element.rs

   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, InlayOffset, TransformBlock},
   8    editor_settings::ShowScrollbar,
   9    git::{diff_hunk_to_display, DisplayDiffHunk},
  10    hover_popover::{
  11        hide_hover, hover_at, HOVER_POPOVER_GAP, MIN_POPOVER_CHARACTER_WIDTH,
  12        MIN_POPOVER_LINE_HEIGHT,
  13    },
  14    link_go_to_definition::{
  15        go_to_fetched_definition, go_to_fetched_type_definition, update_go_to_definition_link,
  16        GoToDefinitionTrigger,
  17    },
  18    mouse_context_menu, EditorSettings, EditorStyle, GutterHover, UnfoldAt,
  19};
  20use clock::ReplicaId;
  21use collections::{BTreeMap, HashMap};
  22use git::diff::DiffHunkStatus;
  23use gpui::{
  24    color::Color,
  25    elements::*,
  26    fonts::{HighlightStyle, TextStyle, Underline},
  27    geometry::{
  28        rect::RectF,
  29        vector::{vec2f, Vector2F},
  30        PathBuilder,
  31    },
  32    json::{self, ToJson},
  33    platform::{CursorStyle, Modifiers, MouseButton, MouseButtonEvent, MouseMovedEvent},
  34    text_layout::{self, Line, RunStyle, TextLayoutCache},
  35    AnyElement, Axis, Border, CursorRegion, Element, EventContext, FontCache, LayoutContext,
  36    MouseRegion, PaintContext, Quad, SceneBuilder, SizeConstraint, ViewContext, WindowContext,
  37};
  38use itertools::Itertools;
  39use json::json;
  40use language::{
  41    language_settings::ShowWhitespaceSetting, Bias, CursorShape, DiagnosticSeverity, OffsetUtf16,
  42    Selection,
  43};
  44use project::{
  45    project_settings::{GitGutterSetting, ProjectSettings},
  46    InlayHintLabelPart, Location, LocationLink, ProjectPath, ResolveState,
  47};
  48use smallvec::SmallVec;
  49use std::{
  50    borrow::Cow,
  51    cmp::{self, Ordering},
  52    fmt::Write,
  53    iter,
  54    ops::Range,
  55    sync::Arc,
  56};
  57use text::Point;
  58use workspace::item::Item;
  59
  60enum FoldMarkers {}
  61
  62struct SelectionLayout {
  63    head: DisplayPoint,
  64    cursor_shape: CursorShape,
  65    is_newest: bool,
  66    is_local: bool,
  67    range: Range<DisplayPoint>,
  68    active_rows: Range<u32>,
  69}
  70
  71impl SelectionLayout {
  72    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  73        selection: Selection<T>,
  74        line_mode: bool,
  75        cursor_shape: CursorShape,
  76        map: &DisplaySnapshot,
  77        is_newest: bool,
  78        is_local: bool,
  79    ) -> Self {
  80        let point_selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  81        let display_selection = point_selection.map(|p| p.to_display_point(map));
  82        let mut range = display_selection.range();
  83        let mut head = display_selection.head();
  84        let mut active_rows = map.prev_line_boundary(point_selection.start).1.row()
  85            ..map.next_line_boundary(point_selection.end).1.row();
  86
  87        // vim visual line mode
  88        if line_mode {
  89            let point_range = map.expand_to_line(point_selection.range());
  90            range = point_range.start.to_display_point(map)..point_range.end.to_display_point(map);
  91        }
  92
  93        // any vim visual mode (including line mode)
  94        if cursor_shape == CursorShape::Block && !range.is_empty() && !selection.reversed {
  95            if head.column() > 0 {
  96                head = map.clip_point(DisplayPoint::new(head.row(), head.column() - 1), Bias::Left)
  97            } else if head.row() > 0 && head != map.max_point() {
  98                head = map.clip_point(
  99                    DisplayPoint::new(head.row() - 1, map.line_len(head.row() - 1)),
 100                    Bias::Left,
 101                );
 102                // updating range.end is a no-op unless you're cursor is
 103                // on the newline containing a multi-buffer divider
 104                // in which case the clip_point may have moved the head up
 105                // an additional row.
 106                range.end = DisplayPoint::new(head.row() + 1, 0);
 107                active_rows.end = head.row();
 108            }
 109        }
 110
 111        Self {
 112            head,
 113            cursor_shape,
 114            is_newest,
 115            is_local,
 116            range,
 117            active_rows,
 118        }
 119    }
 120}
 121
 122pub struct EditorElement {
 123    style: Arc<EditorStyle>,
 124}
 125
 126impl EditorElement {
 127    pub fn new(style: EditorStyle) -> Self {
 128        Self {
 129            style: Arc::new(style),
 130        }
 131    }
 132
 133    fn attach_mouse_handlers(
 134        scene: &mut SceneBuilder,
 135        position_map: &Arc<PositionMap>,
 136        has_popovers: bool,
 137        visible_bounds: RectF,
 138        text_bounds: RectF,
 139        gutter_bounds: RectF,
 140        bounds: RectF,
 141        cx: &mut ViewContext<Editor>,
 142    ) {
 143        enum EditorElementMouseHandlers {}
 144        scene.push_mouse_region(
 145            MouseRegion::new::<EditorElementMouseHandlers>(
 146                cx.view_id(),
 147                cx.view_id(),
 148                visible_bounds,
 149            )
 150            .on_down(MouseButton::Left, {
 151                let position_map = position_map.clone();
 152                move |event, editor, cx| {
 153                    if !Self::mouse_down(
 154                        editor,
 155                        event.platform_event,
 156                        position_map.as_ref(),
 157                        text_bounds,
 158                        gutter_bounds,
 159                        cx,
 160                    ) {
 161                        cx.propagate_event();
 162                    }
 163                }
 164            })
 165            .on_down(MouseButton::Right, {
 166                let position_map = position_map.clone();
 167                move |event, editor, cx| {
 168                    if !Self::mouse_right_down(
 169                        editor,
 170                        event.position,
 171                        position_map.as_ref(),
 172                        text_bounds,
 173                        cx,
 174                    ) {
 175                        cx.propagate_event();
 176                    }
 177                }
 178            })
 179            .on_up(MouseButton::Left, {
 180                let position_map = position_map.clone();
 181                move |event, editor, cx| {
 182                    if !Self::mouse_up(
 183                        editor,
 184                        event.position,
 185                        event.cmd,
 186                        event.shift,
 187                        event.alt,
 188                        position_map.as_ref(),
 189                        text_bounds,
 190                        cx,
 191                    ) {
 192                        cx.propagate_event()
 193                    }
 194                }
 195            })
 196            .on_drag(MouseButton::Left, {
 197                let position_map = position_map.clone();
 198                move |event, editor, cx| {
 199                    if event.end {
 200                        return;
 201                    }
 202
 203                    if !Self::mouse_dragged(
 204                        editor,
 205                        event.platform_event,
 206                        position_map.as_ref(),
 207                        text_bounds,
 208                        cx,
 209                    ) {
 210                        cx.propagate_event()
 211                    }
 212                }
 213            })
 214            .on_move({
 215                let position_map = position_map.clone();
 216                move |event, editor, cx| {
 217                    if !Self::mouse_moved(
 218                        editor,
 219                        event.platform_event,
 220                        &position_map,
 221                        text_bounds,
 222                        cx,
 223                    ) {
 224                        cx.propagate_event()
 225                    }
 226                }
 227            })
 228            .on_move_out(move |_, editor: &mut Editor, cx| {
 229                if has_popovers {
 230                    hide_hover(editor, cx);
 231                }
 232            })
 233            .on_scroll({
 234                let position_map = position_map.clone();
 235                move |event, editor, cx| {
 236                    if !Self::scroll(
 237                        editor,
 238                        event.position,
 239                        *event.delta.raw(),
 240                        event.delta.precise(),
 241                        &position_map,
 242                        bounds,
 243                        cx,
 244                    ) {
 245                        cx.propagate_event()
 246                    }
 247                }
 248            }),
 249        );
 250
 251        enum GutterHandlers {}
 252        scene.push_mouse_region(
 253            MouseRegion::new::<GutterHandlers>(cx.view_id(), cx.view_id() + 1, gutter_bounds)
 254                .on_hover(|hover, editor: &mut Editor, cx| {
 255                    editor.gutter_hover(
 256                        &GutterHover {
 257                            hovered: hover.started,
 258                        },
 259                        cx,
 260                    );
 261                }),
 262        )
 263    }
 264
 265    fn mouse_down(
 266        editor: &mut Editor,
 267        MouseButtonEvent {
 268            position,
 269            modifiers:
 270                Modifiers {
 271                    shift,
 272                    ctrl,
 273                    alt,
 274                    cmd,
 275                    ..
 276                },
 277            mut click_count,
 278            ..
 279        }: MouseButtonEvent,
 280        position_map: &PositionMap,
 281        text_bounds: RectF,
 282        gutter_bounds: RectF,
 283        cx: &mut EventContext<Editor>,
 284    ) -> bool {
 285        if gutter_bounds.contains_point(position) {
 286            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 287        } else if !text_bounds.contains_point(position) {
 288            return false;
 289        }
 290
 291        let point_for_position = position_map.point_for_position(text_bounds, position);
 292        let position = point_for_position.previous_valid;
 293        if shift && alt {
 294            editor.select(
 295                SelectPhase::BeginColumnar {
 296                    position,
 297                    goal_column: point_for_position.exact_unclipped.column(),
 298                },
 299                cx,
 300            );
 301        } else if shift && !ctrl && !alt && !cmd {
 302            editor.select(
 303                SelectPhase::Extend {
 304                    position,
 305                    click_count,
 306                },
 307                cx,
 308            );
 309        } else {
 310            editor.select(
 311                SelectPhase::Begin {
 312                    position,
 313                    add: alt,
 314                    click_count,
 315                },
 316                cx,
 317            );
 318        }
 319
 320        true
 321    }
 322
 323    fn mouse_right_down(
 324        editor: &mut Editor,
 325        position: Vector2F,
 326        position_map: &PositionMap,
 327        text_bounds: RectF,
 328        cx: &mut EventContext<Editor>,
 329    ) -> bool {
 330        if !text_bounds.contains_point(position) {
 331            return false;
 332        }
 333        let point_for_position = position_map.point_for_position(text_bounds, position);
 334        mouse_context_menu::deploy_context_menu(
 335            editor,
 336            position,
 337            point_for_position.previous_valid,
 338            cx,
 339        );
 340        true
 341    }
 342
 343    fn mouse_up(
 344        editor: &mut Editor,
 345        position: Vector2F,
 346        cmd: bool,
 347        shift: bool,
 348        alt: bool,
 349        position_map: &PositionMap,
 350        text_bounds: RectF,
 351        cx: &mut EventContext<Editor>,
 352    ) -> bool {
 353        let end_selection = editor.has_pending_selection();
 354        let pending_nonempty_selections = editor.has_pending_nonempty_selection();
 355
 356        if end_selection {
 357            editor.select(SelectPhase::End, cx);
 358        }
 359
 360        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 361            if let Some(point) = position_map
 362                .point_for_position(text_bounds, position)
 363                .as_valid()
 364            {
 365                if shift {
 366                    go_to_fetched_type_definition(editor, point, alt, cx);
 367                } else {
 368                    go_to_fetched_definition(editor, point, alt, cx);
 369                }
 370
 371                return true;
 372            }
 373        }
 374
 375        end_selection
 376    }
 377
 378    fn mouse_dragged(
 379        editor: &mut Editor,
 380        MouseMovedEvent {
 381            modifiers: Modifiers { cmd, shift, .. },
 382            position,
 383            ..
 384        }: MouseMovedEvent,
 385        position_map: &PositionMap,
 386        text_bounds: RectF,
 387        cx: &mut EventContext<Editor>,
 388    ) -> bool {
 389        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 390        // Don't trigger hover popover if mouse is hovering over context menu
 391        let point = if text_bounds.contains_point(position) {
 392            position_map
 393                .point_for_position(text_bounds, position)
 394                .as_valid()
 395        } else {
 396            None
 397        };
 398
 399        update_go_to_definition_link(
 400            editor,
 401            point
 402                .map(GoToDefinitionTrigger::Text)
 403                .unwrap_or(GoToDefinitionTrigger::None),
 404            cmd,
 405            shift,
 406            cx,
 407        );
 408
 409        if editor.has_pending_selection() {
 410            let mut scroll_delta = Vector2F::zero();
 411
 412            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 413            let top = text_bounds.origin_y() + vertical_margin;
 414            let bottom = text_bounds.lower_left().y() - vertical_margin;
 415            if position.y() < top {
 416                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 417            }
 418            if position.y() > bottom {
 419                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 420            }
 421
 422            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 423            let left = text_bounds.origin_x() + horizontal_margin;
 424            let right = text_bounds.upper_right().x() - horizontal_margin;
 425            if position.x() < left {
 426                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 427                    left - position.x(),
 428                ))
 429            }
 430            if position.x() > right {
 431                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 432                    position.x() - right,
 433                ))
 434            }
 435
 436            let point_for_position = position_map.point_for_position(text_bounds, position);
 437
 438            editor.select(
 439                SelectPhase::Update {
 440                    position: point_for_position.previous_valid,
 441                    goal_column: point_for_position.exact_unclipped.column(),
 442                    scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 443                        .clamp(Vector2F::zero(), position_map.scroll_max),
 444                },
 445                cx,
 446            );
 447            hover_at(editor, point, cx);
 448            true
 449        } else {
 450            hover_at(editor, point, cx);
 451            false
 452        }
 453    }
 454
 455    fn mouse_moved(
 456        editor: &mut Editor,
 457        MouseMovedEvent {
 458            modifiers: Modifiers { shift, cmd, .. },
 459            position,
 460            ..
