1use super::{
   2    display_map::{BlockContext, ToDisplayPoint},
   3    Anchor, DisplayPoint, Editor, EditorMode, EditorSnapshot, SelectPhase, SoftWrap, ToPoint,
   4    MAX_LINE_LEN,
   5};
   6use crate::{
   7    display_map::{BlockStyle, DisplaySnapshot, FoldStatus, TransformBlock},
   8    git::{diff_hunk_to_display, DisplayDiffHunk},
   9    hover_popover::{
  10        hide_hover, hover_at, HOVER_POPOVER_GAP, MIN_POPOVER_CHARACTER_WIDTH,
  11        MIN_POPOVER_LINE_HEIGHT,
  12    },
  13    link_go_to_definition::{
  14        go_to_fetched_definition, go_to_fetched_type_definition, update_go_to_definition_link,
  15    },
  16    mouse_context_menu, EditorStyle, GutterHover, UnfoldAt,
  17};
  18use clock::ReplicaId;
  19use collections::{BTreeMap, HashMap};
  20use git::diff::DiffHunkStatus;
  21use gpui::{
  22    color::Color,
  23    elements::*,
  24    fonts::{HighlightStyle, TextStyle, Underline},
  25    geometry::{
  26        rect::RectF,
  27        vector::{vec2f, Vector2F},
  28        PathBuilder,
  29    },
  30    json::{self, ToJson},
  31    platform::{CursorStyle, Modifiers, MouseButton, MouseButtonEvent, MouseMovedEvent},
  32    text_layout::{self, Line, RunStyle, TextLayoutCache},
  33    AnyElement, Axis, Border, CursorRegion, Element, EventContext, FontCache, LayoutContext,
  34    MouseRegion, Quad, SceneBuilder, SizeConstraint, ViewContext, WindowContext,
  35};
  36use itertools::Itertools;
  37use json::json;
  38use language::{Bias, CursorShape, DiagnosticSeverity, OffsetUtf16, Selection};
  39use project::ProjectPath;
  40use settings::{GitGutter, Settings, ShowWhitespaces};
  41use smallvec::SmallVec;
  42use std::{
  43    borrow::Cow,
  44    cmp::{self, Ordering},
  45    fmt::Write,
  46    iter,
  47    ops::Range,
  48    sync::Arc,
  49};
  50use workspace::item::Item;
  51
  52enum FoldMarkers {}
  53
  54struct SelectionLayout {
  55    head: DisplayPoint,
  56    cursor_shape: CursorShape,
  57    range: Range<DisplayPoint>,
  58}
  59
  60impl SelectionLayout {
  61    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  62        selection: Selection<T>,
  63        line_mode: bool,
  64        cursor_shape: CursorShape,
  65        map: &DisplaySnapshot,
  66    ) -> Self {
  67        if line_mode {
  68            let selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  69            let point_range = map.expand_to_line(selection.range());
  70            Self {
  71                head: selection.head().to_display_point(map),
  72                cursor_shape,
  73                range: point_range.start.to_display_point(map)
  74                    ..point_range.end.to_display_point(map),
  75            }
  76        } else {
  77            let selection = selection.map(|p| p.to_display_point(map));
  78            Self {
  79                head: selection.head(),
  80                cursor_shape,
  81                range: selection.range(),
  82            }
  83        }
  84    }
  85}
  86
  87#[derive(Clone)]
  88pub struct EditorElement {
  89    style: Arc<EditorStyle>,
  90}
  91
  92impl EditorElement {
  93    pub fn new(style: EditorStyle) -> Self {
  94        Self {
  95            style: Arc::new(style),
  96        }
  97    }
  98
  99    fn attach_mouse_handlers(
 100        scene: &mut SceneBuilder,
 101        position_map: &Arc<PositionMap>,
 102        has_popovers: bool,
 103        visible_bounds: RectF,
 104        text_bounds: RectF,
 105        gutter_bounds: RectF,
 106        bounds: RectF,
 107        cx: &mut ViewContext<Editor>,
 108    ) {
 109        enum EditorElementMouseHandlers {}
 110        scene.push_mouse_region(
 111            MouseRegion::new::<EditorElementMouseHandlers>(
 112                cx.view_id(),
 113                cx.view_id(),
 114                visible_bounds,
 115            )
 116            .on_down(MouseButton::Left, {
 117                let position_map = position_map.clone();
 118                move |event, editor, cx| {
 119                    if !Self::mouse_down(
 120                        editor,
 121                        event.platform_event,
 122                        position_map.as_ref(),
 123                        text_bounds,
 124                        gutter_bounds,
 125                        cx,
 126                    ) {
 127                        cx.propagate_event();
 128                    }
 129                }
 130            })
 131            .on_down(MouseButton::Right, {
 132                let position_map = position_map.clone();
 133                move |event, editor, cx| {
 134                    if !Self::mouse_right_down(
 135                        editor,
 136                        event.position,
 137                        position_map.as_ref(),
 138                        text_bounds,
 139                        cx,
 140                    ) {
 141                        cx.propagate_event();
 142                    }
 143                }
 144            })
 145            .on_up(MouseButton::Left, {
 146                let position_map = position_map.clone();
 147                move |event, editor, cx| {
 148                    if !Self::mouse_up(
 149                        editor,
 150                        event.position,
 151                        event.cmd,
 152                        event.shift,
 153                        position_map.as_ref(),
 154                        text_bounds,
 155                        cx,
 156                    ) {
 157                        cx.propagate_event()
 158                    }
 159                }
 160            })
 161            .on_drag(MouseButton::Left, {
 162                let position_map = position_map.clone();
 163                move |event, editor, cx| {
 164                    if !Self::mouse_dragged(
 165                        editor,
 166                        event.platform_event,
 167                        position_map.as_ref(),
 168                        text_bounds,
 169                        cx,
 170                    ) {
 171                        cx.propagate_event()
 172                    }
 173                }
 174            })
 175            .on_move({
 176                let position_map = position_map.clone();
 177                move |event, editor, cx| {
 178                    if !Self::mouse_moved(
 179                        editor,
 180                        event.platform_event,
 181                        &position_map,
 182                        text_bounds,
 183                        cx,
 184                    ) {
 185                        cx.propagate_event()
 186                    }
 187                }
 188            })
 189            .on_move_out(move |_, editor: &mut Editor, cx| {
 190                if has_popovers {
 191                    hide_hover(editor, cx);
 192                }
 193            })
 194            .on_scroll({
 195                let position_map = position_map.clone();
 196                move |event, editor, cx| {
 197                    if !Self::scroll(
 198                        editor,
 199                        event.position,
 200                        *event.delta.raw(),
 201                        event.delta.precise(),
 202                        &position_map,
 203                        bounds,
 204                        cx,
 205                    ) {
 206                        cx.propagate_event()
 207                    }
 208                }
 209            }),
 210        );
 211
 212        enum GutterHandlers {}
 213        scene.push_mouse_region(
 214            MouseRegion::new::<GutterHandlers>(cx.view_id(), cx.view_id() + 1, gutter_bounds)
 215                .on_hover(|hover, editor: &mut Editor, cx| {
 216                    editor.gutter_hover(
 217                        &GutterHover {
 218                            hovered: hover.started,
 219                        },
 220                        cx,
 221                    );
 222                }),
 223        )
 224    }
 225
 226    fn mouse_down(
 227        editor: &mut Editor,
 228        MouseButtonEvent {
 229            position,
 230            modifiers:
 231                Modifiers {
 232                    shift,
 233                    ctrl,
 234                    alt,
 235                    cmd,
 236                    ..
 237                },
 238            mut click_count,
 239            ..
 240        }: MouseButtonEvent,
 241        position_map: &PositionMap,
 242        text_bounds: RectF,
 243        gutter_bounds: RectF,
 244        cx: &mut EventContext<Editor>,
 245    ) -> bool {
 246        if gutter_bounds.contains_point(position) {
 247            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 248        } else if !text_bounds.contains_point(position) {
 249            return false;
 250        }
 251
 252        let (position, target_position) = position_map.point_for_position(text_bounds, position);
 253
 254        if shift && alt {
 255            editor.select(
 256                SelectPhase::BeginColumnar {
 257                    position,
 258                    goal_column: target_position.column(),
 259                },
 260                cx,
 261            );
 262        } else if shift && !ctrl && !alt && !cmd {
 263            editor.select(
 264                SelectPhase::Extend {
 265                    position,
 266                    click_count,
 267                },
 268                cx,
 269            );
 270        } else {
 271            editor.select(
 272                SelectPhase::Begin {
 273                    position,
 274                    add: alt,
 275                    click_count,
 276                },
 277                cx,
 278            );
 279        }
 280
 281        true
 282    }
 283
 284    fn mouse_right_down(
 285        editor: &mut Editor,
 286        position: Vector2F,
 287        position_map: &PositionMap,
 288        text_bounds: RectF,
 289        cx: &mut EventContext<Editor>,
 290    ) -> bool {
 291        if !text_bounds.contains_point(position) {
 292            return false;
 293        }
 294
 295        let (point, _) = position_map.point_for_position(text_bounds, position);
 296        mouse_context_menu::deploy_context_menu(editor, position, point, cx);
 297        true
 298    }
 299
 300    fn mouse_up(
 301        editor: &mut Editor,
 302        position: Vector2F,
 303        cmd: bool,
 304        shift: bool,
 305        position_map: &PositionMap,
 306        text_bounds: RectF,
 307        cx: &mut EventContext<Editor>,
 308    ) -> bool {
 309        let end_selection = editor.has_pending_selection();
 310        let pending_nonempty_selections = editor.has_pending_nonempty_selection();
 311
 312        if end_selection {
 313            editor.select(SelectPhase::End, cx);
 314        }
 315
 316        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 317            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 318
 319            if point == target_point {
 320                if shift {
 321                    go_to_fetched_type_definition(editor, point, cx);
 322                } else {
 323                    go_to_fetched_definition(editor, point, cx);
 324                }
 325
 326                return true;
 327            }
 328        }
 329
 330        end_selection
 331    }
 332
 333    fn mouse_dragged(
 334        editor: &mut Editor,
 335        MouseMovedEvent {
 336            modifiers: Modifiers { cmd, shift, .. },
 337            position,
 338            ..
 339        }: MouseMovedEvent,
 340        position_map: &PositionMap,
 341        text_bounds: RectF,
 342        cx: &mut EventContext<Editor>,
 343    ) -> bool {
 344        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 345        // Don't trigger hover popover if mouse is hovering over context menu
 346        let point = if text_bounds.contains_point(position) {
 347            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 348            if point == target_point {
 349                Some(point)
 350            } else {
 351                None
 352            }
 353        } else {
 354            None
 355        };
 356
 357        update_go_to_definition_link(editor, point, cmd, shift, cx);
 358
 359        if editor.has_pending_selection() {
 360            let mut scroll_delta = Vector2F::zero();
 361
 362            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 363            let top = text_bounds.origin_y() + vertical_margin;
 364            let bottom = text_bounds.lower_left().y() - vertical_margin;
 365            if position.y() < top {
 366                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 367            }
 368            if position.y() > bottom {
 369                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 370            }
 371
 372            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 373            let left = text_bounds.origin_x() + horizontal_margin;
 374            let right = text_bounds.upper_right().x() - horizontal_margin;
 375            if position.x() < left {
 376                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 377                    left - position.x(),
 378                ))
 379            }
 380            if position.x() > right {
 381                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 382                    position.x() - right,
 383                ))
 384            }
 385
 386            let (position, target_position) =
 387                position_map.point_for_position(text_bounds, position);
 388
 389            editor.select(
 390                SelectPhase::Update {
 391                    position,
 392                    goal_column: target_position.column(),
 393                    scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 394                        .clamp(Vector2F::zero(), position_map.scroll_max),
 395                },
 396                cx,
 397            );
 398            hover_at(editor, point, cx);
 399            true
 400        } else {
 401            hover_at(editor, point, cx);
 402            false
 403        }
 404    }
 405
 406    fn mouse_moved(
 407        editor: &mut Editor,
 408        MouseMovedEvent {
 409            modifiers: Modifiers { shift, cmd, .. },
 410            position,
 411            ..
