) -> Task<Result<()>> {
2688        self.buffer
2689            .update(cx, |b, cx| b.save_as(worktree, path, cx))
2690    }
2691
2692    fn is_dirty(&self, cx: &AppContext) -> bool {
2693        self.buffer.read(cx).is_dirty()
2694    }
2695
2696    fn has_conflict(&self, cx: &AppContext) -> bool {
2697        self.buffer.read(cx).has_conflict()
2698    }
2699}
2700
2701#[cfg(test)]
2702mod tests {
2703    use super::*;
2704    use crate::{editor::Point, language::LanguageRegistry, settings, test::sample_text};
2705    use buffer::History;
2706    use unindent::Unindent;
2707
2708    #[gpui::test]
2709    fn test_selection_with_mouse(cx: &mut gpui::MutableAppContext) {
2710        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
2711        let settings = settings::test(&cx).1;
2712        let (_, editor) = cx.add_window(Default::default(), |cx| {
2713            Editor::for_buffer(buffer, settings, cx)
2714        });
2715
2716        editor.update(cx, |view, cx| {
2717            view.begin_selection(DisplayPoint::new(2, 2), false, cx);
2718        });
2719
2720        assert_eq!(
2721            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2722            [DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2)]
2723        );
2724
2725        editor.update(cx, |view, cx| {
2726            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
2727        });
2728
2729        assert_eq!(
2730            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2731            [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
2732        );
2733
2734        editor.update(cx, |view, cx| {
2735            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
2736        });
2737
2738        assert_eq!(
2739            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2740            [DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1)]
2741        );
2742
2743        editor.update(cx, |view, cx| {
2744            view.end_selection(cx);
2745            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
2746        });
2747
2748        assert_eq!(
2749            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2750            [DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1)]
2751        );
2752
2753        editor.update(cx, |view, cx| {
2754            view.begin_selection(DisplayPoint::new(3, 3), true, cx);
2755            view.update_selection(DisplayPoint::new(0, 0), Vector2F::zero(), cx);
2756        });
2757
2758        assert_eq!(
2759            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2760            [
2761                DisplayPoint::new(2, 2)..DisplayPoint::new(1, 1),
2762                DisplayPoint::new(3, 3)..DisplayPoint::new(0, 0)
2763            ]
2764        );
2765
2766        editor.update(cx, |view, cx| {
2767            view.end_selection(cx);
2768        });
2769
2770        assert_eq!(
2771            editor.update(cx, |view, cx| view.selection_ranges(cx)),
2772            [DisplayPoint::new(3, 3)..DisplayPoint::new(0, 0)]
2773        );
2774    }
2775
2776    #[gpui::test]
2777    fn test_canceling_pending_selection(cx: &mut gpui::MutableAppContext) {
2778        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
2779        let settings = settings::test(&cx).1;
2780        let (_, view) = cx.add_window(Default::default(), |cx| {
2781            Editor::for_buffer(buffer, settings, cx)
2782        });
2783
2784        view.update(cx, |view, cx| {
2785            view.begin_selection(DisplayPoint::new(2, 2), false, cx);
2786            assert_eq!(
2787                view.selection_ranges(cx),
2788                [DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2)]
2789            );
2790        });
2791
2792        view.update(cx, |view, cx| {
2793            view.update_selection(DisplayPoint::new(3, 3), Vector2F::zero(), cx);
2794            assert_eq!(
2795                view.selection_ranges(cx),
2796                [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
2797            );
2798        });
2799
2800        view.update(cx, |view, cx| {
2801            view.cancel(&Cancel, cx);
2802            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
2803            assert_eq!(
2804                view.selection_ranges(cx),
2805                [DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3)]
2806            );
2807        });
2808    }
2809
2810    #[gpui::test]
2811    fn test_cancel(cx: &mut gpui::MutableAppContext) {
2812        let buffer = cx.add_model(|cx| Buffer::new(0, "aaaaaa\nbbbbbb\ncccccc\ndddddd\n", cx));
2813        let settings = settings::test(&cx).1;
2814        let (_, view) = cx.add_window(Default::default(), |cx| {
2815            Editor::for_buffer(buffer, settings, cx)
2816        });
2817
2818        view.update(cx, |view, cx| {
2819            view.begin_selection(DisplayPoint::new(3, 4), false, cx);
2820            view.update_selection(DisplayPoint::new(1, 1), Vector2F::zero(), cx);
2821            view.end_selection(cx);
2822
2823            view.begin_selection(DisplayPoint::new(0, 1), true, cx);
2824            view.update_selection(DisplayPoint::new(0, 3), Vector2F::zero(), cx);
2825            view.end_selection(cx);
2826            assert_eq!(
2827                view.selection_ranges(cx),
2828                [
2829                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
2830                    DisplayPoint::new(3, 4)..DisplayPoint::new(1, 1),
2831                ]
2832            );
2833        });
2834
2835        view.update(cx, |view, cx| {
2836            view.cancel(&Cancel, cx);
2837            assert_eq!(
2838                view.selection_ranges(cx),
2839                [DisplayPoint::new(3, 4)..DisplayPoint::new(1, 1)]
2840            );
2841        });
2842
2843        view.update(cx, |view, cx| {
2844            view.cancel(&Cancel, cx);
2845            assert_eq!(
2846                view.selection_ranges(cx),
2847                [DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1)]
2848            );
2849        });
2850    }
2851
2852    #[gpui::test]
2853    fn test_layout_line_numbers(cx: &mut gpui::MutableAppContext) {
2854        let layout_cache = TextLayoutCache::new(cx.platform().fonts());
2855        let font_cache = cx.font_cache().clone();
2856
2857        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 6), cx));
2858
2859        let settings = settings::test(&cx).1;
2860        let (_, editor) = cx.add_window(Default::default(), |cx| {
2861            Editor::for_buffer(buffer.clone(), settings.clone(), cx)
2862        });
2863
2864        let layouts = editor.update(cx, |editor, cx| {
2865            editor
2866                .snapshot(cx)
2867                .layout_line_numbers(
2868                    0..6,
2869                    &Default::default(),
2870                    &font_cache,
2871                    &layout_cache,
2872                    &settings.borrow().theme,
2873                )
2874                .unwrap()
2875        });
2876        assert_eq!(layouts.len(), 6);
2877    }
2878
2879    #[gpui::test]
2880    fn test_fold(cx: &mut gpui::MutableAppContext) {
2881        let buffer = cx.add_model(|cx| {
2882            Buffer::new(
2883                0,
2884                "
2885                    impl Foo {
2886                        // Hello!
2887
2888                        fn a() {
2889                            1
2890                        }
2891
2892                        fn b() {
2893                            2
2894                        }
2895
2896                        fn c() {
2897                            3
2898                        }
2899                    }
2900                "
2901                .unindent(),
2902                cx,
2903            )
2904        });
2905        let settings = settings::test(&cx).1;
2906        let (_, view) = cx.add_window(Default::default(), |cx| {
2907            Editor::for_buffer(buffer.clone(), settings, cx)
2908        });
2909
2910        view.update(cx, |view, cx| {
2911            view.select_display_ranges(&[DisplayPoint::new(8, 0)..DisplayPoint::new(12, 0)], cx)
2912                .unwrap();
2913            view.fold(&Fold, cx);
2914            assert_eq!(
2915                view.display_text(cx),
2916                "
2917                    impl Foo {
2918                        // Hello!
