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, 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, LayoutContext, MouseRegion,
  34    Quad, SceneBuilder, SizeConstraint, ViewContext, WindowContext,
  35};
  36use itertools::Itertools;
  37use json::json;
  38use language::{Bias, CursorShape, DiagnosticSeverity, OffsetUtf16, Selection};
  39use project::ProjectPath;
  40use settings::{GitGutter, Settings};
  41use smallvec::SmallVec;
  42use std::{
  43    cmp::{self, Ordering},
  44    fmt::Write,
  45    iter,
  46    ops::Range,
  47    sync::Arc,
  48};
  49use workspace::item::Item;
  50
  51enum FoldMarkers {}
  52
  53struct SelectionLayout {
  54    head: DisplayPoint,
  55    cursor_shape: CursorShape,
  56    range: Range<DisplayPoint>,
  57}
  58
  59impl SelectionLayout {
  60    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  61        selection: Selection<T>,
  62        line_mode: bool,
  63        cursor_shape: CursorShape,
  64        map: &DisplaySnapshot,
  65    ) -> Self {
  66        if line_mode {
  67            let selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  68            let point_range = map.expand_to_line(selection.range());
  69            Self {
  70                head: selection.head().to_display_point(map),
  71                cursor_shape,
  72                range: point_range.start.to_display_point(map)
  73                    ..point_range.end.to_display_point(map),
  74            }
  75        } else {
  76            let selection = selection.map(|p| p.to_display_point(map));
  77            Self {
  78                head: selection.head(),
  79                cursor_shape,
  80                range: selection.range(),
  81            }
  82        }
  83    }
  84}
  85
  86#[derive(Clone)]
  87pub struct EditorElement {
  88    style: Arc<EditorStyle>,
  89}
  90
  91impl EditorElement {
  92    pub fn new(style: EditorStyle) -> Self {
  93        Self {
  94            style: Arc::new(style),
  95        }
  96    }
  97
  98    fn attach_mouse_handlers(
  99        scene: &mut SceneBuilder,
 100        position_map: &Arc<PositionMap>,
 101        has_popovers: bool,
 102        visible_bounds: RectF,
 103        text_bounds: RectF,
 104        gutter_bounds: RectF,
 105        bounds: RectF,
 106        cx: &mut ViewContext<Editor>,
 107    ) {
 108        enum EditorElementMouseHandlers {}
 109        scene.push_mouse_region(
 110            MouseRegion::new::<EditorElementMouseHandlers>(
 111                cx.view_id(),
 112                cx.view_id(),
 113                visible_bounds,
 114            )
 115            .on_down(MouseButton::Left, {
 116                let position_map = position_map.clone();
 117                move |event, editor, cx| {
 118                    if !Self::mouse_down(
 119                        editor,
 120                        event.platform_event,
 121                        position_map.as_ref(),
 122                        text_bounds,
 123                        gutter_bounds,
 124                        cx,
 125                    ) {
 126                        cx.propagate_event();
 127                    }
 128                }
 129            })
 130            .on_down(MouseButton::Right, {
 131                let position_map = position_map.clone();
 132                move |event, editor, cx| {
 133                    if !Self::mouse_right_down(
 134                        editor,
 135                        event.position,
 136                        position_map.as_ref(),
 137                        text_bounds,
 138                        cx,
 139                    ) {
 140                        cx.propagate_event();
 141                    }
 142                }
 143            })
 144            .on_up(MouseButton::Left, {
 145                let position_map = position_map.clone();
 146                move |event, editor, cx| {
 147                    if !Self::mouse_up(
 148                        editor,
 149                        event.position,
 150                        event.cmd,
 151                        event.shift,
 152                        position_map.as_ref(),
 153                        text_bounds,
 154                        cx,
 155                    ) {
 156                        cx.propagate_event()
 157                    }
 158                }
 159            })
 160            .on_drag(MouseButton::Left, {
 161                let position_map = position_map.clone();
 162                move |event, editor, cx| {
 163                    if !Self::mouse_dragged(
 164                        editor,
 165                        event.platform_event,
 166                        position_map.as_ref(),
 167                        text_bounds,
 168                        cx,
 169                    ) {
 170                        cx.propagate_event()
 171                    }
 172                }
 173            })
 174            .on_move({
 175                let position_map = position_map.clone();
 176                move |event, editor, cx| {
 177                    if !Self::mouse_moved(
 178                        editor,
 179                        event.platform_event,
 180                        &position_map,
 181                        text_bounds,
 182                        cx,
 183                    ) {
 184                        cx.propagate_event()
 185                    }
 186                }
 187            })
 188            .on_move_out(move |_, editor: &mut Editor, cx| {
 189                if has_popovers {
 190                    hide_hover(editor, cx);
 191                }
 192            })
 193            .on_scroll({
 194                let position_map = position_map.clone();
 195                move |event, editor, cx| {
 196                    if !Self::scroll(
 197                        editor,
 198                        event.position,
 199                        *event.delta.raw(),
 200                        event.delta.precise(),
 201                        &position_map,
 202                        bounds,
 203                        cx,
 204                    ) {
 205                        cx.propagate_event()
 206                    }
 207                }
 208            }),
 209        );
 210
 211        enum GutterHandlers {}
 212        scene.push_mouse_region(
 213            MouseRegion::new::<GutterHandlers>(cx.view_id(), cx.view_id() + 1, gutter_bounds)
 214                .on_hover(|hover, editor: &mut Editor, cx| {
 215                    editor.gutter_hover(
 216                        &GutterHover {
 217                            hovered: hover.started,
 218                        },
 219                        cx,
 220                    );
 221                }),
 222        )
 223    }
 224
 225    fn mouse_down(
 226        editor: &mut Editor,
 227        MouseButtonEvent {
 228            position,
 229            modifiers:
 230                Modifiers {
 231                    shift,
 232                    ctrl,
 233                    alt,
 234                    cmd,
 235                    ..
 236                },
 237            mut click_count,
 238            ..
 239        }: MouseButtonEvent,
 240        position_map: &PositionMap,
 241        text_bounds: RectF,
 242        gutter_bounds: RectF,
 243        cx: &mut EventContext<Editor>,
 244    ) -> bool {
 245        if gutter_bounds.contains_point(position) {
 246            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 247        } else if !text_bounds.contains_point(position) {
 248            return false;
 249        }
 250
 251        let (position, target_position) = position_map.point_for_position(text_bounds, position);
 252
 253        if shift && alt {
 254            editor.select(
 255                SelectPhase::BeginColumnar {
 256                    position,
 257                    goal_column: target_position.column(),
 258                },
 259                cx,
 260            );
 261        } else if shift && !ctrl && !alt && !cmd {
 262            editor.select(
 263                SelectPhase::Extend {
 264                    position,
 265                    click_count,
 266                },
 267                cx,
 268            );
 269        } else {
 270            editor.select(
 271                SelectPhase::Begin {
 272                    position,
 273                    add: alt,
 274                    click_count,
 275                },
 276                cx,
 277            );
 278        }
 279
 280        true
 281    }
 282
 283    fn mouse_right_down(
 284        editor: &mut Editor,
 285        position: Vector2F,
 286        position_map: &PositionMap,
 287        text_bounds: RectF,
 288        cx: &mut EventContext<Editor>,
 289    ) -> bool {
 290        if !text_bounds.contains_point(position) {
 291            return false;
 292        }
 293
 294        let (point, _) = position_map.point_for_position(text_bounds, position);
 295        mouse_context_menu::deploy_context_menu(editor, position, point, cx);
 296        true
 297    }
 298
 299    fn mouse_up(
 300        editor: &mut Editor,
 301        position: Vector2F,
 302        cmd: bool,
 303        shift: bool,
 304        position_map: &PositionMap,
 305        text_bounds: RectF,
 306        cx: &mut EventContext<Editor>,
 307    ) -> bool {
 308        let end_selection = editor.has_pending_selection();
 309        let pending_nonempty_selections = editor.has_pending_nonempty_selection();
 310
 311        if end_selection {
 312            editor.select(SelectPhase::End, cx);
 313        }
 314
 315        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 316            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 317
 318            if point == target_point {
 319                if shift {
 320                    go_to_fetched_type_definition(editor, point, cx);
 321                } else {
 322                    go_to_fetched_definition(editor, point, cx);
 323                }
 324
 325                return true;
 326            }
 327        }
 328
 329        end_selection
 330    }
 331
 332    fn mouse_dragged(
 333        editor: &mut Editor,
 334        MouseMovedEvent {
 335            modifiers: Modifiers { cmd, shift, .. },
 336            position,
 337            ..
 338        }: MouseMovedEvent,
 339        position_map: &PositionMap,
 340        text_bounds: RectF,
 341        cx: &mut EventContext<Editor>,
 342    ) -> bool {
 343        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 344        // Don't trigger hover popover if mouse is hovering over context menu
 345        let point = if text_bounds.contains_point(position) {
 346            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 347            if point == target_point {
 348                Some(point)
 349            } else {
 350                None
 351            }
 352        } else {
 353            None
 354        };
 355
 356        update_go_to_definition_link(editor, point, cmd, shift, cx);
 357
 358        if editor.has_pending_selection() {
 359            let mut scroll_delta = Vector2F::zero();
 360
 361            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 362            let top = text_bounds.origin_y() + vertical_margin;
 363            let bottom = text_bounds.lower_left().y() - vertical_margin;
 364            if position.y() < top {
 365                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 366            }
 367            if position.y() > bottom {
 368                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 369            }
 370
 371            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 372            let left = text_bounds.origin_x() + horizontal_margin;
 373            let right = text_bounds.upper_right().x() - horizontal_margin;
 374            if position.x() < left {
 375                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 376                    left - position.x(),
 377                ))
 378            }
 379            if position.x() > right {
 380                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 381                    position.x() - right,
 382                ))
 383            }
 384
 385            let (position, target_position) =
 386                position_map.point_for_position(text_bounds, position);
 387
 388            editor.select(
 389                SelectPhase::Update {
 390                    position,
 391                    goal_column: target_position.column(),
 392                    scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 393                        .clamp(Vector2F::zero(), position_map.scroll_max),
 394                },
 395                cx,
 396            );
 397            hover_at(editor, point, cx);
 398            true
 399        } else {
 400            hover_at(editor, point, cx);
 401            false
 402        }
 403    }
 404
 405    fn mouse_moved(
 406        editor: &mut Editor,
 407        MouseMovedEvent {
 408            modifiers: Modifiers { shift, cmd, .. },
 409            position,
 410            ..
