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
1090                    .background_highlights_in_range_for::<crate::items::BufferSearchHighlights>(
1091                        start_anchor..end_anchor,
1092                        &layout.position_map.snapshot,
1093                        &theme,
1094                    )
1095                {
1096                    let start_display = row.start;
1097                    let end_display = row.end;
1098
1099                    if start_row.is_none() {
1100                        assert_eq!(end_row, None);
1101                        start_row = Some(start_display.row());
1102                        end_row = Some(end_display.row());
1103                        continue;
1104                    }
1105                    if let Some(current_end) = end_row.as_mut() {
1106                        if start_display.row() > *current_end + 1 {
1107                            push_region(start_row, end_row);
1108                            start_row = Some(start_display.row());
1109                            end_row = Some(end_display.row());
1110                        } else {
1111                            // Merge two hunks.
1112                            *current_end = end_display.row();
1113                        }
1114                    } else {
1115                        unreachable!();
1116                    }
1117                }
1118                // We might still have a hunk that was not rendered (if there was a search hit on the last line)
1119                push_region(start_row, end_row);
1120            }
1121
1122            if layout.is_singleton && scrollbar_settings.git_diff {
1123                let diff_style = scrollbar_theme.git.clone();
1124                for hunk in layout
1125                    .position_map
1126                    .snapshot
1127                    .buffer_snapshot
1128                    .git_diff_hunks_in_range(0..(max_row.floor() as u32))
1129                {
1130                    let start_display = Point::new(hunk.buffer_range.start, 0)
1131                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1132                    let end_display = Point::new(hunk.buffer_range.end, 0)
1133                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1134                    let start_y = y_for_row(start_display.row() as f32);
1135                    let mut end_y = if hunk.buffer_range.start == hunk.buffer_range.end {
1136                        y_for_row((end_display.row() + 1) as f32)
1137                    } else {
1138                        y_for_row((end_display.row()) as f32)
1139                    };
1140
1141                    if end_y - start_y < 1. {
1142                        end_y = start_y + 1.;
1143                    }
1144                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1145
1146                    let color = match hunk.status() {
1147                        DiffHunkStatus::Added => diff_style.inserted,
1148                        DiffHunkStatus::Modified => diff_style.modified,
1149                        DiffHunkStatus::Removed => diff_style.deleted,
1150                    };
1151
1152                    let border = Border {
1153                        width: 1.,
1154                        color: style.thumb.border.color,
1155                        overlay: false,
1156                        top: false,
1157                        right: true,
1158                        bottom: false,
1159                        left: true,
1160                    };
1161
1162                    scene.push_quad(Quad {
1163                        bounds,
1164                        background: Some(color),
1165                        border,
1166                        corner_radius: style.thumb.corner_radius,
1167                    })
1168                }
1169            }
1170
1171            scene.push_quad(Quad {
1172                bounds: thumb_bounds,
1173                border: style.thumb.border,
1174                background: style.thumb.background_color,
1175                corner_radius: style.thumb.corner_radius,
1176            });
1177        }
1178
1179        scene.push_cursor_region(CursorRegion {
1180            bounds: track_bounds,
1181            style: CursorStyle::Arrow,
1182        });
1183        scene.push_mouse_region(
1184            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1185                .on_move(move |_, editor: &mut Editor, cx| {
1186                    editor.scroll_manager.show_scrollbar(cx);
1187                })
1188                .on_down(MouseButton::Left, {
1189                    let row_range = row_range.clone();
1190                    move |event, editor: &mut Editor, cx| {
1191                        let y = event.position.y();
1192                        if y < thumb_top || thumb_bottom < y {
1193                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1194                            let top_row = center_row
1195                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1196                            let mut position = editor.scroll_position(cx);
1197                            position.set_y(top_row as f32);
1198                            editor.set_scroll_position(position, cx);
1199                        } else {
1200                            editor.scroll_manager.show_scrollbar(cx);
1201                        }
1202                    }
1203                })
1204                .on_drag(MouseButton::Left, {
1205                    move |event, editor: &mut Editor, cx| {
1206                        let y = event.prev_mouse_position.y();
1207                        let new_y = event.position.y();
1208                        if thumb_top < y && y < thumb_bottom {
1209                            let mut position = editor.scroll_position(cx);
1210                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1211                            if position.y() < 0.0 {
1212                                position.set_y(0.);
1213                            }
1214                            editor.set_scroll_position(position, cx);
1215                        }
1216                    }
1217                }),
1218        );
1219    }
1220
1221    #[allow(clippy::too_many_arguments)]
1222    fn paint_highlighted_range(
1223        &self,
1224        scene: &mut SceneBuilder,
1225        range: Range<DisplayPoint>,
1226        color: Color,
1227        corner_radius: f32,
1228        line_end_overshoot: f32,
1229        layout: &LayoutState,
1230        content_origin: Vector2F,
1231        scroll_top: f32,
1232        scroll_left: f32,
1233        bounds: RectF,
1234    ) {
1235        let start_row = layout.visible_display_row_range.start;
1236        let end_row = layout.visible_display_row_range.end;
1237        if range.start != range.end {
1238            let row_range = if range.end.column() == 0 {
1239                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1240            } else {
1241                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1242            };
1243
1244            let highlighted_range = HighlightedRange {
1245                color,
1246                line_height: layout.position_map.line_height,
1247                corner_radius,
1248                start_y: content_origin.y()
1249                    + row_range.start as f32 * layout.position_map.line_height
1250                    - scroll_top,
1251                lines: row_range
1252                    .into_iter()
1253                    .map(|row| {
1254                        let line_layout =
1255                            &layout.position_map.line_layouts[(row - start_row) as usize].line;
1256                        HighlightedRangeLine {
1257                            start_x: if row == range.start.row() {
1258                                content_origin.x()
1259                                    + line_layout.x_for_index(range.start.column() as usize)
1260                                    - scroll_left
1261                            } else {
1262                                content_origin.x() - scroll_left
1263                            },
1264                            end_x: if row == range.end.row() {
1265                                content_origin.x()
1266                                    + line_layout.x_for_index(range.end.column() as usize)
1267                                    - scroll_left
1268                            } else {
1269                                content_origin.x() + line_layout.width() + line_end_overshoot
1270                                    - scroll_left
1271                            },
1272                        }
1273                    })
1274                    .collect(),
1275            };
1276
1277            highlighted_range.paint(bounds, scene);
1278        }
1279    }
1280
1281    fn paint_blocks(
1282        &mut self,
1283        scene: &mut SceneBuilder,
1284        bounds: RectF,
1285        visible_bounds: RectF,
1286        layout: &mut LayoutState,
1287        editor: &mut Editor,
1288        cx: &mut ViewContext<Editor>,
1289    ) {
1290        let scroll_position = layout.position_map.snapshot.scroll_position();
1291        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1292        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1293
1294        for block in &mut layout.blocks {
1295            let mut origin = bounds.origin()
1296                + vec2f(
1297                    0.,
1298                    block.row as f32 * layout.position_map.line_height - scroll_top,
1299                );
1300            if !matches!(block.style, BlockStyle::Sticky) {
1301                origin += vec2f(-scroll_left, 0.);
1302            }
1303            block
1304                .element
1305                .paint(scene, origin, visible_bounds, editor, cx);
1306        }
1307    }
1308
1309    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1310        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1311        let style = &self.style;
1312
1313        cx.text_layout_cache()
1314            .layout_str(
1315                "1".repeat(digit_count).as_str(),
1316                style.text.font_size,
1317                &[(
1318                    digit_count,
1319                    RunStyle {
1320                        font_id: style.text.font_id,
1321                        color: Color::black(),
1322                        underline: Default::default(),
1323                    },
1324                )],
1325            )
1326            .width()
1327    }
1328
1329    //Folds contained in a hunk are ignored apart from shrinking visual size
1330    //If a fold contains any hunks then that fold line is marked as modified
1331    fn layout_git_gutters(
1332        &self,
1333        display_rows: Range<u32>,
1334        snapshot: &EditorSnapshot,
1335    ) -> Vec<DisplayDiffHunk> {
1336        let buffer_snapshot = &snapshot.buffer_snapshot;
1337
1338        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1339            .to_point(snapshot)
1340            .row;
1341        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1342            .to_point(snapshot)
1343            .row;
1344
1345        buffer_snapshot
1346            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row)
1347            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1348            .dedup()
1349            .collect()
1350    }
1351
1352    fn layout_line_numbers(
1353        &self,
1354        rows: Range<u32>,
1355        active_rows: &BTreeMap<u32, bool>,
1356        is_singleton: bool,
1357        snapshot: &EditorSnapshot,
1358        cx: &ViewContext<Editor>,
1359    ) -> (
1360        Vec<Option<text_layout::Line>>,
1361        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1362    ) {
1363        let style = &self.style;
1364        let include_line_numbers = snapshot.mode == EditorMode::Full;
1365        let mut line_number_layouts = Vec::with_capacity(rows.len());
1366        let mut fold_statuses = Vec::with_capacity(rows.len());
1367        let mut line_number = String::new();
1368        for (ix, row) in snapshot
1369            .buffer_rows(rows.start)
1370            .take((rows.end - rows.start) as usize)
1371            .enumerate()
1372        {
1373            let display_row = rows.start + ix as u32;
1374            let (active, color) = if active_rows.contains_key(&display_row) {
1375                (true, style.line_number_active)
1376            } else {
1377                (false, style.line_number)
1378            };
1379            if let Some(buffer_row) = row {
1380                if include_line_numbers {
1381                    line_number.clear();
1382                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1383                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1384                        &line_number,
1385                        style.text.font_size,
1386                        &[(
1387                            line_number.len(),
1388                            RunStyle {
1389                                font_id: style.text.font_id,
1390                                color,
1391                                underline: Default::default(),
1392                            },
1393                        )],
1394                    )));
1395                    fold_statuses.push(
1396                        is_singleton
1397                            .then(|| {
1398                                snapshot
1399                                    .fold_for_line(buffer_row)
1400                                    .map(|fold_status| (fold_status, buffer_row, active))
1401                            })
1402                            .flatten(),
1403                    )
1404                }
1405            } else {
1406                fold_statuses.push(None);
1407                line_number_layouts.push(None);
1408            }
1409        }
1410
1411        (line_number_layouts, fold_statuses)
1412    }
1413
1414    fn layout_lines(
1415        &mut self,
1416        rows: Range<u32>,
1417        line_number_layouts: &[Option<Line>],
1418        snapshot: &EditorSnapshot,
1419        cx: &ViewContext<Editor>,
1420    ) -> Vec<LineWithInvisibles> {
1421        if rows.start >= rows.end {
1422            return Vec::new();
1423        }
1424
1425        // When the editor is empty and unfocused, then show the placeholder.