 461        }: MouseMovedEvent,
 462        position_map: &PositionMap,
 463        text_bounds: RectF,
 464        cx: &mut ViewContext<Editor>,
 465    ) -> bool {
 466        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 467        // Don't trigger hover popover if mouse is hovering over context menu
 468        if text_bounds.contains_point(position) {
 469            let point_for_position = position_map.point_for_position(text_bounds, position);
 470            match point_for_position.as_valid() {
 471                Some(point) => {
 472                    update_go_to_definition_link(
 473                        editor,
 474                        GoToDefinitionTrigger::Text(point),
 475                        cmd,
 476                        shift,
 477                        cx,
 478                    );
 479                    hover_at(editor, Some(point), cx);
 480                }
 481                None => {
 482                    update_inlay_link_and_hover_points(
 483                        position_map,
 484                        point_for_position,
 485                        editor,
 486                        (cmd, shift),
 487                        cx,
 488                    );
 489                }
 490            }
 491        } else {
 492            update_go_to_definition_link(editor, GoToDefinitionTrigger::None, cmd, shift, cx);
 493            hover_at(editor, None, cx);
 494        }
 495
 496        true
 497    }
 498
 499    fn scroll(
 500        editor: &mut Editor,
 501        position: Vector2F,
 502        mut delta: Vector2F,
 503        precise: bool,
 504        position_map: &PositionMap,
 505        bounds: RectF,
 506        cx: &mut ViewContext<Editor>,
 507    ) -> bool {
 508        if !bounds.contains_point(position) {
 509            return false;
 510        }
 511
 512        let line_height = position_map.line_height;
 513        let max_glyph_width = position_map.em_width;
 514
 515        let axis = if precise {
 516            //Trackpad
 517            position_map.snapshot.ongoing_scroll.filter(&mut delta)
 518        } else {
 519            //Not trackpad
 520            delta *= vec2f(max_glyph_width, line_height);
 521            None //Resets ongoing scroll
 522        };
 523
 524        let scroll_position = position_map.snapshot.scroll_position();
 525        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 526        let y = (scroll_position.y() * line_height - delta.y()) / line_height;
 527        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 528        editor.scroll(scroll_position, axis, cx);
 529
 530        true
 531    }
 532
 533    fn paint_background(
 534        &self,
 535        scene: &mut SceneBuilder,
 536        gutter_bounds: RectF,
 537        text_bounds: RectF,
 538        layout: &LayoutState,
 539    ) {
 540        let bounds = gutter_bounds.union_rect(text_bounds);
 541        let scroll_top =
 542            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 543        scene.push_quad(Quad {
 544            bounds: gutter_bounds,
 545            background: Some(self.style.gutter_background),
 546            border: Border::new(0., Color::transparent_black()),
 547            corner_radii: Default::default(),
 548        });
 549        scene.push_quad(Quad {
 550            bounds: text_bounds,
 551            background: Some(self.style.background),
 552            border: Border::new(0., Color::transparent_black()),
 553            corner_radii: Default::default(),
 554        });
 555
 556        if let EditorMode::Full = layout.mode {
 557            let mut active_rows = layout.active_rows.iter().peekable();
 558            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 559                let mut end_row = *start_row;
 560                while active_rows.peek().map_or(false, |r| {
 561                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 562                }) {
 563                    active_rows.next().unwrap();
 564                    end_row += 1;
 565                }
 566
 567                if !contains_non_empty_selection {
 568                    let origin = vec2f(
 569                        bounds.origin_x(),
 570                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 571                            - scroll_top,
 572                    );
 573                    let size = vec2f(
 574                        bounds.width(),
 575                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 576                    );
 577                    scene.push_quad(Quad {
 578                        bounds: RectF::new(origin, size),
 579                        background: Some(self.style.active_line_background),
 580                        border: Border::default(),
 581                        corner_radii: Default::default(),
 582                    });
 583                }
 584            }
 585
 586            if let Some(highlighted_rows) = &layout.highlighted_rows {
 587                let origin = vec2f(
 588                    bounds.origin_x(),
 589                    bounds.origin_y()
 590                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 591                        - scroll_top,
 592                );
 593                let size = vec2f(
 594                    bounds.width(),
 595                    layout.position_map.line_height * highlighted_rows.len() as f32,
 596                );
 597                scene.push_quad(Quad {
 598                    bounds: RectF::new(origin, size),
 599                    background: Some(self.style.highlighted_line_background),
 600                    border: Border::default(),
 601                    corner_radii: Default::default(),
 602                });
 603            }
 604
 605            let scroll_left =
 606                layout.position_map.snapshot.scroll_position().x() * layout.position_map.em_width;
 607
 608            for (wrap_position, active) in layout.wrap_guides.iter() {
 609                let x =
 610                    (text_bounds.origin_x() + wrap_position + layout.position_map.em_width / 2.)
 611                        - scroll_left;
 612
 613                if x < text_bounds.origin_x()
 614                    || (layout.show_scrollbars && x > self.scrollbar_left(&bounds))
 615                {
 616                    continue;
 617                }
 618
 619                let color = if *active {
 620                    self.style.active_wrap_guide
 621                } else {
 622                    self.style.wrap_guide
 623                };
 624                scene.push_quad(Quad {
 625                    bounds: RectF::new(
 626                        vec2f(x, text_bounds.origin_y()),
 627                        vec2f(1., text_bounds.height()),
 628                    ),
 629                    background: Some(color),
 630                    border: Border::new(0., Color::transparent_black()),
 631                    corner_radii: Default::default(),
 632                });
 633            }
 634        }
 635    }
 636
 637    fn paint_gutter(
 638        &mut self,
 639        scene: &mut SceneBuilder,
 640        bounds: RectF,
 641        visible_bounds: RectF,
 642        layout: &mut LayoutState,
 643        editor: &mut Editor,
 644        cx: &mut PaintContext<Editor>,
 645    ) {
 646        let line_height = layout.position_map.line_height;
 647
 648        let scroll_position = layout.position_map.snapshot.scroll_position();
 649        let scroll_top = scroll_position.y() * line_height;
 650
 651        let show_gutter = matches!(
 652            settings::get::<ProjectSettings>(cx).git.git_gutter,
 653            Some(GitGutterSetting::TrackedFiles)
 654        );
 655
 656        if show_gutter {
 657            Self::paint_diff_hunks(scene, bounds, layout, cx);
 658        }
 659
 660        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 661            if let Some(line) = line {
 662                let line_origin = bounds.origin()
 663                    + vec2f(
 664                        bounds.width() - line.width() - layout.gutter_padding,
 665                        ix as f32 * line_height - (scroll_top % line_height),
 666                    );
 667
 668                line.paint(scene, line_origin, visible_bounds, line_height, cx);
 669            }
 670        }
 671
 672        for (ix, fold_indicator) in layout.fold_indicators.iter_mut().enumerate() {
 673            if let Some(indicator) = fold_indicator.as_mut() {
 674                let position = vec2f(
 675                    bounds.width() - layout.gutter_padding,
 676                    ix as f32 * line_height - (scroll_top % line_height),
 677                );
 678                let centering_offset = vec2f(
 679                    (layout.gutter_padding + layout.gutter_margin - indicator.size().x()) / 2.,
 680                    (line_height - indicator.size().y()) / 2.,
 681                );
 682
 683                let indicator_origin = bounds.origin() + position + centering_offset;
 684
 685                indicator.paint(scene, indicator_origin, visible_bounds, editor, cx);
 686            }
 687        }
 688
 689        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 690            let mut x = 0.;
 691            let mut y = *row as f32 * line_height - scroll_top;
 692            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 693            y += (line_height - indicator.size().y()) / 2.;
 694            indicator.paint(
 695                scene,
 696                bounds.origin() + vec2f(x, y),
 697                visible_bounds,
 698                editor,
 699                cx,
 700            );
 701        }
 702    }
 703
 704    fn paint_diff_hunks(
 705        scene: &mut SceneBuilder,
 706        bounds: RectF,
 707        layout: &mut LayoutState,
 708        cx: &mut ViewContext<Editor>,
 709    ) {
 710        let diff_style = &theme::current(cx).editor.diff.clone();
 711        let line_height = layout.position_map.line_height;
 712
 713        let scroll_position = layout.position_map.snapshot.scroll_position();
 714        let scroll_top = scroll_position.y() * line_height;
 715
 716        for hunk in &layout.display_hunks {
 717            let (display_row_range, status) = match hunk {
 718                //TODO: This rendering is entirely a horrible hack
 719                &DisplayDiffHunk::Folded { display_row: row } => {
 720                    let start_y = row as f32 * line_height - scroll_top;
 721                    let end_y = start_y + line_height;
 722
 723                    let width = diff_style.removed_width_em * line_height;
 724                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 725                    let highlight_size = vec2f(width * 2., end_y - start_y);
 726                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 727
 728                    scene.push_quad(Quad {
 729                        bounds: highlight_bounds,
 730                        background: Some(diff_style.modified),
 731                        border: Border::new(0., Color::transparent_black()),
 732                        corner_radii: (1. * line_height).into(),
 733                    });
 734
 735                    continue;
 736                }
 737
 738                DisplayDiffHunk::Unfolded {
 739                    display_row_range,
 740                    status,
 741                } => (display_row_range, status),
 742            };
 743
 744            let color = match status {
 745                DiffHunkStatus::Added => diff_style.inserted,
 746                DiffHunkStatus::Modified => diff_style.modified,
 747
 748                //TODO: This rendering is entirely a horrible hack
 749                DiffHunkStatus::Removed => {
 750                    let row = display_row_range.start;
 751
 752                    let offset = line_height / 2.;
 753                    let start_y = row as f32 * line_height - offset - scroll_top;
 754                    let end_y = start_y + line_height;
 755
 756                    let width = diff_style.removed_width_em * line_height;
 757                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 758                    let highlight_size = vec2f(width * 2., end_y - start_y);
 759                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 760
 761                    scene.push_quad(Quad {
 762                        bounds: highlight_bounds,
 763                        background: Some(diff_style.deleted),
 764                        border: Border::new(0., Color::transparent_black()),
 765                        corner_radii: (1. * line_height).into(),
 766                    });
 767
 768                    continue;
 769                }
 770            };
 771
 772            let start_row = display_row_range.start;
 773            let end_row = display_row_range.end;
 774
 775            let start_y = start_row as f32 * line_height - scroll_top;
 776            let end_y = end_row as f32 * line_height - scroll_top;
 777
 778            let width = diff_style.width_em * line_height;
 779            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 780            let highlight_size = vec2f(width * 2., end_y - start_y);
 781            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 782
 783            scene.push_quad(Quad {
 784                bounds: highlight_bounds,
 785                background: Some(color),
 786                border: Border::new(0., Color::transparent_black()),
 787                corner_radii: (diff_style.corner_radius * line_height).into(),
 788            });
 789        }
 790    }
 791
 792    fn paint_text(
 793        &mut self,
 794        scene: &mut SceneBuilder,
 795        bounds: RectF,
 796        visible_bounds: RectF,
 797        layout: &mut LayoutState,
 798        editor: &mut Editor,
 799        cx: &mut PaintContext<Editor>,
 800    ) {
 801        let style = &self.style;
 802        let scroll_position = layout.position_map.snapshot.scroll_position();
 803        let start_row = layout.visible_display_row_range.start;
 804        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 805        let max_glyph_width = layout.position_map.em_width;
 806        let scroll_left = scroll_position.x() * max_glyph_width;
 807        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 808        let line_end_overshoot = 0.15 * layout.position_map.line_height;
 809        let whitespace_setting = editor.buffer.read(cx).settings_at(0, cx).show_whitespaces;
 810
 811        scene.push_layer(Some(bounds));
 812
 813        scene.push_cursor_region(CursorRegion {
 814            bounds,
 815            style: if !editor.link_go_to_definition_state.definitions.is_empty() {
 816                CursorStyle::PointingHand
 817            } else {
 818                CursorStyle::IBeam
 819            },
 820        });
 821
 822        let fold_corner_radius =
 823            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
 824        for (id, range, color) in layout.fold_ranges.iter() {
 825            self.paint_highlighted_range(
 826                scene,
 827                range.clone(),
 828                *color,
 829                fold_corner_radius,
 830                fold_corner_radius * 2.,
 831                layout,
 832                content_origin,
 833                scroll_top,
 834                scroll_left,
 835                bounds,
 836            );
 837
 838            for bound in range_to_bounds(
 839                &range,
 840                content_origin,
 841                scroll_left,
 842                scroll_top,
 843                &layout.visible_display_row_range,
 844                line_end_overshoot,
 845                &layout.position_map,
 846            ) {
 847                scene.push_cursor_region(CursorRegion {
 848                    bounds: bound,
 849                    style: CursorStyle::PointingHand,
 850                });
 851
 852                let display_row = range.start.row();
 853
 854                let buffer_row = DisplayPoint::new(display_row, 0)
 855                    .to_point(&layout.position_map.snapshot.display_snapshot)
 856                    .row;
 857
 858                scene.push_mouse_region(
 859                    MouseRegion::new::<FoldMarkers>(cx.view_id(), *id as usize, bound)
 860                        .on_click(MouseButton::Left, move |_, editor: &mut Editor, cx| {
 861                            editor.unfold_at(&UnfoldAt { buffer_row }, cx)
 862                        })
 863                        .with_notify_on_hover(true)
 864                        .with_notify_on_click(true),
 865                )
 866            }
 867        }
 868
 869        for (range, color) in &layout.highlighted_ranges {
 870            self.paint_highlighted_range(
 871                scene,
 872                range.clone(),
 873                *color,
 874                0.,
 875                line_end_overshoot,
 876                layout,
 877                content_origin,
 878                scroll_top,
 879                scroll_left,
 880                bounds,
 881            );
 882        }
 883
 884        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 885        let corner_radius = 0.15 * layout.position_map.line_height;
 886        let mut invisible_display_ranges = SmallVec::<[Range<DisplayPoint>; 32]>::new();
 887
 888        for (replica_id, selections) in &layout.selections {
 889            let replica_id = *replica_id;
 890            let selection_style = if let Some(replica_id) = replica_id {
 891                style.replica_selection_style(replica_id)
 892            } else {
 893                &style.absent_selection
 894            };
 895
 896            for selection in selections {
 897                self.paint_highlighted_range(
 898                    scene,
 899                    selection.range.clone(),
 900                    selection_style.selection,
 901                    corner_radius,
 902                    corner_radius * 2.,
 903                    layout,
 904                    content_origin,
 905                    scroll_top,
 906                    scroll_left,
 907                    bounds,
 908                );
 909
 910                if selection.is_local && !selection.range.is_empty() {
 911                    invisible_display_ranges.push(selection.range.clone());
 912                }
 913                if !selection.is_local || editor.show_local_cursors(cx) {
 914                    let cursor_position = selection.head;
 915                    if layout
 916                        .visible_display_row_range
 917                        .contains(&cursor_position.row())
 918                    {
 919                        let cursor_row_layout = &layout.position_map.line_layouts
 920                            [(cursor_position.row() - start_row) as usize]
 921                            .line;
 922                        let cursor_column = cursor_position.column() as usize;
 923
 924                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 925                        let mut block_width =
 926                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 927                        if block_width == 0.0 {
 928                            block_width = layout.position_map.em_width;
 929                        }
 930                        let block_text = if let CursorShape::Block = selection.cursor_shape {
 931                            layout
 932                                .position_map
 933                                .snapshot
 934                                .chars_at(cursor_position)
 935                                .next()
 936                                .and_then(|(character, _)| {
 937                                    let font_id =
 938                                        cursor_row_layout.font_for_index(cursor_column)?;
 939                                    let text = character.to_string();
 940
 941                                    Some(cx.text_layout_cache().layout_str(
 942                                        &text,
 943                                        cursor_row_layout.font_size(),
 944                                        &[(
 945                                            text.chars().count(),
 946                                            RunStyle {
 947                                                font_id,
 948                                                color: style.background,
 949                                                underline: Default::default(),
 950                                            },
 951                                        )],
 952                                    ))
 953                                })
 954                        } else {
 955                            None
 956                        };
 957
 958                        let x = cursor_character_x - scroll_left;
 959                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 960                            - scroll_top;
 961                        if selection.is_newest {
 962                            editor.pixel_position_of_newest_cursor = Some(vec2f(
 963                                bounds.origin_x() + x + block_width / 2.,
 964                                bounds.origin_y() + y + layout.position_map.line_height / 2.,
 965                            ));
 966                        }
 967                        cursors.push(Cursor {
 968                            color: selection_style.cursor,
 969                            block_width,
 970                            origin: vec2f(x, y),
 971                            line_height: layout.position_map.line_height,
 972                            shape: selection.cursor_shape,
 973                            block_text,
 974                        });
 975                    }
 976                }
 977            }
 978        }
 979
 980        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 981            for (ix, line_with_invisibles) in layout.position_map.line_layouts.iter().enumerate() {
 982                let row = start_row + ix as u32;
 983                line_with_invisibles.draw(
 984                    layout,
 985                    row,
 986                    scroll_top,
 987                    scene,
 988                    content_origin,
 989                    scroll_left,
 990                    visible_text_bounds,
 991                    whitespace_setting,
 992                    &invisible_display_ranges,
 993                    visible_bounds,
 994                    cx,
 995                )
 996            }
 997        }
 998
 999        scene.paint_layer(Some(bounds), |scene| {
1000            for cursor in cursors {
1001                cursor.paint(scene, content_origin, cx);
1002            }
1003        });
1004
1005        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
1006            scene.push_stacking_context(None, None);
1007            let cursor_row_layout =
1008                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
1009            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
1010            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
1011            let mut list_origin = content_origin + vec2f(x, y);
1012            let list_width = context_menu.size().x();
1013            let list_height = context_menu.size().y();
1014
1015            // Snap the right edge of the list to the right edge of the window if
1016            // its horizontal bounds overflow.
