element.rs

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