1426        if snapshot.is_empty() {
1427            let placeholder_style = self
1428                .style
1429                .placeholder_text
1430                .as_ref()
1431                .unwrap_or(&self.style.text);
1432            let placeholder_text = snapshot.placeholder_text();
1433            let placeholder_lines = placeholder_text
1434                .as_ref()
1435                .map_or("", AsRef::as_ref)
1436                .split('\n')
1437                .skip(rows.start as usize)
1438                .chain(iter::repeat(""))
1439                .take(rows.len());
1440            placeholder_lines
1441                .map(|line| {
1442                    cx.text_layout_cache().layout_str(
1443                        line,
1444                        placeholder_style.font_size,
1445                        &[(
1446                            line.len(),
1447                            RunStyle {
1448                                font_id: placeholder_style.font_id,
1449                                color: placeholder_style.color,
1450                                underline: Default::default(),
1451                            },
1452                        )],
1453                    )
1454                })
1455                .map(|line| LineWithInvisibles {
1456                    line,
1457                    invisibles: Vec::new(),
1458                })
1459                .collect()
1460        } else {
1461            let style = &self.style;
1462            let chunks = snapshot
1463                .chunks(
1464                    rows.clone(),
1465                    true,
1466                    Some(style.theme.hint),
1467                    Some(style.theme.suggestion),
1468                )
1469                .map(|chunk| {
1470                    let mut highlight_style = chunk
1471                        .syntax_highlight_id
1472                        .and_then(|id| id.style(&style.syntax));
1473
1474                    if let Some(chunk_highlight) = chunk.highlight_style {
1475                        if let Some(highlight_style) = highlight_style.as_mut() {
1476                            highlight_style.highlight(chunk_highlight);
1477                        } else {
1478                            highlight_style = Some(chunk_highlight);
1479                        }
1480                    }
1481
1482                    let mut diagnostic_highlight = HighlightStyle::default();
1483
1484                    if chunk.is_unnecessary {
1485                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1486                    }
1487
1488                    if let Some(severity) = chunk.diagnostic_severity {
1489                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1490                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1491                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1492                            diagnostic_highlight.underline = Some(Underline {
1493                                color: Some(diagnostic_style.message.text.color),
1494                                thickness: 1.0.into(),
1495                                squiggly: true,
1496                            });
1497                        }
1498                    }
1499
1500                    if let Some(highlight_style) = highlight_style.as_mut() {
1501                        highlight_style.highlight(diagnostic_highlight);
1502                    } else {
1503                        highlight_style = Some(diagnostic_highlight);
1504                    }
1505
1506                    HighlightedChunk {
1507                        chunk: chunk.text,
1508                        style: highlight_style,
1509                        is_tab: chunk.is_tab,
1510                    }
1511                });
1512
1513            LineWithInvisibles::from_chunks(
1514                chunks,
1515                &style.text,
1516                cx.text_layout_cache(),
1517                cx.font_cache(),
1518                MAX_LINE_LEN,
1519                rows.len() as usize,
1520                line_number_layouts,
1521                snapshot.mode,
1522            )
1523        }
1524    }
1525
1526    #[allow(clippy::too_many_arguments)]
1527    fn layout_blocks(
1528        &mut self,
1529        rows: Range<u32>,
1530        snapshot: &EditorSnapshot,
1531        editor_width: f32,
1532        scroll_width: f32,
1533        gutter_padding: f32,
1534        gutter_width: f32,
1535        em_width: f32,
1536        text_x: f32,
1537        line_height: f32,
1538        style: &EditorStyle,
1539        line_layouts: &[LineWithInvisibles],
1540        editor: &mut Editor,
1541        cx: &mut LayoutContext<Editor>,
1542    ) -> (f32, Vec<BlockLayout>) {
1543        let mut block_id = 0;
1544        let scroll_x = snapshot.scroll_anchor.offset.x();
1545        let (fixed_blocks, non_fixed_blocks) = snapshot
1546            .blocks_in_range(rows.clone())
1547            .partition::<Vec<_>, _>(|(_, block)| match block {
1548                TransformBlock::ExcerptHeader { .. } => false,
1549                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1550            });
1551        let mut render_block = |block: &TransformBlock, width: f32, block_id: usize| {
1552            let mut element = match block {
1553                TransformBlock::Custom(block) => {
1554                    let align_to = block
1555                        .position()
1556                        .to_point(&snapshot.buffer_snapshot)
1557                        .to_display_point(snapshot);
1558                    let anchor_x = text_x
1559                        + if rows.contains(&align_to.row()) {
1560                            line_layouts[(align_to.row() - rows.start) as usize]
1561                                .line
1562                                .x_for_index(align_to.column() as usize)
1563                        } else {
1564                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1565                                .x_for_index(align_to.column() as usize)
1566                        };
1567
1568                    block.render(&mut BlockContext {
1569                        view_context: cx,
1570                        anchor_x,
1571                        gutter_padding,
1572                        line_height,
1573                        scroll_x,
1574                        gutter_width,
1575                        em_width,
1576                        block_id,
1577                    })
1578                }
1579                TransformBlock::ExcerptHeader {
1580                    id,
1581                    buffer,
1582                    range,
1583                    starts_new_buffer,
1584                    ..