1017            if list_origin.x() + list_width > cx.window_size().x() {
1018                list_origin.set_x((cx.window_size().x() - list_width).max(0.));
1019            }
1020
1021            if list_origin.y() + list_height > bounds.max_y() {
1022                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
1023            }
1024
1025            context_menu.paint(
1026                scene,
1027                list_origin,
1028                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1029                editor,
1030                cx,
1031            );
1032
1033            scene.pop_stacking_context();
1034        }
1035
1036        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
1037            scene.push_stacking_context(None, None);
1038
1039            // This is safe because we check on layout whether the required row is available
1040            let hovered_row_layout =
1041                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
1042
1043            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
1044            // height. This is the size we will use to decide whether to render popovers above or below
1045            // the hovered line.
1046            let first_size = hover_popovers[0].size();
1047            let height_to_reserve = first_size.y()
1048                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
1049
1050            // Compute Hovered Point
1051            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
1052            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
1053            let hovered_point = content_origin + vec2f(x, y);
1054
1055            if hovered_point.y() - height_to_reserve > 0.0 {
1056                // There is enough space above. Render popovers above the hovered point
1057                let mut current_y = hovered_point.y();
1058                for hover_popover in hover_popovers {
1059                    let size = hover_popover.size();
1060                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
1061
1062                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
1063                    if x_out_of_bounds < 0.0 {
1064                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
1065                    }
1066
1067                    hover_popover.paint(
1068                        scene,
1069                        popover_origin,
1070                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1071                        editor,
1072                        cx,
1073                    );
1074
1075                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
1076                }
1077            } else {
1078                // There is not enough space above. Render popovers below the hovered point
1079                let mut current_y = hovered_point.y() + layout.position_map.line_height;
1080                for hover_popover in hover_popovers {
1081                    let size = hover_popover.size();
1082                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
1083
1084                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
1085                    if x_out_of_bounds < 0.0 {
1086                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
1087                    }
1088
1089                    hover_popover.paint(
1090                        scene,
1091                        popover_origin,
1092                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1093                        editor,
1094                        cx,
1095                    );
1096
1097                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
1098                }
1099            }
1100
1101            scene.pop_stacking_context();
1102        }
1103
1104        scene.pop_layer();
1105    }
1106
1107    fn scrollbar_left(&self, bounds: &RectF) -> f32 {
1108        bounds.max_x() - self.style.theme.scrollbar.width
1109    }
1110
1111    fn paint_scrollbar(
1112        &mut self,
1113        scene: &mut SceneBuilder,
1114        bounds: RectF,
1115        layout: &mut LayoutState,
1116        cx: &mut ViewContext<Editor>,
1117        editor: &Editor,
1118    ) {
1119        enum ScrollbarMouseHandlers {}
1120        if layout.mode != EditorMode::Full {
1121            return;
1122        }
1123
1124        let style = &self.style.theme.scrollbar;
1125
1126        let top = bounds.min_y();
1127        let bottom = bounds.max_y();
1128        let right = bounds.max_x();
1129        let left = self.scrollbar_left(&bounds);
1130        let row_range = &layout.scrollbar_row_range;
1131        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
1132
1133        let mut height = bounds.height();
1134        let mut first_row_y_offset = 0.0;
1135
1136        // Impose a minimum height on the scrollbar thumb
1137        let row_height = height / max_row;
1138        let min_thumb_height =
1139            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
1140        let thumb_height = (row_range.end - row_range.start) * row_height;
1141        if thumb_height < min_thumb_height {
1142            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
1143            height -= min_thumb_height - thumb_height;
1144        }
1145
1146        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * row_height };
1147
1148        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
1149        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
1150        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
1151        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
1152
1153        if layout.show_scrollbars {
1154            scene.push_quad(Quad {
1155                bounds: track_bounds,
1156                border: style.track.border,
1157                background: style.track.background_color,
1158                ..Default::default()
1159            });
1160            let scrollbar_settings = settings::get::<EditorSettings>(cx).scrollbar;
1161            let theme = theme::current(cx);
1162            let scrollbar_theme = &theme.editor.scrollbar;
1163            if layout.is_singleton && scrollbar_settings.selections {
1164                let start_anchor = Anchor::min();
1165                let end_anchor = Anchor::max();
1166                let color = scrollbar_theme.selections;
1167                let border = Border {
1168                    width: 1.,
1169                    color: style.thumb.border.color,
1170                    overlay: false,
1171                    top: false,
1172                    right: true,
1173                    bottom: false,
1174                    left: true,
1175                };
1176                let mut push_region = |start: DisplayPoint, end: DisplayPoint| {
1177                    let start_y = y_for_row(start.row() as f32);
1178                    let mut end_y = y_for_row(end.row() as f32);
1179                    if end_y - start_y < 1. {
1180                        end_y = start_y + 1.;
1181                    }
1182                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1183
1184                    scene.push_quad(Quad {
1185                        bounds,
1186                        background: Some(color),
1187                        border,
1188                        corner_radii: style.thumb.corner_radii.into(),
1189                    })
1190                };
1191                let background_ranges = editor
1192                    .background_highlight_row_ranges::<crate::items::BufferSearchHighlights>(
1193                        start_anchor..end_anchor,
1194                        &layout.position_map.snapshot,
1195                        50000,
1196                    );
1197                for row in background_ranges {
1198                    let start = row.start();
1199                    let end = row.end();
1200                    push_region(*start, *end);
1201                }
1202            }
1203
1204            if layout.is_singleton && scrollbar_settings.git_diff {
1205                let diff_style = scrollbar_theme.git.clone();
1206                for hunk in layout
1207                    .position_map
1208                    .snapshot
1209                    .buffer_snapshot
1210                    .git_diff_hunks_in_range(0..(max_row.floor() as u32))
1211                {
1212                    let start_display = Point::new(hunk.buffer_range.start, 0)
1213                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1214                    let end_display = Point::new(hunk.buffer_range.end, 0)
1215                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1216                    let start_y = y_for_row(start_display.row() as f32);
1217                    let mut end_y = if hunk.buffer_range.start == hunk.buffer_range.end {
1218                        y_for_row((end_display.row() + 1) as f32)
1219                    } else {
1220                        y_for_row((end_display.row()) as f32)
1221                    };
1222
1223                    if end_y - start_y < 1. {
1224                        end_y = start_y + 1.;
1225                    }
1226                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1227
1228                    let color = match hunk.status() {
1229                        DiffHunkStatus::Added => diff_style.inserted,
1230                        DiffHunkStatus::Modified => diff_style.modified,
1231                        DiffHunkStatus::Removed => diff_style.deleted,
1232                    };
1233
1234                    let border = Border {
1235                        width: 1.,
1236                        color: style.thumb.border.color,
1237                        overlay: false,
1238                        top: false,
1239                        right: true,
1240                        bottom: false,
1241                        left: true,
1242                    };
1243
1244                    scene.push_quad(Quad {
1245                        bounds,
1246                        background: Some(color),
1247                        border,
1248                        corner_radii: style.thumb.corner_radii.into(),
1249                    })
1250                }
1251            }
1252
1253            scene.push_quad(Quad {
1254                bounds: thumb_bounds,
1255                border: style.thumb.border,
1256                background: style.thumb.background_color,
1257                corner_radii: style.thumb.corner_radii.into(),
1258            });
1259        }
1260
1261        scene.push_cursor_region(CursorRegion {
1262            bounds: track_bounds,
1263            style: CursorStyle::Arrow,
1264        });
1265        scene.push_mouse_region(
1266            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1267                .on_move(move |event, editor: &mut Editor, cx| {
1268                    if event.pressed_button.is_none() {
1269                        editor.scroll_manager.show_scrollbar(cx);
1270                    }
1271                })
1272                .on_down(MouseButton::Left, {
1273                    let row_range = row_range.clone();
1274                    move |event, editor: &mut Editor, cx| {
1275                        let y = event.position.y();
1276                        if y < thumb_top || thumb_bottom < y {
1277                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1278                            let top_row = center_row
1279                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1280                            let mut position = editor.scroll_position(cx);
1281                            position.set_y(top_row as f32);
1282                            editor.set_scroll_position(position, cx);
1283                        } else {
1284                            editor.scroll_manager.show_scrollbar(cx);
1285                        }
1286                    }
1287                })
1288                .on_drag(MouseButton::Left, {
1289                    move |event, editor: &mut Editor, cx| {
1290                        if event.end {
1291                            return;
1292                        }
1293
1294                        let y = event.prev_mouse_position.y();
1295                        let new_y = event.position.y();
1296                        if thumb_top < y && y < thumb_bottom {
1297                            let mut position = editor.scroll_position(cx);
1298                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1299                            if position.y() < 0.0 {
1300                                position.set_y(0.);
1301                            }
1302                            editor.set_scroll_position(position, cx);
1303                        }
1304                    }
1305                }),
1306        );
1307    }
1308
1309    #[allow(clippy::too_many_arguments)]
1310    fn paint_highlighted_range(
1311        &self,
1312        scene: &mut SceneBuilder,
1313        range: Range<DisplayPoint>,
1314        color: Color,
1315        corner_radius: f32,
1316        line_end_overshoot: f32,
1317        layout: &LayoutState,
1318        content_origin: Vector2F,
1319        scroll_top: f32,
1320        scroll_left: f32,
1321        bounds: RectF,
1322    ) {
1323        let start_row = layout.visible_display_row_range.start;
1324        let end_row = layout.visible_display_row_range.end;
1325        if range.start != range.end {
1326            let row_range = if range.end.column() == 0 {
1327                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1328            } else {
1329                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1330            };
1331
1332            let highlighted_range = HighlightedRange {
1333                color,
1334                line_height: layout.position_map.line_height,
1335                corner_radius,
1336                start_y: content_origin.y()
1337                    + row_range.start as f32 * layout.position_map.line_height
1338                    - scroll_top,
1339                lines: row_range
1340                    .into_iter()
1341                    .map(|row| {
1342                        let line_layout =
1343                            &layout.position_map.line_layouts[(row - start_row) as usize].line;
1344                        HighlightedRangeLine {
1345                            start_x: if row == range.start.row() {
1346                                content_origin.x()
1347                                    + line_layout.x_for_index(range.start.column() as usize)
1348                                    - scroll_left
1349                            } else {
1350                                content_origin.x() - scroll_left
1351                            },
1352                            end_x: if row == range.end.row() {
1353                                content_origin.x()
1354                                    + line_layout.x_for_index(range.end.column() as usize)
1355                                    - scroll_left
1356                            } else {
1357                                content_origin.x() + line_layout.width() + line_end_overshoot
1358                                    - scroll_left
1359                            },
1360                        }
1361                    })
1362                    .collect(),
1363            };
1364
1365            highlighted_range.paint(bounds, scene);
1366        }
1367    }
1368
1369    fn paint_blocks(
1370        &mut self,
1371        scene: &mut SceneBuilder,
1372        bounds: RectF,
1373        visible_bounds: RectF,
1374        layout: &mut LayoutState,
1375        editor: &mut Editor,
1376        cx: &mut PaintContext<Editor>,
1377    ) {
1378        let scroll_position = layout.position_map.snapshot.scroll_position();
1379        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1380        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1381
1382        for block in &mut layout.blocks {
1383            let mut origin = bounds.origin()
1384                + vec2f(
1385                    0.,
1386                    block.row as f32 * layout.position_map.line_height - scroll_top,
1387                );
1388            if !matches!(block.style, BlockStyle::Sticky) {
1389                origin += vec2f(-scroll_left, 0.);
1390            }
1391            block
1392                .element
1393                .paint(scene, origin, visible_bounds, editor, cx);
1394        }
1395    }
1396
1397    fn column_pixels(&self, column: usize, cx: &ViewContext<Editor>) -> f32 {
1398        let style = &self.style;
1399
1400        cx.text_layout_cache()
1401            .layout_str(
1402                " ".repeat(column).as_str(),
1403                style.text.font_size,
1404                &[(
1405                    column,
1406                    RunStyle {
1407                        font_id: style.text.font_id,
1408                        color: Color::black(),
1409                        underline: Default::default(),
1410                    },
1411                )],
1412            )
1413            .width()
1414    }
1415
1416    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1417        let digit_count = (snapshot.max_buffer_row() as f32 + 1.).log10().floor() as usize + 1;
1418        self.column_pixels(digit_count, cx)
1419    }
1420
1421    //Folds contained in a hunk are ignored apart from shrinking visual size
1422    //If a fold contains any hunks then that fold line is marked as modified
1423    fn layout_git_gutters(
1424        &self,
1425        display_rows: Range<u32>,
1426        snapshot: &EditorSnapshot,
1427    ) -> Vec<DisplayDiffHunk> {
1428        let buffer_snapshot = &snapshot.buffer_snapshot;
1429
1430        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1431            .to_point(snapshot)
1432            .row;
1433        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1434            .to_point(snapshot)
1435            .row;
1436
1437        buffer_snapshot
1438            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row)
1439            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1440            .dedup()
1441            .collect()
1442    }
1443
1444    fn layout_line_numbers(
1445        &self,
1446        rows: Range<u32>,
1447        active_rows: &BTreeMap<u32, bool>,
1448        is_singleton: bool,
1449        snapshot: &EditorSnapshot,
1450        cx: &ViewContext<Editor>,
1451    ) -> (
1452        Vec<Option<text_layout::Line>>,
1453        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1454    ) {
1455        let style = &self.style;
1456        let include_line_numbers = snapshot.mode == EditorMode::Full;
1457        let mut line_number_layouts = Vec::with_capacity(rows.len());
1458        let mut fold_statuses = Vec::with_capacity(rows.len());
1459        let mut line_number = String::new();
1460        for (ix, row) in snapshot
1461            .buffer_rows(rows.start)
1462            .take((rows.end - rows.start) as usize)
1463            .enumerate()
1464        {
1465            let display_row = rows.start + ix as u32;
1466            let (active, color) = if active_rows.contains_key(&display_row) {
1467                (true, style.line_number_active)
1468            } else {
1469                (false, style.line_number)
1470            };
1471            if let Some(buffer_row) = row {
1472                if include_line_numbers {
1473                    line_number.clear();
1474                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1475                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1476                        &line_number,
1477                        style.text.font_size,
1478                        &[(
1479                            line_number.len(),
1480                            RunStyle {
1481                                font_id: style.text.font_id,
1482                                color,
1483                                underline: Default::default(),
1484                            },
1485                        )],
1486                    )));
1487                    fold_statuses.push(
1488                        is_singleton
1489                            .then(|| {
1490                                snapshot
1491                                    .fold_for_line(buffer_row)
1492                                    .map(|fold_status| (fold_status, buffer_row, active))
1493                            })
1494                            .flatten(),
1495                    )
1496                }
1497            } else {
1498                fold_statuses.push(None);
1499                line_number_layouts.push(None);
1500            }
1501        }
1502
1503        (line_number_layouts, fold_statuses)
1504    }
1505
1506    fn layout_lines(
1507        &mut self,
1508        rows: Range<u32>,
1509        line_number_layouts: &[Option<Line>],
1510        snapshot: &EditorSnapshot,
1511        cx: &ViewContext<Editor>,
1512    ) -> Vec<LineWithInvisibles> {
1513        if rows.start >= rows.end {
1514            return Vec::new();
1515        }
1516
1517        // When the editor is empty and unfocused, then show the placeholder.