2919
2920                        fn a() {
2921                            1
2922                        }
2923
2924                        fn b() {…
2925                        }
2926
2927                        fn c() {…
2928                        }
2929                    }
2930                "
2931                .unindent(),
2932            );
2933
2934            view.fold(&Fold, cx);
2935            assert_eq!(
2936                view.display_text(cx),
2937                "
2938                    impl Foo {…
2939                    }
2940                "
2941                .unindent(),
2942            );
2943
2944            view.unfold(&Unfold, cx);
2945            assert_eq!(
2946                view.display_text(cx),
2947                "
2948                    impl Foo {
2949                        // Hello!
2950
2951                        fn a() {
2952                            1
2953                        }
2954
2955                        fn b() {…
2956                        }
2957
2958                        fn c() {…
2959                        }
2960                    }
2961                "
2962                .unindent(),
2963            );
2964
2965            view.unfold(&Unfold, cx);
2966            assert_eq!(view.display_text(cx), buffer.read(cx).text());
2967        });
2968    }
2969
2970    #[gpui::test]
2971    fn test_move_cursor(cx: &mut gpui::MutableAppContext) {
2972        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 6), cx));
2973        let settings = settings::test(&cx).1;
2974        let (_, view) = cx.add_window(Default::default(), |cx| {
2975            Editor::for_buffer(buffer.clone(), settings, cx)
2976        });
2977
2978        buffer.update(cx, |buffer, cx| {
2979            buffer.edit(
2980                vec![
2981                    Point::new(1, 0)..Point::new(1, 0),
2982                    Point::new(1, 1)..Point::new(1, 1),
2983                ],
2984                "\t",
2985                cx,
2986            );
2987        });
2988
2989        view.update(cx, |view, cx| {
2990            assert_eq!(
2991                view.selection_ranges(cx),
2992                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
2993            );
2994
2995            view.move_down(&MoveDown, cx);
2996            assert_eq!(
2997                view.selection_ranges(cx),
2998                &[DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0)]
2999            );
3000
3001            view.move_right(&MoveRight, cx);
3002            assert_eq!(
3003                view.selection_ranges(cx),
3004                &[DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4)]
3005            );
3006
3007            view.move_left(&MoveLeft, cx);
3008            assert_eq!(
3009                view.selection_ranges(cx),
3010                &[DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0)]
3011            );
3012
3013            view.move_up(&MoveUp, cx);
3014            assert_eq!(
3015                view.selection_ranges(cx),
3016                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
3017            );
3018
3019            view.move_to_end(&MoveToEnd, cx);
3020            assert_eq!(
3021                view.selection_ranges(cx),
3022                &[DisplayPoint::new(5, 6)..DisplayPoint::new(5, 6)]
3023            );
3024
3025            view.move_to_beginning(&MoveToBeginning, cx);
3026            assert_eq!(
3027                view.selection_ranges(cx),
3028                &[DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0)]
3029            );
3030
3031            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 2)], cx)
3032                .unwrap();
3033            view.select_to_beginning(&SelectToBeginning, cx);
3034            assert_eq!(
3035                view.selection_ranges(cx),
3036                &[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 0)]
3037            );
3038
3039            view.select_to_end(&SelectToEnd, cx);
3040            assert_eq!(
3041                view.selection_ranges(cx),
3042                &[DisplayPoint::new(0, 1)..DisplayPoint::new(5, 6)]
3043            );
3044        });
3045    }
3046
3047    #[gpui::test]
3048    fn test_move_cursor_multibyte(cx: &mut gpui::MutableAppContext) {
3049        let buffer = cx.add_model(|cx| Buffer::new(0, "ⓐⓑⓒⓓⓔ\nabcde\nαβγδε\n", cx));
3050        let settings = settings::test(&cx).1;
3051        let (_, view) = cx.add_window(Default::default(), |cx| {
3052            Editor::for_buffer(buffer.clone(), settings, cx)
3053        });
3054
3055        assert_eq!('ⓐ'.len_utf8(), 3);
3056        assert_eq!('α'.len_utf8(), 2);
3057
3058        view.update(cx, |view, cx| {
3059            view.fold_ranges(
3060                vec![
3061                    Point::new(0, 6)..Point::new(0, 12),
3062                    Point::new(1, 2)..Point::new(1, 4),
3063                    Point::new(2, 4)..Point::new(2, 8),
3064                ],
3065                cx,
3066            );
3067            assert_eq!(view.display_text(cx), "ⓐⓑ…ⓔ\nab…e\nαβ…ε\n");
3068
3069            view.move_right(&MoveRight, cx);
3070            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "".len())]);
3071            view.move_right(&MoveRight, cx);
3072            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ".len())]);
3073            view.move_right(&MoveRight, cx);
3074            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…".len())]);
3075
3076            view.move_down(&MoveDown, cx);
3077            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab…".len())]);
3078            view.move_left(&MoveLeft, cx);
3079            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab".len())]);
3080            view.move_left(&MoveLeft, cx);
3081            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "a".len())]);
3082
3083            view.move_down(&MoveDown, cx);
3084            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "α".len())]);
3085            view.move_right(&MoveRight, cx);
3086            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ".len())]);
3087            view.move_right(&MoveRight, cx);
3088            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ…".len())]);
3089            view.move_right(&MoveRight, cx);
3090            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβ…ε".len())]);
3091
3092            view.move_up(&MoveUp, cx);
3093            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "ab…e".len())]);
3094            view.move_up(&MoveUp, cx);
3095            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…ⓔ".len())]);
3096            view.move_left(&MoveLeft, cx);
3097            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ…".len())]);
3098            view.move_left(&MoveLeft, cx);
3099            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "ⓐⓑ".len())]);
3100            view.move_left(&MoveLeft, cx);
3101            assert_eq!(view.selection_ranges(cx), &[empty_range(0, "".len())]);
3102        });
3103    }
3104
3105    #[gpui::test]
3106    fn test_move_cursor_different_line_lengths(cx: &mut gpui::MutableAppContext) {
3107        let buffer = cx.add_model(|cx| Buffer::new(0, "ⓐⓑⓒⓓⓔ\nabcd\nαβγ\nabcd\nⓐⓑⓒⓓⓔ\n", cx));
3108        let settings = settings::test(&cx).1;
3109        let (_, view) = cx.add_window(Default::default(), |cx| {
3110            Editor::for_buffer(buffer.clone(), settings, cx)
3111        });
3112        view.update(cx, |view, cx| {
3113            view.select_display_ranges(&[empty_range(0, "ⓐⓑⓒⓓⓔ".len())], cx)
3114                .unwrap();
3115
3116            view.move_down(&MoveDown, cx);
3117            assert_eq!(view.selection_ranges(cx), &[empty_range(1, "abcd".len())]);
3118
3119            view.move_down(&MoveDown, cx);
3120            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβγ".len())]);
3121
3122            view.move_down(&MoveDown, cx);
3123            assert_eq!(view.selection_ranges(cx), &[empty_range(3, "abcd".len())]);
3124
3125            view.move_down(&MoveDown, cx);
3126            assert_eq!(view.selection_ranges(cx), &[empty_range(4, "ⓐⓑⓒⓓⓔ".len())]);
3127
3128            view.move_up(&MoveUp, cx);
3129            assert_eq!(view.selection_ranges(cx), &[empty_range(3, "abcd".len())]);
3130
3131            view.move_up(&MoveUp, cx);
3132            assert_eq!(view.selection_ranges(cx), &[empty_range(2, "αβγ".len())]);
3133        });
3134    }
3135
3136    #[gpui::test]
3137    fn test_beginning_end_of_line(cx: &mut gpui::MutableAppContext) {
3138        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\n  def", cx));
3139        let settings = settings::test(&cx).1;
3140        let (_, view) = cx.add_window(Default::default(), |cx| {
3141            Editor::for_buffer(buffer, settings, cx)
3142        });
3143        view.update(cx, |view, cx| {
3144            view.select_display_ranges(