 412        }: MouseMovedEvent,
 413        position_map: &PositionMap,
 414        text_bounds: RectF,
 415        cx: &mut ViewContext<Editor>,
 416    ) -> bool {
 417        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 418        // Don't trigger hover popover if mouse is hovering over context menu
 419        let point = position_to_display_point(position, text_bounds, position_map);
 420
 421        update_go_to_definition_link(editor, point, cmd, shift, cx);
 422        hover_at(editor, point, cx);
 423
 424        true
 425    }
 426
 427    fn scroll(
 428        editor: &mut Editor,
 429        position: Vector2F,
 430        mut delta: Vector2F,
 431        precise: bool,
 432        position_map: &PositionMap,
 433        bounds: RectF,
 434        cx: &mut ViewContext<Editor>,
 435    ) -> bool {
 436        if !bounds.contains_point(position) {
 437            return false;
 438        }
 439
 440        let line_height = position_map.line_height;
 441        let max_glyph_width = position_map.em_width;
 442
 443        let axis = if precise {
 444            //Trackpad
 445            position_map.snapshot.ongoing_scroll.filter(&mut delta)
 446        } else {
 447            //Not trackpad
 448            delta *= vec2f(max_glyph_width, line_height);
 449            None //Resets ongoing scroll
 450        };
 451
 452        let scroll_position = position_map.snapshot.scroll_position();
 453        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 454        let y = (scroll_position.y() * line_height - delta.y()) / line_height;
 455        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 456        editor.scroll(scroll_position, axis, cx);
 457
 458        true
 459    }
 460
 461    fn paint_background(
 462        &self,
 463        scene: &mut SceneBuilder,
 464        gutter_bounds: RectF,
 465        text_bounds: RectF,
 466        layout: &LayoutState,
 467    ) {
 468        let bounds = gutter_bounds.union_rect(text_bounds);
 469        let scroll_top =
 470            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 471        scene.push_quad(Quad {
 472            bounds: gutter_bounds,
 473            background: Some(self.style.gutter_background),
 474            border: Border::new(0., Color::transparent_black()),
 475            corner_radius: 0.,
 476        });
 477        scene.push_quad(Quad {
 478            bounds: text_bounds,
 479            background: Some(self.style.background),
 480            border: Border::new(0., Color::transparent_black()),
 481            corner_radius: 0.,
 482        });
 483
 484        if let EditorMode::Full = layout.mode {
 485            let mut active_rows = layout.active_rows.iter().peekable();
 486            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 487                let mut end_row = *start_row;
 488                while active_rows.peek().map_or(false, |r| {
 489                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 490                }) {
 491                    active_rows.next().unwrap();
 492                    end_row += 1;
 493                }
 494
 495                if !contains_non_empty_selection {
 496                    let origin = vec2f(
 497                        bounds.origin_x(),
 498                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 499                            - scroll_top,
 500                    );
 501                    let size = vec2f(
 502                        bounds.width(),
 503                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 504                    );
 505                    scene.push_quad(Quad {
 506                        bounds: RectF::new(origin, size),
 507                        background: Some(self.style.active_line_background),
 508                        border: Border::default(),
 509                        corner_radius: 0.,
 510                    });
 511                }
 512            }
 513
 514            if let Some(highlighted_rows) = &layout.highlighted_rows {
 515                let origin = vec2f(
 516                    bounds.origin_x(),
 517                    bounds.origin_y()
 518                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 519                        - scroll_top,
 520                );
 521                let size = vec2f(
 522                    bounds.width(),
 523                    layout.position_map.line_height * highlighted_rows.len() as f32,
 524                );
 525                scene.push_quad(Quad {
 526                    bounds: RectF::new(origin, size),
 527                    background: Some(self.style.highlighted_line_background),
 528                    border: Border::default(),
 529                    corner_radius: 0.,
 530                });
 531            }
 532        }
 533    }
 534
 535    fn paint_gutter(
 536        &mut self,
 537        scene: &mut SceneBuilder,
 538        bounds: RectF,
 539        visible_bounds: RectF,
 540        layout: &mut LayoutState,
 541        editor: &mut Editor,
 542        cx: &mut ViewContext<Editor>,
 543    ) {
 544        let line_height = layout.position_map.line_height;
 545
 546        let scroll_position = layout.position_map.snapshot.scroll_position();
 547        let scroll_top = scroll_position.y() * line_height;
 548
 549        let show_gutter = matches!(
 550            &cx.global::<Settings>()
 551                .git_overrides
 552                .git_gutter
 553                .unwrap_or_default(),
 554            GitGutter::TrackedFiles
 555        );
 556
 557        if show_gutter {
 558            Self::paint_diff_hunks(scene, bounds, layout, cx);
 559        }
 560
 561        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 562            if let Some(line) = line {
 563                let line_origin = bounds.origin()
 564                    + vec2f(
 565                        bounds.width() - line.width() - layout.gutter_padding,
 566                        ix as f32 * line_height - (scroll_top % line_height),
 567                    );
 568
 569                line.paint(scene, line_origin, visible_bounds, line_height, cx);
 570            }
 571        }
 572
 573        for (ix, fold_indicator) in layout.fold_indicators.iter_mut().enumerate() {
 574            if let Some(indicator) = fold_indicator.as_mut() {
 575                let position = vec2f(
 576                    bounds.width() - layout.gutter_padding,
 577                    ix as f32 * line_height - (scroll_top % line_height),
 578                );
 579                let centering_offset = vec2f(
 580                    (layout.gutter_padding + layout.gutter_margin - indicator.size().x()) / 2.,
 581                    (line_height - indicator.size().y()) / 2.,
 582                );
 583
 584                let indicator_origin = bounds.origin() + position + centering_offset;
 585
 586                indicator.paint(scene, indicator_origin, visible_bounds, editor, cx);
 587            }
 588        }
 589
 590        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 591            let mut x = 0.;
 592            let mut y = *row as f32 * line_height - scroll_top;
 593            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 594            y += (line_height - indicator.size().y()) / 2.;
 595            indicator.paint(
 596                scene,
 597                bounds.origin() + vec2f(x, y),
 598                visible_bounds,
 599                editor,
 600                cx,
 601            );
 602        }
 603    }
 604
 605    fn paint_diff_hunks(
 606        scene: &mut SceneBuilder,
 607        bounds: RectF,
 608        layout: &mut LayoutState,
 609        cx: &mut ViewContext<Editor>,
 610    ) {
 611        let diff_style = &cx.global::<Settings>().theme.editor.diff.clone();
 612        let line_height = layout.position_map.line_height;
 613
 614        let scroll_position = layout.position_map.snapshot.scroll_position();
 615        let scroll_top = scroll_position.y() * line_height;
 616
 617        for hunk in &layout.display_hunks {
 618            let (display_row_range, status) = match hunk {
 619                //TODO: This rendering is entirely a horrible hack
 620                &DisplayDiffHunk::Folded { display_row: row } => {
 621                    let start_y = row as f32 * line_height - scroll_top;
 622                    let end_y = start_y + line_height;
 623
 624                    let width = diff_style.removed_width_em * line_height;
 625                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 626                    let highlight_size = vec2f(width * 2., end_y - start_y);
 627                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 628
 629                    scene.push_quad(Quad {
 630                        bounds: highlight_bounds,
 631                        background: Some(diff_style.modified),
 632                        border: Border::new(0., Color::transparent_black()),
 633                        corner_radius: 1. * line_height,
 634                    });
 635
 636                    continue;
 637                }
 638
 639                DisplayDiffHunk::Unfolded {
 640                    display_row_range,
 641                    status,
 642                } => (display_row_range, status),
 643            };
 644
 645            let color = match status {
 646                DiffHunkStatus::Added => diff_style.inserted,
 647                DiffHunkStatus::Modified => diff_style.modified,
 648
 649                //TODO: This rendering is entirely a horrible hack
 650                DiffHunkStatus::Removed => {
 651                    let row = *display_row_range.start();
 652
 653                    let offset = line_height / 2.;
 654                    let start_y = row as f32 * line_height - offset - scroll_top;
 655                    let end_y = start_y + line_height;
 656
 657                    let width = diff_style.removed_width_em * line_height;
 658                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 659                    let highlight_size = vec2f(width * 2., end_y - start_y);
 660                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 661
 662                    scene.push_quad(Quad {
 663                        bounds: highlight_bounds,
 664                        background: Some(diff_style.deleted),
 665                        border: Border::new(0., Color::transparent_black()),
 666                        corner_radius: 1. * line_height,
 667                    });
 668
 669                    continue;
 670                }
 671            };
 672
 673            let start_row = *display_row_range.start();
 674            let end_row = *display_row_range.end();
 675
 676            let start_y = start_row as f32 * line_height - scroll_top;
 677            let end_y = end_row as f32 * line_height - scroll_top + line_height;
 678
 679            let width = diff_style.width_em * line_height;
 680            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 681            let highlight_size = vec2f(width * 2., end_y - start_y);
 682            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 683
 684            scene.push_quad(Quad {
 685                bounds: highlight_bounds,
 686                background: Some(color),
 687                border: Border::new(0., Color::transparent_black()),
 688                corner_radius: diff_style.corner_radius * line_height,
 689            });
 690        }
 691    }
 692
 693    fn paint_text(
 694        &mut self,
 695        scene: &mut SceneBuilder,
 696        bounds: RectF,
 697        visible_bounds: RectF,
 698        layout: &mut LayoutState,
 699        editor: &mut Editor,
 700        cx: &mut ViewContext<Editor>,
 701    ) {
 702        let style = &self.style;
 703        let local_replica_id = editor.replica_id(cx);
 704        let scroll_position = layout.position_map.snapshot.scroll_position();
 705        let start_row = layout.visible_display_row_range.start;
 706        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 707        let max_glyph_width = layout.position_map.em_width;
 708        let scroll_left = scroll_position.x() * max_glyph_width;
 709        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 710        let line_end_overshoot = 0.15 * layout.position_map.line_height;
 711
 712        scene.push_layer(Some(bounds));
 713
 714        scene.push_cursor_region(CursorRegion {
 715            bounds,
 716            style: if !editor.link_go_to_definition_state.definitions.is_empty() {
 717                CursorStyle::PointingHand
 718            } else {
 719                CursorStyle::IBeam
 720            },
 721        });
 722
 723        let fold_corner_radius =
 724            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
 725        for (id, range, color) in layout.fold_ranges.iter() {
 726            self.paint_highlighted_range(
 727                scene,
 728                range.clone(),
 729                *color,
 730                fold_corner_radius,
 731                fold_corner_radius * 2.,
 732                layout,
 733                content_origin,
 734                scroll_top,
 735                scroll_left,
 736                bounds,
 737            );
 738
 739            for bound in range_to_bounds(
 740                &range,
 741                content_origin,
 742                scroll_left,
 743                scroll_top,
 744                &layout.visible_display_row_range,
 745                line_end_overshoot,
 746                &layout.position_map,
 747            ) {
 748                scene.push_cursor_region(CursorRegion {
 749                    bounds: bound,
 750                    style: CursorStyle::PointingHand,
 751                });
 752
 753                let display_row = range.start.row();
 754
 755                let buffer_row = DisplayPoint::new(display_row, 0)
 756                    .to_point(&layout.position_map.snapshot.display_snapshot)
 757                    .row;
 758
 759                scene.push_mouse_region(
 760                    MouseRegion::new::<FoldMarkers>(cx.view_id(), *id as usize, bound)
 761                        .on_click(MouseButton::Left, move |_, editor: &mut Editor, cx| {
 762                            editor.unfold_at(&UnfoldAt { buffer_row }, cx)
 763                        })
 764                        .with_notify_on_hover(true)
 765                        .with_notify_on_click(true),
 766                )
 767            }
 768        }
 769
 770        for (range, color) in &layout.highlighted_ranges {
 771            self.paint_highlighted_range(
 772                scene,
 773                range.clone(),
 774                *color,
 775                0.,
 776                line_end_overshoot,
 777                layout,
 778                content_origin,
 779                scroll_top,
 780                scroll_left,
 781                bounds,
 782            );
 783        }
 784
 785        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 786        let corner_radius = 0.15 * layout.position_map.line_height;
 787        let mut invisible_display_ranges = SmallVec::<[Range<DisplayPoint>; 32]>::new();
 788