 411        }: MouseMovedEvent,
 412        position_map: &PositionMap,
 413        text_bounds: RectF,
 414        cx: &mut ViewContext<Editor>,
 415    ) -> bool {
 416        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 417        // Don't trigger hover popover if mouse is hovering over context menu
 418        let point = position_to_display_point(position, text_bounds, position_map);
 419
 420        update_go_to_definition_link(editor, point, cmd, shift, cx);
 421        hover_at(editor, point, cx);
 422
 423        true
 424    }
 425
 426    fn scroll(
 427        editor: &mut Editor,
 428        position: Vector2F,
 429        mut delta: Vector2F,
 430        precise: bool,
 431        position_map: &PositionMap,
 432        bounds: RectF,
 433        cx: &mut ViewContext<Editor>,
 434    ) -> bool {
 435        if !bounds.contains_point(position) {
 436            return false;
 437        }
 438
 439        let line_height = position_map.line_height;
 440        let max_glyph_width = position_map.em_width;
 441
 442        let axis = if precise {
 443            //Trackpad
 444            position_map.snapshot.ongoing_scroll.filter(&mut delta)
 445        } else {
 446            //Not trackpad
 447            delta *= vec2f(max_glyph_width, line_height);
 448            None //Resets ongoing scroll
 449        };
 450
 451        let scroll_position = position_map.snapshot.scroll_position();
 452        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 453        let y = (scroll_position.y() * line_height - delta.y()) / line_height;
 454        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 455        editor.scroll(scroll_position, axis, cx);
 456
 457        true
 458    }
 459
 460    fn paint_background(
 461        &self,
 462        scene: &mut SceneBuilder,
 463        gutter_bounds: RectF,
 464        text_bounds: RectF,
 465        layout: &LayoutState,
 466    ) {
 467        let bounds = gutter_bounds.union_rect(text_bounds);
 468        let scroll_top =
 469            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 470        scene.push_quad(Quad {
 471            bounds: gutter_bounds,
 472            background: Some(self.style.gutter_background),
 473            border: Border::new(0., Color::transparent_black()),
 474            corner_radius: 0.,
 475        });
 476        scene.push_quad(Quad {
 477            bounds: text_bounds,
 478            background: Some(self.style.background),
 479            border: Border::new(0., Color::transparent_black()),
 480            corner_radius: 0.,
 481        });
 482
 483        if let EditorMode::Full = layout.mode {
 484            let mut active_rows = layout.active_rows.iter().peekable();
 485            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 486                let mut end_row = *start_row;
 487                while active_rows.peek().map_or(false, |r| {
 488                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 489                }) {
 490                    active_rows.next().unwrap();
 491                    end_row += 1;
 492                }
 493
 494                if !contains_non_empty_selection {
 495                    let origin = vec2f(
 496                        bounds.origin_x(),
 497                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 498                            - scroll_top,
 499                    );
 500                    let size = vec2f(
 501                        bounds.width(),
 502                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 503                    );
 504                    scene.push_quad(Quad {
 505                        bounds: RectF::new(origin, size),
 506                        background: Some(self.style.active_line_background),
 507                        border: Border::default(),
 508                        corner_radius: 0.,
 509                    });
 510                }
 511            }
 512
 513            if let Some(highlighted_rows) = &layout.highlighted_rows {
 514                let origin = vec2f(
 515                    bounds.origin_x(),
 516                    bounds.origin_y()
 517                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 518                        - scroll_top,
 519                );
 520                let size = vec2f(
 521                    bounds.width(),
 522                    layout.position_map.line_height * highlighted_rows.len() as f32,
 523                );
 524                scene.push_quad(Quad {
 525                    bounds: RectF::new(origin, size),
 526                    background: Some(self.style.highlighted_line_background),
 527                    border: Border::default(),
 528                    corner_radius: 0.,
 529                });
 530            }
 531        }
 532    }
 533
 534    fn paint_gutter(
 535        &mut self,
 536        scene: &mut SceneBuilder,
 537        bounds: RectF,
 538        visible_bounds: RectF,
 539        layout: &mut LayoutState,
 540        editor: &mut Editor,
 541        cx: &mut ViewContext<Editor>,
 542    ) {
 543        let line_height = layout.position_map.line_height;
 544
 545        let scroll_position = layout.position_map.snapshot.scroll_position();
 546        let scroll_top = scroll_position.y() * line_height;
 547
 548        let show_gutter = matches!(
 549            &cx.global::<Settings>()
 550                .git_overrides
 551                .git_gutter
 552                .unwrap_or_default(),
 553            GitGutter::TrackedFiles
 554        );
 555
 556        if show_gutter {
 557            Self::paint_diff_hunks(scene, bounds, layout, cx);
 558        }
 559
 560        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 561            if let Some(line) = line {
 562                let line_origin = bounds.origin()
 563                    + vec2f(
 564                        bounds.width() - line.width() - layout.gutter_padding,
 565                        ix as f32 * line_height - (scroll_top % line_height),
 566                    );
 567
 568                line.paint(scene, line_origin, visible_bounds, line_height, cx);
 569            }
 570        }
 571
 572        for (ix, fold_indicator) in layout.fold_indicators.iter_mut().enumerate() {
 573            if let Some(indicator) = fold_indicator.as_mut() {
 574                let position = vec2f(
 575                    bounds.width() - layout.gutter_padding,
 576                    ix as f32 * line_height - (scroll_top % line_height),
 577                );
 578                let centering_offset = vec2f(
 579                    (layout.gutter_padding + layout.gutter_margin - indicator.size().x()) / 2.,
 580                    (line_height - indicator.size().y()) / 2.,
 581                );
 582
 583                let indicator_origin = bounds.origin() + position + centering_offset;
 584
 585                indicator.paint(scene, indicator_origin, visible_bounds, editor, cx);
 586            }
 587        }
 588
 589        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 590            let mut x = 0.;
 591            let mut y = *row as f32 * line_height - scroll_top;
 592            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 593            y += (line_height - indicator.size().y()) / 2.;
 594            indicator.paint(
 595                scene,
 596                bounds.origin() + vec2f(x, y),
 597                visible_bounds,
 598                editor,
 599                cx,
 600            );
 601        }
 602    }
 603
 604    fn paint_diff_hunks(
 605        scene: &mut SceneBuilder,
 606        bounds: RectF,
 607        layout: &mut LayoutState,
 608        cx: &mut ViewContext<Editor>,
 609    ) {
 610        let diff_style = &cx.global::<Settings>().theme.editor.diff.clone();
 611        let line_height = layout.position_map.line_height;
 612
 613        let scroll_position = layout.position_map.snapshot.scroll_position();
 614        let scroll_top = scroll_position.y() * line_height;
 615
 616        for hunk in &layout.display_hunks {
 617            let (display_row_range, status) = match hunk {
 618                //TODO: This rendering is entirely a horrible hack
 619                &DisplayDiffHunk::Folded { display_row: row } => {
 620                    let start_y = row as f32 * line_height - scroll_top;
 621                    let end_y = start_y + line_height;
 622
 623                    let width = diff_style.removed_width_em * line_height;
 624                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 625                    let highlight_size = vec2f(width * 2., end_y - start_y);
 626                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 627
 628                    scene.push_quad(Quad {
 629                        bounds: highlight_bounds,
 630                        background: Some(diff_style.modified),
 631                        border: Border::new(0., Color::transparent_black()),
 632                        corner_radius: 1. * line_height,
 633                    });
 634
 635                    continue;
 636                }
 637
 638                DisplayDiffHunk::Unfolded {
 639                    display_row_range,
 640                    status,
 641                } => (display_row_range, status),
 642            };
 643
 644            let color = match status {
 645                DiffHunkStatus::Added => diff_style.inserted,
 646                DiffHunkStatus::Modified => diff_style.modified,
 647
 648                //TODO: This rendering is entirely a horrible hack
 649                DiffHunkStatus::Removed => {
 650                    let row = *display_row_range.start();
 651
 652                    let offset = line_height / 2.;
 653                    let start_y = row as f32 * line_height - offset - scroll_top;
 654                    let end_y = start_y + line_height;
 655
 656                    let width = diff_style.removed_width_em * line_height;
 657                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 658                    let highlight_size = vec2f(width * 2., end_y - start_y);
 659                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 660
 661                    scene.push_quad(Quad {
 662                        bounds: highlight_bounds,
 663                        background: Some(diff_style.deleted),
 664                        border: Border::new(0., Color::transparent_black()),
 665                        corner_radius: 1. * line_height,
 666                    });
 667
 668                    continue;
 669                }
 670            };
 671
 672            let start_row = *display_row_range.start();
 673            let end_row = *display_row_range.end();
 674
 675            let start_y = start_row as f32 * line_height - scroll_top;
 676            let end_y = end_row as f32 * line_height - scroll_top + line_height;