3145                &[
3146                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3147                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4),
3148                ],
3149                cx,
3150            )
3151            .unwrap();
3152        });
3153
3154        view.update(cx, |view, cx| {
3155            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3156            assert_eq!(
3157                view.selection_ranges(cx),
3158                &[
3159                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3160                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3161                ]
3162            );
3163        });
3164
3165        view.update(cx, |view, cx| {
3166            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3167            assert_eq!(
3168                view.selection_ranges(cx),
3169                &[
3170                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3171                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3172                ]
3173            );
3174        });
3175
3176        view.update(cx, |view, cx| {
3177            view.move_to_beginning_of_line(&MoveToBeginningOfLine, cx);
3178            assert_eq!(
3179                view.selection_ranges(cx),
3180                &[
3181                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3182                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3183                ]
3184            );
3185        });
3186
3187        view.update(cx, |view, cx| {
3188            view.move_to_end_of_line(&MoveToEndOfLine, cx);
3189            assert_eq!(
3190                view.selection_ranges(cx),
3191                &[
3192                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3193                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
3194                ]
3195            );
3196        });
3197
3198        // Moving to the end of line again is a no-op.
3199        view.update(cx, |view, cx| {
3200            view.move_to_end_of_line(&MoveToEndOfLine, cx);
3201            assert_eq!(
3202                view.selection_ranges(cx),
3203                &[
3204                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3205                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
3206                ]
3207            );
3208        });
3209
3210        view.update(cx, |view, cx| {
3211            view.move_left(&MoveLeft, cx);
3212            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3213            assert_eq!(
3214                view.selection_ranges(cx),
3215                &[
3216                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3217                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 2),
3218                ]
3219            );
3220        });
3221
3222        view.update(cx, |view, cx| {
3223            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3224            assert_eq!(
3225                view.selection_ranges(cx),
3226                &[
3227                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3228                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 0),
3229                ]
3230            );
3231        });
3232
3233        view.update(cx, |view, cx| {
3234            view.select_to_beginning_of_line(&SelectToBeginningOfLine(true), cx);
3235            assert_eq!(
3236                view.selection_ranges(cx),
3237                &[
3238                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 0),
3239                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 2),
3240                ]
3241            );
3242        });
3243
3244        view.update(cx, |view, cx| {
3245            view.select_to_end_of_line(&SelectToEndOfLine, cx);
3246            assert_eq!(
3247                view.selection_ranges(cx),
3248                &[
3249                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 3),
3250                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 5),
3251                ]
3252            );
3253        });
3254
3255        view.update(cx, |view, cx| {
3256            view.delete_to_end_of_line(&DeleteToEndOfLine, cx);
3257            assert_eq!(view.display_text(cx), "ab\n  de");
3258            assert_eq!(
3259                view.selection_ranges(cx),
3260                &[
3261                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3262                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 4),
3263                ]
3264            );
3265        });
3266
3267        view.update(cx, |view, cx| {
3268            view.delete_to_beginning_of_line(&DeleteToBeginningOfLine, cx);
3269            assert_eq!(view.display_text(cx), "\n");
3270            assert_eq!(
3271                view.selection_ranges(cx),
3272                &[
3273                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3274                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3275                ]
3276            );
3277        });
3278    }
3279
3280    #[gpui::test]
3281    fn test_prev_next_word_boundary(cx: &mut gpui::MutableAppContext) {
3282        let buffer =
3283            cx.add_model(|cx| Buffer::new(0, "use std::str::{foo, bar}\n\n  {baz.qux()}", cx));
3284        let settings = settings::test(&cx).1;
3285        let (_, view) = cx.add_window(Default::default(), |cx| {
3286            Editor::for_buffer(buffer, settings, cx)
3287        });
3288        view.update(cx, |view, cx| {
3289            view.select_display_ranges(
3290                &[
3291                    DisplayPoint::new(0, 11)..DisplayPoint::new(0, 11),
3292                    DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4),
3293                ],
3294                cx,
3295            )
3296            .unwrap();
3297        });
3298
3299        view.update(cx, |view, cx| {
3300            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3301            assert_eq!(
3302                view.selection_ranges(cx),
3303                &[
3304                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 9),
3305                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 3),
3306                ]
3307            );
3308        });
3309
3310        view.update(cx, |view, cx| {
3311            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3312            assert_eq!(
3313                view.selection_ranges(cx),
3314                &[
3315                    DisplayPoint::new(0, 7)..DisplayPoint::new(0, 7),
3316                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2),
3317                ]
3318            );
3319        });
3320
3321        view.update(cx, |view, cx| {
3322            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3323            assert_eq!(
3324                view.selection_ranges(cx),
3325                &[
3326                    DisplayPoint::new(0, 4)..DisplayPoint::new(0, 4),
3327                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 0),
3328                ]
3329            );
3330        });
3331
3332        view.update(cx, |view, cx| {
3333            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3334            assert_eq!(
3335                view.selection_ranges(cx),
3336                &[
3337                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3338                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3339                ]
3340            );
3341        });
3342
3343        view.update(cx, |view, cx| {
3344            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3345            assert_eq!(
3346                view.selection_ranges(cx),
3347                &[
3348                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3349                    DisplayPoint::new(0, 24)..DisplayPoint::new(0, 24),
3350                ]
3351            );
3352        });
3353
3354        view.update(cx, |view, cx| {
3355            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3356            assert_eq!(
3357                view.selection_ranges(cx),
3358                &[
3359                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3360                    DisplayPoint::new(0, 23)..DisplayPoint::new(0, 23),
3361                ]
3362            );
3363        });
3364
3365        view.update(cx, |view, cx| {
3366            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3367            assert_eq!(
3368                view.selection_ranges(cx),
3369                &[
3370                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
3371                    DisplayPoint::new(0, 24)..DisplayPoint::new(0, 24),
3372                ]
3373            );
3374        });
3375
3376        view.update(cx, |view, cx| {