 789        for (replica_id, selections) in &layout.selections {
 790            let replica_id = *replica_id;
 791            let selection_style = style.replica_selection_style(replica_id);
 792
 793            for selection in selections {
 794                if !selection.range.is_empty()
 795                    && (replica_id == local_replica_id
 796                        || Some(replica_id) == editor.leader_replica_id)
 797                {
 798                    invisible_display_ranges.push(selection.range.clone());
 799                }
 800                self.paint_highlighted_range(
 801                    scene,
 802                    selection.range.clone(),
 803                    selection_style.selection,
 804                    corner_radius,
 805                    corner_radius * 2.,
 806                    layout,
 807                    content_origin,
 808                    scroll_top,
 809                    scroll_left,
 810                    bounds,
 811                );
 812
 813                if editor.show_local_cursors(cx) || replica_id != local_replica_id {
 814                    let cursor_position = selection.head;
 815                    if layout
 816                        .visible_display_row_range
 817                        .contains(&cursor_position.row())
 818                    {
 819                        let cursor_row_layout = &layout.position_map.line_layouts
 820                            [(cursor_position.row() - start_row) as usize]
 821                            .line;
 822                        let cursor_column = cursor_position.column() as usize;
 823
 824                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 825                        let mut block_width =
 826                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 827                        if block_width == 0.0 {
 828                            block_width = layout.position_map.em_width;
 829                        }
 830                        let block_text = if let CursorShape::Block = selection.cursor_shape {
 831                            layout
 832                                .position_map
 833                                .snapshot
 834                                .chars_at(cursor_position)
 835                                .next()
 836                                .and_then(|(character, _)| {
 837                                    let font_id =
 838                                        cursor_row_layout.font_for_index(cursor_column)?;
 839                                    let text = character.to_string();
 840
 841                                    Some(cx.text_layout_cache().layout_str(
 842                                        &text,
 843                                        cursor_row_layout.font_size(),
 844                                        &[(
 845                                            text.len(),
 846                                            RunStyle {
 847                                                font_id,
 848                                                color: style.background,
 849                                                underline: Default::default(),
 850                                            },
 851                                        )],
 852                                    ))
 853                                })
 854                        } else {
 855                            None
 856                        };
 857
 858                        let x = cursor_character_x - scroll_left;
 859                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 860                            - scroll_top;
 861                        cursors.push(Cursor {
 862                            color: selection_style.cursor,
 863                            block_width,
 864                            origin: vec2f(x, y),
 865                            line_height: layout.position_map.line_height,
 866                            shape: selection.cursor_shape,
 867                            block_text,
 868                        });
 869                    }
 870                }
 871            }
 872        }
 873
 874        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 875            for (ix, line_with_invisibles) in layout.position_map.line_layouts.iter().enumerate() {
 876                let row = start_row + ix as u32;
 877                line_with_invisibles.draw(
 878                    layout,
 879                    row,
 880                    scroll_top,
 881                    scene,
 882                    content_origin,
 883                    scroll_left,
 884                    visible_text_bounds,
 885                    cx,
 886                    &invisible_display_ranges,
 887                    visible_bounds,
 888                )
 889            }
 890        }
 891
 892        scene.paint_layer(Some(bounds), |scene| {
 893            for cursor in cursors {
 894                cursor.paint(scene, content_origin, cx);
 895            }
 896        });
 897
 898        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 899            scene.push_stacking_context(None, None);
 900            let cursor_row_layout =
 901                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
 902            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 903            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
 904            let mut list_origin = content_origin + vec2f(x, y);
 905            let list_width = context_menu.size().x();
 906            let list_height = context_menu.size().y();
 907
 908            // Snap the right edge of the list to the right edge of the window if
 909            // its horizontal bounds overflow.
 910            if list_origin.x() + list_width > cx.window_size().x() {
 911                list_origin.set_x((cx.window_size().x() - list_width).max(0.));
 912            }
 913
 914            if list_origin.y() + list_height > bounds.max_y() {
 915                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
 916            }
 917
 918            context_menu.paint(
 919                scene,
 920                list_origin,
 921                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 922                editor,
 923                cx,
 924            );
 925
 926            scene.pop_stacking_context();
 927        }
 928
 929        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
 930            scene.push_stacking_context(None, None);
 931
 932            // This is safe because we check on layout whether the required row is available
 933            let hovered_row_layout =
 934                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
 935
 936            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
 937            // height. This is the size we will use to decide whether to render popovers above or below
 938            // the hovered line.
 939            let first_size = hover_popovers[0].size();
 940            let height_to_reserve = first_size.y()
 941                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
 942
 943            // Compute Hovered Point
 944            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
 945            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
 946            let hovered_point = content_origin + vec2f(x, y);
 947
 948            if hovered_point.y() - height_to_reserve > 0.0 {
 949                // There is enough space above. Render popovers above the hovered point
 950                let mut current_y = hovered_point.y();
 951                for hover_popover in hover_popovers {
 952                    let size = hover_popover.size();
 953                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
 954
 955                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 956                    if x_out_of_bounds < 0.0 {
 957                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 958                    }
 959
 960                    hover_popover.paint(
 961                        scene,
 962                        popover_origin,
 963                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 964                        editor,
 965                        cx,
 966                    );
 967
 968                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
 969                }
 970            } else {
 971                // There is not enough space above. Render popovers below the hovered point
 972                let mut current_y = hovered_point.y() + layout.position_map.line_height;
 973                for hover_popover in hover_popovers {
 974                    let size = hover_popover.size();
 975                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
 976
 977                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 978                    if x_out_of_bounds < 0.0 {
 979                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 980                    }
 981
 982                    hover_popover.paint(
 983                        scene,
 984                        popover_origin,
 985                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 986                        editor,
 987                        cx,
 988                    );
 989
 990                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
 991                }
 992            }
 993
 994            scene.pop_stacking_context();
 995        }
 996
 997        scene.pop_layer();
 998    }
 999
1000    fn paint_scrollbar(
1001        &mut self,
1002        scene: &mut SceneBuilder,
1003        bounds: RectF,
1004        layout: &mut LayoutState,
1005        cx: &mut ViewContext<Editor>,
1006    ) {
1007        enum ScrollbarMouseHandlers {}
1008        if layout.mode != EditorMode::Full {
1009            return;
1010        }
1011
1012        let style = &self.style.theme.scrollbar;
1013
1014        let top = bounds.min_y();
1015        let bottom = bounds.max_y();
1016        let right = bounds.max_x();
1017        let left = right - style.width;
1018        let row_range = &layout.scrollbar_row_range;
1019        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
1020
1021        let mut height = bounds.height();
1022        let mut first_row_y_offset = 0.0;
1023
1024        // Impose a minimum height on the scrollbar thumb
1025        let row_height = height / max_row;
1026        let min_thumb_height =
1027            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
1028        let thumb_height = (row_range.end - row_range.start) * row_height;
1029        if thumb_height < min_thumb_height {
1030            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
1031            height -= min_thumb_height - thumb_height;
1032        }
1033
1034        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * row_height };
1035
1036        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
1037        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
1038        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
1039        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
1040
1041        if layout.show_scrollbars {
1042            scene.push_quad(Quad {
1043                bounds: track_bounds,
1044                border: style.track.border,
1045                background: style.track.background_color,
1046                ..Default::default()
1047            });
1048
1049            let diff_style = cx.global::<Settings>().theme.editor.diff.clone();
1050            for hunk in layout
1051                .position_map
1052                .snapshot
1053                .buffer_snapshot
1054                .git_diff_hunks_in_range(0..(max_row.floor() as u32), false)
1055            {
1056                let start_y = y_for_row(hunk.buffer_range.start as f32);
1057                let mut end_y = if hunk.buffer_range.start == hunk.buffer_range.end {
1058                    y_for_row((hunk.buffer_range.end + 1) as f32)
1059                } else {
1060                    y_for_row((hunk.buffer_range.end) as f32)
1061                };
1062
1063                if end_y - start_y < 1. {
1064                    end_y = start_y + 1.;
1065                }
1066                let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1067
1068                let color = match hunk.status() {
1069                    DiffHunkStatus::Added => diff_style.inserted,
1070                    DiffHunkStatus::Modified => diff_style.modified,
1071                    DiffHunkStatus::Removed => diff_style.deleted,
1072                };
1073
1074                let border = Border {
1075                    width: 1.,
1076                    color: style.thumb.border.color,
1077                    overlay: false,
1078                    top: false,
1079                    right: true,
1080                    bottom: false,
1081                    left: true,
1082                };
1083
1084                scene.push_quad(Quad {
1085                    bounds,
1086                    background: Some(color),
1087                    border,
1088                    corner_radius: style.thumb.corner_radius,
1089                })
1090            }
1091
1092            scene.push_quad(Quad {
1093                bounds: thumb_bounds,
1094                border: style.thumb.border,
1095                background: style.thumb.background_color,
1096                corner_radius: style.thumb.corner_radius,
1097            });
1098        }
1099
1100        scene.push_cursor_region(CursorRegion {
1101            bounds: track_bounds,
1102            style: CursorStyle::Arrow,
1103        });
1104        scene.push_mouse_region(
1105            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1106                .on_move(move |_, editor: &mut Editor, cx| {
1107                    editor.scroll_manager.show_scrollbar(cx);
1108                })
1109                .on_down(MouseButton::Left, {
1110                    let row_range = row_range.clone();
1111                    move |event, editor: &mut Editor, cx| {
1112                        let y = event.position.y();
1113                        if y < thumb_top || thumb_bottom < y {
1114                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1115                            let top_row = center_row
1116                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1117                            let mut position = editor.scroll_position(cx);
1118                            position.set_y(top_row as f32);
1119                            editor.set_scroll_position(position, cx);
1120                        } else {
1121                            editor.scroll_manager.show_scrollbar(cx);
1122                        }
1123                    }
1124                })
1125                .on_drag(MouseButton::Left, {
1126                    move |event, editor: &mut Editor, cx| {
1127                        let y = event.prev_mouse_position.y();
1128                        let new_y = event.position.y();
1129                        if thumb_top < y && y < thumb_bottom {
1130                            let mut position = editor.scroll_position(cx);