 677
 678            let width = diff_style.width_em * line_height;
 679            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 680            let highlight_size = vec2f(width * 2., end_y - start_y);
 681            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 682
 683            scene.push_quad(Quad {
 684                bounds: highlight_bounds,
 685                background: Some(color),
 686                border: Border::new(0., Color::transparent_black()),
 687                corner_radius: diff_style.corner_radius * line_height,
 688            });
 689        }
 690    }
 691
 692    fn paint_text(
 693        &mut self,
 694        scene: &mut SceneBuilder,
 695        bounds: RectF,
 696        visible_bounds: RectF,
 697        layout: &mut LayoutState,
 698        editor: &mut Editor,
 699        cx: &mut ViewContext<Editor>,
 700    ) {
 701        let style = &self.style;
 702        let local_replica_id = editor.replica_id(cx);
 703        let scroll_position = layout.position_map.snapshot.scroll_position();
 704        let start_row = layout.visible_display_row_range.start;
 705        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 706        let max_glyph_width = layout.position_map.em_width;
 707        let scroll_left = scroll_position.x() * max_glyph_width;
 708        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 709        let line_end_overshoot = 0.15 * layout.position_map.line_height;
 710
 711        scene.push_layer(Some(bounds));
 712
 713        scene.push_cursor_region(CursorRegion {
 714            bounds,
 715            style: if !editor.link_go_to_definition_state.definitions.is_empty() {
 716                CursorStyle::PointingHand
 717            } else {
 718                CursorStyle::IBeam
 719            },
 720        });
 721
 722        let fold_corner_radius =
 723            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
 724        for (id, range, color) in layout.fold_ranges.iter() {
 725            self.paint_highlighted_range(
 726                scene,
 727                range.clone(),
 728                *color,
 729                fold_corner_radius,
 730                fold_corner_radius * 2.,
 731                layout,
 732                content_origin,
 733                scroll_top,
 734                scroll_left,
 735                bounds,
 736            );
 737
 738            for bound in range_to_bounds(
 739                &range,
 740                content_origin,
 741                scroll_left,
 742                scroll_top,
 743                &layout.visible_display_row_range,
 744                line_end_overshoot,
 745                &layout.position_map,
 746            ) {
 747                scene.push_cursor_region(CursorRegion {
 748                    bounds: bound,
 749                    style: CursorStyle::PointingHand,
 750                });
 751
 752                let display_row = range.start.row();
 753
 754                let buffer_row = DisplayPoint::new(display_row, 0)
 755                    .to_point(&layout.position_map.snapshot.display_snapshot)
 756                    .row;
 757
 758                scene.push_mouse_region(
 759                    MouseRegion::new::<FoldMarkers>(cx.view_id(), *id as usize, bound)
 760                        .on_click(MouseButton::Left, move |_, editor: &mut Editor, cx| {
 761                            editor.unfold_at(&UnfoldAt { buffer_row }, cx)
 762                        })
 763                        .with_notify_on_hover(true)
 764                        .with_notify_on_click(true),
 765                )
 766            }
 767        }
 768
 769        for (range, color) in &layout.highlighted_ranges {
 770            self.paint_highlighted_range(
 771                scene,
 772                range.clone(),
 773                *color,
 774                0.,
 775                line_end_overshoot,
 776                layout,
 777                content_origin,
 778                scroll_top,
 779                scroll_left,
 780                bounds,
 781            );
 782        }
 783
 784        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 785        let corner_radius = 0.15 * layout.position_map.line_height;
 786
 787        for (replica_id, selections) in &layout.selections {
 788            let selection_style = style.replica_selection_style(*replica_id);
 789
 790            for selection in selections {
 791                self.paint_highlighted_range(
 792                    scene,
 793                    selection.range.clone(),
 794                    selection_style.selection,
 795                    corner_radius,
 796                    corner_radius * 2.,
 797                    layout,
 798                    content_origin,
 799                    scroll_top,
 800                    scroll_left,
 801                    bounds,
 802                );
 803
 804                if editor.show_local_cursors(cx) || *replica_id != local_replica_id {
 805                    let cursor_position = selection.head;
 806                    if layout
 807                        .visible_display_row_range
 808                        .contains(&cursor_position.row())
 809                    {
 810                        let cursor_row_layout = &layout.position_map.line_layouts
 811                            [(cursor_position.row() - start_row) as usize];
 812                        let cursor_column = cursor_position.column() as usize;
 813
 814                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 815                        let mut block_width =
 816                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 817                        if block_width == 0.0 {
 818                            block_width = layout.position_map.em_width;
 819                        }
 820                        let block_text = if let CursorShape::Block = selection.cursor_shape {
 821                            layout
 822                                .position_map
 823                                .snapshot
 824                                .chars_at(cursor_position)
 825                                .next()
 826                                .and_then(|(character, _)| {
 827                                    let font_id =
 828                                        cursor_row_layout.font_for_index(cursor_column)?;
 829                                    let text = character.to_string();
 830
 831                                    Some(cx.text_layout_cache().layout_str(
 832                                        &text,
 833                                        cursor_row_layout.font_size(),
 834                                        &[(
 835                                            text.len(),
 836                                            RunStyle {
 837                                                font_id,
 838                                                color: style.background,
 839                                                underline: Default::default(),
 840                                            },
 841                                        )],
 842                                    ))
 843                                })
 844                        } else {
 845                            None
 846                        };
 847
 848                        let x = cursor_character_x - scroll_left;
 849                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 850                            - scroll_top;
 851                        cursors.push(Cursor {
 852                            color: selection_style.cursor,
 853                            block_width,
 854                            origin: vec2f(x, y),
 855                            line_height: layout.position_map.line_height,
 856                            shape: selection.cursor_shape,
 857                            block_text,
 858                        });
 859                    }
 860                }
 861            }
 862        }
 863
 864        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 865            // Draw glyphs
 866            for (ix, line) in layout.position_map.line_layouts.iter().enumerate() {
 867                let row = start_row + ix as u32;
 868                line.paint(
 869                    scene,
 870                    content_origin
 871                        + vec2f(
 872                            -scroll_left,
 873                            row as f32 * layout.position_map.line_height - scroll_top,
 874                        ),
 875                    visible_text_bounds,
 876                    layout.position_map.line_height,
 877                    cx,
 878                );
 879            }
 880        }
 881
 882        scene.paint_layer(Some(bounds), |scene| {
 883            for cursor in cursors {
 884                cursor.paint(scene, content_origin, cx);
 885            }
 886        });
 887
 888        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 889            scene.push_stacking_context(None, None);
 890            let cursor_row_layout =
 891                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 892            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 893            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
 894            let mut list_origin = content_origin + vec2f(x, y);
 895            let list_width = context_menu.size().x();
 896            let list_height = context_menu.size().y();
 897
 898            // Snap the right edge of the list to the right edge of the window if
 899            // its horizontal bounds overflow.
 900            if list_origin.x() + list_width > cx.window_size().x() {
 901                list_origin.set_x((cx.window_size().x() - list_width).max(0.));
 902            }
 903
 904            if list_origin.y() + list_height > bounds.max_y() {
 905                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
 906            }
 907
 908            context_menu.paint(
 909                scene,
 910                list_origin,
 911                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 912                editor,
 913                cx,
 914            );
 915
 916            scene.pop_stacking_context();
 917        }
 918
 919        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
 920            scene.push_stacking_context(None, None);
 921
 922            // This is safe because we check on layout whether the required row is available
 923            let hovered_row_layout =
 924                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 925
 926            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
 927            // height. This is the size we will use to decide whether to render popovers above or below
 928            // the hovered line.