1585                } => {
1586                    let tooltip_style = theme::current(cx).tooltip.clone();
1587                    let include_root = editor
1588                        .project
1589                        .as_ref()
1590                        .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1591                        .unwrap_or_default();
1592                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1593                        let jump_path = ProjectPath {
1594                            worktree_id: file.worktree_id(cx),
1595                            path: file.path.clone(),
1596                        };
1597                        let jump_anchor = range
1598                            .primary
1599                            .as_ref()
1600                            .map_or(range.context.start, |primary| primary.start);
1601                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1602
1603                        enum JumpIcon {}
1604                        MouseEventHandler::<JumpIcon, _>::new((*id).into(), cx, |state, _| {
1605                            let style = style.jump_icon.style_for(state);
1606                            Svg::new("icons/arrow_up_right_8.svg")
1607                                .with_color(style.color)
1608                                .constrained()
1609                                .with_width(style.icon_width)
1610                                .aligned()
1611                                .contained()
1612                                .with_style(style.container)
1613                                .constrained()
1614                                .with_width(style.button_width)
1615                                .with_height(style.button_width)
1616                        })
1617                        .with_cursor_style(CursorStyle::PointingHand)
1618                        .on_click(MouseButton::Left, move |_, editor, cx| {
1619                            if let Some(workspace) = editor
1620                                .workspace
1621                                .as_ref()
1622                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1623                            {
1624                                workspace.update(cx, |workspace, cx| {
1625                                    Editor::jump(
1626                                        workspace,
1627                                        jump_path.clone(),
1628                                        jump_position,
1629                                        jump_anchor,
1630                                        cx,
1631                                    );
1632                                });
1633                            }
1634                        })
1635                        .with_tooltip::<JumpIcon>(
1636                            (*id).into(),
1637                            "Jump to Buffer".to_string(),
1638                            Some(Box::new(crate::OpenExcerpts)),
1639                            tooltip_style.clone(),
1640                            cx,
1641                        )
1642                        .aligned()
1643                        .flex_float()
1644                    });
1645
1646                    if *starts_new_buffer {
1647                        let editor_font_size = style.text.font_size;
1648                        let style = &style.diagnostic_path_header;
1649                        let font_size = (style.text_scale_factor * editor_font_size).round();
1650
1651                        let path = buffer.resolve_file_path(cx, include_root);
1652                        let mut filename = None;
1653                        let mut parent_path = None;
1654                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1655                        if let Some(path) = path {
1656                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1657                            parent_path =
1658                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1659                        }
1660
1661                        Flex::row()
1662                            .with_child(
1663                                Label::new(
1664                                    filename.unwrap_or_else(|| "untitled".to_string()),
1665                                    style.filename.text.clone().with_font_size(font_size),
1666                                )
1667                                .contained()
1668                                .with_style(style.filename.container)
1669                                .aligned(),
1670                            )
1671                            .with_children(parent_path.map(|path| {
1672                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1673                                    .contained()
1674                                    .with_style(style.path.container)
1675                                    .aligned()
1676                            }))
1677                            .with_children(jump_icon)
1678                            .contained()
1679                            .with_style(style.container)
1680                            .with_padding_left(gutter_padding)
1681                            .with_padding_right(gutter_padding)
1682                            .expanded()
1683                            .into_any_named("path header block")
1684                    } else {
1685                        let text_style = style.text.clone();
1686                        Flex::row()
1687                            .with_child(Label::new("", text_style))
1688                            .with_children(jump_icon)
1689                            .contained()
1690                            .with_padding_left(gutter_padding)
1691                            .with_padding_right(gutter_padding)
1692                            .expanded()
1693                            .into_any_named("collapsed context")
1694                    }
1695                }
1696            };
1697
1698            element.layout(
1699                SizeConstraint {
1700                    min: Vector2F::zero(),
1701                    max: vec2f(width, block.height() as f32 * line_height),
1702                },
1703                editor,
1704                cx,
1705            );
1706            element
1707        };
1708
1709        let mut fixed_block_max_width = 0f32;
1710        let mut blocks = Vec::new();
1711        for (row, block) in fixed_blocks {
1712            let element = render_block(block, f32::INFINITY, block_id);
1713            block_id += 1;
1714            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1715            blocks.push(BlockLayout {
1716                row,
1717                element,
1718                style: BlockStyle::Fixed,
1719            });
1720        }
1721        for (row, block) in non_fixed_blocks {
1722            let style = match block {
1723                TransformBlock::Custom(block) => block.style(),
1724                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1725            };
1726            let width = match style {
1727                BlockStyle::Sticky => editor_width,
1728                BlockStyle::Flex => editor_width
1729                    .max(fixed_block_max_width)
1730                    .max(gutter_width + scroll_width),
1731                BlockStyle::Fixed => unreachable!(),
1732            };
1733            let element = render_block(block, width, block_id);
1734            block_id += 1;
1735            blocks.push(BlockLayout {
1736                row,
1737                element,
1738                style,
1739            });
1740        }
1741        (
1742            scroll_width.max(fixed_block_max_width - gutter_width),
1743            blocks,
1744        )
1745    }
1746}
1747
1748struct HighlightedChunk<'a> {
1749    chunk: &'a str,
1750    style: Option<HighlightStyle>,
1751    is_tab: bool,
1752}
1753
1754#[derive(Debug)]
1755pub struct LineWithInvisibles {
1756    pub line: Line,
1757    invisibles: Vec<Invisible>,
1758}
1759
1760impl LineWithInvisibles {
1761    fn from_chunks<'a>(
1762        chunks: impl Iterator<Item = HighlightedChunk<'a>>,
1763        text_style: &TextStyle,
1764        text_layout_cache: &TextLayoutCache,
1765        font_cache: &Arc<FontCache>,
1766        max_line_len: usize,
1767        max_line_count: usize,
1768        line_number_layouts: &[Option<Line>],
1769        editor_mode: EditorMode,
1770    ) -> Vec<Self> {
1771        let mut layouts = Vec::with_capacity(max_line_count);
1772        let mut line = String::new();
1773        let mut invisibles = Vec::new();
1774        let mut styles = Vec::new();
1775        let mut non_whitespace_added = false;
1776        let mut row = 0;
1777        let mut line_exceeded_max_len = false;
1778        for highlighted_chunk in chunks.chain([HighlightedChunk {
1779            chunk: "\n",
1780            style: None,
1781            is_tab: false,
1782        }]) {
1783            for (ix, mut line_chunk) in highlighted_chunk.chunk.split('\n').enumerate() {
1784                if ix > 0 {
1785                    layouts.push(Self {
1786                        line: text_layout_cache.layout_str(&line, text_style.font_size, &styles),
1787                        invisibles: invisibles.drain(..).collect(),
1788                    });
1789
1790                    line.clear();
1791                    styles.clear();
1792                    row += 1;
1793                    line_exceeded_max_len = false;
1794                    non_whitespace_added = false;
1795                    if row == max_line_count {
1796                        return layouts;
1797                    }
1798                }
1799
1800                if !line_chunk.is_empty() && !line_exceeded_max_len {
1801                    let text_style = if let Some(style) = highlighted_chunk.style {
1802                        text_style
1803                            .clone()
1804                            .highlight(style, font_cache)
1805                            .map(Cow::Owned)
1806                            .unwrap_or_else(|_| Cow::Borrowed(text_style))
1807                    } else {
1808                        Cow::Borrowed(text_style)
1809                    };
1810
1811                    if line.len() + line_chunk.len() > max_line_len {
1812                        let mut chunk_len = max_line_len - line.len();
1813                        while !line_chunk.is_char_boundary(chunk_len) {
1814                            chunk_len -= 1;
1815                        }
1816                        line_chunk = &line_chunk[..chunk_len];
1817                        line_exceeded_max_len = true;
1818                    }
1819
1820                    styles.push((
1821                        line_chunk.len(),
1822                        RunStyle {
1823                            font_id: text_style.font_id,
1824                            color: text_style.color,
