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                for (row, _) in &editor.background_highlights_in_range(
1061                    start_anchor..end_anchor,
1062                    &layout.position_map.snapshot,
1063                    &theme,
1064                ) {
1065                    let start_display = row.start;
1066                    let end_display = row.end;
1067                    let start_y = y_for_row(start_display.row() as f32);
1068                    let mut end_y = y_for_row((end_display.row()) as f32);
1069                    if end_y - start_y < 1. {
1070                        end_y = start_y + 1.;
1071                    }
1072                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1073
1074                    let color = scrollbar_theme.selections;
1075
1076                    let border = Border {
1077                        width: 1.,
1078                        color: style.thumb.border.color,
1079                        overlay: false,
1080                        top: false,
1081                        right: true,
1082                        bottom: false,
1083                        left: true,
1084                    };
1085
1086                    scene.push_quad(Quad {
1087                        bounds,
1088                        background: Some(color),
1089                        border,
1090                        corner_radius: style.thumb.corner_radius,
1091                    })
1092                }
1093            }
1094
1095            if layout.is_singleton && scrollbar_settings.git_diff {
1096                let diff_style = scrollbar_theme.git.clone();
1097                for hunk in layout
1098                    .position_map
1099                    .snapshot
1100                    .buffer_snapshot
1101                    .git_diff_hunks_in_range(0..(max_row.floor() as u32))
1102                {
1103                    let start_display = Point::new(hunk.buffer_range.start, 0)
1104                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1105                    let end_display = Point::new(hunk.buffer_range.end, 0)
1106                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1107                    let start_y = y_for_row(start_display.row() as f32);
1108                    let mut end_y = if hunk.buffer_range.start == hunk.buffer_range.end {
1109                        y_for_row((end_display.row() + 1) as f32)
1110                    } else {
1111                        y_for_row((end_display.row()) as f32)
1112                    };
1113
1114                    if end_y - start_y < 1. {
1115                        end_y = start_y + 1.;
1116                    }
1117                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1118
1119                    let color = match hunk.status() {
1120                        DiffHunkStatus::Added => diff_style.inserted,
1121                        DiffHunkStatus::Modified => diff_style.modified,
1122                        DiffHunkStatus::Removed => diff_style.deleted,
1123                    };
1124
1125                    let border = Border {
1126                        width: 1.,
1127                        color: style.thumb.border.color,
1128                        overlay: false,
1129                        top: false,
1130                        right: true,
1131                        bottom: false,
1132                        left: true,
1133                    };
1134
1135                    scene.push_quad(Quad {
1136                        bounds,
1137                        background: Some(color),
1138                        border,
1139                        corner_radius: style.thumb.corner_radius,
1140                    })
1141                }
1142            }
1143
1144            scene.push_quad(Quad {
1145                bounds: thumb_bounds,
1146                border: style.thumb.border,
1147                background: style.thumb.background_color,
1148                corner_radius: style.thumb.corner_radius,
1149            });
1150        }
1151
1152        scene.push_cursor_region(CursorRegion {
1153            bounds: track_bounds,
1154            style: CursorStyle::Arrow,
1155        });
1156        scene.push_mouse_region(
1157            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1158                .on_move(move |_, editor: &mut Editor, cx| {
1159                    editor.scroll_manager.show_scrollbar(cx);
1160                })
1161                .on_down(MouseButton::Left, {
1162                    let row_range = row_range.clone();
1163                    move |event, editor: &mut Editor, cx| {
1164                        let y = event.position.y();
1165                        if y < thumb_top || thumb_bottom < y {
1166                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1167                            let top_row = center_row
1168                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1169                            let mut position = editor.scroll_position(cx);
1170                            position.set_y(top_row as f32);
1171                            editor.set_scroll_position(position, cx);
1172                        } else {
1173                            editor.scroll_manager.show_scrollbar(cx);
1174                        }
1175                    }
1176                })
1177                .on_drag(MouseButton::Left, {
1178                    move |event, editor: &mut Editor, cx| {
1179                        let y = event.prev_mouse_position.y();
1180                        let new_y = event.position.y();
1181                        if thumb_top < y && y < thumb_bottom {
1182                            let mut position = editor.scroll_position(cx);
1183                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1184                            if position.y() < 0.0 {
1185                                position.set_y(0.);
1186                            }
1187                            editor.set_scroll_position(position, cx);
1188                        }
1189                    }
1190                }),
1191        );
1192    }
1193
1194    #[allow(clippy::too_many_arguments)]
1195    fn paint_highlighted_range(
1196        &self,
1197        scene: &mut SceneBuilder,
1198        range: Range<DisplayPoint>,
1199        color: Color,
1200        corner_radius: f32,
1201        line_end_overshoot: f32,
1202        layout: &LayoutState,
1203        content_origin: Vector2F,
1204        scroll_top: f32,
1205        scroll_left: f32,
1206        bounds: RectF,
1207    ) {
1208        let start_row = layout.visible_display_row_range.start;
1209        let end_row = layout.visible_display_row_range.end;
1210        if range.start != range.end {
1211            let row_range = if range.end.column() == 0 {
1212                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1213            } else {
1214                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1215            };
1216
1217            let highlighted_range = HighlightedRange {
1218                color,
1219                line_height: layout.position_map.line_height,
1220                corner_radius,
1221                start_y: content_origin.y()
1222                    + row_range.start as f32 * layout.position_map.line_height
1223                    - scroll_top,
1224                lines: row_range
1225                    .into_iter()
1226                    .map(|row| {
1227                        let line_layout =
1228                            &layout.position_map.line_layouts[(row - start_row) as usize].line;
1229                        HighlightedRangeLine {
1230                            start_x: if row == range.start.row() {
1231                                content_origin.x()
1232                                    + line_layout.x_for_index(range.start.column() as usize)
1233                                    - scroll_left
1234                            } else {
1235                                content_origin.x() - scroll_left
1236                            },
1237                            end_x: if row == range.end.row() {
1238                                content_origin.x()
1239                                    + line_layout.x_for_index(range.end.column() as usize)
1240                                    - scroll_left
1241                            } else {
1242                                content_origin.x() + line_layout.width() + line_end_overshoot
1243                                    - scroll_left
1244                            },
1245                        }
1246                    })
1247                    .collect(),
1248            };
1249
1250            highlighted_range.paint(bounds, scene);
1251        }
1252    }
1253
1254    fn paint_blocks(
1255        &mut self,
1256        scene: &mut SceneBuilder,
1257        bounds: RectF,
1258        visible_bounds: RectF,
1259        layout: &mut LayoutState,
1260        editor: &mut Editor,
1261        cx: &mut ViewContext<Editor>,
1262    ) {
1263        let scroll_position = layout.position_map.snapshot.scroll_position();
1264        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1265        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1266
1267        for block in &mut layout.blocks {
1268            let mut origin = bounds.origin()
1269                + vec2f(
1270                    0.,
1271                    block.row as f32 * layout.position_map.line_height - scroll_top,
1272                );
1273            if !matches!(block.style, BlockStyle::Sticky) {
1274                origin += vec2f(-scroll_left, 0.);
1275            }
1276            block
1277                .element
1278                .paint(scene, origin, visible_bounds, editor, cx);
1279        }
1280    }
1281
1282    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1283        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1284        let style = &self.style;
1285
1286        cx.text_layout_cache()
1287            .layout_str(
1288                "1".repeat(digit_count).as_str(),
1289                style.text.font_size,
1290                &[(
1291                    digit_count,
1292                    RunStyle {
1293                        font_id: style.text.font_id,
1294                        color: Color::black(),
1295                        underline: Default::default(),
1296                    },
1297                )],
1298            )
1299            .width()
1300    }
1301
1302    //Folds contained in a hunk are ignored apart from shrinking visual size
1303    //If a fold contains any hunks then that fold line is marked as modified
1304    fn layout_git_gutters(
1305        &self,
1306        display_rows: Range<u32>,
1307        snapshot: &EditorSnapshot,
1308    ) -> Vec<DisplayDiffHunk> {
1309        let buffer_snapshot = &snapshot.buffer_snapshot;
1310
1311        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1312            .to_point(snapshot)
1313            .row;
1314        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1315            .to_point(snapshot)
1316            .row;
1317
1318        buffer_snapshot
1319            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row)
1320            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1321            .dedup()
1322            .collect()
1323    }
1324
1325    fn layout_line_numbers(
1326        &self,
1327        rows: Range<u32>,
1328        active_rows: &BTreeMap<u32, bool>,
1329        is_singleton: bool,
1330        snapshot: &EditorSnapshot,
1331        cx: &ViewContext<Editor>,
1332    ) -> (
1333        Vec<Option<text_layout::Line>>,
1334        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1335    ) {
1336        let style = &self.style;
1337        let include_line_numbers = snapshot.mode == EditorMode::Full;
1338        let mut line_number_layouts = Vec::with_capacity(rows.len());
1339        let mut fold_statuses = Vec::with_capacity(rows.len());
1340        let mut line_number = String::new();
1341        for (ix, row) in snapshot
1342            .buffer_rows(rows.start)
1343            .take((rows.end - rows.start) as usize)
1344            .enumerate()
1345        {
1346            let display_row = rows.start + ix as u32;
1347            let (active, color) = if active_rows.contains_key(&display_row) {
1348                (true, style.line_number_active)
1349            } else {
1350                (false, style.line_number)
1351            };
1352            if let Some(buffer_row) = row {
1353                if include_line_numbers {
1354                    line_number.clear();
1355                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1356                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1357                        &line_number,
1358                        style.text.font_size,
1359                        &[(
1360                            line_number.len(),
1361                            RunStyle {
1362                                font_id: style.text.font_id,
1363                                color,
1364                                underline: Default::default(),
1365                            },
1366                        )],
1367                    )));
1368                    fold_statuses.push(
1369                        is_singleton
1370                            .then(|| {
1371                                snapshot
1372                                    .fold_for_line(buffer_row)
1373                                    .map(|fold_status| (fold_status, buffer_row, active))
1374                            })
1375                            .flatten(),
1376                    )
1377                }
1378            } else {
1379                fold_statuses.push(None);
1380                line_number_layouts.push(None);
1381            }
1382        }
1383
1384        (line_number_layouts, fold_statuses)
1385    }
1386
1387    fn layout_lines(
1388        &mut self,
1389        rows: Range<u32>,
1390        line_number_layouts: &[Option<Line>],
1391        snapshot: &EditorSnapshot,
1392        cx: &ViewContext<Editor>,
1393    ) -> Vec<LineWithInvisibles> {
1394        if rows.start >= rows.end {
1395            return Vec::new();
1396        }
1397
1398        // When the editor is empty and unfocused, then show the placeholder.