3377            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3378            assert_eq!(
3379                view.selection_ranges(cx),
3380                &[
3381                    DisplayPoint::new(0, 4)..DisplayPoint::new(0, 4),
3382                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3383                ]
3384            );
3385        });
3386
3387        view.update(cx, |view, cx| {
3388            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3389            assert_eq!(
3390                view.selection_ranges(cx),
3391                &[
3392                    DisplayPoint::new(0, 7)..DisplayPoint::new(0, 7),
3393                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 0),
3394                ]
3395            );
3396        });
3397
3398        view.update(cx, |view, cx| {
3399            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3400            assert_eq!(
3401                view.selection_ranges(cx),
3402                &[
3403                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 9),
3404                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2),
3405                ]
3406            );
3407        });
3408
3409        view.update(cx, |view, cx| {
3410            view.move_right(&MoveRight, cx);
3411            view.select_to_previous_word_boundary(&SelectToPreviousWordBoundary, cx);
3412            assert_eq!(
3413                view.selection_ranges(cx),
3414                &[
3415                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 9),
3416                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 2),
3417                ]
3418            );
3419        });
3420
3421        view.update(cx, |view, cx| {
3422            view.select_to_previous_word_boundary(&SelectToPreviousWordBoundary, cx);
3423            assert_eq!(
3424                view.selection_ranges(cx),
3425                &[
3426                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 7),
3427                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 0),
3428                ]
3429            );
3430        });
3431
3432        view.update(cx, |view, cx| {
3433            view.select_to_next_word_boundary(&SelectToNextWordBoundary, cx);
3434            assert_eq!(
3435                view.selection_ranges(cx),
3436                &[
3437                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 9),
3438                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 2),
3439                ]
3440            );
3441        });
3442
3443        view.update(cx, |view, cx| {
3444            view.delete_to_next_word_boundary(&DeleteToNextWordBoundary, cx);
3445            assert_eq!(
3446                view.display_text(cx),
3447                "use std::s::{foo, bar}\n\n  {az.qux()}"
3448            );
3449            assert_eq!(
3450                view.selection_ranges(cx),
3451                &[
3452                    DisplayPoint::new(0, 10)..DisplayPoint::new(0, 10),
3453                    DisplayPoint::new(2, 3)..DisplayPoint::new(2, 3),
3454                ]
3455            );
3456        });
3457
3458        view.update(cx, |view, cx| {
3459            view.delete_to_previous_word_boundary(&DeleteToPreviousWordBoundary, cx);
3460            assert_eq!(
3461                view.display_text(cx),
3462                "use std::::{foo, bar}\n\n  az.qux()}"
3463            );
3464            assert_eq!(
3465                view.selection_ranges(cx),
3466                &[
3467                    DisplayPoint::new(0, 9)..DisplayPoint::new(0, 9),
3468                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 2),
3469                ]
3470            );
3471        });
3472    }
3473
3474    #[gpui::test]
3475    fn test_prev_next_word_bounds_with_soft_wrap(cx: &mut gpui::MutableAppContext) {
3476        let buffer =
3477            cx.add_model(|cx| Buffer::new(0, "use one::{\n    two::three::four::five\n};", cx));
3478        let settings = settings::test(&cx).1;
3479        let (_, view) = cx.add_window(Default::default(), |cx| {
3480            Editor::for_buffer(buffer, settings, cx)
3481        });
3482
3483        view.update(cx, |view, cx| {
3484            view.set_wrap_width(140., cx);
3485            assert_eq!(
3486                view.display_text(cx),
3487                "use one::{\n    two::three::\n    four::five\n};"
3488            );
3489
3490            view.select_display_ranges(&[DisplayPoint::new(1, 7)..DisplayPoint::new(1, 7)], cx)
3491                .unwrap();
3492
3493            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3494            assert_eq!(
3495                view.selection_ranges(cx),
3496                &[DisplayPoint::new(1, 9)..DisplayPoint::new(1, 9)]
3497            );
3498
3499            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3500            assert_eq!(
3501                view.selection_ranges(cx),
3502                &[DisplayPoint::new(1, 14)..DisplayPoint::new(1, 14)]
3503            );
3504
3505            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3506            assert_eq!(
3507                view.selection_ranges(cx),
3508                &[DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4)]
3509            );
3510
3511            view.move_to_next_word_boundary(&MoveToNextWordBoundary, cx);
3512            assert_eq!(
3513                view.selection_ranges(cx),
3514                &[DisplayPoint::new(2, 8)..DisplayPoint::new(2, 8)]
3515            );
3516
3517            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3518            assert_eq!(
3519                view.selection_ranges(cx),
3520                &[DisplayPoint::new(2, 4)..DisplayPoint::new(2, 4)]
3521            );
3522
3523            view.move_to_previous_word_boundary(&MoveToPreviousWordBoundary, cx);
3524            assert_eq!(
3525                view.selection_ranges(cx),
3526                &[DisplayPoint::new(1, 15)..DisplayPoint::new(1, 15)]
3527            );
3528        });
3529    }
3530
3531    #[gpui::test]
3532    fn test_backspace(cx: &mut gpui::MutableAppContext) {
3533        let buffer = cx.add_model(|cx| {
3534            Buffer::new(
3535                0,
3536                "one two three\nfour five six\nseven eight nine\nten\n",
3537                cx,
3538            )
3539        });
3540        let settings = settings::test(&cx).1;
3541        let (_, view) = cx.add_window(Default::default(), |cx| {
3542            Editor::for_buffer(buffer.clone(), settings, cx)
3543        });
3544
3545        view.update(cx, |view, cx| {
3546            view.select_display_ranges(
3547                &[
3548                    // an empty selection - the preceding character is deleted
3549                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3550                    // one character selected - it is deleted
3551                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
3552                    // a line suffix selected - it is deleted
3553                    DisplayPoint::new(2, 6)..DisplayPoint::new(3, 0),
3554                ],
3555                cx,
3556            )
3557            .unwrap();
3558            view.backspace(&Backspace, cx);
3559        });
3560
3561        assert_eq!(
3562            buffer.read(cx).text(),
3563            "oe two three\nfou five six\nseven ten\n"
3564        );
3565    }
3566
3567    #[gpui::test]
3568    fn test_delete(cx: &mut gpui::MutableAppContext) {
3569        let buffer = cx.add_model(|cx| {
3570            Buffer::new(
3571                0,
3572                "one two three\nfour five six\nseven eight nine\nten\n",
3573                cx,
3574            )
3575        });
3576        let settings = settings::test(&cx).1;
3577        let (_, view) = cx.add_window(Default::default(), |cx| {
3578            Editor::for_buffer(buffer.clone(), settings, cx)
3579        });
3580
3581        view.update(cx, |view, cx| {
3582            view.select_display_ranges(
3583                &[
3584                    // an empty selection - the following character is deleted
3585                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3586                    // one character selected - it is deleted
3587                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
3588                    // a line suffix selected - it is deleted
3589                    DisplayPoint::new(2, 6)..DisplayPoint::new(3, 0),
3590                ],
3591                cx,
3592            )
3593            .unwrap();
3594            view.delete(&Delete, cx);
3595        });
3596
3597        assert_eq!(
3598            buffer.read(cx).text(),
3599            "on two three\nfou five six\nseven ten\n"
3600        );
3601    }
3602
3603    #[gpui::test]
3604    fn test_delete_line(cx: &mut gpui::MutableAppContext) {
3605        let settings = settings::test(&cx).1;