1518        if snapshot.is_empty() {
1519            let placeholder_style = self
1520                .style
1521                .placeholder_text
1522                .as_ref()
1523                .unwrap_or(&self.style.text);
1524            let placeholder_text = snapshot.placeholder_text();
1525            let placeholder_lines = placeholder_text
1526                .as_ref()
1527                .map_or("", AsRef::as_ref)
1528                .split('\n')
1529                .skip(rows.start as usize)
1530                .chain(iter::repeat(""))
1531                .take(rows.len());
1532            placeholder_lines
1533                .map(|line| {
1534                    cx.text_layout_cache().layout_str(
1535                        line,
1536                        placeholder_style.font_size,
1537                        &[(
1538                            line.len(),
1539                            RunStyle {
1540                                font_id: placeholder_style.font_id,
1541                                color: placeholder_style.color,
1542                                underline: Default::default(),
1543                            },
1544                        )],
1545                    )
1546                })
1547                .map(|line| LineWithInvisibles {
1548                    line,
1549                    invisibles: Vec::new(),
1550                })
1551                .collect()
1552        } else {
1553            let style = &self.style;
1554            let chunks = snapshot
1555                .chunks(
1556                    rows.clone(),
1557                    true,
1558                    Some(style.theme.hint),
1559                    Some(style.theme.suggestion),
1560                )
1561                .map(|chunk| {
1562                    let mut highlight_style = chunk
1563                        .syntax_highlight_id
1564                        .and_then(|id| id.style(&style.syntax));
1565
1566                    if let Some(chunk_highlight) = chunk.highlight_style {
1567                        if let Some(highlight_style) = highlight_style.as_mut() {
1568                            highlight_style.highlight(chunk_highlight);
1569                        } else {
1570                            highlight_style = Some(chunk_highlight);
1571                        }
1572                    }
1573
1574                    let mut diagnostic_highlight = HighlightStyle::default();
1575
1576                    if chunk.is_unnecessary {
1577                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1578                    }
1579
1580                    if let Some(severity) = chunk.diagnostic_severity {
1581                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1582                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1583                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1584                            diagnostic_highlight.underline = Some(Underline {
1585                                color: Some(diagnostic_style.message.text.color),
1586                                thickness: 1.0.into(),
1587                                squiggly: true,
1588                            });
1589                        }
1590                    }
1591
1592                    if let Some(highlight_style) = highlight_style.as_mut() {
1593                        highlight_style.highlight(diagnostic_highlight);
1594                    } else {
1595                        highlight_style = Some(diagnostic_highlight);
1596                    }
1597
1598                    HighlightedChunk {
1599                        chunk: chunk.text,
1600                        style: highlight_style,
1601                        is_tab: chunk.is_tab,
1602                    }
1603                });
1604
1605            LineWithInvisibles::from_chunks(
1606                chunks,
1607                &style.text,
1608                cx.text_layout_cache(),
1609                cx.font_cache(),
1610                MAX_LINE_LEN,
1611                rows.len() as usize,
1612                line_number_layouts,
1613                snapshot.mode,
1614            )
1615        }
1616    }
1617
1618    #[allow(clippy::too_many_arguments)]
1619    fn layout_blocks(
1620        &mut self,
1621        rows: Range<u32>,
1622        snapshot: &EditorSnapshot,
1623        editor_width: f32,
1624        scroll_width: f32,
1625        gutter_padding: f32,
1626        gutter_width: f32,
1627        em_width: f32,
1628        text_x: f32,
1629        line_height: f32,
1630        style: &EditorStyle,
1631        line_layouts: &[LineWithInvisibles],
1632        editor: &mut Editor,
1633        cx: &mut LayoutContext<Editor>,
1634    ) -> (f32, Vec<BlockLayout>) {
1635        let mut block_id = 0;
1636        let scroll_x = snapshot.scroll_anchor.offset.x();
1637        let (fixed_blocks, non_fixed_blocks) = snapshot
1638            .blocks_in_range(rows.clone())
1639            .partition::<Vec<_>, _>(|(_, block)| match block {
1640                TransformBlock::ExcerptHeader { .. } => false,
1641                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1642            });
1643        let mut render_block = |block: &TransformBlock, width: f32, block_id: usize| {
1644            let mut element = match block {
1645                TransformBlock::Custom(block) => {
1646                    let align_to = block
1647                        .position()
1648                        .to_point(&snapshot.buffer_snapshot)
1649                        .to_display_point(snapshot);
1650                    let anchor_x = text_x
1651                        + if rows.contains(&align_to.row()) {
1652                            line_layouts[(align_to.row() - rows.start) as usize]
1653                                .line
1654                                .x_for_index(align_to.column() as usize)
1655                        } else {
1656                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1657                                .x_for_index(align_to.column() as usize)
1658                        };
1659
1660                    block.render(&mut BlockContext {
1661                        view_context: cx,
1662                        anchor_x,
1663                        gutter_padding,
1664                        line_height,
1665                        scroll_x,
1666                        gutter_width,
1667                        em_width,
1668                        block_id,
1669                    })
1670                }
1671                TransformBlock::ExcerptHeader {
1672                    id,
1673                    buffer,
1674                    range,
1675                    starts_new_buffer,
1676                    ..
1677                } => {
1678                    let tooltip_style = theme::current(cx).tooltip.clone();
1679                    let include_root = editor
1680                        .project
1681                        .as_ref()
1682                        .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1683                        .unwrap_or_default();
1684                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1685                        let jump_path = ProjectPath {
1686                            worktree_id: file.worktree_id(cx),
1687                            path: file.path.clone(),
1688                        };
1689                        let jump_anchor = range
1690                            .primary
1691                            .as_ref()
1692                            .map_or(range.context.start, |primary| primary.start);
1693                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1694
1695                        enum JumpIcon {}
1696                        MouseEventHandler::new::<JumpIcon, _>((*id).into(), cx, |state, _| {
1697                            let style = style.jump_icon.style_for(state);
1698                            Svg::new("icons/arrow_up_right_8.svg")
1699                                .with_color(style.color)
1700                                .constrained()
1701                                .with_width(style.icon_width)
1702                                .aligned()
1703                                .contained()
1704                                .with_style(style.container)
1705                                .constrained()
1706                                .with_width(style.button_width)
1707                                .with_height(style.button_width)
1708                        })
1709                        .with_cursor_style(CursorStyle::PointingHand)
1710                        .on_click(MouseButton::Left, move |_, editor, cx| {
1711                            if let Some(workspace) = editor
1712                                .workspace
1713                                .as_ref()
1714                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1715                            {
1716                                workspace.update(cx, |workspace, cx| {
1717                                    Editor::jump(
1718                                        workspace,
1719                                        jump_path.clone(),
1720                                        jump_position,
1721                                        jump_anchor,
1722                                        cx,
1723                                    );
1724                                });
1725                            }
1726                        })
1727                        .with_tooltip::<JumpIcon>(
1728                            (*id).into(),
1729                            "Jump to Buffer".to_string(),
1730                            Some(Box::new(crate::OpenExcerpts)),
1731                            tooltip_style.clone(),
1732                            cx,
1733                        )
1734                        .aligned()
1735                        .flex_float()
1736                    });
1737
1738                    if *starts_new_buffer {
1739                        let editor_font_size = style.text.font_size;
1740                        let style = &style.diagnostic_path_header;
1741                        let font_size = (style.text_scale_factor * editor_font_size).round();
1742
1743                        let path = buffer.resolve_file_path(cx, include_root);
1744                        let mut filename = None;
1745                        let mut parent_path = None;
1746                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1747                        if let Some(path) = path {
1748                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1749                            parent_path =
1750                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1751                        }
1752
1753                        Flex::row()
1754                            .with_child(
1755                                Label::new(
1756                                    filename.unwrap_or_else(|| "untitled".to_string()),
1757                                    style.filename.text.clone().with_font_size(font_size),
1758                                )
1759                                .contained()
1760                                .with_style(style.filename.container)
1761                                .aligned(),
1762                            )
1763                            .with_children(parent_path.map(|path| {
1764                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1765                                    .contained()
1766                                    .with_style(style.path.container)
1767                                    .aligned()
1768                            }))
1769                            .with_children(jump_icon)
1770                            .contained()
1771                            .with_style(style.container)
1772                            .with_padding_left(gutter_padding)
1773                            .with_padding_right(gutter_padding)
1774                            .expanded()
1775                            .into_any_named("path header block")
1776                    } else {
1777                        let text_style = style.text.clone();
1778                        Flex::row()
1779                            .with_child(Label::new("", text_style))
1780                            .with_children(jump_icon)
1781                            .contained()
1782                            .with_padding_left(gutter_padding)
1783                            .with_padding_right(gutter_padding)
1784                            .expanded()
1785                            .into_any_named("collapsed context")
1786                    }
1787                }
1788            };
1789
1790            element.layout(
1791                SizeConstraint {
1792                    min: Vector2F::zero(),
1793                    max: vec2f(width, block.height() as f32 * line_height),
1794                },
1795                editor,
1796                cx,
1797            );
1798            element
1799        };
1800
1801        let mut fixed_block_max_width = 0f32;
1802        let mut blocks = Vec::new();
1803        for (row, block) in fixed_blocks {
1804            let element = render_block(block, f32::INFINITY, block_id);
1805            block_id += 1;
1806            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1807            blocks.push(BlockLayout {
1808                row,
1809                element,
1810                style: BlockStyle::Fixed,
1811            });
1812        }
1813        for (row, block) in non_fixed_blocks {
1814            let style = match block {
1815                TransformBlock::Custom(block) => block.style(),
1816                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1817            };
1818            let width = match style {
1819                BlockStyle::Sticky => editor_width,
1820                BlockStyle::Flex => editor_width
1821                    .max(fixed_block_max_width)
1822                    .max(gutter_width + scroll_width),
1823                BlockStyle::Fixed => unreachable!(),
1824            };
1825            let element = render_block(block, width, block_id);
1826            block_id += 1;
1827            blocks.push(BlockLayout {
1828                row,
1829                element,
1830                style,
1831            });
1832        }
1833        (
1834            scroll_width.max(fixed_block_max_width - gutter_width),
1835            blocks,
1836        )
1837    }
1838}
1839
1840fn update_inlay_link_and_hover_points(
1841    position_map: &PositionMap,
1842    point_for_position: PointForPosition,
1843    editor: &mut Editor,
1844    (cmd_held, shift_held): (bool, bool),
1845    cx: &mut ViewContext<'_, '_, Editor>,
1846) {
1847    let hint_start_offset = position_map
1848        .snapshot
1849        .display_point_to_inlay_offset(point_for_position.previous_valid, Bias::Left);
1850    let hint_end_offset = position_map
1851        .snapshot
1852        .display_point_to_inlay_offset(point_for_position.next_valid, Bias::Right);
1853    let offset_overshoot = point_for_position.column_overshoot_after_line_end as usize;
1854    let hovered_offset = if offset_overshoot == 0 {
1855        Some(
1856            position_map
1857                .snapshot
1858                .display_point_to_inlay_offset(point_for_position.exact_unclipped, Bias::Left),
1859        )
1860    } else if (hint_end_offset - hint_start_offset).0 >= offset_overshoot {
1861        Some(InlayOffset(hint_start_offset.0 + offset_overshoot))
1862    } else {
1863        None
1864    };
1865    if let Some(hovered_offset) = hovered_offset {
1866        let buffer = editor.buffer().read(cx);
1867        let snapshot = buffer.snapshot(cx);
1868        let previous_valid_anchor = snapshot.anchor_at(
1869            point_for_position
1870                .previous_valid
1871                .to_point(&position_map.snapshot.display_snapshot),
1872            Bias::Left,
1873        );
1874        let next_valid_anchor = snapshot.anchor_at(
1875            point_for_position
1876                .next_valid
1877                .to_point(&position_map.snapshot.display_snapshot),
1878            Bias::Right,
1879        );
1880
1881        let mut go_to_definition_updated = false;
1882        let mut hover_updated = false;
1883        if let Some(hovered_hint) = editor
1884            .visible_inlay_hints(cx)
1885            .into_iter()
1886            .skip_while(|hint| hint.position.cmp(&previous_valid_anchor, &snapshot).is_lt())
1887            .take_while(|hint| hint.position.cmp(&next_valid_anchor, &snapshot).is_le())
1888            .max_by_key(|hint| hint.id)
1889        {
1890            let inlay_hint_cache = editor.inlay_hint_cache();
1891            if let Some(cached_hint) =
1892                inlay_hint_cache.hint_by_id(previous_valid_anchor.excerpt_id, hovered_hint.id)
1893            {