1399        if snapshot.is_empty() {
1400            let placeholder_style = self
1401                .style
1402                .placeholder_text
1403                .as_ref()
1404                .unwrap_or(&self.style.text);
1405            let placeholder_text = snapshot.placeholder_text();
1406            let placeholder_lines = placeholder_text
1407                .as_ref()
1408                .map_or("", AsRef::as_ref)
1409                .split('\n')
1410                .skip(rows.start as usize)
1411                .chain(iter::repeat(""))
1412                .take(rows.len());
1413            placeholder_lines
1414                .map(|line| {
1415                    cx.text_layout_cache().layout_str(
1416                        line,
1417                        placeholder_style.font_size,
1418                        &[(
1419                            line.len(),
1420                            RunStyle {
1421                                font_id: placeholder_style.font_id,
1422                                color: placeholder_style.color,
1423                                underline: Default::default(),
1424                            },
1425                        )],
1426                    )
1427                })
1428                .map(|line| LineWithInvisibles {
1429                    line,
1430                    invisibles: Vec::new(),
1431                })
1432                .collect()
1433        } else {
1434            let style = &self.style;
1435            let chunks = snapshot
1436                .chunks(rows.clone(), true, Some(style.theme.suggestion))
1437                .map(|chunk| {
1438                    let mut highlight_style = chunk
1439                        .syntax_highlight_id
1440                        .and_then(|id| id.style(&style.syntax));
1441
1442                    if let Some(chunk_highlight) = chunk.highlight_style {
1443                        if let Some(highlight_style) = highlight_style.as_mut() {
1444                            highlight_style.highlight(chunk_highlight);
1445                        } else {
1446                            highlight_style = Some(chunk_highlight);
1447                        }
1448                    }
1449
1450                    let mut diagnostic_highlight = HighlightStyle::default();
1451
1452                    if chunk.is_unnecessary {
1453                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1454                    }
1455
1456                    if let Some(severity) = chunk.diagnostic_severity {
1457                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1458                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1459                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1460                            diagnostic_highlight.underline = Some(Underline {
1461                                color: Some(diagnostic_style.message.text.color),
1462                                thickness: 1.0.into(),
1463                                squiggly: true,
1464                            });
1465                        }
1466                    }
1467
1468                    if let Some(highlight_style) = highlight_style.as_mut() {
1469                        highlight_style.highlight(diagnostic_highlight);
1470                    } else {
1471                        highlight_style = Some(diagnostic_highlight);
1472                    }
1473
1474                    HighlightedChunk {
1475                        chunk: chunk.text,
1476                        style: highlight_style,
1477                        is_tab: chunk.is_tab,
1478                    }
1479                });
1480
1481            LineWithInvisibles::from_chunks(
1482                chunks,
1483                &style.text,
1484                cx.text_layout_cache(),
1485                cx.font_cache(),
1486                MAX_LINE_LEN,
1487                rows.len() as usize,
1488                line_number_layouts,
1489                snapshot.mode,
1490            )
1491        }
1492    }
1493
1494    #[allow(clippy::too_many_arguments)]
1495    fn layout_blocks(
1496        &mut self,
1497        rows: Range<u32>,
1498        snapshot: &EditorSnapshot,
1499        editor_width: f32,
1500        scroll_width: f32,
1501        gutter_padding: f32,
1502        gutter_width: f32,
1503        em_width: f32,
1504        text_x: f32,
1505        line_height: f32,
1506        style: &EditorStyle,
1507        line_layouts: &[LineWithInvisibles],
1508        editor: &mut Editor,
1509        cx: &mut LayoutContext<Editor>,
1510    ) -> (f32, Vec<BlockLayout>) {
1511        let scroll_x = snapshot.scroll_anchor.offset.x();
1512        let (fixed_blocks, non_fixed_blocks) = snapshot
1513            .blocks_in_range(rows.clone())
1514            .partition::<Vec<_>, _>(|(_, block)| match block {
1515                TransformBlock::ExcerptHeader { .. } => false,
1516                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1517            });
1518        let mut render_block = |block: &TransformBlock, width: f32| {
1519            let mut element = match block {
1520                TransformBlock::Custom(block) => {
1521                    let align_to = block
1522                        .position()
1523                        .to_point(&snapshot.buffer_snapshot)
1524                        .to_display_point(snapshot);
1525                    let anchor_x = text_x
1526                        + if rows.contains(&align_to.row()) {
1527                            line_layouts[(align_to.row() - rows.start) as usize]
1528                                .line
1529                                .x_for_index(align_to.column() as usize)
1530                        } else {
1531                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1532                                .x_for_index(align_to.column() as usize)
1533                        };
1534
1535                    block.render(&mut BlockContext {
1536                        view_context: cx,
1537                        anchor_x,
1538                        gutter_padding,
1539                        line_height,
1540                        scroll_x,
1541                        gutter_width,
1542                        em_width,
1543                    })
1544                }
1545                TransformBlock::ExcerptHeader {
1546                    id,
1547                    buffer,
1548                    range,
1549                    starts_new_buffer,
1550                    ..