1131                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1132                            if position.y() < 0.0 {
1133                                position.set_y(0.);
1134                            }
1135                            editor.set_scroll_position(position, cx);
1136                        }
1137                    }
1138                }),
1139        );
1140    }
1141
1142    #[allow(clippy::too_many_arguments)]
1143    fn paint_highlighted_range(
1144        &self,
1145        scene: &mut SceneBuilder,
1146        range: Range<DisplayPoint>,
1147        color: Color,
1148        corner_radius: f32,
1149        line_end_overshoot: f32,
1150        layout: &LayoutState,
1151        content_origin: Vector2F,
1152        scroll_top: f32,
1153        scroll_left: f32,
1154        bounds: RectF,
1155    ) {
1156        let start_row = layout.visible_display_row_range.start;
1157        let end_row = layout.visible_display_row_range.end;
1158        if range.start != range.end {
1159            let row_range = if range.end.column() == 0 {
1160                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1161            } else {
1162                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1163            };
1164
1165            let highlighted_range = HighlightedRange {
1166                color,
1167                line_height: layout.position_map.line_height,
1168                corner_radius,
1169                start_y: content_origin.y()
1170                    + row_range.start as f32 * layout.position_map.line_height
1171                    - scroll_top,
1172                lines: row_range
1173                    .into_iter()
1174                    .map(|row| {
1175                        let line_layout =
1176                            &layout.position_map.line_layouts[(row - start_row) as usize].line;
1177                        HighlightedRangeLine {
1178                            start_x: if row == range.start.row() {
1179                                content_origin.x()
1180                                    + line_layout.x_for_index(range.start.column() as usize)
1181                                    - scroll_left
1182                            } else {
1183                                content_origin.x() - scroll_left
1184                            },
1185                            end_x: if row == range.end.row() {
1186                                content_origin.x()
1187                                    + line_layout.x_for_index(range.end.column() as usize)
1188                                    - scroll_left
1189                            } else {
1190                                content_origin.x() + line_layout.width() + line_end_overshoot
1191                                    - scroll_left
1192                            },
1193                        }
1194                    })
1195                    .collect(),
1196            };
1197
1198            highlighted_range.paint(bounds, scene);
1199        }
1200    }
1201
1202    fn paint_blocks(
1203        &mut self,
1204        scene: &mut SceneBuilder,
1205        bounds: RectF,
1206        visible_bounds: RectF,
1207        layout: &mut LayoutState,
1208        editor: &mut Editor,
1209        cx: &mut ViewContext<Editor>,
1210    ) {
1211        let scroll_position = layout.position_map.snapshot.scroll_position();
1212        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1213        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1214
1215        for block in &mut layout.blocks {
1216            let mut origin = bounds.origin()
1217                + vec2f(
1218                    0.,
1219                    block.row as f32 * layout.position_map.line_height - scroll_top,
1220                );
1221            if !matches!(block.style, BlockStyle::Sticky) {
1222                origin += vec2f(-scroll_left, 0.);
1223            }
1224            block
1225                .element
1226                .paint(scene, origin, visible_bounds, editor, cx);
1227        }
1228    }
1229
1230    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1231        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1232        let style = &self.style;
1233
1234        cx.text_layout_cache()
1235            .layout_str(
1236                "1".repeat(digit_count).as_str(),
1237                style.text.font_size,
1238                &[(
1239                    digit_count,
1240                    RunStyle {
1241                        font_id: style.text.font_id,
1242                        color: Color::black(),
1243                        underline: Default::default(),
1244                    },
1245                )],
1246            )
1247            .width()
1248    }
1249
1250    //Folds contained in a hunk are ignored apart from shrinking visual size
1251    //If a fold contains any hunks then that fold line is marked as modified
1252    fn layout_git_gutters(
1253        &self,
1254        display_rows: Range<u32>,
1255        snapshot: &EditorSnapshot,
1256    ) -> Vec<DisplayDiffHunk> {
1257        let buffer_snapshot = &snapshot.buffer_snapshot;
1258
1259        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1260            .to_point(snapshot)
1261            .row;
1262        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1263            .to_point(snapshot)
1264            .row;
1265
1266        buffer_snapshot
1267            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row, false)
1268            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1269            .dedup()
1270            .collect()
1271    }
1272
1273    fn layout_line_numbers(
1274        &self,
1275        rows: Range<u32>,
1276        active_rows: &BTreeMap<u32, bool>,
1277        is_singleton: bool,
1278        snapshot: &EditorSnapshot,
1279        cx: &ViewContext<Editor>,
1280    ) -> (
1281        Vec<Option<text_layout::Line>>,
1282        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1283    ) {
1284        let style = &self.style;
1285        let include_line_numbers = snapshot.mode == EditorMode::Full;
1286        let mut line_number_layouts = Vec::with_capacity(rows.len());
1287        let mut fold_statuses = Vec::with_capacity(rows.len());
1288        let mut line_number = String::new();
1289        for (ix, row) in snapshot
1290            .buffer_rows(rows.start)
1291            .take((rows.end - rows.start) as usize)
1292            .enumerate()
1293        {
1294            let display_row = rows.start + ix as u32;
1295            let (active, color) = if active_rows.contains_key(&display_row) {
1296                (true, style.line_number_active)
1297            } else {
1298                (false, style.line_number)
1299            };
1300            if let Some(buffer_row) = row {
1301                if include_line_numbers {
1302                    line_number.clear();
1303                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1304                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1305                        &line_number,
1306                        style.text.font_size,
1307                        &[(
1308                            line_number.len(),
1309                            RunStyle {
1310                                font_id: style.text.font_id,
1311                                color,
1312                                underline: Default::default(),
1313                            },
1314                        )],
1315                    )));
1316                    fold_statuses.push(
1317                        is_singleton
1318                            .then(|| {
1319                                snapshot
1320                                    .fold_for_line(buffer_row)
1321                                    .map(|fold_status| (fold_status, buffer_row, active))
1322                            })
1323                            .flatten(),
1324                    )
1325                }
1326            } else {
1327                fold_statuses.push(None);
1328                line_number_layouts.push(None);
1329            }
1330        }
1331
1332        (line_number_layouts, fold_statuses)
1333    }
1334
1335    fn layout_lines(
1336        &mut self,
1337        rows: Range<u32>,
1338        line_number_layouts: &[Option<Line>],
1339        snapshot: &EditorSnapshot,
1340        cx: &ViewContext<Editor>,
1341    ) -> Vec<LineWithInvisibles> {
1342        if rows.start >= rows.end {
1343            return Vec::new();
1344        }
1345
1346        // When the editor is empty and unfocused, then show the placeholder.
1347        if snapshot.is_empty() {
1348            let placeholder_style = self
1349                .style
1350                .placeholder_text
1351                .as_ref()
1352                .unwrap_or(&self.style.text);
1353            let placeholder_text = snapshot.placeholder_text();
1354            let placeholder_lines = placeholder_text
1355                .as_ref()
1356                .map_or("", AsRef::as_ref)
1357                .split('\n')
1358                .skip(rows.start as usize)
1359                .chain(iter::repeat(""))
1360                .take(rows.len());
1361            placeholder_lines
1362                .map(|line| {
1363                    cx.text_layout_cache().layout_str(
1364                        line,
1365                        placeholder_style.font_size,
1366                        &[(
1367                            line.len(),
1368                            RunStyle {
1369                                font_id: placeholder_style.font_id,
1370                                color: placeholder_style.color,
1371                                underline: Default::default(),
1372                            },
1373                        )],
1374                    )
1375                })
1376                .map(|line| LineWithInvisibles {
1377                    line,
1378                    invisibles: Vec::new(),
1379                })
1380                .collect()
1381        } else {
1382            let style = &self.style;
1383            let chunks = snapshot
1384                .chunks(rows.clone(), true, Some(style.theme.suggestion))
1385                .map(|chunk| {
1386                    let mut highlight_style = chunk
1387                        .syntax_highlight_id
1388                        .and_then(|id| id.style(&style.syntax));
1389
1390                    if let Some(chunk_highlight) = chunk.highlight_style {
1391                        if let Some(highlight_style) = highlight_style.as_mut() {
1392                            highlight_style.highlight(chunk_highlight);
1393                        } else {
1394                            highlight_style = Some(chunk_highlight);
1395                        }
1396                    }
1397
1398                    let mut diagnostic_highlight = HighlightStyle::default();
1399
1400                    if chunk.is_unnecessary {
1401                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1402                    }
1403
1404                    if let Some(severity) = chunk.diagnostic_severity {
1405                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1406                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1407                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1408                            diagnostic_highlight.underline = Some(Underline {
1409                                color: Some(diagnostic_style.message.text.color),
1410                                thickness: 1.0.into(),
1411                                squiggly: true,
1412                            });
1413                        }
1414                    }
1415
1416                    if let Some(highlight_style) = highlight_style.as_mut() {
1417                        highlight_style.highlight(diagnostic_highlight);
1418                    } else {
1419                        highlight_style = Some(diagnostic_highlight);
1420                    }
1421
1422                    HighlightedChunk {
1423                        chunk: chunk.text,
1424                        style: highlight_style,
1425                        is_tab: chunk.is_tab,
1426                    }
1427                });
1428
1429            LineWithInvisibles::from_chunks(
1430                chunks,
1431                &style.text,
1432                cx.text_layout_cache(),
1433                cx.font_cache(),
1434                MAX_LINE_LEN,
1435                rows.len() as usize,
1436                line_number_layouts,
1437                snapshot.mode,
1438            )
1439        }
1440    }
1441
1442    #[allow(clippy::too_many_arguments)]
1443    fn layout_blocks(
1444        &mut self,
1445        rows: Range<u32>,
1446        snapshot: &EditorSnapshot,
1447        editor_width: f32,
1448        scroll_width: f32,
1449        gutter_padding: f32,
1450        gutter_width: f32,
1451        em_width: f32,
1452        text_x: f32,
1453        line_height: f32,
1454        style: &EditorStyle,
1455        line_layouts: &[LineWithInvisibles],
1456        include_root: bool,
1457        editor: &mut Editor,
1458        cx: &mut LayoutContext<Editor>,
1459    ) -> (f32, Vec<BlockLayout>) {
1460        let tooltip_style = cx.global::<Settings>().theme.tooltip.clone();
1461        let scroll_x = snapshot.scroll_anchor.offset.x();
1462        let (fixed_blocks, non_fixed_blocks) = snapshot
1463            .blocks_in_range(rows.clone())
1464            .partition::<Vec<_>, _>(|(_, block)| match block {
1465                TransformBlock::ExcerptHeader { .. } => false,
1466                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1467            });
1468        let mut render_block = |block: &TransformBlock, width: f32| {
1469            let mut element = match block {
1470                TransformBlock::Custom(block) => {
1471                    let align_to = block
1472                        .position()
1473                        .to_point(&snapshot.buffer_snapshot)
1474                        .to_display_point(snapshot);
1475                    let anchor_x = text_x
1476                        + if rows.contains(&align_to.row()) {
1477                            line_layouts[(align_to.row() - rows.start) as usize]
1478                                .line
1479                                .x_for_index(align_to.column() as usize)
1480                        } else {
1481                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1482                                .x_for_index(align_to.column() as usize)
1483                        };
1484
1485                    block.render(&mut BlockContext {
1486                        view_context: cx,
1487                        anchor_x,
1488                        gutter_padding,
1489                        line_height,
1490                        scroll_x,
1491                        gutter_width,
1492                        em_width,
1493                    })
1494                }
1495                TransformBlock::ExcerptHeader {
1496                    id,
1497                    buffer,
1498                    range,
1499                    starts_new_buffer,
1500                    ..