1894                match cached_hint.resolve_state {
1895                    ResolveState::CanResolve(_, _) => {
1896                        if let Some(buffer_id) = previous_valid_anchor.buffer_id {
1897                            inlay_hint_cache.spawn_hint_resolve(
1898                                buffer_id,
1899                                previous_valid_anchor.excerpt_id,
1900                                hovered_hint.id,
1901                                cx,
1902                            );
1903                        }
1904                    }
1905                    ResolveState::Resolved => {
1906                        match cached_hint.label {
1907                            project::InlayHintLabel::String(_) => {
1908                                if cached_hint.tooltip.is_some() {
1909                                    dbg!(&cached_hint.tooltip); // TODO kb
1910                                                                // hover_at_point = Some(hovered_offset);
1911                                }
1912                            }
1913                            project::InlayHintLabel::LabelParts(label_parts) => {
1914                                if let Some(hovered_hint_part) = find_hovered_hint_part(
1915                                    label_parts,
1916                                    hint_start_offset..hint_end_offset,
1917                                    hovered_offset,
1918                                ) {
1919                                    if hovered_hint_part.tooltip.is_some() {
1920                                        dbg!(&hovered_hint_part.tooltip); // TODO kb
1921                                                                          // hover_at_point = Some(hovered_offset);
1922                                    }
1923                                    if let Some(location) = hovered_hint_part.location {
1924                                        if let Some(buffer) = cached_hint
1925                                            .position
1926                                            .buffer_id
1927                                            .and_then(|buffer_id| buffer.buffer(buffer_id))
1928                                        {
1929                                            go_to_definition_updated = true;
1930                                            update_go_to_definition_link(
1931                                                editor,
1932                                                GoToDefinitionTrigger::InlayHint(
1933                                                    hovered_hint.position,
1934                                                    LocationLink {
1935                                                        origin: Some(Location {
1936                                                            buffer,
1937                                                            range: cached_hint.position
1938                                                                ..cached_hint.position,
1939                                                        }),
1940                                                        target: location,
1941                                                    },
1942                                                ),
1943                                                cmd_held,
1944                                                shift_held,
1945                                                cx,
1946                                            );
1947                                        }
1948                                    }
1949                                }
1950                            }
1951                        };
1952                    }
1953                    ResolveState::Resolving => {}
1954                }
1955            }
1956        }
1957
1958        if !go_to_definition_updated {
1959            update_go_to_definition_link(
1960                editor,
1961                GoToDefinitionTrigger::None,
1962                cmd_held,
1963                shift_held,
1964                cx,
1965            );
1966        }
1967        if !hover_updated {
1968            hover_at(editor, None, cx);
1969        }
1970    }
1971}
1972
1973fn find_hovered_hint_part(
1974    label_parts: Vec<InlayHintLabelPart>,
1975    hint_range: Range<InlayOffset>,
1976    hovered_offset: InlayOffset,
1977) -> Option<InlayHintLabelPart> {
1978    if hovered_offset >= hint_range.start && hovered_offset <= hint_range.end {
1979        let mut hovered_character = (hovered_offset - hint_range.start).0;
1980        for part in label_parts {
1981            let part_len = part.value.chars().count();
1982            if hovered_character >= part_len {
1983                hovered_character -= part_len;
1984            } else {
1985                return Some(part);
1986            }
1987        }
1988    }
1989    None
1990}
1991
1992struct HighlightedChunk<'a> {
1993    chunk: &'a str,
1994    style: Option<HighlightStyle>,
1995    is_tab: bool,
1996}
1997
1998#[derive(Debug)]
1999pub struct LineWithInvisibles {
2000    pub line: Line,
2001    invisibles: Vec<Invisible>,
2002}
2003
2004impl LineWithInvisibles {
2005    fn from_chunks<'a>(
2006        chunks: impl Iterator<Item = HighlightedChunk<'a>>,
2007        text_style: &TextStyle,
2008        text_layout_cache: &TextLayoutCache,
2009        font_cache: &Arc<FontCache>,
2010        max_line_len: usize,
2011        max_line_count: usize,
2012        line_number_layouts: &[Option<Line>],
2013        editor_mode: EditorMode,
2014    ) -> Vec<Self> {
2015        let mut layouts = Vec::with_capacity(max_line_count);
2016        let mut line = String::new();
2017        let mut invisibles = Vec::new();
2018        let mut styles = Vec::new();
2019        let mut non_whitespace_added = false;
2020        let mut row = 0;
2021        let mut line_exceeded_max_len = false;
2022        for highlighted_chunk in chunks.chain([HighlightedChunk {
2023            chunk: "\n",
2024            style: None,
2025            is_tab: false,
2026        }]) {
2027            for (ix, mut line_chunk) in highlighted_chunk.chunk.split('\n').enumerate() {
2028                if ix > 0 {
2029                    layouts.push(Self {
2030                        line: text_layout_cache.layout_str(&line, text_style.font_size, &styles),
2031                        invisibles: invisibles.drain(..).collect(),
2032                    });
2033
2034                    line.clear();
2035                    styles.clear();
2036                    row += 1;
2037                    line_exceeded_max_len = false;
2038                    non_whitespace_added = false;
2039                    if row == max_line_count {
2040                        return layouts;
2041                    }
2042                }
2043
2044                if !line_chunk.is_empty() && !line_exceeded_max_len {
2045                    let text_style = if let Some(style) = highlighted_chunk.style {
2046                        text_style
2047                            .clone()
2048                            .highlight(style, font_cache)
2049                            .map(Cow::Owned)
2050                            .unwrap_or_else(|_| Cow::Borrowed(text_style))
2051                    } else {
2052                        Cow::Borrowed(text_style)
2053                    };
2054
2055                    if line.len() + line_chunk.len() > max_line_len {
2056                        let mut chunk_len = max_line_len - line.len();
2057                        while !line_chunk.is_char_boundary(chunk_len) {
2058                            chunk_len -= 1;
2059                        }
2060                        line_chunk = &line_chunk[..chunk_len];
2061                        line_exceeded_max_len = true;
2062                    }
2063
2064                    styles.push((
2065                        line_chunk.len(),
2066                        RunStyle {
2067                            font_id: text_style.font_id,
2068                            color: text_style.color,
2069                            underline: text_style.underline,
2070                        },
2071                    ));
2072
2073                    if editor_mode == EditorMode::Full {
2074                        // Line wrap pads its contents with fake whitespaces,
2075                        // avoid printing them
2076                        let inside_wrapped_string = line_number_layouts
2077                            .get(row)
2078                            .and_then(|layout| layout.as_ref())
2079                            .is_none();
2080                        if highlighted_chunk.is_tab {
2081                            if non_whitespace_added || !inside_wrapped_string {
2082                                invisibles.push(Invisible::Tab {
2083                                    line_start_offset: line.len(),
2084                                });
2085                            }
2086                        } else {
2087                            invisibles.extend(
2088                                line_chunk
2089                                    .chars()
2090                                    .enumerate()
2091                                    .filter(|(_, line_char)| {
2092                                        let is_whitespace = line_char.is_whitespace();
2093                                        non_whitespace_added |= !is_whitespace;
2094                                        is_whitespace
2095                                            && (non_whitespace_added || !inside_wrapped_string)
2096                                    })
2097                                    .map(|(whitespace_index, _)| Invisible::Whitespace {
2098                                        line_offset: line.len() + whitespace_index,
2099                                    }),
2100                            )
2101                        }
2102                    }
2103
2104                    line.push_str(line_chunk);
2105                }
2106            }
2107        }
2108
2109        layouts
2110    }
2111
2112    fn draw(
2113        &self,
2114        layout: &LayoutState,
2115        row: u32,
2116        scroll_top: f32,
2117        scene: &mut SceneBuilder,
2118        content_origin: Vector2F,
2119        scroll_left: f32,
2120        visible_text_bounds: RectF,
2121        whitespace_setting: ShowWhitespaceSetting,
2122        selection_ranges: &[Range<DisplayPoint>],
2123        visible_bounds: RectF,
2124        cx: &mut ViewContext<Editor>,
2125    ) {
2126        let line_height = layout.position_map.line_height;
2127        let line_y = row as f32 * line_height - scroll_top;
2128
2129        self.line.paint(
2130            scene,
2131            content_origin + vec2f(-scroll_left, line_y),
2132            visible_text_bounds,
2133            line_height,
2134            cx,
2135        );
2136
2137        self.draw_invisibles(
2138            &selection_ranges,
2139            layout,
2140            content_origin,
2141            scroll_left,
2142            line_y,
2143            row,
2144            scene,
2145            visible_bounds,
2146            line_height,
2147            whitespace_setting,
2148            cx,
2149        );
2150    }
2151
2152    fn draw_invisibles(
2153        &self,
2154        selection_ranges: &[Range<DisplayPoint>],
2155        layout: &LayoutState,
2156        content_origin: Vector2F,
2157        scroll_left: f32,
2158        line_y: f32,
2159        row: u32,
2160        scene: &mut SceneBuilder,
2161        visible_bounds: RectF,
2162        line_height: f32,
2163        whitespace_setting: ShowWhitespaceSetting,
2164        cx: &mut ViewContext<Editor>,
2165    ) {
2166        let allowed_invisibles_regions = match whitespace_setting {
2167            ShowWhitespaceSetting::None => return,
2168            ShowWhitespaceSetting::Selection => Some(selection_ranges),
2169            ShowWhitespaceSetting::All => None,
2170        };
2171
2172        for invisible in &self.invisibles {
2173            let (&token_offset, invisible_symbol) = match invisible {
2174                Invisible::Tab { line_start_offset } => (line_start_offset, &layout.tab_invisible),
2175                Invisible::Whitespace { line_offset } => (line_offset, &layout.space_invisible),
2176            };
2177
2178            let x_offset = self.line.x_for_index(token_offset);
2179            let invisible_offset =
2180                (layout.position_map.em_width - invisible_symbol.width()).max(0.0) / 2.0;
2181            let origin = content_origin + vec2f(-scroll_left + x_offset + invisible_offset, line_y);
2182
2183            if let Some(allowed_regions) = allowed_invisibles_regions {
2184                let invisible_point = DisplayPoint::new(row, token_offset as u32);
2185                if !allowed_regions
2186                    .iter()
2187                    .any(|region| region.start <= invisible_point && invisible_point < region.end)
2188                {
2189                    continue;
2190                }
2191            }
2192            invisible_symbol.paint(scene, origin, visible_bounds, line_height, cx);
2193        }
2194    }
2195}
2196
2197#[derive(Debug, Clone, Copy, PartialEq, Eq)]
2198enum Invisible {
2199    Tab { line_start_offset: usize },
2200    Whitespace { line_offset: usize },
2201}
2202
2203impl Element<Editor> for EditorElement {
2204    type LayoutState = LayoutState;
2205    type PaintState = ();
2206
2207    fn layout(
2208        &mut self,
2209        constraint: SizeConstraint,
2210        editor: &mut Editor,
2211        cx: &mut LayoutContext<Editor>,
2212    ) -> (Vector2F, Self::LayoutState) {
2213        let mut size = constraint.max;
2214        if size.x().is_infinite() {
2215            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
2216        }
2217
2218        let snapshot = editor.snapshot(cx);
2219        let style = self.style.clone();
2220
2221        let line_height = (style.text.font_size * style.line_height_scalar).round();
2222
2223        let gutter_padding;
2224        let gutter_width;
2225        let gutter_margin;
2226        if snapshot.show_gutter {
2227            let em_width = style.text.em_width(cx.font_cache());
2228            gutter_padding = (em_width * style.gutter_padding_factor).round();
2229            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
2230            gutter_margin = -style.text.descent(cx.font_cache());
2231        } else {
2232            gutter_padding = 0.0;
2233            gutter_width = 0.0;
2234            gutter_margin = 0.0;
2235        };
2236
2237        let text_width = size.x() - gutter_width;
2238        let em_width = style.text.em_width(cx.font_cache());
2239        let em_advance = style.text.em_advance(cx.font_cache());
2240        let overscroll = vec2f(em_width, 0.);
2241        let snapshot = {
2242            editor.set_visible_line_count(size.y() / line_height, cx);
2243
2244            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
2245            let wrap_width = match editor.soft_wrap_mode(cx) {
2246                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
2247                SoftWrap::EditorWidth => editor_width,
2248                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
2249            };
2250
2251            if editor.set_wrap_width(Some(wrap_width), cx) {
2252                editor.snapshot(cx)
2253            } else {
2254                snapshot
2255            }
2256        };
2257
2258        let wrap_guides = editor
2259            .wrap_guides(cx)
2260            .iter()
2261            .map(|(guide, active)| (self.column_pixels(*guide, cx), *active))
2262            .collect();
2263
2264        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
2265        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
2266            size.set_y(
2267                scroll_height
2268                    .min(constraint.max_along(Axis::Vertical))
2269                    .max(constraint.min_along(Axis::Vertical))
2270                    .min(line_height * max_lines as f32),
2271            )
2272        } else if let EditorMode::SingleLine = snapshot.mode {
2273            size.set_y(
2274                line_height
2275                    .min(constraint.max_along(Axis::Vertical))
2276                    .max(constraint.min_along(Axis::Vertical)),
2277            )
2278        } else if size.y().is_infinite() {
2279            size.set_y(scroll_height);
2280        }
2281        let gutter_size = vec2f(gutter_width, size.y());
2282        let text_size = vec2f(text_width, size.y());
2283
2284        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
2285        let mut snapshot = editor.snapshot(cx);
2286
2287        let scroll_position = snapshot.scroll_position();
2288        // The scroll position is a fractional point, the whole number of which represents
2289        // the top of the window in terms of display rows.