 929            let first_size = hover_popovers[0].size();
 930            let height_to_reserve = first_size.y()
 931                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
 932
 933            // Compute Hovered Point
 934            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
 935            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
 936            let hovered_point = content_origin + vec2f(x, y);
 937
 938            if hovered_point.y() - height_to_reserve > 0.0 {
 939                // There is enough space above. Render popovers above the hovered point
 940                let mut current_y = hovered_point.y();
 941                for hover_popover in hover_popovers {
 942                    let size = hover_popover.size();
 943                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
 944
 945                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 946                    if x_out_of_bounds < 0.0 {
 947                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 948                    }
 949
 950                    hover_popover.paint(
 951                        scene,
 952                        popover_origin,
 953                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 954                        editor,
 955                        cx,
 956                    );
 957
 958                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
 959                }
 960            } else {
 961                // There is not enough space above. Render popovers below the hovered point
 962                let mut current_y = hovered_point.y() + layout.position_map.line_height;
 963                for hover_popover in hover_popovers {
 964                    let size = hover_popover.size();
 965                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
 966
 967                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 968                    if x_out_of_bounds < 0.0 {
 969                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 970                    }
 971
 972                    hover_popover.paint(
 973                        scene,
 974                        popover_origin,
 975                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 976                        editor,
 977                        cx,
 978                    );
 979
 980                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
 981                }
 982            }
 983
 984            scene.pop_stacking_context();
 985        }
 986
 987        scene.pop_layer();
 988    }
 989
 990    fn paint_scrollbar(
 991        &mut self,
 992        scene: &mut SceneBuilder,
 993        bounds: RectF,
 994        layout: &mut LayoutState,
 995        cx: &mut ViewContext<Editor>,
 996    ) {
 997        enum ScrollbarMouseHandlers {}
 998        if layout.mode != EditorMode::Full {
 999            return;
1000        }
1001
1002        let style = &self.style.theme.scrollbar;
1003
1004        let top = bounds.min_y();
1005        let bottom = bounds.max_y();
1006        let right = bounds.max_x();
1007        let left = right - style.width;
1008        let row_range = &layout.scrollbar_row_range;
1009        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
1010
1011        let mut height = bounds.height();
1012        let mut first_row_y_offset = 0.0;
1013
1014        // Impose a minimum height on the scrollbar thumb
1015        let min_thumb_height =
1016            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
1017        let thumb_height = (row_range.end - row_range.start) * height / max_row;
1018        if thumb_height < min_thumb_height {
1019            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
1020            height -= min_thumb_height - thumb_height;
1021        }
1022
1023        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * height / max_row };
1024
1025        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
1026        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
1027        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
1028        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
1029
1030        if layout.show_scrollbars {
1031            scene.push_quad(Quad {
1032                bounds: track_bounds,
1033                border: style.track.border,
1034                background: style.track.background_color,
1035                ..Default::default()
1036            });
1037            scene.push_quad(Quad {
1038                bounds: thumb_bounds,
1039                border: style.thumb.border,
1040                background: style.thumb.background_color,
1041                corner_radius: style.thumb.corner_radius,
1042            });
1043        }
1044
1045        scene.push_cursor_region(CursorRegion {
1046            bounds: track_bounds,
1047            style: CursorStyle::Arrow,
1048        });
1049        scene.push_mouse_region(
1050            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1051                .on_move(move |_, editor: &mut Editor, cx| {
1052                    editor.scroll_manager.show_scrollbar(cx);
1053                })
1054                .on_down(MouseButton::Left, {
1055                    let row_range = row_range.clone();
1056                    move |event, editor: &mut Editor, cx| {
1057                        let y = event.position.y();
1058                        if y < thumb_top || thumb_bottom < y {
1059                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1060                            let top_row = center_row
1061                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1062                            let mut position = editor.scroll_position(cx);
1063                            position.set_y(top_row as f32);
1064                            editor.set_scroll_position(position, cx);
1065                        } else {
1066                            editor.scroll_manager.show_scrollbar(cx);
1067                        }
1068                    }
1069                })
1070                .on_drag(MouseButton::Left, {
1071                    move |event, editor: &mut Editor, cx| {
1072                        let y = event.prev_mouse_position.y();
1073                        let new_y = event.position.y();
1074                        if thumb_top < y && y < thumb_bottom {
1075                            let mut position = editor.scroll_position(cx);
1076                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1077                            if position.y() < 0.0 {
1078                                position.set_y(0.);
1079                            }
1080                            editor.set_scroll_position(position, cx);
1081                        }
1082                    }
1083                }),
1084        );
1085    }
1086
1087    #[allow(clippy::too_many_arguments)]
1088    fn paint_highlighted_range(
1089        &self,
1090        scene: &mut SceneBuilder,
1091        range: Range<DisplayPoint>,
1092        color: Color,
1093        corner_radius: f32,
1094        line_end_overshoot: f32,
1095        layout: &LayoutState,
1096        content_origin: Vector2F,
1097        scroll_top: f32,
1098        scroll_left: f32,
1099        bounds: RectF,
1100    ) {
1101        let start_row = layout.visible_display_row_range.start;
1102        let end_row = layout.visible_display_row_range.end;
1103        if range.start != range.end {
1104            let row_range = if range.end.column() == 0 {
1105                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1106            } else {
1107                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1108            };
1109
1110            let highlighted_range = HighlightedRange {
1111                color,
1112                line_height: layout.position_map.line_height,
1113                corner_radius,
1114                start_y: content_origin.y()
1115                    + row_range.start as f32 * layout.position_map.line_height
1116                    - scroll_top,
1117                lines: row_range
1118                    .into_iter()
1119                    .map(|row| {
1120                        let line_layout =
1121                            &layout.position_map.line_layouts[(row - start_row) as usize];
1122                        HighlightedRangeLine {
1123                            start_x: if row == range.start.row() {
1124                                content_origin.x()
1125                                    + line_layout.x_for_index(range.start.column() as usize)
1126                                    - scroll_left
1127                            } else {
1128                                content_origin.x() - scroll_left
1129                            },
1130                            end_x: if row == range.end.row() {
1131                                content_origin.x()
1132                                    + line_layout.x_for_index(range.end.column() as usize)
1133                                    - scroll_left
1134                            } else {
1135                                content_origin.x() + line_layout.width() + line_end_overshoot
1136                                    - scroll_left
1137                            },
1138                        }
1139                    })
1140                    .collect(),
1141            };
1142
1143            highlighted_range.paint(bounds, scene);
1144        }
1145    }
1146
1147    fn paint_blocks(
1148        &mut self,
1149        scene: &mut SceneBuilder,
1150        bounds: RectF,
1151        visible_bounds: RectF,
1152        layout: &mut LayoutState,
1153        editor: &mut Editor,
1154        cx: &mut ViewContext<Editor>,
1155    ) {
1156        let scroll_position = layout.position_map.snapshot.scroll_position();
1157        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1158        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1159
1160        for block in &mut layout.blocks {
1161            let mut origin = bounds.origin()
1162                + vec2f(
1163                    0.,
1164                    block.row as f32 * layout.position_map.line_height - scroll_top,
1165                );
1166            if !matches!(block.style, BlockStyle::Sticky) {
1167                origin += vec2f(-scroll_left, 0.);
1168            }
1169            block
1170                .element
1171                .paint(scene, origin, visible_bounds, editor, cx);
1172        }
1173    }
1174
1175    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1176        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1177        let style = &self.style;
1178
1179        cx.text_layout_cache()
1180            .layout_str(
1181                "1".repeat(digit_count).as_str(),
1182                style.text.font_size,
1183                &[(
1184                    digit_count,
1185                    RunStyle {
1186                        font_id: style.text.font_id,
1187                        color: Color::black(),
1188                        underline: Default::default(),
1189                    },
1190                )],
1191            )
1192            .width()
1193    }
1194
1195    //Folds contained in a hunk are ignored apart from shrinking visual size
1196    //If a fold contains any hunks then that fold line is marked as modified
1197    fn layout_git_gutters(
1198        &self,
1199        display_rows: Range<u32>,
1200        snapshot: &EditorSnapshot,
1201    ) -> Vec<DisplayDiffHunk> {
1202        let buffer_snapshot = &snapshot.buffer_snapshot;
1203
1204        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1205            .to_point(snapshot)
1206            .row;
1207        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1208            .to_point(snapshot)
1209            .row;
1210
1211        buffer_snapshot
1212            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row, false)
1213            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1214            .dedup()
1215            .collect()
1216    }
1217
1218    fn layout_line_numbers(
1219        &self,
1220        rows: Range<u32>,
1221        active_rows: &BTreeMap<u32, bool>,
1222        is_singleton: bool,
1223        snapshot: &EditorSnapshot,
1224        cx: &ViewContext<Editor>,
1225    ) -> (
1226        Vec<Option<text_layout::Line>>,
1227        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1228    ) {
1229        let style = &self.style;
1230        let include_line_numbers = snapshot.mode == EditorMode::Full;
1231        let mut line_number_layouts = Vec::with_capacity(rows.len());
1232        let mut fold_statuses = Vec::with_capacity(rows.len());
1233        let mut line_number = String::new();
1234        for (ix, row) in snapshot
1235            .buffer_rows(rows.start)
1236            .take((rows.end - rows.start) as usize)
1237            .enumerate()
1238        {
1239            let display_row = rows.start + ix as u32;
1240            let (active, color) = if active_rows.contains_key(&display_row) {
1241                (true, style.line_number_active)
1242            } else {
1243                (false, style.line_number)
1244            };
1245            if let Some(buffer_row) = row {
1246                if include_line_numbers {
1247                    line_number.clear();
1248                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1249                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1250                        &line_number,
1251                        style.text.font_size,
1252                        &[(
1253                            line_number.len(),
1254                            RunStyle {
1255                                font_id: style.text.font_id,
1256                                color,
1257                                underline: Default::default(),
1258                            },
1259                        )],
1260                    )));
1261                    fold_statuses.push(
1262                        is_singleton
1263                            .then(|| {
1264                                snapshot
1265                                    .fold_for_line(buffer_row)
1266                                    .map(|fold_status| (fold_status, buffer_row, active))
1267                            })
1268                            .flatten(),
1269                    )
1270                }
1271            } else {
1272                fold_statuses.push(None);
1273                line_number_layouts.push(None);
1274            }
1275        }
1276
1277        (line_number_layouts, fold_statuses)
1278    }
1279
1280    fn layout_lines(
1281        &mut self,
1282        rows: Range<u32>,
1283        snapshot: &EditorSnapshot,
1284        cx: &ViewContext<Editor>,
1285    ) -> Vec<text_layout::Line> {
1286        if rows.start >= rows.end {
1287            return Vec::new();
1288        }
1289
1290        // When the editor is empty and unfocused, then show the placeholder.
