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