2290        let start_row = scroll_position.y() as u32;
2291        let height_in_lines = size.y() / line_height;
2292        let max_row = snapshot.max_point().row();
2293
2294        // Add 1 to ensure selections bleed off screen
2295        let end_row = 1 + cmp::min(
2296            (scroll_position.y() + height_in_lines).ceil() as u32,
2297            max_row,
2298        );
2299
2300        let start_anchor = if start_row == 0 {
2301            Anchor::min()
2302        } else {
2303            snapshot
2304                .buffer_snapshot
2305                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
2306        };
2307        let end_anchor = if end_row > max_row {
2308            Anchor::max()
2309        } else {
2310            snapshot
2311                .buffer_snapshot
2312                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
2313        };
2314
2315        let mut selections: Vec<(Option<ReplicaId>, Vec<SelectionLayout>)> = Vec::new();
2316        let mut active_rows = BTreeMap::new();
2317        let mut fold_ranges = Vec::new();
2318        let is_singleton = editor.is_singleton(cx);
2319
2320        let highlighted_rows = editor.highlighted_rows();
2321        let theme = theme::current(cx);
2322        let highlighted_ranges = editor.background_highlights_in_range(
2323            start_anchor..end_anchor,
2324            &snapshot.display_snapshot,
2325            theme.as_ref(),
2326        );
2327
2328        fold_ranges.extend(
2329            snapshot
2330                .folds_in_range(start_anchor..end_anchor)
2331                .map(|anchor| {
2332                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
2333                    (
2334                        start.row,
2335                        start.to_display_point(&snapshot.display_snapshot)
2336                            ..anchor.end.to_display_point(&snapshot),
2337                    )
2338                }),
2339        );
2340
2341        let mut remote_selections = HashMap::default();
2342        for (replica_id, line_mode, cursor_shape, selection) in snapshot
2343            .buffer_snapshot
2344            .remote_selections_in_range(&(start_anchor..end_anchor))
2345        {
2346            let replica_id = if let Some(mapping) = &editor.replica_id_mapping {
2347                mapping.get(&replica_id).copied()
2348            } else {
2349                None
2350            };
2351
2352            // The local selections match the leader's selections.
2353            if replica_id.is_some() && replica_id == editor.leader_replica_id {
2354                continue;
2355            }
2356            remote_selections
2357                .entry(replica_id)
2358                .or_insert(Vec::new())
2359                .push(SelectionLayout::new(
2360                    selection,
2361                    line_mode,
2362                    cursor_shape,
2363                    &snapshot.display_snapshot,
2364                    false,
2365                    false,
2366                ));
2367        }
2368        selections.extend(remote_selections);
2369
2370        let mut newest_selection_head = None;
2371
2372        if editor.show_local_selections {
2373            let mut local_selections: Vec<Selection<Point>> = editor
2374                .selections
2375                .disjoint_in_range(start_anchor..end_anchor, cx);
2376            local_selections.extend(editor.selections.pending(cx));
2377            let mut layouts = Vec::new();
2378            let newest = editor.selections.newest(cx);
2379            for selection in local_selections.drain(..) {
2380                let is_empty = selection.start == selection.end;
2381                let is_newest = selection == newest;
2382
2383                let layout = SelectionLayout::new(
2384                    selection,
2385                    editor.selections.line_mode,
2386                    editor.cursor_shape,
2387                    &snapshot.display_snapshot,
2388                    is_newest,
2389                    true,
2390                );
2391                if is_newest {
2392                    newest_selection_head = Some(layout.head);
2393                }
2394
2395                for row in cmp::max(layout.active_rows.start, start_row)
2396                    ..=cmp::min(layout.active_rows.end, end_row)
2397                {
2398                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
2399                    *contains_non_empty_selection |= !is_empty;
2400                }
2401                layouts.push(layout);
2402            }
2403
2404            // Render the local selections in the leader's color when following.
2405            let local_replica_id = if let Some(leader_replica_id) = editor.leader_replica_id {
2406                leader_replica_id
2407            } else {
2408                let replica_id = editor.replica_id(cx);
2409                if let Some(mapping) = &editor.replica_id_mapping {
2410                    mapping.get(&replica_id).copied().unwrap_or(replica_id)
2411                } else {
2412                    replica_id
2413                }
2414            };
2415
2416            selections.push((Some(local_replica_id), layouts));
2417        }
2418
2419        let scrollbar_settings = &settings::get::<EditorSettings>(cx).scrollbar;
2420        let show_scrollbars = match scrollbar_settings.show {
2421            ShowScrollbar::Auto => {
2422                // Git
2423                (is_singleton && scrollbar_settings.git_diff && snapshot.buffer_snapshot.has_git_diffs())
2424                ||
2425                // Selections
2426                (is_singleton && scrollbar_settings.selections && !highlighted_ranges.is_empty())
2427                // Scrollmanager
2428                || editor.scroll_manager.scrollbars_visible()
2429            }
2430            ShowScrollbar::System => editor.scroll_manager.scrollbars_visible(),
2431            ShowScrollbar::Always => true,
2432            ShowScrollbar::Never => false,
2433        };
2434
2435        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
2436            .into_iter()
2437            .map(|(id, fold)| {
2438                let color = self
2439                    .style
2440                    .folds
2441                    .ellipses
2442                    .background
2443                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize))
2444                    .color;
2445
2446                (id, fold, color)
2447            })
2448            .collect();
2449
2450        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
2451            start_row..end_row,
2452            &active_rows,
2453            is_singleton,
2454            &snapshot,
2455            cx,
2456        );
2457
2458        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
2459
2460        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
2461
2462        let mut max_visible_line_width = 0.0;
2463        let line_layouts =
2464            self.layout_lines(start_row..end_row, &line_number_layouts, &snapshot, cx);
2465        for line_with_invisibles in &line_layouts {
2466            if line_with_invisibles.line.width() > max_visible_line_width {
2467                max_visible_line_width = line_with_invisibles.line.width();
2468            }
2469        }
2470
2471        let style = self.style.clone();
2472        let longest_line_width = layout_line(
2473            snapshot.longest_row(),
2474            &snapshot,
2475            &style,
2476            cx.text_layout_cache(),
2477        )
2478        .width();
2479        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
2480        let em_width = style.text.em_width(cx.font_cache());
2481        let (scroll_width, blocks) = self.layout_blocks(
2482            start_row..end_row,
2483            &snapshot,
2484            size.x(),
2485            scroll_width,
2486            gutter_padding,
2487            gutter_width,
2488            em_width,
2489            gutter_width + gutter_margin,
2490            line_height,
2491            &style,
2492            &line_layouts,
2493            editor,
2494            cx,
2495        );
2496
2497        let scroll_max = vec2f(
2498            ((scroll_width - text_size.x()) / em_width).max(0.0),
2499            max_row as f32,
2500        );
2501
2502        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
2503
2504        let autoscrolled = if autoscroll_horizontally {
2505            editor.autoscroll_horizontally(
2506                start_row,
2507                text_size.x(),
2508                scroll_width,
2509                em_width,
2510                &line_layouts,
2511                cx,
2512            )
2513        } else {
2514            false
2515        };
2516
2517        if clamped || autoscrolled {
2518            snapshot = editor.snapshot(cx);
2519        }
2520
2521        let style = editor.style(cx);
2522
2523        let mut context_menu = None;
2524        let mut code_actions_indicator = None;
2525        if let Some(newest_selection_head) = newest_selection_head {
2526            if (start_row..end_row).contains(&newest_selection_head.row()) {
2527                if editor.context_menu_visible() {
2528                    context_menu =
2529                        editor.render_context_menu(newest_selection_head, style.clone(), cx);
2530                }
2531
2532                let active = matches!(
2533                    editor.context_menu,
2534                    Some(crate::ContextMenu::CodeActions(_))
2535                );
2536
2537                code_actions_indicator = editor
2538                    .render_code_actions_indicator(&style, active, cx)
2539                    .map(|indicator| (newest_selection_head.row(), indicator));
2540            }
2541        }
2542
2543        let visible_rows = start_row..start_row + line_layouts.len() as u32;
2544        let mut hover = editor
2545            .hover_state
2546            .render(&snapshot, &style, visible_rows, cx);
2547        let mode = editor.mode;
2548
2549        let mut fold_indicators = editor.render_fold_indicators(
2550            fold_statuses,
2551            &style,
2552            editor.gutter_hovered,
2553            line_height,
2554            gutter_margin,
2555            cx,
2556        );
2557
2558        if let Some((_, context_menu)) = context_menu.as_mut() {
2559            context_menu.layout(
2560                SizeConstraint {
2561                    min: Vector2F::zero(),
2562                    max: vec2f(
2563                        cx.window_size().x() * 0.7,
2564                        (12. * line_height).min((size.y() - line_height) / 2.),
2565                    ),
2566                },
2567                editor,
2568                cx,
2569            );
2570        }
2571
2572        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
2573            indicator.layout(
2574                SizeConstraint::strict_along(
2575                    Axis::Vertical,
2576                    line_height * style.code_actions.vertical_scale,
2577                ),
2578                editor,
2579                cx,
2580            );
2581        }
2582
2583        for fold_indicator in fold_indicators.iter_mut() {
2584            if let Some(indicator) = fold_indicator.as_mut() {
2585                indicator.layout(
2586                    SizeConstraint::strict_along(
2587                        Axis::Vertical,
2588                        line_height * style.code_actions.vertical_scale,
2589                    ),
2590                    editor,
2591                    cx,
2592                );
2593            }
2594        }
2595
2596        if let Some((_, hover_popovers)) = hover.as_mut() {
2597            for hover_popover in hover_popovers.iter_mut() {
2598                hover_popover.layout(
2599                    SizeConstraint {
2600                        min: Vector2F::zero(),
2601                        max: vec2f(
2602                            (120. * em_width) // Default size
2603                                .min(size.x() / 2.) // Shrink to half of the editor width
2604                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
2605                            (16. * line_height) // Default size
2606                                .min(size.y() / 2.) // Shrink to half of the editor height
2607                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
2608                        ),
2609                    },
2610                    editor,
2611                    cx,
2612                );
2613            }
2614        }
2615
2616        let invisible_symbol_font_size = self.style.text.font_size / 2.0;
2617        let invisible_symbol_style = RunStyle {
2618            color: self.style.whitespace,
2619            font_id: self.style.text.font_id,
2620            underline: Default::default(),
2621        };
2622
2623        (
2624            size,
2625            LayoutState {
2626                mode,
2627                position_map: Arc::new(PositionMap {
2628                    size,
2629                    scroll_max,
2630                    line_layouts,
2631                    line_height,
2632                    em_width,
2633                    em_advance,
2634                    snapshot,
2635                }),
2636                visible_display_row_range: start_row..end_row,
2637                wrap_guides,
2638                gutter_size,
2639                gutter_padding,
2640                text_size,
2641                scrollbar_row_range,
2642                show_scrollbars,
2643                is_singleton,
2644                max_row,
2645                gutter_margin,
2646                active_rows,
2647                highlighted_rows,
2648                highlighted_ranges,
2649                fold_ranges,
2650                line_number_layouts,
2651                display_hunks,
2652                blocks,
2653                selections,
2654                context_menu,
2655                code_actions_indicator,
2656                fold_indicators,
2657                tab_invisible: cx.text_layout_cache().layout_str(
2658                    "",
2659                    invisible_symbol_font_size,
2660                    &[("".len(), invisible_symbol_style)],
2661                ),
2662                space_invisible: cx.text_layout_cache().layout_str(
2663                    "",
2664                    invisible_symbol_font_size,
2665                    &[("".len(), invisible_symbol_style)],
2666                ),
2667                hover_popovers: hover,
2668            },
2669        )
2670    }
2671
2672    fn paint(
2673        &mut self,
2674        scene: &mut SceneBuilder,
2675        bounds: RectF,
2676        visible_bounds: RectF,
2677        layout: &mut Self::LayoutState,
2678        editor: &mut Editor,
2679        cx: &mut PaintContext<Editor>,
2680    ) -> Self::PaintState {
2681        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2682        scene.push_layer(Some(visible_bounds));
2683
2684        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2685        let text_bounds = RectF::new(
2686            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2687            layout.text_size,
2688        );
2689
2690        Self::attach_mouse_handlers(
2691            scene,
2692            &layout.position_map,
2693            layout.hover_popovers.is_some(),
2694            visible_bounds,
2695            text_bounds,
2696            gutter_bounds,
2697            bounds,
2698            cx,
2699        );
2700
2701        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2702        if layout.gutter_size.x() > 0. {
2703            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2704        }
2705        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2706
2707        scene.push_layer(Some(bounds));
2708        if !layout.blocks.is_empty() {
2709            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2710        }
2711        self.paint_scrollbar(scene, bounds, layout, cx, &editor);
2712        scene.pop_layer();
2713
2714        scene.pop_layer();
2715    }
2716
2717    fn rect_for_text_range(
2718        &self,
2719        range_utf16: Range<usize>,
2720        bounds: RectF,
2721        _: RectF,
2722        layout: &Self::LayoutState,
2723        _: &Self::PaintState,
2724        _: &Editor,
2725        _: &ViewContext<Editor>,
2726    ) -> Option<RectF> {
2727        let text_bounds = RectF::new(
2728            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2729            layout.text_size,
2730        );
2731        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2732        let scroll_position = layout.position_map.snapshot.scroll_position();
2733        let start_row = scroll_position.y() as u32;
2734        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2735        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2736
2737        let range_start = OffsetUtf16(range_utf16.start)
2738            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2739        if range_start.row() < start_row {
2740            return None;
2741        }
2742
2743        let line = &layout
2744            .position_map
2745            .line_layouts
2746            .get((range_start.row() - start_row) as usize)?