3606        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3607        let (_, view) = cx.add_window(Default::default(), |cx| {
3608            Editor::for_buffer(buffer, settings, cx)
3609        });
3610        view.update(cx, |view, cx| {
3611            view.select_display_ranges(
3612                &[
3613                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3614                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 1),
3615                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3616                ],
3617                cx,
3618            )
3619            .unwrap();
3620            view.delete_line(&DeleteLine, cx);
3621            assert_eq!(view.display_text(cx), "ghi");
3622            assert_eq!(
3623                view.selection_ranges(cx),
3624                vec![
3625                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 0),
3626                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)
3627                ]
3628            );
3629        });
3630
3631        let settings = settings::test(&cx).1;
3632        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3633        let (_, view) = cx.add_window(Default::default(), |cx| {
3634            Editor::for_buffer(buffer, settings, cx)
3635        });
3636        view.update(cx, |view, cx| {
3637            view.select_display_ranges(&[DisplayPoint::new(2, 0)..DisplayPoint::new(0, 1)], cx)
3638                .unwrap();
3639            view.delete_line(&DeleteLine, cx);
3640            assert_eq!(view.display_text(cx), "ghi\n");
3641            assert_eq!(
3642                view.selection_ranges(cx),
3643                vec![DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)]
3644            );
3645        });
3646    }
3647
3648    #[gpui::test]
3649    fn test_duplicate_line(cx: &mut gpui::MutableAppContext) {
3650        let settings = settings::test(&cx).1;
3651        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3652        let (_, view) = cx.add_window(Default::default(), |cx| {
3653            Editor::for_buffer(buffer, settings, cx)
3654        });
3655        view.update(cx, |view, cx| {
3656            view.select_display_ranges(
3657                &[
3658                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
3659                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3660                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3661                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3662                ],
3663                cx,
3664            )
3665            .unwrap();
3666            view.duplicate_line(&DuplicateLine, cx);
3667            assert_eq!(view.display_text(cx), "abc\nabc\ndef\ndef\nghi\n\n");
3668            assert_eq!(
3669                view.selection_ranges(cx),
3670                vec![
3671                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 1),
3672                    DisplayPoint::new(1, 2)..DisplayPoint::new(1, 2),
3673                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3674                    DisplayPoint::new(6, 0)..DisplayPoint::new(6, 0),
3675                ]
3676            );
3677        });
3678
3679        let settings = settings::test(&cx).1;
3680        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndef\nghi\n", cx));
3681        let (_, view) = cx.add_window(Default::default(), |cx| {
3682            Editor::for_buffer(buffer, settings, cx)
3683        });
3684        view.update(cx, |view, cx| {
3685            view.select_display_ranges(
3686                &[
3687                    DisplayPoint::new(0, 1)..DisplayPoint::new(1, 1),
3688                    DisplayPoint::new(1, 2)..DisplayPoint::new(2, 1),
3689                ],
3690                cx,
3691            )
3692            .unwrap();
3693            view.duplicate_line(&DuplicateLine, cx);
3694            assert_eq!(view.display_text(cx), "abc\ndef\nghi\nabc\ndef\nghi\n");
3695            assert_eq!(
3696                view.selection_ranges(cx),
3697                vec![
3698                    DisplayPoint::new(3, 1)..DisplayPoint::new(4, 1),
3699                    DisplayPoint::new(4, 2)..DisplayPoint::new(5, 1),
3700                ]
3701            );
3702        });
3703    }
3704
3705    #[gpui::test]
3706    fn test_move_line_up_down(cx: &mut gpui::MutableAppContext) {
3707        let settings = settings::test(&cx).1;
3708        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(10, 5), cx));
3709        let (_, view) = cx.add_window(Default::default(), |cx| {
3710            Editor::for_buffer(buffer, settings, cx)
3711        });
3712        view.update(cx, |view, cx| {
3713            view.fold_ranges(
3714                vec![
3715                    Point::new(0, 2)..Point::new(1, 2),
3716                    Point::new(2, 3)..Point::new(4, 1),
3717                    Point::new(7, 0)..Point::new(8, 4),
3718                ],
3719                cx,
3720            );
3721            view.select_display_ranges(
3722                &[
3723                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3724                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
3725                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
3726                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2),
3727                ],
3728                cx,
3729            )
3730            .unwrap();
3731            assert_eq!(
3732                view.display_text(cx),
3733                "aa…bbb\nccc…eeee\nfffff\nggggg\n…i\njjjjj"
3734            );
3735
3736            view.move_line_up(&MoveLineUp, cx);
3737            assert_eq!(
3738                view.display_text(cx),
3739                "aa…bbb\nccc…eeee\nggggg\n…i\njjjjj\nfffff"
3740            );
3741            assert_eq!(
3742                view.selection_ranges(cx),
3743                vec![
3744                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3745                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
3746                    DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3),
3747                    DisplayPoint::new(4, 0)..DisplayPoint::new(4, 2)
3748                ]
3749            );
3750        });
3751
3752        view.update(cx, |view, cx| {
3753            view.move_line_down(&MoveLineDown, cx);
3754            assert_eq!(
3755                view.display_text(cx),
3756                "ccc…eeee\naa…bbb\nfffff\nggggg\n…i\njjjjj"
3757            );
3758            assert_eq!(
3759                view.selection_ranges(cx),
3760                vec![
3761                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
3762                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
3763                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
3764                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2)
3765                ]
3766            );
3767        });
3768
3769        view.update(cx, |view, cx| {
3770            view.move_line_down(&MoveLineDown, cx);
3771            assert_eq!(
3772                view.display_text(cx),
3773                "ccc…eeee\nfffff\naa…bbb\nggggg\n…i\njjjjj"
3774            );
3775            assert_eq!(
3776                view.selection_ranges(cx),
3777                vec![
3778                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
3779                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 1),
3780                    DisplayPoint::new(3, 2)..DisplayPoint::new(4, 3),
3781                    DisplayPoint::new(5, 0)..DisplayPoint::new(5, 2)
3782                ]
3783            );
3784        });
3785
3786        view.update(cx, |view, cx| {
3787            view.move_line_up(&MoveLineUp, cx);
3788            assert_eq!(
3789                view.display_text(cx),
3790                "ccc…eeee\naa…bbb\nggggg\n…i\njjjjj\nfffff"
3791            );
3792            assert_eq!(
3793                view.selection_ranges(cx),
3794                vec![
3795                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
3796                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
3797                    DisplayPoint::new(2, 2)..DisplayPoint::new(3, 3),
3798                    DisplayPoint::new(4, 0)..DisplayPoint::new(4, 2)
3799                ]
3800            );
3801        });
3802    }
3803
3804    #[gpui::test]
3805    fn test_clipboard(cx: &mut gpui::MutableAppContext) {
3806        let buffer = cx.add_model(|cx| Buffer::new(0, "one two three four five six ", cx));
3807        let settings = settings::test(&cx).1;
3808        let view = cx
3809            .add_window(Default::default(), |cx| {
3810                Editor::for_buffer(buffer.clone(), settings, cx)
3811            })
3812            .1;
3813
3814        // Cut with three selections. Clipboard text is divided into three slices.
