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