1291        if snapshot.is_empty() {
1292            let placeholder_style = self
1293                .style
1294                .placeholder_text
1295                .as_ref()
1296                .unwrap_or(&self.style.text);
1297            let placeholder_text = snapshot.placeholder_text();
1298            let placeholder_lines = placeholder_text
1299                .as_ref()
1300                .map_or("", AsRef::as_ref)
1301                .split('\n')
1302                .skip(rows.start as usize)
1303                .chain(iter::repeat(""))
1304                .take(rows.len());
1305            placeholder_lines
1306                .map(|line| {
1307                    cx.text_layout_cache().layout_str(
1308                        line,
1309                        placeholder_style.font_size,
1310                        &[(
1311                            line.len(),
1312                            RunStyle {
1313                                font_id: placeholder_style.font_id,
1314                                color: placeholder_style.color,
1315                                underline: Default::default(),
1316                            },
1317                        )],
1318                    )
1319                })
1320                .collect()
1321        } else {
1322            let style = &self.style;
1323            let chunks = snapshot
1324                .chunks(rows.clone(), true, Some(style.theme.suggestion))
1325                .map(|chunk| {
1326                    let mut highlight_style = chunk
1327                        .syntax_highlight_id
1328                        .and_then(|id| id.style(&style.syntax));
1329
1330                    if let Some(chunk_highlight) = chunk.highlight_style {
1331                        if let Some(highlight_style) = highlight_style.as_mut() {
1332                            highlight_style.highlight(chunk_highlight);
1333                        } else {
1334                            highlight_style = Some(chunk_highlight);
1335                        }
1336                    }
1337
1338                    let mut diagnostic_highlight = HighlightStyle::default();
1339
1340                    if chunk.is_unnecessary {
1341                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1342                    }
1343
1344                    if let Some(severity) = chunk.diagnostic_severity {
1345                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1346                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1347                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1348                            diagnostic_highlight.underline = Some(Underline {
1349                                color: Some(diagnostic_style.message.text.color),
1350                                thickness: 1.0.into(),
1351                                squiggly: true,
1352                            });
1353                        }
1354                    }
1355
1356                    if let Some(highlight_style) = highlight_style.as_mut() {
1357                        highlight_style.highlight(diagnostic_highlight);
1358                    } else {
1359                        highlight_style = Some(diagnostic_highlight);
1360                    }
1361
1362                    HighlightedChunk {
1363                        chunk: chunk.text,
1364                        style: highlight_style,
1365                        is_tab: chunk.is_tab,
1366                    }
1367                });
1368
1369            let settings = cx.global::<Settings>();
1370            let show_invisibles = settings
1371                .editor_overrides
1372                .show_invisibles
1373                .or(settings.editor_defaults.show_invisibles)
1374                .unwrap_or_default()
1375                == settings::ShowInvisibles::All;
1376            layout_highlighted_chunks(
1377                chunks,
1378                &style.text,
1379                cx.text_layout_cache(),
1380                cx.font_cache(),
1381                MAX_LINE_LEN,
1382                rows.len() as usize,
1383                show_invisibles,
1384            )
1385        }
1386    }
1387
1388    #[allow(clippy::too_many_arguments)]
1389    fn layout_blocks(
1390        &mut self,
1391        rows: Range<u32>,
1392        snapshot: &EditorSnapshot,
1393        editor_width: f32,
1394        scroll_width: f32,
1395        gutter_padding: f32,
1396        gutter_width: f32,
1397        em_width: f32,
1398        text_x: f32,
1399        line_height: f32,
1400        style: &EditorStyle,
1401        line_layouts: &[text_layout::Line],
1402        include_root: bool,
1403        editor: &mut Editor,
1404        cx: &mut LayoutContext<Editor>,
1405    ) -> (f32, Vec<BlockLayout>) {
1406        let tooltip_style = cx.global::<Settings>().theme.tooltip.clone();
1407        let scroll_x = snapshot.scroll_anchor.offset.x();
1408        let (fixed_blocks, non_fixed_blocks) = snapshot
1409            .blocks_in_range(rows.clone())
1410            .partition::<Vec<_>, _>(|(_, block)| match block {
1411                TransformBlock::ExcerptHeader { .. } => false,
1412                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1413            });
1414        let mut render_block = |block: &TransformBlock, width: f32| {
1415            let mut element = match block {
1416                TransformBlock::Custom(block) => {
1417                    let align_to = block
1418                        .position()
1419                        .to_point(&snapshot.buffer_snapshot)
1420                        .to_display_point(snapshot);
1421                    let anchor_x = text_x
1422                        + if rows.contains(&align_to.row()) {
1423                            line_layouts[(align_to.row() - rows.start) as usize]
1424                                .x_for_index(align_to.column() as usize)
1425                        } else {
1426                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1427                                .x_for_index(align_to.column() as usize)
1428                        };
1429
1430                    block.render(&mut BlockContext {
1431                        view_context: cx,
1432                        anchor_x,
1433                        gutter_padding,
1434                        line_height,
1435                        scroll_x,
1436                        gutter_width,
1437                        em_width,
1438                    })
1439                }
1440                TransformBlock::ExcerptHeader {
1441                    id,
1442                    buffer,
1443                    range,
1444                    starts_new_buffer,
1445                    ..
1446                } => {
1447                    let id = *id;
1448                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1449                        let jump_path = ProjectPath {
1450                            worktree_id: file.worktree_id(cx),
1451                            path: file.path.clone(),
1452                        };
1453                        let jump_anchor = range
1454                            .primary
1455                            .as_ref()
1456                            .map_or(range.context.start, |primary| primary.start);
1457                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1458
1459                        enum JumpIcon {}
1460                        MouseEventHandler::<JumpIcon, _>::new(id.into(), cx, |state, _| {
1461                            let style = style.jump_icon.style_for(state, false);
1462                            Svg::new("icons/arrow_up_right_8.svg")
1463                                .with_color(style.color)
1464                                .constrained()
1465                                .with_width(style.icon_width)
1466                                .aligned()
1467                                .contained()
1468                                .with_style(style.container)
1469                                .constrained()
1470                                .with_width(style.button_width)
1471                                .with_height(style.button_width)
1472                        })
1473                        .with_cursor_style(CursorStyle::PointingHand)
1474                        .on_click(MouseButton::Left, move |_, editor, cx| {
1475                            if let Some(workspace) = editor
1476                                .workspace
1477                                .as_ref()
1478                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1479                            {
1480                                workspace.update(cx, |workspace, cx| {
1481                                    Editor::jump(
1482                                        workspace,
1483                                        jump_path.clone(),
1484                                        jump_position,
1485                                        jump_anchor,
1486                                        cx,
1487                                    );
1488                                });
1489                            }
1490                        })
1491                        .with_tooltip::<JumpIcon>(
1492                            id.into(),
1493                            "Jump to Buffer".to_string(),
1494                            Some(Box::new(crate::OpenExcerpts)),
1495                            tooltip_style.clone(),
1496                            cx,
1497                        )
1498                        .aligned()
1499                        .flex_float()
1500                    });
1501
1502                    if *starts_new_buffer {
1503                        let style = &self.style.diagnostic_path_header;
1504                        let font_size =
1505                            (style.text_scale_factor * self.style.text.font_size).round();
1506
1507                        let path = buffer.resolve_file_path(cx, include_root);
1508                        let mut filename = None;
1509                        let mut parent_path = None;
1510                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1511                        if let Some(path) = path {
1512                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1513                            parent_path =
1514                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1515                        }
1516
1517                        Flex::row()
1518                            .with_child(
1519                                Label::new(
1520                                    filename.unwrap_or_else(|| "untitled".to_string()),
1521                                    style.filename.text.clone().with_font_size(font_size),
1522                                )
1523                                .contained()
1524                                .with_style(style.filename.container)
1525                                .aligned(),
1526                            )
1527                            .with_children(parent_path.map(|path| {
1528                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1529                                    .contained()
1530                                    .with_style(style.path.container)
1531                                    .aligned()
1532                            }))
1533                            .with_children(jump_icon)
1534                            .contained()
1535                            .with_style(style.container)
1536                            .with_padding_left(gutter_padding)
1537                            .with_padding_right(gutter_padding)
1538                            .expanded()
1539                            .into_any_named("path header block")
1540                    } else {
1541                        let text_style = self.style.text.clone();
1542                        Flex::row()
1543                            .with_child(Label::new("", text_style))
1544                            .with_children(jump_icon)
1545                            .contained()
1546                            .with_padding_left(gutter_padding)
1547                            .with_padding_right(gutter_padding)
1548                            .expanded()
1549                            .into_any_named("collapsed context")
1550                    }
1551                }
1552            };
1553
1554            element.layout(
1555                SizeConstraint {
1556                    min: Vector2F::zero(),
1557                    max: vec2f(width, block.height() as f32 * line_height),
1558                },
1559                editor,
1560                cx,
1561            );
1562            element
1563        };
1564
1565        let mut fixed_block_max_width = 0f32;
1566        let mut blocks = Vec::new();
1567        for (row, block) in fixed_blocks {
1568            let element = render_block(block, f32::INFINITY);
1569            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1570            blocks.push(BlockLayout {
1571                row,
1572                element,
1573                style: BlockStyle::Fixed,
1574            });
1575        }
1576        for (row, block) in non_fixed_blocks {
1577            let style = match block {
1578                TransformBlock::Custom(block) => block.style(),
1579                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1580            };
1581            let width = match style {
1582                BlockStyle::Sticky => editor_width,
1583                BlockStyle::Flex => editor_width
1584                    .max(fixed_block_max_width)
1585                    .max(gutter_width + scroll_width),
1586                BlockStyle::Fixed => unreachable!(),
1587            };
1588            let element = render_block(block, width);
1589            blocks.push(BlockLayout {
1590                row,
1591                element,
1592                style,
1593            });
1594        }
1595        (
1596            scroll_width.max(fixed_block_max_width - gutter_width),
1597            blocks,
1598        )
1599    }
1600}
1601
1602impl Element<Editor> for EditorElement {
1603    type LayoutState = LayoutState;
1604    type PaintState = ();
1605
1606    fn layout(
1607        &mut self,
1608        constraint: SizeConstraint,
1609        editor: &mut Editor,
1610        cx: &mut LayoutContext<Editor>,
1611    ) -> (Vector2F, Self::LayoutState) {
1612        let mut size = constraint.max;
1613        if size.x().is_infinite() {
1614            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1615        }
1616
1617        let snapshot = editor.snapshot(cx);
1618        let style = self.style.clone();
1619        let line_height = style.text.line_height(cx.font_cache());
1620
1621        let gutter_padding;
1622        let gutter_width;
1623        let gutter_margin;
1624        if snapshot.mode == EditorMode::Full {
1625            let em_width = style.text.em_width(cx.font_cache());
1626            gutter_padding = (em_width * style.gutter_padding_factor).round();
1627            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1628            gutter_margin = -style.text.descent(cx.font_cache());
1629        } else {
1630            gutter_padding = 0.0;
1631            gutter_width = 0.0;
1632            gutter_margin = 0.0;
1633        };
1634
1635        let text_width = size.x() - gutter_width;
1636        let em_width = style.text.em_width(cx.font_cache());
1637        let em_advance = style.text.em_advance(cx.font_cache());
1638        let overscroll = vec2f(em_width, 0.);
1639        let snapshot = {
1640            editor.set_visible_line_count(size.y() / line_height);
1641
1642            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
1643            let wrap_width = match editor.soft_wrap_mode(cx) {
1644                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
1645                SoftWrap::EditorWidth => editor_width,
1646                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
1647            };
1648
1649            if editor.set_wrap_width(Some(wrap_width), cx) {
1650                editor.snapshot(cx)
1651            } else {
1652                snapshot
1653            }
1654        };
1655
1656        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1657        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1658            size.set_y(
1659                scroll_height
1660                    .min(constraint.max_along(Axis::Vertical))
1661                    .max(constraint.min_along(Axis::Vertical))
1662                    .min(line_height * max_lines as f32),
1663            )
1664        } else if let EditorMode::SingleLine = snapshot.mode {
1665            size.set_y(
1666                line_height
1667                    .min(constraint.max_along(Axis::Vertical))
1668                    .max(constraint.min_along(Axis::Vertical)),
1669            )
1670        } else if size.y().is_infinite() {
1671            size.set_y(scroll_height);
1672        }
1673        let gutter_size = vec2f(gutter_width, size.y());
1674        let text_size = vec2f(text_width, size.y());
1675
1676        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
1677        let mut snapshot = editor.snapshot(cx);
1678
1679        let scroll_position = snapshot.scroll_position();
1680        // The scroll position is a fractional point, the whole number of which represents
1681        // the top of the window in terms of display rows.