3815        view.update(cx, |view, cx| {
3816            view.select_ranges(vec![0..4, 8..14, 19..24], false, cx);
3817            view.cut(&Cut, cx);
3818            assert_eq!(view.display_text(cx), "two four six ");
3819        });
3820
3821        // Paste with three cursors. Each cursor pastes one slice of the clipboard text.
3822        view.update(cx, |view, cx| {
3823            view.select_ranges(vec![4..4, 9..9, 13..13], false, cx);
3824            view.paste(&Paste, cx);
3825            assert_eq!(view.display_text(cx), "two one four three six five ");
3826            assert_eq!(
3827                view.selection_ranges(cx),
3828                &[
3829                    DisplayPoint::new(0, 8)..DisplayPoint::new(0, 8),
3830                    DisplayPoint::new(0, 19)..DisplayPoint::new(0, 19),
3831                    DisplayPoint::new(0, 28)..DisplayPoint::new(0, 28)
3832                ]
3833            );
3834        });
3835
3836        // Paste again but with only two cursors. Since the number of cursors doesn't
3837        // match the number of slices in the clipboard, the entire clipboard text
3838        // is pasted at each cursor.
3839        view.update(cx, |view, cx| {
3840            view.select_ranges(vec![0..0, 28..28], false, cx);
3841            view.insert(&Insert("( ".into()), cx);
3842            view.paste(&Paste, cx);
3843            view.insert(&Insert(") ".into()), cx);
3844            assert_eq!(
3845                view.display_text(cx),
3846                "( one three five ) two one four three six five ( one three five ) "
3847            );
3848        });
3849
3850        view.update(cx, |view, cx| {
3851            view.select_ranges(vec![0..0], false, cx);
3852            view.insert(&Insert("123\n4567\n89\n".into()), cx);
3853            assert_eq!(
3854                view.display_text(cx),
3855                "123\n4567\n89\n( one three five ) two one four three six five ( one three five ) "
3856            );
3857        });
3858
3859        // Cut with three selections, one of which is full-line.
3860        view.update(cx, |view, cx| {
3861            view.select_display_ranges(
3862                &[
3863                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 2),
3864                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
3865                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 1),
3866                ],
3867                cx,
3868            )
3869            .unwrap();
3870            view.cut(&Cut, cx);
3871            assert_eq!(
3872                view.display_text(cx),
3873                "13\n9\n( one three five ) two one four three six five ( one three five ) "
3874            );
3875        });
3876
3877        // Paste with three selections, noticing how the copied selection that was full-line
3878        // gets inserted before the second cursor.
3879        view.update(cx, |view, cx| {
3880            view.select_display_ranges(
3881                &[
3882                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3883                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
3884                    DisplayPoint::new(2, 2)..DisplayPoint::new(2, 3),
3885                ],
3886                cx,
3887            )
3888            .unwrap();
3889            view.paste(&Paste, cx);
3890            assert_eq!(
3891                view.display_text(cx),
3892                "123\n4567\n9\n( 8ne three five ) two one four three six five ( one three five ) "
3893            );
3894            assert_eq!(
3895                view.selection_ranges(cx),
3896                &[
3897                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3898                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
3899                    DisplayPoint::new(3, 3)..DisplayPoint::new(3, 3),
3900                ]
3901            );
3902        });
3903
3904        // Copy with a single cursor only, which writes the whole line into the clipboard.
3905        view.update(cx, |view, cx| {
3906            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1)], cx)
3907                .unwrap();
3908            view.copy(&Copy, cx);
3909        });
3910
3911        // Paste with three selections, noticing how the copied full-line selection is inserted
3912        // before the empty selections but replaces the selection that is non-empty.
3913        view.update(cx, |view, cx| {
3914            view.select_display_ranges(
3915                &[
3916                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
3917                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 2),
3918                    DisplayPoint::new(2, 1)..DisplayPoint::new(2, 1),
3919                ],
3920                cx,
3921            )
3922            .unwrap();
3923            view.paste(&Paste, cx);
3924            assert_eq!(
3925                view.display_text(cx),
3926                "123\n123\n123\n67\n123\n9\n( 8ne three five ) two one four three six five ( one three five ) "
3927            );
3928            assert_eq!(
3929                view.selection_ranges(cx),
3930                &[
3931                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 1),
3932                    DisplayPoint::new(3, 0)..DisplayPoint::new(3, 0),
3933                    DisplayPoint::new(5, 1)..DisplayPoint::new(5, 1),
3934                ]
3935            );
3936        });
3937    }
3938
3939    #[gpui::test]
3940    fn test_select_all(cx: &mut gpui::MutableAppContext) {
3941        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\nde\nfgh", cx));
3942        let settings = settings::test(&cx).1;
3943        let (_, view) = cx.add_window(Default::default(), |cx| {
3944            Editor::for_buffer(buffer, settings, cx)
3945        });
3946        view.update(cx, |view, cx| {
3947            view.select_all(&SelectAll, cx);
3948            assert_eq!(
3949                view.selection_ranges(cx),
3950                &[DisplayPoint::new(0, 0)..DisplayPoint::new(2, 3)]
3951            );
3952        });
3953    }
3954
3955    #[gpui::test]
3956    fn test_select_line(cx: &mut gpui::MutableAppContext) {
3957        let settings = settings::test(&cx).1;
3958        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 5), cx));
3959        let (_, view) = cx.add_window(Default::default(), |cx| {
3960            Editor::for_buffer(buffer, settings, cx)
3961        });
3962        view.update(cx, |view, cx| {
3963            view.select_display_ranges(
3964                &[
3965                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
3966                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
3967                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
3968                    DisplayPoint::new(4, 2)..DisplayPoint::new(4, 2),
3969                ],
3970                cx,
3971            )
3972            .unwrap();
3973            view.select_line(&SelectLine, cx);
3974            assert_eq!(
3975                view.selection_ranges(cx),
3976                vec![
3977                    DisplayPoint::new(0, 0)..DisplayPoint::new(2, 0),
3978                    DisplayPoint::new(4, 0)..DisplayPoint::new(5, 0),
3979                ]
3980            );
3981        });
3982
3983        view.update(cx, |view, cx| {
3984            view.select_line(&SelectLine, cx);
3985            assert_eq!(
3986                view.selection_ranges(cx),
3987                vec![
3988                    DisplayPoint::new(0, 0)..DisplayPoint::new(3, 0),
3989                    DisplayPoint::new(4, 0)..DisplayPoint::new(5, 5),
3990                ]
3991            );
3992        });
3993
3994        view.update(cx, |view, cx| {
3995            view.select_line(&SelectLine, cx);
3996            assert_eq!(
3997                view.selection_ranges(cx),
3998                vec![DisplayPoint::new(0, 0)..DisplayPoint::new(5, 5)]
3999            );
4000        });
4001    }
4002
4003    #[gpui::test]
4004    fn test_split_selection_into_lines(cx: &mut gpui::MutableAppContext) {
4005        let settings = settings::test(&cx).1;
4006        let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(9, 5), cx));
4007        let (_, view) = cx.add_window(Default::default(), |cx| {
4008            Editor::for_buffer(buffer, settings, cx)
4009        });