1825                            underline: text_style.underline,
1826                        },
1827                    ));
1828
1829                    if editor_mode == EditorMode::Full {
1830                        // Line wrap pads its contents with fake whitespaces,
1831                        // avoid printing them
1832                        let inside_wrapped_string = line_number_layouts
1833                            .get(row)
1834                            .and_then(|layout| layout.as_ref())
1835                            .is_none();
1836                        if highlighted_chunk.is_tab {
1837                            if non_whitespace_added || !inside_wrapped_string {
1838                                invisibles.push(Invisible::Tab {
1839                                    line_start_offset: line.len(),
1840                                });
1841                            }
1842                        } else {
1843                            invisibles.extend(
1844                                line_chunk
1845                                    .chars()
1846                                    .enumerate()
1847                                    .filter(|(_, line_char)| {
1848                                        let is_whitespace = line_char.is_whitespace();
1849                                        non_whitespace_added |= !is_whitespace;
1850                                        is_whitespace
1851                                            && (non_whitespace_added || !inside_wrapped_string)
1852                                    })
1853                                    .map(|(whitespace_index, _)| Invisible::Whitespace {
1854                                        line_offset: line.len() + whitespace_index,
1855                                    }),
1856                            )
1857                        }
1858                    }
1859
1860                    line.push_str(line_chunk);
1861                }
1862            }
1863        }
1864
1865        layouts
1866    }
1867
1868    fn draw(
1869        &self,
1870        layout: &LayoutState,
1871        row: u32,
1872        scroll_top: f32,
1873        scene: &mut SceneBuilder,
1874        content_origin: Vector2F,
1875        scroll_left: f32,
1876        visible_text_bounds: RectF,
1877        whitespace_setting: ShowWhitespaceSetting,
1878        selection_ranges: &[Range<DisplayPoint>],
1879        visible_bounds: RectF,
1880        cx: &mut ViewContext<Editor>,
1881    ) {
1882        let line_height = layout.position_map.line_height;
1883        let line_y = row as f32 * line_height - scroll_top;
1884
1885        self.line.paint(
1886            scene,
1887            content_origin + vec2f(-scroll_left, line_y),
1888            visible_text_bounds,
1889            line_height,
1890            cx,
1891        );
1892
1893        self.draw_invisibles(
1894            &selection_ranges,
1895            layout,
1896            content_origin,
1897            scroll_left,
1898            line_y,
1899            row,
1900            scene,
1901            visible_bounds,
1902            line_height,
1903            whitespace_setting,
1904            cx,
1905        );
1906    }
1907
1908    fn draw_invisibles(
1909        &self,
1910        selection_ranges: &[Range<DisplayPoint>],
1911        layout: &LayoutState,
1912        content_origin: Vector2F,
1913        scroll_left: f32,
1914        line_y: f32,
1915        row: u32,
1916        scene: &mut SceneBuilder,
1917        visible_bounds: RectF,
1918        line_height: f32,
1919        whitespace_setting: ShowWhitespaceSetting,
1920        cx: &mut ViewContext<Editor>,
1921    ) {
1922        let allowed_invisibles_regions = match whitespace_setting {
1923            ShowWhitespaceSetting::None => return,
1924            ShowWhitespaceSetting::Selection => Some(selection_ranges),
1925            ShowWhitespaceSetting::All => None,
1926        };
1927
1928        for invisible in &self.invisibles {
1929            let (&token_offset, invisible_symbol) = match invisible {
1930                Invisible::Tab { line_start_offset } => (line_start_offset, &layout.tab_invisible),
1931                Invisible::Whitespace { line_offset } => (line_offset, &layout.space_invisible),
1932            };
1933
1934            let x_offset = self.line.x_for_index(token_offset);
1935            let invisible_offset =
1936                (layout.position_map.em_width - invisible_symbol.width()).max(0.0) / 2.0;
1937            let origin = content_origin + vec2f(-scroll_left + x_offset + invisible_offset, line_y);
1938
1939            if let Some(allowed_regions) = allowed_invisibles_regions {
1940                let invisible_point = DisplayPoint::new(row, token_offset as u32);
1941                if !allowed_regions
1942                    .iter()
1943                    .any(|region| region.start <= invisible_point && invisible_point < region.end)
1944                {
1945                    continue;
1946                }
1947            }
1948            invisible_symbol.paint(scene, origin, visible_bounds, line_height, cx);
1949        }
1950    }
1951}
1952
1953#[derive(Debug, Clone, Copy, PartialEq, Eq)]
1954enum Invisible {
1955    Tab { line_start_offset: usize },
1956    Whitespace { line_offset: usize },
1957}
1958
1959impl Element<Editor> for EditorElement {
1960    type LayoutState = LayoutState;
1961    type PaintState = ();
1962
1963    fn layout(
1964        &mut self,
1965        constraint: SizeConstraint,
1966        editor: &mut Editor,
1967        cx: &mut LayoutContext<Editor>,
1968    ) -> (Vector2F, Self::LayoutState) {
1969        let mut size = constraint.max;
1970        if size.x().is_infinite() {
1971            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1972        }
1973
1974        let snapshot = editor.snapshot(cx);
1975        let style = self.style.clone();
1976        let line_height = style.text.line_height(cx.font_cache());
1977
1978        let gutter_padding;
1979        let gutter_width;
1980        let gutter_margin;
1981        if snapshot.show_gutter {
1982            let em_width = style.text.em_width(cx.font_cache());
1983            gutter_padding = (em_width * style.gutter_padding_factor).round();
1984            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1985            gutter_margin = -style.text.descent(cx.font_cache());
1986        } else {
1987            gutter_padding = 0.0;
1988            gutter_width = 0.0;
1989            gutter_margin = 0.0;
1990        };
1991
1992        let text_width = size.x() - gutter_width;
1993        let em_width = style.text.em_width(cx.font_cache());
1994        let em_advance = style.text.em_advance(cx.font_cache());
1995        let overscroll = vec2f(em_width, 0.);
1996        let snapshot = {
1997            editor.set_visible_line_count(size.y() / line_height, cx);
1998
1999            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
2000            let wrap_width = match editor.soft_wrap_mode(cx) {
2001                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
2002                SoftWrap::EditorWidth => editor_width,
2003                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
2004            };
2005
2006            if editor.set_wrap_width(Some(wrap_width), cx) {
2007                editor.snapshot(cx)
2008            } else {
2009                snapshot
2010            }
2011        };
2012
2013        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
2014        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
2015            size.set_y(
2016                scroll_height
2017                    .min(constraint.max_along(Axis::Vertical))
2018                    .max(constraint.min_along(Axis::Vertical))
2019                    .min(line_height * max_lines as f32),
2020            )
2021        } else if let EditorMode::SingleLine = snapshot.mode {
2022            size.set_y(
2023                line_height
2024                    .min(constraint.max_along(Axis::Vertical))
2025                    .max(constraint.min_along(Axis::Vertical)),
2026            )
2027        } else if size.y().is_infinite() {
2028            size.set_y(scroll_height);
2029        }
2030        let gutter_size = vec2f(gutter_width, size.y());
2031        let text_size = vec2f(text_width, size.y());
2032
2033        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
2034        let mut snapshot = editor.snapshot(cx);
2035
2036        let scroll_position = snapshot.scroll_position();
2037        // The scroll position is a fractional point, the whole number of which represents
2038        // the top of the window in terms of display rows.
2039        let start_row = scroll_position.y() as u32;
2040        let height_in_lines = size.y() / line_height;
2041        let max_row = snapshot.max_point().row();
2042
2043        // Add 1 to ensure selections bleed off screen
2044        let end_row = 1 + cmp::min(
2045            (scroll_position.y() + height_in_lines).ceil() as u32,
2046            max_row,
2047        );
2048
2049        let start_anchor = if start_row == 0 {
2050            Anchor::min()
2051        } else {
2052            snapshot
2053                .buffer_snapshot
2054                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
2055        };
2056        let end_anchor = if end_row > max_row {
2057            Anchor::max()
2058        } else {
2059            snapshot
2060                .buffer_snapshot
2061                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
2062        };
2063
2064        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
2065        let mut active_rows = BTreeMap::new();
2066        let mut fold_ranges = Vec::new();
2067        let is_singleton = editor.is_singleton(cx);
2068
2069        let highlighted_rows = editor.highlighted_rows();
2070        let theme = theme::current(cx);
2071        let highlighted_ranges = editor.background_highlights_in_range(
2072            start_anchor..end_anchor,
2073            &snapshot.display_snapshot,
2074            theme.as_ref(),
2075        );
2076
2077        fold_ranges.extend(
2078            snapshot
2079                .folds_in_range(start_anchor..end_anchor)
2080                .map(|anchor| {
2081                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
2082                    (
2083                        start.row,
2084                        start.to_display_point(&snapshot.display_snapshot)
2085                            ..anchor.end.to_display_point(&snapshot),
2086                    )
2087                }),
2088        );
2089
2090        let mut remote_selections = HashMap::default();
2091        for (replica_id, line_mode, cursor_shape, selection) in snapshot
2092            .buffer_snapshot
2093            .remote_selections_in_range(&(start_anchor..end_anchor))
2094        {
2095            // The local selections match the leader's selections.