1551                } => {
1552                    let tooltip_style = theme::current(cx).tooltip.clone();
1553                    let include_root = editor
1554                        .project
1555                        .as_ref()
1556                        .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1557                        .unwrap_or_default();
1558                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1559                        let jump_path = ProjectPath {
1560                            worktree_id: file.worktree_id(cx),
1561                            path: file.path.clone(),
1562                        };
1563                        let jump_anchor = range
1564                            .primary
1565                            .as_ref()
1566                            .map_or(range.context.start, |primary| primary.start);
1567                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1568
1569                        enum JumpIcon {}
1570                        MouseEventHandler::<JumpIcon, _>::new((*id).into(), cx, |state, _| {
1571                            let style = style.jump_icon.style_for(state, false);
1572                            Svg::new("icons/arrow_up_right_8.svg")
1573                                .with_color(style.color)
1574                                .constrained()
1575                                .with_width(style.icon_width)
1576                                .aligned()
1577                                .contained()
1578                                .with_style(style.container)
1579                                .constrained()
1580                                .with_width(style.button_width)
1581                                .with_height(style.button_width)
1582                        })
1583                        .with_cursor_style(CursorStyle::PointingHand)
1584                        .on_click(MouseButton::Left, move |_, editor, cx| {
1585                            if let Some(workspace) = editor
1586                                .workspace
1587                                .as_ref()
1588                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1589                            {
1590                                workspace.update(cx, |workspace, cx| {
1591                                    Editor::jump(
1592                                        workspace,
1593                                        jump_path.clone(),
1594                                        jump_position,
1595                                        jump_anchor,
1596                                        cx,
1597                                    );
1598                                });
1599                            }
1600                        })
1601                        .with_tooltip::<JumpIcon>(
1602                            (*id).into(),
1603                            "Jump to Buffer".to_string(),
1604                            Some(Box::new(crate::OpenExcerpts)),
1605                            tooltip_style.clone(),
1606                            cx,
1607                        )
1608                        .aligned()
1609                        .flex_float()
1610                    });
1611
1612                    if *starts_new_buffer {
1613                        let editor_font_size = style.text.font_size;
1614                        let style = &style.diagnostic_path_header;
1615                        let font_size = (style.text_scale_factor * editor_font_size).round();
1616
1617                        let path = buffer.resolve_file_path(cx, include_root);
1618                        let mut filename = None;
1619                        let mut parent_path = None;
1620                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1621                        if let Some(path) = path {
1622                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1623                            parent_path =
1624                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1625                        }
1626
1627                        Flex::row()
1628                            .with_child(
1629                                Label::new(
1630                                    filename.unwrap_or_else(|| "untitled".to_string()),
1631                                    style.filename.text.clone().with_font_size(font_size),
1632                                )
1633                                .contained()
1634                                .with_style(style.filename.container)
1635                                .aligned(),
1636                            )
1637                            .with_children(parent_path.map(|path| {
1638                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1639                                    .contained()
1640                                    .with_style(style.path.container)
1641                                    .aligned()
1642                            }))
1643                            .with_children(jump_icon)
1644                            .contained()
1645                            .with_style(style.container)
1646                            .with_padding_left(gutter_padding)
1647                            .with_padding_right(gutter_padding)
1648                            .expanded()
1649                            .into_any_named("path header block")
1650                    } else {
1651                        let text_style = style.text.clone();
1652                        Flex::row()
1653                            .with_child(Label::new("", text_style))
1654                            .with_children(jump_icon)
1655                            .contained()
1656                            .with_padding_left(gutter_padding)
1657                            .with_padding_right(gutter_padding)
1658                            .expanded()
1659                            .into_any_named("collapsed context")
1660                    }
1661                }
1662            };
1663
1664            element.layout(
1665                SizeConstraint {
1666                    min: Vector2F::zero(),
1667                    max: vec2f(width, block.height() as f32 * line_height),
1668                },
1669                editor,
1670                cx,
1671            );
1672            element
1673        };
1674
1675        let mut fixed_block_max_width = 0f32;
1676        let mut blocks = Vec::new();
1677        for (row, block) in fixed_blocks {
1678            let element = render_block(block, f32::INFINITY);
1679            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1680            blocks.push(BlockLayout {
1681                row,
1682                element,
1683                style: BlockStyle::Fixed,
1684            });
1685        }
1686        for (row, block) in non_fixed_blocks {
1687            let style = match block {
1688                TransformBlock::Custom(block) => block.style(),
1689                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1690            };
1691            let width = match style {
1692                BlockStyle::Sticky => editor_width,
1693                BlockStyle::Flex => editor_width
1694                    .max(fixed_block_max_width)
1695                    .max(gutter_width + scroll_width),
1696                BlockStyle::Fixed => unreachable!(),
1697            };
1698            let element = render_block(block, width);
1699            blocks.push(BlockLayout {
1700                row,
1701                element,
1702                style,
1703            });
1704        }
1705        (
1706            scroll_width.max(fixed_block_max_width - gutter_width),
1707            blocks,
1708        )
1709    }
1710}
1711
1712struct HighlightedChunk<'a> {
1713    chunk: &'a str,
1714    style: Option<HighlightStyle>,
1715    is_tab: bool,
1716}
1717
1718#[derive(Debug)]
1719pub struct LineWithInvisibles {
1720    pub line: Line,
1721    invisibles: Vec<Invisible>,
1722}
1723
1724impl LineWithInvisibles {
1725    fn from_chunks<'a>(
1726        chunks: impl Iterator<Item = HighlightedChunk<'a>>,
1727        text_style: &TextStyle,
1728        text_layout_cache: &TextLayoutCache,
1729        font_cache: &Arc<FontCache>,
1730        max_line_len: usize,
1731        max_line_count: usize,
1732        line_number_layouts: &[Option<Line>],
1733        editor_mode: EditorMode,
1734    ) -> Vec<Self> {
1735        let mut layouts = Vec::with_capacity(max_line_count);
1736        let mut line = String::new();
1737        let mut invisibles = Vec::new();
1738        let mut styles = Vec::new();
1739        let mut non_whitespace_added = false;
1740        let mut row = 0;
1741        let mut line_exceeded_max_len = false;
1742        for highlighted_chunk in chunks.chain([HighlightedChunk {
1743            chunk: "\n",
1744            style: None,
1745            is_tab: false,
1746        }]) {
1747            for (ix, mut line_chunk) in highlighted_chunk.chunk.split('\n').enumerate() {
1748                if ix > 0 {
1749                    layouts.push(Self {
1750                        line: text_layout_cache.layout_str(&line, text_style.font_size, &styles),
1751                        invisibles: invisibles.drain(..).collect(),
1752                    });
1753
1754                    line.clear();
1755                    styles.clear();
1756                    row += 1;
1757                    line_exceeded_max_len = false;
1758                    non_whitespace_added = false;
1759                    if row == max_line_count {
1760                        return layouts;
1761                    }
1762                }
1763
1764                if !line_chunk.is_empty() && !line_exceeded_max_len {
1765                    let text_style = if let Some(style) = highlighted_chunk.style {
1766                        text_style
1767                            .clone()
1768                            .highlight(style, font_cache)
1769                            .map(Cow::Owned)
1770                            .unwrap_or_else(|_| Cow::Borrowed(text_style))
1771                    } else {
1772                        Cow::Borrowed(text_style)
1773                    };
1774
1775                    if line.len() + line_chunk.len() > max_line_len {
1776                        let mut chunk_len = max_line_len - line.len();
1777                        while !line_chunk.is_char_boundary(chunk_len) {
1778                            chunk_len -= 1;
1779                        }
1780                        line_chunk = &line_chunk[..chunk_len];
1781                        line_exceeded_max_len = true;
1782                    }
1783
1784                    styles.push((
1785                        line_chunk.len(),
1786                        RunStyle {
1787                            font_id: text_style.font_id,
1788                            color: text_style.color,
1789                            underline: text_style.underline,