1682        let start_row = scroll_position.y() as u32;
1683        let height_in_lines = size.y() / line_height;
1684        let max_row = snapshot.max_point().row();
1685
1686        // Add 1 to ensure selections bleed off screen
1687        let end_row = 1 + cmp::min(
1688            (scroll_position.y() + height_in_lines).ceil() as u32,
1689            max_row,
1690        );
1691
1692        let start_anchor = if start_row == 0 {
1693            Anchor::min()
1694        } else {
1695            snapshot
1696                .buffer_snapshot
1697                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
1698        };
1699        let end_anchor = if end_row > max_row {
1700            Anchor::max()
1701        } else {
1702            snapshot
1703                .buffer_snapshot
1704                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
1705        };
1706
1707        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
1708        let mut active_rows = BTreeMap::new();
1709        let mut fold_ranges = Vec::new();
1710        let is_singleton = editor.is_singleton(cx);
1711
1712        let highlighted_rows = editor.highlighted_rows();
1713        let theme = cx.global::<Settings>().theme.as_ref();
1714        let highlighted_ranges = editor.background_highlights_in_range(
1715            start_anchor..end_anchor,
1716            &snapshot.display_snapshot,
1717            theme,
1718        );
1719
1720        fold_ranges.extend(
1721            snapshot
1722                .folds_in_range(start_anchor..end_anchor)
1723                .map(|anchor| {
1724                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
1725                    (
1726                        start.row,
1727                        start.to_display_point(&snapshot.display_snapshot)
1728                            ..anchor.end.to_display_point(&snapshot),
1729                    )
1730                }),
1731        );
1732
1733        let mut remote_selections = HashMap::default();
1734        for (replica_id, line_mode, cursor_shape, selection) in snapshot
1735            .buffer_snapshot
1736            .remote_selections_in_range(&(start_anchor..end_anchor))
1737        {
1738            // The local selections match the leader's selections.
1739            if Some(replica_id) == editor.leader_replica_id {
1740                continue;
1741            }
1742            remote_selections
1743                .entry(replica_id)
1744                .or_insert(Vec::new())
1745                .push(SelectionLayout::new(
1746                    selection,
1747                    line_mode,
1748                    cursor_shape,
1749                    &snapshot.display_snapshot,
1750                ));
1751        }
1752        selections.extend(remote_selections);
1753
1754        if editor.show_local_selections {
1755            let mut local_selections = editor
1756                .selections
1757                .disjoint_in_range(start_anchor..end_anchor, cx);
1758            local_selections.extend(editor.selections.pending(cx));
1759            for selection in &local_selections {
1760                let is_empty = selection.start == selection.end;
1761                let selection_start = snapshot.prev_line_boundary(selection.start).1;
1762                let selection_end = snapshot.next_line_boundary(selection.end).1;
1763                for row in cmp::max(selection_start.row(), start_row)
1764                    ..=cmp::min(selection_end.row(), end_row)
1765                {
1766                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
1767                    *contains_non_empty_selection |= !is_empty;
1768                }
1769            }
1770
1771            // Render the local selections in the leader's color when following.
1772            let local_replica_id = editor
1773                .leader_replica_id
1774                .unwrap_or_else(|| editor.replica_id(cx));
1775
1776            selections.push((
1777                local_replica_id,
1778                local_selections
1779                    .into_iter()
1780                    .map(|selection| {
1781                        SelectionLayout::new(
1782                            selection,
1783                            editor.selections.line_mode,
1784                            editor.cursor_shape,
1785                            &snapshot.display_snapshot,
1786                        )
1787                    })
1788                    .collect(),
1789            ));
1790        }
1791
1792        let show_scrollbars = editor.scroll_manager.scrollbars_visible();
1793        let include_root = editor
1794            .project
1795            .as_ref()
1796            .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1797            .unwrap_or_default();
1798
1799        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
1800            .into_iter()
1801            .map(|(id, fold)| {
1802                let color = self
1803                    .style
1804                    .folds
1805                    .ellipses
1806                    .background
1807                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize), false)
1808                    .color;
1809
1810                (id, fold, color)
1811            })
1812            .collect();
1813
1814        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
1815            start_row..end_row,
1816            &active_rows,
1817            is_singleton,
1818            &snapshot,
1819            cx,
1820        );
1821
1822        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
1823
1824        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
1825
1826        let mut max_visible_line_width = 0.0;
1827        let line_layouts = self.layout_lines(start_row..end_row, &snapshot, cx);
1828        for line in &line_layouts {
1829            if line.width() > max_visible_line_width {
1830                max_visible_line_width = line.width();
1831            }
1832        }
1833
1834        let style = self.style.clone();
1835        let longest_line_width = layout_line(
1836            snapshot.longest_row(),
1837            &snapshot,
1838            &style,
1839            cx.text_layout_cache(),
1840        )
1841        .width();
1842        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
1843        let em_width = style.text.em_width(cx.font_cache());
1844        let (scroll_width, blocks) = self.layout_blocks(
1845            start_row..end_row,
1846            &snapshot,
1847            size.x(),
1848            scroll_width,
1849            gutter_padding,
1850            gutter_width,
1851            em_width,
1852            gutter_width + gutter_margin,
1853            line_height,
1854            &style,
1855            &line_layouts,
1856            include_root,
1857            editor,
1858            cx,
1859        );
1860
1861        let scroll_max = vec2f(
1862            ((scroll_width - text_size.x()) / em_width).max(0.0),
1863            max_row as f32,
1864        );
1865
1866        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
1867
1868        let autoscrolled = if autoscroll_horizontally {
1869            editor.autoscroll_horizontally(
1870                start_row,
1871                text_size.x(),
1872                scroll_width,
1873                em_width,
1874                &line_layouts,
1875                cx,
1876            )
1877        } else {
1878            false
1879        };
1880
1881        if clamped || autoscrolled {
1882            snapshot = editor.snapshot(cx);
1883        }
1884
1885        let newest_selection_head = editor
1886            .selections
1887            .newest::<usize>(cx)
1888            .head()
1889            .to_display_point(&snapshot);
1890        let style = editor.style(cx);
1891
1892        let mut context_menu = None;
1893        let mut code_actions_indicator = None;
1894        if (start_row..end_row).contains(&newest_selection_head.row()) {
1895            if editor.context_menu_visible() {
1896                context_menu = editor.render_context_menu(newest_selection_head, style.clone(), cx);
1897            }
1898
1899            let active = matches!(
1900                editor.context_menu,
1901                Some(crate::ContextMenu::CodeActions(_))
1902            );
1903
1904            code_actions_indicator = editor
1905                .render_code_actions_indicator(&style, active, cx)
1906                .map(|indicator| (newest_selection_head.row(), indicator));
1907        }
1908
1909        let visible_rows = start_row..start_row + line_layouts.len() as u32;
1910        let mut hover = editor
1911            .hover_state
1912            .render(&snapshot, &style, visible_rows, cx);
1913        let mode = editor.mode;
1914
1915        let mut fold_indicators = editor.render_fold_indicators(
1916            fold_statuses,
1917            &style,
1918            editor.gutter_hovered,
1919            line_height,
1920            gutter_margin,
1921            cx,
1922        );
1923
1924        if let Some((_, context_menu)) = context_menu.as_mut() {
1925            context_menu.layout(
1926                SizeConstraint {
1927                    min: Vector2F::zero(),
1928                    max: vec2f(
1929                        cx.window_size().x() * 0.7,
1930                        (12. * line_height).min((size.y() - line_height) / 2.),
1931                    ),
1932                },
1933                editor,
1934                cx,
1935            );
1936        }
1937
1938        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
1939            indicator.layout(
1940                SizeConstraint::strict_along(
1941                    Axis::Vertical,
1942                    line_height * style.code_actions.vertical_scale,
1943                ),
1944                editor,
1945                cx,
1946            );
1947        }
1948
1949        for fold_indicator in fold_indicators.iter_mut() {
1950            if let Some(indicator) = fold_indicator.as_mut() {
1951                indicator.layout(
1952                    SizeConstraint::strict_along(
1953                        Axis::Vertical,
1954                        line_height * style.code_actions.vertical_scale,
1955                    ),
1956                    editor,
1957                    cx,
1958                );
1959            }
1960        }
1961
1962        if let Some((_, hover_popovers)) = hover.as_mut() {
1963            for hover_popover in hover_popovers.iter_mut() {
1964                hover_popover.layout(
1965                    SizeConstraint {
1966                        min: Vector2F::zero(),
1967                        max: vec2f(
1968                            (120. * em_width) // Default size
1969                                .min(size.x() / 2.) // Shrink to half of the editor width
1970                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
1971                            (16. * line_height) // Default size
1972                                .min(size.y() / 2.) // Shrink to half of the editor height
1973                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
1974                        ),
1975                    },
1976                    editor,
1977                    cx,
1978                );
1979            }
1980        }
1981
1982        (
1983            size,
1984            LayoutState {
1985                mode,
1986                position_map: Arc::new(PositionMap {
1987                    size,
1988                    scroll_max,
1989                    line_layouts,
1990                    line_height,
1991                    em_width,
1992                    em_advance,
1993                    snapshot,
1994                }),
1995                visible_display_row_range: start_row..end_row,
1996                gutter_size,
1997                gutter_padding,
1998                text_size,
1999                scrollbar_row_range,