2096            if Some(replica_id) == editor.leader_replica_id {
2097                continue;
2098            }
2099            remote_selections
2100                .entry(replica_id)
2101                .or_insert(Vec::new())
2102                .push(SelectionLayout::new(
2103                    selection,
2104                    line_mode,
2105                    cursor_shape,
2106                    &snapshot.display_snapshot,
2107                ));
2108        }
2109        selections.extend(remote_selections);
2110
2111        if editor.show_local_selections {
2112            let mut local_selections = editor
2113                .selections
2114                .disjoint_in_range(start_anchor..end_anchor, cx);
2115            local_selections.extend(editor.selections.pending(cx));
2116            for selection in &local_selections {
2117                let is_empty = selection.start == selection.end;
2118                let selection_start = snapshot.prev_line_boundary(selection.start).1;
2119                let selection_end = snapshot.next_line_boundary(selection.end).1;
2120                for row in cmp::max(selection_start.row(), start_row)
2121                    ..=cmp::min(selection_end.row(), end_row)
2122                {
2123                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
2124                    *contains_non_empty_selection |= !is_empty;
2125                }
2126            }
2127
2128            // Render the local selections in the leader's color when following.
2129            let local_replica_id = editor
2130                .leader_replica_id
2131                .unwrap_or_else(|| editor.replica_id(cx));
2132
2133            selections.push((
2134                local_replica_id,
2135                local_selections
2136                    .into_iter()
2137                    .map(|selection| {
2138                        SelectionLayout::new(
2139                            selection,
2140                            editor.selections.line_mode,
2141                            editor.cursor_shape,
2142                            &snapshot.display_snapshot,
2143                        )
2144                    })
2145                    .collect(),
2146            ));
2147        }
2148
2149        let scrollbar_settings = &settings::get::<EditorSettings>(cx).scrollbar;
2150        let show_scrollbars = match scrollbar_settings.show {
2151            ShowScrollbar::Auto => {
2152                // Git
2153                (is_singleton && scrollbar_settings.git_diff && snapshot.buffer_snapshot.has_git_diffs())
2154                ||
2155                // Selections
2156                (is_singleton && scrollbar_settings.selections && !highlighted_ranges.is_empty())
2157                // Scrollmanager
2158                || editor.scroll_manager.scrollbars_visible()
2159            }
2160            ShowScrollbar::System => editor.scroll_manager.scrollbars_visible(),
2161            ShowScrollbar::Always => true,
2162            ShowScrollbar::Never => false,
2163        };
2164
2165        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
2166            .into_iter()
2167            .map(|(id, fold)| {
2168                let color = self
2169                    .style
2170                    .folds
2171                    .ellipses
2172                    .background
2173                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize))
2174                    .color;
2175
2176                (id, fold, color)
2177            })
2178            .collect();
2179
2180        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
2181            start_row..end_row,
2182            &active_rows,
2183            is_singleton,
2184            &snapshot,
2185            cx,
2186        );
2187
2188        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
2189
2190        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
2191
2192        let mut max_visible_line_width = 0.0;
2193        let line_layouts =
2194            self.layout_lines(start_row..end_row, &line_number_layouts, &snapshot, cx);
2195        for line_with_invisibles in &line_layouts {
2196            if line_with_invisibles.line.width() > max_visible_line_width {
2197                max_visible_line_width = line_with_invisibles.line.width();
2198            }
2199        }
2200
2201        let style = self.style.clone();
2202        let longest_line_width = layout_line(
2203            snapshot.longest_row(),
2204            &snapshot,
2205            &style,
2206            cx.text_layout_cache(),
2207        )
2208        .width();
2209        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
2210        let em_width = style.text.em_width(cx.font_cache());
2211        let (scroll_width, blocks) = self.layout_blocks(
2212            start_row..end_row,
2213            &snapshot,
2214            size.x(),
2215            scroll_width,
2216            gutter_padding,
2217            gutter_width,
2218            em_width,
2219            gutter_width + gutter_margin,
2220            line_height,
2221            &style,
2222            &line_layouts,
2223            editor,
2224            cx,
2225        );
2226
2227        let scroll_max = vec2f(
2228            ((scroll_width - text_size.x()) / em_width).max(0.0),
2229            max_row as f32,
2230        );
2231
2232        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
2233
2234        let autoscrolled = if autoscroll_horizontally {
2235            editor.autoscroll_horizontally(
2236                start_row,
2237                text_size.x(),
2238                scroll_width,
2239                em_width,
2240                &line_layouts,
2241                cx,
2242            )
2243        } else {
2244            false
2245        };
2246
2247        if clamped || autoscrolled {
2248            snapshot = editor.snapshot(cx);
2249        }
2250
2251        let newest_selection_head = editor
2252            .selections
2253            .newest::<usize>(cx)
2254            .head()
2255            .to_display_point(&snapshot);
2256        let style = editor.style(cx);
2257
2258        let mut context_menu = None;
2259        let mut code_actions_indicator = None;
2260        if (start_row..end_row).contains(&newest_selection_head.row()) {
2261            if editor.context_menu_visible() {
2262                context_menu = editor.render_context_menu(newest_selection_head, style.clone(), cx);
2263            }
2264
2265            let active = matches!(
2266                editor.context_menu,
2267                Some(crate::ContextMenu::CodeActions(_))
2268            );
2269
2270            code_actions_indicator = editor
2271                .render_code_actions_indicator(&style, active, cx)
2272                .map(|indicator| (newest_selection_head.row(), indicator));
2273        }
2274
2275        let visible_rows = start_row..start_row + line_layouts.len() as u32;
2276        let mut hover = editor
2277            .hover_state
2278            .render(&snapshot, &style, visible_rows, cx);
2279        let mode = editor.mode;
2280
2281        let mut fold_indicators = editor.render_fold_indicators(
2282            fold_statuses,
2283            &style,
2284            editor.gutter_hovered,
2285            line_height,
2286            gutter_margin,
2287            cx,
2288        );
2289
2290        if let Some((_, context_menu)) = context_menu.as_mut() {
2291            context_menu.layout(
2292                SizeConstraint {
2293                    min: Vector2F::zero(),
2294                    max: vec2f(
2295                        cx.window_size().x() * 0.7,
2296                        (12. * line_height).min((size.y() - line_height) / 2.),
2297                    ),
2298                },
2299                editor,
2300                cx,
2301            );
2302        }
2303
2304        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
2305            indicator.layout(
2306                SizeConstraint::strict_along(
2307                    Axis::Vertical,
2308                    line_height * style.code_actions.vertical_scale,
2309                ),
2310                editor,
2311                cx,
2312            );
2313        }
2314
2315        for fold_indicator in fold_indicators.iter_mut() {
2316            if let Some(indicator) = fold_indicator.as_mut() {
2317                indicator.layout(
2318                    SizeConstraint::strict_along(
2319                        Axis::Vertical,
2320                        line_height * style.code_actions.vertical_scale,
2321                    ),
2322                    editor,
2323                    cx,
2324                );
2325            }
2326        }
2327
2328        if let Some((_, hover_popovers)) = hover.as_mut() {
2329            for hover_popover in hover_popovers.iter_mut() {
2330                hover_popover.layout(
2331                    SizeConstraint {
2332                        min: Vector2F::zero(),
2333                        max: vec2f(
2334                            (120. * em_width) // Default size
2335                                .min(size.x() / 2.) // Shrink to half of the editor width
2336                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
2337                            (16. * line_height) // Default size
2338                                .min(size.y() / 2.) // Shrink to half of the editor height
2339                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
2340                        ),
2341                    },
2342                    editor,
2343                    cx,
2344                );
2345            }
2346        }
2347
2348        let invisible_symbol_font_size = self.style.text.font_size / 2.0;
2349        let invisible_symbol_style = RunStyle {
2350            color: self.style.whitespace,
2351            font_id: self.style.text.font_id,
2352            underline: Default::default(),
2353        };
2354
2355        (
2356            size,
2357            LayoutState {
2358                mode,
2359                position_map: Arc::new(PositionMap {
2360                    size,
2361                    scroll_max,
2362                    line_layouts,
2363                    line_height,
2364                    em_width,
2365                    em_advance,
2366                    snapshot,
2367                }),
2368                visible_display_row_range: start_row..end_row,
2369                gutter_size,
2370                gutter_padding,
2371                text_size,
2372                scrollbar_row_range,
2373                show_scrollbars,
2374                is_singleton,
2375                max_row,
2376                gutter_margin,
2377                active_rows,
2378                highlighted_rows,
2379                highlighted_ranges,
2380                fold_ranges,
2381                line_number_layouts,
2382                display_hunks,
2383                blocks,
2384                selections,
2385                context_menu,
2386                code_actions_indicator,
2387                fold_indicators,
2388                tab_invisible: cx.text_layout_cache().layout_str(
2389                    "",
2390                    invisible_symbol_font_size,
2391                    &[("".len(), invisible_symbol_style)],
2392                ),
2393                space_invisible: cx.text_layout_cache().layout_str(
2394                    "",
2395                    invisible_symbol_font_size,
2396                    &[("".len(), invisible_symbol_style)],
2397                ),
2398                hover_popovers: hover,