1501                } => {
1502                    let id = *id;
1503                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1504                        let jump_path = ProjectPath {
1505                            worktree_id: file.worktree_id(cx),
1506                            path: file.path.clone(),
1507                        };
1508                        let jump_anchor = range
1509                            .primary
1510                            .as_ref()
1511                            .map_or(range.context.start, |primary| primary.start);
1512                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1513
1514                        enum JumpIcon {}
1515                        MouseEventHandler::<JumpIcon, _>::new(id.into(), cx, |state, _| {
1516                            let style = style.jump_icon.style_for(state, false);
1517                            Svg::new("icons/arrow_up_right_8.svg")
1518                                .with_color(style.color)
1519                                .constrained()
1520                                .with_width(style.icon_width)
1521                                .aligned()
1522                                .contained()
1523                                .with_style(style.container)
1524                                .constrained()
1525                                .with_width(style.button_width)
1526                                .with_height(style.button_width)
1527                        })
1528                        .with_cursor_style(CursorStyle::PointingHand)
1529                        .on_click(MouseButton::Left, move |_, editor, cx| {
1530                            if let Some(workspace) = editor
1531                                .workspace
1532                                .as_ref()
1533                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1534                            {
1535                                workspace.update(cx, |workspace, cx| {
1536                                    Editor::jump(
1537                                        workspace,
1538                                        jump_path.clone(),
1539                                        jump_position,
1540                                        jump_anchor,
1541                                        cx,
1542                                    );
1543                                });
1544                            }
1545                        })
1546                        .with_tooltip::<JumpIcon>(
1547                            id.into(),
1548                            "Jump to Buffer".to_string(),
1549                            Some(Box::new(crate::OpenExcerpts)),
1550                            tooltip_style.clone(),
1551                            cx,
1552                        )
1553                        .aligned()
1554                        .flex_float()
1555                    });
1556
1557                    if *starts_new_buffer {
1558                        let style = &self.style.diagnostic_path_header;
1559                        let font_size =
1560                            (style.text_scale_factor * self.style.text.font_size).round();
1561
1562                        let path = buffer.resolve_file_path(cx, include_root);
1563                        let mut filename = None;
1564                        let mut parent_path = None;
1565                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1566                        if let Some(path) = path {
1567                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1568                            parent_path =
1569                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1570                        }
1571
1572                        Flex::row()
1573                            .with_child(
1574                                Label::new(
1575                                    filename.unwrap_or_else(|| "untitled".to_string()),
1576                                    style.filename.text.clone().with_font_size(font_size),
1577                                )
1578                                .contained()
1579                                .with_style(style.filename.container)
1580                                .aligned(),
1581                            )
1582                            .with_children(parent_path.map(|path| {
1583                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1584                                    .contained()
1585                                    .with_style(style.path.container)
1586                                    .aligned()
1587                            }))
1588                            .with_children(jump_icon)
1589                            .contained()
1590                            .with_style(style.container)
1591                            .with_padding_left(gutter_padding)
1592                            .with_padding_right(gutter_padding)
1593                            .expanded()
1594                            .into_any_named("path header block")
1595                    } else {
1596                        let text_style = self.style.text.clone();
1597                        Flex::row()
1598                            .with_child(Label::new("⋯", text_style))
1599                            .with_children(jump_icon)
1600                            .contained()
1601                            .with_padding_left(gutter_padding)
1602                            .with_padding_right(gutter_padding)
1603                            .expanded()
1604                            .into_any_named("collapsed context")
1605                    }
1606                }
1607            };
1608
1609            element.layout(
1610                SizeConstraint {
1611                    min: Vector2F::zero(),
1612                    max: vec2f(width, block.height() as f32 * line_height),
1613                },
1614                editor,
1615                cx,
1616            );
1617            element
1618        };
1619
1620        let mut fixed_block_max_width = 0f32;
1621        let mut blocks = Vec::new();
1622        for (row, block) in fixed_blocks {
1623            let element = render_block(block, f32::INFINITY);
1624            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1625            blocks.push(BlockLayout {
1626                row,
1627                element,
1628                style: BlockStyle::Fixed,
1629            });
1630        }
1631        for (row, block) in non_fixed_blocks {
1632            let style = match block {
1633                TransformBlock::Custom(block) => block.style(),
1634                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1635            };
1636            let width = match style {
1637                BlockStyle::Sticky => editor_width,
1638                BlockStyle::Flex => editor_width
1639                    .max(fixed_block_max_width)
1640                    .max(gutter_width + scroll_width),
1641                BlockStyle::Fixed => unreachable!(),
1642            };
1643            let element = render_block(block, width);
1644            blocks.push(BlockLayout {
1645                row,
1646                element,
1647                style,
1648            });
1649        }
1650        (
1651            scroll_width.max(fixed_block_max_width - gutter_width),
1652            blocks,
1653        )
1654    }
1655}
1656
1657struct HighlightedChunk<'a> {
1658    chunk: &'a str,
1659    style: Option<HighlightStyle>,
1660    is_tab: bool,
1661}
1662
1663#[derive(Debug)]
1664pub struct LineWithInvisibles {
1665    pub line: Line,
1666    invisibles: Vec<Invisible>,
1667}
1668
1669impl LineWithInvisibles {
1670    fn from_chunks<'a>(
1671        chunks: impl Iterator<Item = HighlightedChunk<'a>>,
1672        text_style: &TextStyle,
1673        text_layout_cache: &TextLayoutCache,
1674        font_cache: &Arc<FontCache>,
1675        max_line_len: usize,
1676        max_line_count: usize,
1677        line_number_layouts: &[Option<Line>],
1678        editor_mode: EditorMode,
1679    ) -> Vec<Self> {
1680        let mut layouts = Vec::with_capacity(max_line_count);
1681        let mut line = String::new();
1682        let mut invisibles = Vec::new();
1683        let mut styles = Vec::new();
1684        let mut non_whitespace_added = false;
1685        let mut row = 0;
1686        let mut line_exceeded_max_len = false;
1687        for highlighted_chunk in chunks.chain([HighlightedChunk {
1688            chunk: "\n",
1689            style: None,
1690            is_tab: false,
1691        }]) {
1692            for (ix, mut line_chunk) in highlighted_chunk.chunk.split('\n').enumerate() {
1693                if ix > 0 {
1694                    layouts.push(Self {
1695                        line: text_layout_cache.layout_str(&line, text_style.font_size, &styles),
1696                        invisibles: invisibles.drain(..).collect(),
1697                    });
1698
1699                    line.clear();
1700                    styles.clear();
1701                    row += 1;
1702                    line_exceeded_max_len = false;
1703                    non_whitespace_added = false;
1704                    if row == max_line_count {
1705                        return layouts;
1706                    }
1707                }
1708
1709                if !line_chunk.is_empty() && !line_exceeded_max_len {
1710                    let text_style = if let Some(style) = highlighted_chunk.style {
1711                        text_style
1712                            .clone()
1713                            .highlight(style, font_cache)
1714                            .map(Cow::Owned)
1715                            .unwrap_or_else(|_| Cow::Borrowed(text_style))
1716                    } else {
1717                        Cow::Borrowed(text_style)
1718                    };
1719
1720                    if line.len() + line_chunk.len() > max_line_len {
1721                        let mut chunk_len = max_line_len - line.len();
1722                        while !line_chunk.is_char_boundary(chunk_len) {
1723                            chunk_len -= 1;
1724                        }
1725                        line_chunk = &line_chunk[..chunk_len];
1726                        line_exceeded_max_len = true;
1727                    }
1728
1729                    styles.push((
1730                        line_chunk.len(),
1731                        RunStyle {
1732                            font_id: text_style.font_id,
1733                            color: text_style.color,
1734                            underline: text_style.underline,
1735                        },
1736                    ));
1737
1738                    if editor_mode == EditorMode::Full {
1739                        // Line wrap pads its contents with fake whitespaces,
1740                        // avoid printing them
1741                        let inside_wrapped_string = line_number_layouts
1742                            .get(row)
1743                            .and_then(|layout| layout.as_ref())
1744                            .is_none();
1745                        if highlighted_chunk.is_tab {
1746                            if non_whitespace_added || !inside_wrapped_string {
1747                                invisibles.push(Invisible::Tab {
1748                                    line_start_offset: line.len(),
1749                                });
1750                            }
1751                        } else {
1752                            invisibles.extend(
1753                                line_chunk
1754                                    .chars()
1755                                    .enumerate()
1756                                    .filter(|(_, line_char)| {
1757                                        let is_whitespace = line_char.is_whitespace();
1758                                        non_whitespace_added |= !is_whitespace;
1759                                        is_whitespace
1760                                            && (non_whitespace_added || !inside_wrapped_string)
1761                                    })
1762                                    .map(|(whitespace_index, _)| Invisible::Whitespace {
1763                                        line_offset: line.len() + whitespace_index,
1764                                    }),
1765                            )
1766                        }
1767                    }
1768
1769                    line.push_str(line_chunk);
1770                }
1771            }
1772        }
1773
1774        layouts
1775    }
1776
1777    fn draw(
1778        &self,
1779        layout: &LayoutState,
1780        row: u32,
1781        scroll_top: f32,
1782        scene: &mut SceneBuilder,
1783        content_origin: Vector2F,
1784        scroll_left: f32,
1785        visible_text_bounds: RectF,
1786        cx: &mut ViewContext<Editor>,
1787        selection_ranges: &[Range<DisplayPoint>],
1788        visible_bounds: RectF,
1789    ) {
1790        let line_height = layout.position_map.line_height;
1791        let line_y = row as f32 * line_height - scroll_top;
1792
1793        self.line.paint(
1794            scene,
1795            content_origin + vec2f(-scroll_left, line_y),
1796            visible_text_bounds,
1797            line_height,
1798            cx,
1799        );
1800
1801        self.draw_invisibles(
1802            cx,
1803            &selection_ranges,
1804            layout,
1805            content_origin,
1806            scroll_left,
1807            line_y,
1808            row,
1809            scene,
1810            visible_bounds,
1811            line_height,
1812        );
1813    }
1814
1815    fn draw_invisibles(
1816        &self,
1817        cx: &mut ViewContext<Editor>,
1818        selection_ranges: &[Range<DisplayPoint>],
1819        layout: &LayoutState,
1820        content_origin: Vector2F,
1821        scroll_left: f32,
1822        line_y: f32,
1823        row: u32,
1824        scene: &mut SceneBuilder,
1825        visible_bounds: RectF,
1826        line_height: f32,
1827    ) {
1828        let settings = cx.global::<Settings>();
1829        let allowed_invisibles_regions = match settings
1830            .editor_overrides
1831            .show_whitespaces
1832            .or(settings.editor_defaults.show_whitespaces)
1833            .unwrap_or_default()
1834        {
1835            ShowWhitespaces::None => return,
1836            ShowWhitespaces::Selection => Some(selection_ranges),
1837            ShowWhitespaces::All => None,
1838        };
1839
1840        for invisible in &self.invisibles {
1841            let (&token_offset, invisible_symbol) = match invisible {
1842                Invisible::Tab { line_start_offset } => (line_start_offset, &layout.tab_invisible),
1843                Invisible::Whitespace { line_offset } => (line_offset, &layout.space_invisible),
1844            };
1845
1846            let x_offset = self.line.x_for_index(token_offset);
1847            let invisible_offset =
1848                (layout.position_map.em_width - invisible_symbol.width()).max(0.0) / 2.0;
1849            let origin = content_origin + vec2f(-scroll_left + x_offset + invisible_offset, line_y);
1850
1851            if let Some(allowed_regions) = allowed_invisibles_regions {
1852                let invisible_point = DisplayPoint::new(row, token_offset as u32);
1853                if !allowed_regions
1854                    .iter()
1855                    .any(|region| region.start <= invisible_point && invisible_point < region.end)
1856                {
1857                    continue;
1858                }
1859            }
1860            invisible_symbol.paint(scene, origin, visible_bounds, line_height, cx);
1861        }
1862    }
1863}
1864
1865#[derive(Debug, Clone, Copy, PartialEq, Eq)]
1866enum Invisible {
1867    Tab { line_start_offset: usize },
1868    Whitespace { line_offset: usize },
1869}
1870
1871impl Element<Editor> for EditorElement {
1872    type LayoutState = LayoutState;
1873    type PaintState = ();
1874
1875    fn layout(
1876        &mut self,
1877        constraint: SizeConstraint,
1878        editor: &mut Editor,
1879        cx: &mut LayoutContext<Editor>,
1880    ) -> (Vector2F, Self::LayoutState) {
1881        let mut size = constraint.max;
1882        if size.x().is_infinite() {
1883            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1884        }
1885
1886        let snapshot = editor.snapshot(cx);
1887        let style = self.style.clone();
1888        let line_height = style.text.line_height(cx.font_cache());
1889
1890        let gutter_padding;
1891        let gutter_width;
1892        let gutter_margin;
1893        if snapshot.mode == EditorMode::Full {
1894            let em_width = style.text.em_width(cx.font_cache());
1895            gutter_padding = (em_width * style.gutter_padding_factor).round();
1896            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1897            gutter_margin = -style.text.descent(cx.font_cache());
1898        } else {
1899            gutter_padding = 0.0;
1900            gutter_width = 0.0;
1901            gutter_margin = 0.0;
1902        };
1903
1904        let text_width = size.x() - gutter_width;
1905        let em_width = style.text.em_width(cx.font_cache());
1906        let em_advance = style.text.em_advance(cx.font_cache());
1907        let overscroll = vec2f(em_width, 0.);
1908        let snapshot = {
1909            editor.set_visible_line_count(size.y() / line_height);
1910
1911            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
1912            let wrap_width = match editor.soft_wrap_mode(cx) {
1913                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
1914                SoftWrap::EditorWidth => editor_width,
1915                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
1916            };
1917
1918            if editor.set_wrap_width(Some(wrap_width), cx) {
1919                editor.snapshot(cx)
1920            } else {
1921                snapshot
1922            }
1923        };
1924
1925        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1926        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1927            size.set_y(
1928                scroll_height
1929                    .min(constraint.max_along(Axis::Vertical))
1930                    .max(constraint.min_along(Axis::Vertical))
1931                    .min(line_height * max_lines as f32),
1932            )
1933        } else if let EditorMode::SingleLine = snapshot.mode {
1934            size.set_y(
1935                line_height
1936                    .min(constraint.max_along(Axis::Vertical))
1937                    .max(constraint.min_along(Axis::Vertical)),
1938            )
1939        } else if size.y().is_infinite() {
1940            size.set_y(scroll_height);
1941        }
1942        let gutter_size = vec2f(gutter_width, size.y());
1943        let text_size = vec2f(text_width, size.y());
1944
1945        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
1946        let mut snapshot = editor.snapshot(cx);
1947
1948        let scroll_position = snapshot.scroll_position();
1949        // The scroll position is a fractional point, the whole number of which represents
1950        // the top of the window in terms of display rows.