1790                        },
1791                    ));
1792
1793                    if editor_mode == EditorMode::Full {
1794                        // Line wrap pads its contents with fake whitespaces,
1795                        // avoid printing them
1796                        let inside_wrapped_string = line_number_layouts
1797                            .get(row)
1798                            .and_then(|layout| layout.as_ref())
1799                            .is_none();
1800                        if highlighted_chunk.is_tab {
1801                            if non_whitespace_added || !inside_wrapped_string {
1802                                invisibles.push(Invisible::Tab {
1803                                    line_start_offset: line.len(),
1804                                });
1805                            }
1806                        } else {
1807                            invisibles.extend(
1808                                line_chunk
1809                                    .chars()
1810                                    .enumerate()
1811                                    .filter(|(_, line_char)| {
1812                                        let is_whitespace = line_char.is_whitespace();
1813                                        non_whitespace_added |= !is_whitespace;
1814                                        is_whitespace
1815                                            && (non_whitespace_added || !inside_wrapped_string)
1816                                    })
1817                                    .map(|(whitespace_index, _)| Invisible::Whitespace {
1818                                        line_offset: line.len() + whitespace_index,
1819                                    }),
1820                            )
1821                        }
1822                    }
1823
1824                    line.push_str(line_chunk);
1825                }
1826            }
1827        }
1828
1829        layouts
1830    }
1831
1832    fn draw(
1833        &self,
1834        layout: &LayoutState,
1835        row: u32,
1836        scroll_top: f32,
1837        scene: &mut SceneBuilder,
1838        content_origin: Vector2F,
1839        scroll_left: f32,
1840        visible_text_bounds: RectF,
1841        whitespace_setting: ShowWhitespaceSetting,
1842        selection_ranges: &[Range<DisplayPoint>],
1843        visible_bounds: RectF,
1844        cx: &mut ViewContext<Editor>,
1845    ) {
1846        let line_height = layout.position_map.line_height;
1847        let line_y = row as f32 * line_height - scroll_top;
1848
1849        self.line.paint(
1850            scene,
1851            content_origin + vec2f(-scroll_left, line_y),
1852            visible_text_bounds,
1853            line_height,
1854            cx,
1855        );
1856
1857        self.draw_invisibles(
1858            &selection_ranges,
1859            layout,
1860            content_origin,
1861            scroll_left,
1862            line_y,
1863            row,
1864            scene,
1865            visible_bounds,
1866            line_height,
1867            whitespace_setting,
1868            cx,
1869        );
1870    }
1871
1872    fn draw_invisibles(
1873        &self,
1874        selection_ranges: &[Range<DisplayPoint>],
1875        layout: &LayoutState,
1876        content_origin: Vector2F,
1877        scroll_left: f32,
1878        line_y: f32,
1879        row: u32,
1880        scene: &mut SceneBuilder,
1881        visible_bounds: RectF,
1882        line_height: f32,
1883        whitespace_setting: ShowWhitespaceSetting,
1884        cx: &mut ViewContext<Editor>,
1885    ) {
1886        let allowed_invisibles_regions = match whitespace_setting {
1887            ShowWhitespaceSetting::None => return,
1888            ShowWhitespaceSetting::Selection => Some(selection_ranges),
1889            ShowWhitespaceSetting::All => None,
1890        };
1891
1892        for invisible in &self.invisibles {
1893            let (&token_offset, invisible_symbol) = match invisible {
1894                Invisible::Tab { line_start_offset } => (line_start_offset, &layout.tab_invisible),
1895                Invisible::Whitespace { line_offset } => (line_offset, &layout.space_invisible),
1896            };
1897
1898            let x_offset = self.line.x_for_index(token_offset);
1899            let invisible_offset =
1900                (layout.position_map.em_width - invisible_symbol.width()).max(0.0) / 2.0;
1901            let origin = content_origin + vec2f(-scroll_left + x_offset + invisible_offset, line_y);
1902
1903            if let Some(allowed_regions) = allowed_invisibles_regions {
1904                let invisible_point = DisplayPoint::new(row, token_offset as u32);
1905                if !allowed_regions
1906                    .iter()
1907                    .any(|region| region.start <= invisible_point && invisible_point < region.end)
1908                {
1909                    continue;
1910                }
1911            }
1912            invisible_symbol.paint(scene, origin, visible_bounds, line_height, cx);
1913        }
1914    }
1915}
1916
1917#[derive(Debug, Clone, Copy, PartialEq, Eq)]
1918enum Invisible {
1919    Tab { line_start_offset: usize },
1920    Whitespace { line_offset: usize },
1921}
1922
1923impl Element<Editor> for EditorElement {
1924    type LayoutState = LayoutState;
1925    type PaintState = ();
1926
1927    fn layout(
1928        &mut self,
1929        constraint: SizeConstraint,
1930        editor: &mut Editor,
1931        cx: &mut LayoutContext<Editor>,
1932    ) -> (Vector2F, Self::LayoutState) {
1933        let mut size = constraint.max;
1934        if size.x().is_infinite() {
1935            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1936        }
1937
1938        let snapshot = editor.snapshot(cx);
1939        let style = self.style.clone();
1940        let line_height = style.text.line_height(cx.font_cache());
1941
1942        let gutter_padding;
1943        let gutter_width;
1944        let gutter_margin;
1945        if snapshot.show_gutter {
1946            let em_width = style.text.em_width(cx.font_cache());
1947            gutter_padding = (em_width * style.gutter_padding_factor).round();
1948            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1949            gutter_margin = -style.text.descent(cx.font_cache());
1950        } else {
1951            gutter_padding = 0.0;
1952            gutter_width = 0.0;
1953            gutter_margin = 0.0;
1954        };
1955
1956        let text_width = size.x() - gutter_width;
1957        let em_width = style.text.em_width(cx.font_cache());
1958        let em_advance = style.text.em_advance(cx.font_cache());
1959        let overscroll = vec2f(em_width, 0.);
1960        let snapshot = {
1961            editor.set_visible_line_count(size.y() / line_height);
1962
1963            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
1964            let wrap_width = match editor.soft_wrap_mode(cx) {
1965                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
1966                SoftWrap::EditorWidth => editor_width,
1967                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
1968            };
1969
1970            if editor.set_wrap_width(Some(wrap_width), cx) {
1971                editor.snapshot(cx)
1972            } else {
1973                snapshot
1974            }
1975        };
1976
1977        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1978        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1979            size.set_y(
1980                scroll_height
1981                    .min(constraint.max_along(Axis::Vertical))
1982                    .max(constraint.min_along(Axis::Vertical))
1983                    .min(line_height * max_lines as f32),
1984            )
1985        } else if let EditorMode::SingleLine = snapshot.mode {
1986            size.set_y(
1987                line_height
1988                    .min(constraint.max_along(Axis::Vertical))
1989                    .max(constraint.min_along(Axis::Vertical)),
1990            )
1991        } else if size.y().is_infinite() {
1992            size.set_y(scroll_height);
1993        }
1994        let gutter_size = vec2f(gutter_width, size.y());
1995        let text_size = vec2f(text_width, size.y());
1996
1997        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
1998        let mut snapshot = editor.snapshot(cx);
1999
2000        let scroll_position = snapshot.scroll_position();
2001        // The scroll position is a fractional point, the whole number of which represents
2002        // the top of the window in terms of display rows.
2003        let start_row = scroll_position.y() as u32;
2004        let height_in_lines = size.y() / line_height;
2005        let max_row = snapshot.max_point().row();
2006
2007        // Add 1 to ensure selections bleed off screen
2008        let end_row = 1 + cmp::min(
2009            (scroll_position.y() + height_in_lines).ceil() as u32,
2010            max_row,
2011        );
2012
2013        let start_anchor = if start_row == 0 {
2014            Anchor::min()
2015        } else {
2016            snapshot
2017                .buffer_snapshot
2018                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
2019        };
2020        let end_anchor = if end_row > max_row {
2021            Anchor::max()
2022        } else {
2023            snapshot
2024                .buffer_snapshot
2025                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
2026        };
2027
2028        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
2029        let mut active_rows = BTreeMap::new();
2030        let mut fold_ranges = Vec::new();
2031        let is_singleton = editor.is_singleton(cx);
2032
2033        let highlighted_rows = editor.highlighted_rows();
2034        let theme = theme::current(cx);
2035        let highlighted_ranges = editor.background_highlights_in_range(
2036            start_anchor..end_anchor,
2037            &snapshot.display_snapshot,
2038            theme.as_ref(),
2039        );
2040
2041        fold_ranges.extend(
2042            snapshot
2043                .folds_in_range(start_anchor..end_anchor)
2044                .map(|anchor| {
2045                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
2046                    (
2047                        start.row,
2048                        start.to_display_point(&snapshot.display_snapshot)
2049                            ..anchor.end.to_display_point(&snapshot),
2050                    )
2051                }),
2052        );
2053
2054        let mut remote_selections = HashMap::default();
2055        for (replica_id, line_mode, cursor_shape, selection) in snapshot
2056            .buffer_snapshot
2057            .remote_selections_in_range(&(start_anchor..end_anchor))
2058        {
2059            // The local selections match the leader's selections.