2747            .line;
2748        let range_start_x = line.x_for_index(range_start.column() as usize);
2749        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2750        Some(RectF::new(
2751            content_origin
2752                + vec2f(
2753                    range_start_x,
2754                    range_start_y + layout.position_map.line_height,
2755                )
2756                - vec2f(scroll_left, scroll_top),
2757            vec2f(
2758                layout.position_map.em_width,
2759                layout.position_map.line_height,
2760            ),
2761        ))
2762    }
2763
2764    fn debug(
2765        &self,
2766        bounds: RectF,
2767        _: &Self::LayoutState,
2768        _: &Self::PaintState,
2769        _: &Editor,
2770        _: &ViewContext<Editor>,
2771    ) -> json::Value {
2772        json!({
2773            "type": "BufferElement",
2774            "bounds": bounds.to_json()
2775        })
2776    }
2777}
2778
2779type BufferRow = u32;
2780
2781pub struct LayoutState {
2782    position_map: Arc<PositionMap>,
2783    gutter_size: Vector2F,
2784    gutter_padding: f32,
2785    gutter_margin: f32,
2786    text_size: Vector2F,
2787    mode: EditorMode,
2788    wrap_guides: SmallVec<[(f32, bool); 2]>,
2789    visible_display_row_range: Range<u32>,
2790    active_rows: BTreeMap<u32, bool>,
2791    highlighted_rows: Option<Range<u32>>,
2792    line_number_layouts: Vec<Option<text_layout::Line>>,
2793    display_hunks: Vec<DisplayDiffHunk>,
2794    blocks: Vec<BlockLayout>,
2795    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2796    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2797    selections: Vec<(Option<ReplicaId>, Vec<SelectionLayout>)>,
2798    scrollbar_row_range: Range<f32>,
2799    show_scrollbars: bool,
2800    is_singleton: bool,
2801    max_row: u32,
2802    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2803    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2804    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2805    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2806    tab_invisible: Line,
2807    space_invisible: Line,
2808}
2809
2810struct PositionMap {
2811    size: Vector2F,
2812    line_height: f32,
2813    scroll_max: Vector2F,
2814    em_width: f32,
2815    em_advance: f32,
2816    line_layouts: Vec<LineWithInvisibles>,
2817    snapshot: EditorSnapshot,
2818}
2819
2820#[derive(Debug)]
2821struct PointForPosition {
2822    previous_valid: DisplayPoint,
2823    next_valid: DisplayPoint,
2824    exact_unclipped: DisplayPoint,
2825    column_overshoot_after_line_end: u32,
2826}
2827
2828impl PointForPosition {
2829    fn as_valid(&self) -> Option<DisplayPoint> {
2830        if self.previous_valid == self.exact_unclipped && self.next_valid == self.exact_unclipped {
2831            Some(self.previous_valid)
2832        } else {
2833            None
2834        }
2835    }
2836}
2837
2838impl PositionMap {
2839    fn point_for_position(&self, text_bounds: RectF, position: Vector2F) -> PointForPosition {
2840        let scroll_position = self.snapshot.scroll_position();
2841        let position = position - text_bounds.origin();
2842        let y = position.y().max(0.0).min(self.size.y());
2843        let x = position.x() + (scroll_position.x() * self.em_width);
2844        let row = (y / self.line_height + scroll_position.y()) as u32;
2845        let (column, x_overshoot_after_line_end) = if let Some(line) = self
2846            .line_layouts
2847            .get(row as usize - scroll_position.y() as usize)
2848            .map(|line_with_spaces| &line_with_spaces.line)
2849        {
2850            if let Some(ix) = line.index_for_x(x) {
2851                (ix as u32, 0.0)
2852            } else {
2853                (line.len() as u32, 0f32.max(x - line.width()))
2854            }
2855        } else {
2856            (0, x)
2857        };
2858
2859        let mut exact_unclipped = DisplayPoint::new(row, column);
2860        let previous_valid = self.snapshot.clip_point(exact_unclipped, Bias::Left);
2861        let next_valid = self.snapshot.clip_point(exact_unclipped, Bias::Right);
2862
2863        let column_overshoot_after_line_end = (x_overshoot_after_line_end / self.em_advance) as u32;
2864        *exact_unclipped.column_mut() += column_overshoot_after_line_end;
2865        PointForPosition {
2866            previous_valid,
2867            next_valid,
2868            exact_unclipped,
2869            column_overshoot_after_line_end,
2870        }
2871    }
2872}
2873
2874struct BlockLayout {
2875    row: u32,
2876    element: AnyElement<Editor>,
2877    style: BlockStyle,
2878}
2879
2880fn layout_line(
2881    row: u32,
2882    snapshot: &EditorSnapshot,
2883    style: &EditorStyle,
2884    layout_cache: &TextLayoutCache,
2885) -> text_layout::Line {
2886    let mut line = snapshot.line(row);
2887
2888    if line.len() > MAX_LINE_LEN {
2889        let mut len = MAX_LINE_LEN;
2890        while !line.is_char_boundary(len) {
2891            len -= 1;
2892        }
2893
2894        line.truncate(len);
2895    }
2896
2897    layout_cache.layout_str(
2898        &line,
2899        style.text.font_size,
2900        &[(
2901            snapshot.line_len(row) as usize,
2902            RunStyle {
2903                font_id: style.text.font_id,
2904                color: Color::black(),
2905                underline: Default::default(),
2906            },
2907        )],
2908    )
2909}
2910
2911#[derive(Debug)]
2912pub struct Cursor {
2913    origin: Vector2F,
2914    block_width: f32,
2915    line_height: f32,
2916    color: Color,
2917    shape: CursorShape,
2918    block_text: Option<Line>,
2919}
2920
2921impl Cursor {
2922    pub fn new(
2923        origin: Vector2F,
2924        block_width: f32,
2925        line_height: f32,
2926        color: Color,
2927        shape: CursorShape,
2928        block_text: Option<Line>,
2929    ) -> Cursor {
2930        Cursor {
2931            origin,
2932            block_width,
2933            line_height,
2934            color,
2935            shape,
2936            block_text,
2937        }
2938    }
2939
2940    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2941        RectF::new(
2942            self.origin + origin,
2943            vec2f(self.block_width, self.line_height),
2944        )
2945    }
2946
2947    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2948        let bounds = match self.shape {
2949            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2950            CursorShape::Block | CursorShape::Hollow => RectF::new(
2951                self.origin + origin,
2952                vec2f(self.block_width, self.line_height),
2953            ),
2954            CursorShape::Underscore => RectF::new(
2955                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2956                vec2f(self.block_width, 2.0),
2957            ),
2958        };
2959
2960        //Draw background or border quad
2961        if matches!(self.shape, CursorShape::Hollow) {
2962            scene.push_quad(Quad {
2963                bounds,
2964                background: None,
2965                border: Border::all(1., self.color),
2966                corner_radii: Default::default(),
2967            });
2968        } else {
2969            scene.push_quad(Quad {
2970                bounds,
2971                background: Some(self.color),
2972                border: Default::default(),
2973                corner_radii: Default::default(),
2974            });
2975        }
2976
2977        if let Some(block_text) = &self.block_text {
2978            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2979        }
2980    }
2981
2982    pub fn shape(&self) -> CursorShape {
2983        self.shape
2984    }
2985}
2986
2987#[derive(Debug)]
2988pub struct HighlightedRange {
2989    pub start_y: f32,
2990    pub line_height: f32,
2991    pub lines: Vec<HighlightedRangeLine>,
2992    pub color: Color,
2993    pub corner_radius: f32,
2994}
2995
2996#[derive(Debug)]
2997pub struct HighlightedRangeLine {
2998    pub start_x: f32,
2999    pub end_x: f32,
3000}
3001
3002impl HighlightedRange {
3003    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
3004        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
3005            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
3006            self.paint_lines(
3007                self.start_y + self.line_height,
3008                &self.lines[1..],
3009                bounds,
3010                scene,
3011            );
3012        } else {
3013            self.paint_lines(self.start_y, &self.lines, bounds, scene);
3014        }
3015    }
3016
3017    fn paint_lines(
3018        &self,
3019        start_y: f32,
3020        lines: &[HighlightedRangeLine],
3021        bounds: RectF,
3022        scene: &mut SceneBuilder,
3023    ) {
3024        if lines.is_empty() {
3025            return;
3026        }
3027
3028        let mut path = PathBuilder::new();
3029        let first_line = lines.first().unwrap();
3030        let last_line = lines.last().unwrap();
3031
3032        let first_top_left = vec2f(first_line.start_x, start_y);
3033        let first_top_right = vec2f(first_line.end_x, start_y);
3034
3035        let curve_height = vec2f(0., self.corner_radius);
3036        let curve_width = |start_x: f32, end_x: f32| {
3037            let max = (end_x - start_x) / 2.;
3038            let width = if max < self.corner_radius {
3039                max
3040            } else {
3041                self.corner_radius
3042            };
3043
3044            vec2f(width, 0.)
3045        };
3046
3047        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
3048        path.reset(first_top_right - top_curve_width);
3049        path.curve_to(first_top_right + curve_height, first_top_right);
3050
3051        let mut iter = lines.iter().enumerate().peekable();
3052        while let Some((ix, line)) = iter.next() {
3053            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
3054
3055            if let Some((_, next_line)) = iter.peek() {
3056                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
3057
3058                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
3059                    Ordering::Equal => {
3060                        path.line_to(bottom_right);
3061                    }
3062                    Ordering::Less => {
3063                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
3064                        path.line_to(bottom_right - curve_height);
3065                        if self.corner_radius > 0. {
3066                            path.curve_to(bottom_right - curve_width, bottom_right);
3067                        }
3068                        path.line_to(next_top_right + curve_width);
3069                        if self.corner_radius > 0. {
3070                            path.curve_to(next_top_right + curve_height, next_top_right);
3071                        }
3072                    }
3073                    Ordering::Greater => {
3074                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
3075                        path.line_to(bottom_right - curve_height);
3076                        if self.corner_radius > 0. {
3077                            path.curve_to(bottom_right + curve_width, bottom_right);
3078                        }
3079                        path.line_to(next_top_right - curve_width);
3080                        if self.corner_radius > 0. {
3081                            path.curve_to(next_top_right + curve_height, next_top_right);
3082                        }
3083                    }
3084                }
3085            } else {
3086                let curve_width = curve_width(line.start_x, line.end_x);
3087                path.line_to(bottom_right - curve_height);
3088                if self.corner_radius > 0. {
3089                    path.curve_to(bottom_right - curve_width, bottom_right);
3090                }
3091
3092                let bottom_left = vec2f(line.start_x, bottom_right.y());
3093                path.line_to(bottom_left + curve_width);
3094                if self.corner_radius > 0. {
3095                    path.curve_to(bottom_left - curve_height, bottom_left);
3096                }
3097            }
3098        }
3099
3100        if first_line.start_x > last_line.start_x {
3101            let curve_width = curve_width(last_line.start_x, first_line.start_x);
3102            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
3103            path.line_to(second_top_left + curve_height);
3104            if self.corner_radius > 0. {
3105                path.curve_to(second_top_left + curve_width, second_top_left);
3106            }
3107            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
3108            path.line_to(first_bottom_left - curve_width);
3109            if self.corner_radius > 0. {
3110                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
3111            }
3112        }
3113
3114        path.line_to(first_top_left + curve_height);
3115        if self.corner_radius > 0. {
3116            path.curve_to(first_top_left + top_curve_width, first_top_left);
3117        }
3118        path.line_to(first_top_right - top_curve_width);
3119
3120        scene.push_path(path.build(self.color, Some(bounds)));
3121    }
3122}
3123
3124fn range_to_bounds(
3125    range: &Range<DisplayPoint>,
3126    content_origin: Vector2F,
3127    scroll_left: f32,
3128    scroll_top: f32,
3129    visible_row_range: &Range<u32>,
3130    line_end_overshoot: f32,
3131    position_map: &PositionMap,
3132) -> impl Iterator<Item = RectF> {
3133    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
3134
3135    if range.start == range.end {
3136        return bounds.into_iter();
3137    }
3138
3139    let start_row = visible_row_range.start;
3140    let end_row = visible_row_range.end;
3141
3142    let row_range = if range.end.column() == 0 {
3143        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
3144    } else {
3145        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
3146    };
3147
3148    let first_y =
3149        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
3150
3151    for (idx, row) in row_range.enumerate() {
3152        let line_layout = &position_map.line_layouts[(row - start_row) as usize].line;
3153
3154        let start_x = if row == range.start.row() {
3155            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
3156                - scroll_left
3157        } else {
3158            content_origin.x() - scroll_left
3159        };
3160
3161        let end_x = if row == range.end.row() {
3162            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
3163        } else {
3164            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
3165        };
3166
3167        bounds.push(RectF::from_points(
3168            vec2f(start_x, first_y + position_map.line_height * idx as f32),
3169            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
3170        ))
3171    }
3172
3173    bounds.into_iter()
3174}
3175
3176pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
3177    delta.powf(1.5) / 100.0
3178}
3179
3180fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
3181    delta.powf(1.2) / 300.0
3182}
3183
3184#[cfg(test)]
3185mod tests {
3186    use super::*;
3187    use crate::{
3188        display_map::{BlockDisposition, BlockProperties},
3189        editor_tests::{init_test, update_test_language_settings},
3190        Editor, MultiBuffer,
3191    };
3192    use gpui::TestAppContext;
3193    use language::language_settings;
3194    use log::info;
3195    use std::{num::NonZeroU32, sync::Arc};
3196    use util::test::sample_text;
3197
3198    #[gpui::test]
3199    fn test_layout_line_numbers(cx: &mut TestAppContext) {
3200        init_test(cx, |_| {});
3201
3202        let editor = cx
3203            .add_window(|cx| {
3204                let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
3205                Editor::new(EditorMode::Full, buffer, None, None, cx)
3206            })
3207            .root(cx);
3208        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3209
3210        let layouts = editor.update(cx, |editor, cx| {
3211            let snapshot = editor.snapshot(cx);
3212            element
3213                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
3214                .0
3215        });
3216        assert_eq!(layouts.len(), 6);
3217    }
3218
3219    #[gpui::test]
3220    async fn test_vim_visual_selections(cx: &mut TestAppContext) {
3221        init_test(cx, |_| {});
3222
3223        let editor = cx
3224            .add_window(|cx| {
3225                let buffer = MultiBuffer::build_simple(&(sample_text(6, 6, 'a') + "\n"), cx);
3226                Editor::new(EditorMode::Full, buffer, None, None, cx)
3227            })
3228            .root(cx);
3229        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3230        let (_, state) = editor.update(cx, |editor, cx| {
3231            editor.cursor_shape = CursorShape::Block;
3232            editor.change_selections(None, cx, |s| {
3233                s.select_ranges([
3234                    Point::new(0, 0)..Point::new(1, 0),
3235                    Point::new(3, 2)..Point::new(3, 3),
3236                    Point::new(5, 6)..Point::new(6, 0),
3237                ]);
3238            });
3239            let mut new_parents = Default::default();
3240            let mut notify_views_if_parents_change = Default::default();
3241            let mut layout_cx = LayoutContext::new(
3242                cx,
3243                &mut new_parents,
3244                &mut notify_views_if_parents_change,
3245                false,
3246            );
3247            element.layout(
3248                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3249                editor,
3250                &mut layout_cx,
3251            )
3252        });
3253        assert_eq!(state.selections.len(), 1);
3254        let local_selections = &state.selections[0].1;
3255        assert_eq!(local_selections.len(), 3);
3256        // moves cursor back one line
3257        assert_eq!(local_selections[0].head, DisplayPoint::new(0, 6));
3258        assert_eq!(
3259            local_selections[0].range,
3260            DisplayPoint::new(0, 0)..DisplayPoint::new(1, 0)
3261        );
3262
3263        // moves cursor back one column
3264        assert_eq!(
3265            local_selections[1].range,
3266            DisplayPoint::new(3, 2)..DisplayPoint::new(3, 3)
3267        );
3268        assert_eq!(local_selections[1].head, DisplayPoint::new(3, 2));
3269
3270        // leaves cursor on the max point
3271        assert_eq!(
3272            local_selections[2].range,
3273            DisplayPoint::new(5, 6)..DisplayPoint::new(6, 0)
3274        );
3275        assert_eq!(local_selections[2].head, DisplayPoint::new(6, 0));
3276
3277        // active lines does not include 1 (even though the range of the selection does)
3278        assert_eq!(
3279            state.active_rows.keys().cloned().collect::<Vec<u32>>(),
3280            vec![0, 3, 5, 6]
3281        );
3282
3283        // multi-buffer support
3284        // in DisplayPoint co-ordinates, this is what we're dealing with:
3285        //  0: [[file
3286        //  1:   header]]
3287        //  2: aaaaaa
3288        //  3: bbbbbb
3289        //  4: cccccc
3290        //  5:
3291        //  6: ...