1951        let start_row = scroll_position.y() as u32;
1952        let height_in_lines = size.y() / line_height;
1953        let max_row = snapshot.max_point().row();
1954
1955        // Add 1 to ensure selections bleed off screen
1956        let end_row = 1 + cmp::min(
1957            (scroll_position.y() + height_in_lines).ceil() as u32,
1958            max_row,
1959        );
1960
1961        let start_anchor = if start_row == 0 {
1962            Anchor::min()
1963        } else {
1964            snapshot
1965                .buffer_snapshot
1966                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
1967        };
1968        let end_anchor = if end_row > max_row {
1969            Anchor::max()
1970        } else {
1971            snapshot
1972                .buffer_snapshot
1973                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
1974        };
1975
1976        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
1977        let mut active_rows = BTreeMap::new();
1978        let mut fold_ranges = Vec::new();
1979        let is_singleton = editor.is_singleton(cx);
1980
1981        let highlighted_rows = editor.highlighted_rows();
1982        let theme = cx.global::<Settings>().theme.as_ref();
1983        let highlighted_ranges = editor.background_highlights_in_range(
1984            start_anchor..end_anchor,
1985            &snapshot.display_snapshot,
1986            theme,
1987        );
1988
1989        fold_ranges.extend(
1990            snapshot
1991                .folds_in_range(start_anchor..end_anchor)
1992                .map(|anchor| {
1993                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
1994                    (
1995                        start.row,
1996                        start.to_display_point(&snapshot.display_snapshot)
1997                            ..anchor.end.to_display_point(&snapshot),
1998                    )
1999                }),
2000        );
2001
2002        let mut remote_selections = HashMap::default();
2003        for (replica_id, line_mode, cursor_shape, selection) in snapshot
2004            .buffer_snapshot
2005            .remote_selections_in_range(&(start_anchor..end_anchor))
2006        {
2007            // The local selections match the leader's selections.
2008            if Some(replica_id) == editor.leader_replica_id {
2009                continue;
2010            }
2011            remote_selections
2012                .entry(replica_id)
2013                .or_insert(Vec::new())
2014                .push(SelectionLayout::new(
2015                    selection,
2016                    line_mode,
2017                    cursor_shape,
2018                    &snapshot.display_snapshot,
2019                ));
2020        }
2021        selections.extend(remote_selections);
2022
2023        if editor.show_local_selections {
2024            let mut local_selections = editor
2025                .selections
2026                .disjoint_in_range(start_anchor..end_anchor, cx);
2027            local_selections.extend(editor.selections.pending(cx));
2028            for selection in &local_selections {
2029                let is_empty = selection.start == selection.end;
2030                let selection_start = snapshot.prev_line_boundary(selection.start).1;
2031                let selection_end = snapshot.next_line_boundary(selection.end).1;
2032                for row in cmp::max(selection_start.row(), start_row)
2033                    ..=cmp::min(selection_end.row(), end_row)
2034                {
2035                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
2036                    *contains_non_empty_selection |= !is_empty;
2037                }
2038            }
2039
2040            // Render the local selections in the leader's color when following.
2041            let local_replica_id = editor
2042                .leader_replica_id
2043                .unwrap_or_else(|| editor.replica_id(cx));
2044
2045            selections.push((
2046                local_replica_id,
2047                local_selections
2048                    .into_iter()
2049                    .map(|selection| {
2050                        SelectionLayout::new(
2051                            selection,
2052                            editor.selections.line_mode,
2053                            editor.cursor_shape,
2054                            &snapshot.display_snapshot,
2055                        )
2056                    })
2057                    .collect(),
2058            ));
2059        }
2060
2061        let show_scrollbars = editor.scroll_manager.scrollbars_visible();
2062        let include_root = editor
2063            .project
2064            .as_ref()
2065            .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
2066            .unwrap_or_default();
2067
2068        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
2069            .into_iter()
2070            .map(|(id, fold)| {
2071                let color = self
2072                    .style
2073                    .folds
2074                    .ellipses
2075                    .background
2076                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize), false)
2077                    .color;
2078
2079                (id, fold, color)
2080            })
2081            .collect();
2082
2083        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
2084            start_row..end_row,
2085            &active_rows,
2086            is_singleton,
2087            &snapshot,
2088            cx,
2089        );
2090
2091        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
2092
2093        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
2094
2095        let mut max_visible_line_width = 0.0;
2096        let line_layouts =
2097            self.layout_lines(start_row..end_row, &line_number_layouts, &snapshot, cx);
2098        for line_with_invisibles in &line_layouts {
2099            if line_with_invisibles.line.width() > max_visible_line_width {
2100                max_visible_line_width = line_with_invisibles.line.width();
2101            }
2102        }
2103
2104        let style = self.style.clone();
2105        let longest_line_width = layout_line(
2106            snapshot.longest_row(),
2107            &snapshot,
2108            &style,
2109            cx.text_layout_cache(),
2110        )
2111        .width();
2112        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
2113        let em_width = style.text.em_width(cx.font_cache());
2114        let (scroll_width, blocks) = self.layout_blocks(
2115            start_row..end_row,
2116            &snapshot,
2117            size.x(),
2118            scroll_width,
2119            gutter_padding,
2120            gutter_width,
2121            em_width,
2122            gutter_width + gutter_margin,
2123            line_height,
2124            &style,
2125            &line_layouts,
2126            include_root,
2127            editor,
2128            cx,
2129        );
2130
2131        let scroll_max = vec2f(
2132            ((scroll_width - text_size.x()) / em_width).max(0.0),
2133            max_row as f32,
2134        );
2135
2136        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
2137
2138        let autoscrolled = if autoscroll_horizontally {
2139            editor.autoscroll_horizontally(
2140                start_row,
2141                text_size.x(),
2142                scroll_width,
2143                em_width,
2144                &line_layouts,
2145                cx,
2146            )
2147        } else {
2148            false
2149        };
2150
2151        if clamped || autoscrolled {
2152            snapshot = editor.snapshot(cx);
2153        }
2154
2155        let newest_selection_head = editor
2156            .selections
2157            .newest::<usize>(cx)
2158            .head()
2159            .to_display_point(&snapshot);
2160        let style = editor.style(cx);
2161
2162        let mut context_menu = None;
2163        let mut code_actions_indicator = None;
2164        if (start_row..end_row).contains(&newest_selection_head.row()) {
2165            if editor.context_menu_visible() {
2166                context_menu = editor.render_context_menu(newest_selection_head, style.clone(), cx);
2167            }
2168
2169            let active = matches!(
2170                editor.context_menu,
2171                Some(crate::ContextMenu::CodeActions(_))
2172            );
2173
2174            code_actions_indicator = editor
2175                .render_code_actions_indicator(&style, active, cx)
2176                .map(|indicator| (newest_selection_head.row(), indicator));
2177        }
2178
2179        let visible_rows = start_row..start_row + line_layouts.len() as u32;
2180        let mut hover = editor
2181            .hover_state
2182            .render(&snapshot, &style, visible_rows, cx);
2183        let mode = editor.mode;
2184
2185        let mut fold_indicators = editor.render_fold_indicators(
2186            fold_statuses,
2187            &style,
2188            editor.gutter_hovered,
2189            line_height,
2190            gutter_margin,
2191            cx,
2192        );
2193
2194        if let Some((_, context_menu)) = context_menu.as_mut() {
2195            context_menu.layout(
2196                SizeConstraint {
2197                    min: Vector2F::zero(),
2198                    max: vec2f(
2199                        cx.window_size().x() * 0.7,
2200                        (12. * line_height).min((size.y() - line_height) / 2.),
2201                    ),
2202                },
2203                editor,
2204                cx,
2205            );
2206        }
2207
2208        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
2209            indicator.layout(
2210                SizeConstraint::strict_along(
2211                    Axis::Vertical,
2212                    line_height * style.code_actions.vertical_scale,
2213                ),
2214                editor,
2215                cx,
2216            );
2217        }
2218
2219        for fold_indicator in fold_indicators.iter_mut() {
2220            if let Some(indicator) = fold_indicator.as_mut() {
2221                indicator.layout(
2222                    SizeConstraint::strict_along(
2223                        Axis::Vertical,
2224                        line_height * style.code_actions.vertical_scale,
2225                    ),
2226                    editor,
2227                    cx,
2228                );
2229            }
2230        }
2231
2232        if let Some((_, hover_popovers)) = hover.as_mut() {
2233            for hover_popover in hover_popovers.iter_mut() {
2234                hover_popover.layout(
2235                    SizeConstraint {
2236                        min: Vector2F::zero(),
2237                        max: vec2f(
2238                            (120. * em_width) // Default size
2239                                .min(size.x() / 2.) // Shrink to half of the editor width
2240                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
2241                            (16. * line_height) // Default size
2242                                .min(size.y() / 2.) // Shrink to half of the editor height
2243                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
2244                        ),
2245                    },
2246                    editor,
2247                    cx,
2248                );
2249            }
2250        }
2251
2252        let invisible_symbol_font_size = self.style.text.font_size / 2.0;
2253        let invisible_symbol_style = RunStyle {
2254            color: self.style.whitespace,
2255            font_id: self.style.text.font_id,
2256            underline: Default::default(),
2257        };
2258
2259        (
2260            size,
2261            LayoutState {
2262                mode,
2263                position_map: Arc::new(PositionMap {
2264                    size,
2265                    scroll_max,
2266                    line_layouts,
2267                    line_height,
2268                    em_width,
2269                    em_advance,
2270                    snapshot,
2271                }),
2272                visible_display_row_range: start_row..end_row,
2273                gutter_size,
2274                gutter_padding,
2275                text_size,
2276                scrollbar_row_range,
2277                show_scrollbars,
2278                max_row,
2279                gutter_margin,
2280                active_rows,
2281                highlighted_rows,
2282                highlighted_ranges,
2283                fold_ranges,
2284                line_number_layouts,
2285                display_hunks,
2286                blocks,
2287                selections,
2288                context_menu,
2289                code_actions_indicator,
2290                fold_indicators,
2291                tab_invisible: cx.text_layout_cache().layout_str(
2292                    "→",
2293                    invisible_symbol_font_size,
2294                    &[("→".len(), invisible_symbol_style)],
2295                ),
2296                space_invisible: cx.text_layout_cache().layout_str(
2297                    "•",
2298                    invisible_symbol_font_size,
2299                    &[("•".len(), invisible_symbol_style)],
2300                ),
2301                hover_popovers: hover,
2302            },
2303        )
2304    }
2305
2306    fn paint(
2307        &mut self,
2308        scene: &mut SceneBuilder,
2309        bounds: RectF,
2310        visible_bounds: RectF,
2311        layout: &mut Self::LayoutState,
2312        editor: &mut Editor,
2313        cx: &mut ViewContext<Editor>,
2314    ) -> Self::PaintState {
2315        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2316        scene.push_layer(Some(visible_bounds));
2317
2318        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2319        let text_bounds = RectF::new(
2320            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2321            layout.text_size,
2322        );
2323
2324        Self::attach_mouse_handlers(
2325            scene,
2326            &layout.position_map,
2327            layout.hover_popovers.is_some(),
2328            visible_bounds,
2329            text_bounds,
2330            gutter_bounds,
2331            bounds,
2332            cx,
2333        );
2334
2335        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2336        if layout.gutter_size.x() > 0. {
2337            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2338        }
2339        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2340
2341        scene.push_layer(Some(bounds));
2342        if !layout.blocks.is_empty() {
2343            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2344        }
2345        self.paint_scrollbar(scene, bounds, layout, cx);
2346        scene.pop_layer();
2347
2348        scene.pop_layer();
2349    }
2350
2351    fn rect_for_text_range(
2352        &self,
2353        range_utf16: Range<usize>,
2354        bounds: RectF,
2355        _: RectF,
2356        layout: &Self::LayoutState,
2357        _: &Self::PaintState,
2358        _: &Editor,
2359        _: &ViewContext<Editor>,
2360    ) -> Option<RectF> {
2361        let text_bounds = RectF::new(
2362            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2363            layout.text_size,
2364        );
2365        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2366        let scroll_position = layout.position_map.snapshot.scroll_position();
2367        let start_row = scroll_position.y() as u32;
2368        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2369        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2370
2371        let range_start = OffsetUtf16(range_utf16.start)
2372            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2373        if range_start.row() < start_row {
2374            return None;
2375        }
2376
2377        let line = &layout
2378            .position_map
2379            .line_layouts
2380            .get((range_start.row() - start_row) as usize)?