4010        view.update(cx, |view, cx| {
4011            view.fold_ranges(
4012                vec![
4013                    Point::new(0, 2)..Point::new(1, 2),
4014                    Point::new(2, 3)..Point::new(4, 1),
4015                    Point::new(7, 0)..Point::new(8, 4),
4016                ],
4017                cx,
4018            );
4019            view.select_display_ranges(
4020                &[
4021                    DisplayPoint::new(0, 0)..DisplayPoint::new(0, 1),
4022                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4023                    DisplayPoint::new(1, 0)..DisplayPoint::new(1, 0),
4024                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 4),
4025                ],
4026                cx,
4027            )
4028            .unwrap();
4029            assert_eq!(view.display_text(cx), "aa…bbb\nccc…eeee\nfffff\nggggg\n…i");
4030        });
4031
4032        view.update(cx, |view, cx| {
4033            view.split_selection_into_lines(&SplitSelectionIntoLines, cx);
4034            assert_eq!(
4035                view.display_text(cx),
4036                "aaaaa\nbbbbb\nccc…eeee\nfffff\nggggg\n…i"
4037            );
4038            assert_eq!(
4039                view.selection_ranges(cx),
4040                [
4041                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4042                    DisplayPoint::new(0, 2)..DisplayPoint::new(0, 2),
4043                    DisplayPoint::new(2, 0)..DisplayPoint::new(2, 0),
4044                    DisplayPoint::new(5, 4)..DisplayPoint::new(5, 4)
4045                ]
4046            );
4047        });
4048
4049        view.update(cx, |view, cx| {
4050            view.select_display_ranges(&[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 1)], cx)
4051                .unwrap();
4052            view.split_selection_into_lines(&SplitSelectionIntoLines, cx);
4053            assert_eq!(
4054                view.display_text(cx),
4055                "aaaaa\nbbbbb\nccccc\nddddd\neeeee\nfffff\nggggg\nhhhhh\niiiii"
4056            );
4057            assert_eq!(
4058                view.selection_ranges(cx),
4059                [
4060                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 1),
4061                    DisplayPoint::new(1, 5)..DisplayPoint::new(1, 5),
4062                    DisplayPoint::new(2, 5)..DisplayPoint::new(2, 5),
4063                    DisplayPoint::new(3, 5)..DisplayPoint::new(3, 5),
4064                    DisplayPoint::new(4, 5)..DisplayPoint::new(4, 5),
4065                    DisplayPoint::new(5, 5)..DisplayPoint::new(5, 5),
4066                    DisplayPoint::new(6, 5)..DisplayPoint::new(6, 5),
4067                    DisplayPoint::new(7, 0)..DisplayPoint::new(7, 0)
4068                ]
4069            );
4070        });
4071    }
4072
4073    #[gpui::test]
4074    fn test_add_selection_above_below(cx: &mut gpui::MutableAppContext) {
4075        let settings = settings::test(&cx).1;
4076        let buffer = cx.add_model(|cx| Buffer::new(0, "abc\ndefghi\n\njk\nlmno\n", cx));
4077        let (_, view) = cx.add_window(Default::default(), |cx| {
4078            Editor::for_buffer(buffer, settings, cx)
4079        });
4080
4081        view.update(cx, |view, cx| {
4082            view.select_display_ranges(&[DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)], cx)
4083                .unwrap();
4084        });
4085        view.update(cx, |view, cx| {
4086            view.add_selection_above(&AddSelectionAbove, cx);
4087            assert_eq!(
4088                view.selection_ranges(cx),
4089                vec![
4090                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
4091                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)
4092                ]
4093            );
4094        });
4095
4096        view.update(cx, |view, cx| {
4097            view.add_selection_above(&AddSelectionAbove, cx);
4098            assert_eq!(
4099                view.selection_ranges(cx),
4100                vec![
4101                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 3),
4102                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)
4103                ]
4104            );
4105        });
4106
4107        view.update(cx, |view, cx| {
4108            view.add_selection_below(&AddSelectionBelow, cx);
4109            assert_eq!(
4110                view.selection_ranges(cx),
4111                vec![DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3)]
4112            );
4113        });
4114
4115        view.update(cx, |view, cx| {
4116            view.add_selection_below(&AddSelectionBelow, cx);
4117            assert_eq!(
4118                view.selection_ranges(cx),
4119                vec![
4120                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3),
4121                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 3)
4122                ]
4123            );
4124        });
4125
4126        view.update(cx, |view, cx| {
4127            view.add_selection_below(&AddSelectionBelow, cx);
4128            assert_eq!(
4129                view.selection_ranges(cx),
4130                vec![
4131                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 3),
4132                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 3)
4133                ]
4134            );
4135        });
4136
4137        view.update(cx, |view, cx| {
4138            view.select_display_ranges(&[DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)], cx)
4139                .unwrap();
4140        });
4141        view.update(cx, |view, cx| {
4142            view.add_selection_below(&AddSelectionBelow, cx);
4143            assert_eq!(
4144                view.selection_ranges(cx),
4145                vec![
4146                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
4147                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 3)
4148                ]
4149            );
4150        });
4151
4152        view.update(cx, |view, cx| {
4153            view.add_selection_below(&AddSelectionBelow, cx);
4154            assert_eq!(
4155                view.selection_ranges(cx),
4156                vec![
4157                    DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3),
4158                    DisplayPoint::new(4, 4)..DisplayPoint::new(4, 3)
4159                ]
4160            );
4161        });
4162
4163        view.update(cx, |view, cx| {
4164            view.add_selection_above(&AddSelectionAbove, cx);
4165            assert_eq!(
4166                view.selection_ranges(cx),
4167                vec![DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)]
4168            );
4169        });
4170
4171        view.update(cx, |view, cx| {
4172            view.add_selection_above(&AddSelectionAbove, cx);
4173            assert_eq!(
4174                view.selection_ranges(cx),
4175                vec![DisplayPoint::new(1, 4)..DisplayPoint::new(1, 3)]
4176            );
4177        });
4178
4179        view.update(cx, |view, cx| {
4180            view.select_display_ranges(&[DisplayPoint::new(0, 1)..DisplayPoint::new(1, 4)], cx)
4181                .unwrap();
4182            view.add_selection_below(&AddSelectionBelow, cx);
4183            assert_eq!(
4184                view.selection_ranges(cx),
4185                vec![
4186                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4187                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4188                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4189                ]
4190            );
4191        });
4192
4193        view.update(cx, |view, cx| {
4194            view.add_selection_below(&AddSelectionBelow, cx);
4195            assert_eq!(
4196                view.selection_ranges(cx),
4197                vec![
4198                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4199                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4200                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4201                    DisplayPoint::new(4, 1)..DisplayPoint::new(4, 4),
4202                ]
4203            );
4204        });
4205
4206        view.update(cx, |view, cx| {
4207            view.add_selection_above(&AddSelectionAbove, cx);
4208            assert_eq!(
4209                view.selection_ranges(cx),