2000                show_scrollbars,
2001                max_row,
2002                gutter_margin,
2003                active_rows,
2004                highlighted_rows,
2005                highlighted_ranges,
2006                fold_ranges,
2007                line_number_layouts,
2008                display_hunks,
2009                blocks,
2010                selections,
2011                context_menu,
2012                code_actions_indicator,
2013                fold_indicators,
2014                hover_popovers: hover,
2015            },
2016        )
2017    }
2018
2019    fn paint(
2020        &mut self,
2021        scene: &mut SceneBuilder,
2022        bounds: RectF,
2023        visible_bounds: RectF,
2024        layout: &mut Self::LayoutState,
2025        editor: &mut Editor,
2026        cx: &mut ViewContext<Editor>,
2027    ) -> Self::PaintState {
2028        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2029        scene.push_layer(Some(visible_bounds));
2030
2031        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2032        let text_bounds = RectF::new(
2033            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2034            layout.text_size,
2035        );
2036
2037        Self::attach_mouse_handlers(
2038            scene,
2039            &layout.position_map,
2040            layout.hover_popovers.is_some(),
2041            visible_bounds,
2042            text_bounds,
2043            gutter_bounds,
2044            bounds,
2045            cx,
2046        );
2047
2048        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2049        if layout.gutter_size.x() > 0. {
2050            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2051        }
2052        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2053
2054        scene.push_layer(Some(bounds));
2055        if !layout.blocks.is_empty() {
2056            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2057        }
2058        self.paint_scrollbar(scene, bounds, layout, cx);
2059        scene.pop_layer();
2060
2061        scene.pop_layer();
2062    }
2063
2064    fn rect_for_text_range(
2065        &self,
2066        range_utf16: Range<usize>,
2067        bounds: RectF,
2068        _: RectF,
2069        layout: &Self::LayoutState,
2070        _: &Self::PaintState,
2071        _: &Editor,
2072        _: &ViewContext<Editor>,
2073    ) -> Option<RectF> {
2074        let text_bounds = RectF::new(
2075            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2076            layout.text_size,
2077        );
2078        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2079        let scroll_position = layout.position_map.snapshot.scroll_position();
2080        let start_row = scroll_position.y() as u32;
2081        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2082        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2083
2084        let range_start = OffsetUtf16(range_utf16.start)
2085            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2086        if range_start.row() < start_row {
2087            return None;
2088        }
2089
2090        let line = layout
2091            .position_map
2092            .line_layouts
2093            .get((range_start.row() - start_row) as usize)?;
2094        let range_start_x = line.x_for_index(range_start.column() as usize);
2095        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2096        Some(RectF::new(
2097            content_origin
2098                + vec2f(
2099                    range_start_x,
2100                    range_start_y + layout.position_map.line_height,
2101                )
2102                - vec2f(scroll_left, scroll_top),
2103            vec2f(
2104                layout.position_map.em_width,
2105                layout.position_map.line_height,
2106            ),
2107        ))
2108    }
2109
2110    fn debug(
2111        &self,
2112        bounds: RectF,
2113        _: &Self::LayoutState,
2114        _: &Self::PaintState,
2115        _: &Editor,
2116        _: &ViewContext<Editor>,
2117    ) -> json::Value {
2118        json!({
2119            "type": "BufferElement",
2120            "bounds": bounds.to_json()
2121        })
2122    }
2123}
2124
2125type BufferRow = u32;
2126
2127pub struct LayoutState {
2128    position_map: Arc<PositionMap>,
2129    gutter_size: Vector2F,
2130    gutter_padding: f32,
2131    gutter_margin: f32,
2132    text_size: Vector2F,
2133    mode: EditorMode,
2134    visible_display_row_range: Range<u32>,
2135    active_rows: BTreeMap<u32, bool>,
2136    highlighted_rows: Option<Range<u32>>,
2137    line_number_layouts: Vec<Option<text_layout::Line>>,
2138    display_hunks: Vec<DisplayDiffHunk>,
2139    blocks: Vec<BlockLayout>,
2140    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2141    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2142    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2143    scrollbar_row_range: Range<f32>,
2144    show_scrollbars: bool,
2145    max_row: u32,
2146    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2147    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2148    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2149    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2150}
2151
2152pub struct PositionMap {
2153    size: Vector2F,
2154    line_height: f32,
2155    scroll_max: Vector2F,
2156    em_width: f32,
2157    em_advance: f32,
2158    line_layouts: Vec<text_layout::Line>,
2159    snapshot: EditorSnapshot,
2160}
2161
2162impl PositionMap {
2163    /// Returns two display points:
2164    /// 1. The nearest *valid* position in the editor
2165    /// 2. An unclipped, potentially *invalid* position that maps directly to
2166    ///    the given pixel position.
2167    fn point_for_position(
2168        &self,
2169        text_bounds: RectF,
2170        position: Vector2F,
2171    ) -> (DisplayPoint, DisplayPoint) {
2172        let scroll_position = self.snapshot.scroll_position();
2173        let position = position - text_bounds.origin();
2174        let y = position.y().max(0.0).min(self.size.y());
2175        let x = position.x() + (scroll_position.x() * self.em_width);
2176        let row = (y / self.line_height + scroll_position.y()) as u32;
2177        let (column, x_overshoot) = if let Some(line) = self
2178            .line_layouts
2179            .get(row as usize - scroll_position.y() as usize)
2180        {
2181            if let Some(ix) = line.index_for_x(x) {
2182                (ix as u32, 0.0)
2183            } else {
2184                (line.len() as u32, 0f32.max(x - line.width()))
2185            }
2186        } else {
2187            (0, x)
2188        };
2189
2190        let mut target_point = DisplayPoint::new(row, column);
2191        let point = self.snapshot.clip_point(target_point, Bias::Left);
2192        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2193
2194        (point, target_point)
2195    }
2196}
2197
2198struct BlockLayout {
2199    row: u32,
2200    element: AnyElement<Editor>,
2201    style: BlockStyle,
2202}
2203
2204fn layout_line(
2205    row: u32,
2206    snapshot: &EditorSnapshot,
2207    style: &EditorStyle,
2208    layout_cache: &TextLayoutCache,
2209) -> text_layout::Line {
2210    let mut line = snapshot.line(row);
2211
2212    if line.len() > MAX_LINE_LEN {
2213        let mut len = MAX_LINE_LEN;
2214        while !line.is_char_boundary(len) {
2215            len -= 1;
2216        }
2217
2218        line.truncate(len);
2219    }
2220
2221    layout_cache.layout_str(
2222        &line,
2223        style.text.font_size,
2224        &[(
2225            snapshot.line_len(row) as usize,
2226            RunStyle {
2227                font_id: style.text.font_id,
2228                color: Color::black(),
2229                underline: Default::default(),
2230            },
2231        )],
2232    )
2233}
2234
2235#[derive(Debug)]
2236pub struct Cursor {
2237    origin: Vector2F,
2238    block_width: f32,
2239    line_height: f32,
2240    color: Color,
2241    shape: CursorShape,
2242    block_text: Option<Line>,
2243}
2244
2245impl Cursor {
2246    pub fn new(
2247        origin: Vector2F,
2248        block_width: f32,
2249        line_height: f32,
2250        color: Color,
2251        shape: CursorShape,
2252        block_text: Option<Line>,
2253    ) -> Cursor {
2254        Cursor {
2255            origin,
2256            block_width,
2257            line_height,
2258            color,
2259            shape,
2260            block_text,
2261        }
2262    }
2263
2264    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2265        RectF::new(
2266            self.origin + origin,
2267            vec2f(self.block_width, self.line_height),
2268        )
2269    }
2270
2271    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2272        let bounds = match self.shape {
2273            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2274            CursorShape::Block | CursorShape::Hollow => RectF::new(
2275                self.origin + origin,
2276                vec2f(self.block_width, self.line_height),
2277            ),
2278            CursorShape::Underscore => RectF::new(
2279                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2280                vec2f(self.block_width, 2.0),
2281            ),
2282        };
2283
2284        //Draw background or border quad
2285        if matches!(self.shape, CursorShape::Hollow) {
2286            scene.push_quad(Quad {
2287                bounds,
2288                background: None,
2289                border: Border::all(1., self.color),
2290                corner_radius: 0.,
2291            });
2292        } else {
2293            scene.push_quad(Quad {
2294                bounds,
2295                background: Some(self.color),
2296                border: Default::default(),
2297                corner_radius: 0.,
2298            });
2299        }
2300
2301        if let Some(block_text) = &self.block_text {
2302            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2303        }
2304    }
2305
2306    pub fn shape(&self) -> CursorShape {
2307        self.shape
2308    }
2309}
2310
2311#[derive(Debug)]
2312pub struct HighlightedRange {
2313    pub start_y: f32,
2314    pub line_height: f32,
2315    pub lines: Vec<HighlightedRangeLine>,
2316    pub color: Color,
2317    pub corner_radius: f32,
2318}
2319
2320#[derive(Debug)]
2321pub struct HighlightedRangeLine {
2322    pub start_x: f32,
2323    pub end_x: f32,
2324}
2325
2326impl HighlightedRange {
2327    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2328        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2329            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2330            self.paint_lines(
2331                self.start_y + self.line_height,
2332                &self.lines[1..],
2333                bounds,
2334                scene,
2335            );
2336        } else {
2337            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2338        }
2339    }
2340
2341    fn paint_lines(
2342        &self,
2343        start_y: f32,
2344        lines: &[HighlightedRangeLine],
2345        bounds: RectF,
2346        scene: &mut SceneBuilder,
2347    ) {
2348        if lines.is_empty() {
2349            return;
2350        }
2351
2352        let mut path = PathBuilder::new();
2353        let first_line = lines.first().unwrap();
2354        let last_line = lines.last().unwrap();
2355
2356        let first_top_left = vec2f(first_line.start_x, start_y);
2357        let first_top_right = vec2f(first_line.end_x, start_y);
2358
2359        let curve_height = vec2f(0., self.corner_radius);
2360        let curve_width = |start_x: f32, end_x: f32| {
2361            let max = (end_x - start_x) / 2.;
2362            let width = if max < self.corner_radius {
2363                max
2364            } else {
2365                self.corner_radius
2366            };
2367
2368            vec2f(width, 0.)