2381            .line;
2382        let range_start_x = line.x_for_index(range_start.column() as usize);
2383        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2384        Some(RectF::new(
2385            content_origin
2386                + vec2f(
2387                    range_start_x,
2388                    range_start_y + layout.position_map.line_height,
2389                )
2390                - vec2f(scroll_left, scroll_top),
2391            vec2f(
2392                layout.position_map.em_width,
2393                layout.position_map.line_height,
2394            ),
2395        ))
2396    }
2397
2398    fn debug(
2399        &self,
2400        bounds: RectF,
2401        _: &Self::LayoutState,
2402        _: &Self::PaintState,
2403        _: &Editor,
2404        _: &ViewContext<Editor>,
2405    ) -> json::Value {
2406        json!({
2407            "type": "BufferElement",
2408            "bounds": bounds.to_json()
2409        })
2410    }
2411}
2412
2413type BufferRow = u32;
2414
2415pub struct LayoutState {
2416    position_map: Arc<PositionMap>,
2417    gutter_size: Vector2F,
2418    gutter_padding: f32,
2419    gutter_margin: f32,
2420    text_size: Vector2F,
2421    mode: EditorMode,
2422    visible_display_row_range: Range<u32>,
2423    active_rows: BTreeMap<u32, bool>,
2424    highlighted_rows: Option<Range<u32>>,
2425    line_number_layouts: Vec<Option<text_layout::Line>>,
2426    display_hunks: Vec<DisplayDiffHunk>,
2427    blocks: Vec<BlockLayout>,
2428    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2429    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2430    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2431    scrollbar_row_range: Range<f32>,
2432    show_scrollbars: bool,
2433    max_row: u32,
2434    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2435    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2436    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2437    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2438    tab_invisible: Line,
2439    space_invisible: Line,
2440}
2441
2442struct PositionMap {
2443    size: Vector2F,
2444    line_height: f32,
2445    scroll_max: Vector2F,
2446    em_width: f32,
2447    em_advance: f32,
2448    line_layouts: Vec<LineWithInvisibles>,
2449    snapshot: EditorSnapshot,
2450}
2451
2452impl PositionMap {
2453    /// Returns two display points:
2454    /// 1. The nearest *valid* position in the editor
2455    /// 2. An unclipped, potentially *invalid* position that maps directly to
2456    ///    the given pixel position.
2457    fn point_for_position(
2458        &self,
2459        text_bounds: RectF,
2460        position: Vector2F,
2461    ) -> (DisplayPoint, DisplayPoint) {
2462        let scroll_position = self.snapshot.scroll_position();
2463        let position = position - text_bounds.origin();
2464        let y = position.y().max(0.0).min(self.size.y());
2465        let x = position.x() + (scroll_position.x() * self.em_width);
2466        let row = (y / self.line_height + scroll_position.y()) as u32;
2467        let (column, x_overshoot) = if let Some(line) = self
2468            .line_layouts
2469            .get(row as usize - scroll_position.y() as usize)
2470            .map(|line_with_spaces| &line_with_spaces.line)
2471        {
2472            if let Some(ix) = line.index_for_x(x) {
2473                (ix as u32, 0.0)
2474            } else {
2475                (line.len() as u32, 0f32.max(x - line.width()))
2476            }
2477        } else {
2478            (0, x)
2479        };
2480
2481        let mut target_point = DisplayPoint::new(row, column);
2482        let point = self.snapshot.clip_point(target_point, Bias::Left);
2483        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2484
2485        (point, target_point)
2486    }
2487}
2488
2489struct BlockLayout {
2490    row: u32,
2491    element: AnyElement<Editor>,
2492    style: BlockStyle,
2493}
2494
2495fn layout_line(
2496    row: u32,
2497    snapshot: &EditorSnapshot,
2498    style: &EditorStyle,
2499    layout_cache: &TextLayoutCache,
2500) -> text_layout::Line {
2501    let mut line = snapshot.line(row);
2502
2503    if line.len() > MAX_LINE_LEN {
2504        let mut len = MAX_LINE_LEN;
2505        while !line.is_char_boundary(len) {
2506            len -= 1;
2507        }
2508
2509        line.truncate(len);
2510    }
2511
2512    layout_cache.layout_str(
2513        &line,
2514        style.text.font_size,
2515        &[(
2516            snapshot.line_len(row) as usize,
2517            RunStyle {
2518                font_id: style.text.font_id,
2519                color: Color::black(),
2520                underline: Default::default(),
2521            },
2522        )],
2523    )
2524}
2525
2526#[derive(Debug)]
2527pub struct Cursor {
2528    origin: Vector2F,
2529    block_width: f32,
2530    line_height: f32,
2531    color: Color,
2532    shape: CursorShape,
2533    block_text: Option<Line>,
2534}
2535
2536impl Cursor {
2537    pub fn new(
2538        origin: Vector2F,
2539        block_width: f32,
2540        line_height: f32,
2541        color: Color,
2542        shape: CursorShape,
2543        block_text: Option<Line>,
2544    ) -> Cursor {
2545        Cursor {
2546            origin,
2547            block_width,
2548            line_height,
2549            color,
2550            shape,
2551            block_text,
2552        }
2553    }
2554
2555    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2556        RectF::new(
2557            self.origin + origin,
2558            vec2f(self.block_width, self.line_height),
2559        )
2560    }
2561
2562    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2563        let bounds = match self.shape {
2564            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2565            CursorShape::Block | CursorShape::Hollow => RectF::new(
2566                self.origin + origin,
2567                vec2f(self.block_width, self.line_height),
2568            ),
2569            CursorShape::Underscore => RectF::new(
2570                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2571                vec2f(self.block_width, 2.0),
2572            ),
2573        };
2574
2575        //Draw background or border quad
2576        if matches!(self.shape, CursorShape::Hollow) {
2577            scene.push_quad(Quad {
2578                bounds,
2579                background: None,
2580                border: Border::all(1., self.color),
2581                corner_radius: 0.,
2582            });
2583        } else {
2584            scene.push_quad(Quad {
2585                bounds,
2586                background: Some(self.color),
2587                border: Default::default(),
2588                corner_radius: 0.,
2589            });
2590        }
2591
2592        if let Some(block_text) = &self.block_text {
2593            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2594        }
2595    }
2596
2597    pub fn shape(&self) -> CursorShape {
2598        self.shape
2599    }
2600}
2601
2602#[derive(Debug)]
2603pub struct HighlightedRange {
2604    pub start_y: f32,
2605    pub line_height: f32,
2606    pub lines: Vec<HighlightedRangeLine>,
2607    pub color: Color,
2608    pub corner_radius: f32,
2609}
2610
2611#[derive(Debug)]
2612pub struct HighlightedRangeLine {
2613    pub start_x: f32,
2614    pub end_x: f32,
2615}
2616
2617impl HighlightedRange {
2618    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2619        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2620            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2621            self.paint_lines(
2622                self.start_y + self.line_height,
2623                &self.lines[1..],
2624                bounds,
2625                scene,
2626            );
2627        } else {
2628            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2629        }
2630    }
2631
2632    fn paint_lines(
2633        &self,
2634        start_y: f32,
2635        lines: &[HighlightedRangeLine],
2636        bounds: RectF,
2637        scene: &mut SceneBuilder,
2638    ) {
2639        if lines.is_empty() {
2640            return;
2641        }
2642
2643        let mut path = PathBuilder::new();
2644        let first_line = lines.first().unwrap();
2645        let last_line = lines.last().unwrap();
2646
2647        let first_top_left = vec2f(first_line.start_x, start_y);
2648        let first_top_right = vec2f(first_line.end_x, start_y);
2649
2650        let curve_height = vec2f(0., self.corner_radius);
2651        let curve_width = |start_x: f32, end_x: f32| {
2652            let max = (end_x - start_x) / 2.;
2653            let width = if max < self.corner_radius {
2654                max
2655            } else {
2656                self.corner_radius
2657            };
2658
2659            vec2f(width, 0.)