2060            if Some(replica_id) == editor.leader_replica_id {
2061                continue;
2062            }
2063            remote_selections
2064                .entry(replica_id)
2065                .or_insert(Vec::new())
2066                .push(SelectionLayout::new(
2067                    selection,
2068                    line_mode,
2069                    cursor_shape,
2070                    &snapshot.display_snapshot,
2071                ));
2072        }
2073        selections.extend(remote_selections);
2074
2075        if editor.show_local_selections {
2076            let mut local_selections = editor
2077                .selections
2078                .disjoint_in_range(start_anchor..end_anchor, cx);
2079            local_selections.extend(editor.selections.pending(cx));
2080            for selection in &local_selections {
2081                let is_empty = selection.start == selection.end;
2082                let selection_start = snapshot.prev_line_boundary(selection.start).1;
2083                let selection_end = snapshot.next_line_boundary(selection.end).1;
2084                for row in cmp::max(selection_start.row(), start_row)
2085                    ..=cmp::min(selection_end.row(), end_row)
2086                {
2087                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
2088                    *contains_non_empty_selection |= !is_empty;
2089                }
2090            }
2091
2092            // Render the local selections in the leader's color when following.
2093            let local_replica_id = editor
2094                .leader_replica_id
2095                .unwrap_or_else(|| editor.replica_id(cx));
2096
2097            selections.push((
2098                local_replica_id,
2099                local_selections
2100                    .into_iter()
2101                    .map(|selection| {
2102                        SelectionLayout::new(
2103                            selection,
2104                            editor.selections.line_mode,
2105                            editor.cursor_shape,
2106                            &snapshot.display_snapshot,
2107                        )
2108                    })
2109                    .collect(),
2110            ));
2111        }
2112
2113        let scrollbar_settings = &settings::get::<EditorSettings>(cx).scrollbar;
2114        let show_scrollbars = match scrollbar_settings.show {
2115            ShowScrollbar::Auto => {
2116                // Git
2117                (is_singleton && scrollbar_settings.git_diff && snapshot.buffer_snapshot.has_git_diffs())
2118                // Scrollmanager
2119                || editor.scroll_manager.scrollbars_visible()
2120            }
2121            ShowScrollbar::System => editor.scroll_manager.scrollbars_visible(),
2122            ShowScrollbar::Always => true,
2123            ShowScrollbar::Never => false,
2124        };
2125
2126        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
2127            .into_iter()
2128            .map(|(id, fold)| {
2129                let color = self
2130                    .style
2131                    .folds
2132                    .ellipses
2133                    .background
2134                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize), false)
2135                    .color;
2136
2137                (id, fold, color)
2138            })
2139            .collect();
2140
2141        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
2142            start_row..end_row,
2143            &active_rows,
2144            is_singleton,
2145            &snapshot,
2146            cx,
2147        );
2148
2149        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
2150
2151        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
2152
2153        let mut max_visible_line_width = 0.0;
2154        let line_layouts =
2155            self.layout_lines(start_row..end_row, &line_number_layouts, &snapshot, cx);
2156        for line_with_invisibles in &line_layouts {
2157            if line_with_invisibles.line.width() > max_visible_line_width {
2158                max_visible_line_width = line_with_invisibles.line.width();
2159            }
2160        }
2161
2162        let style = self.style.clone();
2163        let longest_line_width = layout_line(
2164            snapshot.longest_row(),
2165            &snapshot,
2166            &style,
2167            cx.text_layout_cache(),
2168        )
2169        .width();
2170        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
2171        let em_width = style.text.em_width(cx.font_cache());
2172        let (scroll_width, blocks) = self.layout_blocks(
2173            start_row..end_row,
2174            &snapshot,
2175            size.x(),
2176            scroll_width,
2177            gutter_padding,
2178            gutter_width,
2179            em_width,
2180            gutter_width + gutter_margin,
2181            line_height,
2182            &style,
2183            &line_layouts,
2184            editor,
2185            cx,
2186        );
2187
2188        let scroll_max = vec2f(
2189            ((scroll_width - text_size.x()) / em_width).max(0.0),
2190            max_row as f32,
2191        );
2192
2193        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
2194
2195        let autoscrolled = if autoscroll_horizontally {
2196            editor.autoscroll_horizontally(
2197                start_row,
2198                text_size.x(),
2199                scroll_width,
2200                em_width,
2201                &line_layouts,
2202                cx,
2203            )
2204        } else {
2205            false
2206        };
2207
2208        if clamped || autoscrolled {
2209            snapshot = editor.snapshot(cx);
2210        }
2211
2212        let newest_selection_head = editor
2213            .selections
2214            .newest::<usize>(cx)
2215            .head()
2216            .to_display_point(&snapshot);
2217        let style = editor.style(cx);
2218
2219        let mut context_menu = None;
2220        let mut code_actions_indicator = None;
2221        if (start_row..end_row).contains(&newest_selection_head.row()) {
2222            if editor.context_menu_visible() {
2223                context_menu = editor.render_context_menu(newest_selection_head, style.clone(), cx);
2224            }
2225
2226            let active = matches!(
2227                editor.context_menu,
2228                Some(crate::ContextMenu::CodeActions(_))
2229            );
2230
2231            code_actions_indicator = editor
2232                .render_code_actions_indicator(&style, active, cx)
2233                .map(|indicator| (newest_selection_head.row(), indicator));
2234        }
2235
2236        let visible_rows = start_row..start_row + line_layouts.len() as u32;
2237        let mut hover = editor
2238            .hover_state
2239            .render(&snapshot, &style, visible_rows, cx);
2240        let mode = editor.mode;
2241
2242        let mut fold_indicators = editor.render_fold_indicators(
2243            fold_statuses,
2244            &style,
2245            editor.gutter_hovered,
2246            line_height,
2247            gutter_margin,
2248            cx,
2249        );
2250
2251        if let Some((_, context_menu)) = context_menu.as_mut() {
2252            context_menu.layout(
2253                SizeConstraint {
2254                    min: Vector2F::zero(),
2255                    max: vec2f(
2256                        cx.window_size().x() * 0.7,
2257                        (12. * line_height).min((size.y() - line_height) / 2.),
2258                    ),
2259                },
2260                editor,
2261                cx,
2262            );
2263        }
2264
2265        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
2266            indicator.layout(
2267                SizeConstraint::strict_along(
2268                    Axis::Vertical,
2269                    line_height * style.code_actions.vertical_scale,
2270                ),
2271                editor,
2272                cx,
2273            );
2274        }
2275
2276        for fold_indicator in fold_indicators.iter_mut() {
2277            if let Some(indicator) = fold_indicator.as_mut() {
2278                indicator.layout(
2279                    SizeConstraint::strict_along(
2280                        Axis::Vertical,
2281                        line_height * style.code_actions.vertical_scale,
2282                    ),
2283                    editor,
2284                    cx,
2285                );
2286            }
2287        }
2288
2289        if let Some((_, hover_popovers)) = hover.as_mut() {
2290            for hover_popover in hover_popovers.iter_mut() {
2291                hover_popover.layout(
2292                    SizeConstraint {
2293                        min: Vector2F::zero(),
2294                        max: vec2f(
2295                            (120. * em_width) // Default size
2296                                .min(size.x() / 2.) // Shrink to half of the editor width
2297                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
2298                            (16. * line_height) // Default size
2299                                .min(size.y() / 2.) // Shrink to half of the editor height
2300                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
2301                        ),
2302                    },
2303                    editor,
2304                    cx,
2305                );
2306            }
2307        }
2308
2309        let invisible_symbol_font_size = self.style.text.font_size / 2.0;
2310        let invisible_symbol_style = RunStyle {
2311            color: self.style.whitespace,
2312            font_id: self.style.text.font_id,
2313            underline: Default::default(),
2314        };
2315
2316        (
2317            size,
2318            LayoutState {
2319                mode,
2320                position_map: Arc::new(PositionMap {
2321                    size,
2322                    scroll_max,
2323                    line_layouts,
2324                    line_height,
2325                    em_width,
2326                    em_advance,
2327                    snapshot,
2328                }),
2329                visible_display_row_range: start_row..end_row,
2330                gutter_size,
2331                gutter_padding,
2332                text_size,
2333                scrollbar_row_range,
2334                show_scrollbars,
2335                is_singleton,
2336                max_row,
2337                gutter_margin,
2338                active_rows,
2339                highlighted_rows,
2340                highlighted_ranges,
2341                fold_ranges,
2342                line_number_layouts,
2343                display_hunks,
2344                blocks,
2345                selections,
2346                context_menu,
2347                code_actions_indicator,
2348                fold_indicators,
2349                tab_invisible: cx.text_layout_cache().layout_str(
2350                    "",
2351                    invisible_symbol_font_size,
2352                    &[("".len(), invisible_symbol_style)],
2353                ),
2354                space_invisible: cx.text_layout_cache().layout_str(
2355                    "",
2356                    invisible_symbol_font_size,
2357                    &[("".len(), invisible_symbol_style)],
2358                ),
2359                hover_popovers: hover,
2360            },
2361        )
2362    }
2363
2364    fn paint(
2365        &mut self,
2366        scene: &mut SceneBuilder,
2367        bounds: RectF,
2368        visible_bounds: RectF,
2369        layout: &mut Self::LayoutState,
2370        editor: &mut Editor,
2371        cx: &mut ViewContext<Editor>,
2372    ) -> Self::PaintState {
2373        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2374        scene.push_layer(Some(visible_bounds));
2375
2376        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2377        let text_bounds = RectF::new(
2378            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2379            layout.text_size,
2380        );
2381
2382        Self::attach_mouse_handlers(
2383            scene,
2384            &layout.position_map,
2385            layout.hover_popovers.is_some(),
2386            visible_bounds,
2387            text_bounds,
2388            gutter_bounds,
2389            bounds,
2390            cx,
2391        );
2392
2393        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2394        if layout.gutter_size.x() > 0. {
2395            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2396        }
2397        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2398
2399        scene.push_layer(Some(bounds));
2400        if !layout.blocks.is_empty() {
2401            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2402        }
2403        self.paint_scrollbar(scene, bounds, layout, cx, &editor);
2404        scene.pop_layer();
2405
2406        scene.pop_layer();
2407    }
2408
2409    fn rect_for_text_range(
2410        &self,
2411        range_utf16: Range<usize>,
2412        bounds: RectF,
2413        _: RectF,
2414        layout: &Self::LayoutState,
2415        _: &Self::PaintState,
2416        _: &Editor,
2417        _: &ViewContext<Editor>,
2418    ) -> Option<RectF> {
2419        let text_bounds = RectF::new(
2420            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2421            layout.text_size,
2422        );
2423        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2424        let scroll_position = layout.position_map.snapshot.scroll_position();
2425        let start_row = scroll_position.y() as u32;
2426        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2427        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2428
2429        let range_start = OffsetUtf16(range_utf16.start)
2430            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2431        if range_start.row() < start_row {
2432            return None;
2433        }
2434
2435        let line = &layout
2436            .position_map
2437            .line_layouts
2438            .get((range_start.row() - start_row) as usize)?