3292        //  7: ffffff
3293        //  8: gggggg
3294        //  9: hhhhhh
3295        // 10:
3296        // 11: [[file
3297        // 12:   header]]
3298        // 13: bbbbbb
3299        // 14: cccccc
3300        // 15: dddddd
3301        let editor = cx
3302            .add_window(|cx| {
3303                let buffer = MultiBuffer::build_multi(
3304                    [
3305                        (
3306                            &(sample_text(8, 6, 'a') + "\n"),
3307                            vec![
3308                                Point::new(0, 0)..Point::new(3, 0),
3309                                Point::new(4, 0)..Point::new(7, 0),
3310                            ],
3311                        ),
3312                        (
3313                            &(sample_text(8, 6, 'a') + "\n"),
3314                            vec![Point::new(1, 0)..Point::new(3, 0)],
3315                        ),
3316                    ],
3317                    cx,
3318                );
3319                Editor::new(EditorMode::Full, buffer, None, None, cx)
3320            })
3321            .root(cx);
3322        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3323        let (_, state) = editor.update(cx, |editor, cx| {
3324            editor.cursor_shape = CursorShape::Block;
3325            editor.change_selections(None, cx, |s| {
3326                s.select_display_ranges([
3327                    DisplayPoint::new(4, 0)..DisplayPoint::new(7, 0),
3328                    DisplayPoint::new(10, 0)..DisplayPoint::new(13, 0),
3329                ]);
3330            });
3331            let mut new_parents = Default::default();
3332            let mut notify_views_if_parents_change = Default::default();
3333            let mut layout_cx = LayoutContext::new(
3334                cx,
3335                &mut new_parents,
3336                &mut notify_views_if_parents_change,
3337                false,
3338            );
3339            element.layout(
3340                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3341                editor,
3342                &mut layout_cx,
3343            )
3344        });
3345
3346        assert_eq!(state.selections.len(), 1);
3347        let local_selections = &state.selections[0].1;
3348        assert_eq!(local_selections.len(), 2);
3349
3350        // moves cursor on excerpt boundary back a line
3351        // and doesn't allow selection to bleed through
3352        assert_eq!(
3353            local_selections[0].range,
3354            DisplayPoint::new(4, 0)..DisplayPoint::new(6, 0)
3355        );
3356        assert_eq!(local_selections[0].head, DisplayPoint::new(5, 0));
3357
3358        // moves cursor on buffer boundary back two lines
3359        // and doesn't allow selection to bleed through
3360        assert_eq!(
3361            local_selections[1].range,
3362            DisplayPoint::new(10, 0)..DisplayPoint::new(11, 0)
3363        );
3364        assert_eq!(local_selections[1].head, DisplayPoint::new(10, 0));
3365    }
3366
3367    #[gpui::test]
3368    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
3369        init_test(cx, |_| {});
3370
3371        let editor = cx
3372            .add_window(|cx| {
3373                let buffer = MultiBuffer::build_simple("", cx);
3374                Editor::new(EditorMode::Full, buffer, None, None, cx)
3375            })
3376            .root(cx);
3377
3378        editor.update(cx, |editor, cx| {
3379            editor.set_placeholder_text("hello", cx);
3380            editor.insert_blocks(
3381                [BlockProperties {
3382                    style: BlockStyle::Fixed,
3383                    disposition: BlockDisposition::Above,
3384                    height: 3,
3385                    position: Anchor::min(),
3386                    render: Arc::new(|_| Empty::new().into_any()),
3387                }],
3388                None,
3389                cx,
3390            );
3391
3392            // Blur the editor so that it displays placeholder text.
3393            cx.blur();
3394        });
3395
3396        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3397        let (size, mut state) = editor.update(cx, |editor, cx| {
3398            let mut new_parents = Default::default();
3399            let mut notify_views_if_parents_change = Default::default();
3400            let mut layout_cx = LayoutContext::new(
3401                cx,
3402                &mut new_parents,
3403                &mut notify_views_if_parents_change,
3404                false,
3405            );
3406            element.layout(
3407                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3408                editor,
3409                &mut layout_cx,
3410            )
3411        });
3412
3413        assert_eq!(state.position_map.line_layouts.len(), 4);
3414        assert_eq!(
3415            state
3416                .line_number_layouts
3417                .iter()
3418                .map(Option::is_some)
3419                .collect::<Vec<_>>(),
3420            &[false, false, false, true]
3421        );
3422
3423        // Don't panic.
3424        let mut scene = SceneBuilder::new(1.0);
3425        let bounds = RectF::new(Default::default(), size);
3426        editor.update(cx, |editor, cx| {
3427            element.paint(
3428                &mut scene,
3429                bounds,
3430                bounds,
3431                &mut state,
3432                editor,
3433                &mut PaintContext::new(cx),
3434            );
3435        });
3436    }
3437
3438    #[gpui::test]
3439    fn test_all_invisibles_drawing(cx: &mut TestAppContext) {
3440        const TAB_SIZE: u32 = 4;
3441
3442        let input_text = "\t \t|\t| a b";
3443        let expected_invisibles = vec![
3444            Invisible::Tab {
3445                line_start_offset: 0,
3446            },
3447            Invisible::Whitespace {
3448                line_offset: TAB_SIZE as usize,
3449            },
3450            Invisible::Tab {
3451                line_start_offset: TAB_SIZE as usize + 1,
3452            },
3453            Invisible::Tab {
3454                line_start_offset: TAB_SIZE as usize * 2 + 1,
3455            },
3456            Invisible::Whitespace {
3457                line_offset: TAB_SIZE as usize * 3 + 1,
3458            },
3459            Invisible::Whitespace {
3460                line_offset: TAB_SIZE as usize * 3 + 3,
3461            },
3462        ];
3463        assert_eq!(
3464            expected_invisibles.len(),
3465            input_text
3466                .chars()
3467                .filter(|initial_char| initial_char.is_whitespace())
3468                .count(),
3469            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3470        );
3471
3472        init_test(cx, |s| {
3473            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3474            s.defaults.tab_size = NonZeroU32::new(TAB_SIZE);
3475        });
3476
3477        let actual_invisibles =
3478            collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, 500.0);
3479
3480        assert_eq!(expected_invisibles, actual_invisibles);
3481    }
3482
3483    #[gpui::test]
3484    fn test_invisibles_dont_appear_in_certain_editors(cx: &mut TestAppContext) {
3485        init_test(cx, |s| {
3486            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3487            s.defaults.tab_size = NonZeroU32::new(4);
3488        });
3489
3490        for editor_mode_without_invisibles in [
3491            EditorMode::SingleLine,
3492            EditorMode::AutoHeight { max_lines: 100 },
3493        ] {
3494            let invisibles = collect_invisibles_from_new_editor(
3495                cx,
3496                editor_mode_without_invisibles,
3497                "\t\t\t| | a b",
3498                500.0,
3499            );
3500            assert!(invisibles.is_empty(),
3501                "For editor mode {editor_mode_without_invisibles:?} no invisibles was expected but got {invisibles:?}");
3502        }
3503    }
3504
3505    #[gpui::test]
3506    fn test_wrapped_invisibles_drawing(cx: &mut TestAppContext) {
3507        let tab_size = 4;
3508        let input_text = "a\tbcd   ".repeat(9);
3509        let repeated_invisibles = [
3510            Invisible::Tab {
3511                line_start_offset: 1,
3512            },
3513            Invisible::Whitespace {
3514                line_offset: tab_size as usize + 3,
3515            },
3516            Invisible::Whitespace {
3517                line_offset: tab_size as usize + 4,
3518            },
3519            Invisible::Whitespace {
3520                line_offset: tab_size as usize + 5,
3521            },
3522        ];
3523        let expected_invisibles = std::iter::once(repeated_invisibles)
3524            .cycle()
3525            .take(9)
3526            .flatten()
3527            .collect::<Vec<_>>();
3528        assert_eq!(
3529            expected_invisibles.len(),
3530            input_text
3531                .chars()
3532                .filter(|initial_char| initial_char.is_whitespace())
3533                .count(),
3534            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3535        );
3536        info!("Expected invisibles: {expected_invisibles:?}");
3537
3538        init_test(cx, |_| {});
3539
3540        // Put the same string with repeating whitespace pattern into editors of various size,
3541        // take deliberately small steps during resizing, to put all whitespace kinds near the wrap point.
3542        let resize_step = 10.0;
3543        let mut editor_width = 200.0;
3544        while editor_width <= 1000.0 {
3545            update_test_language_settings(cx, |s| {
3546                s.defaults.tab_size = NonZeroU32::new(tab_size);
3547                s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3548                s.defaults.preferred_line_length = Some(editor_width as u32);
3549                s.defaults.soft_wrap = Some(language_settings::SoftWrap::PreferredLineLength);
3550            });
3551
3552            let actual_invisibles =
3553                collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, editor_width);
3554
3555            // Whatever the editor size is, ensure it has the same invisible kinds in the same order
3556            // (no good guarantees about the offsets: wrapping could trigger padding and its tests should check the offsets).
3557            let mut i = 0;
3558            for (actual_index, actual_invisible) in actual_invisibles.iter().enumerate() {
3559                i = actual_index;
3560                match expected_invisibles.get(i) {
3561                    Some(expected_invisible) => match (expected_invisible, actual_invisible) {
3562                        (Invisible::Whitespace { .. }, Invisible::Whitespace { .. })
3563                        | (Invisible::Tab { .. }, Invisible::Tab { .. }) => {}
3564                        _ => {
3565                            panic!("At index {i}, expected invisible {expected_invisible:?} does not match actual {actual_invisible:?} by kind. Actual invisibles: {actual_invisibles:?}")
3566                        }
3567                    },
3568                    None => panic!("Unexpected extra invisible {actual_invisible:?} at index {i}"),
3569                }
3570            }
3571            let missing_expected_invisibles = &expected_invisibles[i + 1..];
3572            assert!(
3573                missing_expected_invisibles.is_empty(),
3574                "Missing expected invisibles after index {i}: {missing_expected_invisibles:?}"
3575            );
3576
3577            editor_width += resize_step;
3578        }
3579    }
3580
3581    fn collect_invisibles_from_new_editor(
3582        cx: &mut TestAppContext,
3583        editor_mode: EditorMode,
3584        input_text: &str,
3585        editor_width: f32,
3586    ) -> Vec<Invisible> {
3587        info!(
3588            "Creating editor with mode {editor_mode:?}, width {editor_width} and text '{input_text}'"
3589        );
3590        let editor = cx
3591            .add_window(|cx| {
3592                let buffer = MultiBuffer::build_simple(&input_text, cx);
3593                Editor::new(editor_mode, buffer, None, None, cx)
3594            })
3595            .root(cx);
3596
3597        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3598        let (_, layout_state) = editor.update(cx, |editor, cx| {
3599            editor.set_soft_wrap_mode(language_settings::SoftWrap::EditorWidth, cx);
3600            editor.set_wrap_width(Some(editor_width), cx);
3601
3602            let mut new_parents = Default::default();
3603            let mut notify_views_if_parents_change = Default::default();
3604            let mut layout_cx = LayoutContext::new(
3605                cx,
3606                &mut new_parents,
3607                &mut notify_views_if_parents_change,
3608                false,
3609            );
3610            element.layout(
3611                SizeConstraint::new(vec2f(editor_width, 500.), vec2f(editor_width, 500.)),
3612                editor,
3613                &mut layout_cx,
3614            )
3615        });
3616
3617        layout_state
3618            .position_map
3619            .line_layouts
3620            .iter()
3621            .map(|line_with_invisibles| &line_with_invisibles.invisibles)
3622            .flatten()
3623            .cloned()
3624            .collect()
3625    }
3626}