2369        };
2370
2371        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2372        path.reset(first_top_right - top_curve_width);
2373        path.curve_to(first_top_right + curve_height, first_top_right);
2374
2375        let mut iter = lines.iter().enumerate().peekable();
2376        while let Some((ix, line)) = iter.next() {
2377            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2378
2379            if let Some((_, next_line)) = iter.peek() {
2380                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2381
2382                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2383                    Ordering::Equal => {
2384                        path.line_to(bottom_right);
2385                    }
2386                    Ordering::Less => {
2387                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2388                        path.line_to(bottom_right - curve_height);
2389                        if self.corner_radius > 0. {
2390                            path.curve_to(bottom_right - curve_width, bottom_right);
2391                        }
2392                        path.line_to(next_top_right + curve_width);
2393                        if self.corner_radius > 0. {
2394                            path.curve_to(next_top_right + curve_height, next_top_right);
2395                        }
2396                    }
2397                    Ordering::Greater => {
2398                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2399                        path.line_to(bottom_right - curve_height);
2400                        if self.corner_radius > 0. {
2401                            path.curve_to(bottom_right + curve_width, bottom_right);
2402                        }
2403                        path.line_to(next_top_right - curve_width);
2404                        if self.corner_radius > 0. {
2405                            path.curve_to(next_top_right + curve_height, next_top_right);
2406                        }
2407                    }
2408                }
2409            } else {
2410                let curve_width = curve_width(line.start_x, line.end_x);
2411                path.line_to(bottom_right - curve_height);
2412                if self.corner_radius > 0. {
2413                    path.curve_to(bottom_right - curve_width, bottom_right);
2414                }
2415
2416                let bottom_left = vec2f(line.start_x, bottom_right.y());
2417                path.line_to(bottom_left + curve_width);
2418                if self.corner_radius > 0. {
2419                    path.curve_to(bottom_left - curve_height, bottom_left);
2420                }
2421            }
2422        }
2423
2424        if first_line.start_x > last_line.start_x {
2425            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2426            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2427            path.line_to(second_top_left + curve_height);
2428            if self.corner_radius > 0. {
2429                path.curve_to(second_top_left + curve_width, second_top_left);
2430            }
2431            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2432            path.line_to(first_bottom_left - curve_width);
2433            if self.corner_radius > 0. {
2434                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2435            }
2436        }
2437
2438        path.line_to(first_top_left + curve_height);
2439        if self.corner_radius > 0. {
2440            path.curve_to(first_top_left + top_curve_width, first_top_left);
2441        }
2442        path.line_to(first_top_right - top_curve_width);
2443
2444        scene.push_path(path.build(self.color, Some(bounds)));
2445    }
2446}
2447
2448pub fn position_to_display_point(
2449    position: Vector2F,
2450    text_bounds: RectF,
2451    position_map: &PositionMap,
2452) -> Option<DisplayPoint> {
2453    if text_bounds.contains_point(position) {
2454        let (point, target_point) = position_map.point_for_position(text_bounds, position);
2455        if point == target_point {
2456            Some(point)
2457        } else {
2458            None
2459        }
2460    } else {
2461        None
2462    }
2463}
2464
2465pub fn range_to_bounds(
2466    range: &Range<DisplayPoint>,
2467    content_origin: Vector2F,
2468    scroll_left: f32,
2469    scroll_top: f32,
2470    visible_row_range: &Range<u32>,
2471    line_end_overshoot: f32,
2472    position_map: &PositionMap,
2473) -> impl Iterator<Item = RectF> {
2474    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2475
2476    if range.start == range.end {
2477        return bounds.into_iter();
2478    }
2479
2480    let start_row = visible_row_range.start;
2481    let end_row = visible_row_range.end;
2482
2483    let row_range = if range.end.column() == 0 {
2484        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2485    } else {
2486        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2487    };
2488
2489    let first_y =
2490        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
2491
2492    for (idx, row) in row_range.enumerate() {
2493        let line_layout = &position_map.line_layouts[(row - start_row) as usize];
2494
2495        let start_x = if row == range.start.row() {
2496            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
2497                - scroll_left
2498        } else {
2499            content_origin.x() - scroll_left
2500        };
2501
2502        let end_x = if row == range.end.row() {
2503            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
2504        } else {
2505            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
2506        };
2507
2508        bounds.push(RectF::from_points(
2509            vec2f(start_x, first_y + position_map.line_height * idx as f32),
2510            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
2511        ))
2512    }
2513
2514    bounds.into_iter()
2515}
2516
2517pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2518    delta.powf(1.5) / 100.0
2519}
2520
2521fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2522    delta.powf(1.2) / 300.0
2523}
2524
2525#[cfg(test)]
2526mod tests {
2527    use super::*;
2528    use crate::{
2529        display_map::{BlockDisposition, BlockProperties},
2530        Editor, MultiBuffer,
2531    };
2532    use gpui::TestAppContext;
2533    use settings::Settings;
2534    use std::sync::Arc;
2535    use util::test::sample_text;
2536
2537    #[gpui::test]
2538    fn test_layout_line_numbers(cx: &mut TestAppContext) {
2539        cx.update(|cx| cx.set_global(Settings::test(cx)));
2540        let (_, editor) = cx.add_window(|cx| {
2541            let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2542            Editor::new(EditorMode::Full, buffer, None, None, cx)
2543        });
2544        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2545
2546        let layouts = editor.update(cx, |editor, cx| {
2547            let snapshot = editor.snapshot(cx);
2548            element
2549                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
2550                .0
2551        });
2552        assert_eq!(layouts.len(), 6);
2553    }
2554
2555    #[gpui::test]
2556    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
2557        cx.update(|cx| cx.set_global(Settings::test(cx)));
2558        let (_, editor) = cx.add_window(|cx| {
2559            let buffer = MultiBuffer::build_simple("", cx);
2560            Editor::new(EditorMode::Full, buffer, None, None, cx)
2561        });
2562
2563        editor.update(cx, |editor, cx| {
2564            editor.set_placeholder_text("hello", cx);
2565            editor.insert_blocks(
2566                [BlockProperties {
2567                    style: BlockStyle::Fixed,
2568                    disposition: BlockDisposition::Above,
2569                    height: 3,
2570                    position: Anchor::min(),
2571                    render: Arc::new(|_| Empty::new().into_any()),
2572                }],
2573                cx,
2574            );
2575
2576            // Blur the editor so that it displays placeholder text.
2577            cx.blur();
2578        });
2579
2580        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
2581        let (size, mut state) = editor.update(cx, |editor, cx| {
2582            let mut new_parents = Default::default();
2583            let mut notify_views_if_parents_change = Default::default();
2584            let mut layout_cx = LayoutContext::new(
2585                cx,
2586                &mut new_parents,
2587                &mut notify_views_if_parents_change,
2588                false,
2589            );
2590            element.layout(
2591                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2592                editor,
2593                &mut layout_cx,
2594            )
2595        });
2596
2597        assert_eq!(state.position_map.line_layouts.len(), 4);
2598        assert_eq!(
2599            state
2600                .line_number_layouts
2601                .iter()
2602                .map(Option::is_some)
2603                .collect::<Vec<_>>(),
2604            &[false, false, false, true]
2605        );
2606
2607        // Don't panic.
2608        let mut scene = SceneBuilder::new(1.0);
2609        let bounds = RectF::new(Default::default(), size);
2610        editor.update(cx, |editor, cx| {
2611            element.paint(&mut scene, bounds, bounds, &mut state, editor, cx);
2612        });
2613    }
2614}