2439            .line;
2440        let range_start_x = line.x_for_index(range_start.column() as usize);
2441        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2442        Some(RectF::new(
2443            content_origin
2444                + vec2f(
2445                    range_start_x,
2446                    range_start_y + layout.position_map.line_height,
2447                )
2448                - vec2f(scroll_left, scroll_top),
2449            vec2f(
2450                layout.position_map.em_width,
2451                layout.position_map.line_height,
2452            ),
2453        ))
2454    }
2455
2456    fn debug(
2457        &self,
2458        bounds: RectF,
2459        _: &Self::LayoutState,
2460        _: &Self::PaintState,
2461        _: &Editor,
2462        _: &ViewContext<Editor>,
2463    ) -> json::Value {
2464        json!({
2465            "type": "BufferElement",
2466            "bounds": bounds.to_json()
2467        })
2468    }
2469}
2470
2471type BufferRow = u32;
2472
2473pub struct LayoutState {
2474    position_map: Arc<PositionMap>,
2475    gutter_size: Vector2F,
2476    gutter_padding: f32,
2477    gutter_margin: f32,
2478    text_size: Vector2F,
2479    mode: EditorMode,
2480    visible_display_row_range: Range<u32>,
2481    active_rows: BTreeMap<u32, bool>,
2482    highlighted_rows: Option<Range<u32>>,
2483    line_number_layouts: Vec<Option<text_layout::Line>>,
2484    display_hunks: Vec<DisplayDiffHunk>,
2485    blocks: Vec<BlockLayout>,
2486    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2487    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2488    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2489    scrollbar_row_range: Range<f32>,
2490    show_scrollbars: bool,
2491    is_singleton: bool,
2492    max_row: u32,
2493    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2494    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2495    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2496    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2497    tab_invisible: Line,
2498    space_invisible: Line,
2499}
2500
2501struct PositionMap {
2502    size: Vector2F,
2503    line_height: f32,
2504    scroll_max: Vector2F,
2505    em_width: f32,
2506    em_advance: f32,
2507    line_layouts: Vec<LineWithInvisibles>,
2508    snapshot: EditorSnapshot,
2509}
2510
2511impl PositionMap {
2512    /// Returns two display points:
2513    /// 1. The nearest *valid* position in the editor
2514    /// 2. An unclipped, potentially *invalid* position that maps directly to
2515    ///    the given pixel position.
2516    fn point_for_position(
2517        &self,
2518        text_bounds: RectF,
2519        position: Vector2F,
2520    ) -> (DisplayPoint, DisplayPoint) {
2521        let scroll_position = self.snapshot.scroll_position();
2522        let position = position - text_bounds.origin();
2523        let y = position.y().max(0.0).min(self.size.y());
2524        let x = position.x() + (scroll_position.x() * self.em_width);
2525        let row = (y / self.line_height + scroll_position.y()) as u32;
2526        let (column, x_overshoot) = if let Some(line) = self
2527            .line_layouts
2528            .get(row as usize - scroll_position.y() as usize)
2529            .map(|line_with_spaces| &line_with_spaces.line)
2530        {
2531            if let Some(ix) = line.index_for_x(x) {
2532                (ix as u32, 0.0)
2533            } else {
2534                (line.len() as u32, 0f32.max(x - line.width()))
2535            }
2536        } else {
2537            (0, x)
2538        };
2539
2540        let mut target_point = DisplayPoint::new(row, column);
2541        let point = self.snapshot.clip_point(target_point, Bias::Left);
2542        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2543
2544        (point, target_point)
2545    }
2546}
2547
2548struct BlockLayout {
2549    row: u32,
2550    element: AnyElement<Editor>,
2551    style: BlockStyle,
2552}
2553
2554fn layout_line(
2555    row: u32,
2556    snapshot: &EditorSnapshot,
2557    style: &EditorStyle,
2558    layout_cache: &TextLayoutCache,
2559) -> text_layout::Line {
2560    let mut line = snapshot.line(row);
2561
2562    if line.len() > MAX_LINE_LEN {
2563        let mut len = MAX_LINE_LEN;
2564        while !line.is_char_boundary(len) {
2565            len -= 1;
2566        }
2567
2568        line.truncate(len);
2569    }
2570
2571    layout_cache.layout_str(
2572        &line,
2573        style.text.font_size,
2574        &[(
2575            snapshot.line_len(row) as usize,
2576            RunStyle {
2577                font_id: style.text.font_id,
2578                color: Color::black(),
2579                underline: Default::default(),
2580            },
2581        )],
2582    )
2583}
2584
2585#[derive(Debug)]
2586pub struct Cursor {
2587    origin: Vector2F,
2588    block_width: f32,
2589    line_height: f32,
2590    color: Color,
2591    shape: CursorShape,
2592    block_text: Option<Line>,
2593}
2594
2595impl Cursor {
2596    pub fn new(
2597        origin: Vector2F,
2598        block_width: f32,
2599        line_height: f32,
2600        color: Color,
2601        shape: CursorShape,
2602        block_text: Option<Line>,
2603    ) -> Cursor {
2604        Cursor {
2605            origin,
2606            block_width,
2607            line_height,
2608            color,
2609            shape,
2610            block_text,
2611        }
2612    }
2613
2614    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2615        RectF::new(
2616            self.origin + origin,
2617            vec2f(self.block_width, self.line_height),
2618        )
2619    }
2620
2621    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2622        let bounds = match self.shape {
2623            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2624            CursorShape::Block | CursorShape::Hollow => RectF::new(
2625                self.origin + origin,
2626                vec2f(self.block_width, self.line_height),
2627            ),
2628            CursorShape::Underscore => RectF::new(
2629                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2630                vec2f(self.block_width, 2.0),
2631            ),
2632        };
2633
2634        //Draw background or border quad
2635        if matches!(self.shape, CursorShape::Hollow) {
2636            scene.push_quad(Quad {
2637                bounds,
2638                background: None,
2639                border: Border::all(1., self.color),
2640                corner_radius: 0.,
2641            });
2642        } else {
2643            scene.push_quad(Quad {
2644                bounds,
2645                background: Some(self.color),
2646                border: Default::default(),
2647                corner_radius: 0.,
2648            });
2649        }
2650
2651        if let Some(block_text) = &self.block_text {
2652            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2653        }
2654    }
2655
2656    pub fn shape(&self) -> CursorShape {
2657        self.shape
2658    }
2659}
2660
2661#[derive(Debug)]
2662pub struct HighlightedRange {
2663    pub start_y: f32,
2664    pub line_height: f32,
2665    pub lines: Vec<HighlightedRangeLine>,
2666    pub color: Color,
2667    pub corner_radius: f32,
2668}
2669
2670#[derive(Debug)]
2671pub struct HighlightedRangeLine {
2672    pub start_x: f32,
2673    pub end_x: f32,
2674}
2675
2676impl HighlightedRange {
2677    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2678        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2679            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2680            self.paint_lines(
2681                self.start_y + self.line_height,
2682                &self.lines[1..],
2683                bounds,
2684                scene,
2685            );
2686        } else {
2687            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2688        }
2689    }
2690
2691    fn paint_lines(
2692        &self,
2693        start_y: f32,
2694        lines: &[HighlightedRangeLine],
2695        bounds: RectF,
2696        scene: &mut SceneBuilder,
2697    ) {
2698        if lines.is_empty() {
2699            return;
2700        }
2701
2702        let mut path = PathBuilder::new();
2703        let first_line = lines.first().unwrap();
2704        let last_line = lines.last().unwrap();
2705
2706        let first_top_left = vec2f(first_line.start_x, start_y);
2707        let first_top_right = vec2f(first_line.end_x, start_y);
2708
2709        let curve_height = vec2f(0., self.corner_radius);
2710        let curve_width = |start_x: f32, end_x: f32| {
2711            let max = (end_x - start_x) / 2.;
2712            let width = if max < self.corner_radius {
2713                max
2714            } else {
2715                self.corner_radius
2716            };
2717
2718            vec2f(width, 0.)