2399            },
2400        )
2401    }
2402
2403    fn paint(
2404        &mut self,
2405        scene: &mut SceneBuilder,
2406        bounds: RectF,
2407        visible_bounds: RectF,
2408        layout: &mut Self::LayoutState,
2409        editor: &mut Editor,
2410        cx: &mut ViewContext<Editor>,
2411    ) -> Self::PaintState {
2412        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2413        scene.push_layer(Some(visible_bounds));
2414
2415        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2416        let text_bounds = RectF::new(
2417            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2418            layout.text_size,
2419        );
2420
2421        Self::attach_mouse_handlers(
2422            scene,
2423            &layout.position_map,
2424            layout.hover_popovers.is_some(),
2425            visible_bounds,
2426            text_bounds,
2427            gutter_bounds,
2428            bounds,
2429            cx,
2430        );
2431
2432        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2433        if layout.gutter_size.x() > 0. {
2434            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2435        }
2436        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2437
2438        scene.push_layer(Some(bounds));
2439        if !layout.blocks.is_empty() {
2440            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2441        }
2442        self.paint_scrollbar(scene, bounds, layout, cx, &editor);
2443        scene.pop_layer();
2444
2445        scene.pop_layer();
2446    }
2447
2448    fn rect_for_text_range(
2449        &self,
2450        range_utf16: Range<usize>,
2451        bounds: RectF,
2452        _: RectF,
2453        layout: &Self::LayoutState,
2454        _: &Self::PaintState,
2455        _: &Editor,
2456        _: &ViewContext<Editor>,
2457    ) -> Option<RectF> {
2458        let text_bounds = RectF::new(
2459            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2460            layout.text_size,
2461        );
2462        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2463        let scroll_position = layout.position_map.snapshot.scroll_position();
2464        let start_row = scroll_position.y() as u32;
2465        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2466        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2467
2468        let range_start = OffsetUtf16(range_utf16.start)
2469            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2470        if range_start.row() < start_row {
2471            return None;
2472        }
2473
2474        let line = &layout
2475            .position_map
2476            .line_layouts
2477            .get((range_start.row() - start_row) as usize)?
2478            .line;
2479        let range_start_x = line.x_for_index(range_start.column() as usize);
2480        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2481        Some(RectF::new(
2482            content_origin
2483                + vec2f(
2484                    range_start_x,
2485                    range_start_y + layout.position_map.line_height,
2486                )
2487                - vec2f(scroll_left, scroll_top),
2488            vec2f(
2489                layout.position_map.em_width,
2490                layout.position_map.line_height,
2491            ),
2492        ))
2493    }
2494
2495    fn debug(
2496        &self,
2497        bounds: RectF,
2498        _: &Self::LayoutState,
2499        _: &Self::PaintState,
2500        _: &Editor,
2501        _: &ViewContext<Editor>,
2502    ) -> json::Value {
2503        json!({
2504            "type": "BufferElement",
2505            "bounds": bounds.to_json()
2506        })
2507    }
2508}
2509
2510type BufferRow = u32;
2511
2512pub struct LayoutState {
2513    position_map: Arc<PositionMap>,
2514    gutter_size: Vector2F,
2515    gutter_padding: f32,
2516    gutter_margin: f32,
2517    text_size: Vector2F,
2518    mode: EditorMode,
2519    visible_display_row_range: Range<u32>,
2520    active_rows: BTreeMap<u32, bool>,
2521    highlighted_rows: Option<Range<u32>>,
2522    line_number_layouts: Vec<Option<text_layout::Line>>,
2523    display_hunks: Vec<DisplayDiffHunk>,
2524    blocks: Vec<BlockLayout>,
2525    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2526    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2527    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2528    scrollbar_row_range: Range<f32>,
2529    show_scrollbars: bool,
2530    is_singleton: bool,
2531    max_row: u32,
2532    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2533    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2534    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2535    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2536    tab_invisible: Line,
2537    space_invisible: Line,
2538}
2539
2540struct PositionMap {
2541    size: Vector2F,
2542    line_height: f32,
2543    scroll_max: Vector2F,
2544    em_width: f32,
2545    em_advance: f32,
2546    line_layouts: Vec<LineWithInvisibles>,
2547    snapshot: EditorSnapshot,
2548}
2549
2550impl PositionMap {
2551    /// Returns two display points:
2552    /// 1. The nearest *valid* position in the editor
2553    /// 2. An unclipped, potentially *invalid* position that maps directly to
2554    ///    the given pixel position.
2555    fn point_for_position(
2556        &self,
2557        text_bounds: RectF,
2558        position: Vector2F,
2559    ) -> (DisplayPoint, DisplayPoint) {
2560        let scroll_position = self.snapshot.scroll_position();
2561        let position = position - text_bounds.origin();
2562        let y = position.y().max(0.0).min(self.size.y());
2563        let x = position.x() + (scroll_position.x() * self.em_width);
2564        let row = (y / self.line_height + scroll_position.y()) as u32;
2565        let (column, x_overshoot) = if let Some(line) = self
2566            .line_layouts
2567            .get(row as usize - scroll_position.y() as usize)
2568            .map(|line_with_spaces| &line_with_spaces.line)
2569        {
2570            if let Some(ix) = line.index_for_x(x) {
2571                (ix as u32, 0.0)
2572            } else {
2573                (line.len() as u32, 0f32.max(x - line.width()))
2574            }
2575        } else {
2576            (0, x)
2577        };
2578
2579        let mut target_point = DisplayPoint::new(row, column);
2580        let point = self.snapshot.clip_point(target_point, Bias::Left);
2581        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2582
2583        (point, target_point)
2584    }
2585}
2586
2587struct BlockLayout {
2588    row: u32,
2589    element: AnyElement<Editor>,
2590    style: BlockStyle,
2591}
2592
2593fn layout_line(
2594    row: u32,
2595    snapshot: &EditorSnapshot,
2596    style: &EditorStyle,
2597    layout_cache: &TextLayoutCache,
2598) -> text_layout::Line {
2599    let mut line = snapshot.line(row);
2600
2601    if line.len() > MAX_LINE_LEN {
2602        let mut len = MAX_LINE_LEN;
2603        while !line.is_char_boundary(len) {
2604            len -= 1;
2605        }
2606
2607        line.truncate(len);
2608    }
2609
2610    layout_cache.layout_str(
2611        &line,
2612        style.text.font_size,
2613        &[(
2614            snapshot.line_len(row) as usize,
2615            RunStyle {
2616                font_id: style.text.font_id,
2617                color: Color::black(),
2618                underline: Default::default(),
2619            },
2620        )],
2621    )
2622}
2623
2624#[derive(Debug)]
2625pub struct Cursor {
2626    origin: Vector2F,
2627    block_width: f32,
2628    line_height: f32,
2629    color: Color,
2630    shape: CursorShape,
2631    block_text: Option<Line>,
2632}
2633
2634impl Cursor {
2635    pub fn new(
2636        origin: Vector2F,
2637        block_width: f32,
2638        line_height: f32,
2639        color: Color,
2640        shape: CursorShape,
2641        block_text: Option<Line>,
2642    ) -> Cursor {
2643        Cursor {
2644            origin,
2645            block_width,
2646            line_height,
2647            color,
2648            shape,
2649            block_text,
2650        }
2651    }
2652
2653    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2654        RectF::new(
2655            self.origin + origin,
2656            vec2f(self.block_width, self.line_height),
2657        )
2658    }
2659
2660    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2661        let bounds = match self.shape {
2662            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2663            CursorShape::Block | CursorShape::Hollow => RectF::new(
2664                self.origin + origin,
2665                vec2f(self.block_width, self.line_height),
2666            ),
2667            CursorShape::Underscore => RectF::new(
2668                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2669                vec2f(self.block_width, 2.0),
2670            ),
2671        };
2672
2673        //Draw background or border quad
2674        if matches!(self.shape, CursorShape::Hollow) {
2675            scene.push_quad(Quad {
2676                bounds,
2677                background: None,
2678                border: Border::all(1., self.color),
2679                corner_radius: 0.,
2680            });
2681        } else {
2682            scene.push_quad(Quad {
2683                bounds,
2684                background: Some(self.color),
2685                border: Default::default(),
2686                corner_radius: 0.,
2687            });
2688        }
2689
2690        if let Some(block_text) = &self.block_text {
2691            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2692        }
2693    }
2694
2695    pub fn shape(&self) -> CursorShape {
2696        self.shape
2697    }
2698}
2699
2700#[derive(Debug)]
2701pub struct HighlightedRange {
2702    pub start_y: f32,
2703    pub line_height: f32,
2704    pub lines: Vec<HighlightedRangeLine>,
2705    pub color: Color,
2706    pub corner_radius: f32,
2707}
2708
2709#[derive(Debug)]
2710pub struct HighlightedRangeLine {
2711    pub start_x: f32,
2712    pub end_x: f32,
2713}
2714
2715impl HighlightedRange {
2716    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2717        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2718            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2719            self.paint_lines(
2720                self.start_y + self.line_height,
2721                &self.lines[1..],
2722                bounds,
2723                scene,
2724            );
2725        } else {
2726            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2727        }
2728    }
2729
2730    fn paint_lines(
2731        &self,
2732        start_y: f32,
2733        lines: &[HighlightedRangeLine],
2734        bounds: RectF,
2735        scene: &mut SceneBuilder,
2736    ) {
2737        if lines.is_empty() {
2738            return;
2739        }
2740
2741        let mut path = PathBuilder::new();
2742        let first_line = lines.first().unwrap();
2743        let last_line = lines.last().unwrap();
2744
2745        let first_top_left = vec2f(first_line.start_x, start_y);
2746        let first_top_right = vec2f(first_line.end_x, start_y);
2747
2748        let curve_height = vec2f(0., self.corner_radius);
2749        let curve_width = |start_x: f32, end_x: f32| {
2750            let max = (end_x - start_x) / 2.;
2751            let width = if max < self.corner_radius {
2752                max
2753            } else {
2754                self.corner_radius
2755            };
2756
2757            vec2f(width, 0.)