2660        };
2661
2662        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2663        path.reset(first_top_right - top_curve_width);
2664        path.curve_to(first_top_right + curve_height, first_top_right);
2665
2666        let mut iter = lines.iter().enumerate().peekable();
2667        while let Some((ix, line)) = iter.next() {
2668            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2669
2670            if let Some((_, next_line)) = iter.peek() {
2671                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2672
2673                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2674                    Ordering::Equal => {
2675                        path.line_to(bottom_right);
2676                    }
2677                    Ordering::Less => {
2678                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2679                        path.line_to(bottom_right - curve_height);
2680                        if self.corner_radius > 0. {
2681                            path.curve_to(bottom_right - curve_width, bottom_right);
2682                        }
2683                        path.line_to(next_top_right + curve_width);
2684                        if self.corner_radius > 0. {
2685                            path.curve_to(next_top_right + curve_height, next_top_right);
2686                        }
2687                    }
2688                    Ordering::Greater => {
2689                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2690                        path.line_to(bottom_right - curve_height);
2691                        if self.corner_radius > 0. {
2692                            path.curve_to(bottom_right + curve_width, bottom_right);
2693                        }
2694                        path.line_to(next_top_right - curve_width);
2695                        if self.corner_radius > 0. {
2696                            path.curve_to(next_top_right + curve_height, next_top_right);
2697                        }
2698                    }
2699                }
2700            } else {
2701                let curve_width = curve_width(line.start_x, line.end_x);
2702                path.line_to(bottom_right - curve_height);
2703                if self.corner_radius > 0. {
2704                    path.curve_to(bottom_right - curve_width, bottom_right);
2705                }
2706
2707                let bottom_left = vec2f(line.start_x, bottom_right.y());
2708                path.line_to(bottom_left + curve_width);
2709                if self.corner_radius > 0. {
2710                    path.curve_to(bottom_left - curve_height, bottom_left);
2711                }
2712            }
2713        }
2714
2715        if first_line.start_x > last_line.start_x {
2716            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2717            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2718            path.line_to(second_top_left + curve_height);
2719            if self.corner_radius > 0. {
2720                path.curve_to(second_top_left + curve_width, second_top_left);
2721            }
2722            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2723            path.line_to(first_bottom_left - curve_width);
2724            if self.corner_radius > 0. {
2725                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2726            }
2727        }
2728
2729        path.line_to(first_top_left + curve_height);
2730        if self.corner_radius > 0. {
2731            path.curve_to(first_top_left + top_curve_width, first_top_left);
2732        }
2733        path.line_to(first_top_right - top_curve_width);
2734
2735        scene.push_path(path.build(self.color, Some(bounds)));
2736    }
2737}
2738
2739fn position_to_display_point(
2740    position: Vector2F,
2741    text_bounds: RectF,
2742    position_map: &PositionMap,
2743) -> Option<DisplayPoint> {
2744    if text_bounds.contains_point(position) {
2745        let (point, target_point) = position_map.point_for_position(text_bounds, position);
2746        if point == target_point {
2747            Some(point)
2748        } else {
2749            None
2750        }
2751    } else {
2752        None
2753    }
2754}
2755
2756fn range_to_bounds(
2757    range: &Range<DisplayPoint>,
2758    content_origin: Vector2F,
2759    scroll_left: f32,
2760    scroll_top: f32,
2761    visible_row_range: &Range<u32>,
2762    line_end_overshoot: f32,
2763    position_map: &PositionMap,
2764) -> impl Iterator<Item = RectF> {
2765    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2766
2767    if range.start == range.end {
2768        return bounds.into_iter();
2769    }
2770
2771    let start_row = visible_row_range.start;
2772    let end_row = visible_row_range.end;
2773
2774    let row_range = if range.end.column() == 0 {
2775        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2776    } else {
2777        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2778    };
2779
2780    let first_y =
2781        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
2782
2783    for (idx, row) in row_range.enumerate() {
2784        let line_layout = &position_map.line_layouts[(row - start_row) as usize].line;
2785
2786        let start_x = if row == range.start.row() {
2787            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
2788                - scroll_left
2789        } else {
2790            content_origin.x() - scroll_left
2791        };
2792
2793        let end_x = if row == range.end.row() {
2794            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
2795        } else {
2796            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
2797        };
2798
2799        bounds.push(RectF::from_points(
2800            vec2f(start_x, first_y + position_map.line_height * idx as f32),
2801            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
2802        ))
2803    }
2804
2805    bounds.into_iter()
2806}
2807
2808pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2809    delta.powf(1.5) / 100.0
2810}
2811
2812fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2813    delta.powf(1.2) / 300.0
2814}
2815
2816#[cfg(test)]
2817mod tests {
2818    use super::*;
2819    use crate::{
2820        display_map::{BlockDisposition, BlockProperties},
2821        Editor, MultiBuffer,
2822    };
2823    use gpui::TestAppContext;
2824    use log::info;
2825    use settings::Settings;
2826    use std::{num::NonZeroU32, sync::Arc};
2827    use util::test::sample_text;
2828
2829    #[gpui::test]
2830    fn test_layout_line_numbers(cx: &mut TestAppContext) {
2831        cx.update(|cx| cx.set_global(Settings::test(cx)));
2832        let (_, editor) = cx.add_window(|cx| {
2833            let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2834            Editor::new(EditorMode::Full, buffer, None, None, cx)
2835        });
2836        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2837
2838        let layouts = editor.update(cx, |editor, cx| {
2839            let snapshot = editor.snapshot(cx);
2840            element
2841                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
2842                .0
2843        });
2844        assert_eq!(layouts.len(), 6);
2845    }
2846
2847    #[gpui::test]
2848    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
2849        cx.update(|cx| cx.set_global(Settings::test(cx)));
2850        let (_, editor) = cx.add_window(|cx| {
2851            let buffer = MultiBuffer::build_simple("", cx);
2852            Editor::new(EditorMode::Full, buffer, None, None, cx)
2853        });
2854
2855        editor.update(cx, |editor, cx| {
2856            editor.set_placeholder_text("hello", cx);
2857            editor.insert_blocks(
2858                [BlockProperties {
2859                    style: BlockStyle::Fixed,
2860                    disposition: BlockDisposition::Above,
2861                    height: 3,
2862                    position: Anchor::min(),
2863                    render: Arc::new(|_| Empty::new().into_any()),
2864                }],
2865                cx,
2866            );
2867
2868            // Blur the editor so that it displays placeholder text.
2869            cx.blur();
2870        });
2871
2872        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2873        let (size, mut state) = editor.update(cx, |editor, cx| {
2874            let mut new_parents = Default::default();
2875            let mut notify_views_if_parents_change = Default::default();
2876            let mut layout_cx = LayoutContext::new(
2877                cx,
2878                &mut new_parents,
2879                &mut notify_views_if_parents_change,
2880                false,
2881            );
2882            element.layout(
2883                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2884                editor,
2885                &mut layout_cx,
2886            )
2887        });
2888
2889        assert_eq!(state.position_map.line_layouts.len(), 4);
2890        assert_eq!(
2891            state
2892                .line_number_layouts
2893                .iter()
2894                .map(Option::is_some)
2895                .collect::<Vec<_>>(),
2896            &[false, false, false, true]
2897        );
2898
2899        // Don't panic.
2900        let mut scene = SceneBuilder::new(1.0);
2901        let bounds = RectF::new(Default::default(), size);
2902        editor.update(cx, |editor, cx| {
2903            element.paint(&mut scene, bounds, bounds, &mut state, editor, cx);
2904        });
2905    }
2906
2907    #[gpui::test]
2908    fn test_all_invisibles_drawing(cx: &mut TestAppContext) {
2909        let tab_size = 4;
2910        let input_text = "\t \t|\t| a b";
2911        let expected_invisibles = vec![
2912            Invisible::Tab {
2913                line_start_offset: 0,
2914            },
2915            Invisible::Whitespace {
2916                line_offset: tab_size as usize,
2917            },
2918            Invisible::Tab {
2919                line_start_offset: tab_size as usize + 1,
2920            },
2921            Invisible::Tab {
2922                line_start_offset: tab_size as usize * 2 + 1,
2923            },
2924            Invisible::Whitespace {
2925                line_offset: tab_size as usize * 3 + 1,
2926            },
2927            Invisible::Whitespace {
2928                line_offset: tab_size as usize * 3 + 3,
2929            },
2930        ];
2931        assert_eq!(
2932            expected_invisibles.len(),
2933            input_text
2934                .chars()
2935                .filter(|initial_char| initial_char.is_whitespace())
2936                .count(),
2937            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
2938        );
2939
2940        cx.update(|cx| {
2941            let mut test_settings = Settings::test(cx);
2942            test_settings.editor_defaults.show_whitespaces = Some(ShowWhitespaces::All);
2943            test_settings.editor_defaults.tab_size = Some(NonZeroU32::new(tab_size).unwrap());
2944            cx.set_global(test_settings);
2945        });
2946        let actual_invisibles =
2947            collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, 500.0);
2948
2949        assert_eq!(expected_invisibles, actual_invisibles);
2950    }
2951
2952    #[gpui::test]
2953    fn test_invisibles_dont_appear_in_certain_editors(cx: &mut TestAppContext) {
2954        cx.update(|cx| {
2955            let mut test_settings = Settings::test(cx);
2956            test_settings.editor_defaults.show_whitespaces = Some(ShowWhitespaces::All);
2957            test_settings.editor_defaults.tab_size = Some(NonZeroU32::new(4).unwrap());
2958            cx.set_global(test_settings);
2959        });
2960
2961        for editor_mode_without_invisibles in [
2962            EditorMode::SingleLine,
2963            EditorMode::AutoHeight { max_lines: 100 },
2964        ] {
2965            let invisibles = collect_invisibles_from_new_editor(
2966                cx,
2967                editor_mode_without_invisibles,
2968                "\t\t\t| | a b",
2969                500.0,
2970            );
2971            assert!(invisibles.is_empty(),
2972                "For editor mode {editor_mode_without_invisibles:?} no invisibles was expected but got {invisibles:?}");
2973        }
2974    }
2975
2976    #[gpui::test]
2977    fn test_wrapped_invisibles_drawing(cx: &mut TestAppContext) {
2978        let tab_size = 4;
2979        let input_text = "a\tbcd   ".repeat(9);
2980        let repeated_invisibles = [
2981            Invisible::Tab {
2982                line_start_offset: 1,
2983            },
2984            Invisible::Whitespace {
2985                line_offset: tab_size as usize + 3,
2986            },
2987            Invisible::Whitespace {
2988                line_offset: tab_size as usize + 4,
2989            },
2990            Invisible::Whitespace {
2991                line_offset: tab_size as usize + 5,
2992            },
2993        ];
2994        let expected_invisibles = std::iter::once(repeated_invisibles)
2995            .cycle()
2996            .take(9)
2997            .flatten()
2998            .collect::<Vec<_>>();
2999        assert_eq!(
3000            expected_invisibles.len(),
3001            input_text
3002                .chars()
3003                .filter(|initial_char| initial_char.is_whitespace())
3004                .count(),
3005            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3006        );
3007        info!("Expected invisibles: {expected_invisibles:?}");
3008
3009        // Put the same string with repeating whitespace pattern into editors of various size,
3010        // take deliberately small steps during resizing, to put all whitespace kinds near the wrap point.
3011        let resize_step = 10.0;
3012        let mut editor_width = 200.0;
3013        while editor_width <= 1000.0 {
3014            cx.update(|cx| {
3015                let mut test_settings = Settings::test(cx);
3016                test_settings.editor_defaults.tab_size = Some(NonZeroU32::new(tab_size).unwrap());
3017                test_settings.editor_defaults.show_whitespaces = Some(ShowWhitespaces::All);
3018                test_settings.editor_defaults.preferred_line_length = Some(editor_width as u32);
3019                test_settings.editor_defaults.soft_wrap =
3020                    Some(settings::SoftWrap::PreferredLineLength);
3021                cx.set_global(test_settings);
3022            });
3023
3024            let actual_invisibles =
3025                collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, editor_width);
3026
3027            // Whatever the editor size is, ensure it has the same invisible kinds in the same order
3028            // (no good guarantees about the offsets: wrapping could trigger padding and its tests should check the offsets).
3029            let mut i = 0;
3030            for (actual_index, actual_invisible) in actual_invisibles.iter().enumerate() {
3031                i = actual_index;
3032                match expected_invisibles.get(i) {
3033                    Some(expected_invisible) => match (expected_invisible, actual_invisible) {
3034                        (Invisible::Whitespace { .. }, Invisible::Whitespace { .. })
3035                        | (Invisible::Tab { .. }, Invisible::Tab { .. }) => {}
3036                        _ => {
3037                            panic!("At index {i}, expected invisible {expected_invisible:?} does not match actual {actual_invisible:?} by kind. Actual invisibles: {actual_invisibles:?}")
3038                        }
3039                    },
3040                    None => panic!("Unexpected extra invisible {actual_invisible:?} at index {i}"),
3041                }
3042            }
3043            let missing_expected_invisibles = &expected_invisibles[i + 1..];
3044            assert!(
3045                missing_expected_invisibles.is_empty(),
3046                "Missing expected invisibles after index {i}: {missing_expected_invisibles:?}"
3047            );
3048
3049            editor_width += resize_step;
3050        }
3051    }
3052
3053    fn collect_invisibles_from_new_editor(
3054        cx: &mut TestAppContext,
3055        editor_mode: EditorMode,
3056        input_text: &str,
3057        editor_width: f32,
3058    ) -> Vec<Invisible> {
3059        info!(
3060            "Creating editor with mode {editor_mode:?}, witdh {editor_width} and text '{input_text}'"
3061        );
3062        let (_, editor) = cx.add_window(|cx| {
3063            let buffer = MultiBuffer::build_simple(&input_text, cx);
3064            Editor::new(editor_mode, buffer, None, None, cx)
3065        });
3066
3067        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3068        let (_, layout_state) = editor.update(cx, |editor, cx| {
3069            editor.set_soft_wrap_mode(settings::SoftWrap::EditorWidth, cx);
3070            editor.set_wrap_width(Some(editor_width), cx);
3071
3072            let mut new_parents = Default::default();
3073            let mut notify_views_if_parents_change = Default::default();
3074            let mut layout_cx = LayoutContext::new(
3075                cx,
3076                &mut new_parents,
3077                &mut notify_views_if_parents_change,
3078                false,
3079            );
3080            element.layout(
3081                SizeConstraint::new(vec2f(editor_width, 500.), vec2f(editor_width, 500.)),
3082                editor,
3083                &mut layout_cx,
3084            )
3085        });
3086
3087        layout_state
3088            .position_map
3089            .line_layouts
3090            .iter()
3091            .map(|line_with_invisibles| &line_with_invisibles.invisibles)
3092            .flatten()
3093            .cloned()
3094            .collect()
3095    }
3096}