2719        };
2720
2721        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2722        path.reset(first_top_right - top_curve_width);
2723        path.curve_to(first_top_right + curve_height, first_top_right);
2724
2725        let mut iter = lines.iter().enumerate().peekable();
2726        while let Some((ix, line)) = iter.next() {
2727            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2728
2729            if let Some((_, next_line)) = iter.peek() {
2730                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2731
2732                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2733                    Ordering::Equal => {
2734                        path.line_to(bottom_right);
2735                    }
2736                    Ordering::Less => {
2737                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2738                        path.line_to(bottom_right - curve_height);
2739                        if self.corner_radius > 0. {
2740                            path.curve_to(bottom_right - curve_width, bottom_right);
2741                        }
2742                        path.line_to(next_top_right + curve_width);
2743                        if self.corner_radius > 0. {
2744                            path.curve_to(next_top_right + curve_height, next_top_right);
2745                        }
2746                    }
2747                    Ordering::Greater => {
2748                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2749                        path.line_to(bottom_right - curve_height);
2750                        if self.corner_radius > 0. {
2751                            path.curve_to(bottom_right + curve_width, bottom_right);
2752                        }
2753                        path.line_to(next_top_right - curve_width);
2754                        if self.corner_radius > 0. {
2755                            path.curve_to(next_top_right + curve_height, next_top_right);
2756                        }
2757                    }
2758                }
2759            } else {
2760                let curve_width = curve_width(line.start_x, line.end_x);
2761                path.line_to(bottom_right - curve_height);
2762                if self.corner_radius > 0. {
2763                    path.curve_to(bottom_right - curve_width, bottom_right);
2764                }
2765
2766                let bottom_left = vec2f(line.start_x, bottom_right.y());
2767                path.line_to(bottom_left + curve_width);
2768                if self.corner_radius > 0. {
2769                    path.curve_to(bottom_left - curve_height, bottom_left);
2770                }
2771            }
2772        }
2773
2774        if first_line.start_x > last_line.start_x {
2775            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2776            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2777            path.line_to(second_top_left + curve_height);
2778            if self.corner_radius > 0. {
2779                path.curve_to(second_top_left + curve_width, second_top_left);
2780            }
2781            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2782            path.line_to(first_bottom_left - curve_width);
2783            if self.corner_radius > 0. {
2784                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2785            }
2786        }
2787
2788        path.line_to(first_top_left + curve_height);
2789        if self.corner_radius > 0. {
2790            path.curve_to(first_top_left + top_curve_width, first_top_left);
2791        }
2792        path.line_to(first_top_right - top_curve_width);
2793
2794        scene.push_path(path.build(self.color, Some(bounds)));
2795    }
2796}
2797
2798fn position_to_display_point(
2799    position: Vector2F,
2800    text_bounds: RectF,
2801    position_map: &PositionMap,
2802) -> Option<DisplayPoint> {
2803    if text_bounds.contains_point(position) {
2804        let (point, target_point) = position_map.point_for_position(text_bounds, position);
2805        if point == target_point {
2806            Some(point)
2807        } else {
2808            None
2809        }
2810    } else {
2811        None
2812    }
2813}
2814
2815fn range_to_bounds(
2816    range: &Range<DisplayPoint>,
2817    content_origin: Vector2F,
2818    scroll_left: f32,
2819    scroll_top: f32,
2820    visible_row_range: &Range<u32>,
2821    line_end_overshoot: f32,
2822    position_map: &PositionMap,
2823) -> impl Iterator<Item = RectF> {
2824    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2825
2826    if range.start == range.end {
2827        return bounds.into_iter();
2828    }
2829
2830    let start_row = visible_row_range.start;
2831    let end_row = visible_row_range.end;
2832
2833    let row_range = if range.end.column() == 0 {
2834        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2835    } else {
2836        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2837    };
2838
2839    let first_y =
2840        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
2841
2842    for (idx, row) in row_range.enumerate() {
2843        let line_layout = &position_map.line_layouts[(row - start_row) as usize].line;
2844
2845        let start_x = if row == range.start.row() {
2846            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
2847                - scroll_left
2848        } else {
2849            content_origin.x() - scroll_left
2850        };
2851
2852        let end_x = if row == range.end.row() {
2853            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
2854        } else {
2855            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
2856        };
2857
2858        bounds.push(RectF::from_points(
2859            vec2f(start_x, first_y + position_map.line_height * idx as f32),
2860            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
2861        ))
2862    }
2863
2864    bounds.into_iter()
2865}
2866
2867pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2868    delta.powf(1.5) / 100.0
2869}
2870
2871fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2872    delta.powf(1.2) / 300.0
2873}
2874
2875#[cfg(test)]
2876mod tests {
2877    use super::*;
2878    use crate::{
2879        display_map::{BlockDisposition, BlockProperties},
2880        editor_tests::{init_test, update_test_settings},
2881        Editor, MultiBuffer,
2882    };
2883    use gpui::TestAppContext;
2884    use language::language_settings;
2885    use log::info;
2886    use std::{num::NonZeroU32, sync::Arc};
2887    use util::test::sample_text;
2888
2889    #[gpui::test]
2890    fn test_layout_line_numbers(cx: &mut TestAppContext) {
2891        init_test(cx, |_| {});
2892
2893        let (_, editor) = cx.add_window(|cx| {
2894            let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2895            Editor::new(EditorMode::Full, buffer, None, None, cx)
2896        });
2897        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2898
2899        let layouts = editor.update(cx, |editor, cx| {
2900            let snapshot = editor.snapshot(cx);
2901            element
2902                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
2903                .0
2904        });
2905        assert_eq!(layouts.len(), 6);
2906    }
2907
2908    #[gpui::test]
2909    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
2910        init_test(cx, |_| {});
2911
2912        let (_, editor) = cx.add_window(|cx| {
2913            let buffer = MultiBuffer::build_simple("", cx);
2914            Editor::new(EditorMode::Full, buffer, None, None, cx)
2915        });
2916
2917        editor.update(cx, |editor, cx| {
2918            editor.set_placeholder_text("hello", cx);
2919            editor.insert_blocks(
2920                [BlockProperties {
2921                    style: BlockStyle::Fixed,
2922                    disposition: BlockDisposition::Above,
2923                    height: 3,
2924                    position: Anchor::min(),
2925                    render: Arc::new(|_| Empty::new().into_any()),
2926                }],
2927                None,
2928                cx,
2929            );
2930
2931            // Blur the editor so that it displays placeholder text.