4210                vec![
4211                    DisplayPoint::new(0, 1)..DisplayPoint::new(0, 3),
4212                    DisplayPoint::new(1, 1)..DisplayPoint::new(1, 4),
4213                    DisplayPoint::new(3, 1)..DisplayPoint::new(3, 2),
4214                ]
4215            );
4216        });
4217
4218        view.update(cx, |view, cx| {
4219            view.select_display_ranges(&[DisplayPoint::new(4, 3)..DisplayPoint::new(1, 1)], cx)
4220                .unwrap();
4221        });
4222        view.update(cx, |view, cx| {
4223            view.add_selection_above(&AddSelectionAbove, cx);
4224            assert_eq!(
4225                view.selection_ranges(cx),
4226                vec![
4227                    DisplayPoint::new(0, 3)..DisplayPoint::new(0, 1),
4228                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 1),
4229                    DisplayPoint::new(3, 2)..DisplayPoint::new(3, 1),
4230                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 1),
4231                ]
4232            );
4233        });
4234
4235        view.update(cx, |view, cx| {
4236            view.add_selection_below(&AddSelectionBelow, cx);
4237            assert_eq!(
4238                view.selection_ranges(cx),
4239                vec![
4240                    DisplayPoint::new(1, 3)..DisplayPoint::new(1, 1),
4241                    DisplayPoint::new(3, 2)..DisplayPoint::new(3, 1),
4242                    DisplayPoint::new(4, 3)..DisplayPoint::new(4, 1),
4243                ]
4244            );
4245        });
4246    }
4247
4248    #[gpui::test]
4249    async fn test_select_larger_smaller_syntax_node(mut cx: gpui::TestAppContext) {
4250        let settings = cx.read(settings::test).1;
4251        let languages = LanguageRegistry::new();
4252        let lang = languages.select_language("z.rs");
4253        let text = r#"
4254            use mod1::mod2::{mod3, mod4};
4255
4256            fn fn_1(param1: bool, param2: &str) {
4257                let var1 = "text";
4258            }
4259        "#
4260        .unindent();
4261        let buffer = cx.add_model(|cx| {
4262            let history = History::new(text.into());
4263            Buffer::from_history(0, history, None, lang.cloned(), cx)
4264        });
4265        let (_, view) = cx.add_window(|cx| Editor::for_buffer(buffer, settings.clone(), cx));
4266        view.condition(&cx, |view, cx| !view.buffer.read(cx).is_parsing())
4267            .await;
4268
4269        view.update(&mut cx, |view, cx| {
4270            view.select_display_ranges(
4271                &[
4272                    DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4273                    DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4274                    DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4275                ],
4276                cx,
4277            )
4278            .unwrap();
4279            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4280        });
4281        assert_eq!(
4282            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4283            &[
4284                DisplayPoint::new(0, 23)..DisplayPoint::new(0, 27),
4285                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4286                DisplayPoint::new(3, 15)..DisplayPoint::new(3, 21),
4287            ]
4288        );
4289
4290        view.update(&mut cx, |view, cx| {
4291            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4292        });
4293        assert_eq!(
4294            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4295            &[
4296                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4297                DisplayPoint::new(4, 1)..DisplayPoint::new(2, 0),
4298            ]
4299        );
4300
4301        view.update(&mut cx, |view, cx| {
4302            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4303        });
4304        assert_eq!(
4305            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4306            &[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 0)]
4307        );
4308
4309        // Trying to expand the selected syntax node one more time has no effect.
4310        view.update(&mut cx, |view, cx| {
4311            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4312        });
4313        assert_eq!(
4314            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4315            &[DisplayPoint::new(5, 0)..DisplayPoint::new(0, 0)]
4316        );
4317
4318        view.update(&mut cx, |view, cx| {
4319            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4320        });
4321        assert_eq!(
4322            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4323            &[
4324                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4325                DisplayPoint::new(4, 1)..DisplayPoint::new(2, 0),
4326            ]
4327        );
4328
4329        view.update(&mut cx, |view, cx| {
4330            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4331        });
4332        assert_eq!(
4333            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4334            &[
4335                DisplayPoint::new(0, 23)..DisplayPoint::new(0, 27),
4336                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4337                DisplayPoint::new(3, 15)..DisplayPoint::new(3, 21),
4338            ]
4339        );
4340
4341        view.update(&mut cx, |view, cx| {
4342            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4343        });
4344        assert_eq!(
4345            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4346            &[
4347                DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4348                DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4349                DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4350            ]
4351        );
4352
4353        // Trying to shrink the selected syntax node one more time has no effect.
4354        view.update(&mut cx, |view, cx| {
4355            view.select_smaller_syntax_node(&SelectSmallerSyntaxNode, cx);
4356        });
4357        assert_eq!(
4358            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4359            &[
4360                DisplayPoint::new(0, 25)..DisplayPoint::new(0, 25),
4361                DisplayPoint::new(2, 24)..DisplayPoint::new(2, 12),
4362                DisplayPoint::new(3, 18)..DisplayPoint::new(3, 18),
4363            ]
4364        );
4365
4366        // Ensure that we keep expanding the selection if the larger selection starts or ends within
4367        // a fold.
4368        view.update(&mut cx, |view, cx| {
4369            view.fold_ranges(
4370                vec![
4371                    Point::new(0, 21)..Point::new(0, 24),
4372                    Point::new(3, 20)..Point::new(3, 22),
4373                ],
4374                cx,
4375            );
4376            view.select_larger_syntax_node(&SelectLargerSyntaxNode, cx);
4377        });
4378        assert_eq!(
4379            view.update(&mut cx, |view, cx| view.selection_ranges(cx)),
4380            &[
4381                DisplayPoint::new(0, 16)..DisplayPoint::new(0, 28),
4382                DisplayPoint::new(2, 35)..DisplayPoint::new(2, 7),
4383                DisplayPoint::new(3, 4)..DisplayPoint::new(3, 23),
4384            ]
4385        );
4386    }
4387
4388    impl Editor {
4389        fn selection_ranges(&self, cx: &mut MutableAppContext) -> Vec<Range<DisplayPoint>> {
4390            self.selections_in_range(
4391                self.selection_set_id,
4392                DisplayPoint::zero()..self.max_point(cx),
4393                cx,
4394            )
4395            .collect::<Vec<_>>()
4396        }
4397    }
4398
4399    fn empty_range(row: usize, column: usize) -> Range<DisplayPoint> {
4400        let point = DisplayPoint::new(row as u32, column as u32);
4401        point..point
4402    }
4403}
4404
4405trait RangeExt<T> {
4406    fn sorted(&self) -> Range<T>;
4407    fn to_inclusive(&self) -> RangeInclusive<T>;
4408}
4409
4410impl<T: Ord + Clone> RangeExt<T> for Range<T> {
4411    fn sorted(&self) -> Self {
4412        cmp::min(&self.start, &self.end).clone()..cmp::max(&self.start, &self.end).clone()
4413    }
4414
4415    fn to_inclusive(&self) -> RangeInclusive<T> {
4416        self.start.clone()..=self.end.clone()
4417    }
4418}