2758        };
2759
2760        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2761        path.reset(first_top_right - top_curve_width);
2762        path.curve_to(first_top_right + curve_height, first_top_right);
2763
2764        let mut iter = lines.iter().enumerate().peekable();
2765        while let Some((ix, line)) = iter.next() {
2766            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2767
2768            if let Some((_, next_line)) = iter.peek() {
2769                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2770
2771                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2772                    Ordering::Equal => {
2773                        path.line_to(bottom_right);
2774                    }
2775                    Ordering::Less => {
2776                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2777                        path.line_to(bottom_right - curve_height);
2778                        if self.corner_radius > 0. {
2779                            path.curve_to(bottom_right - curve_width, bottom_right);
2780                        }
2781                        path.line_to(next_top_right + curve_width);
2782                        if self.corner_radius > 0. {
2783                            path.curve_to(next_top_right + curve_height, next_top_right);
2784                        }
2785                    }
2786                    Ordering::Greater => {
2787                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2788                        path.line_to(bottom_right - curve_height);
2789                        if self.corner_radius > 0. {
2790                            path.curve_to(bottom_right + curve_width, bottom_right);
2791                        }
2792                        path.line_to(next_top_right - curve_width);
2793                        if self.corner_radius > 0. {
2794                            path.curve_to(next_top_right + curve_height, next_top_right);
2795                        }
2796                    }
2797                }
2798            } else {
2799                let curve_width = curve_width(line.start_x, line.end_x);
2800                path.line_to(bottom_right - curve_height);
2801                if self.corner_radius > 0. {
2802                    path.curve_to(bottom_right - curve_width, bottom_right);
2803                }
2804
2805                let bottom_left = vec2f(line.start_x, bottom_right.y());
2806                path.line_to(bottom_left + curve_width);
2807                if self.corner_radius > 0. {
2808                    path.curve_to(bottom_left - curve_height, bottom_left);
2809                }
2810            }
2811        }
2812
2813        if first_line.start_x > last_line.start_x {
2814            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2815            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2816            path.line_to(second_top_left + curve_height);
2817            if self.corner_radius > 0. {
2818                path.curve_to(second_top_left + curve_width, second_top_left);
2819            }
2820            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2821            path.line_to(first_bottom_left - curve_width);
2822            if self.corner_radius > 0. {
2823                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2824            }
2825        }
2826
2827        path.line_to(first_top_left + curve_height);
2828        if self.corner_radius > 0. {
2829            path.curve_to(first_top_left + top_curve_width, first_top_left);
2830        }
2831        path.line_to(first_top_right - top_curve_width);
2832
2833        scene.push_path(path.build(self.color, Some(bounds)));
2834    }
2835}
2836
2837fn position_to_display_point(
2838    position: Vector2F,
2839    text_bounds: RectF,
2840    position_map: &PositionMap,
2841) -> Option<DisplayPoint> {
2842    if text_bounds.contains_point(position) {
2843        let (point, target_point) = position_map.point_for_position(text_bounds, position);
2844        if point == target_point {
2845            Some(point)
2846        } else {
2847            None
2848        }
2849    } else {
2850        None
2851    }
2852}
2853
2854fn range_to_bounds(
2855    range: &Range<DisplayPoint>,
2856    content_origin: Vector2F,
2857    scroll_left: f32,
2858    scroll_top: f32,
2859    visible_row_range: &Range<u32>,
2860    line_end_overshoot: f32,
2861    position_map: &PositionMap,
2862) -> impl Iterator<Item = RectF> {
2863    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2864
2865    if range.start == range.end {
2866        return bounds.into_iter();
2867    }
2868
2869    let start_row = visible_row_range.start;
2870    let end_row = visible_row_range.end;
2871
2872    let row_range = if range.end.column() == 0 {
2873        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2874    } else {
2875        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2876    };
2877
2878    let first_y =
2879        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
2880
2881    for (idx, row) in row_range.enumerate() {
2882        let line_layout = &position_map.line_layouts[(row - start_row) as usize].line;
2883
2884        let start_x = if row == range.start.row() {
2885            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
2886                - scroll_left
2887        } else {
2888            content_origin.x() - scroll_left
2889        };
2890
2891        let end_x = if row == range.end.row() {
2892            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
2893        } else {
2894            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
2895        };
2896
2897        bounds.push(RectF::from_points(
2898            vec2f(start_x, first_y + position_map.line_height * idx as f32),
2899            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
2900        ))
2901    }
2902
2903    bounds.into_iter()
2904}
2905
2906pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2907    delta.powf(1.5) / 100.0
2908}
2909
2910fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2911    delta.powf(1.2) / 300.0
2912}
2913
2914#[cfg(test)]
2915mod tests {
2916    use super::*;
2917    use crate::{
2918        display_map::{BlockDisposition, BlockProperties},
2919        editor_tests::{init_test, update_test_language_settings},
2920        Editor, MultiBuffer,
2921    };
2922    use gpui::TestAppContext;
2923    use language::language_settings;
2924    use log::info;
2925    use std::{num::NonZeroU32, sync::Arc};
2926    use util::test::sample_text;
2927
2928    #[gpui::test]
2929    fn test_layout_line_numbers(cx: &mut TestAppContext) {
2930        init_test(cx, |_| {});
2931
2932        let (_, editor) = cx.add_window(|cx| {
2933            let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2934            Editor::new(EditorMode::Full, buffer, None, None, cx)
2935        });
2936        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2937
2938        let layouts = editor.update(cx, |editor, cx| {
2939            let snapshot = editor.snapshot(cx);
2940            element
2941                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
2942                .0
2943        });
2944        assert_eq!(layouts.len(), 6);
2945    }
2946
2947    #[gpui::test]
2948    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
2949        init_test(cx, |_| {});
2950
2951        let (_, editor) = cx.add_window(|cx| {
2952            let buffer = MultiBuffer::build_simple("", cx);
2953            Editor::new(EditorMode::Full, buffer, None, None, cx)
2954        });
2955
2956        editor.update(cx, |editor, cx| {
2957            editor.set_placeholder_text("hello", cx);
2958            editor.insert_blocks(
2959                [BlockProperties {
2960                    style: BlockStyle::Fixed,
2961                    disposition: BlockDisposition::Above,
2962                    height: 3,
2963                    position: Anchor::min(),
2964                    render: Arc::new(|_| Empty::new().into_any()),
2965                }],
2966                None,
2967                cx,
2968            );
2969
2970            // Blur the editor so that it displays placeholder text.