2932            cx.blur();
2933        });
2934
2935        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2936        let (size, mut state) = editor.update(cx, |editor, cx| {
2937            let mut new_parents = Default::default();
2938            let mut notify_views_if_parents_change = Default::default();
2939            let mut layout_cx = LayoutContext::new(
2940                cx,
2941                &mut new_parents,
2942                &mut notify_views_if_parents_change,
2943                false,
2944            );
2945            element.layout(
2946                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2947                editor,
2948                &mut layout_cx,
2949            )
2950        });
2951
2952        assert_eq!(state.position_map.line_layouts.len(), 4);
2953        assert_eq!(
2954            state
2955                .line_number_layouts
2956                .iter()
2957                .map(Option::is_some)
2958                .collect::<Vec<_>>(),
2959            &[false, false, false, true]
2960        );
2961
2962        // Don't panic.
2963        let mut scene = SceneBuilder::new(1.0);
2964        let bounds = RectF::new(Default::default(), size);
2965        editor.update(cx, |editor, cx| {
2966            element.paint(&mut scene, bounds, bounds, &mut state, editor, cx);
2967        });
2968    }
2969
2970    #[gpui::test]
2971    fn test_all_invisibles_drawing(cx: &mut TestAppContext) {
2972        const TAB_SIZE: u32 = 4;
2973
2974        let input_text = "\t \t|\t| a b";
2975        let expected_invisibles = vec![
2976            Invisible::Tab {
2977                line_start_offset: 0,
2978            },
2979            Invisible::Whitespace {
2980                line_offset: TAB_SIZE as usize,
2981            },
2982            Invisible::Tab {
2983                line_start_offset: TAB_SIZE as usize + 1,
2984            },
2985            Invisible::Tab {
2986                line_start_offset: TAB_SIZE as usize * 2 + 1,
2987            },
2988            Invisible::Whitespace {
2989                line_offset: TAB_SIZE as usize * 3 + 1,
2990            },
2991            Invisible::Whitespace {
2992                line_offset: TAB_SIZE as usize * 3 + 3,
2993            },
2994        ];
2995        assert_eq!(
2996            expected_invisibles.len(),
2997            input_text
2998                .chars()
2999                .filter(|initial_char| initial_char.is_whitespace())
3000                .count(),
3001            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3002        );
3003
3004        init_test(cx, |s| {
3005            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3006            s.defaults.tab_size = NonZeroU32::new(TAB_SIZE);
3007        });
3008
3009        let actual_invisibles =
3010            collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, 500.0);
3011
3012        assert_eq!(expected_invisibles, actual_invisibles);
3013    }
3014
3015    #[gpui::test]
3016    fn test_invisibles_dont_appear_in_certain_editors(cx: &mut TestAppContext) {
3017        init_test(cx, |s| {
3018            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3019            s.defaults.tab_size = NonZeroU32::new(4);
3020        });
3021
3022        for editor_mode_without_invisibles in [
3023            EditorMode::SingleLine,
3024            EditorMode::AutoHeight { max_lines: 100 },
3025        ] {
3026            let invisibles = collect_invisibles_from_new_editor(
3027                cx,
3028                editor_mode_without_invisibles,
3029                "\t\t\t| | a b",
3030                500.0,
3031            );
3032            assert!(invisibles.is_empty(),
3033                "For editor mode {editor_mode_without_invisibles:?} no invisibles was expected but got {invisibles:?}");
3034        }
3035    }
3036
3037    #[gpui::test]
3038    fn test_wrapped_invisibles_drawing(cx: &mut TestAppContext) {
3039        let tab_size = 4;
3040        let input_text = "a\tbcd   ".repeat(9);
3041        let repeated_invisibles = [
3042            Invisible::Tab {
3043                line_start_offset: 1,
3044            },
3045            Invisible::Whitespace {
3046                line_offset: tab_size as usize + 3,
3047            },
3048            Invisible::Whitespace {
3049                line_offset: tab_size as usize + 4,
3050            },
3051            Invisible::Whitespace {
3052                line_offset: tab_size as usize + 5,
3053            },
3054        ];
3055        let expected_invisibles = std::iter::once(repeated_invisibles)
3056            .cycle()
3057            .take(9)
3058            .flatten()
3059            .collect::<Vec<_>>();
3060        assert_eq!(
3061            expected_invisibles.len(),
3062            input_text
3063                .chars()
3064                .filter(|initial_char| initial_char.is_whitespace())
3065                .count(),
3066            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3067        );
3068        info!("Expected invisibles: {expected_invisibles:?}");
3069
3070        init_test(cx, |_| {});
3071
3072        // Put the same string with repeating whitespace pattern into editors of various size,
3073        // take deliberately small steps during resizing, to put all whitespace kinds near the wrap point.
3074        let resize_step = 10.0;
3075        let mut editor_width = 200.0;
3076        while editor_width <= 1000.0 {
3077            update_test_settings(cx, |s| {
3078                s.defaults.tab_size = NonZeroU32::new(tab_size);
3079                s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3080                s.defaults.preferred_line_length = Some(editor_width as u32);
3081                s.defaults.soft_wrap = Some(language_settings::SoftWrap::PreferredLineLength);
3082            });
3083
3084            let actual_invisibles =
3085                collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, editor_width);
3086
3087            // Whatever the editor size is, ensure it has the same invisible kinds in the same order
3088            // (no good guarantees about the offsets: wrapping could trigger padding and its tests should check the offsets).
3089            let mut i = 0;
3090            for (actual_index, actual_invisible) in actual_invisibles.iter().enumerate() {
3091                i = actual_index;
3092                match expected_invisibles.get(i) {
3093                    Some(expected_invisible) => match (expected_invisible, actual_invisible) {
3094                        (Invisible::Whitespace { .. }, Invisible::Whitespace { .. })
3095                        | (Invisible::Tab { .. }, Invisible::Tab { .. }) => {}
3096                        _ => {
3097                            panic!("At index {i}, expected invisible {expected_invisible:?} does not match actual {actual_invisible:?} by kind. Actual invisibles: {actual_invisibles:?}")
3098                        }
3099                    },
3100                    None => panic!("Unexpected extra invisible {actual_invisible:?} at index {i}"),
3101                }
3102            }
3103            let missing_expected_invisibles = &expected_invisibles[i + 1..];
3104            assert!(
3105                missing_expected_invisibles.is_empty(),
3106                "Missing expected invisibles after index {i}: {missing_expected_invisibles:?}"
3107            );
3108
3109            editor_width += resize_step;
3110        }
3111    }
3112
3113    fn collect_invisibles_from_new_editor(
3114        cx: &mut TestAppContext,
3115        editor_mode: EditorMode,
3116        input_text: &str,
3117        editor_width: f32,
3118    ) -> Vec<Invisible> {
3119        info!(
3120            "Creating editor with mode {editor_mode:?}, width {editor_width} and text '{input_text}'"
3121        );
3122        let (_, editor) = cx.add_window(|cx| {
3123            let buffer = MultiBuffer::build_simple(&input_text, cx);
3124            Editor::new(editor_mode, buffer, None, None, cx)
3125        });
3126
3127        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3128        let (_, layout_state) = editor.update(cx, |editor, cx| {
3129            editor.set_soft_wrap_mode(language_settings::SoftWrap::EditorWidth, cx);
3130            editor.set_wrap_width(Some(editor_width), cx);
3131
3132            let mut new_parents = Default::default();
3133            let mut notify_views_if_parents_change = Default::default();
3134            let mut layout_cx = LayoutContext::new(
3135                cx,
3136                &mut new_parents,
3137                &mut notify_views_if_parents_change,
3138                false,
3139            );
3140            element.layout(
3141                SizeConstraint::new(vec2f(editor_width, 500.), vec2f(editor_width, 500.)),
3142                editor,
3143                &mut layout_cx,
3144            )
3145        });
3146
3147        layout_state
3148            .position_map
3149            .line_layouts
3150            .iter()
3151            .map(|line_with_invisibles| &line_with_invisibles.invisibles)
3152            .flatten()
3153            .cloned()
3154            .collect()
3155    }
3156}