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