2971            cx.blur();
2972        });
2973
2974        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2975        let (size, mut state) = editor.update(cx, |editor, cx| {
2976            let mut new_parents = Default::default();
2977            let mut notify_views_if_parents_change = Default::default();
2978            let mut layout_cx = LayoutContext::new(
2979                cx,
2980                &mut new_parents,
2981                &mut notify_views_if_parents_change,
2982                false,
2983            );
2984            element.layout(
2985                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2986                editor,
2987                &mut layout_cx,
2988            )
2989        });
2990
2991        assert_eq!(state.position_map.line_layouts.len(), 4);
2992        assert_eq!(
2993            state
2994                .line_number_layouts
2995                .iter()
2996                .map(Option::is_some)
2997                .collect::<Vec<_>>(),
2998            &[false, false, false, true]
2999        );
3000
3001        // Don't panic.
3002        let mut scene = SceneBuilder::new(1.0);
3003        let bounds = RectF::new(Default::default(), size);
3004        editor.update(cx, |editor, cx| {
3005            element.paint(&mut scene, bounds, bounds, &mut state, editor, cx);
3006        });
3007    }
3008
3009    #[gpui::test]
3010    fn test_all_invisibles_drawing(cx: &mut TestAppContext) {
3011        const TAB_SIZE: u32 = 4;
3012
3013        let input_text = "\t \t|\t| a b";
3014        let expected_invisibles = vec![
3015            Invisible::Tab {
3016                line_start_offset: 0,
3017            },
3018            Invisible::Whitespace {
3019                line_offset: TAB_SIZE as usize,
3020            },
3021            Invisible::Tab {
3022                line_start_offset: TAB_SIZE as usize + 1,
3023            },
3024            Invisible::Tab {
3025                line_start_offset: TAB_SIZE as usize * 2 + 1,
3026            },
3027            Invisible::Whitespace {
3028                line_offset: TAB_SIZE as usize * 3 + 1,
3029            },
3030            Invisible::Whitespace {
3031                line_offset: TAB_SIZE as usize * 3 + 3,
3032            },
3033        ];
3034        assert_eq!(
3035            expected_invisibles.len(),
3036            input_text
3037                .chars()
3038                .filter(|initial_char| initial_char.is_whitespace())
3039                .count(),
3040            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3041        );
3042
3043        init_test(cx, |s| {
3044            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3045            s.defaults.tab_size = NonZeroU32::new(TAB_SIZE);
3046        });
3047
3048        let actual_invisibles =
3049            collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, 500.0);
3050
3051        assert_eq!(expected_invisibles, actual_invisibles);
3052    }
3053
3054    #[gpui::test]
3055    fn test_invisibles_dont_appear_in_certain_editors(cx: &mut TestAppContext) {
3056        init_test(cx, |s| {
3057            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3058            s.defaults.tab_size = NonZeroU32::new(4);
3059        });
3060
3061        for editor_mode_without_invisibles in [
3062            EditorMode::SingleLine,
3063            EditorMode::AutoHeight { max_lines: 100 },
3064        ] {
3065            let invisibles = collect_invisibles_from_new_editor(
3066                cx,
3067                editor_mode_without_invisibles,
3068                "\t\t\t| | a b",
3069                500.0,
3070            );
3071            assert!(invisibles.is_empty(),
3072                "For editor mode {editor_mode_without_invisibles:?} no invisibles was expected but got {invisibles:?}");
3073        }
3074    }
3075
3076    #[gpui::test]
3077    fn test_wrapped_invisibles_drawing(cx: &mut TestAppContext) {
3078        let tab_size = 4;
3079        let input_text = "a\tbcd   ".repeat(9);
3080        let repeated_invisibles = [
3081            Invisible::Tab {
3082                line_start_offset: 1,
3083            },
3084            Invisible::Whitespace {
3085                line_offset: tab_size as usize + 3,
3086            },
3087            Invisible::Whitespace {
3088                line_offset: tab_size as usize + 4,
3089            },
3090            Invisible::Whitespace {
3091                line_offset: tab_size as usize + 5,
3092            },
3093        ];
3094        let expected_invisibles = std::iter::once(repeated_invisibles)
3095            .cycle()
3096            .take(9)
3097            .flatten()
3098            .collect::<Vec<_>>();
3099        assert_eq!(
3100            expected_invisibles.len(),
3101            input_text
3102                .chars()
3103                .filter(|initial_char| initial_char.is_whitespace())
3104                .count(),
3105            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3106        );
3107        info!("Expected invisibles: {expected_invisibles:?}");
3108
3109        init_test(cx, |_| {});
3110
3111        // Put the same string with repeating whitespace pattern into editors of various size,
3112        // take deliberately small steps during resizing, to put all whitespace kinds near the wrap point.
3113        let resize_step = 10.0;
3114        let mut editor_width = 200.0;
3115        while editor_width <= 1000.0 {
3116            update_test_language_settings(cx, |s| {
3117                s.defaults.tab_size = NonZeroU32::new(tab_size);
3118                s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3119                s.defaults.preferred_line_length = Some(editor_width as u32);
3120                s.defaults.soft_wrap = Some(language_settings::SoftWrap::PreferredLineLength);
3121            });
3122
3123            let actual_invisibles =
3124                collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, editor_width);
3125
3126            // Whatever the editor size is, ensure it has the same invisible kinds in the same order
3127            // (no good guarantees about the offsets: wrapping could trigger padding and its tests should check the offsets).
3128            let mut i = 0;
3129            for (actual_index, actual_invisible) in actual_invisibles.iter().enumerate() {
3130                i = actual_index;
3131                match expected_invisibles.get(i) {
3132                    Some(expected_invisible) => match (expected_invisible, actual_invisible) {
3133                        (Invisible::Whitespace { .. }, Invisible::Whitespace { .. })
3134                        | (Invisible::Tab { .. }, Invisible::Tab { .. }) => {}
3135                        _ => {
3136                            panic!("At index {i}, expected invisible {expected_invisible:?} does not match actual {actual_invisible:?} by kind. Actual invisibles: {actual_invisibles:?}")
3137                        }
3138                    },
3139                    None => panic!("Unexpected extra invisible {actual_invisible:?} at index {i}"),
3140                }
3141            }
3142            let missing_expected_invisibles = &expected_invisibles[i + 1..];
3143            assert!(
3144                missing_expected_invisibles.is_empty(),
3145                "Missing expected invisibles after index {i}: {missing_expected_invisibles:?}"
3146            );
3147
3148            editor_width += resize_step;
3149        }
3150    }
3151
3152    fn collect_invisibles_from_new_editor(
3153        cx: &mut TestAppContext,
3154        editor_mode: EditorMode,
3155        input_text: &str,
3156        editor_width: f32,
3157    ) -> Vec<Invisible> {
3158        info!(
3159            "Creating editor with mode {editor_mode:?}, width {editor_width} and text '{input_text}'"
3160        );
3161        let (_, editor) = cx.add_window(|cx| {
3162            let buffer = MultiBuffer::build_simple(&input_text, cx);
3163            Editor::new(editor_mode, buffer, None, None, cx)
3164        });
3165
3166        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3167        let (_, layout_state) = editor.update(cx, |editor, cx| {
3168            editor.set_soft_wrap_mode(language_settings::SoftWrap::EditorWidth, cx);
3169            editor.set_wrap_width(Some(editor_width), cx);
3170
3171            let mut new_parents = Default::default();
3172            let mut notify_views_if_parents_change = Default::default();
3173            let mut layout_cx = LayoutContext::new(
3174                cx,
3175                &mut new_parents,
3176                &mut notify_views_if_parents_change,
3177                false,
3178            );
3179            element.layout(
3180                SizeConstraint::new(vec2f(editor_width, 500.), vec2f(editor_width, 500.)),
3181                editor,
3182                &mut layout_cx,
3183            )
3184        });
3185
3186        layout_state
3187            .position_map
3188            .line_layouts
3189            .iter()
3190            .map(|line_with_invisibles| &line_with_invisibles.invisibles)
3191            .flatten()
3192            .cloned()
3193            .collect()
3194    }
3195}