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